Performance alteration of standing-wave thermoacoustically-driven engine through resonator length adjustment

Abstract: The production of sound-wave in thermo-acoustic device is necessary to induce cooling or generate electricity. The magnitude of the sound-wave is normally proportional to the amount of heat provided to the device. The possibility to use waste heat in any locations can be enough to justify the use of thermo-acoustic technology for sustainable electricity generation or refrigeration. In this work, an adjustable thermoacoustically-driven engine has been developed using the Design Environment for Low-amplitude ThermoAcoustic Energy Conversion (DELTAEC). Many studies have highlighted the relationship between the geometry of the stack and the performance of the device. Unlike previous studies, the resonator of this thermoacoustically-driven device, made of two portions, was adjusted. The performance of the device has been analysed in order to evaluate the influence of the alteration of the resonator on the heat-to-sound conversion. Performance indicators like the acoustic power, the temperature difference across the stack and the frequency of the sound-wave have been studied. This work point out the possibility to regulate the performance of thermo-acoustic engine by adjusting the geometry of the resonator

Performance evaluation of ceramic substrates for cooling applications in thermo-acoustic refrigerators

Abstract: Thermo-acoustic refrigerators have recently drawn more attentions because of its eco-friendlier potential to address the current environmental issues resulting from the use of traditional vapour compression refrigerators. This paper aims at evaluating different selected ceramic substrates, with square pores, from the point of view of their performance as stack materials in the design of thermo-acoustic standing wave refrigerators. A 465 mm standing wave thermo-acoustic refrigerator was designed using numerical approximation provided by a modeling code called DELTAEC (Design Environment for Low-amplitude ThermoAcoustic Energy Conversion). The design developed focuses, in particular, on the effects of different ceramic substrate configurations (diameter, length, porosity and position) on the performance of the device. Meaningful comparison on the effect of the ceramic substrates configuration is provided in order to assess the performance of the device. Guidance on the identification and the selection of the best geometrical configurations of ceramic substrates are the main contributions of this work