Investigation on hydrodynamic characteristics of a hydrofoil based on γ-Re_θt transition model

Abstract

The complex flow field caused by the dynamic stall can affect the operational stability of hydrodynamic machinery. In this paper, the NACA0009 blunt trailing edge hydrofoil is used as the object of study, and the dynamic stall characteristics of the hydrofoil are investigated by using the transition model and the dynamic mesh method. It is found that the hydrofoil deep stall calculated by the transition model is delayed compared to that calculated without the transition model. The hydrofoil dynamic stall can be divided into four stages, initial stage, development stage, stall inception stage and deep stall stage. In the initial stage and the development stage, the lift and drag characteristics are influenced by the shedding vortex. In the stall inception stage and the deep stall stage, the lift and drag characteristics are influenced by the leading edge separation vortex and the trailing edge vortex. The increase of angular velocity and Reynolds number of the dynamic hydrofoil delay the onset of the deep stall while accelerating the boundary layer transition. The research in this paper has a certain guiding effect for the safe and stable operation of hydrodynamic machinery.

Investigation on stall characteristics of marine centrifugal pump considering transition effect

“…The γ-Re θt transition model proposed by Menter (Menter et al, 2004), is the most used in simulations, which consists of the Re θt (transition momentum thickness Reynolds number) transport equation and the γ (intermittent factor) transport equation. Ye (Ye et al, 2021(Ye et al, , 2022, Delafin (Delafin et al, 2014), Zeng (Zeng et al, 2021) and Zhang (Zhang et al, 2019) obtained hydrodynamic properties of the hydrofoil by using the model. The γ transition model (Menter et al, 2015) and algebraic transition model (Menter et al, 2022) proposed by Menter also work very well for engineering problems, but the model show a stronger sensitivity to mesh resolution in streamwise direction.…”