Abstract
Solution of inverse problem of heat conductivity for conditions which are of practical interest for boiling of cryogenic liquids inside tubes, the methal representing a generalization of one-dimentional Buggraff method in case of two spatial coordinates is used.
In this paper two-dimentional equation of instable conductivity for a double infinitive cylinder with an ideal heat contact on the interface of two kinds of materials with constant heat physical characteristics. In practice this case is applied to cool down of pipelines with low conductivity coatings by cryogenic liquids.