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Model of Melting and Dripping Thermoplastic Objects in Fire.


pdf icon Model of Melting and Dripping Thermoplastic Objects in Fire. (1060 K)
Butler, K. M.

Fire and Materials 2009. 11th International Conference. Conference Papers. Proceedings. Organised by Interscience Communications Limited. January 26-28, 2009, San Francisco, CA, Interscience Communications Limited, London, England, 341-352 pp, 2009.

Keywords:

thermoplastics; melting; dripping; equations; experiments; flow rate; degradation; computation; temperature; viscosity; heat flux; material properties

Abstract:

A model of the melting and dripping behavior of thermoplastic materials in fire is being developed using the Particle Finite Element Method (PFEM), which is capable of tracking the large changes in shape inherent to this problem in addition to solving the equations of motion and energy. Experiments that approximate two-dimensional flow situations provide a basis for comparison for the model in its early stages of development. Reasonable agreement with experiment has been noted for the quasi-steady flow rate from an upright rectangular object that is heated on one face. The two-dimensional spread rate of the thermoplastic melt that has dripped onto a surface beneath the object has been measured experimentally for both horizontal and slightly tilted catch plates. The model agrees within 10% to experimental results when further degradation of the melt along the catch plate is taken into account.