A research program is proposed for the development of a validated methodology for predicting the ex-vessel buoyancy-driven flows in the hot leg and steam generator of a Westinghouse plant, and in the candy cane hot leg of a B&W plant. The proposed Phase I work plan consists of (a) reviewing available Westinghouse experimental data and simulating the experimental configuration, (b) validating the model using the test data and updating the odel, if required, (c) performing sensitivity calculations assessing the effects of flow and geometric parameters on the established flow, and (d) providing best estimates for buoyancy-driven flows within B&M hot legs.
Anticipated Results:The proposed program will provide NRC with a validated methodology and associated parametric /sensitivity calculations for buoyancy-driven flows in the hot generators of PSR plants. The effort will assist NRC in the design and interpretation of any future experimental work, and in the assessment of the effects of buoyancy-driven flows on severe accidents in PWRs.
