General method for determining the boundary layer thickness in nonequilibrium flows

Abstract

In this work, a new method for computing the boundary layer thickness is proposed by reconstructing an approximate inviscid solution based on the Bernoulli equation. The viscous streamwise velocity profile $U[y]$ agrees with this inviscid reconstruction ${U}_{I}[y]$ outside the boundary layer, and the solutions diverge from each other at the boundary layer edge. The boundary layer thickness is readily determined by examining the discrepancy between these profiles. Extensive validation suggests that the present method is more robust and more widely applicable than existing methods.