3-Dimensional Structure of Eddy in Free Turbulence Flow

Research Project

Project/Area Number	61550710
Research Category	Grant-in-Aid for General Scientific Research (C)
Allocation Type	Single-year Grants
Research Field	化学工学
Research Institution	Kyushu Institute of Technology
Principal Investigator	YUU Shinichi Faculty of Engineering, Kyushu Institute of Technology, 工学部, 教授 (30026215)
Project Period (FY)	1986 – 1987
Project Status	Completed (Fiscal Year 1987)
Budget Amount *help	¥1,600,000 (Direct Cost: ¥1,600,000) Fiscal Year 1987: ¥400,000 (Direct Cost: ¥400,000) Fiscal Year 1986: ¥1,200,000 (Direct Cost: ¥1,200,000)
Keywords	Developing Turbulence / Large Scale Vortices / Free Jet / Velocity Vector Diagram / 2点間速度相関 / 自由乱流 / 乱流の遷移 / 渦の合一 / 大規模流れの干渉
Research Abstract	A series of measurements was made simultaneously by using arrays of hot-wire anemometers with X-probes. The data show the rows consisted of doughnut-type large-scale vortices and their frequent pairing which results in larger vortices. The interaction of these vortices beyond the jet centrline breaks the doughnut-type large-scale vortices and forms three-dimensional medium and small-sized vortices. The flow is randomized through this process. Some large scale vortices continue to pair and form the configuration of counter-rotating vortices approximately alternating on opposite sides of the jet centerline in the region far from the nozzle.