THERMAL INSULATION BEHAVIOR OF A MULTILAYER ORTHOTROPIC CYLINDER

The problem of heat conduction in a multi-layer, two-dimensional, orth otropic cylinder subject to asymmetric and periodic temperature distri bution on the outer wall is solved analytically. Dimensional analysis of the problem shows that heat conduction through the cylinder is a fu nction of the Blot number (Bi) and the following four non-dimensional parameters in each layer: frequency ratio (alpha(n)), thickness ratio (x(n)) and radial (K*(r,n)) and tangential (K*(t,n)) conduction rati os. The derivation is valid for an arbitrary number of layers and has been used to study the effect of layer order on inter-layer and overal l heat transfer. A cylinder composed of two layers is discussed as an example. (C) 1997 Elsevier Science Ltd.