Hotspot Cooling Performance of a Submerged Water Jet via Infrared Thermometry
Hotspot Cooling Performance of a Submerged Water Jet via Infrared Thermometry
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DOI：
10.1109/itherm45881.2020.9190595
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发表时间：
2020-07
期刊：
影响因子：
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通讯作者：
T. Chowdhury;C. Brewer;S. Putnam
中科院分区：
文献类型：
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作者：
T. Chowdhury;C. Brewer;S. Putnam
液体射流冲击是微电子技术中消除局部热锅效应最有效的方法之一。由于射流冲击冷却具有垂直入射的流场，其减薄滞止区局部热边界层的能力使其传热系数接近1 MW/m2·K。本实验研究提出了水射流冲击冷却的激光加热铪（Hf）薄膜在玻璃上的HTC数据。激光二极管在稳态或脉冲激光工作模式下诱导局部热点。热点的面积在0.04 mm 2至0.2 mm 2之间，热通量高达1.35 MW/m2。浸没式射流冲击结构采用进口射流直径为1.2 mm，喷嘴到热点/表面距离为1.3 mm，射流雷诺数为1.24 2004。HTCs使用红外（IR）测温法测量，使用1.5-5 µm光谱分辨率FLIR相机。还研究了相对于射流/壁面驻点和局部热点中心之间的偏移的HTC的空间依赖性。例如，对于与热点中心共对准的冲击射流，对于稳定和脉冲调制激光加热（分别）测量到的HTCs为1050 kW/m2·K和10470 kW/m2·K，而对于偏移超过106 mm（x/D >5），测量到的HTCs <100 kW/m2·K。
Liquid jet impingement is one of the most effective methods for dissipating local hotpot heat fluxes in microelectronics. Due to its normal incident flow-field, jet impingement cooling can achieve heat transfer coefficients (HTCs) approaching ≈1 MW/m2•K due to its ability to thin the local thermal boundary layer in the stagnation region. This experimental study presents HTC data for water jet impingement cooling of a laser heated Hafnium (Hf) thin-film on glass. A laser diode induces local hotspots for either a steady- or pulsed-laser operation mode. The hotspots have areas ranging within 0.04 mm2 to 0.2 mm2 and heat fluxes up to ≈3.5 MW/m2. A submerged jet impingement configuration is pursued with an inlet jet diameter of ∼1.2 mm, jet nozzle to hotspot/surface distance of ∼3.2 mm, and the jet Reynolds Number of ∼2004. The HTCs are measured using infrared (IR) thermometry using a 1.5-5 µm spectral resolution FLIR camera. Also investigated is the spatial dependence of the HTC relative to the offset between jet/wall stagnation point and the center of the local hotspot. For example, for impinging jets that are co-aligned with the hotspot center, HTCs of ∼650 kW/m2•K and ∼470 kW/m2•K are measured for steady and pulsed-modulated laser heating (respectively), whereas, for offsets beyond ∼6 mm (x/D >5), the measured HTCs are <100 kW/m2•K.