同轴超临界射流掺混模态调控的大涡模拟  

Large Eddy Simulation of Coaxial Supercritical Jet Mixing Under Mode Control

作　　者：冯岩岩 原敏鹏 向勇 王存海 FENG Yanyan;YUAN Minpeng;XIANG Yong;WANG Cunhai(Beijing Key Laboratory of Process Fluid Filtration and Separation,College of Mechanical and Transportation Engineering,China University of Petroleum,Beijing 102249,China;School of Energy and Environmental Engineering,University of Science and Technology Beijing,Beijing 100083,China)

机构地区：[1]中国石油大学(北京)机械与储运工程学院,过程流体过滤与分离技术北京市重点实验室,北京102249 [2]北京科技大学能源与环境工程学院,北京100083

出　　处：《工程热物理学报》2024年第11期3323-3330,共8页Journal of Engineering Thermophysics

基　　金：国家自然科学基金资助项目(No.52306061)。

摘　　要：为增强同轴超临界射流的掺混特性,对自然射流和采用模态控制方法的激励射流流场开展了大涡模拟。结果表明:在15%振幅的曲张和扑动模态激励下,射流的密度、温度和速度势核长度分别缩短了42.9%、42.4%和23.3%,增强混合的效果较好,而螺旋模态激励的增混效果较差;曲张和扑动模态激励有效减弱了固壁效应和密度分层,径向速度脉动更加剧烈,动量混合增强,同时热容屏障被削弱,传热得到强化;螺旋模态激励对流场高密度梯度的改善微弱,且无法有效地削弱热容屏障,射流动量混合和传热的增强效果较差;本征正交分解的结果显示,速度场的低阶分量占据总能量的较大比例,主导了流动,曲张和扑动激励显著增强了流场下游的一阶分量,而螺旋模态的增强效果微弱。To enhance the mixing characteristics of the coaxial supercritical jet,large eddy simulations were carried out to study the flow field of natural jets and excited jets under mode control.Results show that under varicose and flapping mode excitation with 15%amplitude,the jet core lengths of density,temperature,and velocity are reduced by 42.9%,42.4%,and 23.3%,respectively.Mixing enhancement of helical mode is less effective.Under varicose and flapping mode excitation,the solid wall effect and density stratification are effectively weakened.The radial velocity pulsation becomes more intense,indicating enhanced momentum mixing.The thermal shield of heat capacity is also weakened,leading to strengthened heat transfer.Under the helical mode excitation,the high-density gradient and the thermal shield are weakened slightly.The enhancement effect of jet momentum mixing and heat transfer are not as pronounced.The results of proper orthogonal decomposition show that the low-order components of the velocity field occupy a large proportion of the total energy and dominate the flow.The first-order component of the downstream flow field is enhanced significantly by varicose and flapping excitations,while the enhancement effect of the helical mode is weak.

关 键 词：同轴超临界射流 射流混合增强 模态控制 湍流混合 

分 类 号：V434.13[航空宇航科学与技术—航空宇航推进理论与工程]