This study discusses the components' geometry and its effect on the capability of heat transmission and pressure drop because of its evident influence on the performance of micro capillary pumped loop (MCPL). On analyzing the dimensional effect on heat transmission and pressure gradient of MCPL device, some results were yielded and addressed as follows: The vapor line was the most important factor among the components of MCPL in heat transmission and pressure drop. Furthermore, the depth of vapor line was the main parameter because of its drastic effect. In addition, at depth of vapor line, hv, ranging from 20 μm to 150 μm, the amount of heat transferred for system will increase, but decrease the pressure drop. However, for hv larger than 150 μm, the heat transfer and pressure drop both will reach a limit. A new family of geometrical dimensions of MCPL possessing an excellent heat flux of 178 W/cm2 would be obtained. These findings will be useful in designing a better MCPL.
