EXPERIMENTAL STUDY OF A TRANSCRITICAL THERMOACOUSTIC ENGINE WITH POWER EXTRACTION APPLICATIONS

An experimental study was performed on a low frequency transcritical thermoacoustic engine developed at Maurice J. Zucrow Laboratories. The goal of the experiment was to characterize the effects of engine geometry on the thermoacoustic production of the working fluid and to use insights gained to design a power extraction device for the transcritical thermoacoustic engine. The effects of geometry were investigated by parametrically varying the length of the resonator and the diameter of the resonator and measuring the pressure amplitude and frequency of thermoacoustic instabilities developed at varying ∆T and one bulk pressure of P Pcr = 1.1. It was found that increasing resonator length increases pres?sure amplitude, decreases frequency, and increases acoustic power developed. Increasing resonator diameter decreases pressure amplitude, increases frequency, and increases acoustic power developed. It was also experimentally proven that coiled tube sections in the res?onator attenuate the thermoacoustic pressure wave. After testing, the knowledge gained was applied to the design of a bidirectional impulse turbine for eventual integration into a scaled-up version of the current thermoacoustic engine to be used to extract power from the thermoacoustic instabilities developed in the rig.