In order to suffice the different needs for pore size and thermal conductivity of wick in different evaporator regions of loop heat pipe (LHP)

a LHP with modulated composite porous wick is constructed and investigated experimentally. The heat transfer characteristics of LHP are tested at different heating powers

inclination angles and cooling conditions. The results show that LHP has good heat transfer performances. The lowest temperature of the evaporator wall center (Tc) is only 64℃ at 200 W. The ice cooling can significantly promote LHP heat transfer performance

reducing Tc and thermal resistance

compared with the air cooling. The lowest thermal resistance is 0.19 K·W-1. Besides

the ice cooling is helpful to improving the temperature uniformity of the evaporator wall. The effects of inclination angles on temperature and thermal resistance vary with the increase of the heating power. At low heating power

Tc of LHP with evaporator and condenser being the same altitude is lower than that with evaporator below condenser. As the heating power rises

the former becomes higher than the latter. In addition

the heat leak from evaporator to compensation chamber can be reduced by applying the modulated composite porous wick. With the increase of heating power

the effects of inclination angles on heat leak are different.