Effective cooling way is required to cool the electronic devices with small space and high heat flux. Mini-grooved flat heat pipe with simple structure, high thermal conductivity and good temperature uniformity meets the requirement of electronic devices rapidly cooling. A visualization experiment was established in this paper to study the fluid flow and heat transfer performance of the mini-grooved flat heat pipe. The fluid flow and distribution were clearly observed in the visualization experiment. It was found that the flat heat pipe had better thermal characteristics than copper and obviously affected by the input heat and filling working fluid type. And the heat pipe filled with deionized water possessed better thermal conductivity and heat transfer limit than that filled with anhydrous ethanol or hexane, while the lower hydrophilic performance of deionized water with copper weakened the temperature uniformity of the heat pipe filled with deionized water compared those of anhydrous ethanol and hexane. In this way, all kinds of factors need to be consider to select the working fluid of the heat pipe for electronic devices cooling.
Keywords Flat heat pipe, Experiment, Visualization, Working fluid, Evaluation parameter