Estimated Temperatures - std301320040068

DOE-STD-3013-2004

at 950C. The heavy line that passes through the data points is a statistical regression, and is

given by the relationship

Fp = 0.2348 + 0.05673 ρbulk

[27]

Where Fp is the density ratio, and ρbulk is the bulk density. The standard error of an estimate

made using this regression is approximately 0.079. A "bounding" estimate can be made by

adding twice the error to the estimate. That is shown in Figure B-2 by the dashed, lighter

weight line that is above all the data points.

B.3.3

Estimated Temperatures

The final parameter required for use of Equation [25] is the gas temperature. As it is impractical

to measure this quantity, it is necessary to calculate it. In this appendix, we are only interested

in providing guidelines for use of Equation [23], and so will use "worst case" temperatures that

might be encountered. Calculations at the Savannah River Site by Hensel for a configuration in

which a storage package generating 19 w is placed in a 9975 transportation package indicate an

average gas temperature of approximately 164C for normal storage conditions in an ambient

temperature of 37.8C (100F) (see Table A-1). These calculations also indicate an average gas

temperature of approximately 211C for transportation conditions (exposure to solar heating).

These temperatures are probably bounding and may be used when other information is not

available. Each storage facility should evaluate average gas temperatures under the conditions

anticipated at that facility, such as loss of cooling events, to determine appropriate evaluation

conditions.

B.3.4

Example Calculations

B.3.4.1

Example Pressure Calculation for Weapons Grade Oxide

Assume that a BNFL container will be loaded with 5.0 kg of weapons grade oxide that has a

density of 10 kg/l (and is therefore assumed to be fairly pure) and a moisture content of

0.5 wt%. The package was loaded at 86F (30C), and could encounter conditions in the

storage vault in which the gas temperature might reach 400F (204.4C). The heat generation

rate is 2.8 w/kg times 4.4 kg of Pu, or 12.4 w. The evaluation temperature is 204.4 + 273 or

477.4 K, and the loading temperature is 30 + 273 or 303 K. The values of the parameters used

in the pressure equation are summarized in Table B-3.