Numerical Simulation of Chemically Reacting High-Enthalpy Flows

This work is relevant to numerical simulation of atmospheric entry phase of space missions and in high enthalpy facilities producting flow conditions close to flight conditions. Such flows are featured by low pressure and high temperature, which induces thermal and chemical nonequilibrium, while calculations with equilibrium assumption give both qualitative and quantitative errors.

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Assessment of Heat Flux Prediction Capabilities of Residual Distribution Method: Application to Atmospheric Entry Problems

Communications in Computational Physics ◽

10.4208/cicp.070414.211114a ◽

2015 ◽

Vol 17 (3) ◽

pp. 682-702 ◽

Cited By ~ 9

Author(s):

Jesús Garicano Mena ◽

Raffaele Pepe ◽

Andrea Lani ◽

Herman Deconinck

Keyword(s):

Heat Flux ◽

Numerical Technique ◽

Ideal Gas ◽

Residual Distribution ◽

Present Contribution ◽

Distribution Method ◽

High Enthalpy ◽

Straightforward Application ◽

Blunt Bodies ◽

Chemically Reacting

AbstractIn the present contribution we evaluate the heat flux prediction capabilities of second-order accurate Residual Distribution (RD) methods in the context of atmospheric (re-)entry problems around blunt bodies. Our departing point is the computation of subsonic air flows (with air modeled either as an inert ideal gas or as chemically reacting and possibly out of thermal equilibrium gas mixture) around probe-like geometries, as those typically employed into high enthalpy wind tunnels. We confirm the agreement between the solutions obtained with the RD method and the solutions computed with other Finite Volume (FV) based codes.However, a straightforward application of the same numerical technique to hypersonic cases involving strong shocks exhibits severe deficiencies even on a geometry as simple as a 2D cylinder. In an attempt to mitigate this problem, we derive new variants of RD schemes. A comparison of these alternative strategies against established ones allows us to derive a diagnose for the shortcomings observed in the traditional RD schemes.

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Study of Thermo-Chemical Non-Equilibrium Phenomena behind Strong Shock Waves at Atmospheric Reentry

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.274.13 ◽

2011 ◽

Vol 274 ◽

pp. 13-22 ◽

Cited By ~ 1

Author(s):

R. Allouche ◽

R. Haoui ◽

J.D. Parisse ◽

R. Renane

Keyword(s):

Numerical Simulation ◽

Equilibrium State ◽

Chemical Species ◽

Strong Shock ◽

One Dimensional ◽

Atmospheric Reentry ◽

High Enthalpy ◽

Finite Differences Method ◽

Strong Shock Waves ◽

Non Equilibrium

This work consists of the numerical simulation of high enthalpy flows. The numerical model is governed by Euler equations and supplemented by the equations of the chemical kinetics modeling the phenomena of the chemical air components in a non-equilibrium state. The finite differences method is used for numerical simulations, the phenomena of a hypersonic flow one-dimensional reactive, non-viscous, chemical non-equilibrium is developed taking into account the physicochemical phenomena like the vibration, the dissociation of the diatomic molecules, the ionization of molecules and the formed atoms of chemical species to higher temperatures which appear behind a strong shock detached and evolve according to time in a relaxation range until to reach the equilibrium state. We are interesting in particular on the temperature effect in ionization of the atoms and the molecules.

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