Eventos Anais de eventos
ENCIT 2022
19th Brazilian Congress of Thermal Sciences and Engineering
A TWO-DIMENSIONAL PARABOLIC MODEL FOR COMBUSTION CHAMBER SIMULATION
Submission Author:
Marcio Teixeira de Mendonca , SP
Co-Authors:
Erykson Marconny da Silva Costa, Marcio Teixeira de Mendonca, FERNANDO DE SOUZA COSTA, Cesar Addis Valverde Salvador
Presenter: Cesar Addis Valverde Salvador
doi://10.26678/ABCM.ENCIT2022.CIT22-0246
Abstract
Different propulsion systems can be used for attitude control and maneuvering of satellites. Liquid bipropellant thrusters present high specific impulses and can have thrust control. The development of these devices requires simulation models both for design and test bench planning and although nowadays there are very complex combustion models based on computational fluid dynamics, simple and fast models are required for preliminary studies. This paper presents a numerical model for the simulation of two-phase flows in combustion chambers based on the two-dimensional boundary layer equations in cylindrical coordinates. The liquid propellants are injected with a given droplet size distribution into a recirculating flow of combustion products. The boundary layer equations are discretized using finite differences and marched downstream, considering the evaporation and reaction of fuel and oxidizer from the droplets and mixing of the resulting products with the pre-existing gases in the combustion chamber. Eleven product species are considered (CO2, H2O, CO, H2, N2, O2, H, OH, O, NO, N). The evaporation model is based on a classic transfer number steady state formulation, where the droplet surface temperature is assumed close to the propellant boiling temperature. The present results consider the reaction of unsymmetrical dimetil-hidrazine (UMHD) with dinitrogen tetroxide (N2O4). Results considering vaporization distance dependence on droplet size, chamber pressure and total equivalence ratio are presented considering a radial variation of fuel and oxidizer mass flow rates. The 2D model results are compared to data from a previous one-dimensional model. Further developments of the model will consider other propellants and droplet size distributions based on the Rosin-Rammler distribution.
Keywords
Propulsion, combustion chamber., Reactive flows, Boundary Layer, Combustion
