An investigation of compressibility effects on dynamic stall for a periodic plunging airfoil at moderate Reynolds number

Author(s)

Miotto, Renato ; Wolf, William ; Gaitonde, Datta ; Visbal, Miguel

• Document type: Journal article
• Source: AIAA SCITECH 2021 FORUM; v. N/A, p. 10-pg., 2021-01-01.

Abstract

The effects of compressibility on the onset of the dynamic stall vortex (DSV) over a wing section are analyzed by means of large eddy simulations. A SD7003 airfoil is considered at two different freestream Mach numbers, being M-infinity = 0.1 and 0.4, and at a chord-based Reynolds numbers of Re-c = 6 x 10(4). The profile undergoes a periodic plunging motion. Results show that compressibility causes the DSV to form further downstream the leading edge. Moreover, higher compressibility also leads to weaker DSVs with lower residency time. For the current flow configuration and airfoil kinematics, the mechanisms of dynamic stall onset involve the upstream propagation of Kelvin-Helmholtz instabilities that trigger separation of a shear layer formed at the leading edge. In order to better characterize the onset of the DSV, two empirical criteria are assessed for the cases investigated: the leading edge suction parameter and the chord normal shear layer height. The application of both criteria show that the leading edge suction parameter is highly dependent on compressibility. (AU)

• FAPESP's process: 13/07375-0 - CeMEAI - Center for Mathematical Sciences Applied to Industry
• Grantee: Francisco Louzada Neto
• Support Opportunities: Research Grants - Research, Innovation and Dissemination Centers - RIDC
• FAPESP's process: 17/10795-1 - Investigation of Turbulent Compressible Flows Past Airfoils Using High-Fidelity Simulations
• Grantee: Renato Fuzaro Miotto
• Support Opportunities: Scholarships in Brazil - Doctorate
• FAPESP's process: 19/02335-6 - Investigation of the flow physics of airfoils under dynamic stall using large eddy simulations and post-processing techniques
• Grantee: Renato Fuzaro Miotto
• Support Opportunities: Scholarships abroad - Research Internship - Doctorate
• FAPESP's process: 13/08293-7 - CCES - Center for Computational Engineering and Sciences
• Grantee: Munir Salomao Skaf
• Support Opportunities: Research Grants - Research, Innovation and Dissemination Centers - RIDC