Numerical analysis of hypersonic continuum and rarefied gas flows near blunt probes is presented under conditions of intensive gas blowing from the surface. Nonequilibrium parameters in the multicomponent flows were evaluated for slot and uniform injections of air, helium, and hydrogen. Numerical results indicate that the most effective cooling of the probe surface occurs at moderate uniform in...

LA-UR-08-1690 30 Associate Directorate for Theory, Simulation, and Computation (ADTSC) LA-UR-09-01756 Understanding the nature of compressible turbulence is of fundamental importance in many applications ranging from astrophysics to combustion and aerospace engineering. Highly compressible turbulence is now thought to control star formation in dense molecular clouds [1]. The ability to paramete...

Most of numerical methods for deterministic simulations of rarefied gas flows use the discrete velocity (or discrete ordinate) approximation. In this approach, the kinetic equation is approximated with a global velocity grid. The grid must be large and fine enough to capture all the distribution functions, which is very expensive for high speed flows (like in hypersonic aerodynamics). In this a...

This paper reviews the most dependable heat flux sensors, which can be used with InfraRed (IR) thermography to measure convective heat transfer coefficient distributions, and some of their applications performed by the authors' research group at the University of Naples Federico II. After recalling the basic principles that make IR thermography work, the various heat flux sensors to be used wit...

A novel numerical flux for the Euler equations which is consistent for kinetic energy and entropy condition was proposed recently [1]. This flux makes use of entropy variable based matrix dissipation which can be shown to satisfy an entropy inequality. For hypersonic flows a blended scheme is proposed which gives carbuncle free solutions for blunt body flows while still giving accurate resoluti...

The applicability of three numerical approximation methods of solving the Navier-Stokes equations (local stagnation streamline approximation, ‘parabolized’ equations, and the thin-viscous-shock-layer approach) have been analyzed to study nonequilibrium hypersonic viscous flows near blunt bodies. These approximations allow reducing the calculation time by factor of 10 in comparison with the time...

In this paper we incorporate a low magnetic Reynolds number MHD model to a high order CFD algorithm with WENO and a low diffusion scheme for 3D Navier-Stokes equations. We present results for hypersonic laminar flows around a flat plate and around a blunt body, with different strengths of magnetic fields, to demonstrate the methodology. More simulations, including turbulence, are in progress an...