Development of a Model for the Heat Release Rate of Wood. A Status Report.
Abstract
This report describes the status of the development of a method for predicting the heat release rate of wood for different thicknesses, moisture contents, and exposure conditions. A computer program has been set up on a microcomputer. Experimental techniques have been devised to obtain the input data required by the model. These include (1) the thermal conductivity as a function of temperature and percent loss, (2) the kinetic constants needed to describe the mass loss rate, (3) the heat of combustion of the volatile pyrolysis products, and (4) the contraction factors due to charring. Sufficient data on these parameters were taken to exercise the model. Heat release rates and effective heats of combustion were measured as a function of external radiant flux on 12.5 mm thick dry vertical specimens of Douglas fir particle board. The calculated and measured peak heat release rate curves are similar in shape and amplitude but differ significantly in time scale. This may be due to the lack of thermal conductivity data on the char in the high temperature range. There is very good agreement between the calculated and measured effective heats of combustion. The initial results with the model are promising. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- May 01, 1985
- Accession Number
- ADA160275
Entities
People
- W. J. Parker
Organizations
- National Institute of Standards and Technology