عنوان مقاله [English]
The rocket design with low motor weight and more power paves the way for researchers to develop innovations in rocket engines. Combined propulsion design focuses on the simultaneous combustion of solid and liquid propellant components in the combustion chamber. In the present work, simultaneous combustion modeling of propellants (solid and liquid) was done. By writing house code and applying simplifying assumptions, the propulsion system behavior was analyzed. Different compositions were considered for systems with 250, 500, 750, and 1000 kg total mass of propellants. It shows by increasing the solid propellant percentage to 60%, "the maximum thrust" was reached its maximum value while decreasing the motor combustion time. When the solid propellant percentage increases, "total impulse" increases accordingly, and the specific impulse decreases. In another comparison, for a propellant combination with 150 kg of the solid propellant charge and 100 kg of liquid propellant charge, the injection rate related to liquid propellant was adjusted at 4, 8, and 16 liters per second. The results show by increasing injection rate, maximum thrust increased, and total impulse decreased. The "specific impulse" was almost constant.