Link to the University of Pittsburgh Homepage
Link to the University Library System Homepage Link to the Contact Us Form

Ultra-Fast Transient Pool Boiling under High Pressure and Subcoolings

Villarreal, Ezekiel (2023) Ultra-Fast Transient Pool Boiling under High Pressure and Subcoolings. Doctoral Dissertation, University of Pittsburgh. (Unpublished)

Download (10MB) | Preview


Growing global energy consumption and demand has led to growing interest in a variety of energy options and new technologies for various applications. A fundamental understanding of the foundational physics is essential in being able to design and safely operate future energy options and technologies. Of particular interest presently are energy sources that produce little to no carbon emissions. Nuclear energy is a vital component of the repertoire of zero-carbon energy sources. Under accident conditions nuclear reactors can undergo high-energy, fast power transients. In addition, advancing technologies are required to dissipate larger quantities of heat at shorter timescales. The goal of this work is to investigate ultra-fast transient pool boiling regimes to enhance the fundamental understanding of this phenomenology and to establish a basis for future energy and technological application.
In this work, temperature, heat transfer, and high-speed imagery of transient boiling events are collected during ultra-fast (up to 250,000°C/s) heating pulses to define the behavior and mechanisms occurring. While pool boiling responses have been studied previously at longer time scales, this work provides fundamental understanding of the mechanisms in the ultra-fast timescale. To accomplish this a high-pressure, variable temperature, transient boiling system is created to experimentally study a variety of factors related to ultra-fast transient boiling. These factors include combinations of pressures and water subcoolings, the heater surface condition, the heating shape, and the heating level. The water is heated by, and measurement are taken from, a thin wire inside a pressure vessel. Parameter comparison studies are performed to provide a relative importance of the tested parameters on a variety of experimental outcomes. Additional investigations of the material failure mechanisms under extreme heating rates are presented.
Ultimately, this work presents the transient boiling heat transfer and associated phenomena of numerous experimental conditions under ultra-fast heating. This will provide a fundamental evaluation of an area of pool boiling that has not been previously explored. The results can provide a basis to drive growth and future study both in the nuclear industry and in the heat transfer industry, where there is an ever-increasing demand for higher heat transfer and controllable configurations.


Social Networking:
Share |


Item Type: University of Pittsburgh ETD
Status: Unpublished
CreatorsEmailPitt UsernameORCID
Villarreal, Ezekieletv1@pitt.eduETV10000-0002-9467-5142
ETD Committee:
TitleMemberEmail AddressPitt UsernameORCID
Thesis AdvisorBan, HengHeng.ban@pitt.eduhengban
Committee MemberHornbostel, Katherinehornbostel@pitt.edukmo68
Committee MemberCongedo, Thomastvc9@pitt.edutvc9
Committee MemberChen,
Date: 13 June 2023
Date Type: Publication
Defense Date: 29 March 2023
Approval Date: 13 June 2023
Submission Date: 23 March 2023
Access Restriction: No restriction; Release the ETD for access worldwide immediately.
Number of Pages: 248
Institution: University of Pittsburgh
Schools and Programs: Swanson School of Engineering > Mechanical Engineering
Degree: PhD - Doctor of Philosophy
Thesis Type: Doctoral Dissertation
Refereed: Yes
Uncontrolled Keywords: Nuclear Accident, Reactivity Initiated Accident, Experimental, Boiling Regimes, High Energy Heat Transfer, Fast Heating, Ultrafast Heating
Date Deposited: 13 Jun 2023 14:10
Last Modified: 13 Jun 2023 14:10


Monthly Views for the past 3 years

Plum Analytics

Actions (login required)

View Item View Item