CFD ANALAYSIS OF FLOW THROUGH A CONICAL EXHAUST DIFFUSER

Abstract

The exhaust diffuser of a fluid machine such as a gas turbine recovers static pressure by decelerating the flow and converting kinetic energy into pressure energy. It is hence a critical component in a turbo machine environment and plays a pivotal role in determining the performance of a turbo machine. Therefore, if the diffuser design is optimized for maximum pressure recovery, an increase in efficiency of the fluid machine can be brought about. Computational fluid dynamics (CFD) analysis was performed on diffusers with different half cone angles and based on the results obtained the geometry that yielded the maximum pressure recovery was identified. The diffuser with the optimized geometry was then fabricated and tested. The experimental value of the diffuser pressure recovery coefficient was calculated and compared with the theoretical value.