Capturing transition around low-Reynolds number hydrofoil with zero-equation transition model

Abstract

Compared with the local correlation-based shear stress transport ( SST) [Formula: see text] transition model (where SST [Formula: see text] transport equations are coupled with intermittency [Formula: see text] and transitional momentum-thickness Reynolds number [Formula: see text] transport equations), relatively simple and convenient modifications are applied to the parent SST [Formula: see text] model for computing natural and separation-induced transitions over the hydrofoil at a low-Reynolds number ( LRN). The curiosity toward hydrofoil performance at an LRN has been enhanced by increasing attention to autonomous marine systems, deserving numerical simulations for transitional flow using computational fluid dynamics. With the newly devised transitional SST (T-SST) model, the viscous sublayer blending function [Formula: see text] is slightly modified, and a stress-intensity parameter as a function of eddy-to-laminar viscosity ratio [Formula: see text] is introduced; intended formulations are plausible and have significant impacts on the transition prediction. Owing to the inherent potential for predicting bypass transition, two anisotropic versions of the [Formula: see text]( V2F) turbulence model are selected to evaluate their competencies in capturing separation-induced and natural transitions. Results demonstrate that natural transition prediction is more challenging than separation-induced transition for the V2F model. Nonetheless, the T-SST model performs consistently well in replicating both transitional phenomena.