Kyushu University Academic Staff Educational and Research Activities Database
List of Papers
CHANGHONG HU Last modified date:2020.07.02

Professor / Division of Renewable Energy Dynamics / Research Institute for Applied Mechanics


Papers
1. Changhong Hu, Mohamed M. Kamra, An unstructured mesh method for numerical simulation of violent sloshing flows, Journal of Hydrodynamics, 10.1007/s42241-020-0019-z, 32, 2, 259-266, 2020.04, An unstructured mesh Reynolds-averaged Navier-Stokes (RANS) solver has been developed for numerical simulation of violent sloshing flows inside a tank with complicated inner structures. The numerical solver employs the unstructured multi-dimensional tangent hyperbolic interface capturing method (UMTHINC) for free-surface capturing combined with various turbulence models. The sloshing motion is numerically modeled using the body-force method which introduces a source term into the momentum equation corresponding to the tank motion profile. Numerical simulations of the tank sloshing problems are performed for different test cases with various oscillation frequencies. The performance of the interface capturing method has been discussed and the effect of turbulence model choice on loading predictions is highlighted by studying several RANS models and analyzing its effect on fluid motion and impact pressure. Numerical simulations of the sloshing inside the tank with a vertical baffle has also been conducted and a discussion is provided on different numerical treatment of the baffle..
2. Jabir Al Salami, Changhong Hu, Kazuaki Hanada, A study on smoothed particle hydrodynamics for liquid metal flow simulation, Evergreen, 6, 3, 190-199, 2019.09, In order to address the problem of heat and particle removal in tokamak-type, magnetic confinement nuclear fusion reactors, a divertor that utilizes liquid metal is suggested to replace solid tungsten divertors due to concerns regarding their structural integrity at high energy fluxes. The operation of such a device gives rise to phenomena spanning multiple disciplines of physics such as fluid dynamics, electromagnetics, thermodynamics and plasma physics. Smoothed Particle Hydrodynamics (SPH) is a Lagrangian, mesh-free numerical method that has been proven effective in a variety of disciplines. In this work, the hydrodynamic aspect of the liquid metal divertor is simulated using SPH, paving the way to implement additional physics in future work..
3. Hongzhong Zhu, Changhong Hu, Makoto Sueyoshi, Shigeo Yoshida, Integration of a semisubmersible floating wind turbine and wave energy converters
an experimental study on motion reduction, Journal of Marine Science and Technology (Japan), 10.1007/s00773-019-00671-y, 2019.08, The integration of wave energy converters and a floating wind turbine has the potential to reduce the cost of energy, since they can share the mooring system and the infrastructure of the power grid. In this study, oscillating-water-column-type wave energy converters mounted on a semisubmersible-type floating wind turbine are presented. Water tank tests are carried out to illustrate that the wave energy converters can not only capture the wave energy but also help in reducing the motion of the floating platform when active control is applied. This study provides a new perspective on hybrid renewable energy application to widen renewable energy penetration by enhancing system reliability..
4. Cheng Liu, Changhong Hu, An actuator line - immersed boundary method for simulation of multiple tidal turbines, Renewable Energy, 10.1016/j.renene.2019.01.019, 136, 473-490, 2019.06, This work proposes an efficient actuator line – immersed boundary (AL-IB) method to predict the wake of multiple horizontal-axis tidal turbines (HATTs). A sharp IB method with a simple adaptive mesh refinement strategy is used to improve the computational efficiency. The velocity and other scalar fields adjacent to the solid surface are reconstructed by a moving least square (MLS) interpolation. A computationally efficient AL model is applied to represent the rotors by adding source term to the governing equation rather than resolving the fully geometry of the blade. To predict the turbulent wake, the AL-IB method is implemented with an unsteady Reynolds-averaged Navier–Stokes (URANS) solver. Performance of three types of turbulence models, k−ω−SST model, standard and corrected k−ω model are evaluated. An efficient wall function model is proposed for the MLS-IB approach. The accuracy of the present AL-IB method is validated by numerical tests of a single rotor and multiple tandem arranged IFREMER rotors [1,2]. Wake interference of Manchester rotors [3] with side by side arrangement is also investigated numerically. The predicted wake velocity and turbulence intensity (TI) are in reasonably good agreement with the experimental results..
5. Hongzhong Zhu, Sueyoshi Makoto, Changhong Hu, Shigeo Yoshida, A study on a floating type shrouded wind turbine
Design, modeling and analysis, Renewable Energy, 10.1016/j.renene.2018.09.028, 1099-1113, 2019.04, This paper addresses a fundamental study of a floating type shrouded wind turbine on the design, mathematical model and motion analysis. Several novel concepts are introduced to the system for cost reduction: a revolute hinge is applied between the tower and the nacelle to maintain the orientation of the nacelle even in a large tower inclination, a swashplate mechanism with cyclic control is employed for blade pitch regulation to improve the system controllability, a novel mooring system with a slewing bearing is utilized to build the passive yawing system, and an advanced spar-type floater is used to obtain high restoring performance with a short spar. Firstly, the design aspects of the main components of the system are given. Then, the numerical model including the structural model, hydrodynamic/aerodynamic model, and the control system is presented. The static and dynamic responses under both the operational situation and survival conditions are finally studied. The paper illustrates the probability of the shrouded wind turbine on floating offshore application, and can provide critical information for the optimization design in next stage..
6. Mohamed M. Kamra, Jabir Al Salami, Sueyoshi Makoto, Changhong Hu, Experimental study of the interaction of dambreak with a vertical cylinder, Journal of Fluids and Structures, 10.1016/j.jfluidstructs.2019.01.015, 86, 185-199, 2019.04, The aim of this research has been to conduct experimental measurements of the dam break impact on a vertical cylinder placed over a dry horizontal bed. The work aims to emphasize the effect of cylinder cross-section on the nature of impact as well as provide accurate and comprehensive data for the validation of computational fluid dynamics(CFD) codes. The experimental setup is based on a series of experiments conducted in the Research Institute for Applied Mechanics (RIAM) between the years 2010 and 2017. The gate motion is thoroughly studied and a novel gate motion formula is proposed based on the recent experimental data. The effect of gate obstruction on the time of impact with the cylindrical obstacle is presented and correlated to the parameters of the proposed motion profile thus emphasizing its significance in the numerical modeling of dam break flow. The effect of the cross-section of the cylinder is studied by examining the pressure signal on the cylinder as well as the vertical wall downstream of the cylinder. The pressure on the wall is compared with the no-obstacle case to highlight its effect on the pressure of the downstream conditions. The square cylinder is found to experience fairly similar pressure impulse as the circular cylinder. However, the square cylinder seems to impede the flow momentum in the x-direction more than the circular case. The data-set presented in this article is provided as Supplementary Materials including gate motion measurement, pressure measurements, and high-resolution videos..
7. Cheng Liu, Changhong Hu, CFD simulation of tidal current farm by using AL model, Journal of Hydrodynamics, 10.1007/s42241-019-0010-8, 31, 1, 34-40, 2019.02, In this study, an efficient numerical method for predicting the wake interference of multiple turbines is presented. The actuator line (AL) model instead of the geometry-resolved method is adopted to represent the rotor. The Large-eddy simulation (LES) is performed to predict wakes of multiple turbines operated in turbulent flows. An efficient immersed boundary (IB) method with moving least square reconstruction (MLS) is developed to model the nacelle and support structure of the tidal turbine. A simple wall function based on the MLS-IB method and boundary-layer equations is employed to compute the instantaneous wall shear stress. Laminar flow simulations of unsteady flows past a cylinder illustrate the accuracy of the wall function IB method. Finally, the proposed method is extended to study turbulent flow past tandem tidal rotors, in which the wake profile behind rotors is analyzed. The results are found to be in reasonable agreement with published data..
8. Hao Guo, Jianhua Wang, Decheng Wan, Changhong Hu, Benchmark computations on motion responses and bow waves of the ship in regular waves, 29th International Ocean and Polar Engineering Conference, ISOPE 2019 Proceedings of the 29th International Ocean and Polar Engineering Conference, ISOPE 2019, 2871-2878, 2019.01, The bow wave depending on the bow shape can be determined by relatively simple geometric parameters due to little influence of the downstream wave. Accurate prediction of the bow wave is essential for ship resistance and motion responses. In this paper, the benchmark ship model, the Blunt modified Wigley, is used for all the simulations. The bow wave generated by the Blunt modified Wigley hull at a constant speed in incident waves is considered. The bow wave and the ship hydrodynamics are investigated by using Reynolds-averaged Navier-Stokes (RANS) method with Volume of Fluid (VOF) method to capture the free surface. In-house computational fluid dynamics solver, naoe-FOAM-SJTU, is applied to predict the hydrodynamics. The added resistance and motion responses of the Blunt modified Wigley in incident waves are studied to help understand the effect of the wave length on motion responses. The 1st harmonic amplitude and corresponding phase for heave and pitch motions are analyzed in detail. Furthermore, the wave patterns are visualized to discuss the evolution of the bow wave..
9. Xu Ning, Yang Huang, Decheng Wan, Changhong Hu, Numerical study of wake interaction and its effect on wind turbine aerodynamics based on actuator line model, 29th International Ocean and Polar Engineering Conference, ISOPE 2019 Proceedings of the 29th International Ocean and Polar Engineering Conference, ISOPE 2019, 483-490, 2019.01, Wake interaction normally occurs in all wind farms and impacts significantly the flow field and performance of downstream wind turbines. The present work aims to study the wind turbine wake interaction phenomenon through the CFD method using LES and actuator line model. The solver used in the present work is developed based on the open source C++ class library OpenFOAM, in which the PISO algorithm is applied to deal with the velocity pressure coupling problem. The simulations which consider uniform inflow condition and six different layouts are implemented to study the evolving process of the interacting wakes. From the numerical result, the interacting region of wakes contains higher level turbulent flow than the single wake. The fully developed turbulence appears the earliest in the case of tandem layout, leading to serious wake meandering in the end of computational domain. The diffusion of turbulence causes the merging of wakes, and thus the velocity is redistributed among the whole wake region. Velocity deficit caused by the wake decreases the convertible wind energy. The turbulent flow and meandering of the wake result in the multi-scale fluctuation of the aero-power curves of wind turbines downstream..
10. Xinwang Liu, Decheng Wan, Gang Chen, Changhong Hu, Wigley hull form optimization with or without bulbous bow, 29th International Ocean and Polar Engineering Conference, ISOPE 2019 Proceedings of the 29th International Ocean and Polar Engineering Conference, ISOPE 2019, 4486-4494, 2019.01, The Wigley hull is considered as the initial ship, which can be globally deformed by shifting method and locally deformed by RBF (Radial Basis Function) method to generate a bulbous bow. Two optimization cases are given. In case 1, only shifting method is used, while in case 2, shifting and RBF methods are both used. The genetic algorithm is taken to obtain two optimal ships with minimum wave drag. Further validation by CFD solver naoe-FOAM-SJTU turns out that for the hull without bulbous bow, through combination of the two methods, a hull that has a much fewer wave drag can be obtained..
11. Cheng Liu, Changhong Hu, Block-based adaptive mesh refinement for fluid–structure interactions in incompressible flows, Computer Physics Communications, 10.1016/j.cpc.2018.05.015, 232, 104-123, 2018.11, In this study, an immersed boundary (IB) approach on the basis of moving least squares (MLS) interpolation is proposed for analyzing the dynamic response of a rigid body immersed in incompressible flows. An improved mapping strategy is proposed for a quick update of the signed distance field. A CIP-CSL (constraint interpolation profile - semi-Lagrangian) scheme with a compact stencil is adopted for the convective term in momentum equation. Fluid–structure interaction problems can be solved by either the weak or the strong coupling schemes according to the density ratio of the solid and fluid. This research is based on our previous studies on block-structured adaptive mesh refinement (AMR) method for incompressible flows (Liu & Hu, 2018). Present AMR-FSI solver is proved to be accurate and robust in predicting dynamics of VIV (vortex induced vibration) problems. The efficiency of the adaptive method is demonstrated by the 2D simulation of a freely falling plate with the comparison to other numerical methods. Finally, the freely falling and rising 3D sphere are computed and compared with corresponding experimental measurement..
12. Yingyi Liu, Shigeo Yoshida, Changhong Hu, Sueyoshi Makoto, Liang Sun, Junliang Gao, Peiwen Cong, Guanghua He, A reliable open-source package for performance evaluation of floating renewable energy systems in coastal and offshore regions, Energy Conversion and Management, 10.1016/j.enconman.2018.08.012, 174, 516-536, 2018.10, The booming developments of coastal/offshore renewable energies in recent years call for a powerful numerical code, ideally open-source packaged, to accelerate the researches in the spotlight. This paper presents such an efficient software package for evaluating the performance of floating renewable energy systems in the coastal and offshore regions. It aims to contribute an open-source effort in numerical simulations for ocean energy converters. Though computation of the free-surface effect in moderate depth region is extremely troublesome due to the singularities, the software package proposed in the present paper gives a satisfactory solution to keep the balance of accuracy and efficiency. In the present paper, the interface and structure of the package are introduced in detail so as to be well understood by the reader. Benchmark tests for various types of converters have confirmed the accuracy and efficiency of the package which can be incorporated easily with a frequency domain solver for efficient analysis. By contributing as one of the pioneer works in the open-source effort of evaluating the moderate-depth free-surface Green's function, with its advantages of a reliable accuracy and a relatively low cost, the authors are hoping that the publication of the present software package will promote the continuous researches in developing robust and reliable coastal and offshore renewable energy systems..
13. Mohamed M. Kamra, Nik Mohd, Cheng Liu, Sueyoshi Makoto, Changhong Hu, Numerical and experimental investigation of three-dimensionality in the dam-break flow against a vertical wall, Journal of Hydrodynamics, 10.1007/s42241-018-0074-x, 30, 4, 682-693, 2018.08, The three-dimensionality extent of the dam break flow over a vertical wall is investigated numerically and experimentally in this paper. The numerical method is based on Reynolds averaged Navier-Stokes (RANS) equation that describes the three-dimensional incompressible turbulent flow. The free surface is captured by using the unstructured multi-dimensional interface capturing (UMTHINC) scheme. The equations are discretized on 2-D and 3-D unstructured grids using finite volume method. The numerical simulations are compared with newly conducted experiment with emphasis on the effect of three-dimensionality on both free surface and impact pressure. The comparison between the numerical and experimental results shows good agreement. Furthermore, the results also show that 3-D motion of the flow originates at the moment of impact at the lower corners of the impact wall and propagates to the inner region as time advances. The origin of the three-dimensionality is found to be the turbulence development as well as the relative velocity between the side wall region and the inner region of the wave front at the moment of impact..
14. Changhong Hu, Cheng Liu, Simulation of violent free surface flow by AMR method, Journal of Hydrodynamics, 10.1007/s42241-018-0043-4, 30, 3, 384-389, 2018.06, A novel CFD approach based on adaptive mesh refinement (AMR) technique is being developed for numerical simulation of violent free surface flows. CIP method is applied to the flow solver and tangent of hyperbola for interface capturing with slope weighting (THINC/SW) scheme is implemented as the free surface capturing scheme. The PETSc library is adopted to solve the linear system. The linear solver is redesigned and modified to satisfy the requirement of the AMR mesh topology. In this paper, our CFD method is outlined and newly obtained results on numerical simulation of violent free surface flows are presented..
15. Ping Cheng, Decheng Wan, Changhong Hu, Numerical Simulations of Flows around Floating Offshore Wind Turbine, 28th International Ocean and Polar Engineering Conference, ISOPE 2018 Proceedings of the 28th International Ocean and Polar Engineering Conference, ISOPE 2018, 414-421, 2018.06, The fully-coupled aero-hydrodynamic simulations of a floating offshore wind turbine consisting of a NREL-5MW baseline wind turbine and a semi-submersible floating platform are conducted. The three-dimensional Reynolds Averaged Navier-Stokes (RANS) equations are solved for the coupled aero-hydrodynamic numerical simulation. The in-house code naoe-FOAM-SJTU, which is based on OpenFOAM and overset grid technology and developed for ship and ocean engineering, is employed. Aerodynamic loads on wind turbine are predicted. With the directly viscous simulations, detailed flow information around the turbine blades is available. The coupling effect on the aerodynamics of wind turbine from the platform motion is investigated..
16. Xinze Duan, Ping Cheng, Decheng Wan, Changhong Hu, Numerical Simulations of Wake Flows of Wind Farm with Fourteen Wind Turbines, 28th International Ocean and Polar Engineering Conference, ISOPE 2018 Proceedings of the 28th International Ocean and Polar Engineering Conference, ISOPE 2018, 519-526, 2018.06, The wake interaction phenomenon among wind turbines has a great influence on aerodynamic power output, wind speed deficit turbulence stress and wake vortex structure, which indicates that more attention should be placed on the wake interaction for the optimal arrangement of wind farm. In this present study, firstly a numerical validation of aerodynamics for the two offset model wind turbines using actuator line model and CFD technique. The results obtained from the present simulations are compared to the data from the experiment “Blind Test 3” and other simulation models. Based on the simulations results, the present study shows good agreement with the experimental results. Then considering the uniform inflow condition, the complex phenomenon of wake interaction in wind farm containing fourteen wind turbines is simulated using a numerical method. Large eddy simulations combined with an actuator line model are conducted in the in-house CFD code FOWT-UALM-SJTU Solver. The motivation for this work is to create a sound methodology for performing the simulation of large wind farms. To better understand the wake interaction phenomenon, the aerodynamic power coefficients and basic features of both the near and far wake, including the distribution characteristics of the mean wake velocity and vortex structures are studied in detail..
17. Yang Huang, Decheng Wan, Changhong Hu, Numerical Study of Wake Interactions between Two Floating Offshore Wind Turbines, 28th International Ocean and Polar Engineering Conference, ISOPE 2018 Proceedings of the 28th International Ocean and Polar Engineering Conference, ISOPE 2018, 541-548, 2018.06, The wake interaction between floating offshore wind turbines (FOWTs) has a significant effect on the FOWT's power output, system dynamics responses and structural loadings. To better understand the wake interaction phenomenon in floating wind farms, fully coupled simulations considering the coupling effects between the wind turbine, floating platform and mooring system for FOWTs are necessary. In the present paper, the unsteady actuator line model (UALM) is embedded into in-house CFD solver naoe-FOAM-SJTU to establish a fully coupled CFD analysis tool named FOWT-UALM-SJTU for numerical simulations of FOWTs. Coupled aero-hydrodynamic simulations of two OC3 Hywindspar FOWT models in tandem layout under shear wind and regular wave conditions are performed using this tool. The unsteady aerodynamics of wind turbines are given by the UALM, and the hydrodynamic responses of floating platforms and mooring tensions are predicted by naoe-FOAM-SJTU. From the simulations, unsteady aerodynamic characteristics can be extracted including the rotor power and thrust as well as detailed wake flow information, and hydrodynamic responses such as the six-degree-of-freedom motions and mooring tensions are also available. Moreover, the influence of wake interaction on the performance of FOWTs is studied. It can be found that strong wake interaction phenomenon is observed and the unsteady aero-hydrodynamic responses of downstream FOWT system are greatly affected by the wake interaction..
18. Zhenghao Liu, Decheng Wan, Changhong Hu, Numerical investigation of regular waves interaction with two fixed cylinders in tandem arrangement, ASME 2018 37th International Conference on Ocean, Offshore and Arctic Engineering, OMAE 2018 Ocean Engineering, 10.1115/OMAE201878373, 2018.06, The interaction of waves with fixed or floating structures involves complex wave radiation, wave diffraction and free surface deformation. In this work, the interaction of waves with a pair of cylinders in tandem arrangement is investigated using a numerical wave tank. The numerical simulation is first validated by comparing numerical results and experimental data for regular wave interaction with a single cylinder. Wave interaction with tandem cylinders is investigated for different center-to-center distances between the cylinders. All the numerical simulations are carried out by the in-house CFD solver naoe-FOAM-SJTU which is developed on the open source platform OpenFOAM. The incompressible unsteady Reynolds averaged Navier-Stokes (URANS) equations are adopted as the governing equations. The volume of fluid (VOF) method is applied to capture the free surface. The surface elevation around the cylinders is probed by a series of wave gauges and analyzed using transfer function. The wave forces of upstream and downstream cylinder are discussed in detail. The wave forces experienced by the tandem cylinders is highly influenced by the distance between the cylinders. The local surface elevation and the scattered wave field around the cylinders are also investigated. The results show that the present CFD solver can be an alternative tool to deal with wave-structure interactions..
19. Cheng Liu, Changhong Hu, An adaptive multi-moment FVM approach for incompressible flows, Journal of Computational Physics, 10.1016/j.jcp.2018.01.006, 359, 239-262, 2018.04, In this study, a multi-moment finite volume method (FVM) based on block-structured adaptive Cartesian mesh is proposed for simulating incompressible flows. A conservative interpolation scheme following the idea of the constrained interpolation profile (CIP) method is proposed for the prolongation operation of the newly created mesh. A sharp immersed boundary (IB) method is used to model the immersed rigid body. A moving least squares (MLS) interpolation approach is applied for reconstruction of the velocity field around the solid surface. An efficient method for discretization of Laplacian operators on adaptive meshes is proposed. Numerical simulations on several test cases are carried out for validation of the proposed method. For the case of viscous flow past an impulsively started cylinder (Re=3000,9500), the computed surface vorticity coincides with the result of the body-fitted method. For the case of a fast pitching NACA 0015 airfoil at moderate Reynolds numbers (Re=10000,45000), the predicted drag coefficient (CD) and lift coefficient (CL) agree well with other numerical or experimental results. For 2D and 3D simulations of viscous flow past a pitching plate with prescribed motions (Re=5000,40000), the predicted CD, CL and CM (moment coefficient) are in good agreement with those obtained by other numerical methods..
20. Cheng Liu, Changhong Hu, An immersed boundary solver for inviscid compressible flows, International Journal for Numerical Methods in Fluids, 10.1002/fld.4399, 85, 11, 619-640, 2017.12, In this paper, a simple and efficient immersed boundary (IB) method is developed for the numerical simulation of inviscid compressible Euler equations. We propose a method based on coordinate transformation to calculate the unknowns of ghost points. In the present study, the body-grid intercept points are used to build a complete bilinear (2-D)/trilinear (3-D) interpolation. A third-order weighted essentially nonoscillation scheme with a new reference smoothness indicator is proposed to improve the accuracy at the extrema and discontinuity region. The dynamic blocked structured adaptive mesh is used to enhance the computational efficiency. The parallel computation with loading balance is applied to save the computational cost for 3-D problems. Numerical tests show that the present method has second-order overall spatial accuracy. The double Mach reflection test indicates that the present IB method gives almost identical solution as that of the boundary-fitted method. The accuracy of the solver is further validated by subsonic and transonic flow past NACA2012 airfoil. Finally, the present IB method with adaptive mesh is validated by simulation of transonic flow past 3-D ONERA M6 Wing. Global agreement with experimental and other numerical results are obtained..
21. Hongzhong Zhu, Sueyoshi Makoto, Changhong Hu, Shigeo Yoshida, Modelling and attitude control of a shrouded floating offshore wind turbine with hinged structure in extreme conditions, Proc. 6th IEEE International Conference on Renewable Energy Research and Applications (ICRERA 2017) , 10.1109/DISTRA.2017.8191162, 762-767, 2017.12, This paper addresses the modeling and attitude control of a novel shrouded floating wind turbine with hinged structure in harsh environmental conditions. Firstly, SimMechanics™ is applied to model the mechanical components of the wind turbine system. Secondly, the wave- and wind- loads acting on the system are respectively calculated based on Morison's equation and blade element momentum theory. Controllers of the elevator and the rudder located at the upwind side are designed based on linearized models to enhance the stability of the system. Numerical examples with three extreme weather conditions are finally performed to verify the effectiveness of the controllers. The results demonstrate that the pitching motion of the nacelle can be regulated to be within 3 degrees in the examples. In addition, the wind turbine could yaw itself stably toward the wind direction..
22. Cheng Liu, Changhong Hu, A Second Order Ghost Fluid Method for an Interface Problem of the Poisson Equation, Communications in Computational Physics, 10.4208/cicp.OA-2016-0155, 22, 4, 965-996, 2017.10, A second order Ghost Fluid method is proposed for the treatment of interface problems of elliptic equations with discontinuous coefficients. By appropriate use of auxiliary virtual points, physical jump conditions are enforced at the interface. The signed distance function is used for the implicit description of irregular domain. With the additional unknowns, high order approximation considering the discontinuity can be built. To avoid the ill-conditioned matrix, the interpolation stencils are selected adaptively to balance the accuracy and the numerical stability. Additional equations containing the jump restrictions are assembled with the original discretized algebraic equations to form a new sparse linear system. Several Krylov iterative solvers are tested for the newly derived linear system. The results of a series of 1-D, 2-D tests show that the proposed method possesses second order accuracy in L norm. Besides, the method can be extended to the 3-D problems straightforwardly. Numerical results reveal the present method is highly efficient and robust in dealing with the interface problems of elliptic equations..
23. Nik Mohd, Mohamed M. Kamra, Sueyoshi Makoto, Changhong Hu, Lattice boltzmann method for free surface impacting on vertical cylinder: A comparison with experimental data, Evergreen, 4, 1, 28-37, 2017.09, The purpose of the present research is to study three-dimensional lattice Boltzmann method (LBM) simulation on free surface impact phenomena with the validation on a newly performed dam breaking experiment. Large eddy simulation (LES) is implemented in the LBM to enhance the computational efficiency and to relax the restriction of the computational stability. The LBM method involves a surface-tracking technique with free surface algorithm. In this study, the present numerical simulation is validated by comparing wave front propagation and water level elevation with the experimental measurements. A three dimensional numerical simulation on dam breaking with vertical cylinder obstacles are performed and qualitative comparison with the experimental measurement has been made. Good qualitative agreement between numerical simulations and the experiments has been obtained in terms of free surface development, splash pattern and splash distance. For the square cross section cylinder, the water impacts on the cylinder violently and the flow is directed to the sides of the tank. For the circular cross section cylinder, the water flows smoothly around the cylinder and impacts tank wall violently. The results show that the free surface lattice Boltzmann method is efficient for dealing with complex geometrical problems..
24. Mohamed M. Kamra, Changhong Hu, Implementation of Unstructured Multi-dimensional THINC for Practical Multi-Phase Flow Simulations, Evergreen, 4, 1, 52-57, 2017.09, The purpose of the present research is to study three-dimensional lattice Boltzmann method (LBM) simulation on free surface impact phenomena with the validation on a newly performed dam breaking experiment. Large eddy simulation (LES) is implemented in the LBM to enhance the computational efficiency and to relax the restriction of the computational stability. The LBM method involves a surface-tracking technique with free surface algorithm. In this study, the present numerical simulation is validated by comparing wave front propagation and water level elevation with the experimental measurements. A three dimensional numerical simulation on dam breaking with vertical cylinder obstacles are performed and qualitative comparison with the experimental measurement has been made. Good qualitative agreement between numerical simulations and the experiments has been obtained in terms of free surface development, splash pattern and splash distance. For the square cross section cylinder, the water impacts on the cylinder violently and the flow is directed to the sides of the tank. For the circular cross section cylinder, the water flows smoothly around the cylinder and impacts tank wall violently. The results show that the free surface lattice Boltzmann method is efficient for dealing with complex geometrical problems..
25. Cheng Liu, Changhong Hu, Adaptive THINC-GFM for compressible multi-medium flows, Journal of Computational Physics, 10.1016/j.jcp.2017.04.032, 342, 43-65, 2017.08, In this paper, a THINC (tangent of hyperbola for interface capturing) (Xiao F. et al., 2005) [26] coupled with GFM (Ghost Fluid Method) is proposed for numerical simulation of compressible multi-medium flows. The THINC scheme, which was first developed for incompressible flows, is applied for capturing the distorted material interface of compressible flows. The hybrid WENO (weighted essentially non-oscillatory) scheme with the blocked structured adaptive mesh refinement (AMR) method is implemented. Load balancing is considered in the parallel computing. Several well documented numerical tests are performed and the results show that the THINC scheme behaviors better in mass conservation. It is the first endeavor to implement THINC scheme with adaptive mesh for computing the compressible multiphase problems. The shock wave–helium bubble interaction test reveals that the present method is efficient in prediction of the deformed interface. The solver is further validated by shock wave impact SF6 interface with square, rectangle, forward and backward triangle shapes in which the wave positions and intersecting angles are compared quantitatively. Finally, the collapse of an air bubble under shock in water is simulated, global agreement with experimental and other numerical results are obtained..
26. Yang Huang, Decheng Wan, Changhong Hu, Coupled aero-hydrodynamic analysis on a floating offshore wind turbine under extreme sea conditions, Proceedings of the 27th International Ocean and Polar Engineering Conference (ISOPE 2017), 395-402, 2017.06, To develop renewable energy, the offshore wind energy technology has become an attractive research field. Considering the coupling effect of the platform motions and aerodynamic loads, how to accurately simulate the aero-hydrodynamics of floating offshore wind turbine is important. In this paper, an unsteady actuator line model (UALM) coupled with a two-phase CFD solver called naoe-FOAM-SJTU is applied to solve the three-dimensional Navier-Stokes equations to focus on the coupled dynamic responses of an aerodynamics-hydrodynamics-mooring system for a floating offshore wind turbine named OC3-HywindSpar under extreme sea conditions. Response characteristics including the thrust and the rotor power of the wind turbine, the motions of the platform and the mooring loads under different extreme sea states are carefully compared to study the influence of the wind speed and the wave height on the floating offshore wind turbine. Furthermore, several conclusions are drawn based on the comparison results..
27. Yong Ai, Decheng Wan, Changhong Hu, Effects of inter-turbines spacing on aerodynamics for wind farms based on actuator line model, Proceedings of the 27th International Ocean and Polar Engineering Conference (ISOPE 2017), 386-394, 2017.06, Among several wind farm layout design parameters, the inter-turbine spacing, which has a great influence on aerodynamic power output, wind speed deficit, lifetime, wake vortex structure, is one of the most critical factors. Therefore, the effects of inter-turbine spacing on aerodynamics for wind farms must be carefully studied. In this study, Considering the uniform inflow conditions, the effects of inter-turbine spacing changing from three to nine times of rotor diameter on aerodynamics for wind farms containing two NREL 5MW baseline wind turbines in tandem layout are analyzed using actuator line model and CFD method, and the RANS equation with k-ω SST turbulence model was solved in the simulations conducted in the OpenFOAM. From the study, it is concluded that the inter-turbine spacing has significant effects on the aerodynamic power and wake characteristics. The aerodynamic power output of the downstream wind turbine exits sharp fluctuation before power output of the downstream wind turbine is becoming steady. Furthermore, periodic oscillation whose period is about the one-third of rotor rotating period can be also concluded from the study. Moreover, there is strong wake interaction which will impact the aerodynamics for wind farms seriously..
28. Kangping Liao, Wenyang Duan, Qingwei Ma, Shan Ma, Binbin Zhao, Changhong Hu, Numerical analysis of wave impact loads on semi-submersible platform, ASME 2017 36th International Conference on Ocean, Offshore and Arctic Engineering, OMAE 2017, 10.1115/OMAE2017-62464, Paper No.: OMAE2017-62464, 2017.06, In rough sea conditions, semi-submersible platform often suffers from extreme wave impact loads, which can result in structural damage. It is important to predict the wave impact loads on semi-submersible platform. Therefore, the purpose of this study is to investigate the wave impact loads on semisubmersible platform with numerical methods. A numerical method, based on a fixed regular Cartesian grid system, has been developed by the authors. In the method, the FDM (Finite Difference Method) is applied for solving flow field, and the THINC/SW (Tangent of Hyperbola for INterface Capturing with Slope Weighting) model, which is kind of VOF (Volumeof- Fluid) model, is adopted to capture the free surface. Some selected model test cases, form Exwave JIP project, will be used to validate the present numerical method and to analyze the wave impact loads on semi-submersible platform..
29. Mohamed M. Kamra, Changhong Hu, Numerical simulation of free surface impact on a vertical cylinder using UMTHINC, Proceedings of the 27th International Ocean and Polar Engineering Conference (ISOPE 2017), 301-307, 2017.06, When considering flows with multiple fluids such as free surface flow and multiphase flow, an interface tracking scheme or an interface capturing scheme is required for treatment of the interfaces. The latter is more popular with CFD community due to its adaptability to different flow structures and different kinds of grids as well as its good computational efficiency. The THINC scheme is an interface capturing scheme which was originally developed for use with Cartesian grid flow solvers. Since the method provides an algebraic model for the transition between different fluids it becomes relatively easy to compute the convective fluxes which is the target of advection schemes. In this work, we apply an unstructured grid extension of the THINC scheme, UMTHINC scheme, to our newly developed unstructured grid flow solver for free surface impact problems. The efficiency and accuracy of the proposed method is investigated by applying it to some standard benchmark cases on dam break problem with an obstacle. Both two and three dimensional simulations are carried out and the results are compared to experimental data wherever possible..
30. Yingyi Liu, Changhong Hu, Sueyoshi Makoto, Hidetsugu Iwashita, Masashi Kashiwagi, Erratum to
Motion response prediction by hybrid panel-stick models for a semi-submersible with bracings (Journal of Marine Science and Technology, (2016), 21, 4, (742-757), 10.1007/s00773-016-0390-1), Journal of Marine Science and Technology (Japan), 10.1007/s00773-016-0427-5, 22, 2, 401-402, 2017.06, In the original publication of this paper, Fig. 4 was incorrectly published. The corrected version is given in this erratum. (Figure Presented.)..
31. Nik Mohd, Mohamed M. Kamra, Sueyoshi Makoto, Changhong Hu, Three-dimensional free surface flows modeled by lattice boltzmann method
A comparison with experimental data, Evergreen, 4, 1, 29-35, 2017.03, Three-dimensional numerical simulations of strongly nonlinear free surface flows are performed by lattice Boltzmann method (LBM), which features a number of performance-related advantages, particularly concerning data locality and parallel computing. A Multi-Passage-Interface (MPI) multicore processors parallelized free surface LBM solver is applied for the present three-dimensional numerical simulations. A Smagorinsky LES turbulent model serves to capture the small-scale turbulent structures of the flow. Experiments on dam breaking from previous articles are used to compare and verify two-dimensional (2D) and three-dimensional (3D) LBM model. A new experimental setup is also developed in order to observe the three-dimensionality effect. The findings demonstrated that the free surface LBM simulation agrees well with the experiments..
32. Mohamed M. Kamra, Changhong Hu, Implementation of unstructured multi-dimensional THINC for practical multi-phase flow simulations, Evergreen, 4, 1, 52-57, 2017.03, This work presents an application of the Unstructured Multi-dimensional Tangent Hyperbolic Interface Capturing (UMTHINC), volume of fluid, scheme for the multi-phase solution of free surface flows on unstructured mesh. The applicability of the UMTHINC to practical engineering problems with interfacial multiphase flow is investigated and the accuracy of the results are reported. The UMTHINC is integrated into an in-house unstructured incompressible flow solver and used as an engine to capture the moving interface. The well-known dam break problems with and without an obstacle are used to evaluate the accuracy and performance of the scheme. This work is limited to two dimensional cases with no turbulence modeling. The relationship between the sharpness parameter β, and CFL number is examined and reported. The results are well analyzed and compared to experimental data wherever possible. The results show that the UMTHINC interface capturing method is able to accurately capture the interface without the complexity and computation cost of the geometrical reconstruction method..
33. Yingyi Liu, Changhong Hu, Makoto Sueyoshi, Hidetsugu Iwashita, Masashi Kashiwagi, Motion response prediction by hybrid panel-stick models for a semi-submersible with bracings, Journal of Marine Science and Technology, 10.1007/s00773-016-0390-1, 21, 742-757, 2016.12.
34. Changhong Hu, Cheng Liu, Development of Cartesian Grid Method for Simulation of Violent Ship-Wave Interactions, Journal of Hydrodynamics, 10.1016/S1001-6058(16)60702-3, 28, 6, 1003-1010, 2016.12.
35. Jinghong Shang, Yuna Zhao, Liang Zhang, Changhong Hu, Xiaomeng Ding, Coupled method for predicting motions of Spar-type offshore floating wind turbine systems, Harbin Gongcheng Daxue Xuebao/Journal of Harbin Engineering University, 10.11990/jheu.201510073, 37, 9, 1163-1171, 2016.09, In this study, we established non-linear time-domain coupled dynamic equations and aero/hydro-dynamical models to study the interaction between wind waves and floating offshore turbine systems (FOWTs). We used Fortran code, time-frequency domain transformation, and the Runge-Kutta iteration method to solve nonlinear equations. We analyzed the 5DOF motion response characteristics of Spar FOWTs, except yawing, under steady wind wave, regular wave, and random wind-wave conditions. The results show that constant wind affects the average and peak-to-peak values of surge, pitch, heave, sway, and roll at the rated wind speeds, while it does not affect the peak-to-peak values of sway at other wind speeds. In addition, regular waves have only marginal effect on the average values of surge, pitch, heave, sway, and roll, but enlarge their peak-to-peak values. Under random wind and wave conditions, we characterized the system's sway and pitch motions for low and high wave frequencies, depending on the wind speed. The results of this study provide references for the design and hydrodynamic analysis of offshore floating wind turbine systems..
36. Hongzhong Zhu, Changhong Hu, and Yingyi Liu, Optimum Design of a Passive Suspension System of a Semisubmersible for Pitching Reduction, Journal of Dynamic Systems, Measurement, and Control, 10.1115/1.4033948, 138, 12, Paper No: DS-16-1048, 2016.06.
37. Hongzhong Zhu, Changhong Hu, Yingyi Liu, Kangping Liao, Suspension design of a semi-submersible platform, Proc. ASME 2016 35th International Conference on Ocean, Offshore and Arctic Engineering (OMAE 2016) , 10.1115/OMAE2016-54347, 7, 2016.06, With the development of ocean energy exploration, reliable and low cost semi-submersible platforms are expected to develop. The maximum pitching amplitude of a floater for floating offshore wind turbine should be less than a few degrees to avoid fatigue failure. In this paper, a novel conceptual design of a new type semi-submersible with suspensions for suppressing the pitch motion is presented. Many wave energy dissipation devices, such as add-onwave energy converters to a floating platform, could be regarded as the suspension system in our design. Firstly, linear models are applied to approximate the radiation forces and wave exciting forces so that the whole motion system is represented by a state-space model. Then, we show that design of suspensions leads to synthesize a controller via solving a constrained H∞ optimization problem. Finally, numerical examples are performed to verify the design and it can be shown that the pitch motion of the semi-submersible platform is remarkably reduced..
38. Ping Cheng, Decheng Wan, Changhong Hu, Unsteady aerodynamic simulations of floating offshore wind turbines with overset grid technology, Proceedings of the 26th International Ocean and Polar Engineering Conference (ISOPE 2016), 391-398, 2016.06, The aerodynamic performance of the floating offshore wind turbine has an extra level of complexity than that of bottom-fixed wind turbines because of the motions of the supporting platform. In this paper, the unsteady aerodynamic performance of the NREL-5MW Baseline wind turbine with periodical surge and pitch motions of its supporting platform are investigated. The three-dimensional Reynolds Averaged Navier-Stokes equations are solved for the aerodynamic numerical simulation. The naoe-FOAM-os-SJTU solver, which is based on OpenFOAM and overset grid technology and developed for ship and ocean engineering problems, is employed. From the simulation, the time series of the unsteady torque and thrust are obtained, together with the detailed information of the wake flow field, and the pressure coefficient distribution in different cross-section are also available to clarity the detailed flow filed information. The simulation results are compared both with those obtained from aerodynamic simulation of wind turbine without effects of platform motions, and with other approaches in previous studies. The simulation results show that the pitch motion has more significant effects on the aerodynamic forces and moments of the rotor than the surge motion does. And the motion of the platform especially the pitch motion may bring very bad influence on the turbine forces and wake flow, even on the power generation in case of very severe pitch motion..
39. Xuhui Li, Fei Jiang, Changhong Hu, Analysis of the accuracy and pressure oscillation of the lattice Boltzmann method for fluid–solid interactions, Computers & Fluids, 10.1016/j.compfluid.2016.01.015, 129, 33-52, 2016.04, Investigations have been conducted to analyze the accuracy of the ghost fluid immersed boundary lattice Boltzmann method and the conventional interpolation/extrapolation bounce-back schemes. The intrinsic sources of pressure oscillation for numerical simulation of moving boundary flows have also been inves- tigated. An existing bilinear ghost fluid immersed boundary lattice Boltzmann method (BGFM) (Tiwari and Vanka, 2012) and a proposed quadratic ghost fluid immersed boundary lattice Boltzmann method (QGFM) have been compared with Guo’s second-order extrapolation bounce-back scheme (Guo et al.) and the linear and quadratic interpolation bounce-back scheme (LIBB, QIBB) (Bouzidi et al., 2001; Lalle- mand and Luo, 2003). To study the numerical pressure oscillations in the moving boundary problem, (i) three existing refilling techniques and one proposed refilling technique are compared; (ii) three col- lision models, including the single-relaxation-time model, the multiple-relaxation-time model and the two-relaxation-time model, are investigated; (iii) two force evaluation schemes, a Galilean invariant mo- mentum exchange method Wen et al. and a stress integration method Inamuro et al., are considered. The accuracy and the performance in pressure oscillation suppression for the studied numerical approaches are compared and discussed by five numerical examples: an eccentric cylinder flow, a Cylindrical Couette flow, an impulsively started cylinder in a channel, an oscillation cylinder in calm water and a particle suspension problem. The numerical results indicate that the accuracy of QGFM scheme is comparable to Guo’s scheme while the accuracy of BGFM is worse than both of them. The QIBB scheme shows the best performance in the space convergence accuracy among all the schemes. Selection of the collision model, refilling technique and force evaluation scheme affect the pressure oscillation phenomenon in moving boundary simulations remarkably..
40. Hongzhong Zhu, Changhong Hu, A Study on Control of Wave Energy Converter for Motion Suppression of Semisubmersible, IFAC-PapersOnLine, 10.1016/j.ifacol.2016.10.434, 49, 23, 380-385, 2016.01, With the development of ocean energy exploration, reliable floating platforms with very small motion are expected to develop. For instance, the maximum pitching amplitude of a floater for floating offshore wind turbine is required to be less than a few degrees. On the other hand, ocean waves contain abundance of untapped renewable energy with very high power density. Integration of floating platform with wave energy converters while reducing the structure interaction becomes significant for offshore development. In this paper, control of wave energy converters on reducing the pitch motion of a floating platform is studied. Firstly, mathematical model of the whole system is proposed. The control of wave energy converters leads to solve a constrained optimization problem. Secondly, hybrid model predictive control is presented to synthesize the controller. Finally, numerical examples are given to verify the effectiveness of the proposed controller. It is shown that the reduction of pitch motion of the platform and the wave energy extraction are compatible..
41. Pengfei Li, Decheng Wan, Changhong Hu, Fully-coupled dynamic response of a semi-submerged floating wind turbine system in wind and waves, 26th Annual International Ocean and Polar Engineering Conference, ISOPE 2016 Proceedings of the 26th International Ocean and Polar Engineering Conference, ISOPE 2016, 273-281, 2016.01, An Unsteady Actuator Line Model (UALM) is developed in this paper and applied to a 5MW floating offshore wind turbine (FOWT). This model is implemented into two-phase fluid CFD solver, naoeFOAMSJTU. The goal of the approach presented here is to investigate the interaction of the aerodynamic loads with the platform motion within acceptable time cost. A semi-submerged floating platform conceptualized in the Offshore Code Comparison Collaboration (OC4) is considered in this paper. Initially the UALM is verified by comparison with the results of a previous study. Next, two kind of fullsystem simulations with different complexity are performed: first, the wind forces are simplified into a constant thrust; second, the fully coupled dynamic analysis with wind and wave excitation is conducted by utilizing UALM. Based on the results, the aerodynamic loads and coupled responses for cases of different complexity are discussed..
42. Changhong Hu, Cheng Liu, Development and Validation of RANS CFD Model for Hydrodynamic Prediction of a Horizontal Tidal Current Turbine, Proceedings of the 11th European wave and tidal conference, Paper No.: 09B2-2, 2015.09.
43. Cheng Liu, Changhong Hu, CFD Prediction of the Hydrodynamic Performance of a Horizontal Tidal Current Turbine, Proceedings of the ASME 2015 34th International Conference on Ocean, Offshore and Arctic Engineering, Paper No.: OMAE2015-41776, 2015.06.
44. Yingyi Liu, Changhong Hu, Sueyoshi Makoto, Hidetsugu Iwashita, Hydrodynamic Analysis of a Semi-Submersible FOWT by Hybrid Panel-Stick Models, Proceedings of the 25th International Offshore and Polar Engineering Conference, 1, 340-345, 2015.06.
45. Zhaoyu Wei, Changhong Hu, Experimental study on water entry of circular cylinders with inclined angles, Journal of Marine Science and Technology, 10.1007/s00773-015-0326-1, 20, 722-738, 2015.06.
46. Yingyi Liu, Hidetsugu Iwashita, Changhong Hu, A Calculation Method for Finite Depth Free-Surface Green Function, International Journal of Naval Architecture and Ocean Engineering, 7, 2, 375-389, 2015.03.
47. Kangping Liao, Changhong Hu, Free surface flow impacting on an elastic structure: Experiment versus numerical simulation, Applied Ocean Research, 10.1016/j.apor.2015.02.002, 50, 192-208, 2015.03.
48. Yingyi Liu, Hidetsugu Iwashita, Changhong Hu, A calculation method for finite depth Free-Surface green function, International Journal of Naval Architecture and Ocean Engineering, 10.1515/ijnaoe-2015-0026, 7, 2, 375-389, 2015.01, An improved boundary element method is presented for numerical analysis of hydrodynamic behavior of marine structures. A new algorithm for numerical solution of the finite depth free-surface Green function in three dimensions is developed based on multiple series representations. The whole range of the key parameter R/h is divided into four regions, within which different representation is used to achieve fast convergence. The well-known epsilon algorithm is also adopted to accelerate the convergence. The critical convergence criteria for each representation are investigated and provided. The proposed method is validated by several well-documented benchmark problems..
49. Yingyi Liu, Changhong Hu, Makoto Sueyoshi, Hidetsugu Iwashita, Hydrodynamic analysis of a semi-submersible FOWT by hybrid panel-stick models, 25th International Ocean and Polar Engineering Conference, ISOPE 2015 Proceedings of the 25th International Ocean and Polar Engineering Conference, ISOPE 2015, 340-345, 2015.01, A diffraction-radiation analysis is usually required when the hydrodynamic interactions between structural members occur in short waves. For bracings or small cylinder members, which play important roles in the vicinity of the natural frequency of a floating platform, special care should be taken into account for the effect of viscous damping. Two hybrid panel-stick models are therefore developed, through the combination of the standard diffraction-radiation method and the Morison's formulae, while considering the effect of small members differently. The fluid velocity is obtained directly by the panel model. The viscous fluid force is calculated for individual members by the stick model. A semi-submersible type platform with a number of fine cylindrical structures, which is designed as a floating foundation for multiple wind turbines, is analysed as a numerical example. The results show that viscous force has large influence on the behaviour of the floating body and can successfully be considered by the proposed hybrid models..
50. Changhong Hu, Sueyoshi Makoto, Cheng Liu, Yingyi Liu, Hydrodynamic Analysis of a Semi-Submersible-Type Floating Wind Turbine, Journal of Ocean and Wind Energy , 1, 4, 202-208, 2014.11.
51. Cheng Liu, Changhong Hu, An Efficient Immersed Boundary Treatment for Complex Moving Object, Journal of Computational Physics, 10.1016/j.jcp.2014.06.042, 274, 654-680, 2014.10.
52. Zhaoyu Wei, Changhong Hu, An experimental study on water entry of horizontal cylinders, Journal of Marine Science and Technology, 10.1007/s00773-013-0252-z, 19, 3, 338-350, 2014.09.
53. Fei Jiang, Takeshi Tsuji, Changhong Hu, Elucidating the role of interfacial tension for hydrological properties of two-phase flow in natural sandstone by an improved lattice Boltzmann method, Transport in Porous Media, 10.1007/s11242-014-0329-0, 104, 1, 205-229, 2014.08.
54. Kangping Liao, Changhong Hu, Sueyoshi Makoto, Wave Energy Converter as an Anti-motion Device for Floating Offshore Wind Turbine, Proc. GRAND RENEWABLE ENERGY 2014, Paper No.: O-Oc-8-2, 2014.07.
55. Changhong Hu, Sueyoshi Makoto, Yusaku kyozuka, Shigeo Yoshida, Yuji Ohya, Development of New Floating Platform for Multiple Ocean Renewable Energy, Proc. GRAND RENEWABLE ENERGY 2014, Paper No.: O-Oc-20-4, 2014.07.
56. Yusaku kyozuka, Sueyoshi Makoto, Changhong Hu, Yuji Ohya, Demonstration Experiment of Offshore Wind Power Generation by a Hexagonal Floating Platform in Hakata Bay, Proc. GRAND RENEWABLE ENERGY 2014, Paper No.: O-WdOc-3-3, 2014.07.
57. Yingyi Liu, Changhong Hu, Shigeo Yoshida, Sueyoshi Makoto, Yuji Ohya, Development of an Integrated Analysis Tool for Semi-Submersible Floating Offshore Wind Turbine System, Proc. GRAND RENEWABLE ENERGY 2014, Paper No.: O-WdOc-3-8, 2014.07.
58. Yingyi Liu, Changhong Hu, Makoto Sueyoshi, Shigeo Yoshida, Yuichijiro Honda, Yuji Ohya, Time domain simulation of a semi-submersible type floating wind turbine, Proceedings of the 24th International Offshore and Polar Engineering Conference, 1, 288-293, 2014.06.
59. Cheng Liu, Changhong Hu, CFD Simulation of a Floating Wind Turbine Platform in Rough Sea Conditions, Proceedings of the 24th International Offshore and Polar Engineering Conference, 1, 325-329, 2014.06.
60. Fei Jiang, Changhong Hu, Numerical Simulation of a Rising CO2 Droplet in the Initial Accelerating Stage by a Multiphase Lattice Boltzmann Method, Applied Ocean Research, 10.1016/j.apor.2013.06.005, 45, 0, 1-9, 2014.03, A multi-phase flow model which applies lattice Boltzmann method (LBM) is developed for numerical simulation
of the initial accelerating stage of a rising CO 2 droplet in the deep ocean. In the present LBM model, a
multiple-relaxation time (MRT) collision operator is adopted to increase the numerical stability, and a color
model is used to treat the two-phase fluid. A domain shift scheme is proposed to make the long distance
calculation available. The computation is accelerated by using the GPU computing and correspondent parallel
implementation techniques are developed. The proposed numerical model is first validated against several
benchmark problems: Laplace law test, binary Poiseuille flow problem and rise of a toluene droplet. Then
numerical simulation of a liquid CO 2 droplet rising from quiescence to its steady state is carried out and the
results are compared to a laboratory experiment. Excellent agreement is obtained on both terminal velocity
and variation of droplet shape..
61. Qiang Liu, Wei Xie, Wenyang Duan, Changhong Hu, Numerical Simulation of Flow around a Cylinder under Different Reynolds Number, Applied Mechanics and Materials, 10.4028/www.scientific.net/AMM.543-547.434, 543-547, 434-440, 2014.03.
62. Zhaoyu Wei, Changhong Hu, The plunging cavities formed by the impinged jet after the entry of a sphere into water, Journal of Visualization, 10.1007/s12650-013-0194-x, 17, 1, 1-3, 2014.02.
63. Zhaoyu Wei, Changhong Hu, The plunging cavities formed by the impinged jet after the entry of a sphere into water, Journal of Visualization, 10.1007/s12650-013-0194-x, 17, 1, 1-3, 2014.02.
64. Changhong Hu, Makoto Sueyoshi, Cheng Liu, Yusaku Kyozuka, Yuji Ohya, Numerical and Experimental Study on a Floating Platform for Offshore Renewable Energy, Proceedings of the ASME 2012 32th International Conference on Ocean, Offshore and Arctic Engineering, CD-ROM, Paper No.: OMAE2013-11133, 2013.06.
65. Changhong Hu, Kangping Liao, Wenyang Duan, CFD Simulation of Flexible Ship in Regular Head Waves, Proceedings of the ASME 2012 32th International Conference on Ocean, Offshore and Arctic Engineering, CD-ROM, Paper No.: OMAE2013-11132, 2013.06.
66. Cheng Liu, Changhong Hu, CFD Simulation of a Catenary Moored Floating Wind Turbine Platform in Large Waves, Proceedings of the 27th Conference on Computational Engineering and Science, CD-ROM, 2013.06.
67. Kangping Liao, Changhong Hu, Wenyang Duan, Two-dimensional numerical simulation of an elastic wedge water entry by a coupled FDM-FEM method, Journal of Marine Science and Application, 10.1007/s11804-013-1181-2, 12, 2, 163-169, 2013.06, Hydroelastic behavior of an elastic wedge impacting on calm water surface was investigated. A partitioned approach by coupling finite difference method (FDM) and finite element method (FEM) was developed to analyze the fluid structure interaction (FSI) problem. The FDM, in which the Constraint Interpolation Profile (CIP) method was applied, was used for solving the flow field in a fixed regular Cartesian grid system. Free surface was captured by the Tangent of Hyperbola for Interface Capturing with Slope Weighting (THINC/SW) scheme. The FEM was applied for calculating the structural deformation. A volume weighted method, which was based on the immersed boundary (IB) method, was adopted for coupling the FDM and the FEM together. An elastic wedge water entry problem was calculated by the coupled FDM-FEM method. Also a comparison between the current numerical results and the published results indicate that the coupled FDM-FEM method has reasonably good accuracy in predicting the impact force..
68. Kangping Liao, Changhong Hu, A coupled FDM–FEM method for free surface flow interaction with thin elastic plate, Journal of Marine Science and Technology, 10.1007/s00773-012-0191-0, 18, 1, 1-11, 2013.03, A partitioned approach by the coupling finite difference method (FDM) and the finite element method
(FEM) is developed for simulating the interaction between free surface flow and a thin elastic plate. The FDM, in
which the constraint interpolation profile method is applied, is used for solving the flow field in a regular fixed
Cartesian grid, and the tangent of the hyperbola for interface capturing with the slope weighting scheme is used for
capturing free surface. The FEM is used for solving structural deformation of the thin plate. A conservative
momentum-exchange method, based on the immersed boundary method, is adopted to couple the FDM and the
FEM. Background grid resolution of the thin plate in a regular fixed Cartesian grid is important to the computational
accuracy by using this method. A virtual structure method is proposed to improve the background grid resolution
of the thin plate. Both of the flow solver and the structural solver are carefully tested and extensive validations
of the coupled FDM–FEM method are carried out on a benchmark experiment, a rolling tank sloshing with a thin
elastic plate..
69. Changhong Hu, Makoto Sueyoshi, Fei Jiang, Kiminori Shitashima,Tetsuo Yanagi, Rise and Dissolution Modeling of CO2 Droplet in the Ocean, Journal of Novel Carbon Resource Sciences, 7, 12-17, 2013.02, A numerical approach is proposed to study the behavior of a natural carbon dioxide (CO2) droplet leaked from the
seafloor. Motion and deformation of the droplet at the initial stage are simulated by a lattice Boltzmann multi-phase
method to obtain the terminal velocity. The whole process of droplet rise and dissolution is modeled by a simplified
analytical method. The in-situ experiment case on a natural CO2 droplet at the Okinawa Trough (Shitashima, et al.1))
is studied by using the proposed numerical model. Numerical experiments show strong dependency between the
terminal velocity and the droplet density. The phenomena obtained in the on-sea observation are discussed by the
present numerical study..
70. Naruhiko Tan, Takayuki Aoki, Changhong Hu, Makoto Sueyoshi, Large-Scale Simulation of Violent Flow Impacting on an Obstacle, Proc. 2nd International Conference on Violent Flows, 253-260, 2012.09.
71. Changhong Hu, Chen Liu, Masashi Kashiwagi, Parallel Simulation of RIAM-CMEN for Strongly Nonlinear Wave-Ship Interaction, Proc. 2nd International Conference on Violent Flows, 112-117, 2012.09.
72. Changhong Hu, Kangping Liao, Wenyang Duan, Simulation of 2-D Deformable Cylinder Using Coupled FDM/FEM Method, Proceedings of the ASME 2012 31th International Conference on Ocean, Offshore and Arctic Engineering, CD-ROM, Paper No.: OMAE2012-83641, 2012.07.
73. Fei Jiang, Changhong Hu, Development of a Hybrid LBM/FVM Approach for Numerical Simulation of CO2, 日本船舶海洋工学会講演論文集, 14, 371-372, 2012.05.
74. Chen Liu, Changhong Hu, Parallel Implementation of CIP-based Method for Wave-Ship Interaction Simulation, 日本船舶海洋工学会講演論文集, 14, 273-274, 2012.05.
75. Kangping Liao, Changhong Hu, 2-D Numerical Simulation of Elastic Floating Structure Response to Regular Waves, 日本船舶海洋工学会講演論文集, 14, 197-198, 2012.05.
76. Xizeng Zhao, Changhong Hu, Numerical and experimental study on a 2-D floating body under extreme wave conditions, Applied Ocean Research, 10.1016/j.apor.2012.01.001, 35, 1-13, 2012.03, This paper presents further developments of a constrained interpolation profile (CIP)-based Cartesian grid method (Hu et al. [29]) to model nonlinear interactions between extreme waves and a floating body, which is validated against to a newly performed experiment. In the experiment, three kinds of waves (regular wave, focused wave and combined regular and focused wave) are generated and a box-shaped floating body with a superstructure is used. Validation computations on the experiment are performed by the improved CIP-based Cartesian grid method, in which the THINC/WLIC scheme (THINC: tangent of hyperbola for interface capturing; WLIC: Weighed line interface calculation), is used for interface capturing. The highly nonlinear wave-body interactions, including large amplitude body motions and water-on-deck are numerically investigated through implementation of focused wave input to the CIP-based method. Computations are compared with experimental results and good agreement is achieved. The effects of the water-on-deck phenomena and different input focus positions on the body response are also dealt with in the research..
77. Fei JIANG, Changhong Hu, Application of Lattice Boltzmann Method for Simulation of Turbulent Diffusion from a CO2 Lake in Deep Ocean, Journal of Novel Carbon Resource Sciences, 5, 10-18, 2012.02.
78. Changhong Hu, Kangping Liao, 2-D Numerical Simulation of Impact of Elastic Body on Free Surface, 第25回数値流体力学シンポジウム講演予稿集, Paper No. A10-3, 2011.12.
79. Fei JIANG, Changhong Hu, CO2 Diffusion Prediction by Lattice Boltzmann Method for Environment Assessment of Ocean CCS, Proc. the 5th International Symposium on the East Asian Environmental Problems(EAEP2011), 73-78, 2011.11.
80. Changhong Hu, Kangping Liao, Numerical Simulation of 2-D Water Entry with Rigid and Elastic Circular Cylinder, Proc. 7th International Workshop on Ship Hydrodynamics, 229-233, 2011.09.
81. Changhong Hu, Kangping Liao, FDM-FEM Coupled Method for Simulation of Interaction between Free Surface and Elastic Structure, Proc. 26th International Workshop on Water Waves and Floating Bodies, 61-64, 2011.04.
82. Changhong Hu, Masashi Kashiwagi, CIP Based Cartesian Grid Method for Prediction of Nonlinear Ship Motions, Proc. the Gothenburg Workshop on Numerical Ship Hydrodynamics, 553-556, 2010.12.
83. Xizeng Zhao, Changhong Hu, Experimental and Numerical Study on Interaction between Freak Waves and a Floating Body, 日本船舶海洋工学会講演論文集, 553-556, 2010.11.
84. Changhong Hu, Makoto Sueyoshi, Ryuji Miyake, Tingyao Zhu, Development of CIP based Numerical Method for Prediction of Nonlinear Wave Loads on Real Ships, Proc. of the William Froude Conference: Advances in Theoretical and Applied Hydrodynamics - Past and Future, 73-80, 2010.11.
85. Changhong Hu, Kyung-Kyu Yang, Yonghwan Kim, 3-D Numerical Simulations of Violent Sloshing by CIP-based Method, Proc. the 9th International Conference on Hydrodynamics, 253-258, 2010.10.
86. Fei Jiang, Changhong Hu, Development of Environmental Flow Simulation Code for GPU Computing, Proc. the 4th International Symposium on the East Asian Enviromental Problems, 201-206, 2010.09.
87. Kangping Liao, Changhong Hu, Wenyang Duan, Liang Zhang, Numerical Simulation of Vertical Axis Wind Turbine with Discrete Vortex Method, Proc. the 4th International Symposium on the East Asian Enviromental Problems, 185-190, 2010.09.
88. Kyungkyu Yang, Yonghwan Kim, Changhong Hu, Numerical Simulation of 2D Violent Sloshing Flows by Using CCUP Method, International Journal of Offshore and Polar Engineering, 20, 3, 204-209, 2010.09.
89. Xizeng Zhao, Changhong Hu, Zhaochen Sun, Numerical simulation of extreme wave generation using VoF method, Journal of Hydrodynamics, 22, 4, 466-477, 2010.08.
90. Kangping Liao, Changhong Hu, Wenyang Duan, Free surface impact analysis with structure deformation, The 5th Asia-Pacific Workshop on Marine Hydrodynamics, 211-215, 2010.07.
91. Xizeng zhao, Hu Changhong, Sun Zhaochen, Numerical simulation of focused wave generation using CIP method, Proceedings of the Twentieth International Offshore and Polar Engineering Conference, 596-603, 2010.06.
92. Changhong Hu, Makoto Sueyoshi , Ryuji Miyake, Tingyao Zhu, Computation of Fully Nonlinear Wave Loads on a Large Container Ship by CIP based Cartesian Grid Method, Proceedings of the ASME 2010 29th International Conference on Ocean, Offshore and Arctic Engineering, OMAE2010-20286, 2010.06.
93. Changhong HU, Makoto SUEYOSHI, Numerical simulation and Experiment on Dam Break Problem, Journal of Marine Science and Application, 9, 2, 109-114, 2010.06.
94. Masashi Kashiwagi, Changhong Hu, 3D Effects on Measured Results Using a 2D Model in a Narrow Wave Channel, International Journal of Offshore and Polar Engineering, 20, 2, 88-94, 2010.06.
95. Changhong Hu, Makoto Sueyoshi,Masashi Kashiwagi, Numerical Simulation of Strongly Nonlinear Wave-Ship Interaction by CIP/Cartesian Grid Method, Int. Journal of Offshore and Polar Engineering, 20, 2, 81-87, 2010.06.
96. Xizeng Zhao, Changhong Hu, Zhaochen Sun, Validation of the initialization of a numerical wave flume using a time ramp, Fluid Dynamics Research, 42, 045504, 2010.06.
97. Changhong Hu, 3-D Numerical Wave Tank by CIP-based Cartesian Grid Method, Proc. 25th International Workshop on Water Waves and Floating Bodies, 61-64, 2010.05.
98. Guanghua He, Masashi Kashiwagi, Changhong hu, Nonlinear Solution for Vibration of Vertical Elastic Plate by Initial Elevation of Free Surface, Int. Journal of Offshore and Polar Engineering, 22, 1, 34-40, 2010.03.
99. Xizeng Zhao,Changhong Hu, Zhaochen Sun, Numerical Generation of Freak Wave in a 2D-NWT, 日本船舶海洋工学会講演論文集, 2009.11.
100. Numerical Simulation of Ship Motion in Oblique Waves by CIP based Cartesian Grid Method.
101. Numerical Simulation of Water Wave by THINC Scheme.
102. Changhong Hu, Makoto Sueyoshi , Ryuji Miyake, Tingyao Zhu , Hirotsugu Dobashi, A Validation Study of Applying the CIP Method and the MPS Method to 2-D Tank Sloshing, Proceedings of the 19th International Offshore and Polar Engineering Conference, 198-204, 2009.06.
103. Changhong Hu, Masashi Kashiwagi, Two-dimensional numerical simulation and experiment on strongly nonlinear wave–body interactions , Journal of Marine Science and Technology, 10.1007/s00773-008-0031-4, 14, 2, 200-213, 2009.06.
104. Changhong Hu, Makoto Sueyoshi, Ryuji Miyake, Tingyao Zhu, CFD Prediction of Added Resistance in Regular Incident Waves by A CIP-Based Cartesian Grid Method, Proceedings of 3rd PAAMES and AMEC2008, pp.209~214, 2008.10.
105. Changhong Hu, Masashi Kashiwagi, and Makoto Sueyoshi, Improvement towards High-Resolution Computation on Strongly Nonlinear Wave-Induced Motions of an Actual Ship, Proc. of 27th Symposium on Naval Hydrodynamics, pp. 525-534, 2008.10.
106. Changhong Hu, Masashi Kashiwagi, Makoto Sueyoshi and Izumi Nakagiri, Numerical Simulation of Strongly Nonlinear Wave-Ship Interaction by CIP/Cartesian Grid Method, Proc. 18th International Offshore and Polar Engineering Conference , pp. 143-147, 2008.07.
107. Masashi Kashiwagi, Changhong Hu, Takuya Hashimoto and Makoto Yasunaga, Consideration on 3-D Effects on Results of Forced Oscillation Test in a 2-D Wave Channel, Proc. 18th International Offshore and Polar Engineering Conference, pp. 39-46, 2008.07.
108. Changhong Hu, Masashi Kashiwagi, A Conservative CIP Method for Violent Free Surface Flows, Proc. 23rd International Workshop on Water Waves and Floating Bodies, pp.81-84, 2008.04.
109. Masashi Kashiwagi, Changhong Hu, Makoto Sueyoshi, CFD Computation of Strongly Nonlinear Wave-Body Interactions on the Free Surface, Proc. the 6th Osaka Colloquium on Seakeeping Performance and Stability of Ships, pp. 83-92, 2008.02.
110. Changhong Hu, Masashi Kashiwagi, Ning Ma, 2-D Numerical Simulation of Water Entry Using CIP Based Method, Proc. of APCOM'07-EPMESC XI, paper no. MS7-1-1 (CD-ROM), 2007.12.
111. Changhong Hu, Masashi Kashiwagi, Feng Xiao, 3D Numerical Simulation of Violent Sloshing by Conservative CIP Method, Proceedings of Internation Conference on Violent Flow, pp. 373-377, 2007.11.
112. Xingying Zhu, Odd Faltinsen, Changhong Hu, Water Entry and Exit of a Horizontal Circular Cylinder, Journal of Offshore Mechanics and Arctic Engineering, 10.1115/1.2199558, 129, 4, 253-264, 2007.11.
113. Masashi Kashiwagi, Changhong Hu, Ryuji Miyake, Tingyao Zhu, A CIP-Based Cartesian Grid Method for Nonlinear Wave-Body Interactions, Proceedings of the 10th International Symposium on Practical Design of Ships and Other Floating Structures, Vol.2, pp.894-902, 2007.09.
114. Changhong Hu and Masashi Kashiwagi, Numerical and Experimental Studies on Three-Dimensional Water on Deck with a Modified Wigley Model, Proc. 9th Int. Conf. on Numerical Ship Hydrodynamics, Vol 1, pp.159-169, 2007.08.
115. Yoshiki Nishi, Changhong Hu, Masashi Kashiwagi, Multigrid Technique for Numerical Simulations of Water Impact Phenomena
, Int. J. of Offshore and Polar Engineering, 16, 4, 283-289, 2006.12.
116. Changhong Hu and Masashi Kashiwagi, Wave-Body Interaction Experiments for Validation of CFD method on Strongly Nonlinear Problems, Proc. 9th Numerical Towing Tank Symposium , pp. 59-64, 2006.10.
117. Changhong Hu and Masashi Kashiwagi, Validation of CIP-based Method for Strongly Nonlinear Wave-Body Interactions, Proc. of 26th Symposium on Naval Hydrodynamics, pp 247-258, 2006.09.
118. Hu, CH, Kashiwagi, M, Kishev, Z, Sueyoshi, M and Faltinsen, O., Application of CIP Method for Strongly Nonlinear Marine Hydrodynamics, Ship Technology Research, V.53, No. 2, pp 74-87, 2006.06.
119. Changhong Hu, Masashi Kashiwagi and Akihiko Kitadai, Numerical Simulation of Strongly Nonlinear Wave-Body Interactions with Experimental Validation, Proceedings of the 16th International Offshore and Polar Engineering Conference, Vol. 4, pp.420-427, 2006.06.
120. Changhong Hu, Masashi Kashiwagi and Akihiko Kitadai, CFD Simulation and Laboratory Experiment on 2-D Strongly Nonlinear Wave-Body Interactions, Proc. 3rd Asia-Pacific Workshop on Marine Hydrodynamics, pp.232-236, 2006.06.
121. Zdravko Kishev, Changhong Hu and Masashi Kashiwagi, Numerical simulation of violent sloshing by a CIP-based method, Journal of Marine Science and Technology, V. 11, pp.111-122, 2006.06.
122. Changhong Hu and Masashi Kashiwagi, Experimental Validation of the Computation Method for Strongly Nonlinear Wave-Body Interactions, Proc. 21st International Workshop on Water Waves and Floating Bodies, pp.73-76, 2006.04.
123. 3D numerical simulation of strongly nonlinear ship-wave interactions by CIP method
Changhong Hu, Masashi Kashiwagi
Proc. 15th Computational Mechanics Conference.
124. 3D numerical simulation of strongly nonlinear ship-wave interactions by CIP method
Changhong Hu, Masashi Kashiwagi
Proc. 15th Computational Mechanics Conference.
125. Changhong Hu, Masashi Kashiwagi and Odd Faltinsen, 3-D Computation of Ship-Wave Interaction by CIP / Cartesian Grid Method, Proc. 8th Numerical Towing Tank Symposium, 2005.10.
126. Changhong Hu, Masashi Kashiwagi and Odd Faltinsen, Recent Progress in CIP Method for Strongly Nonlinear Ship-Wave Interactions, Proc. 4th International Workshop on Ship Hydrodynamics, pp.41-47, 2005.09.
127. Xinying Zhu, Odd Faltinsen and Changhong Hu, Water entry and exit of a horizontal circular cylinder, Proc. 24th International Conference on Offshore Mechanics and Arctic Engineering, OMAE2005-67311, 2005.06.
128. Changhong Hu, Odd Faltinsen and Masashi Kashiwagi, 3-D Numerical Simulation of Freely Moving Floating Body by CIP Method, Proc. 15th International Offshore and Polar Engineering Conference, 674-679, Vol. 4, pp.674-679, 2005.06.
129. Changhong Hu, Odd Faltinsen and Masashi Kashiwagi, 3-D Numerical Simulation of Water-Entry Problem by CIP based Cartesian Grid Method, Proc. 20th International Workshop on Water Waves and Floating Bodies, 2005.05.
130. Changhong Hu and Masashi Kashiwagi, A CIP-Based Method for Numerical Simulations of Violent Free Surface Flows, Journal of Marine Science and Technology, 10.1007/s00773-004-0180-z, 9, 4, 143-157, Vol.9, No.4, pp. 143-157, 2004.12.
131. Changhong Hu, Odd Faltinsen and Masashi Kashiwagi, Changhong Hu, Odd Faltinsen and Masashi Kashiwagi, Proc. 7th Numerical Towing Tank Symposium, 2004.10.
132. Changhong Hu, Masashi Kashiwagi and Zdravko Kishev, Numerical Simulation of Violent Sloshing by CIP Method, Proc. 19th International Workshop on Water Waves and Floating Bodies, pp.67-70, 2004.03.
133. Nobuyoshi Fukuchi and Changhong Hu, A Pseudofield Model Approach to Simulate Compartment-Fire Phenomena for Marine Fire Safety Design, Journal of Marine Science and Technology, 10.1007/s00773-003-0171-5, 8, 4, 177-184, Vol.8, No.4, pp. 177-184, 2004.03.
134. Changhong Hu and Nobuyoshi Fukuchi, A Field Modeling Approach to Prediction of Hot Gas Movement Induced by Marine Compartment Fires, International Journal of Offshore and Polar Engineering, 13, 4, 249-253, Vol. 13, No. 4, pp.249-253, 2003.12.
135. Changhong Hu and Masashi Kashiwagi, Development of CFD Simulation Method for Extreme Wave-Body Interactions, Proceedings of the 8th International Conference on Numerical Ship Hydrodynamics, Vol.2, pp. 50-57, 2003.09.
136. Changhong Hu and Masashi Kashiwagi, Numerical Simulation of Non-Linear Free Surface Wave Generation by CIP Method and Its Applications, Proceedings of the 13th International Offshore and Polar Engineering Conference, 294-299, Vol. 3, pp. 294-299, 2003.05.
137. Changhong Hu and Masashi Kashiwagi, A CIP Based Numerical Simulation Method for Extreme Wave-Body Interaction, Proc. 18th International Workshop on Water Waves and Floating Bodies, 2003.04.
138. Numerical Study on Interaction of Waves with Structures by CIP Method
Changhong Hu, Masashi Kashiwagi and Tsutomu Momoki
Proc. 15th Computational Mechanics Conference
pp. 433-434.
139. A Study on the Ventilation System of Metallic Fume and the Working Environment
in a Fabrication Shop (Part 1) The Analysis of Fume Transportation in Turbulent flow
Changhong Hu and Nobuyoshi Fukuchi
Journal of the Society of Naval Architects of Japan
Vol. 191, pp. 159-168.
140. A Study on Numerical Simulation of Turbulent Natural Convection by LES
Changhong Hu and Nobuyoshi Fukuchi
Transactions of the West-Japan Society of Naval Architects
Vol. 102, pp. 209-217.
141. The Characteristic Analysis of Turbulent Diffusion on the Functional Design of Marine Systems (Part 2) The Effect of Heat Radiation on Turbulent Natural Convection in an Enclosure
Changhong Hu, Nobuyoshi Fukuchi and Tohru Nakashima
Journal of the Society of Naval Architects of Japan
Vol 189, pp.127-135.
142. Three Dimensional Numerical Simulation of the Turbulent Thermal Convection in an Open Compartment
Changhong Hu, Nobuyoshi Fukuchi and Koichi Yoshida
Transactions of the West-Japan Society of Naval Architects
Vol. 100, pp. 189-198.
143. Computation of Turbulent Thermal Convection with Large Temperature Variation (Part 1) Numerical Simulation of Compressible Flow Using Low Mach-Number Approximation
Changhong Hu and Nobuyoshi Fukuchi
Journal of the Society of Naval Architects of Japan
Vol. 186, pp. 663-671.
144. The Threshold Conditions and Characteristic Analysis of the Marine Fire Spread Phenomena (Part 2) Heat Transfer in Multi-Compartments by Field Mathematical Model
Nobuyoshi Fukuchi, Changhong Hu, Hiromasa Ohishi and Hisahiro Fujii
Journal of the Society of Naval Architects of Japan
Vol 185, pp. 151-162.
145. A Numerical Analysis on Instability os Stratified Shear Flow
Changhong Hu and Nobuyoshi Fukuchi
Journal of the Society of Naval Architects of Japan
Vol 183, pp. 19-26.