Comparison of a 31 and 33 mode PZT cylinder in a broadband unlimited - - PowerPoint PPT Presentation

UDT 2020 Session : Pro-Active Sonar: What's Happening in the World of Transducer Design & Characterisation ? Subject : Innovations and utilizations of piezoelectric ceramics in ocean acoustic sensors and transducers

Comparison of a 31 and 33 mode PZT cylinder in a broadband unlimited depth transducer

Send-Receive Transducer Applications

– Underwater communications – Beacons – Range Tracking – Acoustic Triggers

Introduction

Send-Receive Transducer Requirements

– Low Frequency Broadband (8-14kHz) – High Pressure – Hemispherical Beam

Introduction

PZT material selection Conceptual Design FEM Modelling Assembly

Approach

Approach

PZT material selection

Navy Type I (BM402) Navy Type III (BM800) Relative dielectric consant 1350 1000 Dissipation factor (%) 0.4 0.3 d33 (10-12 C/N) 305 225 k33 0.71 0.64 kp 0.60 0.5

Approach

Conceptual Design

• High (Unlimited) Depth Options

Free Flooded Ring – toroidal beam pattern Oil-Filled

Approach

Conceptual Design PZT ceramic in 31 mode (classic inside/outside electrodes) PZT ceramic in 33 mode (striped electrodes),

• ffering higher K and g33

Approach

Conceptual Design

• High (Unlimited) Depth Options

Oil filled transducer– hemispherical beam pattern

Approach

FEM Modelling

Approach

FEM Modelling

Approach

Assembly of Transducers a)Free Flooded Ring, 31 mode cylinder b) Oil Filled Transducer, 31 mode cylinder c) Oil Filled Transducer, 33 mode cylinder

Approach

Results

Results

Results

Beam Pattern XY Radial Plane

Results

Beam Pattern XZ Axial Plane

• Sea Trials
• Turning the aspect ratio of the cylinders, to

further couple the 8kHz Helmholtz resonance with the 13kHz radial resonance

• Scaling the design, using same principle design

for lower or higher frequencies

Future Work