Multiple loop heat pipe is a high-functional thermal transport device. This work was conducted to confirm the working performance of Multiple loop heat pipe under thermal vacuum ambience with the working fluid ammonia...Multiple loop heat pipe is a high-functional thermal transport device. This work was conducted to confirm the working performance of Multiple loop heat pipe under thermal vacuum ambience with the working fluid ammonia. Asmall multiple loop heat pipe with two evaporators and two ra- diators was designed and fabricated. Then thermal vacuum test was conducted. The heaters were fasten on both evaporators, both radiators, both compensation chambers. In the case that both evaporators were heated, the multiple loop heat pipe can transport 120/120 W for 1.5 m, in the case that only one evaporator was heated, evaporator 1 can transport 80 W for 1.5 m, while eva- porator 2 can transport 120 W for 1.5 m. Two flow regulators were installed near the confluence of liquid line to prevent uncondensed vapor penetrating into returning liquid when the tempera- ture difference exists between two radiators. In the case that the heat load at both evaporators were 40/40 W and one radiator was heated, the flow regulator1 can tolerate the 160 W of heat load which was supplied to radiator1 while the flow regulator2 can tolerate the 100 W of heat load which was supplied to radiator2. To demonstrate the multiple loop heat pipe’s startup behavior at lowheat load, each of the compensation chamber was preheated to change the initial distribution of liquid and vapor in the evaporator and compensation chamber, in the result, each evaporator can start up at 5W through preheating.展开更多
在金川矿山膏体充填系统开展了泵压管道输送特性环管试验,针对不添加水泥和胶砂比为1∶4的2种全尾砂膏体进行了管道输送阻力试验。结果表明,膏体输送平均流速为1.2 m/s时,质量浓度为72.2%,75.8%和78.9%的管输阻力分别为10,19和33 k Pa/m...在金川矿山膏体充填系统开展了泵压管道输送特性环管试验,针对不添加水泥和胶砂比为1∶4的2种全尾砂膏体进行了管道输送阻力试验。结果表明,膏体输送平均流速为1.2 m/s时,质量浓度为72.2%,75.8%和78.9%的管输阻力分别为10,19和33 k Pa/m;胶砂比为1∶4、质量浓度为78.9%的胶结全尾砂膏体管输阻力为12.5 k Pa/m。针对全尾砂与棒磨砂配比分别为6∶4、5∶5和4∶6的3种混合骨料,开展了膏体管输阻力试验,结果表明,在平均流速为1.2 m/s、管输阻力不大于15 k Pa/m的条件下,3种混合骨料膏体可泵送膏体质量浓度分别为80%,79%和81%;试验结果还显示,质量浓度相差1%,管道阻力损失相差50%~100%,可见膏体管输阻力对浓度变化十分敏感;3种配比的混合骨料膏体塌落度大于15 cm,满足膏体泵压输送要求。膏体减阻试验结果揭示,添加水泥材料1.5%的YNB型泵送剂,膏体管输减阻效率可达到68.6%,相应的膏体塌落度增加88%。展开更多
文摘Multiple loop heat pipe is a high-functional thermal transport device. This work was conducted to confirm the working performance of Multiple loop heat pipe under thermal vacuum ambience with the working fluid ammonia. Asmall multiple loop heat pipe with two evaporators and two ra- diators was designed and fabricated. Then thermal vacuum test was conducted. The heaters were fasten on both evaporators, both radiators, both compensation chambers. In the case that both evaporators were heated, the multiple loop heat pipe can transport 120/120 W for 1.5 m, in the case that only one evaporator was heated, evaporator 1 can transport 80 W for 1.5 m, while eva- porator 2 can transport 120 W for 1.5 m. Two flow regulators were installed near the confluence of liquid line to prevent uncondensed vapor penetrating into returning liquid when the tempera- ture difference exists between two radiators. In the case that the heat load at both evaporators were 40/40 W and one radiator was heated, the flow regulator1 can tolerate the 160 W of heat load which was supplied to radiator1 while the flow regulator2 can tolerate the 100 W of heat load which was supplied to radiator2. To demonstrate the multiple loop heat pipe’s startup behavior at lowheat load, each of the compensation chamber was preheated to change the initial distribution of liquid and vapor in the evaporator and compensation chamber, in the result, each evaporator can start up at 5W through preheating.
文摘在金川矿山膏体充填系统开展了泵压管道输送特性环管试验,针对不添加水泥和胶砂比为1∶4的2种全尾砂膏体进行了管道输送阻力试验。结果表明,膏体输送平均流速为1.2 m/s时,质量浓度为72.2%,75.8%和78.9%的管输阻力分别为10,19和33 k Pa/m;胶砂比为1∶4、质量浓度为78.9%的胶结全尾砂膏体管输阻力为12.5 k Pa/m。针对全尾砂与棒磨砂配比分别为6∶4、5∶5和4∶6的3种混合骨料,开展了膏体管输阻力试验,结果表明,在平均流速为1.2 m/s、管输阻力不大于15 k Pa/m的条件下,3种混合骨料膏体可泵送膏体质量浓度分别为80%,79%和81%;试验结果还显示,质量浓度相差1%,管道阻力损失相差50%~100%,可见膏体管输阻力对浓度变化十分敏感;3种配比的混合骨料膏体塌落度大于15 cm,满足膏体泵压输送要求。膏体减阻试验结果揭示,添加水泥材料1.5%的YNB型泵送剂,膏体管输减阻效率可达到68.6%,相应的膏体塌落度增加88%。
