| 摘要 |
<P>PROBLEM TO BE SOLVED: To prevent a heat pipe from being dried out or failed by adjusting the capillarity pressure of a wick after assembly. <P>SOLUTION: The layers 105 and 107 of the heat pipe 100 using a multi-layer shape memory alloy (SMA) as a wick structure have different transformation temperatures. When a heat is applied to the heat pipe 100 along the surface thereof, first the inner layer 105 of the SMA is started to shrink. By that shrinkage, the effective capillary radius r<SB>c</SB>of the wick is reduced, and the pump pressure of the capillary 108 and, accordingly, a capacity to remove heat are maintained or increased. When the temperature of the heat pipe 100 continues to rise, the outer layer 107 is started to shrink since the capillary radius r<SB>c</SB>is further reduced. As a result, a local pump pressure is maintained or matches a higher local heat flux and increased to remove the heat to prevent 'dry out'. <P>COPYRIGHT: (C)2003,JPO |
