环路热管失效后再启动特性实验

当环路热管所承受的瞬时热负载过大或蒸发器局部过热时，会出现失效现象。为使失效后的环路热管快速恢复正常工作状态，通过实验研究了两种环路热管失效后再启动方法的可行性以及影响环路热管再启动速度的因素。实验发现，在环路热管失效后的恢复过程中选择适当时机加热蒸发器，可使环路热管重新启动并缩短恢复时间；重力与加热功率是影响再启动速度的关键因素。加热功率较小时，重力辅助下的环路热管再启动速度明显快于逆重力状态下的环路热管；随着加热功率的提升，重力因素对环路热管再启动速度的影响逐渐减弱。环路热管失效后不切断热负载，通过抬高冷凝器的方式也可使环路热管停止失效，但此方法会导致环路热管出现逆流现象，因此不具备可行性。

Experiment on restart character of loop heat pipe after failure

When the instantaneous thermal load is too large or the partial overheating occurs in the evaporator, loop heat pipe is prone to failure. In order to make the failing loop heat pipe back to proper functioning as early as possible, the feasibility of two restart schemes after loop heat pipe fail and the factors affecting restarting speed were researched. The experimental results shows that reheating evaporator in the recover process after failure makes loop heat pipe restart to reduce recover time. Gravity and heating power are the key factors affecting restart speed. When the heating power is small, the restart speed under gravity assistance is much faster than the restart speed under antigravity. With the increasing of the heating power, effect of gravity factor on restart speed of loop heat pipe diminishes gradually. Loop heat pipe can also stop failure by lifting the condenser without cutting the heating power off. However, this scheme is not feasible because the reverse flow occurs in loop heat pipe.