Demonstration on the nonlinear scattering of crossed ultrasonic beams in presence of single bubble in water

An apparatus consisting of an open thin-wall clear acrylic rectangular tank is used to resonate the volume cavity of water in an nx=1, ny=1, nz=3 mode; such that a mm sized bubble or less can be levitated in the center of the tank. The authors will utilize the experimental arrangement suggested by T.J. Asaki, P.L. Marston, and E.H. Trinh [“Shape oscillations of bubbles in water driven by modulated ultrasonic radiation pressure: Observations and detection with scattered laser light,” JASA 93, p 706-713, (1993)]. In which, their experimental apparatus involves a description of their piezoelectric driver, which couples into the bottom of the tank. Next, the demonstration consists of the nonlinear scattering of crossed ultrasonic beams of primary frequency components: f1=1.9 MHz, f2= 2.1 MHz; which, interact nonlinearly with the bubble to produce nonlinear scattering outside the interaction region at the combination frequency f+ = 4.0 MHz. The receiving 4 MHz transducer unit will measure the nonlinear scatter...