Solution accuracies of finite element reentry heat transfer and thermal stress analyses of space shuttle orbiter

Abstract

AbstractAccuracies of solutions (structural temperatures and thermal stresses) obtained from different finite element thermal and structural models set up for the space shuttle orbiter are compared and discussed. For studying the effect of element size on the solution accuracies of finite element heat transfer and thermal stress analyses of the orbiter, five structural performance and resizing (SPAR) thermal models and five NASA structural analysis (NASTRAN) structural models were set up for the orbiter wing midspan bay 3. The structural temperature distribution over the wing skin (lower and upper) surface of one bay was dome shaped and induced more severe thermal stresses in the chordwise direction than in the spanwise direction. The induced thermal stresses were extremely sensitive to slight variation in structural temperature distributions. Both internal convention and internal radiation were found to have equal effects on the orbiter structural temperatures. Minimum degrees of element fineness required for thermal and structural models for the orbiter to yield satisfactory solutions were established. In transient heat transfer analysis most of the computation time was consumed in the time‐dependent temperature calculations and not in the radiation view‐factor computations.