A Study on the Violent Interactions of an Immiscible Drop impacting on a Superheated Pool

Handle URI:
http://hdl.handle.net/10754/317236
Title:
A Study on the Violent Interactions of an Immiscible Drop impacting on a Superheated Pool
Authors:
Alchalabi, Mohamad
Abstract:
ABSTRACT A Study on the Violent Interactions of an Immiscible Drop Impacting on a Superheated Pool Mohamad Alchalabi The interactions between two immiscible liquids of different temperatures can be violent to the extent of causing harm to individuals, or damage to equipment, especially when used in the industry. Only a few studies investigated these interactions but they could not produce the violent interactions often reported by the industry, and therefore their results did not help much to develop clear understanding of the dynamics of these interactions. In this work, a high speed imaging system operated at 100,000 frames per second was utilized to record the events and phenomena taking place upon the impact of Perfluorohexane droplet at room temperature onto a hot soybean oil pool at temperatures as high as 300 ºC. The impact velocity was varied by varying the height of the droplet before it pinches off under its own weight. The recorded events identified the occurrence of vortex ring vapor explosions, weak and strong nucleate boiling, and film boiling. An impact velocity vs. oil temperature diagram identifying the regions in which each of these phenomena takes place was generated, and the dynamics driving their occurrences were explored. The vortex ring vapor explosions were found to become less violent as the impact velocity was increased, which was attributed to the existence of a smaller amount of liquid Perfluorohexane within the rings at high speed impacts, which does evaporate but does not expand violently. Weak nucleate boiling occurred at very high impact velocities relatively. As the temperature is increased, however, they start 5 turning into strong nucleate boiling. The strong nucleate boiling usually starts right upon impact, and when the temperature of the oil at one impact velocity is increased, it starts turning into film boiling, in which the liquid Perfluorohexane is covered by a vapor layer of its own vapor.
Advisors:
Thoroddsen, Sigurdur T ( 0000-0001-6997-4311 )
Committee Member:
Claudel, Christian G. ( 0000-0003-0702-6548 ) ; Li, Erqiang ( 0000-0002-5003-0756 )
KAUST Department:
Physical Sciences and Engineering (PSE) Division
Program:
Mechanical Engineering
Issue Date:
May-2014
Type:
Thesis
Appears in Collections:
Theses; Physical Sciences and Engineering (PSE) Division; Mechanical Engineering Program

Full metadata record

DC FieldValue Language
dc.contributor.advisorThoroddsen, Sigurdur Ten
dc.contributor.authorAlchalabi, Mohamaden
dc.date.accessioned2014-05-21T09:21:13Zen
dc.date.available2014-05-21T09:21:13Zen
dc.date.issued2014-05en
dc.identifier.urihttp://hdl.handle.net/10754/317236en
dc.description.abstractABSTRACT A Study on the Violent Interactions of an Immiscible Drop Impacting on a Superheated Pool Mohamad Alchalabi The interactions between two immiscible liquids of different temperatures can be violent to the extent of causing harm to individuals, or damage to equipment, especially when used in the industry. Only a few studies investigated these interactions but they could not produce the violent interactions often reported by the industry, and therefore their results did not help much to develop clear understanding of the dynamics of these interactions. In this work, a high speed imaging system operated at 100,000 frames per second was utilized to record the events and phenomena taking place upon the impact of Perfluorohexane droplet at room temperature onto a hot soybean oil pool at temperatures as high as 300 ºC. The impact velocity was varied by varying the height of the droplet before it pinches off under its own weight. The recorded events identified the occurrence of vortex ring vapor explosions, weak and strong nucleate boiling, and film boiling. An impact velocity vs. oil temperature diagram identifying the regions in which each of these phenomena takes place was generated, and the dynamics driving their occurrences were explored. The vortex ring vapor explosions were found to become less violent as the impact velocity was increased, which was attributed to the existence of a smaller amount of liquid Perfluorohexane within the rings at high speed impacts, which does evaporate but does not expand violently. Weak nucleate boiling occurred at very high impact velocities relatively. As the temperature is increased, however, they start 5 turning into strong nucleate boiling. The strong nucleate boiling usually starts right upon impact, and when the temperature of the oil at one impact velocity is increased, it starts turning into film boiling, in which the liquid Perfluorohexane is covered by a vapor layer of its own vapor.en
dc.language.isoenen
dc.subjectInteractionsen
dc.subjectImpacten
dc.subjectExplosionen
dc.subjectVortexen
dc.subjectRingen
dc.subjectDynamicsen
dc.titleA Study on the Violent Interactions of an Immiscible Drop impacting on a Superheated Poolen
dc.typeThesisen
dc.contributor.departmentPhysical Sciences and Engineering (PSE) Divisionen
thesis.degree.grantorKing Abdullah University of Science and Technologyen_GB
dc.contributor.committeememberClaudel, Christian G.en
dc.contributor.committeememberLi, Erqiangen
thesis.degree.disciplineMechanical Engineeringen
thesis.degree.nameMaster of Scienceen
dc.person.id124227en
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