Heat transfer characteristics of flat plate heat pipe

Abstract

The purpose of this study was to explore the heat transfer characteristics of flat plate heat pipes (FPHPs) The four parameters examined in this study were the liquid filling ratios length bending angles and tilting; their effects on the heat transfer characteristics were examined experimentally All the FPHPs were made of Al 6061 FPHPs which were filled with acetone (99 87% pure) The results showed that optimum liquid filling ratios Fr exhibited by the effective thermal resistance Rth(min) were 20 1% 24 8% 31 4% and 35 1% for the length of 80 mm 150 mm 200 mm and 300 mm respectively The effective thermal resistance Rth(min) ratios normalized by that of 80 mm FPHP were 2 4 6 0 and 17 9 for lengths of 150 mm 200 mm and 300 mm respectively The maximum heat transport capability Qmax decreased greatly from 109 5 W to 49 6 W when length was increased from 80mm to 150 mm and then slowly decreased further to the minimum value of 35 W when the length was 300 mm For the bending angle β from 0° to 90° the maximum effective thermal conductivity Keff(max) increased from 1933W/mK to 6365W/mK and the maximum heat transport capability Qmax increased from 45 W to 85 W For the tilting angle θ from 0° to 90° Keff(max) increased from 4561 W/mK to 5530 W/mK; whereas Rth(min) reduced from 0 22 W/K to 0 182 W/K And the maximum heat transport capability Qmax increased from 39 7 W to 130 W On the other hand by tilting from 0° to -30° the maximum heat transport capability Qmax reduced drastically to 3 W That is by the proper liquid filling ratio length bending angle and tilting angle cooling enhancement of the FPHPs could be greatly achieved

Date of Award	2015 Jul 29
Original language	English
Supervisor	Jung-Hua Chou (Supervisor)