摘要
为分析贫油预混预蒸发(LPP)燃烧室的燃烧不稳定(CI)特征,通过对三维亥姆霍兹方程进行了三种不同程度的简化:平均温度场和导入CFD温度场的无源项方程,以及导入燃烧流场特征的有源项方程,分别对单头部LPP燃烧室模型进行了三维频域特征数值仿真。结果表明:燃烧室内的温度分布是燃烧室声学特征频率的重要影响因素,释热率源项对主频无影响。相比于仅设置平均温度场,导入CFD三维温度场可以获得与实验频率更吻合的结果,精度提高了5%。采用解耦方式求解频域方程能够快速建立声学系统与燃烧流场间的联系,释热率和迟滞时间的空间分布特征表现在亥姆霍兹方程的源项,其对预测燃烧室固有频率没有影响,但是能够获得详细声压分布特征。
In order to analyze the combustion instability(CI)characteristics of lean premixed prevaporized(LPP)combustor,three-dimensional Helmholtz equations were simplified at three different levels.The average temperature field equation without source term,the imported CFD temperature field equation without source term,and the imported combustion flow field characteristics equation with source term,were respectively simulated for the single-head LPP combustor model in three-dimensional frequency domain.The results showed that the temperature distribution in the combustor was an important factor affecting the acoustic eigenfrequency of the combustor,and the source term of heat release rate had no effect on the main frequency.Compared with only setting of average temperature field,importing the 3D temperature field calculated by CFD can obtain more consistent results with the experimental frequency,and the accuracy was increased by 5%.The relationship between the acoustic system and the combustion flow field can be quickly established by solving the frequency domain equation in a decoupling way.The spatial distribution characteristics of heat release rate and hysteresis time were represented by the source term of the Helmholtz equation,which had no effect on the prediction of the natural frequency of the combustion chamber,but the detailed sound pressure distribution characteristics can be obtained.
作者
李昊
刘勇
张祥
王旭怀
杨晨
刘重阳
LI Hao;LIU Yong;ZHANG Xiang;WANG Xuhuai;YANG Chen;LIU Chongyang(College of Energy and Power Engineering,Nanjing University of Aeronautics and Astronautics,Nanjing 210016,China;School of Power and Energy,Northwestern Polytechnical University,Xi’an 710072,China;Sichuan Gas Turbine Research Institute,Aero Engine Corporation of China,Mianyang Sichuan 621000,China)
出处
《航空动力学报》
EI
CAS
CSCD
北大核心
2024年第3期52-61,共10页
Journal of Aerospace Power
基金
中国航发自主创新专项资金(ZZCX-2019-009)。
