Design of ultrasonic array elements for acoustic power considerations

Area of Science:

• Engineering
• Acoustics
• Materials Science

Background:

• Acoustic power is crucial for therapeutic ultrasound transducer/array design.
• Current design strategies may not be optimal for array elements.

Purpose of the Study:

• Develop a methodology to enhance acoustic power radiated from fluid-loaded piezoelectric array elements at a fixed frequency.
• Optimize piezoelectric element thickness and matching layer thickness.

Main Methods:

• Integrate a gradient-based optimization algorithm within a finite element framework.
• Employ a method to avoid explicit remeshing during optimization iterations.
• Validate numerical results with experimental measurements.

Main Results:

• Optimized designs for piezoelectric array elements were determined numerically.
• The developed design methodology effectively enhances acoustic power output.
• Experimental measurements confirmed the effectiveness of the proposed design method.

Conclusions:

• The proposed gradient-based optimization within a finite element framework enhances acoustic power.
• Conventional 1D transducer analysis and rule-of-thumb sizing are suboptimal for array elements in acoustic power applications.
• This validated method provides superior designs for fluid-loaded piezoelectric arrays.