CFD analysis of a supersonic air ejector. Part I: Experimental validation of single-phase and two-phase operation

This paper deals with comparisons between CFD and experiments for a supersonic ejector. Good results are presented in terms of entrainment rate compared to home-made experimental data for an air ejector. Over the whole range of operating conditions, the overall deviation is below 10% for the k-ϵ model, while the results for the k-ω-sst model are in a less agreement. Furthermore, it is demonstrated that the validation of a global performance parameter, such as the entrainment rate, is not sufficient for a correct assessment even though a wide range of operation is tried out. Indeed, for exactly the same prediction both models may give very different local flow features. Finally, a first attempt to tackle two-phase aspects was also performed experimentally and by simulations.