Dynamic Model of Launching Process for Novel Gas Gun and its Validation

Launching process of gas gun involves valve opening, gas flowing, and bullet moving, etc, which is complex and difficult to describe clearly, and establishing an accurate dynamic model of the process is meaningful to gas gun design and analysis. The dynamic model of launching process for a novel gas gun is originally posted in this paper, which is described with a series of equations according to mass conservation equations, gas equation of state, Newton’s second law, relationship of movement and space. And the key parameters such as muzzle velocity, gas pressure, and time taken to open valve are calculated based on the dynamic model above-mentioned. Then, the bullet launching experiment was designed and implemented, and muzzle velocity of the bullet was measured. The deviation of the muzzle velocity calculated based on the dynamic model and the velocity measured in the experiment is less than 3 percents, which shows that the dynamic model established could describe the launching process of the gas gun accurately.