Transient Heat and Reactant Consumption Investigation in a Cylindrical Pipe of Variable Thermal Conductivity

Abstract:

This article investigates the transfer of heat with reactant (oxygen) consumption in a stockpile of reactive material. A reactive material is any carbon or hydrocarbon containing component in a stockpile that readily reacts with the oxygen due to exothermic chemical reaction, where self-ignition may take place if heat generation rate during the combustion process within the stockpile, may exceed the rate of heat release to the surrounding environment. The study is modeled in a long cylindrical pipe whose material thermal conductivity varies with the temperature at a given time. The heat and mass transfer partial differential equations governing the problem were solved numerically using the finite difference method (FDM). Kinetic parameters embedded within the reaction system were analyzed to understand their effects on the temperature and the reactant consumption process. The results shew that the parameters that influence the increase in temperature, increase also the consumption rate of the reactant.

• Periodical: Defect and Diffusion Forum (Volume 392)
• Pages: 178-188
• DOI: https://doi.org/10.4028/www.scientific.net/DDF.392.178
• Online since: April 2019
• Authors: Ramoshweu Solomon Lebelo
• Keywords: Exothermic Chemical Reaction, Finite Difference Method (FDM), Heat Transfer, Oxygen Consumption

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