Simulation du bruit d'écoulements anisothermes par méthodes hybrides pour de faibles nombres de Mach. (Noise computation of non isothermal flows by hybrid methods for low Mach numbers)
نویسنده
چکیده
Noise computation of non isothermal flows by hybrid methods for low Mach numbers This study focuses on the numerical calculation of the acoustic field radiated by subsonic turbulent flows with temperature inhomogeneities. Hybrid methods are developed through a Rayleigh-Janzen expansion of the Navier-Stokes equations. The flow is solved in a quasi-incompressible way then the acoustic disturbances are propagated by two methods : the linearized Euler’s equations (EEL) and the perturbed low Mach number approximation (PLMNA). The methods are validated on simple cases and then applied to an isothermal and non isothermal spatially evolving mixing layer.
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