Response function modeling in the study of longitudinal combustion instability by a quasi-1D eulerian solver

Combustion instability is characterized by strong nonlinearities. In order to correctly capture the phenomenon physics with low-order models, it is necessary to consider this fundamental feature. In the present work the capability of a quasi-1D Eulerian solver, associated to a pressure time lag response function, of reproducing the main characteristic of combustion instability, such as the amplitude of the limit cycle or the growth rates, is investigated through two test cases. A straight duct is rst considered and the obtained results are compared with data available in literature. The second test case is the CVRC combustor, installed at Purdue Univrsity. In both cases a parametric study is performed on the parameters dening the selected response function that are amplitude and characteristic time lag.