A Study on Improvement of Performance of Ship Propulsion Device Directly Driven by Steam

蒸汽直驱船舶推进装置性能改进研究

• 批准号: 13450077
• 负责人: TSUTAHARA Michihisa
• 金额: $ 3.39万
• 依托单位: Kobe University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 2001
• 资助国家: 日本
• 起止时间: 2001 至 2003
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-13450077/
• 关键词: Shin propulsion device; Flow inside nozzle; Unsteady flow; Air-water two-phase flow; Flow visualization

By visualizing the flow inside the nozzle by high-speed video camera, it is shown that the flow is not a mixed flow of air and water but a flow in which the air and the water are separated and waves with large amplitude appear on the interface. These waves close the air flow and the pressure rises and the pressure accelerate the water, towards downstream. It is also shown that the mechanism in accelerating the water is not mixing but the volume of water accelerated by air pressure without mixing. So the loss is smaller than the mixing mechanism. The case of intermittent emission, the thrust itself does not increase, but the propulsive efficiency considering the emission duration, the operation of intermittent emission is better.The numerical simulation by the finite difference lattice Boltzmann model for two fluids gives good results. On the interface between the two fluids, large-amplitude waves appear. But in this model the densities of the two fluids are the same, then we tried to improved the two-fluid model. The density difference corresponds to the acceleration difference, so by modifying the acceleration the density difference can be simulated. For single-phase flows, this technique is shown to be successful. A new model with choosing specific heats for multi-atomic gas is also introduced.

利用高速摄像机对喷嘴内的流动进行可视化观察，表明该流动不是空气和水的混合流动，而是空气和水分离的流动，并且在界面上出现了振幅较大的波。这些波浪阻断了气流，压力上升，压力加速了水流，流向下游。还表明，加速水的机理不是混合，而是空气压力加速的水体积没有混合。所以损失比混合机制要小。间歇发射的情况下，推力本身不增加，但从推进效率考虑发射持续时间，间歇发射的运行效果更好。用有限差分晶格玻尔兹曼模型对两种流体进行数值模拟，得到了较好的结果。在两种流体的界面上，出现了振幅较大的波。但在该模型中，两种流体的密度是相同的，因此我们尝试对两种流体模型进行改进。密度差对应加速度差，因此通过修改加速度可以模拟密度差。对于单相流，该技术是成功的。介绍了一种新的多原子气体比热选择模型。

项目成果

M.Tsutahara, K.Ogawa, M.Sakamoto, T.Matsui: "Nozzle flow of a ship propulsion equipment driven by high-pressure gas"Proceedings of FEDSM'03,4TH ASME_JSMEJOINT FLUIDS ENGINEERING CONFERENCE. (CD-ROM)F-311TOC. FEDSM2003-45092 (2003)

M.Tsutahara，K.Okawa，M.Sakamoto，T.Matsui：“高压气体驱动的船舶推进设备的喷嘴流动”FEDSM03，第4届ASME_JSMEJOINT流体工程会议论文集。

蔦原道久: "差分格子ボルツマン法における新しいモデル"日本機械学会論文集B. 68巻665号. 15-21 (2002)

茑原道久：“微分格子玻尔兹曼法的新模型” 日本机械工程学会会刊 B. Vol. 68，No. 665. 15-21 (2002)

Michihisa Tsutahara, Kazuhiko Ogawa, Masahiko Sakamoto, Takahiro Matsui, Shinsuke Tajiri, Masakazu Tajima: "Simulation of flows in a semi-open-type nozzle for ship s propulsion equipment by the finite difference lattice Boltzmann method"Proceedings of Thi

Michihisa Tsutahara、Kazuhiko Okawa、Masahiko Sakamoto、Takahiro Matsui、Shinsuke Tajiri、Masakazu Tajima：“通过有限差分格子玻尔兹曼方法模拟船舶推进设备半开式喷嘴中的流动”Thi 论文集

M.Tsutahara, K.Ogawa, M.Sakamoto他3名: "Simulation of flows in a semi-open-type nozzle for ship's propulsion equipment by the finite difference lattice Boltzmann method"Proceedings of third international workshop on ship hydrodynamics. (Accepted). (2003)

M. Tsutahara、K. Okawa、M. Sakamoto 等 3 人：“Simulation of flow in a semi-open-type酷喷嘴用于船舶推进设备，采用有限差分格子玻尔兹曼法”第三届国际船舶流体动力学研讨会论文集（已录用。 ）（2003）。

M.Tsutahara, K.Ogawa, M.Sakamoto: "Study of Ship Propulsion Equipment Directly Driven by Steam"Proceedings of second international workshop on ship hydrodynamics. September. 94-101 (2001)

M.Tsutahara、K.Okawa、M.Sakamoto：“蒸汽直接驱动船舶推进设备的研究”第二届国际船舶流体动力学研讨会论文集。