Detailed explanation of ultrasonic atomization knowledge

Compared with the traditional atomizing nozzle, the ultrasonic atomizer is still relatively good, and it will be more environmentally friendly and convenient to use. What is the difference between atomization technology? Next, I will introduce it to you in detail.

Process

The nebulizer uses high-frequency sound waves (beyond the range of human sound sense) to produce the nebulizing function. The disc-shaped piezoelectric ceramic transducer receives the high-frequency electric energy from the broadband ultrasonic generator and converts it into vibration mechanical motion of the same frequency. The two titanium cylinders coupled with the transducer will mechanically vibrate. enhanced. The turbulence formed by the transducer produces a continuous sound wave along the length of the nozzle, and the amplitude of the sound wave is the largest when it reaches the atomization surface, which is the small diameter part at the front end of the nozzle. In general, high-frequency nozzles are smaller in size and produce smaller droplets, while lower-frequency nozzles have lower flow rates. Liquid is directed to the atomizing surface through a large, unobstructed channel along the entire length of the nozzle. The liquid appearing on the atomizing surface absorbs the vibrational energy and is thus atomized.

Nozzle composition

Typical nozzle bodies are made of titanium due to its outstanding acoustic properties, high tensile strength and excellent corrosion resistance. The protective case is made of 316 stainless steel (optionally titanium).

Features of Atomizer

The level of input energy is used to differentiate ultrasonic nozzles from other ultrasonic equipment such as ultrasonic welders, ultrasonic emulsifiers and ultrasonic cleaners. Those ultrasonic devices rely on operating power typically in the hundreds or thousands of kilowatts, but for ultrasonic atomization, input power levels from 1 to 15 watts are generally sufficient.

Atomization spraying uses piezoelectric effect to convert electrical energy into high-frequency mechanical energy to atomize liquid. Ultrasonic high-frequency oscillation is used to atomize the liquid into uniform micron-sized particles. Compared with the traditional pressure nozzle, ultrasonic spraying can obtain a more uniform, thinner and more controllable film coating, and it is not easy to block the nozzle. Since the ultrasonic nozzle only needs a small amount of air in the kilopascal level, there is almost no splash during the spraying process, so the paint utilization rate is as high as 90%.

Additional features

Liquid Delivery Pumps: Ultrasonic nozzles can be used with various liquid delivery systems such as syringe pumps, gear pumps, peristaltic pumps, pressure tanks, etc. Whichever system is used, any of these systems will work as long as the liquid is delivered at a steady flow rate within the operating range of the nozzle. Pulsation should be avoided, however, even momentary pulses may cause the liquid to fall outside the operating range. This is especially noticeable for low flow applications such as stent coatings.

Injection pump

Diversion device: Since droplets usually drift downward under the action of gravity, when installing the atomizer head, the tip of the atomizer head should face downwards to minimize air interference. If directional focusing is required to achieve the desired coating effect, air baffles can be used to direct the airflow. (Under certain conditions, ultrasonic nozzles can be said to be airless systems. Air supply systems are often used to shape the atomizing plume, providing direction and force. In this case, air is used as an auxiliary.)

Advantage

Atomized spraying is a successful technique for applying high-performance and high-quality thin coatings to substrates, for example. Through precise control of various process parameters of ultrasonic atomization, overspray is avoided and precise droplet distribution is achieved. The advantage of ultrasonic atomization is the ability to fully control droplet size, spray intensity and droplet velocity. Industrial Ultrasonic Atomizers Easily Modified Ultrasonic spray drying is a very effective technique without thermal treatment, and due to its mildness, it is very effective on heat-sensitive materials.