Choosing the optimal operation conditions for differential gas ejectors

Abstract

Instead of a system of gas ejectors, S.A. Khristianovich proposed a scheme of a differential ejector in which the ejecting gas injection is continuously distributed along channel walls. B.A. Uryukov [1] described the ejector model, presented differential equations of the model, analyzed them, and obtained the optimal operation conditions for the differential ejector. In addition, the author presented results of calculating some variants that are most interesting in his opinion. A more recent work [2] is concerned with analyzing systems of gas ejectors and a differential ejector, where the author points to incomplete correspondence of the Khristianovich-Uryukov model to the real process in the ejector and presents some additional (with respect to results of [2]) contentions relative to optimality. The Khristianovich equations were obtained under assumption of averaging all gas parameters over channel section without time shift, i.e., a one-dimensional scheme of flow is considered, which is justified for preliminary analysis of the processes. Differential equations reflect three laws of conservation and variation of mass, energy, and momentum. The study of gas ejector equations was done in [1] analytically, for this reason, some important peculiarities of flows, which can be analyzed by numerical methods, were not considered. In the proposed work, we analyzed by analytical methods some optimality conditions proposed in [1, 2] and found new flow regimes in gas ejectors, which lead to higher values of compression ratio.