Mixed Convection in Three Dimensional Separated Flow

主要研究人员对后向台阶三维几何结构中分离流区和再附流区的流动和换热进行了协调的实验和数值研究。在利用液晶热像仪测量换热系数的同时，将使用激光多普勒测速仪同时测量局部速度分量。重点将放在确定传热和浮力对平均速度分量和波动速度分量的影响上。将确定雷诺剪应力、法向应力和换热系数。后向台阶将用于流动形态，因为它包含了三维分离流动区域中遇到的大多数复杂问题：自由剪切层；强烈的逆压梯度；剪切层和壁面的相互作用；以及再附着。

The principal investigator proposes a coordinated experimental and numerical study of the flow and heat transfer in the separated and reattached flow regions in the three dimensional geometry of a backward facing step. A laser-Doppler velocimeter will be used to measure the local velocity components simultaneously with the measurement of the heat transfer coefficient using liquid crystal thermography. The focus will be on determining the effect of the heat transfer and the buoyancy on the mean and fluctuating velocity components. Reynolds shear stresses, normal stresses, and heat transfer coefficients will be determined.The backward facing step will be used for the flow configuration since it contains most of the complexities that are encountered in three dimensional separated flow regions: a free shear layer; strong adverse pressure gradient; interaction of the shear layer and the wall; and reattachment.