Flame stabilization in high enthalpy supersonic flows: Experiments and simulations

Thakor, N and Miranda, C and Chaudhuri, S (2020) Flame stabilization in high enthalpy supersonic flows: Experiments and simulations. In: AIAA Scitech 2020 Forum, 6 - 10 January 2020, Orlando.

PDF AIAA_2020.pdf - Published Version Restricted to Registered users only Download (4MB) | Request a copy

Abstract

Detailed understanding of ignition, flame stabilization, extinction, and flame blowoff limits towards realizing sustained combustion in high enthalpy supersonic flows, demands sophisticated experimental studies and high fidelity simulations of the relevant physico-chemical processes. In this paper, two distinct approaches: experiments and simulations are employed to study the combustion of hydrogen in supersonic flow of air at flight relevant conditions. We successfully carried out the combustion of gaseous hydrogen fuel in high enthalpy supersonic flow with infield strut as fuel injector and flame holder. The objectives achieved during the test are: i) auto-ignition of hydrogen at an overall equivalence ratio = 0.16, ii) Visualisation of stable hydrogen-air flame behind the strut, iii) static wall pressure measurements. In these tests, combustion entry conditions were a stagnation pressure of 5.66 bar and a stagnation temperature of 1473 K at Mach number=2.2. These conditions successfully auto-ignited hydrogen, which was visualized in the optically accessible combustor. Secondly, an experimental case for wall injection of hydrogen jet parallel to supersonic flow, as demonstrated by Burrows at Lewis Research Center, NASA is used as the reference case to establish and validate the computational methodology. Available profiles of Mach number, total temperature, hydrogen and water mole fraction, measured at the exit of the combustor are in good agreement with the simulation data obtained with detailed chemical kinetics of hydrogen-air combustion. The implementation of accurate chemical kinetics in CFD simulations enhances predictive capabilities, as demonstrated. Subsequently, the wall pressure measurements of the present in-house experiments are predicted with reasonable accuracy. © 2020, American Institute of Aeronautics and Astronautics Inc, AIAA. All rights reserved.

Item Type:	Conference Paper
Publication:	AIAA Scitech 2020 Forum
Publisher:	American Institute of Aeronautics and Astronautics Inc, AIAA
Additional Information:	The copyright for this article belongs to American Institute of Aeronautics and Astronautics Inc, AIAA.
Keywords:	Aviation; Combustors; Computational fluid dynamics; Enthalpy; Flight simulators; Hydrogen; Ignition; Mach number; NASA; Pressure measurement; Stabilization; Struts; Supersonic aerodynamics; Supersonic aircraft; Supersonic flow; Wall flow, Combustion of hydrogens; Computational methodology; Detailed chemical kinetic; High-fidelity simulations; Hydrogen-air combustion; Physicochemical process; Predictive capabilities; Wall pressure measurement, Hydrogen fuels
Department/Centre:	Division of Mechanical Sciences > Aerospace Engineering(Formerly Aeronautical Engineering)
Date Deposited:	07 Feb 2023 11:14
Last Modified:	07 Feb 2023 11:14
URI:	https://eprints.iisc.ac.in/id/eprint/80027

Actions (login required)

View Item