Modeling of acoustic liquid manipulation generated by a phased transducer array

Acoustic Liquid Manipulation is the use of the nonlinear effects of high powered, high frequency sound to move objects, manipulate fluid-fluid boundaries, create a fluid flow, and cause heating in a liquid. Experimental testing has shown that this technique has many applications in areas ranging from gas bubble control in fuel tanks for space vehicles to hyperthermia treatment of cancer. In order to produce easy control over a large range of volumes, many of these applications have made use of phased arrays which incorporate many transducers which run at a single frequency but whose amplitudes and/or phases can be independently controlled. Though substantial work has been done in experimentally verifying the capabilities of this technique, a comprehensive model of ALM needs to be developed to aid in the design of prototype apparatus as well as the proposal of future applications. The model equations utilized in this thesis include descriptions of the linear and nonlinear pressure and velocity fields as well as the excess pressure and radiation pressure that create forces on objects and surfaces, the acoustic streaming that causes the fluid to flow, and the heating effects. These equations were implemented using a MatLab code and were used to produce predictions for each of these quantities at each point in a grid of field points. A study of these results is also presented for various phased array parameters including transducer number and arrangement, inter-elemental spacing, array geometry, and transducer amplitude, phase, and frequency. The conclusions gathered from this study were found to be true for both the linear fields and most of the ALM effects and so it is possible to more effectively design transducer arrays for ALM applications using these trends