Numerical analysis and experimental verification on thermal fluid phenomena in a vapor chamber

A numerical analysis is carried out on a flat-plate type heat pipe called “vapor chamber”. The vapor chamber is an advanced cooling heat spreader for high-performance microchips, such as new generation CPUs in personal computers and workstations. The mathematical model of the vapor chamber formulated in this study is a two-phase closed disk-shaped chamber and is placed between a small heat source and a large heat sink. Wick sheets and a wick column are provided inside the vapor chamber to circulate the working fluid. By solving the equations of continuity, momentum and energy numerically, the velocity, pressure and temperature distributions inside the vapor chamber are obtained. From the numerical results, the capillary pressure head necessary to circulate the working fluid is estimated and the temperature drop inside the vapor chamber is determined. These numerical results are useful for the design and improvement of the vapor chamber. Experimental investigation is also carried out, and fairly good agreement is obtained with the numerical results, which confirms the validity of the present numerical analysis.