Bounding - h3010v10092

DOE-HDBK-3010-94

4.0 Solids; Summary

Airborne release of particulates formed by self-sustained oxidation (molten

metal with oxide coat), self-induced convection. The phenomena applies to the

self-sustained oxidation in air of metal pieces under self-induced convection.

Mishima's (1965, 1966) values exceed the combined value (ARF x RF) for all

other measurements and are assessed to be bounding for this situation.

Bounding

ARF 5E-4/RF 0.5

Airborne release of particulates from disturbed molten metal surfaces (i.e.,

flowing metal, actions resulting in continual surface renewal), high turbulence

at surface. Without continuous surface renewal, maximum release phenomena

is self-sustained oxidation as described previously. The bounding value applies

to situations where ignited-molten plutonium is disturbed by direct impact of

high air velocities such as during free-fall, induced high turbulence on molten

surface, etc. The 95% confidence limit ARF and RF values recommended by

Carter and Stewart (September 1970) are assessed to bound the experimentally

measured values reported.

Bounding

ARF 1E-2/RF 1.0

This value is also considered applicable to highly energetic surface reaction as,

for example, the conversion of a significant mass of fine hydride to oxide. It

is not, however, applicable to oxidation of trace quantities of hydride as metal

or powder contamination exposed to air.

Airborne release of particulates from oxidation of small (hundreds of m in

diameter) molten metal drops passing through air or explosive reaction of

entire metal mass. For the violent ejection of molten metal and vapor

formation from droplets, Raabe et al. measured an ARF of 1.0 with an RF of

0.4 (estimated from MMD reported) from exploding wire experiments and

Carter and Stewart (September 1970) measured an ARF of 0.5 with an RF of

1.0 for small molten metal drops falling through air.

Bounding

ARF 1E+0/RF 0.5

T h erm al S tress: U ran iu m

Airborne release of particulates during complete oxidation of metal mass,

>500 oC, gas flow 0 - 2 m/s. Based upon the experiments performed by

Carter and Stewart (September 1970) heating uranium in an upflow of air with

oxide generated allowed to sluff away during the oxidation process, the mean

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