%0 Journal Article %A Martin, Heath T. %A Houim, Ryan W. %A Degges, Matthew J. %A Zhang, Baoqi %A Kuo, Kenneth K. %D 2014 %I Begell House %K heat flux measurement, inverse heat conduction, solid rocket motor, ablative materials, ablation %N 2 %P 169-191 %R 10.1615/IntJEnergeticMaterialsChemProp.2014008148 %T DETERMINATION OF TOTAL SURFACE HEAT FLUX TO ABLATIVE INTERNAL INSULATORS IN SOLID ROCKET MOTORS VIA INVERSE HEAT CONDUCTION ANALYSIS %U https://www.dl.begellhouse.com/journals/17bbb47e377ce023,0e9dc45e19b62aca,288585984b0f72a3.html %V 13 %X In assessing the performance of ablative internal insulators in solid rocket motors (SRMs), it is useful to measure the total surface heat flux incident on the insulators. The simplicity of this proposition, however, belies the challenges involved in performing such a measurement. Any device installed in an SRM is subjected to both high temperatures and heating rates; therefore, one challenge is the selection of a gauge material that can not only survive this environment intact, but also deliver accurate and reliable measurements while exposed to these harsh conditions. A second, and more problematic, difficulty is that of introducing the gauge into the SRM environment in a manner that is minimally invasive and will yield results that are an accurate representation of that environment. In this study, a total heat flux gauge using graphite as the sensor material was designed, fabricated, and tested. Multiple micro-thermocouples were embedded at different depths in the graphite sensor, and their recorded temperature histories were utilized in an inverse heat conduction analysis to deduce the total heat flux to and instantaneous temperature of the sensor surface. The gauge was employed in six subscale SRM firings performed for a study of ablative internal insulation. This heat-flux measurement technique proved to be both robust, producing useful results for 9 of 11 total installations, and accurate, with total uncertainty as calculated from quantifiable elemental uncertainties being no greater than 7% of the deduced flux. %8 2014-05-15