Similarity characteristics of qualitative and quantitative regulation for adjustable ejector

Abstract

In the new era of ejector technology entering into system scale from device scale. The methodology of regulation mode of adjustable ejector has been summarized in the paper. The similarity characteristics of qualitative and quantitative regulation under different operating modes are researched. The results show that both quantitative and quantitative regulation have the characteristics of "constant capacity". Three different “constant capacity” phenomena in ejector have been found, and the similarity indicates that the turbulent flow in ejector has some statistical invariances in form of mass flow rate of jetting flow. The ejector has the similar entrainment ability by increasing primary pressure by 43% in qualitative regulation mode or enlarging the nozzle throat opening by 47% in quantitative regulation mode under critical mode with similar under-expanded state. The advantages of adjustable ejector have been promoted, especially ±5% regulation accuracy or really constant regulation ability, discharging improved ability by 80% in flow rate or 10% in pressure lifting ability in subcritical mode, or primary flow rate saving ability by 25% or 13% in pressure lifting ability in critical mode.