Thermodynamic Properties of Nitryl Chloride
The calorimetric heat of formation of gaseous nitryl chloride from the elements at 25° has been found from the heat of the reaction of gaseous nitryl chloride with nitric oxide as confirmed by the heat of the reaction between nitrosyl chloride and nitrogen pentoxide. The value is +3.12±0.16 kcal/mole (endothermic). From the equilibrium constants for the reactions 2NO2+Cl2=2ClNO2 and NO2+ClNO=NO+ClNO2 the entropy of nitryl chloride at 25° has been found to be 65.46±0.6 eu.
The correction of a thermal model for a thermally controlled satellite in ground test conditions is studied using a Monte Carlo hybrid algorithm. First, the global and local parameters are summarized according to sensitivity analyses on uncertain parameters, and then the model correction is treated as a parameter optimization problem to be solved with a hybrid algorithm. Finally, the correction of the thermal model is completed using a layered correction method. The sensitivity analysis showed that the effective emissivities across the multi-layer insulation (MLI) and the emissivities of the thermal control coating are global parameters, while the contact heat transfer coefficients are local parameters. After correction, the deviations between the calculated and test values were all within ±3°C. The final results prove that the method in this study is superior to traditional methods and satisfies the requirements for thermal model correction.