Cool Propellants: Flame Temperatures and Force Constants: New Calculations Taking into Account the Formation of Methane and Ammonia.

摘要

Calculations of the flame temperatures and force constants of certain 'cool' gun propellants have been carried out, taking into account the formation of methane and ammonia. It has been shown that for propellants F.527/155 and F.428/180 the 'true' flame temperatures are 2045 degrees K. and 2050 degrees K. compared with the 'nominal' values of 1942 degrees K. and 1950 degrees K. obtained by neglecting the formation of those gases. the 'true' force constants are respectively 1493 and 1453 inch-tons/lb.. compared with 1474 and 1436 inch-tons/lb. In the vase of the propellants F.527/156 and F.428/181 having a 'nominal' flame temperature of 1700 degrees K, the true flame temperatures are 1905 and 1915 degrees K, respectively and the corresponding force constants nearly 5 per cent, above those obtained by neglecting the formation of methane and ammonia. Conditions for the deposition of carbon do not exist for any of those propellent under conditions of maximum pressure but in the case of F.428/180 and F.428/181 conditions are such that carbon deposition could occur if equilibrium were attained at the moment of shot ejection.