Research Papers

Suspension Design, Modeling, and Testing of a Thermo-Acoustic-Driven Linear Alternator

[+] Author and Article Information
C. R. Saha, R. Jinks

School of CEM Coventry University,
Coventry CV1 5FB, UK

Paul. H. Riley

Department of Mechanical Engineering
and Aeronautics,
City University of London,
London EC1V 0HB, UK

C. M. Johnson

School of Electrical & Electronic Engineering,
Nottingham University,
Nottingham NG7 2RD, UK

Contributed by the Technical Committee on Vibration and Sound of ASME for publication in the JOURNAL OF VIBRATION AND ACOUSTICS. Manuscript received February 13, 2017; final manuscript received October 7, 2017; published online November 10, 2017. Assoc. Editor: Alper Erturk.

J. Vib. Acoust 140(2), 021014 (Nov 10, 2017) (5 pages) Paper No: VIB-17-1059; doi: 10.1115/1.4038270 History: Received February 13, 2017; Revised October 07, 2017

The Score-Stove™ generates electricity from a wood-burning cooking stove using a thermo-acoustic engine (TAE) that converts heat to sound through a linear alternator (LA). This paper introduces a prototype hemitoroidal suspension that was refined into a segmented trapezoidal shape that gave a higher cyclic life for the LA and includes a critical evaluation that compares a theoretical analysis with experimental results. The results show an improvement from the 40% efficiency of a standard loudspeaker used in reverse as an LA to 70–80% efficiency with the new suspension and a double Halbach array magnetic topology.

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The University of Nottingham, 2017, “ The Score Project,” The University of Nottingham, Nottingham, UK, accessed Oct. 31, 2017, www.score.uk.com
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Grahic Jump Location
Fig. 1

Hemitoroidal shape alternator (a) without slot and (b) with slot

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Fig. 2

Hemitoroidal shape alternator

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Fig. 3

Displacement curve

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Fig. 4

Free air quality factor of the alternator with and without blocking slot

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Fig. 5

Segmented trapezoidal shape suspension

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Fig. 6

Semicircular cantilever analysis

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Fig. 7

Double leaf trapezoidal shape semicircular cantilever

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Fig. 8

Measured displacement for different mass using dial gauge




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