Prediction of the Acoustic Losses of a Swirl Atomizer Nozzle Under Non-Reactive Conditions
Prediction of the Acoustic Losses of a Swirl Atomizer Nozzle Under Non-Reactive Conditions
复制标题
非反应条件下旋流雾化喷嘴的声学损失预测
DOI：
10.1115/gt2013-95449
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发表时间：
2013
期刊：
影响因子：
2.5
通讯作者：
F. Turrini
中科院分区：
文献类型：
--
作者：
Jannis Gikadi;Wolfram C. Ullrich;T. Sattelmayer;F. Turrini
在预测燃气轮机燃烧室中的燃烧不稳定性时，通常会忽略复杂的几何形状和三维流动配置。然而，这些可能会对系统的整体声阻尼行为产生重大影响。控制燃烧室内部流动的一个重要元件是旋流雾化器喷嘴。其中，流动被加速并且产生涡流流体运动。在其出口处达到相当高的流速并形成多个剪切层，这些剪切层排放到燃烧室中。为了预测这些环境中的阻尼效应，需要考虑声流相互作用过程。这些涉及剪切层中入射声波的散射和折射、与不稳定流体动力剪切层的声相互作用以及声墙相互作用过程。可以使用声散射矩阵来研究它们的综合效应。在本文中，预测了 Avio 开发的贫喷射系统在非反应条件下的声散射行为，并与实验进行了比较。数值方法非常通用，工作原理如下：首先，使用雷诺平均纳维-斯托克斯湍流模型计算流体动力场。然后，在先前计算的平均流动状态周围的频率空间中求解线性化纳维-斯托克斯方程。考虑了喷嘴结构的复杂三维度及其相应的流场。将结果与旋流雾化器喷嘴在大气和升高的入口温度下的实验测量结果进行比较。结果表明，可以准确捕获散射行为以及声流相互作用。版权所有 © 2013 ASME
When predicting combustion instabilities in gas turbine combustion chambers, the complex geometry and three dimensional flow configurations are often neglected. However, these may have significant influence on the overall acoustic damping behavior of the system. An important element governing the flow inside a combustion chamber is the swirl atomizer nozzle. Therein, the flow is accelerated and a swirling fluid motion is imposed. At its exit considerable high flow velocities are reached and multiple shear layers are formed which discharge into the combustion chamber. To predict damping effects in these environments, acoustic-flow interaction processes need to be taken into account. These involve scattering and refraction of incident acoustic waves in shear layers, acoustic interaction with the unstable hydrodynamic shear layers as well as acoustic wall interaction processes. Their combined effect can be studied using acoustic scattering matrices. In this paper the acoustic scattering behavior of a lean injection system developed by Avio is predicted under non-reactive conditions and compared to experiments. The numerical method is very general and works as follows: First, the fluid dynamic field is computed using a Reynolds averaged Navier-Stokes turbulence model. Then, the linearized Navier-Stokes equations are solved in frequency space around the previously computed mean flow state. The complex three dimensionality of the nozzle configuration is taken into account as well as its corresponding flow field. Results are compared against experimental measurements of a swirl atomizer nozzle at atmospheric and elevated inlet temperatures. It is shown that the scattering behavior and therefore the acoustic-flow interactions are captured accurately.Copyright © 2013 by ASME