A preliminary hybrid particle-continuum computational framework for simulating hypersonic interacting flows is proposed. The framework consists of the direct simulation Monte Carlo-Information Preservation (DSMC-IP) method coupled with a Navier-Stokes solver. Since the DSMC-IP method provides the macroscopic information in each time step, determination of the continuum fluxes across the interfa...

5.1 ABSTRACT Supersonic combustion data obtained at the low static temperatures appropriate for an efficient scramjet engine are reviewed. Attention is directed at the methods by which the fuel was ignited and combustion maintained. The cited supersonic combustion experiments are grouped under the six headings: chemical intiators; non-uniform flows; turbulent flameholding; combustion induced co...

Experimental heat flux measurements are made using both thermocouple and thin film gages in high-temperature, hypersonic flows. Thermocouple and thin film gages have individually been extensively used in relatively high and low enthalpy conditions respectively. In this study, three test conditions with varying (intermediate) stagnation enthalpies, Mach and Reynolds numbers are created in an exp...

Presence of plasma turbulence can strongly influence propagation properties of electromagnetic signals used for surveillance and communication. In particular, we are interested in the generation of low frequency plasma turbulence in the form of coherent vortex structures coexisting with short scale density irregularities and of lower hybrid turbulence. Lower-hybrid type density irregularities a...

In the present work, we propose a reformulation of the fluxes and interpolation calculations in the PISO method, a well-known pressure-correction solver. This new reformulation introduces the AUSM up flux definition as a replacement for the standard Rhie and Chow method of obtaining fluxes and central interpolation of pressure at the control volume faces. This algorithm tries to compatibilize t...

A direct numerical simulation ~DNS! database is used to develop a model of subgrid-scale temperature fluctuations for use in large-eddy simulations of turbulent, reacting hypersonic flows. The proposed model uses a probability density representation of the temperature fluctuations. The DNS database reveals a physically consistent relation between the resolved-scale flow conditions that may be u...

Hypersonic flows of nitrogen, oxygen, argon, and carbon dioxide near a toroidal ballute have been investigated numerically using the Direct Simulation Monte-Carlo technique under transition rarefied-gas flow conditions (Knudsen numbers from 0.005 to 10). Strong influences of the geometrical factor (a ratio of the distance between the axis of symmetry and the torus disk center, and the torus rad...

Current challenges and problems pertaining to the development and application of the DSMC method for high-altitude aerodynamics are discussed. Attention is paid to issues related to the efficiency and accuracy of the method in the near-continuum regime, as well as its use for modeling of rarefied flows with real gas effects. Accurate prediction of force and heat aerodynamic characteristics of r...

We present a new numerical code, PLUTO, for the solution of hypersonic flows in 1, 2 and 3 spatial dimensions and different systems of coordinates. The code provides a multi-physics, multi-algorithm modular environment particularly oriented towards the treatment of astrophysical flows in presence of discontinuities. Different hydrodynamic modules and algorithms may be independently selected to ...

A one-dimensional material response implicit solver with surface ablation and pyrolysis is implicitly coupled to LeMANS, a CFD code for the simulation of weakly ionized hypersonic flows in thermo-chemical non-equilibrium. Following verification and validation of the blowing wall boundary conditions and ablation coupling, the implementation of a moving mesh algorithm in the flow solver is propos...