- of sound propagation in water;
- of ultra-sound in liquid environment;
- of noise in moist and polluted environments;
- of sound in liquid and gaseous environments (for laboratory and factory use).
of broadband hydrophones ZET 321 (ВС 321)
for threaded hydrophone ZET 321 (BC 321)
The hydrophones should be installed in special mounting areas (transition adapters, hot tapping, etc.).
The hydrophone should be installed into the mounting area with the use of wrench and hexagonal section of the measurement unit. Other parts of the hydrophone should not be used for installation purpose.
In order to secure hermeticity of hydrophone installation, it is necessary to use the sealing end (copper gasket), which is included into delivery scope. It is undesirable to use other types of end sealing (e.g., foam tape, flax fiber, etc.), since these types of sealing are not able to provide the required level of hermeticity.
Example of threaded hydrophone installation
of the broadband hydrophones ZET 321 (ВС 321)
Operation of hydrophones in the mode of signals receipt and emission
The below graph shows the AFR of hydrophone ZET 321 in the signal receipt mode.
of the broadband hydrophones ZET 321 (BC 321)
The hydrophone is represented by piezo-electrical transducer with the sensing element made from ceramic piezo-electrical materials. The sensing element and its inner bearing structure are firmly fixed inside of sound-proof package (duprene rubber is used as the material of the package). The main casing is made of stainless steel, which is resistant to corrosion, negative environmental impact, and can also be used in seawater. All steel components of the hydrophone have the required protection.
Hydrophone ZET 321 has smooth frequency response curve throughout the entire frequency range in the case if it is used in homogeneous environment (including air, sea and fresh water).
Acoustic communication is an important component in the life of the cetaceans. Noise pollution of the ocean (sonar systems, underwater explosions, and water traffic) is the main reason of marine mammals population reduction, since the noise negatively affects hearing system of the cetaceans. Broadband hydrophones ZET 321 (BC 321) can be used as a primary transducer of acoustic pressure in measurement and recording systems for marine mammals research.
Acoustic detection devices based on the use of hydrophones ZET 321 allow to find the exact location of vocalizing marine mammals as well as to record the sounds produced by dolphins and whales.
This method can be considered to be the most ecologically safe one, since the acoustic detection devices located on the seabed do not disturb the marine animals, while the data obtained with the use of such systems is quite sufficient for exact detection of the sound source location.