Nonequilibrium vapor-generation model for flashing flows

Conference · Thu Jan 01 04:00:00 EST 1981

OSTI ID:5341944

Saha, P.; Abuaf, N.; Wu, B. J.C.

A nonequilibrium vapor generation model for flashing flows is presented. The model consists of a flashing inception point, a bubbly flow regime followed by a bubbly-slug regime, an annular or annular-mist regime, and finally a dispersed-droplet regime. Existence of superheated liquid at the inception point and beyond is recognized. The vapor generation rate in each flow regime is calculated from the estimates for interfacial area density and net interfacial heat flux. However, the bubble number density at the flashing inception point was varied to obtain optimum fits with the void fraction data taken in a vertical converging-diverging nozzle. The interfacial area density at the inception point, thus determined, showed a rapid increase with the decrease in the liquid superheat at that point. This trend is correct since in the limit of thermal equilibrium flow where the liquid superheat approaches zero, the interfacial area for heat and mass transfer should approach infinity. 32 refs., 7 figs., 1 tab.

• Research Organization: Brookhaven National Lab., Upton, NY (USA)
• Sponsoring Organization: USDOE; Nuclear Regulatory Commission
• DOE Contract Number: AC02-76CH00016
• OSTI ID: 5341944
• Report Number(s): BNL-NUREG--29510; CONF-810804--7; ON: TI85018228
• Country of Publication: United States
• Language: English

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