9.17.

In reactor cooling problems, it is often of interest to estimate the maximum heat-generation rate (or power density) at a point in a given fuel channel, rather than for the whole reactor core. In equation (9.1), the first (Bessel function) term gives the radial flux distribution, whereas the second (cosine) term represents the axial distribution in a cylindrical re­actor. In any specified axial fuel channel, at a fixed radial distance r from the reactor center, the neutron flux distribution is

where (фщах)ахіаь the maximum flux at the center of the given channel, is equal to ;фтах/о(2.405г/Я’).

9.19.

The result expressed by equation (9.5), or the simplification for the core without end reflectors, is also applicable to fuel channels in a rectangular parallelepiped reactor. For this geometry, the flux distribution in any direction parallel to one of three principal axes is represented by an expression analogous to equation (9.4). The only change necessary is to replace H by the actual length of the reactor core in the given direction, and Я’ by the effective length including allowance for the reflector.