LINEARIZED EULER EQUATIONS FOR THE PREDICTION OF LINEAR HIGH-FREQUENCY STABILITY IN GAS TURBINE COMBUSTORS
LINEARIZED EULER EQUATIONS FOR THE PREDICTION OF LINEAR HIGH-FREQUENCY STABILITY IN GAS TURBINE COMBUSTORS
复制标题
预测燃气轮机燃烧室线性高频稳定性的线性欧拉方程
DOI：
10.1115/1.4034453
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发表时间：
2016
影响因子：
1.5
通讯作者：
T. Sattelmayer
中科院分区：
文献类型：
--
作者：
M. Schulze;T. Hummel;Noah Klarmann;F. Berger;B. Schuermans;T. Sattelmayer
提出了一种新的燃气涡轮机燃烧室高频热声振荡线性稳定性分析方法。该方法是基于线性欧拉方程（LEE），它产生一个高保真度的描述声波的传播和阻尼在复杂的，不均匀的，反应性的平均流环境，如遇到的气体涡轮机燃烧室。具体而言，这项工作介绍了三个新的社区：（1）线性化的欧拉方程的基础上的线性稳定性分析。(2)明确考虑尖叫级频率下的三维声振荡，特别是第一横向模式。(3)非紧凑火焰与LEE耦合的处理，即由于小声波波长引起的扰动和不稳定火焰响应之间的空间变化耦合动力学。两种不同的配置的实验模型燃烧室的热功率和质量流量的分析的主题。线性火焰驱动是通过规定的非定常热释放源项的线性化欧拉方程的局部火焰传递函数，这是从第一原理检索。所需的稳态流场是通过计算流体动力学（CFD），这是基于一个扩展的火焰生成歧管（FGM）燃烧模型，考虑到热传递到环境中的数值获得。因此，该模型非常适合于这种类型的燃烧室。的配置进行了模拟，热声特征在于与第一横向模式的本征频率和增长率。实验观察到的热声稳定性特性的研究结果进行了验证。在结果的基础上，讨论了对声场的新见解。
A novel methodology for linear stability analysis of high-frequency thermoacoustic oscillations in gas turbine combustors is presented. The methodology is based on the linearized Euler equations (LEEs), which yield a high-fidelity description of acoustic wave propagation and damping in complex, nonuniform, reactive mean flow environments, such as encountered in gas turbine combustion chambers. Specifically, this work introduces three novelties to the community: (1) linear stability analysis on the basis of linearized Euler equations. (2) Explicit consideration of three-dimensional, acoustic oscillations at screech level frequencies, particularly the first-transversal mode. (3) Handling of noncompact flame coupling with LEE, that is, the spatially varying coupling dynamics between perturbation and unsteady flame response due to small acoustic wavelengths. Two different configurations of an experimental model combustor in terms of thermal power and mass flow rates are subject of the analysis. Linear flame driving is modeled by prescribing the unsteady heat release source term of the linearized Euler equations by local flame transfer functions, which are retrieved from first principles. The required steady-state flow field is numerically obtained via computational fluid dynamics (CFD), which is based on an extended flamelet-generated manifold (FGM) combustion model, taking into account heat transfer to the environment. The model is therefore highly suitable for such types of combustors. The configurations are simulated, and thermoacoustically characterized in terms of eigenfrequencies and growth rates associated with the first-transversal mode. The findings are validated against experimentally observed thermoacoustic stability characteristics. On the basis of the results, new insights into the acoustic field are discussed.