Application of POD Techniques to the Far Jet

POD技术在远航飞机上的应用

• 批准号: 9714367
• 负责人: William George
• 金额: $ 27万
• 依托单位: SUNY at Buffalo
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1997
• 资助国家: 美国
• 起止时间: 1997-11-15 至 2000-10-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9714367&HistoricalAwards=false
• 关键词: Application; POD; Techniques; Far; Jet

PROJECT SUMMARY The dynamics of the fully-developed axisymmetric far jet using Proper Orthogonal Decomposition (POD) techniques will be investigated experimentally. The overall goal is to obtain a better understanding of the structure of the far jet, and the degree to which its evolution is foreshadowed by the near jet. The experiment has two specific objective: * First, POD techniques will be applied to extensive measurements of the velocity cross-spectra in order to determine the eigenfunctions describing the far jet. * Second, the eigenfunctions determined will be used to reconstruct the instantaneous flow, both spatially and temporally, in whole or in part. The investigation will use two unique experimental apparatus: one a 138 hot-wire probe developed earlier to study the jet mixing layer; the other a flying array of 15 hot-wire, the spacing of which changes with downstream distance from the jet exit. These techniques will be used in conjunction the known one- and two-point similarity properties of the far jet to determine the spatial and temporal evolution of the POD eigenfunction which comprise the flow (including their streamwise dependence)

利用正交分解（POD）技术对完全发展的轴对称远射流动力学进行实验研究。总体目标是更好地了解远端喷流的结构，以及近端喷流预示其演变的程度。实验有两个具体目标：*首先，POD技术将应用于速度交叉光谱的广泛测量，以确定描述远喷流的特征函数。*第二，确定的特征函数将用于重建瞬时流，包括空间和时间，全部或部分。本次研究将使用两种独特的实验装置：一种是早期研制的用于研究射流混合层的138热线探针；另一个是由15根热线组成的飞行阵列，这些热线的间距随着距离射流出口的下游距离而变化。这些技术将与已知的远射流的一点和两点相似特性结合使用，以确定构成流的POD特征函数的时空演变（包括它们的流向依赖关系）。