Improved lumped models for transient heat conduction in a slab with temperature-dependent thermal conductivity

This work reports improved lumped-parameter models for transient heat conduction in a slab with temperature-dependent thermal conductivity. The improved lumped models are obtained through two point Hermite approximations for integrals. For linearly temperature-dependent thermal conductivity, it is shown by comparison with numerical solution of the original distributed parameter model that the higher order lumped model (H1;1=H0;0 approximation) yields significant improvement of average temperature prediction over the classical lumped model. A unified Biot number limit depending on a single dimensionless parameter b is given both for cooling and heating processes.Indisponível

Improved lumped models for combined convective and radiative cooling of a wall

Improved lumped parameter models are developed for the transient heat conduction of a wall subjected to combined convective and radiative cooling. The improved lumped models are obtained through two point Hermite approximations for integrals. It is shown by comparison with numerical solution of the original distributed parameter model that the higher order lumped model (H1;1=H0;0 approximation) yields significant improvement of average temperature prediction over the classical lumped model.Indisponível