Abstract

The miniaturization of electronic devices requires advanced thermal management techniques. The two-phase heat transfer process offers more effective and sustainable approach compared to the presently used single-phase cooling techniques. The boiling heat transfer is a two-phase cooling technique, that dissipates a high heat flux while maintaining the low surface temperature thereby, offering an efficient heat transfer mechanism compared to the single-phase process. Furthermore, the surface enhancement techniques such as micro/nano porous coatings help to maintain the low surface temperature thus improving the overall heat transfer performance. Electrodeposition is a simple technique that enhances this performance by creating the porous structure on the surface. This research focuses on developing an enhanced microscale structures on plain copper surfaces to improve the pool boiling performance. Additionally, the longevity (or the long-term stability) and aging of these enhanced structures, and their effects on the pool-boiling performance is also investigated.

Initially the pool boiling performance of enhanced surfaces is studied. The enhanced surfaces were prepared using electrodeposition of copper and graphene oxide. Later, the effects of repetitive boiling on the morphology of the surfaces were examined using various characterization techniques such as Scanning Electron Microscope (SEM), X-Ray Diffraction (XRD), and Fourier Transform Infrared (FTIR).

The chips coated with electrodeposition method rendered a high pool boiling performance for GS-4 (2.5% GO-Cu electrodeposited chip) with CHF of 220 W/cm² at wall superheat of 14°C, giving ~76% improvement in CHF compared to plain copper chip. While, copper on copper electrodeposited chip, deposited with a different technique, performed better in both CHF and aging. CHF of 192 W/cm² at wall superheat of 18.8°C was achieved for copper electrodeposited chip, giving ~30% enhancement compared to literature and ~54% enhancement when compared to plain copper chip.

Moreover, surface characterization techniques including Scanning Electron Microscope (SEM) with Energy- Dispersive X-Ray Spectroscopy (EDS), Fourier Transform Infrared (FTIR), and X-Ray Diffraction (XRD) were employed to study the morphologies, elemental species, and to confirm the presence of graphene and graphene oxide on the test surfaces.

Library of Congress Subject Headings

Heat-transfer media--Fluid dynamics; Fluid-structure interaction; Heat--Transmission; Ebullition; Microfluidics

Publication Date

7-19-2017

Document Type

Thesis

Student Type

Graduate

Degree Name

Mechanical Engineering (MS)

Department, Program, or Center

Mechanical Engineering (KGCOE)

Advisor

Satish G. Kandlikar

Advisor/Committee Member

Anju Gupta

Advisor/Committee Member

Agamemnon L. Crassidis

Comments

Physical copy available from RIT's Wallace Library at TP159.H4 R47 2017

Campus

RIT – Main Campus

Plan Codes

MECE-MS

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