Entrainment boundary conditions for free shear flows

In this paper the performance of different free stream boundary conditions has been investigated. By performing two dimensional free jet calculations, a test case for which an analytical solution is available, it has been sho wn that boundary conditions in which the pressure is prescribed perform sig nificantly better than boundary conditions in which the velocity is prescri bed. Furthermore, it has been shown that pressure boundary conditions allow for much smaller computational domains than velocity (free-slip) boundary conditions.