Flow control technology using multi-scale characteristics of three-dimensional complexity wakes

2018 Fiscal Year Final Research Report

• Project/Area Number: 16K06067
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Fluid engineering
• Research Institution: Yamagata University
• Principal Investigator: RINOSHIKA AKIRA 山形大学, 大学院理工学研究科, 教授 (00253906)
• Project Period (FY): 2016-04-01 – 2019-03-31
• Keywords: 後流 / 渦 / 流れ制御

Outline of Final Research Achievements

In this study, 2DPIV was used to measure and visualize the instantaneous velocity of the flow field around several bodies. The shape, number, height and arrangement of the objects were investigated in relation to the vortex structures. In order to study the shape of the new breakwater, we conducted an experimental study on the wake structures of a square cylinder with a wave-shaped surface. In the wake of the wave shape model, it was found that the low velocity area and the separation region generated were enlarged. Three-dimensional PIV measurements were performed on three-dimensional flow around a low aspect ratio cylinder used for the new breakwater. We elucidated the formation, interference and attenuation processes of the three-dimensional vortex, and extracted large-scale vortices that dominate new breakwaters.

Free Research Field

流体工学

Academic Significance and Societal Importance of the Research Achievements

本研究は多数の低アスペクト比の物体が発生した三次元渦構造や渦励振の機構などを解明するともに、渦の制御という観点から効果的に津波のエネルギーを消散させる新たな構造の防波堤に応用できる。防波堤の高さを抑制する経済効果とともに、防災・減災などの国土強靱化に結びつき、非常に特色のある基礎・応用研究である。また、悲惨な自然災害から「命を守る」と「減災」の基本対策より、本研究は国の防災上にも重要な研究といえる。