Research On Experiment Methods Of Reducing Amplitude Of Linear Spectrum With Reciprocating Machinery Features

Submarine noise in high, medium frequency has been solved successfully, but there is nobreakthrough for low frequency isolation and linear spectrum suppression. In addition, theimprovement of submarine sound stealth performance was restrained because of linearspectrum stimulation in low frequency spectrum which was not easy attenuation, energyconcentration, absorbed hardly by external medium. For the reasons, this paper studied aexperimental device that reduce low frequency vibration amplitude, also restrain its linearspectrum, and established the corresponding simulation model, verify experimental results.The main research contents are as follows:Firstly, according to two degrees of freedom vibration model, the paper solveddisplacement amplitude, determined mass ratio, damping, linear stiffness parameters of tunedvibration reduction device, selected preliminary parameters for making the equipment device.Secondly, the paper detailedly introduced main components of four vibration isolationmethod: the air spring of double isolation, the cantilever beam and masses of passive tunedvibration reduction, the actuator and controller of active control device, the ball-spring andneedle-hanging of disturbance device, while determined the size and the related parameters ofeach element to prepare for the installation and debugging of experimental device.Thirdly, the paper described the working principle of vibration isolation device,established the theory of vibration isolator model, and made stress analysis, then obtainedrelated vibration equation, supplied further guidance for installation and debugging of experiment device, then gradually started measurement and got experimental effect of deviceof double-layer isolation, double-layer isolation+passive tuned vibration reduction,double-layer isolation+passive tuned vibration reduction+active control and doubleisolation+passive tuned vibration reduction+disturbance.Finally, according to experimental device specific parameters, we established experimentmodel and vibration equations, built corresponding entities physical model with ANSYS, thenmade numerical simulation as experimental corresponding order and verified experimentalresults.This experiment device effectively reduced the linear spectrum amplitude in lowfrequency, but also increase background noise, reduced output SNR, reached the desiredexperimental effect.