摘要
Experimental study and numerical simulation were performed for the averaged flow field of two closely spaced opposed jets with hot wire anemometer(HWA)and CFD software and the simulation was compared with the measurement and approximate analytic solution in the literature.The results showed that the exit velocity profile of the single jet was top-hat distribution due to the presence of boundary layers.At L<2D(where L is nozzle separation and D is nozzle diameter),bimodal distribution of exit velocity profile,low in the middle and high on both sides,was present,while such bimodal distribution of exit velocity profile was absent at L=2D.With increasing nozzle separation,the stagnation point offset of the impinging plane increased.With the same velocity ratio,stagnation point offset of the nozzles with uniform profiles was larger than that with top-hat profiles.The approximate analytic solution of the flow field of two opposed jets in the literature was only valid for the nozzles with uniform exit velocity profiles and the prediction accuracy became worse for the nozzles with top-hat exit velocity profiles.
Experimental study and numerical simulation were performed for the averaged flow field of two closely spaced opposed jets with hot wire anemometer (HWA) and CFD software and the simulation was compared with the measurement and approximate analytic solution in the literature. The results showed that the exit velocity profile of the single jet was top-hat distribution due to the presence of boundary layers. At L〈2D (where L is nozzle separation and D is nozzle diameter), bimodal distribution of exit velocity profile, low in the middle and high on both sides, was present, while such bimodal distribution of exit velocity profile was absent at L=2D. With increasing nozzle separation, the stagnation point offset of the impinging plane increased. With the same velocity ratio, stagnation point offset of the nozzles with uniform profiles was larger than that with top-hat profiles. The approximate analytic solution of the flow field of two opposed jets in the literature was only valid for the nozzles with uniform exit velocity profiles and the prediction accuracy became worse for the nozzles with top-hat exit velocity profiles.
出处
《化工学报》
EI
CAS
CSCD
北大核心
2007年第6期1385-1390,共6页
CIESC Journal
基金
教育部新世纪人才支持计划项目(NCET-05-0413)
国家重点基础研究发展计划项目(2004CB217703)。~~
关键词
两喷嘴对置撞击流
小喷嘴间距
驻点偏移
出口速度分布
two opposed jets
close nozzle separation
stagnation point offset
exit velocity profile