Difference Between Active(Heat)-and passive Scalar Diffusions in Thermally Stratified Flow

热分层流中主动（热）和被动标量扩散之间的差异

• 批准号: 61550176
• 负责人: UEDA Hiromasa
• 金额: $ 1.47万
• 依托单位: National Institute for Environmental Studies
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (C)
• 财政年份: 1986
• 资助国家: 日本
• 起止时间: 1986 至 1987
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-61550176/
• 关键词: Stratified flow; Scalar diffusion; Active-scalar; Turbulent boundary layer; Burger's turbulence; Fine structure turbulence; 乱流微細構造; 濃度変動測定

In the thermally stratifed flows temperature fluctuation induces buoyancy force and causes drastic changes in turbulence structure and transport porcesses.When the stratification is extremely stable,for example,it causes a counter-gradient diffusion of heat.However,mass(e.g.diluted pollutant) usually diffuses in the direction of its concentration gradient,even in such a flow field.The purpose of the present study is to make clear experimentally and theoretically the difference between the active-scalar(heat)and passive scalar diffusions.1.Experimental investigation on scalar diffusion mechanisms:First a simultaneous measuring technique of two-species concentration fluctuations was established,which was besed on the laser-induced luminescence and Mie-scattering and consisted of a line-or area-photodetectory array.Superiority of this technique was confirmed by

在热分层流动中，温度波动引起浮力，引起湍流结构和输运过程的剧烈变化。例如，当分层非常稳定时，它会引起热的反梯度扩散。被稀释的污染物)通常沿其浓度梯度的方向扩散，即使在这样的流场中也是如此。本研究的目的在于从实验和理论上明确主动标量（热）扩散与被动标量扩散的区别。标量扩散机理的实验研究：首先建立了一种基于激光诱导发光和米氏散射的两种浓度波动同时测量技术，该技术由线或面光电探测阵列组成。实验证明了该技术的优越性

项目成果

Ueda,H.,Komori,S.& Kitada,T.: "Transport phenomena in the thermalinternal boundary layer." World Congress III of Chemical Engineering,. Vol.3,. 678-681. (1986)

上田，H.，小森，S.

Satoru KOMORI: World Congress III of Chemical Enginnring. 2. 320-323 (1986)

小森悟：第三届世界化学工程大会。

Komori,S.,Sawano,R.& Ueda,H.: "Coherent structures associated with bursting events in the wall region of open-channel flow." World Congress III of Chemical Engineering,. Vol.2,. 320-323. (1986)

小森，S.，泽野，R.

Komori,S.,Hiraga,Y.,Murakani,Y.& Ueda,H.: "Relationship Between surface renewal and bursting motions in and open-channel flow." Journal of Fluid Mechanics. (1988)

小森 S.、平贺 Y.、村上 Y.

Hiromasa Ueda;Satoru Komori;Toshihiro Kitada: World Congress 【III】 of Chemical Engineering. 3. 678-681 (1986)

Hiromasa Ueda；Satoru Komori；Toshihiro Kitada：化学工程世界大会 [III] 3. 678-681 (1986)。