Impact of radiation transport on wall loading in fusion reactors

A two-dimensional transport code that calculates the radiation flux as a function of angle and position is used to study the wall loading due to bremsstrahlung radiation from a fusion plasma. This code allows for absorption by the plasma and the wall, as well as for multi (specular) reflection of the photons by the wall. Because the mean free path of bremsstrahlung in fusion plasmas is quite long, absorption by the plasma is shown to be negligible and a limit on the number of reflections experienced by a ray is arbitrarily set to ten or less. For a D-T plasma with impurity in cylindrical geometry a number of interesting cases involving various spatial distributions of the plasma as a whole, the electrons in the plasma, and/or the impurities is examined. We find in the test case, where the plasma and the impurities are uniformly distributed, that the wall loading is uniform and that the flux is peaked at normal incidence