Analysis of coherent structures in dynamic stall via empirical mode decomposition and dynamic mode decomposition

Author(s)

Feitosa, Lucas ; Miotto, Renato ; Wolf, William

• Document type: Journal article
• Source: AIAA AVIATION 2023 FORUM; v. N/A, p. 12-pg., 2023-01-01.

Abstract

Large-eddy simulations of an SD7003 airfoil are conducted for an imposed plunging motion in order to induce a deep dynamic stall regime. Free stream flow parameters are set to Reynolds number Re= 60.000 and Mach number M = 0.1. Coherent structures are identified under the light of modal analysis via the multivariate empirical mode decomposition (EMD) and the multi resolution dynamic mode decomposition (mrDMD). The present study shows that the wavelet approach in the mrDMD does not fully compensate the errors in the frequency analysis related to rotational and translational invariances associated with vortex transport. Meanwhile the Hilbert-Huang transform applied to the intrinsic mode functions from EMD provides a more convenient way to identify the frequencies related to the coherent structures with negligible reconstruction error. (AU)

• FAPESP's process: 22/08567-9 - Numerical investigation of an airfoil under light dynamic stall
• Grantee: Lucas Feitosa de Souza
• Support Opportunities: Scholarships in Brazil - Master
• 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
• FAPESP's process: 21/06448-0 - High-fidelity numerical simulations applied in unsteady aerodynamics, turbulence and aeroacoustics
• Grantee: William Roberto Wolf
• Support Opportunities: Research Grants - Young Investigators Grants - Phase 2
• FAPESP's process: 22/09196-4 - Improving the understanding of unsteady aerodynamic flows via high-fidelity simulations, analytical modeling and deep learning techniques
• Grantee: Renato Fuzaro Miotto
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• 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