SINOPSIS

A second-moment-closure model, selected following a preliminary study of several models of the same class, is subjected to extensive a-priori analysis in a flow separating from a curved surface, leading to a newly proposed corrections aimed specifically at the separated shear layer. The analysis includes a separate examination of the dissipation-rate equation, the dissipation anisotropy and the pressure-strain correlation, with the aim of clarifying the validity and effectiveness of various components therein. This is done by reference to highly-resolved LES data recently generated by Lardeau et al. (2011) for a canonical turbulent boundary layer separating from a curved ramp, with results including a complete set of second-moment budgets. The nature of the a-priori tests is described, and the outcome discussed.