A three dimensional model of a Cold Gas Dynamic Spray system with a peripheral non-axisymmetric powder feeder is studied in this work. It is found that the stagnation pressure alternates for different substrate stand-off distances due to the nature of the supersonic flow interaction with the substrate. One can find the optimum substrate location for any given operating condition which results in minimum pressure buildup on the substrate. The three-dimensional analysis shed more light on the complex gas and particle flow fields generated due to the three-dimensional particle injection process. Additionally, the three-dimensional model allows us to further investigate the effect of practical substrate shapes (such as convex and concave) on the flow field and consequently to determine the optimum conditions to deposit coating particles.