Haifeng Zhang, PhDMechanical and Energy Engineering, University of North Texas
A piezoelectric resonant sensor is a device that usually contains a quartz crystal element vibrating at resonance, which changes its output frequency, as a function of physical parameters such as pressure, temperature, mass, and electric field. Since frequency can be measured with far higher accuracy than any other quantity, this type of sensors have advantages of their unsurpassed high stability and high resolution. This type of sensors have been used in accurate monitoring of pressure and temperature in several modern industrial segments such as the automotive, aerospace, gas turbine, nuclear power, and gas and oil exploration. However, harsh environmental conditions, including extremes of pressure, temperature, vibration, shock, radiation, etc., pose a great challenge for conventional piezoelectric resonant sensing devices as most existing sensing elements could not survive in such harsh environments.
This talk will focus on the speaker’s recent work on novel piezoelectric resonant sensors based on high-temperature piezoelectric crystal-Langasite (La3Ga5SiO14). Several key issues on the design of langasite-based BAW (Bulk Acoustic Wave) and SAW (Surface Acoustic Wave) resonant pressure/temperature sensors will be discussed. The discussion includes the design principle and theoretical analysis for a novel dual-mode pressure/temperature sensor, fabrication and experiment measurements for langasite pressure sensors and other type of sensors.
In addition, piezoelectric energy harvesting provides a promising way to collect waste energy and use it to power micro sensors and other devices, thus this talk will cover the speaker’s recent work on theoretical analysis and experiment for a novel broadband piezoelectric vibration energy harvester. Furthermore, this talk will present the speaker’s relevant work on structure health monitoring and ultrasonic nondestructive evaluation.
Dr. Zhang is an Associate Professor of the Department of Mechanical and Energy Engineering at the University of North Texas (Denton, TX). His research interests include advanced sensors, energy harvesters, structural health monitoring and ultrasonic nondestructive evaluation. Dr. Zhang has been the PI or a co-PI of $4.7M grants (his own share $2.0 M) from a variety of federal funding agencies (NSF, ARO, DoD, DOE, USDA, US Army) and industry. At present, he is the PI/Co-PI of 8 funded projects from NSF, DOE, USDA, US Army, Peterbuit Motor Company and UNT. He has published more than 45 journal and conference papers. He received his B.S. in Engineering Mechanics from Hunan University, China in 1997, his M.S. degree in Solid Mechanics from Northwestern Polytechnical University, Xian, China, in 2001, and his Ph.D. degree in Engineering Mechanics from University of Nebraska, Lincoln in 2007. He was a postdoctoral researcher in the Department of Material Science and Engineering in the Ohio State University before joining in University of North Texas in 2008. Dr. Zhang is the committee member of ASME energy harvesting technical committee.
Host: Dr. Michael Scott