Effect of Height on the Supersonic Flow over a Blunt Vertical Fin

Abstract

Understanding how protrusions, such as fins attached to flat or streamlined bodies, affect aerodynamics, especially in high-speed contexts, is vital for aerospace applications. These protrusions significantly influence overall aerodynamics and require a comprehensive understanding for accurate analysis and prediction of aerodynamic performance. This understanding is particularly critical in supersonic flight, where even minor aerodynamic disturbances can impact vehicle stability and efficiency. Therefore, a thorough understanding of protrusion-induced flow phenomena is essential for advancing aerospace engineering and improving supersonic vehicle performance and safety. The present paper focuses on the complex supersonic flow over a vertical fin, using a combination of experimental and computational methods. The study aims to understand how variations in fin height influence the behavior of the Lambda shock and any resulting changes in shock length. Specifically, the paper investigates different fin height-to-diameter (H/D) ratios ranging from 0.5 to 1.5 in steps of 0.25. To achieve this, both experimental testing in a supersonic wind tunnel and numerical simulations using the commercial CFD tool ANSYS-FLUENT are employed. Through this dual approach, the paper seeks insights into the characteristics of the Lambda shock and its effects on key aerodynamic parameters, such as shock strength and drag coefficient. By thoroughly investigating these aspects, the paper contributes to a deeper understanding of the complex flow phenomena associated with supersonic flow over vertical fins, potentially guiding the design and optimization of aerospace vehicles. The outcomes indicate that a fin height of 12 mm (H/D=1.0) provides the best balance in terms of pressure distribution, Lambda shock length, and drag coefficient, making it the optimal choice for enhancing aerodynamic stability and performance in supersonic conditions.

Keywords

• protrusions
• vertical fin
• aerodynamics
• experimental testing, supersonic flow
• aerospace applications
• flow-phenomena