Thermosyphon Boiling in Vertical Channels

Abstract

The high heat flux capability and modest temperature differences associated with boiling heat transfer make immersion cooling one of the primary candidates for VHSIC and VLSI microelectronic component thermal control. While the literature contains many references to pool boiling heat transfer from single integrated circuit packages or transistor cans, there is as yet little information on ebullient thermal transport from vertical arrays of parallel, densely packaged Printed Circuit Boards or ceramic modules. The present study represents an attempt to explore the thermal performance of such ebullient cooling systems by analytically and empirically investigating boiling heat transfer in water from a pair of flat, isoflux plates. Experimental results for wall temperature as a function of axial location, heat flux, and plate spacing are presented. A theoretical model for liquid flow rate through the channel is developed and used as a basis for correlating the rate of heat transfer from the channel walls.