槽道非定常流场脉动特性的POD分析

发布时间：2018-04-25 18:42

本文选题：槽道流 + 非定常流场　；参考：《仪器仪表学报》2017年03期

【摘要】：针对槽道内非定常流场的脉动程度是影响传质、传热的效率问题,通过构建2DPIV测量非定常流场瞬态速度矢量场的实验系统,分析了2DPIV测量的各个时刻矢量场和涡量分布的形态,获取了非定常流场的循环周期和频率;利用本征正交分解(POD)技术分解了2DPIV的测量非定常流场的瞬态速度矢量场,根据各个模态的能量比,选取前16阶模态作为非定常流场的主导结构模态,并对POD分解的前16阶模态系数进行功率谱分析;结果表明POD分解的低阶模态分别表征了非定常流场的基频和相应的倍频,阐明了非定常流场的脉动机理;非定常流场的脉动是由于一些涡列和余弦形式的波状主流形成的,并将这些涡列以及伴随的波状主流的脉动频率映射到POD分解的低阶主导模态系数上。
[Abstract]:In view of the fact that the pulsation degree of unsteady flow field in channel is the efficiency of mass transfer and heat transfer, an experimental system for measuring transient velocity vector field of unsteady flow field by 2DPIV is constructed, and the patterns of vector field and vorticity distribution at different times measured by 2DPIV are analyzed. The cycle period and frequency of the unsteady flow field are obtained, and the transient velocity vector field of the unsteady flow field measured by 2DPIV is decomposed by the eigenorthogonal decomposition technique, according to the energy ratio of each mode. The first 16 modes are selected as the dominant structural modes of the unsteady flow field, and the power spectrum analysis of the first 16 order modal coefficients of the POD decomposition is carried out. The results show that the low order modes of the POD decomposition represent the fundamental frequency and the corresponding doubling frequency of the unsteady flow field, respectively. The pulsation mechanism of unsteady flow field is explained. The pulsation frequencies of these vortices and the accompanying waves are mapped to the low order dominant modal coefficients of the POD decomposition.
【作者单位】：重庆工商大学废油资源化技术与装备工程研究中心;
【基金】：国家自然科学基金(51375516) 重庆基础与前沿研究(cstc2016jcyj A0185)项目资助
【分类号】：O35

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