Model of Neutral-Beam Propagation in a Duct With Scrapers

A model of propagation of a neutral beam with geometric focusing and angular divergence in a duct is described. An algorithm is presented for calculation of a 2-D current-density profile at an arbitrary distance from a flat circular emitter with the account of multiple plane scrapers in the beam duct, which limit cross section of the beam. Numerical code is applied to calculation of current-density profiles and power loads on circular scrapers due to neutral particles.