Application of The Nodal Mixed Dual Technique of Spatial Reactor Kinetics Using the Improved Quasi-Static Method

The mixed dual nodal method MINOS is used to solve the reactor kinetics equations in the improved quasi-static IQS context. The speed of calculation which is the main advantage of the MINOS method and the possibility to take the large time step for shape flux calculation allowed by the IQS method, allow us to reduce considerably a time of calculation. The IQS/MINOS method is implemented in CRONOS 3D reactor code. Numerical tests on large light water reactor transient model show that the results obtained with the IQS/MINOS method and the direct numerical method used to solve the kinetics equations, are very close and the total calculation time is largely reduced. (author)