ASA 126th Meeting Denver 1993 October 4-8

2aPAa9. Thermoacoustic termination for a traveling wave tube.

John N. Kordomenos

Dept. of Phys., Univ. of Mississippi, University, MS 38677

Anthony A. Atchley

Naval Postgraduate School, Monterey, CA 93943

Richard Raspet Henry E. Bass

Univ. of Mississippi, University, MS 38677

A theory for thermoacoustics of traveling waves has been developed and presented previously by Raspet et al. [J. Acoust. Soc. Am. 93, 2278 (A) (1993)]. In this paper, experimental results are compared with predictions of this theory. The experiment consisted of measuring the pressure reflection coefficient of a thermoacoustic termination located at one end of a 20-m-long, 5-cm-i.d. tube. The termination consisted of a hot heat exchanger, a 5-cm-long, square pore stack, a cold heat exchanger, and a cold end. The temperature of the hot heat exchanger was maintained near room temperature. The temperature of the cold end was held close to liquid nitrogen temperature (-77 K). Measurements were made for frequencies ranging from 300 to 1200 Hz, and for different cold end impedances. There is good agreement between the measured and predicted results. [This work was supported by the Office of Naval Research.]