Numerical investigation of CO2 emission and thermal stability of a convective and radiative stockpile of reactive material in a cylindrical pipe of variable thermal conductivity

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.

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Thermal Conductivity Impact on Thermal Stability of Reactive Materials

Diffusion Foundations ◽

10.4028/www.scientific.net/df.11.1 ◽

2017 ◽

Vol 11 ◽

pp. 1-10 ◽

Cited By ~ 3

Author(s):

Ramoshweu Solomon Lebelo

Keyword(s):

Thermal Conductivity ◽

Thermal Stability ◽

Nonlinear Partial Differential Equations ◽

Variable Thermal Conductivity ◽

Spontaneous Ignition ◽

Combustible Material ◽

Temperature Oxidation ◽

Exothermic Chemical Reaction ◽

The Impact ◽

Thermal Stability Of

The impact of thermal conductivity on the thermal stability of a combustible material is studied in a stockpile modelled in a long cylindrical pipe. Two combustible material systems, one with constant thermal conductivity, the other one with variable thermal conductivity, are compared to analyse thermal stability in each case. A combustible material is the one that contains carbons or hydrocarbons that readily react with the oxygen of the system. Low-temperature oxidation or exothermic chemical reaction is the primary cause of spontaneous ignition. This is a theoretical study that involves mathematical approach to do the investigation. The nonlinear partial differential equations for heat transfer are solved numerically using the Finite Difference Method (FDM). Effects of embedded kinetic parameters on the temperature of the system are depicted graphically and discussed accordingly.

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High partial thermal conductivity of luminescence sites: a crucial factor for reducing the heat-induced lowering of the luminescence efficiency

Journal of Materials Chemistry C ◽

10.1039/d1tc02287c ◽

2021 ◽

Author(s):

Ni Luo ◽

Jing Xu ◽

Xiyue Cheng ◽

ZhenHua Li ◽

Yidong Huang ◽

...

Keyword(s):

Thermal Conductivity ◽

Thermal Stability ◽

Practical Applications ◽

Good Thermal Stability ◽

The Past ◽

Luminescence Efficiency ◽

Thermal Stability Of

The good thermal stability of a phosphor is crucial for its practical applications. Unfortunately, in the past decades, only Gurney-Mott equation was available to describe the relation between the luminescence...

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Numerical investigation of the unsteady solid-particle flow of a tangent hyperbolic fluid with variable thermal conductivity and convective boundary

The European Physical Journal Plus ◽

10.1140/epjp/i2019-12651-9 ◽

2019 ◽

Vol 134 (6) ◽

Cited By ~ 17

Author(s):

Madiha Bibi ◽

A. Zeeshan ◽

M. Y. Malik ◽

K. U. Rehman

Keyword(s):

Thermal Conductivity ◽

Numerical Investigation ◽

Solid Particle ◽

Variable Thermal Conductivity ◽

Particle Flow ◽

Convective Boundary ◽

Tangent Hyperbolic Fluid

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Heat loss analysis in a radiating slab of variable thermal conductivity

International Journal of Engineering & Technology ◽

10.14419/ijet.v7i2.23.11924 ◽

2018 ◽

Vol 7 (2.23) ◽

pp. 228 ◽

Cited By ~ 2

Author(s):

Ramoshweu S. Lebelo ◽

Kholeka C. Moloi

Keyword(s):

Differential Equation ◽

Thermal Conductivity ◽

Chemical Reaction ◽

Combustion Process ◽

Variable Thermal Conductivity ◽

Temperature Profiles ◽

Reactive Material ◽

Loss Analysis ◽

Exothermic Chemical Reaction ◽

Rectangular Slab

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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