Multi-dimensional numerical simulation of sound propagation with background flow using constrained interpolation profile method

Abstract

To date, numerical simulation for sound wave propagation has been widely investigated as a result of advances in computer technology. For acoustic imaging and prediction, the development of accurate and effective analysis methods in time domain has become an important technical issue. The constrained interpolation profile (CIP) method, a novel low-dispersive numerical scheme, is a type of method of characteristics (MOC) employing a co-located grid system. In our past study, we have applied the CIP method to solving the linearized sound propagation equation. MOC is the calculation method which transforms governing equations of acoustic field into advection equations to solve the acoustic fields. Therefore, the method should be suitable for solving sound propagation considering the background flow effect, e.g., prediction of sound noise environment generated from a propulsion system of aircrafts or rockets. In the study, we proposed and examined the calculation method of sound propagation in an arbitrary background flow using CIP method. We made a numerical comparison between proposed method and the linearized Euler equations (LEE) method. The presentation has clarified that the CIP method is more accurate and effective for solving sound propagation in a strong and/or heterogeneous background flow.