阵元失效对超声阵列换能器的影响及优化研究

摘要

超声阵列换能器单个或多个阵元的振动效率、几何尺寸等参数的改变,会影响整个阵列的声场分布等性能参数,降低超声检测的分辨率及相应的检测效果.基于阵列换能器声压分布理论,利用自适应算法,从阵元激励的角度,探讨阵列超声换能器阵元激励的优化方法,消除阵元失效的影响.研究结果表明,利用声场分布空间中有限数量的优化参考点,经过对激励参数的优化,可以使有阵元失效阵列的整个声场分布、指向性及聚焦特性等性能指标与标准无阵元失效阵列的基本一致,达到期望的标准声场分布的参数指标,大大降低超声检测设备的应用成本,提高检测效果.%Array transducer is the crucial component of all kinds of these instruments depending on ultrasonic phased array technology.While,efficiency changing and size error of a single element or several elements can make significant negative effects on the acoustic field and its directivity,and reduce the detection effect on the field of high performance and high resolution application.Using the adaptive algorithms,we presented a method to optimize and correct the array from the excitation mode of elements.By adjusting the excitation amplitude of each normal elements,the influence to the acoustic field from element failure can be decreased availably.The experiment results and theoretical analysis indicate that this method is much available to correct the acoustic field of the array with disabled elements by using the acoustic pressure of a few reference points in the field.In consequence,the array transducer with element failure or size errors can be well optimized by the method we proposed.