In 1984, the concept of a micro heat pipe was first proposed by Cotter. Since that time, many investigators have conducted analytical and experimental investigations. Micro heat pipes ranging in size from 1 mm in diameter and 60 mm in length to 30 ㎛ in diameter and 10 mm in length have analyzed, modeled, and fabricated. In the present work, the heat transfer and fluid flow phenomena of in the micro heat pipe with curved triangular grooves are studied using both numerical and experimental methods. In the numerical part, a one-dimensional mathematical model for the micro heat pipe with curved triangular grooves is developed and solved to obtain the maximum heat transport rate, the capillary radius distribution, the liquid, and the vapor pressure distributions along the axial direction of the micro heat pipe under the steady-state condition. In particular, the modified Shah method is proposed to calculate the pressure drop induced by the liquid-vapor interfacial shear stress. Experimental investigations are conducted to validate the numerical model. In these experiments, the micro heat pipe with 0.56 mm in hydraulic diameter and 50 mm in length is tested and the surface temperatures at the wall of the micro heat pipe with curved triangular grooves are measured by thermocouples, when the operating temperature varies from 40℃ to 70℃ with an increment of 10℃. The maximum heat transport rate based on experimental results agrees well with the results of the numerical investigations. Finally, thermal optimization for geometry of the micro heat pipe with curved triangular grooves is performed using the numerical model.
