Acoustic Levitation

The maximum volume of water that can be levitated is primarily determined by the wavelength of the sound used; typically, the droplet's diameter should be less than half the wavelength to maintain stability.

For instance, using a 20 kHz ultrasonic frequency, which has a wavelength of approximately 17 mm in air, the largest stable water droplet that can be levitated would have a diameter of about 8.5 mm, corresponding to a volume of roughly 0.32 milliliters.

Exceeding this size can lead to instability due to the droplet's weight surpassing the acoustic radiation pressure's supportive capacity.

Therefore, while acoustic levitation is effective for small-scale applications, it is currently limited in its ability to suspend larger volumes of water.