New Energy Conversion Device SATEC - A New Understanding of Heat Engine

固体壁面与振荡气体之间的热相互作用产生了多种热声现象，如气体自激振荡和声学热泵。在声热声能量转换（SATEC）系统中，热流和功流之间的转换发生在叠片结构中，本文首先提出了热声能量转换声放大系统中模态选择的新的理论规律。热声系统的研究思路可应用于斯特林发动机等通用发动机。斯特林发动机由于其固有的卡诺效率可逆性，作为一种有吸引力的能量转换装置，引起了科学工程师的极大兴趣。21年前，Ceperley提出了一种无活塞斯特林发动机，其中声波取代了通常的运动活塞。他的想法使制造一种新型的热机和冷却器成为可能，没有滑动密封。其次，我们展示了一个声学冷却器的原型，使用斯特林循环的行波具有高声阻抗热声诱导在一个环形管。该管没有调谐和移动部件，而是夹在两个热交换器之间的一对堆栈：一个放大声功率，放大的波提供激励能量，以直接在第二个堆栈内泵送热量。该样机在230 W的功率下，利用0.25MPa的He-Ar混合气体，克服了环境空气的热负荷，使换热器从室温冷到-27℃。由于它使用由几个部件和对环境无害的工作流体组成的极其简单的硬件，因此冷却装置可能是传统冷却系统等应用的强大工具。

Thermal interactions between solid walls and oscillating gas produce a rich variety of thermoacoustic phenomena such as self-sustained gas oscillations and acoustic heat pumping. The conversion between heat flow and work flow occurs in a stack of plates, where Sound is Amplified by Thermoacoustic Energy Conversion(SATEC).Firstly we propose new thermodynamical law governing the mode selection in such themoacoustic engines. The ideas obtained in thermoacoustic sysytem may be applied to general engines such as Stirling engines. Stirling engine has arisen considerable interest of scientific engineers as an attractive energy conversion device because of its intrinsically reversibleness with the Carnot efficiency. 21 years ago Ceperley proposed a pistonless Stirling engine in which acoustic waves replace usual moving pistons. His idea makes it possible to produce a new type of heat engine and cooler having no sliding seals.Secondary we demonstrate an acoustic cooler prototype which uses Stirling cycles executed by the traveling wave having a high acoustic impedance thermoacoustically induced in a looped tube. The tube has no tuning and moving parts but a pair of stacks sandwiched between two heat exchangers: one amplifies the acoustic power and the amplified wave supplies the motivating energy to pump heat directly within the second stack. The prototype powered by 230W of heat could oool a cold heat exchanger from ambient temperature to -27℃ overcoming a heat load from the surrounding air by using a He-Ar mixture gas pressurized to 0.25MPa. Because it uses an extremely simple hardware consisting of a few parts and environmentally harmless working fluids, the cooling device is potentially a powerful tool for applications such as conventional cooling systems.