Enhancement of Nucleate Boiling on Rough and Dimpled Surfaces with Application to Composite Spreaders for Microprocessors Immersion Cooling
type: CreativeWork
description: Microprocessors have substantially increased total power dissipation and transistors density over the past two decades, owing to the growth in complexity, performance, and parallelism of computational systems. To continue to effectively and safely dissipate larger amounts of power, advanced methods of cooling such as immersion cooling by nucleate boiling of dielectric liquids are being considered. For electronic cooling applications, dielectric liquids are chemically inert, environmentally friendly, and have low saturation temperatures (34 — 56oC at 0.1 MPa) advantageous for keeping the chips junction temperature below that recommended by the manufacturer (85 — 115 oC), depending on the application. This research experimentally investigated the enhancement of pool nucleate boiling of PF-5060 dielectric liquid on uniformly heated, 10 x 10 x 1.6 mm rough and dimpled Cu surfaces. Fabricating these surfaces is cost effective and scalable, making them suitable for immersion nucleate boiling cooling of high powered microprocessors requiring heat spreaders of different sizes. The PF-5060 has a saturation temperature of 51.4oC at ~0.085MPa — the local pressure in Albuquerque NM, where the experiments were carried out. Because various circuit board orientations and the perpendicular mounting of add-in cards such as graphics processing units results in chip orientations that vary from 0o — 180o with respect to gravity, the effects of these surface inclinations on nucleate boiling of saturated and subcooled PF-5060, are thoroughly investigated for both the rough and dimpled Cu surfaces. In the experiments, liquid subcooling was varied up to 30 K. Experimental nucleate boiling heat transfer coefficient curves for rough Cu surfaces were used to computationally investigate the performance of composite spreaders. These spreaders removed the thermal power dissipated by a 20 x 20 mm microprocessor with and without hot spots, by saturation nucleate boiling of PF-5060. To ensure the c…
abstract: Microprocessors have substantially increased total power dissipation and transistors density over the past two decades, owing to the growth in complexity, performance, and parallelism of computational systems. To continue to effectively and safely dissipate larger amounts of power, advanced methods of cooling such as immersion cooling by nucleate boiling of dielectric liquids are being considered. For electronic cooling applications, dielectric liquids are chemically inert, environmentally friendly, and have low saturation temperatures (34 — 56oC at 0.1 MPa) advantageous for keeping the chips junction temperature below that recommended by the manufacturer (85 — 115 oC), depending on the application. This research experimentally investigated the enhancement of pool nucleate boiling of PF-5060 dielectric liquid on uniformly heated, 10 x 10 x 1.6 mm rough and dimpled Cu surfaces. Fabricating these surfaces is cost effective and scalable, making them suitable for immersion nucleate boiling cooling of high powered microprocessors requiring heat spreaders of different sizes. The PF-5060 has a saturation temperature of 51.4oC at ~0.085MPa — the local pressure in Albuquerque NM, where the experiments were carried out. Because various circuit board orientations and the perpendicular mounting of add-in cards such as graphics processing units results in chip orientations that vary from 0o — 180o with respect to gravity, the effects of these surface inclinations on nucleate boiling of saturated and subcooled PF-5060, are thoroughly investigated for both the rough and dimpled Cu surfaces. In the experiments, liquid subcooling was varied up to 30 K. Experimental nucleate boiling heat transfer coefficient curves for rough Cu surfaces were used to computationally investigate the performance of composite spreaders. These spreaders removed the thermal power dissipated by a 20 x 20 mm microprocessor with and without hot spots, by saturation nucleate boiling of PF-5060. To ensure the c…
author: Suszko, Arthur
language: English
keywords: Enhancement of nucleate boiling, dielectric liquids, immersion cooling, thermally anistropic composite heat spreasders, electronics cooling, thermal management, electronics packaging
date published: 2015-09-01T07:00:00Z
date modified: 2026-07-24T05:27:04Z
provider: University of New Mexico
publisher: Networked Digital Library of Theses and Dissertations
type: WebPage
source organization: University of New Mexico

PropertyValue
property ID: Handle
value: http://hdl.handle.net/1928/30421