Research On Acoustic Emission Monitoring System Based On LabVIEW

With the rapid development of industry,all kinds of mechanical equipment are widely used.Most of the working environment of mechanical equipment is in a corrosive industrial environment,so the production safety of the equipment should not be underestimated.In order to ensure the safety of production,it is necessary to use the way of acoustic emission detection on-line monitoring to carry out the maintenance inspection of mechanical equipment.Acoustic emission is a kind of physical phenomenon that can produce transient elastic wave when its structure changes.Acoustic emission technology can realize on-line monitoring by detecting the change of acoustic emission signal of mechanical equipment,so as to avoid greater loss of equipment caused by shutdown.Therefore,the acoustic emission monitoring technology is used for nondestructive testing of mechanical equipment,and a set of acoustic emission monitoring system is designed with LabVIEW as the development environment.Based on PCI-2 acquisition card of American physical acoustics company and LabVIEW development environment,this thesis completed the design of acoustic emission monitoring system.The whole system includes two aspects: hardware system and software system.The hardware system introduces the components of hardware equipment and the model selection of using devices in detail.Due to the high real-time requirements of acoustic emission monitoring system,for meet the requirement,first of all,according to the system development environment and communication mode,basing to the modular design idea,develop the system design scheme,and realized the acquisition,display,storage,playback and analysis functions of acoustic emission signals.Secondly,through the understanding of acoustic emission technology and the study of acoustic emission signal processing method,the noise source and noise reduction method of acoustic emission signal were understood.The collected acoustic emission signal was denoised by wavelet method,and the generation of defects was identified and judged by the method of envelope spectrum analysis.At last,the real-time monitoring system of acoustic emission signal was tested.In the process of experiment,each sub module was debugged many times to optimize its performance.The experimental results show that the whole system can run smoothly,thefunction of each sub module is perfect,the generation of acoustic emission signals can be monitored in real time,the collected acoustic emission signals can be processed and analyzed,and the defects can be identified effectively.