Research On Active Vibration Control Of Piping System By Using Inertial Actuator

Vibration of piping system on submarines is undesirable as it may induce noise andtransmit it to the sea, as well as promotes fatigue, even cause damage to pipe. What’s worse,connection part of pipes may break. So, it is a danger to submarines, as well as sailor’s safe.To suppress piping system’s vibration effectively, this paper focus on suppress piping system’svibration by using inertial actuator.Firstly, this paper presented and concluded research and development status of activevibration and noise control technique of which being applied to ships and piping systemcurrently, mentioned characteristics and development status of active vibration absorptiontechnology, introduced the research orientation and main work.Conveyed vibration measurement experiment on submarine, concluded that vibration ofsubmarine is mainly consist of discrete spectrum. Proposed active vibration control system ofpiping system, inertial actuator was chosen as actuator in this system. Modeling dynamicmodels of acceleration, velocity and displacement feedback control, got the relationship offeedback ratio with control effect by simulation, simulation result revealed that velocityfeedback control can achieve the best control effect in the three feedback control methods. Toimprove control effect of low frequency linear spectrum and real-time control, proposedadaptive control algorithm based on online frequency discern.Presented the function and parameter of inertial actuator; got the dynamic characteristicof it by experiment; improve the performance of inertial actuator by adding code of digitalnotch filter to the program in digital signal processing system, frequency span enlarged aftercompensation. Designed a pedestal for the inertial actuator to installed on the pipe system,doing finite element analysis to the pedestal by using ANSYS, simulation results proved thatits model frequencies are above the working frequency of control system, it can applied to thecontrol system effectively.Designed and write programs of integration algorithm of acceleration signal and adaptivecontrol algorithm of which based on on-line frequency discern for a digital signal processingsystem. After test integration algorithm of acceleration signal by doing simulation and experiment, it turns out that this algorithm can remove trend term effectively. Test the adaptivecontrol algorithm of which based on on-line frequency discern by doing simulation, simulationresult proves that the control algorithm can suppress discrete spectrum effectively.Lastly, conduct experiments on a closed piping system, excited source is shaker andpump respectively. Acceleration signal was measured on control point and foundation beforeand after active control turns on. In the experiment of which select shaker as excited source,acceleration feedback control, velocity feedback control and adaptive control based on onlinefrequency discern was applied. After compared those data of which being measured, itrevealed that adaptive control based on online frequency discern achieved the best controleffect. In the following experiment, pump was turned on. The velocity of pump turned to2500to2900rpm. Experiment result shows that vibration of pump’s shaft frequency and its secondorder harmonic frequency can decrease6dB on control point; vibration of pump’s shaftfrequency and its second order harmonic frequency can decrease3dB on pedestal.