Buoyancy Effects on Cooling a Heat Generating Porous Medium: Coal Stockpile

In this study, the effects of buoyancy on heat and fluid flow within and around a coal stockpile are numerically investigated by both a FORTRAN code and the commercially available CFD-ACE software. Numerical simulations are backed up by theoretical results based on scale analysis. Transient variation of maximum temperature inside the coal stockpile is monitored for different coal properties. Besides, the effects of reduction of the stockpile porosity on the prevention of self-heating are studied. In doing so, on top of numerical results and as an independent prediction tool, Bejan’s Intersection of Asymptotes method is applied to find the optimum porosity of the stockpile. Finally, the energy flux vectors are used to track the correct path of energy transportation in the computational domain.

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