Optimization of Ejector Geometric Parameters Using CFD

International audienceCompression of a low pressure vapor without any rotating parts or direct external power sources is possiblethrough a supersonic ejector. A high pressure vapor leads the compression of the low pressure vapor bypure fluid mechanics. Entrainment ratio is a major characteristic of the ejector performance and is highlydependent on its geometry. Based on pre-specified operating conditions, the flow behavior inside the ejectoris studied by using computational fluid dynamics "CFD" "ANSYS FLUENT 15.0" software. The aim of thispaper is to design ejector geometry and assess and quantify the impact on performance of geometry ofejectors. First a 1-D mathematical model is carried out to predict the ejector geometry, meaning thediameters of each zone. Second, the 1-D model results are converted into 2D figures and studied in CFD.Major challenge is to reveal the mixing process at different parts of the supersonic turbulent flow and to studythe effect of the geometry on the effective ejector area. Results show the effect of the geometry on theentrainment ratio, in particular the length of ejector throat