[1] Jia Baoshan, Xie Maozhao,. Numerical study of forward smoldering combustionof polyurethane foam [J]. Journal of Southeast University (English Edition), 2007, 23 (2): 278-284. [doi:10.3969/j.issn.1003-7985.2007.02.025]

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Numerical study of forward smoldering combustionof polyurethane foam()

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Journal of Southeast University (English Edition)[ISSN:1003-7985/CN:32-1325/N]

Volumn:

23

Issue:

2007 2

Page:

278-284

Research Field:

Chemistry and Chemical Engineering

Publishing date:

2007-06-30

Info

Title:

Numerical study of forward smoldering combustionof polyurethane foam

Author(s):

Jia Baoshan¹;  2;  Xie Maozhao¹

¹ School of Energy and Power Engineering, Dalian University of Technology, Dalian 116024, China
² School of Safety Science and Engineering, Liaoning Technical University, Fuxin 123000, China

Keywords:

polyurethane foam;  forward smoldering;  porous medium;  smoldering velocity;  numerical study

PACS:

O642.1

DOI:

10.3969/j.issn.1003-7985.2007.02.025

Abstract:

A two-dimensional and two-phase numerical model is presented for the smolder propagation in a horizontal polyurethane foam.The chemical processes considered include endothermic pyrolysis and exothermic oxidation degradation of polyurethane foam and exothermic oxidation of char.The governing equations are discretized in space using the finite element method and solved by the software package FEMLAB.Predicted profiles of solid temperature as well as evolutions of solid compositions(including foam, char and ash)are presented at an airflow velocity of 0.28 cm/s.The computed average smoldering velocity is 0.021 4 cm/s, and the average maximum temperature is 644.67 K.Based on the evolutions of solid compositions, the packed bed can be obviously divided into four zones:unreacted zone, fuel pyrolysis and oxidation zone, char oxidation zone and fuel burned-out zone.Simultaneously, the effects of inlet air velocity and fuel properties(including thermal conductivity, specific heat, density and pore diameter)are studied on the smoldering propagation.The results show that the smoldering velocity and temperature have a roughly linear increase with increasing inlet air velocity;the fuel density is the most important factor in determining smoldering propagation;radiation has a non-negligible role on the smoldering velocity for larger pore diameters of porous material.The computational results are compared with the experimental data and a general agreement is reached.

References:

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[11] Xie Maozhao, Liang Xiaohong.Numerical simulation of combustion and ignition-quenching behavior of a carbon packed bed [J].Combustion Science and Technology, 1997, 125(1/2/3/4/5/6):1-24.
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Memo

Memo:

Biographies: Jia Baoshan(1972—), male, graduate, associate professor, jiabaoshan72918@sina.com.cn;Xie Maozhao(corresponding author), male, professor, xmz@dlut.edu.cn.

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