Fundamentals of Cleaning With Sound

Acoustic cleaning is the use of low frequency, high-energy sound waves to resonate and dislodge particulate deposits from structural surfaces. Sound is transmitted via the movement of particles in a medium, such as air. Cleaning energy is transferred via a series of compression and tension cycles that create movement in the air to fluidize dust particles that have collected on various surfaces. The acoustic disturbance can be represented as a wave, with the X-axis representing time, and the Y-axis the displacement of a given particle in the medium from its rest position. Once the particulate has been displaced, it is removed by gravity and/or gas flow.

Hertz and decibels

The sound we hear is described by its frequency. Frequency is measured in hertz (Hz), or cycles per second. The general range of hearing humans can detect is between 20 Hz and 20 kHz. The fundamental measurement of loudness is the "BEL" named for Alexander Graham Bell. The decibel (dB) is one-tenth of a BEL.

The decibel is a logarithmic scale of acoustic pressure. In the measurement of sound, the focus is on amplitude of the acoustic pressure, measured in Pascals (Pa) and/or dB. An increase of 10 dB represents a 10-fold increase in sound pressure.

Fundamental Frequency for Cleaning

Acoustic cleaners dislodge particulate by vibrating the particles with sound energy.
  • A certain sound intensity (dB) at a given frequency is required to fluidize particulate
  • Less intensity (dB) is required to resonate particles at lower frequencies (75 Hz to 125 Hz)
  • Larger wavelengths are produced at the fundamental frequencies of 75 Hz to 125 Hz

Thus, an acoustic cleaner that produces an intensity level of 147 dB with a fundamental frequency of 75 Hz can clean a substantially larger area than an acoustic cleaner that generates similar intensity levels (dB) at a fundamental frequency of 230 Hz.

Lower Frequency = Greater Effective Cleaning Area

For More Information

Call: 800-821-2222
GE
8800 East 63rd ST
Kansas City, MO USA