In establishing the mathematical model and performing computer simulation of the operation of the gel propulsion system, it was assumed that the diaphragm valve and the electric detonation valve are opened at the beginning and that the gel propellant had already filled the main pipeline of the supply system (including the catheter, the reducing catheter, the orifice catheter, filter, flow regulator, etc.). After the electric gas valve or solenoid valve is energized and opened, the gel propellant starts to fill the liquid collection chamber, capillary tube, nozzle, etc. After the propellant is added, it enters the decomposition chamber to undergo atomization, evaporation, catalysis, and decomposition to generate high-temperature and high-pressure gas. Then, the gas is accelerated in the nozzle and is ejected at high speed from the nozzle to generate thrust.