相控环形阵辐射声场特性分析  

The Characterization of the Radiation Acoustical Fields of an Annular Phased Array

作　　者：段文星[1,2] 乔文孝[1,2] 车小花 

机构地区：[1]中国石油大学油气资源与探测国家重点实验室,北京102249 [2]北京市地球探测与信息技术重点实验室,北京102249

出　　处：《测井技术》2013年第2期143-148,共6页Well Logging Technology

基　　金：国家自然科学基金项目(批准号:61102102;11134011);国家重大科技专项(课题编号:2011ZX05020-009);中国石油天然气集团公司项目(课题编号:2011A-3903)资助

摘　　要：传统的井下超声电视等井下超声测量技术中往往采用圆形活塞辐射器,其焦距和指向性固定,对于不同内径和厚度的套管井适应能力不好。理论模拟相控环形阵辐射器辐射声场的分布,分析相控环形阵辐射器各个参数对辐射声场的焦距和指向性的影响。相控环形阵辐射器阵元尺度的选择采用等面积方案有利于辐射面积在相控环形阵面内的均匀分布;使用相控阵时采用高频更利于辐射能量沿轴线集中辐射;相对于圆形活塞辐射器,相控环形阵辐射器可以在较低的频率下获得较小的焦斑直径,通过调整相位延迟获得不同的焦区范围,适应不同内径套管的超声成像测井要求。Traditional down hole ultrasonovision and some down hole ultrasonic measurement techniques often use circular piston radiator, its focal length and direction are fixed, so it has the poor adaptability to different diameters and thicknesses of the cased holes. We simulate the radiation acoustical fields of the annular phased array in theory, and analyse the effects of the parameters of the annular phased array and the radiation acoustical fields on the focal length and direction. The above results show,The array element in the array is designed as iso-area so that the radiation area of the array may be uniform distribution; The higher frequency in the array makes the radiation energy radiation along the axis line; Relative to the circular piston radiators, the annular phased array can achieve dynamic focusing by adjusting excitation signal phase of each unit, and it can be applied to the requirements of cased hole ultrasound imaging with different internal diametes.

关 键 词：测井方法 相控环形阵 动态聚焦 焦斑 超声成像测井 

分 类 号：P631.811[天文地球—地质矿产勘探]