Research On Very Low Frequency Sound Source

In this thesis, a round piston which inlays at infinite baffle plate is used for acoustic model. According to wave theory, the relations among the sound level, the working frequency and the dimension of the projectors are analyzed. The dimension of the spring is calculated for the transducer working at harmonic oscillation. In order to improve the rate of design and precision of the result, a software for the optimization of parameters of the transducer is compiled by means of MATLAB. The vibration of driver in transducers is simulated by ANSYS.In this design, two kinds of sealing technology are used to fulfill the requirement that the very low frequency projector can be worked at a large volume displacement. To equalize the pressure of water, a pressure compensation system is designed in the transducer.Two types of very low frequency projectors are manufactured. One was sealed with a vibrator in it. The other is designed by using of electromagnet. Finally, an electro-acoustic performance test has been done in water pool and Song Hua Lake to verify the feasibility of the design.