Scaling Boundary-Layer Profile of Turbulent Wall Flows with Mass Transfer

Direct numerical simulations have been carried out to investigated the effcet of surface mass transfer on the temperature and velocity in turbulent boundary layers. The theories based on the linear boundary layer equations show that the thickness of the sublayer increases in the presence of surface blowing; therefore, the viscous sublayer and law of the wall modify. It is hypothesized that the blowing process affects the heat transfer rate in the boundary layer. We develop a model that scales the full profile of velocity and temporeture using DNS. Emphasis is placed on moderate and high mass transfer rates, which are relevant to the most common hybrid rocket configuration. In this study, direct numerical simulations (DNS) of turbulent boundary layers with uniform surface mass transfers are carried out in order to scale the velocity profile. Emphasis is placed on moderate and extreme mass transfer rates. DNS data is used to establish a functional law of the wall by means of the relation between the wall shear stress, the Reynolds number, and the transpiration velocity.