In this study, the effect of oscillation amplitude on the pulsed impinging jets in different nozzle to surface distances and Reynolds numbers investigated. Generally, the heat transfer increases by increasing frequency and amplitude. For distances smaller and longer than the length of the jet potential core the threshold frequency is highly dependent on the amplitude. As the amplitude increases, the threshold Strouhal number decreases, while for nozzle to surface distance near the end of the jet core the threshold Strouhal number is approximately independent from the oscillation amplitude and the Reynolds number and is about $Sr\approx 0.041.$ Also, although increasing the Reynolds number causes an enhancement in the threshold frequency, but in smaller amplitudes the heat transfer, increased relative to the corresponding steady jet.

在这项研究中，研究了振荡振幅对不同喷嘴中脉冲冲击射流对表面距离和雷诺数的影响。通常，热传递通过增加频率和幅度而增加。对于小于和大于喷射电势芯的长度的距离，阈值频率高度依赖于振幅。随着振幅的增加，阈值Strouhal数减小，而对于喷嘴到射流核心末端附近的表面距离，阈值Strouhal数大约与振荡幅度和雷诺数无关，大约为$\mathrm{小号}\mathrm{[R}\approx 0。041。$ 同样，尽管增加雷诺数会导致阈值频率的增加，但是在较小的振幅下，传热相对于相应的稳定射流会增加。