Application of ferrofluids as an acoustic transducer material

Application of ferrofluids to electroacoustic transduction is discussed. A design of a piston-type transducer is described, and power transfer calculations are given, showing that useful levels of acoustic power emission can be obtained at intermediate frequencies (100 to 3000 Hz). A toroidal configuration is proposed as an alternative that essentially utilizes the fluid properties of the material and that, in principle, can be employed in large dimensions for very low frequencies.