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Users' Guide to BREAK1, The Berkeley Algorithm for Breaking Window Glass in a Compartment Fire.

Users' Guide to BREAK1, The Berkeley Algorithm for
Breaking Window Glass in a Compartment Fire.
(1055 K)

Joshi, A. A.; Pagni, P. J.

NIST GCR 91-596; 27 p. October 1991.

### Sponsor:

National Institute of Standards and Technology,
Gaithersburg, MD

### Available from:

National Technical Information Service

Order number: PB92-112556

### Keywords:

computer models; fire models; glass; mathematical
models; radiation; thermal stresses; vents; thermal
conductivity; thermal diffusivity

### Abstract:

*
This is an instructional manual for the computer program
BREAK1, the Berkeley Alogorithm for Breaking Window
Glass in a Compartment Fire, version 1.0. The thermal
response of window glass exposed to a compartment fire
and its time to breakage are calculated. The following
glass properties, treated here as constant, are required
as input: thermal conductivity, thermal diffusivity,
absorption length, breaking stress, Young's modulus,
coefficient of linear thermal expansion and emissivity.
In addition, the ambient temperature, the hot layer
temperature, heat transfer coefficients and emissivities
and the direct flame radiation histories are needed as
input. The window geometry is also required. The
output describes the evolution of the window temperature
field, T(x,t), where x is the direction normal to the
glass pane, culminating in the window breakage time.
This manual contains a summary of the mathematical
model, sample thermophysical and mechanical data tables,
some worked examples and advice on using the program.
*