Eventos Anais de eventos
ENCIT 2018
Brazilian Congress of Thermal Sciences and Engineering
HEAT FLUX AND THERMODYNAMIC PROPERTIES ANALYSIS AT THE STAGNATION POINT AND THE BLUNT REGION OF THE 14-X S SCRAMJET ENGINE
Submission Author:
Ana Maria Pereira Lara , SP , Brazil
Co-Authors:
Ana Maria Pereira Lara, Paulo Toro, Israel Rêgo, Tiago Rolim
Presenter: Ana Maria Pereira Lara
doi://10.26678/ABCM.ENCIT2018.CIT18-0462
Abstract
The scramjet engine 14-X S is a technological demonstrator of a hypersonic airbreathing propulsion system based on supersonic combustion. Scramjets are ideal as engines for hypersonic flights, so they are subjected to high heat flux loads, specifically on the leading edge. Thus, this paper applies the normal shock wave relations, the isentropic relations, the Fay and Riddell's theory and the Lees´s theory to study the thermodynamic properties and the aerodynamic heating at the stagnation point and in the blunt region of the 14-X S engine. Two models have been considered for the determination of the thermodynamic properties and for the calculation of the heat flux, being: calorically perfect gas and thermodynamic equilibrium gas. In the blunt region there are the incidence of a normal shock wave that decelerates the flow and increases the pressure and temperature. After the passage through the normal shock wave, the flow will be isentropically decelerated to the stagnation point, increasing again the pressure and the temperature. Increases in the values of thermodynamic properties cause the increase of the heat flux. The highest values of heat flux were found at the stagnation point. After this point, the heat flux had a reduction of about 96% along the blunt region. This showed the importance of the blunt region to soften the values of heat flux that will arrive in the flat sections.
Keywords
Heat flux, Scramjet, Hypersonic, Blunt body, Aerothermodynamics
