Toward a local drift flux model for high-pressure, subcooled, convective boiling flows
نویسندگان
چکیده
Forced convective boiling is of great interest for several applications in the power and process industry, particularly nuclear plants. Under certain nominal, incidental or accidental conditions, a crisis may occur resulting meltdown heating surface. It then essential to predict as accurately possible thermal-hydraulic conditions leading occurrence this crisis. Such an objective cannot reasonably be achieved without good description associated two-phase flow. The present study twofold: (1) identify necessary key parameters correctly describing flows, (2) didactic way original stationary local model involving these parameters. This new primarily based on four mixture balance equations, submodel vapor generation rate, turbulence inspired by pioneering work [25]. results obtained with flow are compared extensive experimental data set R12/R134a facility. comparison clearly demonstrates that contains fewer submodels describe structure under pressurized water reactor conditions. Subcooled acceptably described model. However, higher values void fraction, always predicts nonexistent fraction peak near wall overpredicts liquid temperatures. behavior explained by: (i) inadequacy radial modeling, (ii) use Prandtl's analogy whose validity questionable, (iii) too simplistic rate.
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ژورنال
عنوان ژورنال: International Journal of Heat and Mass Transfer
سال: 2021
ISSN: ['1879-2189', '0017-9310']
DOI: https://doi.org/10.1016/j.ijheatmasstransfer.2021.121506