Kyushu University Academic Staff Educational and Research Activities Database
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CHANGHONG HU Last modified date:2023.06.09



Graduate School
Other Organization


Homepage
https://kyushu-u.pure.elsevier.com/en/persons/changhong-hu
 Reseacher Profiling Tool Kyushu University Pure
http://www.riam.kyushu-u.ac.jp/ship/STAFF/hu/index.html
Academic Degree
PhD in Engneering
Country of degree conferring institution (Overseas)
Yes Bachelor Master Doctor
Field of Specialization
Marine renewable energy, Ship and ocean engineering, Computational fluid dynamics
ORCID(Open Researcher and Contributor ID)
0000-0002-8308-9180
Total Priod of education and research career in the foreign country
01years00months
Outline Activities
- Research activities -
Theoretical analysis, physical experiments, and numerical simulations are carried out to study the wave safety problems of ships and offshore structures, and hydrodynamic problems related to the development of marine renewable energy utilization. The following is a chronological list of the major research themes conducted (or being conducted) up to the present.

1. Investigation of slow drift damping due to viscous force acting on a cylinder.
2. Environmental assessment of Mega Float.
3. Development of multiphase flow CFD method and its application to fire simulation and gas diffusion prediction.
4. Experiments and numerical calculations on fire protection and fire extinguishing in ship engine rooms.
5. Development of a CIP-based method for strongly nonlinear wave-body interactions.
6. Development of a coupled fluid-structure analysis method and its application to wave safety and system optimization of FOWT.
7. Development of a new floating platform for multiple wind turbines.
8. Tidal current turbine wake modeling and array arrangement optimization.
9. Development of next-generation CFD solver for strongly nonlinear wave-body interactions.
10. Development of Floating Offshore Tower for Power Transmission System Over the Sea.
11. Development of TLP type floating offshore wind measurement tower

- Education activities -
From 1995 to 2002, as an assistant professor of Kyushu University, involved in education activities.
From 2002, as an associate professor, and from 2014 as a professor of Kyushu University, in charge of a cooperative laboratory in the Department of Earth System Science and Technology, Interdisciplinary Graduate School of Engineering Sciences.
Research
Research Interests
  • Study of skirt suction jacket (SSJ) foundation for bottom-mounted offshore wind turbines
    keyword : Bottom-mounted offshore wind turbine, SSJ foundation, Towing stability
    2022.04.
  • Development of a medium-sized wind lens turbine and its multi-rotor implementation
    keyword : WLT, Multi-rotor system, CFD simulation, Wind tunnel experiment
    2022.04.
  • Development of TLP-Type Floating Mast/Lidar System for Overhead Wind Measurement
    keyword : Floating Offshore Tower, Hybrid Mast/Lidar System, TLP
    2020.04.
  • Development of TLP-Type Floating Offshore Tower for Overhead Power Transmission in the Sea
    keyword : Floating Offshore Tower, Overhead Power Transmission System in the Sea, TLP
    2016.04.
  • Development of floating offshore wind turbine system with fishery cooperation for distributed power supply
    keyword : Offshore wind energy, new-type floating platform, distributed power supply, fishery cooperation
    2012.04.
  • Tidal current turbine wake modelling and array arrangement optimization for tidal farm
    keyword : Tidal current energy, wake modelling, arrangement optimization
    2014.07.
  • Development of next-generation high-performance CFD solver and application to fluid-structure interaction analysis
    keyword : CFD, Fluid-Structure Interaction, Free surface impact
    2008.04.
  • Study on wave safety and wake prediction of large floating offshore wind turbines
    keyword : Large-scale floating offshore wind turbine, Safety analysis, Wave impact, CFD
    2010.04.
  • Development of efficient CFD method for strongly nonlinear wave body interactions
    keyword : strongly nonlinear free surface surface motion, computational fluid dynamics, interface capturing method, wave impact
    2002.04Development of CFD simulation method for extremely nonlinear wave-body interaction Numerical simulation of floating body motion in rough seas is a challenging subject. The main difficulty arises from that the topology of free surface may be largely distorted or broken up, which makes it impossible to apply the conventional numerical method such as the potential-flow based method by BEM. In this study a new numerical method is developed. This method is a CIP based finite difference method which is not only able to handle the complex phenomena associated with the wave-body interaction, but also have relatively simple scheme in order to perform a three-dimensional time-dependent numerical simulations in an acceptable spatial and temporal resolution at a reasonable cost..
  • Environmental assessment on marine CCS
    keyword : Marine CCS, deep ocean storage, diffusion simulation, environmental assessment
    2010.04~2016.03.
  • Development of a New Ship Hull Form for Reducing CO2 Emission in a Seaway
    keyword : CO2 emission reduction, Energy-saving ship hull, CFD simulation
    2009.04.
  • Numerical simulation of marine engine room fires
    keyword : engine room fire, CFD simulation, fire modeling
    2000.04~2004.03In this research, a CFD model has been developed for numerical simulation of marine fires..
  • Numerical simulation of low-concentration particle-gas multi-phase flows
    keyword : metallic fume, numerical simulation, low-concentration particle-gas multi-phase flow, working environment
    1998.04~2002.03An high-efficiency ventilation System is very important for improving working environment in a fabrication shop of shipyard. The metallic fume generated from the welding or cutting process is expected to predict. In this research a numerical simulation method is developed and improved for this purpose. Now research on applying this method to prediction general air polution problems is ongoing..
Current and Past Project
  • In November 2022, a Ministry of the Environment-funded project on the Technological development of a medium-sized 200kW wind lens turbine and its multi-rotor system was adopted, and Kyushu University will conduct hydrodynamic studies (optimized lens design, the hydrodynamic study of the multi-rotor system, etc.) on wind turbine development as a joint implementer.
  • For developing a skirt suction jacket (SSJ) installation method that does not require large operation vessels, model experiments and numerical simulations are carried out to investigate methods for towing and sinking the SSJ.
  • Understanding VIV behavior in the tidal flow of power transmission cables for bottom-mounted wind turbines is crucial for the structural and fatigue design of the cables. This study aims to clarify the relationship between VIV behavior and internal stresses of the cables through tank experiments and numerical analysis and to develop efficient numerical prediction tools.
  • The final goal of this research is to develop an novel power transmission system over the sea, of which the total cost will be much lower than the conventional system. In this research project, an low cost installing method for the floating tower will be studied by both experiment and numerical simulation.
  • The final goal of this research is to establish an effective CFD analytical procedure for numerical simulation of a tidal current farm. A CFD method based on OpenFOAM will be developed for predicting the force coefficients and characterizing the wake of a tidal turbine. The experiment will also be carried out for validation of the CFD code.
  • As a part of large scale floating ocean renewable energy system project of RIAM, Kyushu University, a noval multi-purpose, cost effective semi-submersible type platform is developed with the coorperation of industries.
  • Fundemental researches are carried out on safety and environment assessment of ocean CCS, which is a project promoted by the "International Institute for Carbon-Neutral Energy Research (I2CNER)" of Kyushu University.
Academic Activities
Books
1. Masashi Kashiwagi, Changhong Hu and Makoto Sueyoshi, Numerical Computation Methods for Extremely Nonlinear Wave-Body Interactions,
Chapter 12 : Numerical Computation Methods for Extremely Nonlinear Wave-Body Interactions
, The world Scientific Publishing Co., in the series of Advances in Coastal and Ocean Engineering, Vol. 11, 2009.05.
Reports
1. CIP Method.
Papers
1. Yiding Hu, Cheng Liu, Min Zhao, Changhong Hu, High-fidelity simulation of an aerated cavity around a surface-piercing rectangular plate, Physics Review Fluids, 10.1103/PhysRevFluids.8.044003, 8, No.044003, 2023.04.
2. Liu, Cheng; Gao, Ruoqing; Hu, Changhong, A consistent mass-momentum flux computation method for the simulation of plunging jet, Physics of Fluids, 10.1063/5.0084894, 34, 3, 2022.03.
3. Zhu, Hongzhong; Hu, Changhong, A study on floating overhead power transmission system for offshore energy development: Design and modeling approach, Ocean Engineering, 10.1016/j.oceaneng.2021.109528, 236, 2021.09.
4. Al-Salami, Jabir; Kamra, Mohamed M.; Hu, Changhong, A high order flux reconstruction interface capturing method with a phase field preconditioning procedure, Journal of Computational Physics, 10.1016/j.jcp.2021.110376, 438, 2021.08, This paper presents a simple and highly accurate method for capturing sharp interfaces moving in divergence-free
velocity fields using the high-order Flux Reconstruction approach on unstructured grids. A well-known limitation of
high-order methods is their susceptibility to the Gibbs phenomenon; the appearance of spurious oscillations in the
vicinity of discontinuities and steep gradients makes it difficult to accurately resolve shocks or sharp interfaces. In
order to address this issue in the context of sharp interface capturing, a novel, preconditioned and localized phasefield
method is developed in this work. The numerical accuracy of interface normal vectors is improved by utilizing
a preconditioning procedure based on the level set method with localized artificial viscosity stabilization. The developed
method was implemented in the framework of the multi-platform Flux Reconstruction open-source code PyFR
[1]. Kinematic numerical tests in 2D and 3D conducted on different mesh types showed that the preconditioning
procedure significantly improves accuracy with little added computational effort. The results demonstrate the conservativeness
of the proposed method and its ability to capture highly distorted interfaces with superior accuracy
when compared to conventional and high-order VOF and level set methods. Dynamic interface capturing validation
tests were also carried out by coupling the proposed method to the entropically damped artificial compressibility
variant of the incompressible Navier-Stokes equations. The high accuracy and locality of the proposed method offer
a promising route to carrying out massively-parallel, high accuracy simulations of multi-phase, incompressible phenomena..
5. Jabir Al Salami, Changhong Hu, Mohamed M. Kamra, Kazuaki Hanada, Magnetic Induction and Electric Potential Smoothed Particle Magnetohydrodynamics for Incompressible Flows, International Journal for Numerical Methods in Fluids, 10.1002/fld.4906, 93, 3, 720-747, 2020.08, In order to solve incompressible, nonideal magnetohydrodynamic (MHD) free-surface flows, two weakly compressible smoothed particle hydrodynamics models, with and without the consideration of magnetic induction, are developed. The SPH formulation for magnetic induction magnetohydrodynamics (SPMHD), which is popular in astrophysical studies, is applied for the first time to incompressible free-surface MHD flows, such as liquid metal flows, with the consideration of nonideal MHD effects and boundaries with arbitrary electric conductivity. An SPMHD implementation using the inductionless approximation is also proposed for both electrically conductive and insulating boundaries, in which a Poisson equation is solved to compute the Lorentz force instead of evolving the magnetic induction equation. Both proposed methods are validated against MHD benchmarks, including free-surface MHD cases. The proposed inductionless SPMHD implementation has the advantages of stability and relaxed time-step restrictions, but is only accurate at a low range of Hartmann numbers. For high Hartmann number problems, magnetic induction SPMHD model is more accurate. The computational efficiency and conservation error of the two models are compared and discussed..
6. 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..
7. Cheng Liu, Changhong Hu, An adaptive high order WENO solver for conservation laws, Communications in Computational Physics, 10.4208/cicp.OA-2018-0059, 26, 3, 719-748, 2019.09, This paper presents an implementation of the adaptive hybrid WENO (weighted essentially non-oscillatory) scheme based on our previous investigations for compressible multi-medium flows (Liu and Hu, J. Comput. Phys., 342 (2017), 43-65). In this study a simple and efficient method is developed for Euler equations and Navier-Stokes equations arising from the conservation laws. A class of high order weighted essentially non-oscillatory (WENO) schemes are applied to resolve the complicated flow structures and shock waves. Classical WENO schemes are computationally expensive in calculating the non-linear weight and smoothness indicators. We propose a block-structured adaptive mesh method together with a modified hybrid-WENO scheme to reduce the cost, the reconstruction is only performed at non-smooth region. Comparisons of WENO scheme with various smoothness indicators and different Lax-Friedrich flux vector splitting methods are performed on block structured adaptive mesh. Benchmark tests show present adaptive hybrid WENO method is low-dissipative and highly robust. The 2-D/3-D shock wave boundary layer interaction are simulated to verify the efficiency of present AMR (adaptive mesh refinement) solver in predicting turbulent flow..
8. 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..
9. 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..
10. 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..
11. 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..
12. 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..
13. 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..
14. 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..
15. 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.
16. 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..
17. 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.
18. 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..
19. 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..
20. 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..
21. 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..
22. 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.
23. 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.
24. 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.
25. 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.
26. 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.
27. 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.
28. 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.
29. 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.
30. 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.
31. 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.
32. 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.
33. 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.
34. 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.
35. 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.
36. 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.
Presentations
1. Changhong Hu, Mohamed M. Kamra, Seiya Watanabe, Numerical and Experimental Investigation of Dam-Break Flow Against a Vertical Cylinder, 36th International Workshop on Water Waves and Floating Bodies, 2018.04.
2. Changhong Hu, Experimental and Numerical Study of Dam Break Flow Impact on a Vertical Cylinder, The 4th Symposium on Computational Marine Hydrodynamics, 2021.01.
3. Changhong Hu, Numerical and Experimental Study on Sloshing in a Tank with Complicated Inner Structures, The 2nd International Workshop on Numerical and Experimental Modelling of Wave -Structure Interaction, 2020.11.
4. Changhong Hu, Development of a Medium-Scale Floating Offshore Wind Turbine System, International Workshop on Offshore Wind Energy (IWOWE), 2019.12.
5. Changhong Hu, Makoto Sueyoshi, Chen, Liu, Yusaku Kyozuka, Yuji Ohya, Numerical and Experimental Study on a Floating Platform for Offshore Renewable Energy, the ASME 2012 32th International Conference on Ocean, Offshore and Arctic Engineering , 2013.06.
6. Development of CIP Based Cartesian Grid Method and Its Application to Strongly Nonlinear Wave-Body Interactions.
Membership in Academic Society
  • The International Society of Offshore and Polar Engineers
  • The Japan Society of Naval Architects and Ocean Engineers
  • The Japan Society of Mechanical Engineers
Educational
Educational Activities
From 1995 to 2002, as an assistant professor at Kyushu University, involved in educational activities.
From 2002, as an associate professor, and from 2014 as a professor of Kyushu University, in charge of a cooperative laboratory in the Department of Earth System Science and Technology, Interdisciplinary Graduate School of Engineering Sciences. Lectures for graduated students are as follows.

Master Course:
(1) Earth system fluid dynamics 1 (shear, 2 credits)
(2) An Introduction to CFD (2 credits)
(3) Dynamics of ocean systems Seminar (4 credits)
(4) Practical data processing (common, shear, 2 credits)

Doctor Course:
(1) Special lecture on ocean systems dynamics (4 credits)
(2) Tutorials on PhD thesis (2 credits)
(3) Tutorials on interdisciplinary engineering sciences (Environment) (shear, 2 credits)
Social
Professional and Outreach Activities
Academic and industry collaboration

2003-2007 Development of CFD for strongly nonlinear wave-body interactions, (with Akishima Laboratories INC.)
2008-2013 CFD development for predicting ship hydrodynamics with the consideration of hull form above waterline, (with Mitrui Engineering and Shipbuilding Co., LtD)
2009-2010 CFD development for Prediction of wave loads in bow seas, (with ClassNK)
2011-2013 Study on safety assessment method for floating wind turbine, (with ClassNK)
2012-2015 Development of novel ocean platform for offshore wind, (with Oshima Shipbuilding, Shikurushima Dock, Tsuneishi holdings)
2015-present Development of TLP floating tower for offshore power transmission in the air, (with Furukawa Electric, Toray, Akishima Laboratory, Japan Radio)

International collaboration research
2009-2010 Numerical simulation on violent tank sloshing, (with Seoul National University, Korea)
2012-2014 Experimental and numerical study on tidal energy converters, (with Harbin Engineering University, China)
2015-present Delopment of high performance CFD method for FOWT, (with Shanghai Jiao Tong University, China).