Ahmad Rais, Kundu Tribikram, Placko Dominique
Department of Civil Engineering and Engineering Mechanics, University of Arizona, Tucson, Arizona 85721, USA.
J Acoust Soc Am. 2005 Apr;117(4 Pt 1):1762-76. doi: 10.1121/1.1835506.
Phased array transducers are multi-element transducers, where different elements are activated with different time delays. The advantage of these transducers is that no mechanical movement of the transducer is needed to scan an object. Focusing and beam steering is obtained simply by adjusting the time delay. In this paper the DPSM (distributed point source method) is used to model the ultrasonic field generated by a phased array transducer and to study the interaction effect when two phased array transducers are placed in a homogeneous fluid. Earlier investigations modeled the acoustic field for conventional transducers where all transducer points are excited simultaneously. In this research, combining the concepts of delayed firing and the DPSM, the phased array transducers are modeled semi-analytically. In addition to the single transducer modeling the ultrasonic fields from two phased array transducers placed face to face in a fluid medium is also modeled to study the interaction effect. The importance of considering the interaction effect in multiple transducer modeling is discussed, pointing out that neighboring transducers not only act as ultrasonic wave generators but also as scatterers.
相控阵换能器是多阵元换能器，其中不同阵元以不同的时间延迟被激活。这些换能器的优点是扫描物体时无需换能器进行机械运动。聚焦和波束控制只需通过调整时间延迟即可实现。本文采用分布式点源法（DPSM）对相控阵换能器产生的超声场进行建模，并研究两个相控阵换能器置于均匀流体中时的相互作用效应。早期研究对传统换能器的声场进行了建模，在传统换能器中所有换能器点同时被激发。在本研究中，结合延迟激发的概念和分布式点源法，对相控阵换能器进行半解析建模。除了对单个换能器进行建模外，还对置于流体介质中面对面的两个相控阵换能器的超声场进行建模，以研究相互作用效应。讨论了在多换能器建模中考虑相互作用效应的重要性，指出相邻换能器不仅充当超声波发生器，还充当散射体。
