自激励冲击射流流动与传热的机理研究

项目名称： 自激励冲击射流流动与传热的机理研究

项目编号： No.51206153

项目类型： 青年科学基金项目

立项/批准年度： 2013

项目学科： 工程热物理与能源利用学科

项目作者： 耿丽萍

作者单位： 中国计量学院

项目金额： 25万元

中文摘要： 初始及边界条件完全均匀对称的射流，在一定结构下由于柯恩达效应会发生流体的自维持振荡，形成自激励旋进流动，这是一种由系统内部因素引起的非线性现象。本项目通过实验与数值模拟相结合来研究自激励冲击射流中的柯恩达效应和自维持振荡，着重研究非线性特征出现的条件，形成和发展的过程及其对流动和传热的影响。实验采用热线风速仪对流场进行瞬时速度测量，用PDA和PIV对流场变化进行观测，并结合射流冲击传热特性进行相关分析；数值模拟是研究非线性问题的有效方法，但算法精度、数值模型的可靠性是研究工作进行的重要保证。经过实验验证的数值模型可以研究多种参数下的自激励冲击射流流动与传热的特点，尤其是入口雷诺数从小到大的变化过程中也就是流动从层流向湍流发展过程中分岔、振荡的产生、发展及其对流动和传热的影响，探索射流流动与传热中非线性现象的物理机理。

中文关键词： 自激励射流；自维持振荡；流场；传热；

英文摘要： The self -excited precessing jet and self-sustained oscillation caused by Coanda effect could be formed in some kind of configuration even when the initial conditions are steady and the boundary conditions are quite symmetry. This is a nonlinear phenomena caused by internal inherently instability of the flow field. The researches to Coanda effect and self-sustained oscillation in the flow field of self-excited precessing jet are going to be carried out by experimental studies and numerical simulations in this project. The basic conditions that nonlinear phenomena appeared need to be found out and how the oscillation formed and developed need to be studied. The influence of such oscillation to the heat transfer also need to be explored. The hot-wire anemometer is used to test the instantaneous flow field. The PDA and PIV are used to watch the change of the whole flow field. The heat transfer characteristics will be tested and analyzed in combine with the flow field distributions. Numerical simulation is a good method to study the oscillation and nonlinear characteristics. However, the accuracy of the algorithm and the reliability of simulation model need to be tested by experimental results to guarantee the execution of the simulations. The heat transfer and flow characteristics of self -excited impinging jet be

英文关键词： self-excited jet；self-sustained oscillation；flow field；heat transfer；