报告题目：A Unified Time-Domain/Frequency-Domain Methodology for ComputationalAcoustics

主讲人：Ramesh K. AGARWAL

报告时间：2017年11月29日(周三)14:20

报告地点：新主楼第1报告厅

报告内容简介：

A method for directly computing theacoustic signatures without a wave equation analogy is presented. The governingacoustic equations are derived from the unsteady Euler equations by linearizingabout a steady mean flow and assuming a single frequency disturbance. Apseudo-time variable is introduced and the entire set of equationsis driven toconvergence by a point-implicit four-stage Runge-Kutta time-marching finitevolume scheme. The spatial terms are discretized by a fourth-orderdispersion-relation-preserving scheme with a sixth-order dissipation operatorto damp out the physically non-realizable spurious modes which are the artifactof discretization. A new formulation of far-field radiation boundary conditionbased on the modal analysis of the similarity form of the linearized Eulerequations is presented along with the well-known Perfectly Matched Layer (PML)formulation. The method is applied to compute the acoustic radiation fromcompact and non-compact oscillating airfoils in the presence of mean flow,acoustic radiation due to blade-vortex-interaction and airfoil/gustinteractions, acoustic scattering from airfoils, and wave propagation in ducts.Results are compared with known analytical solutions and the results of otherinvestigators where applicable.

主讲人简介：

Dr. RameshK.Agarwal is the William PalmProfessor of Engineering in the department of Mechanical Engineering andMaterials Science at Washington University in St. Louis. From 1994 to 2001, hewas the Sam Bloomfield Distinguished Professor and Executive Director of theNational Institute for Aviation Research at Wichita State University in Kansas.From 1978 to 1994, he was the Program Director and McDonnell Douglas Fellow atMcDonnell Douglas Research Laboratories in St. Louis. Dr. Agarwal received PhDin Aeronautical Sciences from Stanford University in 1975, M.S. in AeronauticalEngineering from the University of Minnesota in 1969 and B.S. in MechanicalEngineering from Indian Institute of Technology, Kharagpur, India in 1968. Overa period of 40 years, Professor Agarwal has worked in various areas ofComputational Science and Engineering - Computational Fluid Dynamics (CFD),Computational Acoustics and Electromagnetics, and Multi-disciplinary DesignOptimization. He is the author and coauthor of over 250 archival publications.He has given many plenary, keynote and invited lectures at various national andinternational conferences worldwide in over sixty countries.