Views:0 Author:Site Editor Publish Time: 2019-03-11 Origin:Site
Transducing materials and acoustic materials:
PZT piezoelectric ceramics are developing towards industrialization. So far, lead zirconate titanate (PZT) piezoelectric ceramics have been used as water.The transducer material of the acoustic transducer still dominates. PZT piezoelectric ceramics developed by China Institute of Acoustics, commonly used models are PZT-4 (transceiver and dual-use), PZT-5 (receiving type) and PZT-8 (high-power emission type), and their performance can meet various underwater sounds. The needs of the transducer are compared to those of foreign countries. Transducing materials and acoustic materials Piezoelectric ceramics are developing towards industrialization.So far, lead zirconate titanate (PZT) piezoelectric ceramics still ranks first as the energy-transducing material for underwater acoustic transducers. PZT piezoelectric ceramics developed by China Institute of Acoustics, commonly used models are PZT-4 (transceiver and dual-use), PZT-5 (receiving type) and PZT-8 (high-power emission type), and their performance can meet various underwater sounds. They are needs of the cylinder ceramic transducer, its level and the foreign phase piezoelectric piezoelectric d33 is measuring instrument developed in the piezoelectric ceramic measurement,which has been promoted more than 100 domestic,and edited the standard National Standard for Static Piezoelectric Strain Constant Measurement Method.Hydroacoustic materials mainly include sound absorption, anti-sound, sound and sound insulation materials, vibration damping materials and other research content. In this respect, the company has established the first underwater acoustic pulse tube test equipment, Fuyang's modulus and complex shear modulus test equipment, and is equipped with variable temperature and pressure device and microcomputer data processing system and high acoustic characteristics measurement system. In the field of sound absorbing materials, two kinds of water have been developed.They are acoustic sound absorbing material and three kinds of sound absorbing structure: flat cusp parallel channel type, square cusp and flat resonance type, which can meet the requirements of different frequency bands. The flat sound absorption tip has been widely used in the large and medium-sized muffler pools in China, and the sound pressure reflection coefficient is less than 10% in the frequency range of 8 to 100 kHz. In addition, T801 ~ T808 type sound-permeable rubber, cast type room temperature vulcanization, high-frequency sound absorption and sound-permeable materials, high sound absorption lining, sound absorption damping and putty type damping materials have been widely used in various engineering projects.Ultrasound simulation module series and ultrasonic simulation module series developed by ultrasonic human body tissue is the medical ultrasonic diagnostic instrument detection standard confirmed by the State Bureau of Technical Supervision and the State Administration of Medicine.
Hydroacoustic transducer and array:
The most commonly underwater acoustic transducers are flat piston type, longitudinal vibrator horn type, round calibration type and curved type. China can design and manufacture various piezoceramic cylinder ceramic transducer that meet the needs of engineering, and the level is comparable to that of foreign countries.
(1) High-power transmitting transducer
The high-density emission transducer (inlaid cylindrical transducer) of the ring is obtained, and the scientific and technological achievements of the Chinese Academy of Sciences are obtained. Among them, the "piezoelectric ring electrode" has obtained the utility model patent. The transducer is the first deep sea broadband in China. The high-power underwater acoustic emission transducer is used for sea-water exploration of the sea area. The technology has been successfully applied in acoustic systems such as underwater acoustic receivers, underwater positioning speedometers and analog targets.
(2) bending transducer
The vibration and sound radiation of the lantern-type flexural transducer were studied and analyzed by the finite element method, and the results have been widely applied to sonar equipment. Based on this, a concave bending transducer was also studied. Compared with the existing convex lantern-type bending transducers in the world, this transducer has higher sensitivity and volumetric speed, and is resistant to static pressure. In particular, this structure can achieve high broadband by using multimode vibration. The characteristics are highly praised by foreign water acoustic.
(3) Research on piezoelectric composite piezo ceramic tube and rock transducer using PZT (3-3) sandwich composite piezoelectric material, the piezoelectric constant gh value is high and the figure of merit dh × gh is large and the vibration mode is better. Simple, and easy to match the characteristics of rock mass developed into broadband high sensitivity hydrophone and broadband narrow pulse rock ultrasonic transducer.
Hydroacoustic transducer array:
(1) "202" noise ranging plane array, which has the characteristics of frequency bandwidth, high sensitivity and good reliability piezoelectric tube piezoelectric transducer.In the frequency band of 10 kHz, the phase difference between the elements is not more than ±3°, and the amplitude difference is not more than ±1 dB.
(2) Towed line array. The towed line hydrophone array developed by this sonar consists of a leading section, a vibration isolation section, a working section and a tail section. The working section is composed of a 32-element hydrophone. The hydrophone has the characteristics of high frequency bandwidth, high sound pressure sensitivity, low acceleration sensitivity and strong anti-interference ability.
(3) The eight-element array of flexural transducers uses the characteristics of strong mutual radiation effects of the first type of flexural transducers (lantern type) to obtain a high-performance 8 array test array to achieve low frequency (1.5). kHz), high power (15kW), wideband (1 octave) and high efficiency (>50%).
(4) In the theoretical research of the transducer array, the "directional comprehensive approximation method of directionality" is proposed, which has a breakthrough in theory. For example, using uniformly excited array elements, reasonable spacing, without amplitude beam control, the height of the side lobes can be suppressed to a height of only about 0105; using amplitude beam steering, using the "directivity comprehensive progressive approach" .The original traditional method has been improved so that it can balance the gain of the array, and the best unequal array can be obtained for all types of arrays, so that the array is narrower under the same sidelobe level and the same number of array elements. The main lobe and higher array sensitivity; using the "stepwise approximation" can also study super-directionality and use amplitude beam steering to rotate the beam.
Process of Transducer: