The flow characteristics of asymmetric vortices and the side force of a tangent-ogive-cylinder flight vehicle at high angles of attack have been studied by using a three-dimensional upwind Navier-Stokes method with the k-! turbulence model and a simple laminar-turbulent transition model. Various patterns of asymmetric vortices and side forces are studied by using various asymmetric laminar-turbulent transition conditions. Asymmetrically changing turbulent viscosities that arise from asymmetric laminar-turbulent transition conditions cause asymmetric crossflow vortex structures and side forces at higher angles of attack. The magnitude and structure of the crossflow vortices and side forces were sensitive to changes in the factors of the model of laminar-turbulent transition. Nomenclature= cylinder diameter L n = length of the nose part Ma = Mach number q = freestream dynamic pressure R = cylinder radius Re D = Reynolds number, UD= x = axial distance from the nose tip = angle of attack = kinematic viscosity T = turbulent viscosity in the fully turbulent region TR = turbulent viscosity in the transition region

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The flow characteristics on a supersonic inlet with bleeding system at various angles of attack are studied by using computational 3D turbulent flow analysis. A turbulent CSCM compressible upwind flux difference splitting Navier-Stokes method with k-w turbulence model is used to compute the inlet flowfields. MPICH-2.0 library and PC-cluster system are used to reduce computational times. Distortion and average of total pressure recovery at the AIP (aerodynamic interface plane) are used as evaluation criteria of inlet performance. The flow characteristics at zero of angle of attack of double-cone type supersonic inlet without and with bleeding system have been compared. Without bleeding system inlet with the strong SBLI (shock/boundary-layer interaction) induces slow flow recovery near the throat and produces very thick boundary layer downstream. But the bleeding system successfully removes the low energy flow from the boundary layer near the throat. As the angle of attack at the AIP because large, we can see more non-uniform flow field, and the non-uniform flow field is the major aggravating factor of inlet performance.