Method of Calculating Fission Product Mass Transfer in Multizone Reactor Problems

An analytic solution is given for a system of first-order inhomogeneous linear differential equations describing the mass transfer of fission products in radioactive decay chains of arbitrary complexity and length by means of a system of an infinite number of working zones separated by radiation safety barriers. The computational procedure is implemented in the TARUSA system of computer codes, making it possible to take into account the individual behavior of different fi ssion products as they pass through radiation safety barriers and the arbitrary dependence of the basic initial data on the operating time of the reactor. The TARUSA codes possess their own libraries of nuclear-physical constants. A comparison is made with the normative example of the calculation of the residual power release from irradiated fuel from the international standard ISO 10645.