インデューサに生じるキャビテーション脈動の発生機構解明と事前検知・回避法の確立
キーワード：ポンプインデューサ，キャビテーション脈動，事前検知，
1998.04.

翼・翼列の非定常キャビテーション流れに関する基礎研究
キーワード：キャビテーション，非定常流れ
1998.04.

キャビテーションの熱力学的効果に関する研究
キーワード：キャビテーション，熱力学的効果
2005.04.

簡易構造を有するダクト付きダリウス形低落差水力タービンに関する研究
キーワード：ダリウス水車，マイクロ水力，低コスト
1998.04.

気液二相流適用形遠心ポンプの研究開発とそのマイクロバブル生成への応用
キーワード：遠心ポンプ，気液二相流，マイクロバブル
1998.04.

二重反転式軸流ポンプの高性能設計に関する研究
キーワード：ターボ機械，軸流ポンプ，二重反転形，高性能化
1999.04.

カーボンニュートラルに貢献する熱流体技術の開発に向けた産学ネットワーキングのための研究分科会（RC297）
2023.04～2025.03, 代表者：村井 祐一, 北海道大学, 日本機械学会.

水素利用等先導研究開発事業／エネルギーキャリアシステム調査・研究／水素キャリアシステムの高性能化と課題解決のための基盤流体技術の構築
2022.08～2023.03, 代表者：宮川和芳, 早稲田大学.

流れの先進的計測・シミュレーション法と流体情報の高度利用に関する研究分科会（RC286）
2020.04～2023.03, 代表者：杉山 和靖, 大阪大学, 日本機械学会.

流れの数値解析と実験計測の双方向連携に関する研究分科会（RC277）
2018.04～2020.03, 代表者：村井 祐一, 北海道大学, 日本機械学会.

流れの知的制御とそれを実現するための先進計測法に関する研究分科会（RC270）
2016.04～2018.03, 代表者：亀田 正治, 東京農工大, 日本機械学会.

複雑流動現象の解析技術とその実用化に関する研究分科会（RC263）
2014.04～2016.03, 代表者：川野 聡恭, 大阪大学, 日本機械学会.

流体性能の高精度予測と革新的流体設計分科会
2020.04～2024.03, 代表者：加藤千幸, 東京大学, ターボ機械協会.

「富岳」を利用した革新的流体性能予測技術の開発
2020.04～2023.03, 代表者：加藤千幸, 東京大学.

ターボ機械HPC実用化分科会
2016.10～2020.03, 代表者：加藤千幸, 東京大学, ターボ機械協会.

ターボ機械HPC総括分科会
2014.10～2016.10, 代表者：加藤千幸, 東京大学, ターボ機械協会.

主要著書

主要原著論文

1.	Yohei Tanaka, Takahiro Kitabata, Koichi Nasu, Satoshi Watanabe, Akira Sakata, Suppression of Cavitation Surge in Turbopump With Inducer by Reduced-Diameter Suction Pipe With Swirl Brake, Journal of Fluids Engineering, Transactions of the ASME, 10.1115/1.4052926, 144, 7, 2022.07, Downsizing and high power density of turbopumps is achieved by increasing their rotational speed. Cavitation often becomes a problem while the influence of cavitation will be generally relieved by employing an inducer before the impeller. For general-use turbopumps with an inducer, instability-free operation, as well as high suction performance is required in a wide flow rate range including extremely low flow rate. However, the cavitation surge phenomenon with low frequency and large amplitude is often to be a serious problem even with inducer when operated at very low flow rates. In this study, a reduced-diameter suction pipe (RSP) equipped with swirl brake (SB) was proposed for a suppression device of the inlet backflow as well as of the cavitation surge through removing the swirling velocity component. The effectiveness of this device was investigated by computational fluid dynamics (CFD) and experiments. First, several geometries of RSP with SB were examined by CFD, and it was found that the extension of inlet backflow was stopped at this device provided that the swirl brake had a sufficient radial or axial length. Then, one of the proposed RSP with SB was manufactured, and the experimental evaluation of the effectiveness of this device was conducted. It seemed that RSP with SB could well prevent the extension of inlet backflow. The cavitation surge was completely suppressed even at extremely low flow rates. As a result, the suction performance was also improved at low flow rates..
2.	Keisuke Kobayashi, Yusuke Katayama, Satoshi Watanabe, Shin Ichi Tsuda, Experimental Investigation on Cavity Pressure Inside Sheet Cavitation, Journal of Fluids Engineering, Transactions of the ASME, 10.1115/1.4051580, 143, 12, 2021.12, The gas content is one of the important factors in cavitation, which may increase the pressure inside the cavity through the diffusive mass transfer of the dissolved gas into the cavity. In the present study, we try to directly measure the cavity pressure inside the sheet cavity at the throat of a converging-diverging nozzle. Then the influences of the flow velocity and the gas content (amount of dissolved oxygen) on the gas partial pressure are investigated. It is found that, even in low gas content level, the cavity pressure is slightly but apparently higher than the saturated vapor pressure, indicating the presence of gas partial pressure. It is observed that the gas partial pressure in significantly developed cavitation is almost constant regardless of the flow velocity but slightly increases against the increase of the saturation level of dissolved gas. It is also found that the gas partial pressure inside cavity depends on the degree of cavitation development; the gas partial pressure decreases with the development of cavitation..
3.	Satoshi Watanabe, Yoshinobu Tsujimoto, Prediction of cavitation surge onset point by one-dimensional stability analysis, International Journal of Fluid Machinery and Systems, 10.5293/IJFMS.2021.14.2.199, 14, 2, 199-207, 2021.06, Cavitation instabilities such as rotating cavitation and cavitation surge often occur in high speed turbopumps. It has been shown by a stability analysis that the cause of cavitation instabilities is explained by the positive mass flow gain factor, representing the increase of cavity volume against the decrease (increase) of flow rate (incidence angle). The cavitation compliance, representing the increase of cavity volume in response to the decrease of inlet pressure, determines the frequency of instabilities. However, one-dimensional stability analysis cannot be directly used for the prediction of the onset point of cavitation surge when quasi-steady assumption is applied. In the present study, unsteady characteristics, i.e. the phase lag in the response of cavity volume against the flow rate/inlet pressure fluctuations, are taken into account in a stability analysis of cavitation surge in the form of lag element. The onset criterion considering the time lag is newly proposed for one-dimensional stability analysis, and the criterion is validated by comparisons with a two-dimensional stability analysis based on a singularity method applied to a free streamline theory..
4.	T. Takamine, S. Nakano, S. Watanabe, H. Watanabe, Effect of axial offset of rotor on thrust characteristics of a centrifugal pump, Journal of Physics: Conference Series, 10.1088/1742-6596/1909/1/012073, 1909, 1, 2021.05, To ensure the reliability of multi-stage centrifugal pumps, the prediction of axial thrust is an important issue for the design of balancing device and selection of thrust bearing. However, it is known that the fluid forces acting on rotor could be sensitively affected by the geometrical relations between rotor and stator especially at the low flow rate. Among them, the effect of axial offset of rotor has not been studied sufficiently though the axial offset is easily caused by accumulation of manufacturing tolerances and assembling errors. In this study, experimental/numerical investigations on the effect of axial rotor offset in a final stage model of a three-stage centrifugal pump are carried out. The axial offset is intentionally given to shaft system to the both of discharge/suction side. As a result, the axial thrust is significantly affected by the axial offset in the flow rate range below 50% of the design. It is shown by CFD analysis that this effect of axial offset is caused by the interaction between the back flow from the diffuser and the main flow..
5.	De ZHANG, Yusuke KATAYAMA, Satoshi WATANABE, Shin-Ichi TSUDA, Akinori FURUKAWA, Performance prediction model of contra-rotating axial flow pump with separate rotational speed of front and rear rotors and its application for energy saving operation, Journal of Fluid Science and Technology, 10.1299/jfst.2020jfst0015, 2020.07.
6.	Y. Suzuki, Y. Katayama, S. Watanabe, S. Tsuda, A. Furukawa, A study on performance prediction of Darrieus-type hydroturbine operated in open channels using CFD with actuator disk method, IOP Conference Series: Earth and Environmental Science, 10.1088/1755-1315/240/4/042020, 240, 4, 2019.03, [URL], A performance of Darrieus-type hydroturbine is strongly influenced by the channel and flow condition. These flow conditions are different from place to place and also dependent upon the seasons, therefore it is difficult to study these influences only by experiments. On the other hand, numerical simulation can be adopted for various flow conditions. However, calculation costs are very expensive since fully unsteady simulation taking account of free surface of water should be conducted for this turbine as a cross-flow type. Then, in this paper, a simple numerical model is developed. In this model, instead of solving the complex flow field around the turbine, it is modeled by an actuator disk which imposes the total pressure difference consumed by the rotating turbine. Our previous study suggested that the head coefficient defined as the total pressure difference across the runner normalized by the dynamic pressure with area averaged flow velocity into the turbine seemed to well represent the specific performance of Darrieus-type hydroturbine. In this paper, the specific performance is determined from the experiment in one channel, and the corresponding total pressure change is locally applied to the actuator disk as a function of local inflow velocity. The predicted overall head coefficient, which is defined as the total pressure difference between far upstream and downstream normalized by area averaged velocity downstream of the turbine, is compared with experiment. As a result, when the flow velocity or depth decreases, the overall head coefficient increases. The proposed model can qualitatively reflect this influence of flow velocity and depth on the turbine performance in most cases, while quantitatively the predicted overall head coefficient is different from that in the experiments, indicating the necessity of further modification of the model for quantitative prediction..
7.	Keisuke Tsutsumi, Satoshi Watanabe, Shin ichi Tsuda, Takeshi Yamaguchi, Cavitation simulation of automotive torque converter using a homogeneous cavitation model, European Journal of Mechanics, B/Fluids, 10.1016/j.euromechflu.2016.09.001, 61, 263-270, 2017.01, To understand the flow mechanism of cavitation and its effect on the performance of automotive torque converter, numerical simulation considering cavitation is carried out at various turbine–pump speed ratios from 0 to 0.8. Since the cavitation in working fluid of torque converter is rather gaseous than vaporous, the partial pressure of air is applied to the cavity pressure in the simplified Rayleigh–Plesset cavitation model used in the present simulations. It is found that, for the lower speed ratios (0.6), the cavitation occurs at the pump inlet simultaneously or earlier than that at the stator. Once the cavitation occurs at the pump, the pump torque seems to drop suddenly..
8.	Satoshi WATANABE, Akinori FURUKAWA, Yoshiki YOSHIDA, Theoretical Analysis of Thermodynamic Effect of Cavitation in Cryogenic Inducer Using Singularity Method, International Journal of Rotating Machinery, Vol. 2008, Article ID 125678, 2008.06.
9.	Satoshi WATANABE and Christopher BRENNEN, Dynamics of Cavitating Propeller in a Water Tunnel, Transactions of ASME, Journal of Fluids Engineering, Vol. 125, No. 2, pp.283-292, 2003.03.
10.	Satoshi WATANABE，Yoshinobu TSUJIMOTO, Akinori FURUKAWA, Theoretical Analysis of Transitional and Partial Cavity Instabilities, Transactions of ASME, Journal of Fluids Engineering, 10.1115/1.1378295, 123, 3, 692-697, Vol.123, No.3, pp.692-697, 2001.09.

主要総説, 論評, 解説, 書評, 報告書等

主要学会発表等

1.	S. Watanabe, Cavitation Instabilities of Pumps: From Linear Analyses to Experimental Observations, 11th International Symposium on Cavitation (CAV2021), 2021.05, ポンプのキャビテーション不安定現象について，著者らが独自に開発・展開し，現象解明に貢献してきた線形解析および実験観察に関する取り組みを講演した．.
2.	松原瑞浦，渡部正夫，渡邉　聡，小西晃造，山口将平，橋爪　誠, バッドキアリ症候群のイメージベースド数値流体力学解析, 平成17年度日本生体医工学会九州支部学術講演会, 2006.03.
3.	松下直樹，古川明徳，大熊九州男，渡邉　聡, 高気液混合比用遠心ポンプ羽根車の揚水性能に及ぼす羽根高さの影響, 第54回ターボ機械協会（仙台）講演会, 2005.10.
4.	Hirokazu YAKUSHIJIN, Satoshi WATANABE, Hisasada TAKAHARA, Akinori FURUKAWA, Rotating Stall Behavior in Radial Vaneless Diffuser of Centrifugal Pump and Its Suppression, 2005 Asian Fluid Machinery, 2005.10.
5.	渡邉　聡，古川明徳，吉田義樹, 極低温インデューサに生じるキャビテーションの熱力学的効果の解析的検討, 日本機械学会第83期流体工学部門講演会, 2005.10.
6.	Tohru SHIGEMITSU, Tomoya TAKANO, Akinori FURUKAWA, Kusuo OKUMA, Satoshi WATANABE, Blade Rows Interaction of Contra-Rotating Axial Flow Pump Rotors in Pressure Field on Casing Wall, The 7th International Symposium on Experimental and Computational Aerodynamics of Internal Flow, 2005.09.
7.	Aknori FURUKAWA, Kazuki TAKENOUCHI, Kusuo OKUMA and Satoshi WATANABE, Utilization of Two-Dimensional Ducted Durrieus Turbine for Extra-Low Head Hydropower, EXPO World Conference on Wind Energy, Renewable Energy, Fuel Cell & Exhibition, 2005.06.
8.	Satoshi WATANABE, Tatsuya HIDAKA, Hironori HORIGUCHI, Akinori FURUKAWA and Yoshinobu TSUJIMOTO, Steady Analysis of Thermodynamic Effect of Partial Cavitation Using Singularity Method, 2005 ASME Fluids Engineering Summer Conference, 2005.06.
9.	Naoki MATSUSHITA, Akinori FURUKAWA, Kusuo Okuma and Satoshi WATANABE, Influences of Impeller Diameter and Diffuser Blades on Air-Water Two-Phase Flow Performance of Centrifugal Pump, 2005 ASME Fluids Engineering Summer Conference, 2005.06.
10.	古川明徳，高野倫矢，重光　亨，大熊九州男，渡邉　聡, 二重反転形軸流ポンプのケーシング壁面静圧計測, 第53回ターボ機械協会総会講演会, 2005.05.
11.	Jun-Ho KIM, Masao ISHIZAKI, Naoki ENOMOTO, Kouichi ISHIZAKA, Satoshi WATANABE and Akinori FURUKAWA, Suppression of Cavitation Surge of Inducer by Inserting Axi-asymmetric Obstacle Plate, 6th JSME/KSME Fluids Engineering Conference, 2005.03.

所属学会名

学協会役員等への就任

学会大会・会議・シンポジウム等における役割

学会誌・雑誌・著書の編集への参加状況

学術論文等の審査

海外渡航状況, 海外での教育研究歴