Use of a thin liquid film moving under the action of gas flow in a mini-channel for removing high heat fluxes

Dmitry Zaitsev,Evgeniy Orlik,Egor Tkachenko,Oleg Kabov

doi:10.1051/matecconf/201792010037

Abstract

Intensively evaporating liquid films shear-driven in a mini- or micro-channel under the action of cocurrent gas flow are promising for the use in modern cooling systems of semiconductor devices. In this work, we investigated the influence of liquid and gas flow rates on the critical heat flux in a locally heated film of water, moving under the action of air flow in a mini-channel. In experiments a record value of critical heat flux of 870 W/cm2 was reached. Heat spreading into the substrate and heat losses to the atmosphere in total do not exceed 25 % at heat fluxes above 400 W/cm 2 . A comparison with the critical heat flux for water flow boiling in the channel shows that, for shear-driven liquid films the critical heat flux is almost an order of magnitude higher.

Highlights

The development of modern microelectronic equipment requires efficient cooling systems, as it is necessary to remove high heat fluxes, up to 1 kW/cm2, from local areas of the processor [1]
First experiments with shear-driven liquid films showed that such films are less prone to thermocapillary rupture than the ones moving under the action of gravity. This is because the film rupture and the formation of dry spots can be controlled by the gas flow
In works [6,7] it is found, that in two phase flows in rectangular channels the stratified flow sub-regime, when a very thin liquid film is moving along the channel walls under the action of cocurrent gas flow, can exist for the channel heights as small as 100 μm and less

Summary

Introduction

The development of modern microelectronic equipment requires efficient cooling systems, as it is necessary to remove high heat fluxes, up to 1 kW/cm, from local areas of the processor [1]. First experiments with shear-driven liquid films showed that such films are less prone to thermocapillary rupture than the ones moving under the action of gravity This is because the film rupture and the formation of dry spots can be controlled by the gas flow. Authors of [8] propose an efficient way of reduction of the viscous resistance in two-phase flows in micro-channels. All these studies confirm the prospects of using shear-driven liquid films for cooling of microsystems with high heat generation. The present paper presents new experimental data proving that shear-driven liquid films are capable to remove heat fluxes as high as 870 W/cm from a heat source of 1x1 cm

Methods

Results

Conclusion