Aircraft Engine Noise Scattering - A Discontinuous Spectral Element Approach

The paper presents a time-domain method for computation of sound radiation from aircraft engine sources to the far-field. The effects of nonuniform flow around the aircraft and scattering of sound by fuselage and wings are accounted for in the formulation. Our approach is based on the discretization of the inviscid flow equations through a collocation form of the Discontinuous Galerkin spectral element method. An isoparametric representation of the underlying geometry is used in order to take full advantage of the spectral accuracy of the method. Largescale computations are made possible by a parallel implementation based on message passing. Results obtained for radiation from an axisymmetric nacelle alone are compared with those obtained when the same nacelle is installed in a generic con.guration, with and without a wing.

[1]  Yusuf Özyörük,et al.  Computation of Sound Radiating from Engine Inlets , 1996 .

[2]  M. Y. Hussaini,et al.  Some Remarks on the Accuracy of a Discontinuous Galerkin Method , 2000 .

[3]  W. J. Gordon,et al.  Construction of curvilinear co-ordinate systems and applications to mesh generation , 1973 .

[4]  David A. Kopriva,et al.  Dispersion Analysis for Discontinuous Spectral Element Methods , 2000, J. Sci. Comput..

[5]  Walter Eversman,et al.  Wave Envelope and Finite Element Approximations for Turbofan Noise Radiation in Flight , 1986 .

[6]  F. Farassat,et al.  Ducted-Fan Engine Acoustic Predictions Using a Navier-Stokes Code , 1998 .

[7]  P. Roe.  Approximate Riemann Solvers, Parameter Vectors, and Difference Schemes , 1997 .

[8]  T. A. Zang,et al.  Spectral methods for fluid dynamics , 1987 .

[9]  Chi-Wang Shu,et al.  The Runge-Kutta local projection discontinuous Galerkin finite element method for conservation laws. IV. The multidimensional case , 1990 .

[10]  M. Nallasamy.  Computation of Noise Radiation from Fan Inlet and Aft Ducts , 1997 .

[11]  Chi-Wang Shu,et al.  TVB Runge-Kutta local projection discontinuous Galerkin finite element method for conservation laws III: one-dimensional systems , 1989 .

[12]  T. G. Sofrin,et al.  Modal propagation angles in a cylindrical duct with flow and their relation to sound radiation , 1979 .

[13]  W. Habashi,et al.  2N-Storage Low Dissipation and Dispersion Runge-Kutta Schemes for Computational Acoustics , 1998 .

[14]  M. Y. Hussaini,et al.  An Analysis of the Discontinuous Galerkin Method for Wave Propagation Problems , 1999 .

[15]  Wagdi G. Habashi,et al.  Multidomain Spectral Computations of Sound Radiation from Ducted Fans , 1999 .

[16]  M. Y. Hussaini,et al.  Discontinuous Spectral Element Approximation of Maxwell’s Equations , 2000 .