Prediction of Particle Velocity for the Cold Spray Process
Final rept. Apr 2009-Sep 2010
ARMY RESEARCH LAB ABERDEEN PROVING GROUND MD WEAPONS AND MATERIALS RESEARCH DIRECTORATE
Pagination or Media Count:
The ability to predict particle velocity is key to the prediction of cold spray performance. Individual particles must exceed a material dependent critical velocity in order to deposit and form a coating. Particle velocities can be calculated from the drag relationship between the particle and flowing gas. The relative accuracies of a one-dimensional 1-D calculation vs. a twodimensional 2-D calculation, in comparison to measured values, would help determine whether the simple 1-D calculation can be used instead of the more complicated 2-D calculation. Both types of calculation were performed for a given nozzle and compared with measured values. It was found that the 1-D calculation resulted in velocities about 7 higher than measurement, while 2-D calculations yielded velocities 7 lower than measured values. The 2-D calculation yields more information, but the fast, convenient 1-D calculation has adequate information and accuracy to be used for most particle velocity calculations.
- Pumps, Filters, Pipes, Tubing, Fittings and Valves