带射流的收缩型通道内部换热特性液晶瞬态实验

将航空发动机进气道支板冲击腔简化和放大为一带射流的收缩型通道,并采用最新窄带热色液晶全表面瞬态测温技术对其内表面进行冲击换热实验,具体研究了射流雷诺数、孔径及孔间距变化对努赛尔数分布及大小的影响。实验结果表明:射流雷诺数的增大、孔径的增大及孔间距的减少均使通道内部换热得以加强,但努赛尔数分布的变化及平均努赛尔数的增幅不尽相同;并且侧壁换热受孔间距影响最大,前缘换热则受射流雷诺数的影响最大。

Internal Heat Transfer Experiment with Liquid Crystal Transient Technique in Contraction Channel with Jet

A new type transient measurement technique using a narrow-band thermochromic liquid crystal (TLC) is employed to carry out a heat transfer experiment in a contraction channel, which is set up by predigesting and magnifying the strut in the inlet of an aeroengine. The effect of the Reynolds number, diameter and spacing of impingement holes on Nusselt number distribution and magnitude on the inner surfaces of the channel is studied. The results show that heat transfer of every inner surface is strengthened with the increase of the Reynolds number and the diameter, or the decrease of spacing, while the distribution of Nusselt numbers and the increase of mean Nusselt numbers are varied. In addition, the primary factor dominating the heat transfer on the side walls is spacing, but for the leading edge it is the Reynolds number.