Application Cases

Experiment Name: Application of Power Amplifier in Research on the Ultrasonic Atomization Effect of Citriodora Oil Mosquito Repellent Liquid Using Microhole Piezoelectric Atomization

Experiment Objective:
To address the issues associated with commonly used manual pressure atomization for citriodora oil mosquito repellent liquid, such as large droplet size and the inability to perform continuous, automatic spraying, a microhole piezoelectric ultrasonic atomization method is proposed. This method atomizes the repellent liquid into micron-sized droplets, allowing them to remain airborne for extended periods, thereby enhancing the mosquito-repellent effect of citriodora oil.

Experimental Equipment:
Citriodora oil mosquito repellent liquid, laser particle size analyzer, microhole piezoelectric ultrasonic atomizer, test lifting table, signal generator, ATA-4014 high-voltage power amplifier, oscilloscope, electronic balance

Experimental Procedure:
The electrical signal generated by the signal generator is amplified by the power amplifier and then applied to excite the atomizing vibrator, which produces ultrasonic vibrations. These vibrations deform the microhole piezoelectric atomizing plate, causing the liquid in contact with the microholes to be extruded through the plate due to inertia, surface tension, and fluid dynamic forces. The driving voltage frequency can be changed by adjusting the output signal frequency of the signal generator. The driving voltage amplitude can be altered by adjusting the output signal amplitude of the signal generator or the amplification factor of the power amplifier.

Figure: Schematic Diagram of the Experimental Principle

Experimental Results:

1. Influence of atomizer plate aperture on atomization effect:
   Under constant driving voltage and rated operating frequency of the atomizer, the atomization rate increases linearly with the increase in the aperture of the atomizer plate.

2. Influence of driving voltage on atomization effect:

   

   Figure: Influence of driving voltage on atomization effect

3. Influence of driving frequency on atomization effect:

   

   Figure: Influence of driving frequency on atomization effect

4. Comparison of atomization effects between pressure atomization and microhole piezoelectric ultrasonic atomization:

   

   Figure: Comparison of atomization effects between pressure atomization and microhole piezoelectric ultrasonic atomization

Experimental Conclusion:
The experimental results show that under the same driving voltage and frequency conditions, the droplet size and atomization rate increase linearly with the increase in the microhole diameter of the atomizer plate. For the same atomizer plate aperture, changing the driving voltage or frequency causes the droplet size and atomization rate to first increase and then decrease, exhibiting a peak value. When the aperture is 13 μm, the driving frequency is 108 kHz, and the driving voltage is 90 V, the droplet size is 15.13 μm, which is only 27.95% of that achieved with manual atomization. The atomization rate is 0.06 g/min, allowing for continuous, automatic spraying. The research results can provide a reference for the design of microhole piezoelectric ultrasonic atomizers for citriodora oil mosquito repellent liquid.

Figure: Specifications of ATA-4014C High-Voltage Power Amplifier