Do You Understand Acoustic Attenuation in Ultrasonic Level Meters?

In air, the acoustic attenuation of the ultrasonic level meter from Dayu Electronics is generally caused by the following three factors:

　　1. Absorption attenuation: The viscosity, thermal conductivity, and various relaxation processes of the medium lead to sound absorption.

　　2. Scattering attenuation: When sound waves encounter obstacles composed of another medium during propagation, they scatter in different directions, causing a reduction in sound intensity. This phenomenon is collectively referred to as scattering attenuation.

　　3. Divergence attenuation: The reduction in sound intensity caused by the expansion of the wavefront area during propagation. Because sound waves experience these attenuation phenomena during propagation, a single transducer cannot measure distance without limits. To increase the measurement range, the sensitivity of the transducer must be improved and sound attenuation must be reduced. Absorption attenuation is determined by the propagation medium, while divergence attenuation is determined by the transducer and the propagation distance. Scattering attenuation is related to frequency: the lower the frequency, the smaller the scattering attenuation. The cleaner the air, the smaller the scattering attenuation. Therefore, when measuring large ranges, we generally use low-frequency ultrasound. Additionally, in dusty environments, the full range cannot be used.