Experimental study on start-up and steady-state heat transfer performance of heat pipe with liquid bypass line for accelerating working fluid

Research on the Manufacturing Process and Heat Transfer Performance of Ultra-Thin Heat Pipes: A Review

“…The thermal resistance is only increased by 40% under six times the thickness of the wick, and the six-layer wire mesh greatly improves the maximum heat transfer capacity of the heat pipe [ 95 ]. In order to reduce the thermal resistance of the heat pipe, as shown in the Figure 20 d [ 96 ], Baek et al added an auxiliary pipe from the condensation end to the evaporation end on the basis of the conventional heat pipe to facilitate the return of the condensate to the evaporation end. When the heat pipe is placed horizontally, the thermal resistance of NOM (auxiliary channel off) is very close to the standard heat pipe of the same specification, but the thermal resistance of BOM (auxiliary channel on) is significantly smaller than that of NOM, which confirms the positive effect of developing auxiliary pipes on the performance of heat pipes [ 96 ].…”

“… Different optimized designs: ( a ) schematic diagram of the spiral coil heat pipe structure and its application design [ 93 ]; ( b ) the relationship between heat flux, optimal wick permeability and effective thermal conductivity, heat flux, optimal wick thickness, as well as the relationship between the relevant pressure drop, heat flux, ratio of optimal evaporator length to condenser length ( Le/Lc ), and optimal wick permeability ( K ) and wick thickness ( t wick ) [ 94 ]; ( c ) the effect of the number of layers of wire mesh on the heat transfer rate of the heat pipe in the horizontal direction [ 95 ]; ( d ) The operation diagram of the heat pipe with auxiliary pipes, the thermal resistance comparison of standard heat pipe, NOM, and BOM, where R HP is heat pipe thermal resistance, R Sys is system thermal resistance [ 96 ]; ( e ) schematic diagram of the combination of heat pipe and spray cooling [ 98 ]. …”