Accession Number : ADA130070

Title :   Pressure Modeling of Char-Forming and Laminated Materials.

Descriptive Note : Final rept. Apr 81-Nov 82,


Personal Author(s) : Alpert,R L

Full Text :

Report Date : Jun 1983

Pagination or Media Count : 114

Abstract : The pressure modeling technique is used to study upward fire spread on fuel wall composed of char-forming or laminated materials. Time-resolved measurements are obtained at one-atmosphere (full-scale) and at elevated air pressure (model scales) to characterize fire growth in terms of rate of total mass loss, flame height, upward flame spread rate, and maximum lateral flame dimensions during the spread process. The char-forming materials (pine-wood, particular-board and a rigid, polyurethane foam) are tested in a 90deg. wall-corner configuration while the laminated materials (PMMA in combination with PMMA or ceramic backings) are tested in a wall configuration. Thermally-thick PMMA is tested in both configurations for purposes of comparison. Results are generally consistent with the pressure modeling scheme and a series of one-dimensional, transient thermal conduction and pyrolysis calculations. The behavior of the rigid polyurethane foam, however, is an exception. This material does not support self-sustained upward flame spread at one-atmosphere when exposed to flames from a 0.1 m high PMMA ignition source but does not support rapid fire growth at elevated pressures. A possible reason for the anomalous polyurethane behavior is the intumescent structure of the hot char at one-atmosphere, but a better understanding of the mechanism of upward or wind-aided flame spread on charring materials is needed to resolve the issue.

Descriptors :   *Composite materials , *Laminates , *Flammability , *Burning rate , Pressure measurement , Flame propagation , Thermal analysis , Thermal conductivity , Heat flux , Fires , Pyrolysis , Walls , Behavior , Ignition , Tables(Data)

Subject Categories : Laminates and Composite Materials
      Wood, Paper and Related Forestry Products
      Test Facilities, Equipment and Methods

Distribution Statement : APPROVED FOR PUBLIC RELEASE