Pressure amplification mechanism for airborne ultrasound: Air-DPLUS

Airborne ultrasound is a promising technology in food and agriculture industries. However, its practical application is limited by its high energy attenuation and short propagating distance. In this work, we introduced a new system called Air-DPLUS (airborne double-parabolic-reflector wave-guided ultrasonic transducer), consisting of a focusing mechanism combined with a cylindrical airborne transducer. We evaluated the output pressure and its axial distribution in simulations and experiments. Under transient and continuous excitation, our prototype Air-DPLUS amplified the maximum pressure 6.9 and 24.4 fold, respectively, in comparison with the use of an airborne transducer alone.