Open Access

ARTICLE

Passive Control of Base Pressure in a Converging-Diverging Nozzle with Area Ratio 2.56 at Mach 1.8

by Nur Husnina Muhamad Zuraidi¹, Sher Afghan Khan^1,*, Abdul Aabid^2,*, Muneer Baig², Istiyaq Mudassir Shaiq³

1 Department of Mechanical Engineering, International Islamic University Malaysia, P.O. Box 10, Kuala Lumpur, 50728, Malaysia
2 Department of Engineering Management, College of Engineering, Prince Sultan University, P.O. Box 66833, Riyadh, 11586, Saudi Arabia
3 School of Aerospace Engineering, Engineering Campus, Universiti Sains Malaysia, Nibong Tebal, Pulau Pinang, 14300, Malaysia

* Corresponding Authors: Sher Afghan Khan. Email: ; Abdul Aabid. Email:

(This article belongs to the Special Issue: Materials, Energy, and Fluid Dynamics)

Fluid Dynamics & Materials Processing 2023, 19(3), 807-829. https://doi.org/10.32604/fdmp.2023.023246

Received 14 April 2022; Accepted 08 July 2022; Issue published 29 September 2022

Abstract

In this study, a duct is considered and special attention is paid to a passive method for the control of the base pressure relying on the use of a cavity with a variable aspect ratio. The Mach number considered is 1.8, and the area ratio of the duct is 2.56. In particular, two cavities are examined, their sizes being 3:3 and 6:3. The used L/D spans the interval 1–10 while the NPRs (nozzle pressure ratio) range from 2 to 9. The results show that the control becomes effective once the nozzles are correctly expanded or under-expanded. The pressure contours at different NPR and L/D are presented. It is shown that the NPR and cavity location strongly influence the base pressure. The NPR, Mach number, and cavity aspect ratio have a strong effect on the base pressure in the wake region.

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Keywords

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