Evaluation of Transition Models for Laminar Flow Control Applications

Accurate prediction of laminar-to-turbulent transition is critical for the aerodynamic design of high-efficiency aircraft, especially those utilizing natural laminar flow (NLF) or hybrid laminar flow control (HLFC). This study evaluates transition models with a focus on linear stability theory (LST) and the $\gamma-Re_\theta$ transition model across two-dimensional (2D) and three-dimensional (3D) configurations. For 2D cases, low-fidelity solvers, such as panel and Euler methods using the $e^N$ method, are compared with Reynolds-Averaged Navier–Stokes (RANS) simulations employing the $\gamma-Re_\theta$ model. For 3D cases, the focus is on the CRM-NLF wing, where high-fidelity RANS simulations are used to evaluate transition behavior. Various turbulence and transition modeling strategies are assessed to determine their robustness, accuracy, and applicability to NLF-relevant flow conditions. Computational results—including pressure and skin friction distributions, transition locations, and lift and drag coefficients—are compared with available experimental data.