The high-speed oil-filled ball spinning and drawing process was put forward to manufacture the axially grooved heat pipe with highly efficient heat-transfer performance,and the forming mechanism of micro-grooves insid...The high-speed oil-filled ball spinning and drawing process was put forward to manufacture the axially grooved heat pipe with highly efficient heat-transfer performance,and the forming mechanism of micro-grooves inside the pipe was investigated.The key factors influencing the configurations of micro-grooves were analyzed.When the spinning depth varies between 0.4 mm and 0.5 mm,drawing speed varies from 200 mm/min to 450 mm/min,rotary speed is beyond 6 000 r/min and working temperature is less than 50 ℃,the grooved tubes are formed with high quality and efficiency.The ball spinning process uses full oil-filling method to set up the steady dynamic oil-film that reduces the drawing force and improves the surface quality of grooved copper tube.展开更多
Separate type heat pipe heat exchangers are often used for large-scale heat exchanging. The arrangement of such a heat exchanger conveniently allows heat input to and output from the heat exchanger at remote locations...Separate type heat pipe heat exchangers are often used for large-scale heat exchanging. The arrangement of such a heat exchanger conveniently allows heat input to and output from the heat exchanger at remote locations. The traditional method of designing an ordinary HPHE (heat pipe heat exchanger) is commonly applied in the separate type exchanger design, but the calculations have to be carried out separately, which makes it very complicated. In this work, the ε-NTU (effectiveness-Number of Transfer Units) method was applied for optimization analysis of single- or multi-level separate type heat pipe heat exchangers. An optimizing formula for single-level separate type heat pipe heat exchangers was obtained. The optimizing principles of effec- tiveness-NTU and heat transfer rate by the equal distribution method for multi-level separate type heat pipe heat exchanger are presented. The design of separate type heat pipe heat exchangers by the optimizing method is more convenient and faster than by the traditional method.展开更多
2008年的盛夏,一款高端风冷新贵华硕狮子王(Lion Square)凭借8mm 直径纯铜热导管、纯铜底座、双面波浪形高密度全铝鳍片搭配9厘米 LED 风扇……成功为处理器降温30%,让玩家在盛夏酷暑轻松挑战180瓦的超频极限。而近期华硕再次倾献巨礼,...2008年的盛夏,一款高端风冷新贵华硕狮子王(Lion Square)凭借8mm 直径纯铜热导管、纯铜底座、双面波浪形高密度全铝鳍片搭配9厘米 LED 风扇……成功为处理器降温30%,让玩家在盛夏酷暑轻松挑战180瓦的超频极限。而近期华硕再次倾献巨礼,从即日起华硕狮子王(Lion Square)将在全国卖场进行大幅调价。展开更多
基金Projects(50705031, 50436010) supported by the National Natural Science Foundation of ChinaProject(KF0707) supported by the Open Foundation of the Key Laboratory of Enhanced Heat Transfer and Energy Conservation, Ministry of Education, ChinaProject (8151064101000058) supported by the Natural Science Foundation of Guangdong Province, China
文摘The high-speed oil-filled ball spinning and drawing process was put forward to manufacture the axially grooved heat pipe with highly efficient heat-transfer performance,and the forming mechanism of micro-grooves inside the pipe was investigated.The key factors influencing the configurations of micro-grooves were analyzed.When the spinning depth varies between 0.4 mm and 0.5 mm,drawing speed varies from 200 mm/min to 450 mm/min,rotary speed is beyond 6 000 r/min and working temperature is less than 50 ℃,the grooved tubes are formed with high quality and efficiency.The ball spinning process uses full oil-filling method to set up the steady dynamic oil-film that reduces the drawing force and improves the surface quality of grooved copper tube.
文摘Separate type heat pipe heat exchangers are often used for large-scale heat exchanging. The arrangement of such a heat exchanger conveniently allows heat input to and output from the heat exchanger at remote locations. The traditional method of designing an ordinary HPHE (heat pipe heat exchanger) is commonly applied in the separate type exchanger design, but the calculations have to be carried out separately, which makes it very complicated. In this work, the ε-NTU (effectiveness-Number of Transfer Units) method was applied for optimization analysis of single- or multi-level separate type heat pipe heat exchangers. An optimizing formula for single-level separate type heat pipe heat exchangers was obtained. The optimizing principles of effec- tiveness-NTU and heat transfer rate by the equal distribution method for multi-level separate type heat pipe heat exchanger are presented. The design of separate type heat pipe heat exchangers by the optimizing method is more convenient and faster than by the traditional method.
