Adiabatic two phase flow regime data and modeling for zero and reduced (horizontal flow) acceleration fields /
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| Other Authors: | , , |
| Format: | Thesis Book |
| Language: | English |
| Published: |
1993.
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| Subjects: | |
| Online Access: | ProQuest, Abstract Link to OAKTrust copy |
| Abstract: | Two phase, adiabatic, cocurrent, one or two component flows in circular cross section tubes are studied in one and reduced-G (horizontal) and zero-G environments. Two major contributions are reported in this work. The first is the collection, validation, and tabulation of an extensive database of dichlorodifluoromethane (R12) two phase flow regime data. These data include zero and Earth acceleration flow points and the only available lunar and Martian acceleration data. The data were obtained via the parabolic flight path of the National Aeronautics and Space Administration (NASA) KC-135 aircraft. A rigorous method of data validation is developed that analyzes tri-axial, orthogonal accelerometer values, flow rate, temperature, and pressure data, ensuring steady-state conditions and the desired acceleration field for a given flow point. The vapor R12 flow rates ranged from 0.0010 to 0.0110 kg/s and liquid mass flow rates ranged from 0.0001 kg/s to 0.0600 kg/s. Inside diameter sections of 0.0105 m and 0.0047 m were used during testing. Flow regimes were recorded at 1000 frames per second after a development length of 179 L/D's for the larger tube and 401 L/D's for the smaller tube. 130 zero-G, 39 lunar-G points, 39 Martian-G points, and 118 one-G points were validated, including bubbly, slug or plug, annular, and stratified flows. The second major contribution is the development of new flow regime transition models that contain acceleration as an explicit variable and are applicable to a wide range of flow conditions. Annular to slug, annular to dispersed, bubbly to slug, stratified to annular, and stratified to slug transition models are presented. These new models contain empirical information only in the use of the friction factors. These new models were compared with other models for zero and reduced-G against the data presented here and against zero and accompanying (when available) Earth acceleration data obtained by other researchers, and the new models are shown to outperform the current state of the art in zero and reduced-G modeling. |
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| Item Description: | Vita. "Major subject: Nuclear Engineering." |
| Physical Description: | xxiii, 322 leaves : illustrations ; 28 cm |
| Bibliography: | Includes bibliographical references. |