ELECTROMECHANICAL FINITE ELEMENT MODELS FOR ULTRASOUND TRANSDUCER ANALYSIS AND DESIGN

ULTRASOUND WORKS BY ILLUMINATING THE BODY'S INTERIOR WITH SHORT, HIGH FREQUENCY SOUND BURSTS, PROCESSING THE ECHOES NUMERICALLY, AND DISPLAYING THE MOVING IMAGE IN REAL-TIME ONA CRT SCREEN. ITS UTILITY AND RANGE OF APPLICATION INCREASESUBSTANTIALLY EACH YEAR DUE TO INNOVATIVE NEW EQUIPMENT AND PROCEDURES. THE HEART OF ULTRASOUND IS THE TRANSDUCER. OF COURSE, IMAGE PROCESSING AND DISPLAY ARE IMPORTANT, BUT THEYARE ULTIMATELY DEPENDENT ON A STRONG TRANSDUCER SIGNAL. ALTHOUGH ENHANCEMENTS ARE CONTINUALLY ADDED TO TRANSDUCER DESIGNS, THERE ARE LIMITS IMPLICIT IN THE CUSTOMARY EXPERIMENTAL DESIGN CYCLE. MANUFACTURERS SEE COMPUTER SIMULATION AS THE WAY TO ESCAPE THIS CYCLE AND EXTEND THE DESIGN LIMITS. A COMPREHENSIVE NUMERICAL SIMULATION CODE IS URGENTLY NEEDEDTO OVERCOME THE LIMITATIONS OF CURRENT TRANSDUCER MODELS ANDHELP PROMOTE MORE EFFICIENT DESIGN METHODOLOGIES. WE PROPOSE TO DEVELOP AND SELL SUCH A CODE TO THE ULTRASOUND COMMUNITY. THE CODE WILL PERMIT COMPLETE, THREE-DIMENSIONAL, TIME-DOMAIN FINITE ELEMENT MODELING OF TRANSIENT WAVES IN PIEZOELECTRIC-ELASTIC-ACOUSTIC MEDIA. ANEXISTING ELASTIC FINITE ELEMENT PROGRAM DEVELOPED BY WEIDLINGER ASSOCIATES SUPPLIES THE FRAMEWORK. THE PROJECT WILL PROVIDE AN ADVANCED LEVEL OF SIMULATION BY TAKING ADVANTAGE OF MODERN ALGORITHMS ALONG WITH THE POWERFUL WORKSTATIONS AND CAD RESOURCES AVAILABLE TODAY. IT IS EXPECTED THAT THIS WORK CAN ESTABLISH A U.S. MODELING CAPABILITY WITH SIGNIFICANT ADVANTAGES OVER PROGRAMS REPORTED IN EUROPE AND JAPAN, AND HELP DOMESTIC COMPANIES RETAIN LEADERSHIP OF THE ULTRASOUND BUSINESS THROUGH THE 1990S.