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Analytical study of critical heat flux in two-phase thermosyphon: relationship between maximum falling liquid rate and critical heat flux
ANNUAL LITERATURE SURVEY 1996 117 quantitative improvement over both planetary geostrophy and quasi-geostrophy for large-scale flows, and its evolution is in good agreement with a primitive equation model. (from Author)
Momentum rate probe for use with two-phase flows Bush S.G., Bennett J.B., Sojka P.E., Panchagnula M.V. & Plesniak M.W., Review of Scientific Instruments, 1996, 67/5 (1878-1885). In English. This paper concentrates on an instrument for measuring the momentum rate of two-phase flows. The design and construction details are provided. The device utilizes a conelike body to turn the flow from the axial to the radial direction. The force resulting from the change in momentum rate of the turning flow is measured using a straingage-instrumented cantilevered beam. The instrument is applicable to a wide range of flows. (after Authors) Phase splitting of wet steam in annular flow through a horizontal branching tee Sze-Foo Chien, SPE Production & Facilities, 1996, 11/2 (83-88). In English. A phase-splitting equation for flow of a two-phase fluid through a tee junction was derived. It shows that the fluid quality at an outlet of the tee is determined by the relationship between the liquid and vapor extraction ratios of the fluid through that outlet. This equation applies to any tee junction regardless of its geometry, orientation, and inclination. This paper presents its application to the flow of wet steam through a horizontal branching tee. Experimental data were for wet steam flowing through a standard branching tee, were analyzed focusing on the effect of the vapor-extraction ratio of the run stream on the liquid-extraction ratio of the same stream. A correlation between these two extraction ratios has been established with steam quality, superficial vapor velocity, and critical velocity at the inlet to the tee as controlling parameters. Using this correlation and the phase-split equation, it was possible to predict steam qualities existing from horizontal branching tees to within +/-15*/, of the experimental values, which is more accurate than other phase-splitting models. (from Author) Vertical multiphase flow correlations for high production rates and large tubnlars Aggour M.A., Al-Yousef H.Y. & A1-Muraikhi A.J., SPE Production & Facilities, 1996, I 1/1 (41-48). In English. This paper presents a comprehensive evaluation of existing correlations and modifications of some co rrelations to determine and recommend the best correlation or correlations for various field conditions. More than 400 field data sets covering tubing sizes from 2 3/8 to 7 in., oil rates up to 23 200 B/D, water cuts up to 95 %, and gas/ oil ratio (GOR) up to 927 scf/STB were used in this study. Considering all data combined, the Beggs and Brill correlation provided the best pressure predictions. However, the Hagedorn and Brown correlation was better for water cuts above 80%, while the Hasan and Kabir model was better for total liquid rates above 20 000 B/D. The Aziz correlation was significantly improved when the Orkiszewski flow-pattern transition criteria were used. (from Authors) A water-vapor permeable drying surface for thin films Bowser T.J. & Wilhelm L.R., Transactions - American Society of Agricultural Engineers, 1996, 39/2 (617-623). In English. A new drying technique for thin films of colloidal slurries and solutions has been proposed and evaluated. A bench-top representation of the proposed drying system was constructed to test feasibility and performance. Preliminary tests showed that a water-vapor permeable drying surface may be an attractive alternative to traditional thin-film drying methods. Four experiments, using modified eoru, potato, and rice starch films, were conducted. (from Authors) Analytical study of critical heat flux in two-phase thermosyphon: relationship between maximum falling liquid rate and critical heat flux Monde M., Transactions - ASME: Journal of Heat Transfer, 1996, 118/2 (422-428). In English. An analytical study has been done on the critical heat flux of a two-phase thermosyphon, in which a liquid film and a vapor film exist in a countercurrent annual flow. The CHF point on the thermosyphon is proved to correspond to a maximum falling liquid rate fed to the thermosyphon, which can be determined from three equations of momentum, its partial derivative with void fraction, and mass balance in the thermosyphon. This maximum point, furthermore, becomes identical to the point at which an envelope line generated from the momentum equation and its partial derivative intersects the mass balance line. The C H F calculated from the maximum liquid rate is found to be in fairly good agreement with the existing CHF data. (Author) Heat transfer of air/water two-phase flow in helicoidal pipes Xin R.C., Awwad A., Dong Z.F. & Ebadian M.A., Transactions - ASME: Journal of Heat Transfer, 1996, 118/2 (442-448). In English. Heat transfer of air/water two-phase flow in helicoidal pipes is experimentally investigated in this study. Three test sections were tested in axially horizontal, vertical, and inclined orientations. It has been found that the ratio of the average heat transfer coefficient to that of the water flow is affected by the water flow rate along with the Lockhart-Martinelli parameter. For a fixed water flow rate, there is a maximum heat transfer coefficient as the air flow rateincreases. The results indicate that tube diameter has a significant effect on the average heat transfer coefficient ratio. F o r large-tube-diameter coils, average heat transfer results vary from different orientations. For small-tube-diameter coils, orientation has an insignificant effect on the average heat transfer coefficient. Based on the experimental data, a set of correlations is proposed for the average heat transfer coefficient ratio versus the liquid superficial Reynolds number and Lockhart-Martinelli parameter. (Authors) Elastohydrodynamic lubrication by powder slurries Hua D.Y. & Khonsari M.M., Transactions- ASME. Journal of Tribology, 1996, 118/1 (67-73). In English.
Momentum rate probe for use with two-phase flows Bush S.G., Bennett J.B., Sojka P.E., Panchagnula M.V. & Plesniak M.W., Review of Scientific Instruments, 1996, 67/5 (1878-1885). In English. This paper concentrates on an instrument for measuring the momentum rate of two-phase flows. The design and construction details are provided. The device utilizes a conelike body to turn the flow from the axial to the radial direction. The force resulting from the change in momentum rate of the turning flow is measured using a straingage-instrumented cantilevered beam. The instrument is applicable to a wide range of flows. (after Authors) Phase splitting of wet steam in annular flow through a horizontal branching tee Sze-Foo Chien, SPE Production & Facilities, 1996, 11/2 (83-88). In English. A phase-splitting equation for flow of a two-phase fluid through a tee junction was derived. It shows that the fluid quality at an outlet of the tee is determined by the relationship between the liquid and vapor extraction ratios of the fluid through that outlet. This equation applies to any tee junction regardless of its geometry, orientation, and inclination. This paper presents its application to the flow of wet steam through a horizontal branching tee. Experimental data were for wet steam flowing through a standard branching tee, were analyzed focusing on the effect of the vapor-extraction ratio of the run stream on the liquid-extraction ratio of the same stream. A correlation between these two extraction ratios has been established with steam quality, superficial vapor velocity, and critical velocity at the inlet to the tee as controlling parameters. Using this correlation and the phase-split equation, it was possible to predict steam qualities existing from horizontal branching tees to within +/-15*/, of the experimental values, which is more accurate than other phase-splitting models. (from Author) Vertical multiphase flow correlations for high production rates and large tubnlars Aggour M.A., Al-Yousef H.Y. & A1-Muraikhi A.J., SPE Production & Facilities, 1996, I 1/1 (41-48). In English. This paper presents a comprehensive evaluation of existing correlations and modifications of some co rrelations to determine and recommend the best correlation or correlations for various field conditions. More than 400 field data sets covering tubing sizes from 2 3/8 to 7 in., oil rates up to 23 200 B/D, water cuts up to 95 %, and gas/ oil ratio (GOR) up to 927 scf/STB were used in this study. Considering all data combined, the Beggs and Brill correlation provided the best pressure predictions. However, the Hagedorn and Brown correlation was better for water cuts above 80%, while the Hasan and Kabir model was better for total liquid rates above 20 000 B/D. The Aziz correlation was significantly improved when the Orkiszewski flow-pattern transition criteria were used. (from Authors) A water-vapor permeable drying surface for thin films Bowser T.J. & Wilhelm L.R., Transactions - American Society of Agricultural Engineers, 1996, 39/2 (617-623). In English. A new drying technique for thin films of colloidal slurries and solutions has been proposed and evaluated. A bench-top representation of the proposed drying system was constructed to test feasibility and performance. Preliminary tests showed that a water-vapor permeable drying surface may be an attractive alternative to traditional thin-film drying methods. Four experiments, using modified eoru, potato, and rice starch films, were conducted. (from Authors) Analytical study of critical heat flux in two-phase thermosyphon: relationship between maximum falling liquid rate and critical heat flux Monde M., Transactions - ASME: Journal of Heat Transfer, 1996, 118/2 (422-428). In English. An analytical study has been done on the critical heat flux of a two-phase thermosyphon, in which a liquid film and a vapor film exist in a countercurrent annual flow. The CHF point on the thermosyphon is proved to correspond to a maximum falling liquid rate fed to the thermosyphon, which can be determined from three equations of momentum, its partial derivative with void fraction, and mass balance in the thermosyphon. This maximum point, furthermore, becomes identical to the point at which an envelope line generated from the momentum equation and its partial derivative intersects the mass balance line. The C H F calculated from the maximum liquid rate is found to be in fairly good agreement with the existing CHF data. (Author) Heat transfer of air/water two-phase flow in helicoidal pipes Xin R.C., Awwad A., Dong Z.F. & Ebadian M.A., Transactions - ASME: Journal of Heat Transfer, 1996, 118/2 (442-448). In English. Heat transfer of air/water two-phase flow in helicoidal pipes is experimentally investigated in this study. Three test sections were tested in axially horizontal, vertical, and inclined orientations. It has been found that the ratio of the average heat transfer coefficient to that of the water flow is affected by the water flow rate along with the Lockhart-Martinelli parameter. For a fixed water flow rate, there is a maximum heat transfer coefficient as the air flow rateincreases. The results indicate that tube diameter has a significant effect on the average heat transfer coefficient ratio. F o r large-tube-diameter coils, average heat transfer results vary from different orientations. For small-tube-diameter coils, orientation has an insignificant effect on the average heat transfer coefficient. Based on the experimental data, a set of correlations is proposed for the average heat transfer coefficient ratio versus the liquid superficial Reynolds number and Lockhart-Martinelli parameter. (Authors) Elastohydrodynamic lubrication by powder slurries Hua D.Y. & Khonsari M.M., Transactions- ASME. Journal of Tribology, 1996, 118/1 (67-73). In English.