Atomkernenergie/Kerntechnik vol. 39 no.4 (1981), p.p. 237-238

The effect of a moderator in the central region of a hollow fuel element as a function of the neutron spectrum composition

Nikos Demetrakopoulos and Demetrios Leonidou
Laboratory of Nuclear Engineering, National Technical University, Patission Street 42, Athens, Greece.

The effect of as hort slowing down length moderator positioned in the central region of a hollow fuel element is investigated as a function of the neutron energy spectrum composition along the axis of the fuel element. The increase of the thermal neutron flux level in all the radial positions of the cell, when comparing the situation with that existing witout a central moderator, is shown to depend on the thermal to epithermal neutron composition of the neutron spectrum in an inverse way.