Using water as working medium

an experimental investigation on heat transfer performance of the nickel foam wick heat pipe and the mesh wick heat pipe was conducted under the conditions of natural cooling and water cooling.The wall temperature distribution and isothermal characteristic of the two heat pipes were discussed.The variation of the evaporation and condensation heat transfer coefficients in the nickel foam wick heat pipe with the heat flux with natural cooling were obtained.In a certain range

the evaporation and condensation heat transfer coefficients increased with the increase of the heat flux.Under the conditions of water cooling

the evaporation heat transfer coefficients in the nickel foam wick heat pipe first increased and then decreased with the increase of the heat flux when the cooling water flow rate was 0.01 m3穐-1.The experimental results indicate that the nickel foam wick heat pipe has a good start-up performance

and the mesh wick heat pipe is easier to reach the heat transfer limit than the nickel foam wick heat pipe.