| THERMAL ENGINEERING |
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Numerical simulation method and experimental validation of a single char particle combustion model in bulk space |
| LIU Yuting, HE Rong |
| Key Laboratory for Thermal Science and Power Engineering of Ministry of Education, Department of Thermal Engineering, Tsinghua University, Beijing 100084, China |
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Abstract A numerical method is developed based on the conservation equations for multicomponent reacting systems to better predict char particle combustion. The advantage of this method is that many physical and chemical processes occurring in the char particle boundary layer are described in detail with less CPU time, which improves the studies of the char combustion mechanism. This method can also be used to simulate real situations with relatively simple flow patterns, like the char particle combustion in a drop tube furnace (DTF). Four chars are combusted in a DTF with their final conversions measured. The predicted char conversions compare well with the measured data to validate this method. As the ambient temperature increases, the char combustion rate becomes faster and the O2 concentration decreases while the CO and CO2 amounts strongly increase in the char particle boundary layer.
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| Keywords
char combustion
simulation
conservation equation
drop tube furnace
experimental validation
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Issue Date: 15 June 2016
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2016,
Vol. 56
