One- and two-group diffusion theory for eccentric control rods—I

Abstract

We have solved one- and two-group diffusion equations for a cylindrical homogeneous reactor with an eccentric cylindrical control rod. In the limit of zero eccentricity, solutions in both cases reduce to those corresponding to a cylindrical reactor with a coaxial cylindrical control rod. From this study we find that the control-rod worth decreases as eccentricity increases and, further, that the one-group theory gives higher values compared to the two-group theory.