均匀剪切稳定分层流动中湍流特性的数值研究

Large Eddy Simulation of Turbulence Properties in a Uniformly Sheared and Stably Stratified Flow

采用大涡模拟的方法,研究了均匀剪切稳定分层流动.主要对不同梯度Richardson数下湍流动量和标量输运特性进行分析研究.结果表明:随着梯度Richardson数的增大,湍流动能减小,湍流势能增大;垂向热通量和雷诺应力减弱,流向热通量增强;并且在强分层情况下,存在动量和热量的逆梯度输运现象.

LES method is applied to study the sheared homogeneous stratified turbulent flows.The turbulent momentum and scalar transport properties of different gradient Richardson numbers are mainly analyzed.The primary conclusions are:with the increase of gradient Richardson number,turbulent kinetic energy decreases,while the turbulent potential energy increases;vertical heat flux and the Reynolds stress decrease,but the streamwise heat flux increases;Turbulent momentum and heat CGT in strong stratification are more obvious than those of the weak stratified turbulence.