Numerical analysis of heat conduction in granular geo-material using lattice element method

摘要

Heat transfer in geo-materials especially in granular systems is important to a vast array ofrnpractical problems, yet is poorly understood even in the simplest case, such as conduction in dry state. This isrndue in part to the stress and contact heterogeneities inherent to these systems. Heat conduction in a packet bedrnis analyzed computationally based on lattice element method.rnA novel model is developed based on the Lattice Element Method, which not only sheds light on fundamentalrnissues in heat conduction in particles, but also provides a valuable test bed for existing theories. By meshing therndomain the material heterogeneity is directly included, and thus dynamic temperature distributions are obtainedrnat the particle level. Comparison with existing experiments shows that this model yields a quantitatively accuraterntemperature field without the need for adjustable parameters or detailed microstructural information. This simplernsystem is suitable for providing insight into such phenomena as reactor and underground energy and steam cablern“hot spot” formation and spontaneous combustion of bulk reactive materials.