Open Access

ARTICLE

Uncertainty Quantification of Dynamic Stall Aerodynamics for Large Mach Number Flow around Pitching Airfoils

Yizhe Han^1,2, Guangjing Huang¹, Fei Xiao¹, Zhiyin Huang^3,*, Yuting Dai¹

1 School of Aeronautic Science and Engineering, Beihang University, Beijing, 100191, China
2 Dongfang Turbine Co., Ltd., Dongfang Electric Corporation, Deyang, 618000, China
3 State Key Laboratory of Aerodynamics, Mianyang, 621000, China

* Corresponding Author: Zhiyin Huang. Email:

Fluid Dynamics & Materials Processing 2025, 21(7), 1657-1671. https://doi.org/10.32604/fdmp.2025.067528

Received 06 May 2025; Accepted 25 June 2025; Issue published 31 July 2025

Abstract

During high-speed forward flight, helicopter rotor blades operate across a wide range of Reynolds and Mach numbers. Under such conditions, their aerodynamic performance is significantly influenced by dynamic stall—a complex, unsteady flow phenomenon highly sensitive to inlet conditions such as Mach and Reynolds numbers. The key features of three-dimensional blade stall can be effectively represented by the dynamic stall behavior of a pitching airfoil. In this study, we conduct an uncertainty quantification analysis of dynamic stall aerodynamics in high-Mach-number flows over pitching airfoils, accounting for uncertainties in inlet parameters. A computational fluid dynamics (CFD) model based on the compressible unsteady Reynolds-averaged Navier–Stokes (URANS) equations, coupled with sliding mesh techniques, is developed to simulate the unsteady aerodynamic behavior and associated flow fields. To efficiently capture the aerodynamic responses while maintaining high accuracy, a multi-fidelity Co-Kriging surrogate model is constructed. This model integrates the precision of high-fidelity wind tunnel experiments with the computational efficiency of lower-fidelity URANS simulations. Its accuracy is validated through direct comparison with experimental data. Building upon this surrogate model, we employ interval analysis and the Sobol sensitivity method to quantify the uncertainty and parameter sensitivity of the unsteady aerodynamic forces resulting from inlet condition variability. Both the inlet Mach number and Reynolds number are treated as uncertain inputs, modeled using interval representations. Our results demonstrate that variations in Mach number contribute far more significantly to aerodynamic uncertainty than those in Reynolds number. Moreover, the presence of dynamic stall vortices markedly amplifies the aerodynamic sensitivity to Mach number fluctuations.

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Keywords

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