Fluid-Dynamic Diagnostics on interior flow patterns of Heat Sink Using PIV system

• Main Authors: Jyun-Hong Chen, 陳俊宏
• Other Authors: Herchang Ay
• Format: Others
• Language: zh-TW
• Published: 2006
• Online Access: http://ndltd.ncl.edu.tw/handle/14093337019064573372

碩士 === 國立高雄應用科技大學 === 模具工程系碩士班 === 94 === As technology advances, many products move towards electrification. Heat transfer is very important in the electronic industry. The finned heat sink is the most convenient and economic way of cooling. This research uses the Particle Image Velocimetry System－a non-invasive method that measures the interior flow patterns of the plate-finned and pin-finned heat sink. Different fan sizes were used along with two different flow types; for example, blow-out and draw-in. By changing the rotation speed of the fan, we can see the impact using a computer cooling fan. The test results using the plate-finned heat sink showed that it was influenced by the axis of the fan. Different interior flow patterns appeared in each section. Comparing the draw-in and blow-out airflow of a fan, the vortex produced is less when the air is drawn in than when the air is blown out. Because both sides of the outlet have different air volumes, using different cooling fan sizes produces more obvious results. The draw-in and blow-out air flows of the fan produces different results. The study found a large vortex near the center of the base for when using the blow-out function. To improve the cooling effects, the cold air draw-in the plate-fin heat sink is the best choice. This conclusion is also confirmed by infrared thermography. Because the geometry and size of the pin-finned heat sink is different from the plate-finned heat sink, the vortex was not obvious when measured under the same conditions. The PIV system was used to produce a diagram of the import and export velocity contours. This information was used to estimate the flow volumes for each section by comparing to the inlet size. The geometry of the fan has a large influence on the entering air flow volumes.