To investigate the thermal and dynamic behaviors of in-flight particles in plasma flow the velocity and temperature before impinging plate
and the trajectories of particles injected by inner channel are analyzed for whole supersonic plasma flow
the actual in-flight particles are on-line monitored by SprayWatch-2i. Numerical test result indicates that both particle velocity and temperature achieve the maximum at the distance of 80~100 mm
which coincides with the status of observed individual particle in the experiments. So this range of 80~100 mm can be taken as the best spraying distance. According to the analysis for Weber number and velocity distribution of particles with small diameters
particles are melted and refined inside the gun or near the gun exit in internal powder injection supersonic plasma spray
which supports the experimental results on heat and mass transfer of particles.
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