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以最新微电子设备冷却剂ＦＣ－７２为工质，实验研究了自由和浸没情况下，圆形射流冲击５ｍｍ×５ｍｍ模拟电子芯片的局部对流换热情况。喷嘴直径ｄ＝０．９８７ｍｍ，Ｒｅ数范围为３４８８～４２６４４。测定了自由和侵没情况下驻点换热及换热系数的径向分布，讨论了雷诺数、喷嘴一传热面间距的影响。首次发现ＦＣ—７２自由射流在高Ｒｅ数下，随着喷射间距的增加，驻点换热得到加强，而浸没射流随喷射间距的增大，驻点换热出现非单调性变化；给出了喷射间距ｚ／ｄ＝４时驻点换热系数的关联式，并与其它工质的已有结果进行了比较；对换热系数径向分布的研究表明，与自由射流不同，浸没射流分布曲线上明显出现由层流向湍流过渡所引起的二次峰值。
With the latest microelectronic device coolant FC-72 as the working fluid, the local convective heat transfer of a circular jet impinging on a 5mm × 5mm analogue electronic chip under free and immersion conditions was experimentally studied. Nozzle diameter d = 0.987mm, Re number range of 3488 ~ 42644. The radial distribution of stagnation heat exchange and heat transfer coefficient under free and invaded conditions was measured. The influence of Reynolds number and nozzle-heat transfer surface spacing was discussed. For the first time, it was found that at high Reynolds number, the heat transfer of stagnation point was enhanced with the increase of jet spacing, while the change of jet heat transfer was stagnant with the increase of jet spacing. The correlation coefficient of stagnation point heat transfer coefficient at jet spacing z / d = 4 is compared with the existing results of other working fluids. The study on the radial distribution of heat transfer coefficient shows that, unlike the free jet, the submerged jet distribution curve On the apparent emergence of the transition from laminar to turbulent secondary peak.