Temperature Histories in Ceramic-Insulated Heat-Sink Nozzle

Temperature histories were calculated for a composite nozzle wall by a simplified numerical integration calculation procedure. These calculations indicated that there is a unique ratio of insulation and metal heat-sink thickness that will minimize total wall thickness for a given operating condition and required running time. The optimum insulation and metal thickness will vary throughout the nozzle as a result of the variation in heat-transfer rate. The use of low chamber pressure results in a significant increase in the maximum running time of a given weight nozzle. Experimentally measured wall temperatures were lower than those calculated. This was due in part to the assumption of one-dimensional or slab heat flow in the calculation procedure.