フィン間狭あい流路内強制流動沸騰を利用した高熱流束・ 大面積冷却システムの研究開発（重力方向の影響）

抄録

Cooling technology becomes more important by the increase of heat generation density from semiconductors densely integrated. Boiling two-phase flow is one of the effective methods because of its high heat removal ability. When two-phase flow is used under microgravity conditions, it gives valuable information to clarify the effect of gravitational direction on ground. The cooling system by using flow boiling in fin spacing narrow channels is developed for practical application of large area cooling under high heat flux conditions. The cooling system realizes the increase in critical heat flux by an enlarged heating area of fin structures and increase in heat transfer coefficient by the evaporation of thin liquid film underneath sliding bubbles generated between fins. To evaluate the cooling performance, flow boiling experiments are conducted by using water under low pressure conditions. A narrow channel with heating length of 100mm and with fin geometries of thickness 1mm, height 10mm and gap size 2mm is employed. Its nominal heating area without fins is 30mm×100mm. To understand the effect of gravitational direction, channel inclination angle is varied to test the upward flow for upward-facing and downward-facing heating surfaces. Key Words: Flow boiling, Narrow channel, Heat transfer, Gravity, Orientation