There is a great amount of process parameters influencing the quality and consequently the mechanical behaviour of thermally sprayed coatings. The thermodynamical conditions of sprayed particles before impact onto the substrate material have probably the greatest effects on the coating formation. Completely different coatings are formed depending on the sprayed material, the powder size distribution, the percentage of molten material in a particle and the particle dynamics. Whenever a new coating system is developed or if an already established system is modified in order to obtain different coating properties, enormous experimental efforts have to be overcome to produce the requested coating. One way to bypass these troubles is to apply numerical modelling to analyse the particle properties depending on process parameters of the system. As a first approach a model has been developed to predict the velocity and temperature distributions in an atmospheric plasma jet. The gas-particle interactions due to the drag forces are modelled in order to investigate the movement of the particles in the free jet.