Modelling of sound generation by turbulent reacting flows
نویسندگان
چکیده
The two components of combustion noise, namely the direct noise induced by heat release fluctuations in the flow and the indirect noise caused by acceleration of entropy perturbations through mean flow gradients resulting in acoustic radiation, are examined by considering different types of inhomogeneous wave equations deduced from the balance equations of fluid dynamics. This is accomplished by adapting acoustic analogies initially derived by Lighthill (1952), Phillips (1960) and Lilley (1972) for non-reactive flows to the reacting case. This reformulation is based on a standard set of assumptions borrowed from combustion. It is shown that a consistent formulation of a wave operator and its associated source terms is required.
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