An improved Navier-Stokes flow computation of AGARD case-10 flow over RAE2822 airfoil using Baldwin-Lomax model

摘要

Transonic flow over the RAE2822 airfoil has been solved for flow coditions corresponding to the AGARD test case 10. An extensively tested steady Navier-Stokes flow solver based on the finitevolume cell-centered explicit Runge-Kutta time stepping scheme has been used to simulate the flow. The experiment has shown a zone of separated flow after the foot of the shock. Under the conditions of considerable shock-boundary layer interaction, the Baldwin-Lomax eddy viscosity model has been found to produce unsatisfactory results. But, at the same time, efforts using different schemes and the turbulence/eddy viscosity models do not seem to lead to any significantly improved simulation of this flow even when computations have been made with marginally adjusted mach number and/or angle of attack. Interestingly, when the present code was used to study the above case, significantly improved result has been obtained (with marginally adjustedM ∞ and α) that is as good as and even better than the computations seen in the literature using various improved turbulence models. This computation appears to be the first of its kind where Baldwin-Lomax model has been used to produce such good quality result for this flow. This may even point towards a need to have another look at the wind tunnel interference correction used in AGARD test.