Travelling wave thermoacoustic electricity generator for rural areas using a side-branch alternator arrangement

This paper illustrates the design, construction and testing of a looped-tube travelling wave thermoacoustic electricity generator that provides low-cost electrical power for remote and rural areas of developing countries. The system is designed numerically by using a specialized design tool DeltaEC, based on the linear thermoacoustic theory. A commercially available loudspeaker is connected via a 920 mm long side-branch tube to the 5.0 m long one wavelength looped-tube thermoacoustic engine. It is used to convert the acoustic power produced by the engine to useful electrical output. Air at atmospheric pressure is used as working gas to minimize the cost of the construction. The thermal power that drives the engine is supplied by a propane gas burner. It is shown that at an operating frequency of 64.5 Hz, the thermoacoustic generator can produce up to 13 W of electrical power. Results obtained from numerical analysis and experiments are presented and discussed in detail.