摘要
对旋进射流冲击平板时的传热进行了实验研究。通过在圆筒套管内设置一块孔板构成旋进射流喷嘴,得到了持续稳定的旋进射流。对旋进射流的流动特性作了研究,给出了旋进射流的频率与尺寸、Re的关系。用两种不同孔径的旋进射流冲击一块加热平板,并与普通的射流冲击传热作对比。结果表明,由于旋进射流与流体混合作用加剧而大大地降低了流速,使得强化传热的效果减弱,这种趋势在驻点附近尤为明显。
Heat transfer under precessing impinging jet was experimentally studied. A self-sustained uninterrupted precession motion was generated in a precessing jet nozzle consisting of a cylindrical tube added to an orifice. The precession frequency of the jet was identified from a power spectrum density analysis to the velocity data measured by a hot wire. The influences of the nozzle diameter and Reynolds number on precession frequency were studied. The heat transfer behavior of precessing jet impinging was compared with that of in-line impinging jet. The results indicate that heat transfer coefficients under precessing jet impinging decrease because the jet velocity is decreased by an ambient air entrainment.
出处
《热科学与技术》
CAS
CSCD
2007年第1期51-55,共5页
Journal of Thermal Science and Technology
基金
国家自然科学基金资助项目(50676088)
浙江省自然科学基金资助项目(Y105679)
教育部留学回国人员科研启动基金资助项目([2005]383)
关键词
旋进射流
冲击
强化传热
precessing jet
impinging
heat transfer enhancement
