A Ffowcs Williams-Hawkings Solver for Lattice-Boltzmann based Computational Aeroacoustics

This paper presents the development of an efficient far-field noiseprediction code using the near-field results from a Lattice-Boltzmann flow solver as input to an acoustic analogy solver. Two formulations, based on the Ffowcs Williams–Hawkings equation, are implemented to efficiently perform far-field prediction from large input data sets. For configuration where the noise source is moving through a fluid at rest (such as aircraft certification), the efficient and well-validated formulation 1A i s implemented. For windtunnel configurations where both the source and observer are stationary in a uniform flow, a formulation based on the Garrick Triangle, and referred to as GT, is used to increase the computational efficiency. Numerical simulations and far-field prediction are performed for three representative validation cases: a three-dimensional monopole source, a tandem cylinder flow, and a fan noise case. Comparisons of the results from the far-field solver show excellent agreement with the theoretical predictions and the available experimental data.

[1]  E. Fares.  Unsteady flow simulation of the Ahmed reference body using a lattice Boltzmann approach , 2006 .

[2]  X. Yuan,et al.  Kinetic theory representation of hydrodynamics: a way beyond the Navier–Stokes equation , 2006, Journal of Fluid Mechanics.

[3]  Kenneth S. Brentner,et al.  Maneuvering rotorcraft noise prediction , 2004 .

[4]  Bradley Duncan,et al.  The Lattice-Boltzmann-VLES Method for Automotive Fluid Dynamics Simulation, a Review , 2009 .

[5]  Luther N. Jenkins,et al.  Unsteady Flowfield Around Tandem Cylinders as Prototype for Component Interaction in Airframe Noise , 2005 .

[6]  Meelan Choudhari,et al.  Measurements of the Flowfield Interaction Between Tandem Cylinders , 2009 .

[7]  Shiyi Chen,et al.  LATTICE BOLTZMANN METHOD FOR FLUID FLOWS , 2001 .

[8]  Swen Noelting,et al.  Computational Aeroacoustics Validation and Analysis of a Nose Landing Gear , 2009 .

[9]  T. Brooks,et al.  Noise Radiation from Single and Multiple Rod Configurations , 2006 .

[10]  Richard Shock,et al.  Numerical study of flow past an impulsively started cylinder by the lattice-Boltzmann method , 2004, Journal of Fluid Mechanics.

[11]  Jean-Luc Adam,et al.  Aeroacoustic simulation of automotive ventilation outlets , 2008 .

[12]  Lawrence E. Kinsler,et al.  Fundamentals of acoustics , 1950 .

[13]  G. P. Succi,et al.  The prediction of helicopter rotor discrete frequency noise , 1982 .

[14]  F. Farassat,et al.  An Analytical Comparison of the Acoustic Analogy and Kirchhoff Formulation for Moving Surfaces , 1997 .

[15]  Meelan Choudhari,et al.  Measurements of Unsteady Wake Interference Between Tandem Cylinders , 2006, 36th AIAA Fluid Dynamics Conference and Exhibit.

[16]  Swen Noelting,et al.  A Hybrid Lattice-Boltzmann/FW-H Method to Predict Sources and Propagation of Landing Gear Noise , 2010 .

[17]  S. Noelting,et al.  Tandem Cylinder Noise Predictions Using Lattice Boltzmann and Ffowcs Williams-Hawkings Methods , 2010 .

[18]  Franck Perot,et al.  Investigation of the statistical properties of pressure loadings on real automotive side glasses , 2009 .

[19]  D. L. Hawkings,et al.  Sound generation by turbulence and surfaces in arbitrary motion , 1969, Philosophical Transactions of the Royal Society of London. Series A, Mathematical and Physical Sciences.

[20]  B. Shi,et al.  Discrete lattice effects on the forcing term in the lattice Boltzmann method. , 2002, Physical review. E, Statistical, nonlinear, and soft matter physics.

[21]  Virginie Maillard,et al.  Numerical Simulation of Wall Pressure Fluctuations on a Simplified Shape of Vehicle , 2003 .

[22]  Hudong Chen,et al.  Digital Physics Approach to Computational Fluid Dynamics: Some Basic Theoretical Features , 1997 .

[23]  David P. Lockard,et al.  A COMPARISON OF FFOWCS WILLIAMS-HAWKINGS SOLVERS FOR AIRFRAME NOISE APPLICATIONS , 2002 .

[24]  L. Mongeau,et al.  An Acoustic Analogy Formulation for Uniformly Moving Media: Formulation 1C , 2010 .

[25]  D. Casalino.  An advanced time approach for acoustic analogy predictions , 2003 .

[26]  Luther N. Jenkins,et al.  Characterization of Unsteady Flow Structures Around Tandem Cylinders for Component Interaction Studies in Airframe Noise , 2005 .

[27]  Thomas F. Brooks,et al.  Tandem Cylinder Noise Predictions , 2007 .

[28]  Raoyang Zhang,et al.  Efficient kinetic method for fluid simulation beyond the Navier-Stokes equation. , 2006, Physical review. E, Statistical, nonlinear, and soft matter physics.

[29]  F. Farassat,et al.  Modeling aerodynamically generated sound of helicopter rotors , 2003 .

[30]  Valana Wells,et al.  Acoustics of a moving source in a moving medium with application to propeller noise , 1995 .

[31]  Luc Mongeau,et al.  An acoustic analogy formulation for moving sources in uniformly moving media , 2011, Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences.

[32]  I. E. Garrick,et al.  A theoretical study of the effect of forward speed on the free-space sound-pressure field around propellers , 1953 .

[33]  G. Brès,et al.  Properties of the Lattice-Boltzmann Method for Acoustics , 2009 .

[34]  R. Shock,et al.  Lattice Boltzmann Simulations of the DLR -F4, DLR -F6 and Variants , 2008 .

[35]  F. Farassat.  Derivation of Formulations 1 and 1A of Farassat , 2007 .

[36]  Christophe Bailly,et al.  Numerical simulation of the unsteady flow past a cavity and application to the sunroof buffeting , 2001 .