A Study of a Loudspeaker-driven and a Thermo-Acoustically-driven Travelling-wave Thermo-Acoustic Refrigerator

This paper describes the experimental investigation conducted on a Loudspeaker-Driven Thermo-Acoustic Refrigerator (LDTWTAR), a Standing Wave Thermo-Acoustic Engine (SWTAE) and a Thermo-Acoustically Driven Travelling Wave Thermo-Acoustic Refrigerator (TADTWTAR). This work aims at getting an insight into the coupling of a standing wave thermo-acoustic engine and a travelling wave thermo-acoustic refrigerator and to investigate its potential for cooling. Experiments were conducted in three stages. First, an analysis of LDTWTAR to analyze the effect of the geometric configuration on the temperature difference across the regenerator and to get an insight into the effect of the parameters of the system on its performance. Secondly, analysis of a SWTAE to investigate the relationship between the frequency of the engine and the length of the resonator. Lastly, both the SWTAE and the TWTAR were coupled together to form a TADTWTAR system. An experiment on the coupled system was conducted to get an insight into the coupling of a SWTAE and a TWTAR and analyse how the parameters of the SWTAE affect the cooling performance. The investigation of the SWTAE has shown that longer resonator lengths and lower power inputs yield lower frequencies, longer onset time and higher onset temperature of the engine. The investigation of the LDTWTAR has shown that different configurations of the refrigerator loop give different results indicating that the geometric configuration of the thermo-acoustic system affects its performance. Lastly, the investigation of the TDTWTAR showed a potential of the coupling even though the results reported were significantly hindered by the limitations inherent of the SWTAE considered, particularly the heat source.