Developments in a low-Reynolds-number second-moment closure and its application to separating and reattaching flows

The paper describes further developments of the low-Reynolds-number second-moment closure of Craft and Launder (1996), and reports its application to separating and reattaching flows. The specific flows considered are the axisymmetric diffuser flows of Stieglmeier et al. (1989), and the backward facing step flows reported by Driver and Seegmiller (1983) and Le et al. (1997). It is shown that modifications to the pressure strain model, including inhomogeneity effects on the mean velocity gradients, allow the large shear stress values found experimentally in the recirculation region to be captured. An elaboration of the (algebraic) approximation for the triple moments is also proposed which improves the prediction of the recirculation and recovery region. (C) 1998 Elsevier Science Inc. All rights reserved.