Numerical Investigation of Flow within a Model Steam Ejector using Computational Fluid Dynamics

Steam jet refrigeration is a refrigeration system that uses water as working fluid. It utilizes a low temperature thermal energy (100-200°c) from inexpensive sources such as industrial wasted heat. The major component that makes the system applicable is a steam ejector. It is found that the performance of the system depends on the performance of the ejector. Therefore, in order to improve the performance of an ejector, understanding the flow behavior inside the ejector is necessary. In this paper, Computational Fluid dynamics was used to analyze the supersonic flow behavior inside a steam ejector aiming to reveal the complication of flow and mixing process at different part of steam ejector particularly its convergent - divergent nozzle. The effect of choking process on ejector performance was also investigated. This simulation was done using the simulation software package (Fluent). Using Fluent, flow structure of the modeled ejectors can be shown graphically and the phenomena can be explained.

Keywords:

Steam Ejector , Entrainment Ratio , Flow Simulation , Computational Fluid Dynamics