Influencing factors of ultrasonic spraying
Ultrasonic spraying instrument has a wide range of applications, from interventional medical equipment to the production of solar cells to the manufacture of electronic equipment, everywhere reflects the ultrasonic spraying equipment and pressure spraying, rotary spraying and so on different and excellent. But the application range of ultrasonic spraying equipment is so wide, and the single from spraying this action, many people will think that ultrasonic spraying equipment seems to be omnipotent, in fact, in the same field of ultrasonic spraying use is also different, of course, these different users are unknown, these will be perfected in the design process.
This paper briefly discusses the various influencing factors and the influence characteristics of each factor in the use of ultrasonic spraying equipment in different fields. From the utility of ultrasonic spraying to make a distinction, the main focus is on the two aspects of ultrasonic spraying atomization droplet particle diameter, the second is ultrasonic spraying flow performance.
The key factors affecting the size of the droplet are the vibration frequency of the ultrasonic spraying equipment, the higher the frequency, the diameter of the droplet particles is also about small, followed by the surface tension of the atomized liquid and the density of the liquid also have a certain impact, but generally do not count towards the impact range. Cheersonic research and development of ultrasonic spraying equipment produced by the spray droplets soft, low flow rate of spray, to avoid the use of pressure spraying common excessive spraying phenomenon.
There are four factors influencing the flow performance, namely atomization surface area, orifice size, vibration frequency and liquid properties. The size of the orifice determines the flow size, which is related to the flow rate of the liquid imported into the atomized surface. When the liquid flow rate is too large, the atomization surface will not be able to atomized the liquid, in general, when the low flow rate, the atomization surface of the “attraction” enough to attach the liquid to the surface of the atomized surface, so as to atomization, but the liquid flow rate is too low will appear accidental atomization phenomenon. The atomization surface area is another factor affecting the maximum flow rate, the atomization surface can not only withstand the amount of liquid while at the same time can maintain the ability to produce the film required for atomization has a limit, if the flow is too large, will exceed the atomization surface can retain the ability of liquid film, so that it can not be atomized. The working frequency not only has the image to the atomization particle diameter also has the influence to the flow rate, when the ultrasonic frequency the larger the atomization particle diameter is smaller but the atomization flow is smaller.
In addition to the above ultrasonic spraying equipment itself, the nature of the liquid also has a great impact, first of all, the treatment of liquid into three categories, the first is pure liquid, only contains a single component, such as water; the second category is pure solution, such as saline; the third is a mixture containing solids, such as graphene solution. Usually pure liquid only need to consider the viscosity of the liquid, ultrasonic spraying equipment can handle the maximum viscosity of the liquid is 100CPS; In addition to considering the viscosity of the liquid, the pure solution should also consider whether there is a polymer in the liquid, when the liquid in the atomization surface after ultrasonic separation to form atomized droplets, Polymer molecules will hinder the formation of this discrete droplet; contains solid mixture, mainly considering solid content and solid particle size, solid particle diameter is much smaller than droplet diameter, otherwise the result of atomization is solid-liquid separation, in addition, liquid solid content can not exceed 40%, solid content is too large, will greatly increase the difficulty of atomization.
In a word, the spraying effect affecting ultrasonic spraying instrument mainly has ultrasonic frequency, orifice size, atomization surface area, vibration frequency and liquid properties.