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Microgravity Two-Phase Flow TransitionTwo-phase flows under microgravity condition find a large number of important applications in fluid handling and storage, and spacecraft thermal management. Specifically, under microgravity condition heat transfer between heat exchanger surfaces and fluids depend critically on the distribution and interaction between different fluid phases which are often qualitatively different from the gravity-based systems. Heat transfer and flow analysis in two-phase flows under these conditions require a clear understanding of the flow pattern transition and development of appropriate dimensionless scales for its modeling and prediction. The physics of this flow is however very complex and remains poorly understood. This has led to various inadequacies in flow and heat transfer modeling and has made prediction of flow transition difficult in engineering design of efficient thermal and flow systems. In the present study the available published data for flow transition under microgravity condition are considered for mapping. The transition from slug to annular flow and from bubbly to slug flow are mapped using dimensionless variable combination developed in a previous study by the authors. The result indicate that the new maps describe the flow transitions reasonably well over the range of the data available. The transition maps are examined and the results are discussed in relation to the presumed balance of forces and flow dynamics. It is suggested that further evaluation of the proposed flow and transition mapping will require a wider range of microgravity data expected to be made available in future studies.
Document ID
20000007142
Document Type
Conference Paper
Authors
Parang, M.
(Tennessee Univ. Knoxville, TN United States)
Chao, D.
(NASA Lewis Research Center Cleveland, OH United States)
Date Acquired
August 19, 2013
Publication Date
January 1, 1999
Subject Category
Fluid Mechanics And Thermodynamics
Report/Patent Number
AIAA Paper 99-0843
Meeting Information
37th Aerospace Sciences(Reno, NV)
Funding Number(s)
PROJECT: RTOP 963-25-0F
Distribution Limits
Public
Copyright
Work of the US Gov. Public Use Permitted.
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