1 An Efficient Computational Approach for Hypersonic Nonequilibrium Radiation Utilizing Gaussian Quadrature and Space Partition J. S. Shang 1 , D.A. Andrienko 2 , G.P. Huang 3 , and S.T. Surzhikov 4 Wright State University Dayton, OH USA Institute for Problems in Mechanics Moscow, 119526 Federation of Russia Abstract An efficient computational capability for nonequilibrium radiation simulation via the ray tracing technique has been accomplished. The radiative rate equation is fully coupled with the aerodynamic conservation laws including chemical and chemical-physical kinetic models. The interdisciplinary governing equations are solved by an implicit delta formulation with the diminishing residual approach. The axisymmetric radiating flowfield over the reentry RAM-CII probe is simulated and verified with flight data and previous solutions by traditional methods. A one- order-of-magnitude computational efficiency improvement is derived from a space partition algorithm of the nearest neighbor search procedure for optical data interpolation from the nonequilibrium flowfield, and by local resolution refinement through the Gauss-Lobatto polynomial. Specifically, a computational efficiency improvement more than forty times is realized over that of existing simulation procedure. Nomenclature , , vi i c e Specific heat capacity at constant volume and internal energy, J/(mol∙K), J/mol , vm e Specific vibrational energy of m mode, J/kg F,G,H Flux vector functions  , b J  r Black body spectral intensity (Planck function), J/(s∙cm -1 ∙cm 2 ∙sr)   , J  r  Spectral intensity of heat radiation, J/(s∙cm -1 ∙cm 2 ∙sr)  Q  r Spectral emission source, J/(s∙cm -1 ∙cm 3 ∙sr) i L Cardinal function of Gauss quadrature, eq. (2-2) i M Molecular weight (kg Mole) , ij Q Internal energy source transfer, J/(s∙cm 3 ) r q Radiative heat transfer rate J/(s∙cm 2 ) , p  Pressure and density, J/m 3 , kg/m 3 t Time, s T Translational temperature, K (,, ) uuvw Velocity, m/s U Conservative dependent variables, ( , , ) u e   __________________________________________________________________________________________ 1 Research Professor, Mechanical and Materials Engineering Department. AIAA Fellow. 2 Ph.D. Candidates, Moscow Institute of Physics and Technology and Mechanical and Materials Engineering Department. AAA Student Member. 3 Chairman and Professor, Mechanical and Materials Engineering Department. AIAA Associate Fellow. 4 Professor, Deputy Director, Head of the Radiative Gasdynamic Laboratory, AIAA Associate Fellow. Downloaded by UNIVERSITY OF MICHIGAN on May 30, 2015 | http://arc.aiaa.org | DOI: 10.2514/6.2013-2587 21st AIAA Computational Fluid Dynamics Conference June 24-27, 2013, San Diego, CA AIAA 2013-2587 Copyright © 2013 by the American Institute of Aeronautics and Astronautics, Inc. The U.S. Government has a royalty-free license to exercise all rights under the copyright claimed herein for Governmental purposes. Fluid Dynamics and Co-located Conferences