- Author
- Mitler, H. E.
- Title
- Algorithm for the Mass-Loss Rate of a Burning Wall.
- Coporate
- National Institute of Standards and Technology, Gaithersburg, MD
- Book or Conf
- U.S./Japan Government Cooperative Program on Natural Resources (UJNR). Fire Research and Safety. 10th Joint Panel Meeting. June 9-10, 1988, Tsukuba, Japan, 123-124 p., 1988
- Keywords
- walls | combustion | algorithms | enclosures | oxygen concentration
- Abstract
- It is shown in this paper that by using some well-known relationships plus one new result, the quasi-steady mass-loss rate of a pyrolyzing vertical panel of a non-charring, non-melting material (when its vapors are burning), in an enclosure with stratification of temperature and oxygen concentration, can be fairly accurately predicted. The algorithm requires the solution of a transcendental equation. All that is required to be known are the dimensions of the pyrolyzing section, some thermophysical material parameters, any external heat fluxes, the mean flame temperature, and the mean radiation absorption coefficient. the key is the finding (from experiment) that k varies with height; it is well described for PMMA by a two-parameter expression linear in 1/z. In distinction with earlier work, this algorithm is extended to the case where there is strong stratification in the enclosure. Comparison of calculations using this algorithm with a transient experiment yields good agreement for the mass-loss rate over much of the range.