Estimation of shock-induced buffet onset

A steady Navier-Stokes flow solver has been applied to estimate the shock-i nduced buffet onset boundary with the underlying assumption that a basicall y unsteady flow will remain unsteady in its nature and that the use of acce leration scheme will not change this basic nature. The main aim of these co mputations is to use the present steady, accelerated Navier-Stokes solver t o make an engineering estimate of the buffet onset of an airfoil. The buffe t onset boundary for NACA 0012 appears to have been estimated well and it i s seen to be in good agreement with the experimental data. No claim of time -accurate feature is made in these computations and what is presented here is purely an engineering method to estimate "whether shock buffet onset has begun or not" which is a significant help in the preliminary aerodynamic d esign phase of the aircraft. Use of a highly accelerated code makes these o therwise time-consuming estimates extremely efficient and economical.