{"id":{"repo_id":"vt","oai_identifier":"oai:vtechworks.lib.vt.edu:10919/43159"},"canonical_url":"https://search.dev.ndltd.org/etd/vt/oai:vtechworks.lib.vt.edu:10919/43159","repository":{"repo_id":"vt","name":"Virginia Tech","base_url":"https://vtechworks.lib.vt.edu/oai/request"},"display":{"title":"Modelling and prediction of flashing flow in short tubes","abstract":"The objective of this project was to develop a physically realistic method for predicting the flowrates in short tubes. A physically realistic model, though based on tests with one refrigerant, could be extrapolated to other refrigerants and to other refrigeration systems. Most of the existing methods of predicting flowrates are achieved by doing a lot of experimental work and developing empirical or semi-empirical relations; because of the high degree of empiricism they are only valid for the refrigerant used in the experiment. Eliminating material constraints and high degrees of empiricism from the prediction model was considered as a matter of utmost importance. A critical flow model was developed based on a vapor generation model. The model is built on the observation that choked short tube flow consist of a liquid core and a vapor annulus. Only three empirical factors were used, two to account for the assumptions made in the model development and the other to account for the area reduction due to vena contracta. The critical flow model predicted CFC and HCFC flow data with a maximum error of 13%. It failed in predicting flow data on water.","abstract_html":"The objective of this project was to develop a physically realistic method for predicting the flowrates in short tubes. A physically realistic model, though based on tests with one refrigerant, could be extrapolated to other refrigerants and to other refrigeration systems. Most of the existing methods of predicting flowrates are achieved by doing a lot of experimental work and developing empirical or semi-empirical relations; because of the high degree of empiricism they are only valid for the refrigerant used in the experiment. Eliminating material constraints and high degrees of empiricism from the prediction model was considered as a matter of utmost importance. A critical flow model was developed based on a vapor generation model. The model is built on the observation that choked short tube flow consist of a liquid core and a vapor annulus. Only three empirical factors were used, two to account for the assumptions made in the model development and the other to account for the area reduction due to vena contracta. The critical flow model predicted CFC and HCFC flow data with a maximum error of 13%. It failed in predicting flow data on water.","abstract_has_math":false,"creators":["Padmaperuma, Dinnaga P."],"institution":"Virginia Tech","degree_name":"Master of Science","degree_level":"masters","degree_discipline":"Mechanical Engineering","degree_department":"Mechanical Engineering","school":null,"contributors":[],"advisors":[],"committee_chairs":[],"committee_members":[],"year":1992,"date_issued":"1992","date_published":"1992","updated_at":"2026-07-22T22:19:32Z","subjects":[],"languages":["en"],"rights":["In Copyright"],"rights_urls":["http://rightsstatements.org/vocab/InC/1.0/"],"identifier_entries":[{"key":"dc:identifier.other","label":"Dc Identifier Other","values":["etd-06112009-063446"],"render_values":[{"text":"etd-06112009-063446","href":null,"code":true}]}]},"links":{"outbound_url":"http://hdl.handle.net/10919/43159","outbound_label":"Handle","outbound_source":"dc:identifier.uri"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor.department","label":"Department","values":["Mechanical Engineering"]},{"key":"dc:creator","label":"Author","values":["Padmaperuma, Dinnaga P."]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date.accessioned","label":"Dc Date Accessioned","values":["2014-03-14T21:37:57Z"]},{"key":"dc:date.available","label":"Dc Date Available","values":["2014-03-14T21:37:57Z","2009-06-11"]},{"key":"dc:date.issued","label":"Date","values":["1992"]},{"key":"dc:publisher","label":"Institution","values":["Virginia Tech"]},{"key":"dc:type","label":"Dc Type","values":["Thesis"]},{"key":"dc:type.dcmitype","label":"Dc Type Dcmitype","values":["Text"]},{"key":"thesis:degree_discipline","label":"Discipline","values":["Mechanical Engineering"]},{"key":"thesis:degree_level","label":"Degree Level","values":["masters"]},{"key":"thesis:degree_name","label":"Degree Name","values":["Master of Science"]},{"key":"thesis:institution_name","label":"Thesis Institution Name","values":["Virginia Polytechnic Institute and State University"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language.iso","label":"Language (ISO)","values":["en"]},{"key":"dc:rights","label":"Dc Rights","values":["In Copyright"]},{"key":"dc:rights.uri","label":"Rights URI","values":["http://rightsstatements.org/vocab/InC/1.0/"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier.other","label":"Dc Identifier Other","values":["etd-06112009-063446"]},{"key":"dc:identifier.uri","label":"Identifier URI","values":["http://hdl.handle.net/10919/43159"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description.abstract","label":"Abstract","values":["The objective of this project was to develop a physically realistic method for predicting the flowrates in short tubes. 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It failed in predicting flow data on water."]},{"key":"dc:description.degree","label":"Dc Description Degree","values":["Master of Science"]},{"key":"dc:format.medium","label":"Dc Format Medium","values":["BTD"]},{"key":"dc:format.mimetype","label":"Dc Format Mimetype","values":["application/pdf"]},{"key":"dc:title","label":"Title","values":["Modelling and prediction of flashing flow in short tubes"]}]}],"canonical_facts":{"dc:contributor.department":["Mechanical Engineering"],"dc:creator":["Padmaperuma, Dinnaga P."],"dc:date.accessioned":["2014-03-14T21:37:57Z"],"dc:date.available":["2014-03-14T21:37:57Z","2009-06-11"],"dc:date.issued":["1992"],"dc:description.abstract":["The objective of this project was to develop a physically realistic method for predicting the flowrates in short tubes. A physically realistic model, though based on tests with one refrigerant, could be extrapolated to other refrigerants and to other refrigeration systems. 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