Analysis of Flow Behaviour in a Jet Ejector Using CFD

Abstract

This work is concerned with the analysis of flow behaviour in a jet ejectors using Computational Fluid Dynamics (CFD) tools. Jet ejectors are the best devices among all compressors and vacuum pumps. The Ejector includes three most important parts namely, nozzle, mixing chamber and diffuser. In the present work designing and meshing of the ejector components are performed in GAMBIT and parts are exported to an evaluation software. The use of the geometrical design parameters obtained via fixing governing equations using the analysis done by FLUENT software to assess the greatest entrainment ratio that would be performed for a given set of operating conditions, in which the entrainment ratio (ER) is the ratio of the mass flow rate of the secondary fluid to the primary fluid. In the present work, we studied the flow behaviour of constant area ejector and constant pressure ejector further analyzed with different motive fluids. Distinct contours and vectors are plotted and their flow behavior on the corresponding jet ejectors are studied. It is also concluded that motive fluid containing larger molecular weight will have an effect on the ejector performance.