Numerical investigation on performance optimization of steam ejector considering full geometric parameters and working conditions

Abstract

As an energy-saving device for energy transduction, a steam ejector has been crucial in energy saving and emission reduction, energy consumption reduction, and energy reuse. An optimization method of full geometric parameters and a preferred method of working conditions were considered to rise the entrainment ratio of a steam ejector and improve its entrainment capacity. The related models of the ejector were established and numerically simulated. The influence of geometric parameters on the entrainment capacity of the ejector researched by adopting the control variable method and the 11-factor 5-level orthogonal test. The effect of working conditions on the entrainment ratio for the optimized ejector discussed, and the preferred method of working conditions of the ejector proposed. The results show that the entrainment ratio of the optimized ejector by the control variable method rises by 30.8 % to that of the original ejector, and the entrainment ratio of the new ejector by orthogonal test rises by 78 %. The constant cross-section diameter is a critical parameter affecting the entrainment capacity of the ejector. Contrasted with the original ejector, the maximum entrainment ratio under preferred working conditions rises by 242%–471 % via using the preferred method of working conditions. Considering the optimization of full geometric parameters and working conditions, the influence of the optimized process on the entrainment capacity of ejectors is evident, which provides an effective way and reference for the optimization research and development of other types of ejectors.