BOILING-WATER VOID DISTRIBUTION AND SLIP RATIO IN HEATED CHANNELS. Final Report

Distribution of void and the behavior of slip ratio in light water in a rectangular heated test section were investigated with a beta-particle- attenuation technique. The amount of void in the subcooled region was determined to within plus or minus 3% void. Various combinations of the following conditions were investigated: pressures from 700 to 1300 psia, mass flow rates from 1.0 to 3.0 x 10/sup 6/ lb/hr/ft/sup 2/, and heat fluxes from 0.10 to 0.60 x 10/sup 6/ Btu/hr/ft/sup 2/. The test section was heated with both a-c and d-c power, and no significant difference in the results was detected. It was found that the slip ratio at a high Reynolds number is much more a function of the Reynolds number than of pressure. Furthermore, for Reynolds numbers between 50,000 and 90,000 the slip ratio at constant void fraction reaches a maximum. Some of the recent theoretical correlations of subcooled and bulk boiling were tested. The experimental bulk-boiling results compare reasonably well with the most recent theoretical models. Void fraction at zero quality can be correlated by the expression: alpha = 0-113 X/sub e//sub x/ (L/LB)/(P/sub c//P/sub s//sub a//sub t/ - 1). (auth)