Power Ultrasonic Device Design

WORKSHOP I Basic Principles of Piezoelectric Materials

Objectives: 

To introduce basic principles of ferroelectric materials.

To understand mathematical definitions of piezoelectric characteristics.

To learn the influences of various external factors (temperature, electric field, frequency…) on the materials performance.

To learn how to read datasheet of commercial piezoelectric materials.

To recognize the techniques for measuring and validating the performance of piezoelectric components.

Syllabus:

· Piezoelectric Effect

· Dielectric, Piezoelectric, Pyroelectric, Ferroelectric

· Electric Dipoles

· Domains and Domain Wall

· Polarization Mechanisms

· Dielectric Constant

· Dielectric Loss

· Field Tensors

· Ferro- Pyro-Piezo

· Polarization vs Electric Field

· Piezoelectric Constants

· Piezoelectric Voltage Coefficient 

· Electromechanical Coupling Coefficient

· Mechanical Quality Factor

· Strain-Charge\Stress-Charge Form

· Complete Set of Piezoelectric Material Coefficients

· Mode of Deformation

· Frequency Constant

· Soft VS. Hard Ceramics

· PZT Rings

· Phase Diagram

· Curie Temperature

· Thermal Stability

· Quasi-static d33

WORKSHOP II Basic Principles of Piezoelectric Materials

Objectives: 

To understand wave propagation in solid materials.

To understand governing equations in describing a vibrator. 

To explore solutions to the governing equations to resolve the resonant frequency and displacement distribution.

To learn to use Mathcad software to solve governing equations and find the solutions.

Syllabus:

· Velocity of Sound in Solids

· Simple Spring — Mass Oscillator

· Real Condition — Damped Simple Harmonic Motion

· Effect of Damping on Phase Relationships — The Forced Oscillator

· General Wave Equation

WORKSHOP III Experiment

Objectives: 

To Characterizations of Piezoelectric Materials (Ceramics, Polymer with different dimensions)

Syllabus: 

· Quasi-static d33, d31, d15 test

· Operation of Impedance analyzer instrument

· Operation of LCR meter

· Test of impedance spectrum to determine harmonic vibration

· Equivalent circuit analysis of resonator impedance spectrum

· Calculation of mechanical quality factors

· Static capacitance test and dielectric constant calculation

· Piezoelectric voltage coefficient g31 and g33 calculation

· Frequency constant Nd, N1, N2, N3, Nt test and calculation

· Coupling factor kp, k31, k33, k15, kt calculation

· Speed of sound measurement for ceramic, alloy, and polymer

· Acoustic impedance test

· Compliance s11E, s33E s55D measurement

WORKSHOP VI Design of Single Horn

Objectives: 

To understand the design of various typical horns.

Syllabus: 

· Horn Equations

· Cylinder or Uniform Bar as an Ultrasonic Horn

· Stepped Horn (Double Cylinder)

· Exponentially Tapered Horn

· Wedge-Shaped Horn

· Conical Horn

· Catenoidal Horn

WORKSHOP V Design of Practical Horn

Objectives: 

To learn horn with two segments and evaluate the performance.

To introduce the functionality of components of horn design.

To understand the selection criteria of horn components.

To learn the critical considerations in designing a horn for practical applications.

Syllabus: 

· Stack Converters

· Converter Booster

· Converter Booster Horn

· T-network Circuit / Impedance

· Front Driver

· Back Driver

· Electrode

· Stack Bolt: Low Axial Stiffness

· Low Axial Stiffness

· Stack Bolt Selection

· Insulation

· Assembly

· Ageing

WORKSHOP VI Experiment

Objectives: 

To evaluate of Performance Evaluation of Horns

Syllabus: 

· Test of impedance spectrum

· Evaluate the mechanical quality factor

· Study the influence of temperature to the operation frequency range

· Test the load influence on the operation condition

WORKSHOP VII Software Simulation

Objectives: 

To introduce the basic knowledge of finite elements analysis

To learn COMSOL modeling.

To learn COMSOL simulation and results analysis.

Syllabus:

· COMSOL Acoustic Module

· COMSOL Piezoelectric Horn Design

· COMSOL Coupling Matrix Input

· COMSOL Simulation

· COMSOL Data Analysis