Reactor Kinetics with Surface Perturbation

Abstract

The reactor kinetics with the surface deformation of an outer reflector was solved by a perturbation method.
Although the spacial reactor kinetics has been discussed by many authors on the different standpoints, we can not apply them directly for our present purpose. Here, a diffusion equation was transformed into an integral equation to obtain the time components of the neutron flux corresponding to surface deformations. As compared with the ordinary perturbation such as the insertion of a poison, in which the outer boundary of the reactor is fixed, we have to treat the extra terms besides the main source term of a surface integral. As examples, five cases of surface deformations were treated and the corresponding neutron flux responses were derived for the one-dimensional slab reactor.
The method studied here is applicable directly to a multigroup diffusion model.