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出版Radiation Biology and Health Physics Branch, Chalk River Laboratories, 1994
ISBN06601560329780660156033
URLhttp://books.google.com.hk/books?id=MdzaAAAAMAAJ&hl=&source=gbs_api
註釋The dcc-1 and dcc-2 experiments have provided the first data on dryout and quench behavior of internally heated uo2 debris in water. the pressure range of this data extends from 1 to 170 atmoshperes. both of the experiments used the annual core research reactor (acrr) at sandia national laboratories to simulate the effects of radioactive decay heating. the debris in dcc-1 ranged from 75 microns to in excess of 10 mm in diameter, with a mean diameter of 0.75 mm. the bed depth was 0.5 m and the porosity was 0.345. dryout heat fluxes ranged from about 41 kw/m sup(2) (0.021 w/g) at a saturation temperature of 100 degrees celcius to about 69 kw/m sup(2) (0.021 w/g) at 340 degrees celcius. this measured pressure dependence is a factor of two to three lower than predicted by the analytical models. this is believed to be due to the breadth of the debris distribution, but the evidence is inconclusive. quenches of dried debris took hours to complete. quench fronts progressed uniformly without the liquid fingers observed in large particle tests. the debris distribution in dcc-2 was much narrower than in dcc 1, with the majority of particles having diameters between 0.5 and 8 mm. a small amount of "fines" with diameters down to 75 microns was added to the mixture. in dcc-2, thermally stable local dry zones were observed at bed power below the conventional dryout point. these are believed to be caused by the concentration of fines creating a low permeability zone. data on global dryout, in which the bed bottom can dry out, agree well with analytical predictions. quenches of dry zones took about 10 minutes to complete. the quench fronts were not uniform, having a liquid finger which penetrated to the bottom of the bed before the quench was complete.