Experimental and computational analysis for air-ejector of liquid ring vacuum pump

The flow field of the air-ejector of liquid ring vacuum pump is 3D simulated by applying the Computational Fluid Dynamics (CFD) technique. According to the simulation results, the relationship between suction pressure and mass flow rate of suction fluid is obtained. Compare with the experimental results, it is verified that the numerical simulation method adopted in this paper is feasible. Then using the simulation method to analyze the influence of the outlet pressure and suction pressure on the performance of the air-ejector. The result show that: When the motive pressure and the suction pressure are constant, there is a critical outlet pressure Pd*, which corresponds to the optimum working point of the air-ejector, which can provide a reference for determining the outlet pressure in ejector design. When the motive pressure and outlet pressure are constant, the entrainment ratio and air-ejector efficiency increase with the suction pressure, but the vacuum capacity of the air-ejector decreases and the application range becomes smaller.