Computational analysis of turbulent flow around a NACA0012 airfoil at low Reynolds numbers using a two-fluid model

Abstract

This paper presents a detailed numerical investigation of the turbulent flow structure around a NACA0012 airfoil at low Reynolds numbers using a two-fluid turbulence model implemented in the COMSOL Multiphysics environment. The study focuses on Reynolds numbers ranging from 10,000 to 30,000 at an angle of attack of α = 0°, and from 10,000 to 25,000 at α = 5°. The primary objective is to assess the capability of the two-fluid model in accurately capturing the flow separation, wake development, and turbulent stress distribution in the low-Reynolds-number regime. The obtained numerical results are systematically compared with those from the widely used Menter’s SST (Shear Stress Transport) model and available experimental data from literature to validate the accuracy and robustness of the proposed approach. The simulations demonstrate that the two-fluid turbulence model provides improved agreement with experimental measurements, particularly in predicting the velocity profiles and Reynolds stress distributions in the near-wake region. The implementation of the model within the COMSOL Multiphysics framework shows high numerical stability, reliable convergence, and computational efficiency across all tested flow regimes. Furthermore, the two-fluid model exhibits enhanced capability in describing complex anisotropic turbulence effects that are often underrepresented in traditional RANS-based models. The outcomes of this study confirm that the two-fluid turbulence model is a promising and accurate alternative for analyzing low-Reynolds-number aerodynamics, offering valuable insights for the design and optimization of small-scale air vehicles, micro air vehicles (MAVs), and other low-speed aerodynamic systems.