Measurements in large pool fires with an actively cooled calorimeter

Conference · Sun Dec 31 04:00:00 EST 1995

OSTI ID:197821

Koski, J A ^[1]; Wix, S D ^[2]

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1. Sandia National Labs., Albuquerque, NM (United States)
2. GRAM, Inc., Albuquerque, NM (United States)

The pool fire thermal test described in Safety Series 6 published by the International Atomic Energy Agency (IAEA) or Title 10, Code of Federal Regulations, Part 71 (10CFR71) in the United States is one of the most difficult tests that a container for larger ``Type B`` quantities of nuclear materials must pass. If retests of a container are required, costly redesign and project delays can result. Accurate measurements and modeling of the pool fire environment will ultimately lower container costs by assuring that containers past the pool fire test on the first attempt. Experiments indicate that the object size or surface temperature of the container can play a role in determining local heat fluxes that are beyond the effects predicted from the simple radiative heat transfer laws. An analytical model described by Nicolette and Larson 1990 can be used to understand many of these effects. In this model a gray gas represents soot particles present in the flame structure. Close to the container surface, these soot particles are convectively and radiatively cooled and interact with incident energy from the surrounding fire. This cooler soot cloud effectively prevents some thermal radiation from reaching the container surface, reducing the surface heat flux below the value predicted by a transparent medium model. With some empirical constants, the model suggested by Nicolette and Larson can be used to more accurately simulate the pool fire environment. Properly formulated, the gray gas approaches also fast enough to be used with standard commercial computer codes to analyze shipping containers. To calibrate this type of model, accurate experimental measurements of radiative absorption coefficients, flame temperatures, and other parameters are necessary. A goal of the calorimeter measurements described here is to obtain such parameters so that a fast, useful design tool for large pool fires can be constructed.

• Research Organization: Sandia National Labs., Albuquerque, NM (United States)
• Sponsoring Organization: USDOE, Washington, DC (United States)
• DOE Contract Number: AC04-94AL85000
• OSTI ID: 197821
• Report Number(s): SAND--95-0082C; CONF-951203--16; ON: DE96003641
• Country of Publication: United States
• Language: English

Related Subjects

05 NUCLEAR FUELS
42 ENGINEERING
44 INSTRUMENTATION
INCLUDING NUCLEAR AND PARTICLE DETECTORS
CALORIMETERS
CALORIMETRY
CONTAINERS
DESIGN
FIRES
FISSILE MATERIALS
HEAT TRANSFER
PONDS
STORAGE
TEMPERATURE MEASUREMENT