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A new high-saturation induction, high-temperature nanocomposite alloy for high-power inductors is discussed. This material has FeCo with an A2 or B2 structure embedded in an amorphous matrix. An alloy of composition Fe56Co24Nb4B13Si2Cu1 was cast into a 1.10in. wide, 0.001in. thick ribbon from which a toroidal core of approximately 4.25in. outer diameter, 1.38in. inner diameter, and 1.10in. tall was wound. The core was given a 2T transverse magnetic field anneal, and impregnated for strength. Field annealing resulted in a linear B-H response with a relative permeability of 1400 that remained constant up to field strengths of 1.2T. The core was used to construct a 25μH inductor for a 25kW dc-dc converter. The inductor was rated for operation in discontinuous conduction mode at a peak current of 300A and a switching frequency of up to 20kHz. Compared to commercially available materials, this new alloy can operate at higher flux densities and higher temperatures, thus reducing the overall size of the inductor.

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Bi-directional turbines convert oscillating axial fluid flow into uniform radial rotation and have proven effective in wave energy harvesting applications, like ocean wave generators. Two of the most widely studied designs for these scenarios are the Wells and axial turbines. This study characterizes the effectiveness of these turbines for use with a thermoacoustic generator; which is a relatively new technology that uses an induced temperature gradient to propagate acoustic waves within an enclosed, looped chamber. These generators are widely applied to refrigeration cycle systems; yet when paired with a bi-directional turbine, the resulting sound wave can be harnessed to generate electricity. This paper begins with a discussion of the thermoacoustic application covering relevant issues for the turbine. Next, the Wells, axial, and a combined hybrid turbine are presented in thorough detail including governing design features that were explored. Fabrication of a test fixture and turbine prototypes and experimental results from a broad ranging study of the performance of the turbine designs is shown. Finally, conclusions from the obtained results are discussed.