The Pressure Analyzing of the C-D Rocket Nozzle Considering Isentropic Flow Theory

Abstract

This study investigates the pressure analysis of the Convergent-Divergent (C-D) rocket nozzle according to isentropic flow theory. For this purpose, the rocket nozzle flow is assumed to be isentropic and adiabatic. On the other hand, the flow is considered one-dimensional, compressible, and continuous flow. Firstly, the equations for the one-dimensional isentropic flow model are formulated. Then, these formulations are adapted to the C-D rocket nozzle presented in this study, considering the rocket's convergent, throat, and divergent sections. The equations of the physical models are simulated with MATLAB and Simulink combined algorithm with numerical solver. The parameters mass flow rate ((m) ) ̇, chamber pressure (Pc), chamber temperature (Tc), specific heat ratio ( k ), specific gas constant (R), and Mach number ( Ma ) are used to verify the presented algorithm. The output values obtained from these input parameters are compared to the literature study given in the study. The results obtained from the verification study indicate the presented model is in agreement with the literature studies by %99.26 sensitivity ratio. Finally, the temperature change for the five different input chamber pressures (Pc= 25, 150, 275, 400, and 500 bar) in the C-D rocket nozzle is presented according to mode number.