ON A VARIATIONAL PRINCIPLE FOR REACTION RADIATION/CONDUCTION EQUILIBRIA/

The generalized Semenov/Frank-Kamenetskii problems which govern the st eady couplings between radiation/chemical heat-release and conduction are shown to be deducible from a variational principle whatever the sh ape of the reacting body, at least when the latter has a convex outer surface and radiation follows an Eddington-like law specialized to gre y properties. A few examples are given to illustrate how this can be e xploited in practical situations.