Two-equation turbulence modelling of a transitional separation bubble

Calculations of the Reynolds averaged equations using two different turbule nce models have been compared with direct numerical simulation of a transit ional separation bubble. Three methods of transition modelling were investi gated. The first had no transition adjustment, the second involved fixing t he transition point at the location observed in the simulation and the thir d was a direct transformation of a method proposed by Wilcox [1] which invo lved sensitising the eddy viscosity and transport equations to the local tu rbulent Reynolds number. The models captured the general features of the fl ow but were unable to show the recovery behaviour of the flow behind the bu bble. Reasons for the failure are discussed using a priori analysis of term s in the model equations.