Focusing Modeling of OPFC Linear Array Transducer by Using Distributed Point Source Method

The improvement of ultrasonic phased array detection technology is a major concern of engineering community. Orthotropic piezoelectric fiber composite (OPFC) can be constructed to multielement linear array which may be applied conveniently to actuators and sensors. The phased array transducers can generate special directional strong actuator power and high sensitivity for its orthotropic performance. Focusing beam of the linear phased array transducer is obtained simply only by adjusting a parabolic time delay. In this work, the distributed point source method (DPSM) is used to model the ultrasonic field. DPSM is a newly developed mesh-free numerical technique that has been developed for solving a variety of engineering problems. This work gives the basic theory of this method and solves the problems from the application of new OPFC phased array transducer. Compared with traditional transducer, the interaction effect of two OPFC linear phased array transducers is also modeled in the same medium, which shows that the pressure beam produced by the new transducer is narrower or more collimated than that produced by the conventional transducer at different angles. DPSM can be used to analyze and optimally design the OPFC linear phased array transducer.

Download Full-text

Focusing Actuating Performance of OPFC Phased Array Transducer Based on DPSM

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.609-610.1299 ◽

2014 ◽

Vol 609-610 ◽

pp. 1299-1304

Author(s):

Zi Ping Wang ◽

Ying Luo

Keyword(s):

Phased Array ◽

Linear Array ◽

Fiber Composite ◽

High Sensitivity ◽

Ultrasonic Field ◽

Pressure Distributions ◽

Array Transducer ◽

Current Formulation ◽

Beam Directivity ◽

Mechanical Movement

As a new functional composite material, Orthotropic Piezoelectric Fiber Composite (OPFC) may be developed conveniently actuators and sensors. By constructing multi-element linear array, the phased array transducers can generate special directional strong actuator power and high sensitivity. The advantage of the transducers is that no mechanical movement is needed to scan an object. Focusing beam is obtained simply only by adjusting a parabolic time delay. The DPSM (distributed point source method) is used to model the ultrasonic field by OPFC linear array transducer. Using this approach, beam directivity and pressure distributions are studied to predict the behavior of focusing as compared to current formulation of traditional transducer. The interaction effect of two OPFC phased array transducers is also modeled in the same medium. Which shows the pressure beam produced by the OPFC array transducer is narrower or more collimated than that produced by the conventional transducer at different angles.

Download Full-text

Ultrasonic Field Modeling in Multilayered Fluid Structures Using the Distributed Point Source Method Technique

Journal of Applied Mechanics ◽

10.1115/1.2164516 ◽

2005 ◽

Vol 73 (4) ◽

pp. 598-609 ◽

Cited By ~ 23

Author(s):

Sourav Banerjee ◽

Tribikram Kundu ◽

Dominique Placko

Keyword(s):

Point Source ◽

Ultrasonic Field ◽

Ultrasonic Transducers ◽

Analytical Technique ◽

Source Method ◽

Fluid Systems ◽

First Case ◽

Fluid Layers ◽

Distributed Point Source Method ◽

Nonhomogeneous Fluids

In the field of nondestructive evaluation (NDE), the newly developed distributed point source method (DPSM) is gradually gaining popularity. DPSM is a semi-analytical technique used to calculate the ultrasonic field (pressure and velocity fields) generated by ultrasonic transducers. This technique is extended in this paper to model the ultrasonic field generated in multilayered nonhomogeneous fluid systems when the ultrasonic transducers are placed on both sides of the layered fluid structure. Two different cases have been analyzed. In the first case, three layers of nonhomogeneous fluids constitute the problem geometry; the higher density fluid is sandwiched between two identical fluid half-spaces. In the second case, four layers of nonhomogeneous fluids have been considered with the fluid density monotonically increasing from the bottom to the top layer. In both cases, analyses have been carried out for two different frequencies of excitation with various orientations of the transducers. As expected, the results show that the ultrasonic field is very sensitive to the fluid properties, the orientation of the fluid layers, and the frequency of excitation. The interaction effect between the transducers is also visible in the computed results. In the pictorial view of the resulting ultrasonic field, the interface between two fluid layers can easily be seen.

Download Full-text