scholarly journals ON THE BEHAVIOR OF AEROSOLS UNDER FAST REACTOR ACCIDENT CONDITIONS.

1969 ◽  
Author(s):  
A. W. Castleman, Jr. ◽  
F. L. Horn ◽  
G. C. Lindauer
Keyword(s):  
Fast Reactor ◽  
Reactor Accident ◽  
Accident Conditions

Pressure waves in sodium during a fast reactor accident

Meccanica ◽  
1975 ◽  
Vol 10 (2) ◽  
pp. 78-86
Author(s):  
Tullio Trombetti
Keyword(s):  
Fast Reactor ◽  
Pressure Waves ◽  
Reactor Accident

The reduction of I2 by H2O2 in aqueous solution

2001 ◽  
Vol 79 (3) ◽  
pp. 304-311 ◽  
Author(s):  
J M Ball ◽  
J B Hnatiw
Keyword(s):  
Aqueous Solution ◽  
Hydrogen Peroxide ◽  
Nuclear Reactor ◽  
Ph Dependence ◽  
Radiolysis Product ◽  
Molecular Iodine ◽  
Water Radiolysis ◽  
Reactor Accident ◽  
Rate Law ◽  
Accident Conditions

The reduction of I2 by hydrogen peroxide, a primary water radiolysis product, has been identified as a key reaction that would influence iodine volatility in nuclear reactor accident conditions (1–3). Although there have been a number of studies of the reduction of I2, there exists a great degree of controversy regarding the intermediates involved, the effect of buffers, and the general rate law (1–9). Because the rates and the mechanism of this reaction are important in predicting the pH dependence of iodine behaviour in reactor containment building after a postulated reactor accident, we have undertaken a kinetic study of I2 reduction by H2O2 in aqueous solution over a pH range of 6–9. The experiments were performed using stopped-flow instrumentation and monitoring the decay of I–3 spectrophotometrically. The effects of buffer catalysis have been examined by comparison of kinetic data obtained in sodium barbital (5,5-diethylbarbituric acid), disodium citrate, and disodium hydrogen phosphate buffers. The effect of buffers, combined with the complex acid dependence of the rate law, explains many of the discrepancies reported in earlier literature.Key words: hydrogen peroxide, molecular iodine, kinetics, iodine volatility.

Fission product releases from thoria and urania fuels under reactor accident conditions: Hot cell experiment #6 (HCE6)

2020 ◽  
Vol 144 ◽  
pp. 107510 ◽  
Author(s):  
Raymond S. Dickson ◽  
J. Stuart Bell ◽  
Robert F. O'Connor ◽  
Jeffrey Sheedy ◽  
Randy T. Peplinskie ◽  
...  
Keyword(s):  
Fission Product ◽  
Reactor Accident ◽  
Cell Experiment ◽  
Accident Conditions

Experimental Study on Sodium Column Fire of Sodium-Cooled Fast Reactor

2013 ◽  
Author(s):  
Kang-wei Peng ◽  
Zhi-gang Zhang ◽  
Ming Guo ◽  
Chao Wang ◽  
Shu-bin Sun
Keyword(s):  
High Temperature ◽  
Fast Reactor ◽  
Difficult Problem ◽  
Temperature Fields ◽  
Practical Significance ◽  
Liquid Sodium ◽  
Insulation Material ◽  
Reactor Accident ◽  
Temperature Liquid ◽  
Operation Pressure

In the operation of sodium-cooled fast reactor, accident caused by the leakage and combustion of liquid sodium is common, and it is a pivotal and difficult problem in research, construction and operation of sodium-cooled fast reactor internationally. In actual operation of sodium-cooled fast reactor, liquid sodium in sodium fire accident is difficult to form fog but mainly in columnar flow form due to low operation pressure and thermal insulation material wrapping the pipe, so experimental research about columnar fire is of much more practical significance. This paper focuses on combustion property on sodium column fire in the sodium-cooled fast reactor. Liquid sodium with high temperature will be poured into the combustion room via pouring high pressure nitrogen into sodium storage tank when solid sodium has been heated to enactment temperature; liquid sodium with high temperature will burn at combustion room with air forming sodium column fire. Initial temperature of sodium jet is about 200°C in experiment and spurt pressure is 0.2MPa, spurt flow is about 0.4–0.6m3 each hour. Temperature fields in combustion tank space and the catch plate in the bottom are measured through dozens of thermocouple distributed in combustion tank. No atomization phenomenon would exist in the pure sodium columnar fire in the space, the atomized fire triggered by splashed sodium from sodium stream striking the admittance plat and generate more than the high temperature of 900°C.

Analysis of Fuel-Coolant Interaction Potential in Sodium Cooled Fast Reactor Safety Experiments

2012 ◽  
Author(s):  
John C. Petrykowski
Keyword(s):  
Free Surface ◽  
Fast Reactor ◽  
National Laboratory ◽  
Oak Ridge ◽  
Model Free ◽  
Reactor Technology ◽  
Time Estimates ◽  
Property Data ◽  
Bubble Transport ◽  
Accident Conditions

Improved utilization of nuclear fuels, burning of actinides and advancements in safety have brought about renewed interest in sodium cooled fast reactor technology. In regards to this and in light of recent events which have focused attention on new concerns involving safety, analyses have recently been performed addressing beyond design basis accident conditions for which the existence of large quantities of vaporized fuel and coolant have been postulated. Specifically, for very low probability, but highly energetic core disruptive accidents in sodium cooled fast reactors, molten and vaporized fuel in contact with coolant can bring about a fuel coolant interaction leading to transformation of a significant inventory of coolant from liquid to vaporforme, with a potential for subsequent release of fuel as aerosol from the reactor vessel due to transport of fuel fragments and fuel aerosol by the vaporized fuel and coolant. Because general statements concerning the nature of these events were largely speculative, out-of-reactor experiments were conducted in the mid 1980’s in the FAST-CRI-III facility at Oak Ridge National Laboratory to study the transport in sodium of aerosol-bearing UO2 vapor bubbles. Although codes featuring detailed multi-physics models [1] were in various stages of development at the time of program cessation, a simplified thermo-mechanical model, free of requirements for detailed thermophysical property data, has recently been developed for purposes of evaluating FAST outcomes. The model consists of a hydrodynamic module which is used to predict the movement of a pulsatile, aerosol-bearing vapor bubble through the surrounding coolant and a heat transfer module which accounts for thermal interactions as the bubble thermally radiates to the surrounding coolant. The model predictions are consistent with key experimental trends, namely: (1) significantly reduced aerosol release as the coolant level increased, (2) greatly reduced aerosol release in sodium tests compared to release levels measured in a series of baseline water tests. The consistency of these trends is discussed in terms of thermo-mechanical characteristics of the respective coolants. Specifically, the inertia of the surrounding coolant impedes bubble transport to the free surface which addresses the first point above, and, relative to the second point, bubble lifetimes are sufficiently short relative to time estimates for transit to the free-surface, due principally to the effectiveness of quenching by radiation which is particularly pronounced in the case of sodium, owing to high reflectivity values. Additionally, pool subcooling was found to have a cross-cutting influence on aerosol release. Only in tests in which pool subcooling was reduced to ∼10 Kelvin was significant aerosol release detected. For those tests, which occurred in water, measurements suggest that coolant vaporization occurred at intensities above 3000 kg/m2-s, well beyond what has generally been reported from fuel coolant interaction studies in which the coolant interactions are with molten fuel forms. This set of findings will permit a more general assessment of the implications of fuel coolant interactions on the progression of core disruptive accidents, particularly with regards to assessing probable modes of in-vessel aerosol transport within sodium cooled reactors.

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