School of Mechanical Engineering, University of Adelaide, Adelaide, Australia.
Laboratoire Roberval, Université de Technologie Compiègne, Compiègne, Cedex, France.
J Acoust Soc Am. 2023 Jul 1;154(1):217-231. doi: 10.1121/10.0020069.
An analysis has been carried out to investigate the sound radiation through a heated jet in cooler cross-flow, which is representative of many industrial exhaust systems, using a hybrid steady-state computational fluid dynamics and computational acoustic model. The mean flow and temperature fields are modelled using steady-state computational fluid dynamics, with the turbulence modelled using Reynolds Averaged Navier-Stokes equations. The corresponding mean flow and temperature fields are used in the computational sound propagation model using linearised acoustic wave equation with mean flow based on a scalar flow potential. The results obtained from the computational simulations show that the flow significantly changes the sound propagation path and that the sound levels downstream of the duct outlet are higher than expected from using an acoustic monopole radiation pattern. The dominant mechanism affecting the propagation of sound is the refraction arising from the plume's temperature and velocity gradients. The sound propagation is highly dependent on the proximity from the duct outlet, normalised wavenumber, temperature and the jet to cross-flow mean velocity ratio. This computational study builds upon previous experimental work to analyse the fluid-acoustic interaction for heated jets in cooler cross-flow to understand the complex radiation pattern that leads to higher-than-expected sound levels downstream of the duct outlet.
已经进行了一项分析，以使用混合稳态计算流体动力学和计算声学模型研究通过较冷横流中的加热射流的声辐射，这代表了许多工业排气系统。使用稳态计算流体动力学对平均流场和温度场进行建模，使用雷诺平均纳维-斯托克斯方程对湍流进行建模。在计算声传播模型中，使用基于标量流势的线性声波方程，使用平均流来使用相应的平均流和温度场。计算模拟得到的结果表明，流场会显著改变声音传播路径，并且管道出口下游的声音水平高于使用声学单极辐射模式的预期。影响声音传播的主要机制是射流的温度和速度梯度引起的折射。声音传播高度依赖于管道出口的接近程度、归一化波数、温度以及射流与横流平均速度比。这项计算研究建立在前人实验工作的基础上，以分析较冷横流中加热射流的流固耦合相互作用，以了解导致管道出口下游声音水平高于预期的复杂辐射模式。
