TY - JOUR ID - 246039 TI - Investigation and Comparison of Three Popular Ultrasonic Generators (PZT, PVDFEMFi) for Employing in Acoustic Scaling JO - Iranian Journal of Mechanical Engineering Transactions of the ISME JA - JMEE LA - en SN - 1605-9727 AU - Saffar, S. AD - Corresponding Author, Associate Professor, Department of Acoustics and Sound Engineering, IRIB University, P.O. Box 1986916511, Tehran, I.R. Iran Y1 - 2021 PY - 2021 VL - 22 IS - 2 SP - 21 EP - 37 KW - acoustic impedance KW - matching layers KW - Ultrasonic transducers KW - Genetic algorithm (GA) KW - PZT KW - PVDF KW - EMFi DO - 10.30506/jmee.2021.128422.1231 N2 - Acoustic scaling is one of the efficient techniques for measuring acousticparameters of large and luxury places. Due to the range of acousticscaling frequency, an airborne ultrasonic transducer has been used fortransporting the power to the air. One major problem of ultrasonictransducers, radiating acoustic energy into the air, is to find the properacoustic impedance of one or more matching layers. This work aims atdeveloping an original solution to the acoustic impedance mismatchbetween transducer and air. Therefore we consider three piezoelectrics,PZT, PVDF, and EMFi transducers and air that have high acousticimpedance deference. We proposed the use of a genetic algorithm (GA) toselect the best acoustic impedances for matching layers from the materialdatabase for a narrow band ultrasonic transducer that works at afrequency below the 1MHz by considering attenuation. This yields ahighly more efficient transmission coefficient. Also, the results showedthat by using the increasing number of layers we can increase our chanceto find the best sets of materials with valuable both in acoustic impedanceand low attenuation. Precisely, the transmission coefficient is almosthigher than 80% for the more studied cases. UR - https://jmee.isme.ir/article_246039.html L1 - https://jmee.isme.ir/article_246039_f12dd0470bf803968e984f8f14896ded.pdf ER -