Numerical Study on a Conical Diffuser with Inlet Swirl

Abstract:

One of the major components of axial-flow compressors and turbines are the diffusers, employed for the conversion of fluid velocity to pressure. They are used in gas turbines, pumps, wind tunnels and other fluid flow devices. Diffusers are used in jet engines, aircraft engines for various purposes. Usually a diffuser is considered as an isolated component for the ease of computation. However, when there is upstream machinery, the effect of flow separation cannot be neglected and hence considering a diffuser as an isolated component would not suffice. The effect of swirl on the performance of a conical diffuser is taken into consideration. Pressure recovery co-efficient indicates the performance of the system and its values are studied under various inlet condition still ideal case is reached and various flow parameters for this ideal case are noted. Ideal condition is the one in which the energy losses along the sections of a diffuser are minimum. This paper provides a holistic view of the flow through a diffuser, laying primary emphasis on the effect of inlet swirl.

• Periodical: Applied Mechanics and Materials (Volume 852)
• Pages: 688-692
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.852.688
• Online since: September 2016
• Authors: R. Prakash*, N. Karthiek, P. Ashwath, H. Anand, G. Adithya
• Keywords: Conical Diffuser, Divergence Angle, Inlet Swirl, Swirl Number, Turbulence, Turbulent Kinetic Energy

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