US Patent 9457302 Acoustophoretic device with piezoelectric transducer array

An apparatus for separating particles from a fluid stream includes a flow chamber that has at least one inlet and at least one outlet. At least one ultrasonic transducer is located on a wall of the flow chamber. The transducer includes a piezoelectric array with at least two piezoelectric elements. The piezoelectric array includes a piezoelectric material to create a multi-dimensional acoustic standing wave in the flow chamber. A reflector is located on the wall on the opposite side of the flow chamber from the at least one ultrasonic transducer.