PYROSTATIC TESTS OF JA-2 TYPE POWDER

Abstract

Literature data concerning ballistic properties of JA-2 powders was studied. The data was compared with results of own tests received for powder LO5460 manufactured by Nitrochemie AG. Pyrostatic tests were carried out in the manometric chamber having the volume of 200 cm3. The force of the powder and the co-volume of powder gases were measured. The influence of thermal losses into these parameters was evaluated by using a methodology proposed by the authors. Exponent value in the powder burning law and curves of dynamical liveliness of the powder were established. The curves actually overlap what shows the adequacy of the physical law of burning. It was proved that the ignition of tested powder takes place prior the complete burning of an igniting charge. It was taken into account at modification of the method for establishing the dynamic liveliness. Exploiting results of measurements for powder grains geometry and the curves of dynamical liveliness a coefficient of linear burning velocity was established. A good compliance with literature data was achieved for the dependence of linear burning rate on the pressure. It was proved that the geometrical burning law is adequate with the description of tested powder burning for changes of relative volume of burned powder above 0.2.