ANALYSIS OF GALILEO PROBE HEATSHIELD ABLATION AND TEMPERATURE DATA

The Galileo Probe deceleration module contained instrumentation to measure heatshield ablation and temperatures during its hypersonic entry into the atmosphere of Jupiter. The ablation data reduction and analysis were reported previously; therefore, only a brief review is provided. One-dimensional transient analyses of the heatshield ablation, pyrolysis, and heat conduction were performed at the thermometer locations. These calculations were coupled with an axisymmetric heat conduction model to predict the thermometer temperature response. Near the end of the frustum, the temperature and recession data are very consistent. The measured recession is 3.63 § 0.15 cm, and the estimated peak heat  ux and heat load are 13.4 § 0.5 kW/cm2 and 161 § 6 kJ/cm2, respectively. At the aft cover, the material response analyses do not match the low magnitude and slope of the temperature data, which seem to indicate that heat conduction into the heatshield was lower than expected.