STRAIN ANALYSIS OF VAPOR CHAMBER HEAT SPREADERS

Vapor chamber is a cooling device with phase change phenomena. It not only provides high heat transfer coefficient but also removes hot spot. During working of vapor chamber, the buckle force and vapor pressure could lead to deformation. It is a popular way that pillars are set up to reduce deformation. This paper presents a three-dimensional finite element analysis for the vapor chamber by ANSYS software program. Four pillars with two kinds of designs are built into vapor core in order to avoid deformation of the vapor chamber. The results appear that pillars inside vapor chamber are good to reduce strain up to 81-91%. The effects of thickness, materials, and heater sizes on the strain are discussed. The optimum pillar design can be obtained by cooperating with heater sizes, although the effective heat area may be possibly reduced. The results attained that the appropriate design of pillars could enhance structure performance of the vapor chamber.