Heat loss analysis in a radiating slab of variable thermal conductivity

  • Authors

    • Ramoshweu S. Lebelo
    • Kholeka C. Moloi
    2018-04-20
    https://doi.org/10.14419/ijet.v7i2.23.11924
  • Heat Transfer, Numerical Methods, Radiation, Reactive Slab, Variable Thermal Conductivity.

  • Abstract

    This article investigates the transfer of heat in a stockpile of reactive materials, that is assumed to lose heat to the environment by radiation. The study is modeled in a rectangular slab whose materials are of variable thermal conductivity. The stockpile’s reactive material in this context is one that readily reacts with the oxygen trapped within the stockpile due to exothermic chemical reaction. The study of the combustion process in this case is conducted theoretically by using the Mathematical approach. The differential equation governing the problem is tackled numerically by applying the Runge-Kutta Fehlberg (RKF45) method coupled with the Shooting technique. To investigate the heat transfer phenomena, some kinetic parameters embedded in the governing differential equation, are varied to observe the behavior of the temperature profiles during the combustion process. The results obtained from the temperature profiles, are depicted graphically and discussed accordingly. It was discovered that kinetic phenomena such as the reaction rate parameter, accelerates the exothermic chemical reaction. However, the radiation parameter decelerates the exothermic chemical reaction by lowering the temperature profiles.

     

     

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  • How to Cite

    S. Lebelo, R., & C. Moloi, K. (2018). Heat loss analysis in a radiating slab of variable thermal conductivity. International Journal of Engineering & Technology, 7(2.23), 228-231. https://doi.org/10.14419/ijet.v7i2.23.11924

    Received date: 2018-04-22

    Accepted date: 2018-04-22

    Published date: 2018-04-20