MICRO AND MESO DAMAGE MODELLING OF ANCHORED REFRACTORY LININGS

摘要

In circulating fluidised bed combustors, the refractory linings anchored to the steel structure (casing) are submitted to important thermal loading which conducts to cracking (due to the difference between the thermal coefficients). A first approach allows to analyse the problem at the anchor scale: a smeared crack model allows to compute the damage which is observed in an experimental test. But since a boiler or a cyclone contains thousand of anchors, it is not possible to compute a complete structure with this model. So, an approach was developed with a two-layer shell equivalent to the anchored lining and the casing. This model was identified with an inverse method, using results from the first approach and validated by a bending test performed on a refractory lining specimen. The damage computing of a structure shows that it is very important to take into account the expansion joints.