The Study Of The Acoustic Field Produced By Small Size Phased-array Transducer

In the paper,the normal and phased arc array sources are represented.The numerical simulation with two-dimension finite difference equations methods are used for studying acoustic field in a slim borehole.The acoustic field are different,which is excited by monopole,dipole,quadrupole,three and five phased arc array sources.The physical simulation excited by slim hole phased arc array is accomplished in the acoustic logging laboratory of China University of Petroleum,Beijing.By loading different sources in the phased array,the experimental data in multipole model and phased array model of acoustic field have been obtained respectively.The results show that directivity formula of monopole radiated acoustic field is nearly a status of circle,while the dipole is approximate equal to”?”,which reveals that the different delay incentives of phased array source can control the deflection of acoustic beam direction.Combined with numerical and physical simulation experiment data of acoustic field,numerical simulation and physical experiment of slim hole multipole source model of acoustic directivity are basically identical.Compared two methods,numerical simulation and physical experiment with slim hole phased acoustic logging acoustic field produced by the transducer,the difference of the directivity is analyzed.In summary,the overall level of slim hole phased array source within 3dB wide angle is small.It has a good directive character and achieves the desired results.All the data contribute a lot to the studying of slim hole phased acoustic logging equipment,especially its future development.