Theoretical Reserch On Micro Flat Heat Pipe With Silicon On Glass Structure

Theoretical analysis and numerical simulation of SOG structure micro flat heat pipe are presented in this paper. Micro heat pipes have very high heat conductivity by the phase changes of its working fluid without needs for extra power. For the advantages of micro heat pipes, they are used in a lot of areas such as the cooling of chips, electronic components, and electronic systems and so on.Larger power and smaller area of a chip lead to very high power density in an electronic chip. Heat generated in the chip might strongly affect the function and stability of the chip if the heat isn't dissipated efficiently and immediately. Traditional ways of heat dissipation no longer match the high power density condition and micro heat pipe technique becomes the most appropriate way to solve this problem.Since Cotter introduced the definition of micro heat pipe, some one-dimensional steady-state mathematical models for micro heat pipe with different groove shapes were established. But the parameters and definitions are not very clear in the previous models and the shear stress between vapor and fluid was not considered which result in imprecise of these models. Account for the disadvantages mentioned above, improvements are done to establish a one-dimensional mathematical model for micro heat pipe in this paper. Parameters in the model are clarified and the influences of vapor shear stress on the heat transport performance are considered more precisely. Maximum heat transport capacity of micro heat pipe is calculated in addition. The results predicted by the model are compared with the published results in literature and show good agreement. The best hydraulic diameter and the best groove width are also obtained to direct the micro heat pipe design. Besides, the operation limits of micro heat pipe are analyzed and calculated to direct the design of MHP.