Experimental and Computational Investigations on Flow Characteristics of Supersonic Ejector

Experimental and computational investigations have been conducted to characterize the flow field in the supersonic ejector, with and without secondary inlets of two sizes, at stagnation pressures of 2, 2.5, 3, 4 and 5 bar. In the first case, four secondary inlet openings each with 5 mm diameter are provided on the suction chamber circumferentially. In the second case, four secondary inlet openings each with 10 mm diameter are provided on the suction chamber circumferentially. These two cases are investigated separately, at all the stagnation pressures.  The wall pressure variation is validated based on the k-ω SST turbulent model with experimentally measured wall pressure distribution at 2 bar, without secondary inlet flow.  Suction is found to increase with the increase of stagnation pressure in the suction chamber. The inducted mass flow promotes the mixing in the shock-train zone, by triggering the significant momentum exchange between the primary flow and secondary flow. Results show that the pressure recovery takes place as the flow enters the divergent portion of ejector.