Ph.D. Thesis Defense by Robert Stowers Reid
Monday, August 23, 1999

(Dr. Prateen Desai, advisor)

"Open Cycle Thermoacoustics"


A new type of thermodynamic device combining a thermodynamic cycle with the externally applied steady flow of an open thermodynamic process has been experimentally demonstrated.  Gas flowing through this device can be heated or cooled in a series of semi-open cyclic steps.  The superposition of open and cyclic flows makes possible the elimination of some or all of the heat exchangers (with their associated irreversibility).  Heat is directly exchanged with the process fluid as it flows through the device when operating as a refrigerator, producing a staging effect that tends to increase First Law  thermodynamic efficiency.  An open-flow theroacoustic refrigerator was built to demonstrate this concept.  Several approaches are presented that describe the physical characteristics of this device.  Tests have been conducted on this refrigerator with good agreement with a proposed theory.