- Author
-
Cooper, L. Y.
- Title
- Generation Rate and Distribution of Products of Combustion in Two-Layer Fire Environments: A Model and Applications.
- Coporate
- National Institute of Standards and Technology, Gaithersburg, MD
- Journal
-
Fire Safety Journal,
Vol. 23,
245-270,
1994
- Keywords
-
combustion
|
building fires
|
compartment fires
|
computer models
|
fire models
|
mathematical models
|
zone models
|
global equivalence ratio
- Identifiers
- Generalized Global Equivalence Ratio Model (GGERM); Steady State Global Equivalence Ratio Model (SSGERM)
- Abstract
- A model is developed for predicting the generation rates of oxygen, fuel, and any other products of combustion in rooms containing fires and time-dependent fire environments. The model is called the Generalized Global Equivalence Ratio Model (GGERM). It extends the steady state global equivalence ratio model established previously from data of several steady-state experimental studies. After describing the GGERM, a concise algorithm is outlined for implementing it in two-layer zone-type compartment fire models. With the algorithm in place, such models could be used to simulate the distribution of combustion products in single or multi-room fire environments under conditions of arbitrary ventilation. In example applications, the GGERM is used to simulate the time-dependent environment, including that of steady-state, in some of the above-mentioned experimental studies. For arbitrary experimental conditions and for both complete stoichiometric combustion and 'real' combustion of methane (CH₄), solutions for concentration of products of combustion are obtained and presented. For the case of complete stoichiometric combustion, the solutions are used to predict the time-to-extinguishment of a burning CH₄ fuel source embedded in an initially ambient-atmosphere upper layer. In another application, the GGERM is used to simulate the combustion of hexane (C₈H₁₄) in an enclosure fire scenario where data has been reported in the literature. Predicted and measured concentrations of fuel and products are found to compare favorably.