Calculation Of Steady And Unsteady Airfoil Flow Fields Via The Navier Stokes Equations PDF Download

The unsteady, compressible, Reynolds-averaged Navier-Stokes equations were solved for the flow field about an external compression axi-symmetric inlet with a length to diameter ratio, L/D = 15.88, at Mach 2.0 and a Reynolds number based on diameter, ReD = 2.36 times 10 to the 6th power, operating in the near-critical and subcritical flow regimes. The near-critical solution reached a stable steady state while the subcritical solutions attained an unstable bounded oscillatory state, characterized by large amplitude pressure oscillations and traveling shock waves. This phenomenon is a result of a shear layer instability combined with a closed-loop feedback of reflected disturbances and the naturally occurring self-sustained oscillations are commonly known as buzz. Numerical results are given in terms of Mach contours, velocity field plots, pressure-time traces at selected stations, as well as mass flux and other mass-averaged quantities along the duct length. Comparison with experiment is also given. (Author).