Modeling, design, and development of novel thermagoustic and therporaoustic systems

想象一下，一台使用环保气体的冰箱，而不是目前破坏环境的CFCs(氯氟烃)和HFCs(氢氟烃)。想象一下，这台冰箱是如此安静，以至于听不见。进一步想象一下，昂贵的压缩机被一个单独的移动部件取代，这使得冰箱本身就坚固可靠。这样的冰箱是存在的，它利用了热声技术。典型的热声发动机利用低品位热源(例如，余热和太阳能)并将其转换为声能。相比之下，典型的热声制冷机利用声源产生冷却效果。问题是，热声系统目前的效率很低，因此它们只在利基应用中才能找到，比如在太空中，或者在本和曾傑瑞的冰淇淋的环保宣传中。 这项研究工作提出了热声学的两个新分支，即热磁声学(热磁声学)和热孔声学(热孔声学)，它们代表着在追求更有效的热声器件方面向前迈出的重要一步。在热声学中，磁力控制热声的运行，而在热声学中，声波通过多孔介质传播，以提高热声效率。热声和热声器件在几个领域展示了它们的潜在应用：电子制冷(例如高频压电致冷器)、低温应用(例如斯特林制冷器)、远程空间应用(例如NASA的航天飞机)、低温应用(例如热声-斯特林系统)、制冷(例如太阳能驱动的热声制冷机)和车辆应用的混合系统(例如热电-热声制冷系统)。 这项研究的结果将导致更有效的热声装置设计，从而有助于商业化。考虑到热声技术的起步和潜在的消费市场，加拿大有潜力成为这项技术商业化的领先者，特别是如果加拿大国内取得重大能效突破的话。

Imagine a refrigerator that uses environmentally friendly gases instead of the current environmentally damaging CFCs (chlorofluorocarbons) and HFCs (hydrofluorocarbons). Imagine this refrigerator being so quiet that it cannot be heard. Further imagine that the costly compressor is replaced with a single moving part that makes the refrigerator inherently robust and reliable. Such a refrigerator exists and it utilizes thermoacoustics. A typical thermoacoustic engine utilizes a low grade heat source (e.g., waste heat and solar energy) and converts it to acoustic power. In contrast, a typical thermoacoustic refrigerator utilizes an acoustic source to produce a cooling effect. The catch is that thermoacoustic systems are currently inefficient, thus they have only found in niche applications such as in space or in environment friendly promotions by Ben and Jerry's Ice Cream. This research work proposes two novel branches of thermoacoustics, namely, thermagoustics (thermal-magnetic-acoustics) and therporaoustics (thermal-porous-acoustics) which represent major steps forward in the pursuit of more efficient thermoacoustic devices. In thermagoustics magnetic force controls thermoacoustic operation while in therporaoustics the acoustic sound waves travel through a porous medium to enhance thermoacoustic efficiencies. Thermagoustic and therporaoustic devices exhibit their potential application in several areas: electronic cooling (e.g., high frequency piezoelectric cooler), low-temperature applications (e.g., Stirling cryo-cooler), remote space applications (e.g., NASA's space shuttle), cryogenic applications (e.g., Thermoacoustic-Stirling system), refrigeration (e.g., solar powered thermoacoustic refrigerator), and hybrid systems (e.g., thermoelectric-thermoacoustic cooling systems) for vehicle applications. The outcomes of this research will lead to more efficient thermoacoustic device designs, thus aiding commercialization. Given the infancy of thermoacoustics and the potential consumer market, Canada has the potential to be a leader in the commercialization of this technology, especially if major efficiency breakthroughs are developed within Canada.