Designing a Single Room Ultrasonic Air Humidifier

Project Info


The client who had a small workshop requested us for designing an ultrasonic air humidifier. Common humidifiers add relaxing moisture to dry environments and help maintain a comfortable humidity level. However, contrary to such humidifiers that increase humidity levels in a given room, ultrasonic humidifiers function in a different way. An ultrasonic air humidifier sends a high-frequency vibration to water causing it fast vibrations. Due to its high vibrating frequency, water gets split into smaller droplets which are transformed into vapor. The final result is a clean and sanitized environment.


The requirements for the design included the followings:

  1. Ultrasonic humidification
  2. Room coverage 3×4 sq. m (360 sq. ft.)
  3. Timer
  4. Variable control
  5. Quiet operation
  6. Nightlight


Since the heart of every ultrasonic humidifier is the vibrator that makes the water into droplets, a research was done to find the best option including the actual test with different frequencies, and finally, a piezoelectric transducer that operates at 1700 KHz was chosen. This transducer is capable of creating water droplets with the size of 1-3 microns (0.001 mm).

To make the design an Arduino Nano was used. The electronic part used to create the triggering frequency that was connected to the piezoelectric transducer for creating of vibrations.

The power consumption of the final product was 30W with the humidification of 1.5 L. per 12 hours. Due to its ultrasonic function, the noise level of the product was very low.

Also, adjustable humidity control for the product gave the customer the option to change the output of the air humidifier according to the size of the room.


The final design was done in 2 months and it met all the assigned requirements. The client was satisfied and requested a bigger ultrasonic air humidifier with more capabilities and bigger size.

Russel F.
January 8, 2019
Electrical and Electronic Engineering