Integrated analysis of jet-engine core noise using a hybrid modeling approach

摘要

As further reductions in aircraft engine noise are realized, the relative importance of reducing engine-core noise increases. In this work, a representative engine flow-path is considered to examine the mechanisms by which direct and indirect core noise propagate through the engine and affect the far-field sound radiation. The flow-path consists of a model combustor, a single-stage turbine, a converging nozzle, a near-field jet, and far-field acoustic radiation. A combination of high-fidelity simulations and low-order semi-analytic models is used to represent the generation and propagation of disturbances through the flow-path. Particular details are provided for LES calculations of the combustion chamber, nozzle exhaust flow, and jet noise radiation. A one-way coupling procedure is employed for propagating disturbances from one stage of the calculations to the next. Results show substantial increase in far-field sound radiation due to fluctuations generated by the upstream engine core.