Numerical Examination on Two-Equations Turbulence Models for Flow Across NACA 0012 Airfoil with Different Angle of Attack

Abstract

Selection of an appropriate and efficient turbulence models is important for fast and

accurate computation in fluid dynamics. In order to investigate the computational

efficiency of turbulence models, numerical examination based on two-equations

turbulence models for flow across NACA 0012 airfoil was carried out by using ANSYS

Fluent at various angle of attack (-12o to 20o ) and at a Reynold number of 3 × 106 . The

case study is chosen as its transition from viscid to inviscid flow region which would

put a strain on computational performance of turbulence models. The two-equation

models being investigated are Standard k-ε model, RNG k-ε model, k-ε Realizable

model, Standard k-ω model, k-ω BSL model and k-ω SST model. The drag, lift and

pressure coefficient between simulation and experimental results are compared. The

convergence rate of these turbulence models is collated as well. The contours of static

pressure and velocity magnitude was simulated, and boundary layer separation was

noticed from 10° angle of attack. In general, the predicted data have good agreement

with experimental data. Amongst the investigated models, k- SST model showed the

best agreement with experimental result meanwhile RNG k-ε model showed the

slowest convergence rate among all the turbulence models.