No abstract

A nonequilibrium radiative heating prediction method has been used to evaluate several energy exchange models used in nonequilibrium computational uid dynamics methods. The radiative heating measurements from the FIRE II ight experiment supply an experimental benchmark against which di erent formulations for these exchange models can be judged. The models which predict the lowest radiative heating are found to give the best agreement with the ight data. Examination of the spectral distribution of radiation indicates that despite close agreement of the total radiation, many of the models examined predict excessive molecular radiation. It is suggested that a study of the nonequilibrium chemical kinetics may lead to a correction for this problem.

A method for predicting radiative heating and coupling e ects in nonequilibrium owelds has been developed. The method resolves atomic lines with a minimum number of spectral points, and treats molecular radiation using the smeared band approximation. To further minimize computational time, the calculation is performed on an optimized spectrum, which is computed for each o w condition to enhance spectral resolution. Additional time savings are obtained by performing the radiation calculation on a subgrid optimally selected for accuracy. Representative results from the new method are compared to previous work to demonstrate that the speedup does not cause a loss of accuracy and is su cient to make coupled solutions practical. The method is found to be a useful tool for studies of nonequilibrium ows. NomenclatureA ul transition probability sec Aerospace Engineer,

No abstract

No abstract