粒子成像测速系统的数据分析中粒子成像测速系统的数据分析检测方案

智能文字提取功能测试中

NASAChristina Darcie， NASA Glenn Research Center， Multicultural Undergraduates in Science and Technology， Penn State University Multipoint Lean-DirectInjection (MP-LDI) The performance of the MP-LDI istested by using a 9-point fuel injector(left) in a Jet-A fueled， flame tubecombustion rig. The MP-LDI rapidlymixes fuel and air so a stablecombustion reaction can occur withina short distance and reduces NO，emissions by reducing the peaktemperature. Particle Image Velocimetry (PIV) The PIV technique includes capturing hundreds of image pairs， microseconds apart， of the fuel drops or seededair during MP-LDI tests. The combustion rig has three fused silica windows in the reaction chamber， one on topand two on either side， each 2 x 1.5 inches wide and 0.5-inch thick. A Nd：YAG laser is transformed from itsoriginal point source into a laser sheet and is aimed vertically downward at the top window of the combustionchamber，and a 200-mm Nikon camera captures images of the illuminated particles through a side window. Vector images are derived from the correlation between image pairs takenmicroseconds apart.From these we can determine instantaneous velocity maps andaverages as well as root mean square velocities (RMS). The vector images display the flow during combustion and non-reacting， nonfuelcombustor flows. They identify the existence and locations of air-swirl inducedrecirculation zones which are needed to support and stabilize the flames inaircraft combustors. To process PIV data， I used DaVis 7.2 from LaVision. To the right is an example of abatch window. Included is an operation list window in which l adjusted the PIV，postproccessing， and vector field statistics settings to obtain the velocity and RMSdata. References Acknowledgements Thank you to Dr. Yolanda Hicks， who mentored me andguided me with the technical aspects of the processing.Thank you also to Bob Anderson， who assisted me innetworking four computers together to process the PIVdata. My deepest thanks to the coordinators of the MUSTProgram， without whom I would not have had thisopportunity to work at the Glenn Research Center.