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Cold spray is a technique to make a coating on a wide variety of mechanical or electric parts by spraying solidparticles accelerated through a high-speed gas flow in a converging-diverging nozzle.In this study,pseudo-shockwaves in a modeled cold spray nozzle as well as high-speed gas jets are visualized by schlieren technique.Theschlieren photographs reveals the supersonic flow with shock train in the nozzle,Static pressure along the barrelwall is also measured.The location of the head of pseudo-shock wave and its pressure distribution along the noz-zle wall are analytically explained by using a formula of pseudo-shock wave.The analytical results show that thesupersonic flow accompanying shock wave in the nozzle should be treated as pseudo-shock wave instead of nor-mal shock wave.
Cold spray is a technique to make a coating on a wide variety of mechanical or electric parts by spraying solid particles accelerated through a high-speed gas flow in a converging-diverging nozzle.In this study, pseudo-shockwaves in a modeled cold spray nozzle as well as high-speed gas jets are visualized by schlieren technique.Theschlieren photographs reveals the supersonic flow with shock train in the nozzle, static pressure along the barrelwall is also measured. location of the head of pseudo-shock wave and its pressure distribution along the noz-zle wall are analytically explained by using a formula of pseudo-shock wave. The analytical results show that thesupersonic flow accompanying shock wave in the nozzle should be treated as a pseudo-shock wave instead of nor-mal shock wave.