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The ultrasonic spray technology is studied by the method of theoretical derivation,CFD simulation,spray particle diameter detection and analysis,and experimental analysis. And the ultrasonic spray process for the coating of vascular stent is also optimized. Firstly,the ultrasonic atomization physical model is established and the equation of atomization particle diameter is derived. Secondly,the ultrasonic atomization process is simulated by the CFD method,and shows three atomization patterns:incomplete atomization pattern,critical atomization pattern and jet atomization pattern. The critical amplitude and power equation for ultrasonic atomization is derived. Thirdly,experiment is conducted to study the influence of parameters including power,gas pressure,and surface tension. The results show that the spray is stable though few particles are likely to collide each other during spray moving,and the droplet diameter is about 10-m. The Rosin-Rammler distribution equation for ultrasonic spray is created,and the uniform index number is between 7.11 and 11.48. The uniformity of spray particle diameter,the efficiency of adjustment and the energy consumption are better than traditional spray technology. Lastly,the ultrasonic spray process parameters for stent coating are optimized to eliminate the common defects and obtain fine coating.
The ultrasonic spray technology is studied by the method of theoretical derivation, CFD simulation, spray particle diameter detection and analysis, and experimental analysis. And the ultrasonic spray process for the coating of vascular stent is also optimized. established and the equation of atomization particle diameter is derived. The ultrasonic atomization process is simulated by the CFD method, and shows three atomization patterns: incomplete atomization pattern, critical atomization pattern and jet atomization pattern. Thirdly, experiment is conducted to study the influence of parameters including power, gas pressure, and surface tension. The results show that the spray is stable though few particles are likely to collide each other during spray moving, and the droplet diameter is about 10-m. The Rosin-Rammler distribution equation for ultrasonic spr the uniformity of spray particle diameter, the efficiency of adjustment and the energy consumption are better than traditional spray technology. Lastly, the ultrasonic spray process parameters for stent coating are optimized to eliminate the common defects and obtain fine coating.