{"id":{"repo_id":"wustl","oai_identifier":"oai:openscholarship.wustl.edu:eng_etds-1557"},"canonical_url":"https://search.dev.ndltd.org/etd/wustl/oai:openscholarship.wustl.edu:eng_etds-1557","repository":{"repo_id":"wustl","name":"Washington University in St. Louis","base_url":"https://openscholarship.wustl.edu/do/oai/"},"display":{"title":"Nucleation Dynamics for Water Condensation on Hydrophobic Surfaces in the Presence of Non-Condensable Gases","abstract":"The density and rate of nucleation (here-in called nucleation density rate) significantly influences the heat transfer performance during dropwise condensation, as more than 70% of the total heat transfer happen for droplets smaller than 10 μm. Based on the classical nucleation theory, supersaturation strongly influences nucleation dynamics. However, the presence of non-condensable gas can strongly reduce the nucleation density rate by forming a vapor-depleted gas diffusion layer. Therefore, this work studied the relationship between nucleation density rate and supersaturation ratio during dropwise condensation on subcooled smooth hydrophobic surfaces with the presence of non-condensable gases in a custom-built condensation chamber. High-speed imaging and high-resolution microscopy enabled the experimental quantification of condensation dynamics. These were then compared to theoretical values based on the classical nucleation density. Based on the present experiments and a size distribution model, the relationship between heat transfer rate and supersaturation ratio were analyzed. Finally, through experimental observations, it is shown that the fast movement of relatively larger droplets can disturb the diffusion layer and enhance the nucleation density rate.","abstract_html":"The density and rate of nucleation (here-in called nucleation density rate) significantly influences the heat transfer performance during dropwise condensation, as more than 70% of the total heat transfer happen for droplets smaller than 10 μm. Based on the classical nucleation theory, supersaturation strongly influences nucleation dynamics. However, the presence of non-condensable gas can strongly reduce the nucleation density rate by forming a vapor-depleted gas diffusion layer. Therefore, this work studied the relationship between nucleation density rate and supersaturation ratio during dropwise condensation on subcooled smooth hydrophobic surfaces with the presence of non-condensable gases in a custom-built condensation chamber. High-speed imaging and high-resolution microscopy enabled the experimental quantification of condensation dynamics. These were then compared to theoretical values based on the classical nucleation density. Based on the present experiments and a size distribution model, the relationship between heat transfer rate and supersaturation ratio were analyzed. Finally, through experimental observations, it is shown that the fast movement of relatively larger droplets can disturb the diffusion layer and enhance the nucleation density rate.","abstract_has_math":false,"creators":["Jiang, Xinyu"],"institution":null,"degree_name":"Master of Science (MS)","degree_level":"Thesis","degree_discipline":"Mechanical Engineering & Materials Science","degree_department":null,"school":null,"contributors":["Patricia Weisensee","David Peters, Ramesh Agarwal"],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2020,"date_issued":"2020-05-15T07:00:00Z","date_published":"2020-05-15T07:00:00Z","updated_at":"2026-07-24T06:13:14Z","subjects":["dropwise condensation","nucleation density rate","heat transfer rate","Engineering"],"languages":["English (en)"],"rights":["I have not registered my thesis with the U.S. Copyright Office, but intend to later."],"rights_urls":[],"identifier_entries":[{"key":"dc:identifier","label":"Identifier","values":["https://openscholarship.wustl.edu/eng_etds/691"],"render_values":[{"text":"https://openscholarship.wustl.edu/eng_etds/691","href":"https://openscholarship.wustl.edu/eng_etds/691","code":true}]}]},"links":{"outbound_url":"https://doi.org/10.7936/d20r-ey56","outbound_label":"DOI","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor","label":"Contributor","values":["Patricia Weisensee","David Peters, Ramesh Agarwal"]},{"key":"dc:creator","label":"Author","values":["Jiang, Xinyu"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date.available","label":"Dc Date Available","values":["2022-04-17T07:00:00Z"]},{"key":"thesis:degree_discipline","label":"Discipline","values":["Mechanical Engineering & Materials Science","McKelvey School of Engineering"]},{"key":"thesis:degree_level","label":"Degree Level","values":["Thesis"]},{"key":"thesis:degree_name","label":"Degree Name","values":["Master of Science (MS)"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["dropwise condensation","nucleation density rate","heat transfer rate","Engineering"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language","label":"Dc Language","values":["English (en)"]},{"key":"dc:rights","label":"Dc Rights","values":["I have not registered my thesis with the U.S. Copyright Office, but intend to later."]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["https://doi.org/10.7936/d20r-ey56","https://openscholarship.wustl.edu/eng_etds/691"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description.abstract","label":"Abstract","values":["The density and rate of nucleation (here-in called nucleation density rate) significantly influences the heat transfer performance during dropwise condensation, as more than 70% of the total heat transfer happen for droplets smaller than 10 μm. Based on the classical nucleation theory, supersaturation strongly influences nucleation dynamics. However, the presence of non-condensable gas can strongly reduce the nucleation density rate by forming a vapor-depleted gas diffusion layer. Therefore, this work studied the relationship between nucleation density rate and supersaturation ratio during dropwise condensation on subcooled smooth hydrophobic surfaces with the presence of non-condensable gases in a custom-built condensation chamber. High-speed imaging and high-resolution microscopy enabled the experimental quantification of condensation dynamics. These were then compared to theoretical values based on the classical nucleation density. Based on the present experiments and a size distribution model, the relationship between heat transfer rate and supersaturation ratio were analyzed. Finally, through experimental observations, it is shown that the fast movement of relatively larger droplets can disturb the diffusion layer and enhance the nucleation density rate."]},{"key":"dc:title","label":"Title","values":["Nucleation Dynamics for Water Condensation on Hydrophobic Surfaces in the Presence of Non-Condensable Gases"]}]}],"canonical_facts":{"dc:contributor":["Patricia Weisensee","David Peters, Ramesh Agarwal"],"dc:creator":["Jiang, Xinyu"],"dc:date.available":["2022-04-17T07:00:00Z"],"dc:description.abstract":["The density and rate of nucleation (here-in called nucleation density rate) significantly influences the heat transfer performance during dropwise condensation, as more than 70% of the total heat transfer happen for droplets smaller than 10 μm. Based on the classical nucleation theory, supersaturation strongly influences nucleation dynamics. However, the presence of non-condensable gas can strongly reduce the nucleation density rate by forming a vapor-depleted gas diffusion layer. Therefore, this work studied the relationship between nucleation density rate and supersaturation ratio during dropwise condensation on subcooled smooth hydrophobic surfaces with the presence of non-condensable gases in a custom-built condensation chamber. High-speed imaging and high-resolution microscopy enabled the experimental quantification of condensation dynamics. These were then compared to theoretical values based on the classical nucleation density. Based on the present experiments and a size distribution model, the relationship between heat transfer rate and supersaturation ratio were analyzed. Finally, through experimental observations, it is shown that the fast movement of relatively larger droplets can disturb the diffusion layer and enhance the nucleation density rate."],"dc:identifier":["https://doi.org/10.7936/d20r-ey56","https://openscholarship.wustl.edu/eng_etds/691"],"dc:language":["English (en)"],"dc:rights":["I have not registered my thesis with the U.S. Copyright Office, but intend to later."],"dc:subject":["dropwise condensation","nucleation density rate","heat transfer rate","Engineering"],"dc:title":["Nucleation Dynamics for Water Condensation on Hydrophobic Surfaces in the Presence of Non-Condensable Gases"],"thesis:degree_discipline":["Mechanical Engineering & Materials Science","McKelvey School of Engineering"],"thesis:degree_level":["Thesis"],"thesis:degree_name":["Master of Science (MS)"]},"updated_at":"2026-07-24T06:13:14Z"}