Toward a near-field CAA-CFD coupling approach: Application to a centrifugal blower

Centrifugal blowers are widely used in heating, ventilation and air-conditioning to gen-erate high mass flow in compact geometries. Confined configurations imply important interactions between the impeller and the volute casing, which causes acoustic tonal noise. This study is focused on the simulation of the noise propagation into a subsonic centrifu-gal blower. In this con?ned domain, integral methods in acoustic reach their limits since they do not take into account reflection and diffraction. Instead, this near-field propaga-tion issue is tackled here by the use of a wave propagation operator such as Linearized Perturbed Compressible Equations (LPCE). First, a simple acoustic source model is pro-posed. Then, sources are extracted from CFD computations. This two kind of sources are experimented as inputs into the propagation operator. Spatial resolution is enforced by a high order finite volume CAA solver (FV-MLS). The moving parts are taken into account through an innovative sliding-mesh approach.

[1]  N. Curle.  The influence of solid boundaries upon aerodynamic sound , 1955, Proceedings of the Royal Society of London. Series A. Mathematical and Physical Sciences.

[2]  J. Trépanier,et al.  A finite-volume method for the Euler equations on arbitrary Lagrangian-Eulerian grids , 1991 .

[3]  J. Hardin,et al.  An acoustic/viscous splitting technique for computational aeroacoustics , 1994 .

[4]  S. Jun,et al.  Multiresolution reproducing kernel particle methods , 1997 .

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

[6]  R. Lewis,et al.  Low-storage, Explicit Runge-Kutta Schemes for the Compressible Navier-Stokes Equations , 2000 .

[7]  Y. Moon,et al.  Discrete Noise Prediction of Variable Pitch Cross-Flow Fans by Unsteady Navier-Stokes Computations , 2003 .

[8]  Y. Moon,et al.  Computation of unsteady viscous flow and aeroacoustic noise of cross flow fans , 2003 .

[9]  Fermín Navarrina,et al.  Finite volume solvers and movingleast-squares approximations for thecompressible Navier-Stokes equations onunstructured grids , 2007 .

[10]  J. Seo,et al.  Perturbed Compressible Equations for Aeroacoustic Noise Prediction at Low Mach Numbers , 2005 .

[11]  F. Navarrina,et al.  High‐order finite volume schemes on unstructured grids using moving least‐squares reconstruction. Application to shallow water dynamics , 2006 .

[12]  Jung Hee Seo,et al.  Linearized perturbed compressible equations for low Mach number aeroacoustics , 2006, J. Comput. Phys..

[13]  R. Ballesteros-Tajadura,et al.  Numerical Calculation of Pressure Fluctuations in the Volute of a Centrifugal Fan , 2006 .

[14]  S. Piperno,et al.  TIME-DOMAIN PARALLEL SIMULATION OF HETEROGENEOUS WAVE PROPAGATION ON UNSTRUCTURED GRIDS USING EXPLICIT, NONDIFFUSIVE, DISCONTINUOUS GALERKIN METHODS , 2006 .

[15]  F. Bakir,et al.  Influence of Impeller Geometry on the Unsteady Flow in a Centrifugal Fan: Numerical and Experimental Analyses , 2007 .

[16]  Farid Bakir,et al.  Predicting tonal noise from a high rotational speed centrifugal fan , 2008 .

[17]  Xesús Nogueira,et al.  Resolution of computational aeroacoustics problems on unstructured grids with a higher-order finite volume scheme , 2010, J. Comput. Appl. Math..

[18]  X. Nogueira,et al.  Toward a Higher Order Unsteady Finite Volume Solver Based on Reproducing Kernel Methods , 2011 .

[19]  Stéphane Moreau,et al.  Numerical simulations of a low-speed radial fan , 2012 .

[20]  S. Redonnet,et al.  Aircraft noise prediction via aeroacoustic hybrid methods - development and application of onera tools over the last decade : some examples. , 2014 .

[21]  Manuel Henner,et al.  Toward a High-Order Preserving Sliding-Mesh Approach for Computational Aeroacoustics in Subsonic Turbomachinery , 2015 .

[22]  Luis Ramírez,et al.  New high-resolution-preserving sliding mesh techniques for higher-order finite volume schemes , 2015 .

[23]  M. Deligant,et al.  High-order aeroacoustics propagation solver with sliding-mesh capabilities for subsonic turbomachinery , 2016 .