A detailed model of the electromagnetic pump of the TOPAZ-II space nuc
lear reactor power system is developed and compared with experimental
data. The magnetic field strength in the pump depends not only on the
current supplied by the pump thermionic fuel elements in the reactor c
ore but also on the temperature of the coolant, the magnetic coil, and
the pump structure. All electric and thermal properties of the coolan
t, wall material of the pump ducts, and electric leads are taken to be
temperature dependent. The model predictions are in good agreement wi
th experimental data.