Simulation of condensation in a subcooled bubbly steam-water flow along a large vertical pipe

• Autorzy: Lucas D. , Prasser H.
• Języki publikacji: EN

Abstrakty

EN

Detailed experimental data obtained at the TOPFLOW facility for steam-water vertical pipe flow were used to test the complex interaction of local bubble distributions, bubble size distributions and local heat and mass transfer. Steam is injected into subcooled water and condenses during the upward flow. The model considers a large number of bubble classes (50). This allows the investigation of the influence of the bubble size distribution. The results of the simulations show a good agreement with experimental data. The condensation process is clearly slower, if large bubbles are injected (4 mm holes). Also the bubble break-up has a strong influence on the condensation process because of the change of the interfacial area. Some unsureness arises from the unknown interfacial area for large bubbles and possible uncertainties of the heat transfer coefficient.

Słowa kluczowe

EN

bubble size distribution; bubbly flow; phase transfer; vertical pipe

PL

przeniesienie fazowe; przepływ pęcherzykowy; rura pionowa

• Wydawca: Wydawnictwo Instytutu Maszyn Przepływowych PAN ; Komitet Termodynamiki i Spalania PAN
• Czasopismo: Archives of Thermodynamics
• Rocznik: 2005
• Tom: Vol. 26, no. 4
• Strony: 49--59
• Opis fizyczny: Bibliogr. 14 poz., tab., rys.

Twórcy

autor

Lucas D.

• Forschungszentrum Rossendorf e. V., Institute of Safety Research,. p.o. Box 510 119, D-01314 Dresden, Germany

autor

Prasser H.

• Forschungszentrum Rossendorf e. V., Institute of Safety Research,. p.o. Box 510 119, D-01314 Dresden, Germany

Bibliografia

• [1] LUCAS D., SHI J.-M., KREPPER E. AND PRASSER H.-M.: Models for the forces acting on bubbles in comparison with experimental data for vertical pipe flow, 3rd Int. Symposium on Two-Phase Flow Modelling and Experimentation, Pisa, Italy, 2004, Paper ha04.
• [2] LUCAS D. AND PRASSER H.-M.: Scaling effects in vertical bubbly pipe flow, 5th Int. Conf. on Multiphase Flow, ICMF'04, Yokohama, Japan, 2004, Paper No. 187.
• [3] LUCAS D., KREPPER E. AND PRASSER H.-M.: Development of bubble size distributions in vertical pipe flow by consideration of radial gas fraction profiles, 4th Int. Conf. on Multiphase Flow, ICMF'01, New Orleans, USA, 2001, Paper 378.
• [4] LUCAS D., KREPPER E. AND PRASSER H.-M.: Modelling of the evolution of bubble flow along a large vertical pipe, The 11th Int. Topical Meeting on Nuclear Reactor Thermal-Hydraulics (NURETH-11), Avignon, France, October 2-6, 2005, Paper 051.
• [5] TOMIYAMA A.: Struggle with computational bubble dynamics, 3rd Int. Conf. on Multiphase Flow, ICMF'98, Lyon, France, 1998.
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• [7] KREPPER E., LUCAS D, PRASSER H.-M.: On the modelling of bubbly flow in vertical pipes, Nuclear Eng. and Design 235(2005), 597-611.
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