Abstract

An experimental and analytical study of bubble nucleation characteristics for a polished aluminum surface under sub-cooled flow boiling of water is conducted. A high magnification (up to 1350X) microscope and an atomic force magnifier were used to visualize the aluminum surface to determine a range of cavity sizes on the heater surface as well as gain insight into the shape of the cavity. A high-speed camera was incorporated to study the actual bubble nucleation from these cavities. A review of existing theoretical models available in literature to predict bubble nucleation characteristics in flow boiling is also presented. A new bubble nucleation model is proposed which uses experimentally determined bubble geometry and results from computational fluid dynamics (CFD) modeling. Experimental data was collected through the use of the high-speed flow visualization system available in RIT's Thermal Fluid Laboratory. The data is obtained to study the effects of sub-cooling, flow rate, and wall superheat on the nucleation characteristics of different size cavities. This data is also compared with existing models as well as the one proposed in this investigation.

Library of Congress Subject Headings

Nucleate boiling--Mathematical models; Ebullition--Mathematical models; Heat--Transmission--Measurement; Fluid dynamic measurements

Publication Date

1995

Document Type

Thesis

Department, Program, or Center

Mechanical Engineering (KGCOE)

Advisor

Pavi, Glaudia

Advisor/Committee Member

Hefner, R.

Advisor/Committee Member

Nye, Alan

Comments

Note: imported from RIT’s Digital Media Library running on DSpace to RIT Scholar Works. Physical copy available through RIT's The Wallace Library at: QC304.C278 1995

Campus

RIT – Main Campus

Share

COinS