Eventos Anais de eventos
COBEM 2021
26th International Congress of Mechanical Engineering
STUDY OF THE REGRESSION RATE IN HYBRID PROPELLANT ROCKET ENGINES USING A CFD TOOL
Submission Author:
Loreto Pizzuti , SP
Co-Authors:
Matheus Henrique Pacheco, Loreto Pizzuti
Presenter: Matheus Henrique Pacheco
doi://10.26678/ABCM.COBEM2021.COB2021-0506
Abstract
The use of Computational Fluid Dynamics (CFD) tools in the resolution of the flux field in combustion chambers of rocket engines with hybrid propellants has developed a lot in recent years. However, comprehensive models, which describe the complex interaction between the multiple relevant phenomena in the burning of these engines, are still limited and numerical simulations are often considered only as a qualitative tool in determining the thermo-fluid-dynamic field of the rocket. The present work proposal consists in a theoretical study of the regression rate of solid propellants in hybrid rocket engines, relating it to the main characteristic flow parameters. The simulations are performed using pre-defined mass flow rates of fuel and oxidant, gaseous component obeying the ideal gas law, chemical equilibrium within the pre-combustion chamber so that the gas remains with its initial composition without being affected by the nozzle, and calculating the rate of fuel mass flow as a function of wall heat flux. The main objective of this work is to test a commercial CFD tool - ANSYS Fluent - for the simulation of the regression process, using the steady-state non-viscous flow model, which numerically solves the equations for the conservation of mass, energy, and momentum. A simulation model was developed capable of representing the regression process in simple geometries of combustion chambers of rocket engines for hybrid propellant in non-reactive flow considering the paraffin pyrolysis temperature, which can be used as a basis for adding relevant phenomena such as combustion and radiation in hybrid rockets and for more complex geometries. As a secondary objective, it was tested the model's reproducibility on a second simple hybrid rocket engine geometry, contributing to the future definition of optimized geometries that help to reduce the loss of performance in fuel combustion through the analysis of the flow model worked here.
Keywords
Regression Rate, numerical simulations, Hybrid propulsion
