Solving nodal kinetic equations by using a global reactivity way

Computation codes which can analyze accident and transient cases sufficiently accurate and fast should be developed for safely operation of nuclear power and research reactors. Nodal kinetics is one of the computation methods which deal neutron dynamics in the reactors fast, accurately and in detail. In the calculation of the coupling reactivity, a convergency matter may arise depending on the problem being handled and so solving of the nodal kinetic equations may get in trouble. This situation is ousted by using a global reactivity way. In this solution technique, first, a neutron flux profile is computed by using the global reactivity calculated from the regional parameters in the nodal kinetic equations. Then, this flux profile is adjusted according to the coupling reactivity of each region. As a result, convergency problem in determining the coupling reactivity and limitations on computation time interval and nodal sizes dismiss and so an accurate neutron flux profile is fast calculated without any problem.