Flow characteristics of a converging nozzle flow with sudden expansion at sonic Mach number

Newaz, Md Ashif and Bellary, Syed Ahmed Imran and Khatawate, Vinayak Hanmantasa and Shetty, Shamitha and Khan, Sher Afghan (2025) Flow characteristics of a converging nozzle flow with sudden expansion at sonic Mach number. Perinatal Journal, 33 (1). pp. 449-466. ISSN 1305-3124

PDF - Published Version Restricted to Repository staff only Download (1MB) | Request a copy

Abstract

The development of space shuttles and high-performance military aircraft has made studying turbulent flow in a separated region a vital topic of study. Researchers are also interested in turbulent flow in transonic and supersonic flow. There is considerable relief for the flow when it separates and expands once the area of the larger duct suddenly increases. There are two areas where the shear layer emerges: the separated flow and the main flow. Considerable drag results from the split streamline reattaching to the duct, creating a recirculation zone where the pressure is lower than the surrounding air. Flow from a converging nozzle is suddenly exhausted to a larger diameter. The duct diameter is 22 mm. Base pressure management using a D-shaped rib as a passive control mechanism is the primary focus of this study. The passive control was located at various positions, with a length-to-diameter ratio (L/D) of 0.5, 1, 1.5, 2, and 3. Numerical simulations were conducted for rib radii of 0.5, 1, and 1.5 mm. Results indicated that the D-shape rib with a 0.5 mm radius is ineffective, except at nozzle pressure ratios of 4 and 5. The maximum increase in the base pressure is attained for a rib radius of 1.5 mm, and a very moderate rise is obtained for a 1 mm radius. It is observed that the rib locations at L/D = 2 and 3 are ineffective, as the flow becomes attached to the wall around L/D = 1 to 1.5. Hence, one can select the rib radius and height based on the user's requirements.

Item Type:	Article (Journal)
Uncontrolled Keywords:	Base pressure, L/D ratio, Nozzle pressure Ratio, Sonic Mach number, Base drag
Subjects:	T Technology > TL Motor vehicles. Aeronautics. Astronautics > TL780 Rockets
Kulliyyahs/Centres/Divisions/Institutes (Can select more than one option. Press CONTROL button):	Kulliyyah of Engineering > Department of Mechanical Engineering Kulliyyah of Engineering
Depositing User:	Prof. Dr. Sher Afghan Khan
Date Deposited:	09 Sep 2025 12:14
Last Modified:	09 Sep 2025 12:14
URI:	http://irep.iium.edu.my/id/eprint/123085

Actions (login required)

View Item