Work

Passive control of sonic flow from converging nozzle with D-shaped rib

Year: 2025

Type: article

Abstract: • Novel d-shaped ribs enhance passive control in high-speed flow expansion. • Optimal rib placement improves base pressure stability and flow uniformity. • A comprehensive CFD simulations considering different parameters of the current work. • Findings support improved aerodynamic efficiency for aerospace applications. The abrupt expansion at the blunt base of projectiles, rockets, missiles, etc., is a common phenomenon. Flow separation and reattachment are caused by the abrupt increase in the base area, and the pressure in the separated recirculation area is lower than the surrounding atmospheric pressure. The separation at the blunt base will result in low pressure, resulting in a considerable amount of the base drag. In this work, the base pressure, which is lower than the ambient pressure leading to base drag, which is significant at the critical Mach numbers, is controlled by a passive control method such as a d-shaped rib. The duct diameter is 25 mm, and its length-to-diameter (L/D) ratio is 6. Ribs of heights ranging from 1 mm to 3 mm ribs were utilized to control the base pressure when located at L/D = 0.5, 1.0, 1.5, 2, and 3. When the rib was located at L/D = 1, the base pressure values for 3 mm rib height considerably increased the base pressure. The ribs with smaller heights are more vulnerable to changes in rib placements since the reattachment point is between L/D = 2 and 3D That results in slight variations in the base pressure ratios at other locations. According to the study, 2 mm ribs are the optimum option if the mission requires equating the base pressure to ambient atmospheric pressure. If the mission requires a fifty percent enhancement in base pressure, then even a 1 mm rib is sufficient. The 3 mm rib is the optimum option if the mission requirements call for raising the base pressure considerably.

Source: Results in Engineering

DOI: 10.1016/j.rineng.2025.105061

Authors: Mayur Bharatbhai Makwana, Sayed Ahmed Imran Bellary, Sher Afghan Khan, Abdul Aabid, Muneer Baig

Institutions: Ajeenkya DY Patil University, International Islamic University Malaysia, Prince Sultan University

Language: English

Topic: Computational Fluid Dynamics and Aerodynamics

Subfield: Computational Mechanics

Field: Engineering

Domain: Physical Sciences

Open Access status: gold

Estimated APC paid: $1,940

Funder: Prince Sultan University