A hybrid computational method for dynamic thermal analysis of structures including thin layers

Thin layers in the context of transient phenomenon appear in many applications in the field of aeronautics and space. Examples for such applications include external thin coatings of bare panels which are exposed to the periodic solar radiation, and the thin glue layer that connects the complex parts in a plane or satellites. Usually there are two different and extreme approaches to handle the modelling and analysis of such thin layer. The first is to ignore this layer and the second is to fully model it using FEM for example. The first can suffer from severe inaccuracy, and the latter is time consuming and expensive. Among other methods, unique asymptotic models were developed to deal with thin layer modelling. In which the thin layer is replaced by an interface with zero thickness, and special jump conditions are being dictated on this interface in order to express the special effect of the layer. The present work shows how the first-order asymptotic interface model proposed by Bövik P. in 1994, and later generalized by Benveniste Y., can be incorporated in a FE formulation, to yield an accurate and efficient computational scheme for problems involving thin layers. This is done here for linear scalar parabolic problems in two dimensions, prototyped by transient heat conduction, using numerical examples to show that the proposed scheme is more cost-effective than fully modelling the layer.