A 3-D Direct Simulation Monte Carlo (DSMC) code has been developed to study the vapour characteristics of atomic species. This model needs to be verified with experimental results. Experiments have been conducted with free jet of copper using electron beam source and the flux distribution data have been obtained under different experimental conditions. For better statistics, the Direct Simulation Monte
Carlo (DSMC) code was parallelised to run on parallel system. The experimental results from circular and a slit source (Kn varies from 0.47 to 0.083) have been compared with Direct Simulation Monte Carlo (DSMC) results. The results have shown excellent agreement. From the trend of the flux distribution curves, it is clear that with lower Kn, more uniform coating can be expected.