Numerical study on transverse combustion instability in liquid propellant rocket engines for the achievement of predictive capability using a simplified model
The a-priori prediction of high frequency combustion instability will certainly favorably impact on the development costs of new liquid propellant rocket engines. Achieving such objective with a low order model implies a significant reduction of the experimental efforts and costs, as well as those of the massive high-fidelity numerical simulations, which are mandatory in order to investigate this problem.
An hybrid in-house 1D-3D Eulerian solver for multispecies flow is being developed to face the high-frequency instability problems. Such solver employs a one-dimensional description of the injectors flow field and a multi-D representation of the combustion chamber, so that the typical multi-dimensional propagation events of transverse instability can be reproduced. Its main purpose is to reproduce the driving effects that the injection system can have on the combustion chamber. Such coupling model has been developed and already successfully tested on a longitudinal instability test-case by means of a one-dimensional Eulerian solver.
The main goal of the proposed research is to achieve the capability to predict the coupling effects occurring between the injection dynamics, yielding to an oscillating heat release rate, and the chamber pressure oscillations characterizing the transverse combustion instability.