Pressure loading, ignition phase

During the ignition phase, as the pressure increases, the propellant is loaded by hydrostatic pressure imposed on a biaxial tensile stress field. Because the propellant is incompressible in the ignition condition, the pressure is transmitted entirely to the case, which, being thin because of the weight requirement, presents significant hoop deformations. Therefore, a tensile strain... 

Safety tests were also made on 0.2 cu. foot (over 5 liters) of silica gel loaded with ozone. The main conclusion from these tests was that, at loadings up to 10 pounds of ozone per 100 pounds of gel, if the temperature is kept below —78° C. so that the vapor pressure of the ozone in the gas phase of the vessel is low, an explosion will not take place when a hot wire buried in the gel is ignited. At higher temperatures explosions, apparently initiated in the gas phase, took place, but their force was greatly damped by the presence of the gel. 

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