Bin Jonghoon, Yousuff Hussaini M, Lee Soogab
Department of Mathematics, Florida State University, Tallahassee, Florida 32306, USA.
J Acoust Soc Am. 2009 Feb;125(2):664-75. doi: 10.1121/1.2999339.
An accurate and practical surface impedance boundary condition in the time domain has been developed for application to broadband-frequency simulation in aeroacoustic problems. To show the capability of this method, two kinds of numerical simulations are performed and compared with the analytical/experimental results: one is acoustic wave reflection by a monopole source over an impedance surface and the other is acoustic wave propagation in a duct with a finite impedance wall. Both single-frequency and broadband-frequency simulations are performed within the framework of linearized Euler equations. A high-order dispersion-relation-preserving finite-difference method and a low-dissipation, low-dispersion Runge-Kutta method are used for spatial discretization and time integration, respectively. The results show excellent agreement with the analytical/experimental results at various frequencies. The method accurately predicts both the amplitude and the phase of acoustic pressure and ensures the well-posedness of the broadband time-domain impedance boundary condition.
已开发出一种精确且实用的时域表面阻抗边界条件，用于航空声学问题中的宽带频率模拟。为展示该方法的能力，进行了两种数值模拟，并与解析/实验结果进行比较：一种是单极源在阻抗表面上的声波反射，另一种是声波在具有有限阻抗壁的管道中的传播。单频和宽带频率模拟均在线性化欧拉方程框架内进行。分别使用高阶保色散关系有限差分法和低耗散、低色散龙格 - 库塔法进行空间离散化和时间积分。结果表明，在各种频率下与解析/实验结果都有很好的一致性。该方法能准确预测声压的幅度和相位，并确保宽带时域阻抗边界条件的适定性。
