INPUT DATA OF BURNING WOOD FOR CFD MODELLING USING SMALL-SCALE EXPERIMENTS

• Main Authors: Petr Hejtmánek, Libor Ševčík, Kamila Cábová
• Format: Article
• Language: ces
• Published: Czech Technical University, Prague 2017-12-01
• Series: Civil Engineering Journal
• Subjects: Combustion of wood; Pine; FDS; Cone calorimeter; FTCH; Small-size experiment
• Online Access: http://www.civilengineeringjournal.cz/archive/issues/2017/2017_4/4-2017-0038.pdf

The paper presents an option how to acquire simplified input data for modelling of burning wood in CFD programmes. The option lies in combination of data from small- and molecular-scale experiments in order to describe the material as a one-reaction material property. Such virtual material would spread fire, develop the fire according to surrounding environment and it could be extinguished without using complex reaction molecular description. Series of experiments including elemental analysis, thermogravimetric analysis and difference thermal analysis, and combustion analysis were performed. Then the FDS model of burning pine wood in a cone calorimeter was built. In the model where those values were used. The model was validated to HRR (Heat Release Rate) from the real cone calorimeter experiment. The results show that for the purpose of CFD modelling the effective heat of combustion, which is one of the basic material property for fire modelling affecting the total intensity of burning, should be used. Using the net heat of combustion in the model leads to higher values of HRR in comparison to the real experiment data. Considering all the results shown in this paper, it was shown that it is possible to simulate burning of wood using the extrapolated data obtained in small-size experiments.