Sustainable Marine Structures

Numerical Simulations of the Pitching Airfoil by Using Discrete Vortex Method

Peng Ren

Department of Engineering Mechanics, School of Naval Architecture, Ocean and Civil Engineering, Shanghai Jiao Tong University, Shanghai, 200030, China; Key laboratory of Hydrodynamics (Ministry of Education), Shanghai Jiao Tong University, Shanghai, 200030, China

Ke Lin

Department of Engineering Mechanics, School of Naval Architecture, Ocean and Civil Engineering, Shanghai Jiao Tong University, Shanghai, 200030, China; Key laboratory of Hydrodynamics (Ministry of Education), Shanghai Jiao Tong University, Shanghai, 200030, China

Jiasong Wang

Department of Engineering Mechanics, School of Naval Architecture, Ocean and Civil Engineering, Shanghai Jiao Tong University, Shanghai, 200030, China; Key Laboratory of Hydrodynamics (Ministry of Education), Shanghai Jiao Tong University, Shanghai, 200030, China; SJTU-Sanya Yazhou Bay Institute of Deepsea Science and Technology, Sanya, Hainan, 572024, China

DOI: https://doi.org/10.36956/sms.v5i2.944

Received: 5 September 2023; Revised: 15 October 2023; Accepted: 25 October 2023; Published: 31 October 2023

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Abstract

This paper presents a two-dimensional discrete vortex method that uses the vortex growing core model to simulate the unsteady force and the wake patterns of the pure pitching airfoil efficiently and accurately. To avoid the random fluctuation caused by the random walk method, a vortex growing core method is used to simulate the viscous diffusion motion. In addition, the vortices fall off randomly on the body surface. Referring to the experimental configurations of Mackowski and Williamson (2015), a good agreement is achieved through the comparisons between the present simulation results and the experimental results, including the mean force coefficients, oscillation amplitude and wake patterns. It shows that the two-dimensional discrete vortex method can be used to predict the mechanical behavior and wake patterns on the pitching airfoil motion.

Keywords: Discrete vortex method, Pitching motion, Airfoil, Thrust

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