PUSONICS has developed ultrasonic atomizers with vibrating plate transducers able to treat flows of about 1000 m3 /h with drops size ranging from 20 to 100 microns and energy consumption of 0.25 kWh/m3. The liquid is supply without pressure over the vibrating plate radiator of the transducer.
ULTRASONIC ATOMIZATION BY PLATE TRANSDUCERS
The disintegration of a liquid into fine droplets in a gas is known as atomization. Ultrasonic vibrations are able to produce atomization of liquids into very fine droplets difficult to obtain by conventional nozzles.
The main mechanisms involved in ultrasonic atomization are the formation of capillary waves and the production of cavitation. Capillary waves have a direct influence on the size of the droplets while cavitation produces the shocks to break the liquid layer with ejection of the droplets.
The ultrasonic atomizers of PUSONICS, initially developed by the scientific group (from the Spanish Higher Council for Scientific Research, CSIC) founder of the company, are based on the specific plate transducers manufactured by the company. They involve as main performance, in addition to the typical more uniform droplet size distribution of the ultrasonic atomizers, the capacity of atomizing large volumes of liquid
- Drop means size of 100 microns with a frequency of 21 kHz can be obtained at a flow rate of 1m3/h Smaller drops can be generated with slower flows and/or higher frequencies.
There is no air pressure, no erosion, no clogging.
Flows of 1m3/h per each ultrasonic unit are difficult to attain by the conventional ultrasonic atomizers, therefore these new devices are more appropriate for industrial scale applications. In addition, it is possible to design specific units for higher volumes
Low energy consumption in the range of 0.25-0.5 kWh/m3 that can be reduced working in vacuum.
Atomization can be a complementary technology to another drying, evaporation or distillation process in production lines. This new ultrasonic atomization technology, may be used in a large field of applications, such as water desalinization, powder milk manufacture, spray drying, waste water treatments, fuel injection in combustion etc.
You can see an example of prototype at: http://www.youtube.com/watch?v=TQ1L0588zy8