Breakdown过程长度及其前后边界层名义厚度的变化

唐洪涛

Breakdown过程长度及其前后边界层名义厚度的变化

唐洪涛

天津科技大学机械工程学院, 天津 300222;天津大学力学系, 天津 300072

基金项目: 天津科技大学引进人才科研启动基金(20070426);国家自然基金资助项目(90205021)

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出版历程
- 收稿日期: 2007-04-15
- 修回日期: 2007-07-02
- 刊出日期: 2008-05-28

Durations of transition and variation of boundary-layer thickness before and after breakdown

TANG Hong-tao

School of Mechanics Engineering, Tianjin University of Science and Technology, Tianjin 300222, China;Department of Mechanics, Tianjin University, Tianjin 300072, China

摘要

摘要: 采用数值模拟的方法,模拟了平板边界层的转捩过程及发展的湍流,在此基础上,研究了不同初始扰动对转捩持续时间和湍流边界层厚度影响的共性和差异.研究结果表明:在不同的波数情况下,计算得到不同的初始扰动引起的转捩的持续时间不同.在给定基本波数情况下,如果初始扰动在展向不是对称的,那么,它们引起的转捩后平均边界层厚度与转捩起始点处边界层厚度的比值δ_e/δ_b在相当长的时间内表现出相同的增长规律,这一增长规律与所加的初始扰动无关.然而,展向是非对称的表现出不同增长规律.
- 航空、航天推进系统 /
- 转捩 /
- 湍流 /
- 波数 /
- 扰动
Abstract: Temporal mode direction numerical simulation has been done for the breakdown process of laminar-turbulent transition and the fully developed turbulence in an incompressible boundary layer on a flat plate.Based on the computational results,the common and different characteristics of the durations of transition and the time-averaged boundary-layer thickness induced by different initial disturbances were discussed.Analytical results show that under different basic wave numbers,the durations of transition induced by different initial disturbances are different to one another.On the other hand,under given basic wave numbers,if the initial disturbances are dissymmetrical in span-wise direction,the ratio of the time-averaged boundary-layer thickness after transition to the boundarylayer thickness at the beginning of the breakdown process in the transition,δ_e/δ_b,shows the same growth rate with respect to time,which is independent of the initial disturbances.In contrast,initial symmetric disturbances will induce different growth trends.
- aerospace propulsion system /
- transition /
- turbulence /
- wave number /
- disturbance

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参考文献(10)

[1]	Saric W S.Physical description of boundary layer transition[R].Experimental Evidence,In AGARD-CP-793,1994.
[2]	Thibert J J,Reneaux J,Schmitt V.Onera activities in drag reduction[J].Congr.Int.Counc.Aeron.Sci.(ICAS)1990,17:1053-1064.
[3]	张涵信,周恒.流体力学的基础研究[J].世界科技研究与发展,2001,23(1):15-18.ZHANG Hanxin,ZHOU Heng.On basic research of fluid mechanics[J].World Sci-tech R & D,2001,23(1):15-18.
[4]	周恒.新世纪对流体力学提出的要求[J].自然科学进展,2000,10(6):491-494.
[5]	郑哲敏,周恒,张涵信.21世纪初的力学发展趋势[J].力学进展,1995,25(4):433-441.ZHENG Zemin,ZHOU Heng,ZHANG Hanxin.Trends of development in mechanics in the early 21st century[J].Advances in Mechanics,1995,25(4):433-441.
[6]	周恒,赵耕夫.流动稳定性[M].北京:国防工业出版社,2004.
[7]	LUO Jisheng,WANG Xinjun,ZHOU Heng.Inherent mechanism of breakdown in laminar-turbulent transition of plane channel flows[J].Science in China,Set.G,2005,48(2):228-236.
[8]	唐洪涛.不可压缩乎板边界层从层流突变为湍流的机理及湍流特性[D].天津:天津大学,2007.
[9]	HUANG Zhangfeng,ZHOU Heng,LUO Jisheng.Direct numerical simulation of a supersonic turbulent boundary layer on a flate plate and its analysis[J].Science in China,Ser.G,2005,48(5):626-640.
[10]	Lundbladh A,Schmid P J,Berlin s.Simulation of bypass transition in spatially evoldng flows[R].AGARD-CP 551,1994.