Bypass ejector with an annular cavity in the nozzle wall to increase the entrainment: Experimental and numerical validation

A bypass ejector geometry with an annular cavity in the nozzle wall was tested for various operating conditions to evaluate the entrainment performance. The results were compared with those of a conventional ejector. The data shows that the primary mass flow rate in the bypass ejector is always about 20% less than that in the conventional ejector. The results show that the bypass ejector is better than the conventional ejector at relatively high primary and secondary flow pressures with a maximum improvement in the entrainment performance of 31.5%. The bypass ejector has better entrainment performance in the critical mode. Since most ejectors operate in the critical mode, this ejector will have many applications requiring more entrainment.