Experimental investigation of energy dissipation in finite-amplitude standing waves
Atchley, Anthony A.
Coppens, Alan B.
MetadataShow full item record
Thermoacoustic engines are designed to perform optimally at one frequency. However, the thermoacoustic prime movers have been shown to generate highly nonlinear waveforms, in which a significant amount of the acoustic energy appears in higher harmonics. This condition reduces the overall efficiency of the engine. The harmonics can be suppressed. But does the suppression mean that more energy remains in the fundamental frequency? This question is the topic of this thesis. Finite-amplitude standing waves were generated in a standing wave tube. The steady state input acoustic power was compared to the steady state dissipated acoustic power for two configurations - an empty tube and an obstructed tube - over a wide range of input powers. The waveforms in the empty tube were rich in harmonics, whereas the obstruction suppressed the harmonics significantly. The results of the measurements indicate that suppression of the harmonics also suppresses the transfer of energy from the fundamental.
Showing items related by title, author, creator and subject.
Souza, Randy. (Monterey, California: Naval Postgraduate School, 1990-12);The behavior of Compact Free Electron Lasers is analyzed from a analytical and numerical point of view. The operating principles of the Compact FEL are reviewed with specific reference to electron dynamics, the gain ...
Coppens, Alan B.; Sanders, James V. (Acoustical Society of America, 1980-07);A perturbation expansion is formulated for the one‐dimensional, nonlinear, acoustic‐wave equation with dissipative term describing the viscous and thermal energy lossesencountered in a rigid‐walled, closed tube with large ...
Reducing stator current harmonics for a doubly-fed induction generator connected to a distorted grid Pierce, Seth J. (Monterey, California: Naval Postgraduate School, 2013-09);The Department of Defense (DoD) is increasing its demand for reliable renewable energy sources. The doubly-fed induction generator (DFIG) is widely used to extract electrical energy from wind and is a useful means for the ...