Thermo Acoustic Engines

abstract

Environmental priorities are forcing chloro¬-fluorocarbons out of market place thereby creating a new demand for cooling technologies. This paper presents an outcome of researches done to design, construct and evaluate a CFC free refrigeration system. A prototype Thermo acoustic cooling system utilizing high amplitude sound waves in an inert gas is discussed.

Thermo Acoustic Engines
A thermo acoustic engine converts some heat from a high Temperature heat source into acoustic power rejecting waste heat to a low temperature heat sink. The figure shown is very similar to appearance of a heat engine. The apparatus absorbs heat per unit time Qh from the heat source at high temperature Th rejects heat per unit time QC to a heat sink at low temperature TC and produces acoustic power W. According to first law of thermodynamics W + QC = Qh. The second law of thermodynamics show that the efficiency W/Qh is bounded by the carnot efficiency (Th-TC)/Th.