SOLUTION OF THE IMPROVED AND GENERALIZED QUASI-STATIC METHODS USING AN ANALYTIC CALCULATION OR A SEMIIMPLICIT SCHEME TO COMPUTE THE PRECURSOR EQUATIONS

The precursors in the point kinetics equations for both improved and g eneralized quasistatic methods are solved using two different methods; an analytic method where the precursors are integrated over the time and a solution given by a semi-implicit scheme. The results obtained b y implementing the semi-implicit method in the TRIVAC-3 reactor code a re very close to those obtained by analytic calculation performed by t he Kaps and Rentrop algorithm for small step size and the total calcul ation time is reduced by approximately one-half.