Flow regime transition criteria consistent with two-fluid model for vertical two-phase flow. [PWR]

Technical Report · Fri Apr 01 04:00:00 EST 1983

OSTI ID:6243670

Mishima, K; Ishii, M

Traditional flow-regime criteria based on the gas and liquid superficial velocities may not be suitable to the analyses of rapid transient or entrance flows by the two-fluid model. Under these conditions, direct geometrical parameters such as the void fraction should be used in flow-regime criteria. From this point of view, new flow-regime criteria for upward gas-liquid flow in vertical tubes have been developed. These new criteria can be compared to existing criteria and experimental data under steady-state and fully developed flow conditions by using relative velocity correlations. The criteria showed reasonable agreements with the existing data for atmospheric air-water flows. Further comparisons with data for steam-water in round tubes and a rectangular channel at relatively high system pressures have been made. The results confirmed that the present flow regime transition criteria could be applied over wide ranges of parameters as well as to boiling flow.

• Research Organization: Argonne National Lab., IL (USA)
• DOE Contract Number: W-31109-ENG-38
• OSTI ID: 6243670
• Report Number(s): NUREG/CR-3338; ANL-83-42; ON: DE83013247
• Country of Publication: United States
• Language: English

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