MEASUREMENTS OF BURNOUT CONDITIONS FOR FLOW OF BOILING WATER IN VERTICAL ANNULI. PART I

Technical Report · Mon Jan 01 04:00:00 EST 1962

OSTI ID:4721291

Becker, K M; Hernborg, G

Measurements were made of burnout conditions for flow of boiling water in an annulus with an inner diameter of 9.92 mm, an outer diameter of 17.42 mm, and a heated length of 608 mm. Data were obtained for external heating only, internal heating only, and dual uniform and nonuniform henting. The following ranges of variables were studied and 978 burnout measurements were obtained: pressure, 8.5 to 37.5 kg/cm/sup 2/; inlet subcooling, 60 to 205 deg C; steam quality, 0.10 to 0.91; inner surface heat flux 0 to 303 W/cm/sup 2/; outer surface hent flux 0 to 374 W/cm/sup 2/ and mass velocity, 71 to 961 kg/m/sup 2/ sec. The results are presented in diagrams where the burnout steam qualities, x/ sub BO/, were plotted against the pressure with the surface heat fluxes as parameters. The data were correlated by curves. The scatter of the data around the curves is less than plus or minus 5 per cent. In the case of equal heat fluxes on both walls of the annulus, burnout always occurred on the inner wall, and the data compared rather well with round duct data. When the annulus was heated internally oriy, the data showed very low burnout values in comparison with the results for dual heating and round ducts. This disagreement was explained by considering the climbing film flow model and by the fact thnt only a fraction of the channel perimeter was heated. For external heating, the dnta are somewhat lower than corresponding round duct data, but rather high in comparison with irternal heating. The climbing film flow model was also used to interpret this observation. For dual non-unlform heating, it was found that the outer surface may be overloaded from 30 to 70 per cent compared with the inner surface without reducing the margin of safety in respect of burnout for the annulus. It was further observed that when the heat flux for the wall on which burnout occurs is increased, the burnout steam quality for the channel decreases. If, however, the heat flux for the opposite wall is increased, the burnout steam quality also increases. It was also observed that the highest burnout values are obtained when burnout occurs simultaneously on both cylinders. Finally the results were compared with annuli and rod cluster data in published works, and a method for predicting burnout conditions in rod clusters is proposed. (auth)

• Research Organization: Aktiebolaget Atomenergi, Stockholm
• NSA Number: NSA-17-010789
• OSTI ID: 4721291
• Report Number(s): AE-100
• Country of Publication: Country unknown/Code not available
• Language: English

Related Subjects

BOILING
BURNOUT
CONFIGURATION
COOLING
DIAGRAMS
ENGINEERING AND EQUIPMENT
ERRORS
FILMS
FLOW MODELS
FLUID FLOW
FUEL ELEMENTS
HEATING
MASS
MATHEMATICS
MEASURED VALUES
MOCKUP
PERFORMANCE
PRESSURE
RODS
STANDARDS
STEAM
STEAM QUALITY
SUBCOOLING
SUPERHEATING
SURFACES
TUBES
VELOCITY
WATER