对电子芯片在FC-72工质中浸没喷射沸腾换热进行了实验研究。通过干腐蚀技术在硅片表面加工出交错排列的柱状微结构(30μm×60νm,50μm×60μm,50μm×120μm,30νm×120μ1,宽×高),硅片尺寸为10 mm×10mm×0.5 mm,过冷度为35 K,喷射速度V分别为0.5,1,1.5 m/s。喷嘴数目分别为1,4和9,直径分别为3,1.5和1mm。喷嘴出口到芯片表面的距离分别为3,6和9 mm。实验表明,交错排列柱状微结构的换热效果要好于光滑芯片,临界热流密度随着喷射速度的增加而增加。在雷诺数及其他工况相同的情况下,不同喷嘴数目对换热的影响不同,当n=4时,所有芯片的壁面温度最低,临界热流密度最高,其次是n=9,换热效果最差的是n=1。在雷诺数及其他工况相同的情况下,所有芯片的换热性能在喷射距离s=3 mm时最好,其壁温最低,临界热流密度最高,随着喷射距离的增加,其壁面温度逐渐升高,临界热流密度逐渐减小。
The experiment was made of boiling heat transfer of FC-72 on staggered micro-pin-finned chips with submerged jet impingement. The dimension of the silicon chips is 10 mm×10 mm×0.5 mm (length x width x thickness) on which staggered micro-pin-fins with the four dimensions (width ×thickness x height, 50μm×50μm×60μm, 30μm×30μm × 60μm, 50μm×50μm×120μm and 30 μm×30 μm × 120μm, named S-PF50-60, S-PF30-60, S-PF50-120, S-PF30-120) were fabricated by using the dry etching technique. The effects of jet velocity(Vj = 0.5, 1, 1.5 m/s), nozzle numbers (n = 1, 4, 9), jet-to-target distance (s = 3, 6, 9 mm), and micro-pin-fins on jet impingement boiling heat transfer were explored. The results showed that staggered micro-pin-fins show better heat transfer performance compared with smooth surface. The critical heat flux increases linearly as jet velocity increases. At a fixed Reynolds number, all chips at nozzle number n = 4 show the lower wall temperature and higher CHF than that at n = 1 andn= 9, and at n = 1, all chips show the worst heat transfer performance. Small nozzle-to-surface dis- tance, s = 3 mm, shows a little better heat transfer performance than that of s = 6 mm and s = 9 mm.