STUDIES OF FINITE-RATE EFFECTS RELEVANT TO MODELING OF LIQUID-PROPELLANT ROCKET COMBUSTION INSTABILITIES
Abstract
The present proposal addresses effects of realistic fuel chemistry on acoustic combustion instabilities in liquid-propellant rocket engines. Rate-ratio asymptotic analyses will be combined with numerical simulations to facilitate understanding of chemical-acoustic interactions stemming from the existence of different chemical time scales. New understanding and improved predictive capabilities will be developed in connection with two critical aspects of the problem.(i) A recently developed unsteady counterflow-flame formulation will be employed to generate unsteady flamelet models accounting for periodic oscillations of the background pressure, needed for improved subgrid modeling of LES computations of acoustically perturbed combustion processes and limit-cycle phenomena. (ii) The nonlinear temporal dynamics of edge and triple flames in the unsteady near-injector region will be investigated to parametrize the flame response under pressure and velocity oscillations, including effects of frequency and fluctuation amplitude on edge-flame velocity and on critical conditions for flame-anchoring, lift-off, and blow-off. The results of the project will serve to advance fundamental knowledge pertaining to the interplay of the acoustic field with the reactive flow in realistic scenarios, and to improve modeling tools for predicting the instability behavior of liquid-propellant rocket engines.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Aug 12, 2021
- Source ID
- FA95502010431
Entities
People
- Antonio Sanchez
Organizations
- Air Force Office of Scientific Research
- United States Air Force
- University of California, San Diego