BALLISTIC HEATING OF PROPELLING GAS IN A SHOCK-TUBE WITH A FREE-MOVING PISTON

An efficient method is treated of increasing the internal energy of pr opelling gas in a shock tube by way of its nonisentropic compression b y a free piston in a ballistic driver. The internal ballistics of the system during the piston motion in the barrel, divided into two sectio ns by an additional perforated diaphragm, are investigated theoretical ly. It is shown that throttling of preheated gas through the diaphragm hole makes it possible to reduce the heat losses in the course of com pression and raise the efficiency of ballistic driver by a factor of m ore than two.