Effect of a varying effective thermal conductivity term on heat conduction through a physical model of a hydride bed

This paper investigates the effect of implementing a varying effective thermal conductivity term on heat transfer simulations within a metal hydride (MH) reactor. The work presented utilises a 1D transient heat transfer analysis comparing simulations either with a fixed effective thermal conductivity or a varying effective thermal conductivity. This builds on previously published work in the literature that has investigated varying effective thermal conductivity for metal hydrides at a single point. The results of these simulations are compared to experimental work for validation.The 1D simulation results clearly show that the varying effective thermal conductivity term more closely matches experimental results compared to the fixed effective thermal conductivity term. The results show that whilst a 1D simplification within the model may be valid in a bed some distance from the heating source, there are issues close to the heating source. It is speculated that neglect of losses outside of the 1D assumption are the cause of these issues.

► A varying term for effective thermal conductivity is used to model heat transfer.
► Simulations using fixed and variable effective thermal conductivity are compared.
► The use of a varying thermal conductivity term improves simulation accuracy.
► The limitations of 1D modelling in heat transfer in a packed bed are demonstrated.