Thermoacoustic Engine - How do these Hofler Tubes Generate Sound? [video]
Authors
Denardo, Bruce
Subjects
Advisors
Date of Issue
2015-06
Date
Published on Jun 1, 2015
Publisher
Naval Postgraduate School, Monterey, California
Language
en_US
Abstract
This thermoacoustic engine, also known as a Hofler Tube, has no moving parts. A strong temperature gradient across closely spaced plates in the middle of the tube creates a thermodynamic cycle of oscillating air that produces sound This small thermoacoustic sound source was invented by Naval Postgraduate School Professor Tom Hofler and built by NPS Engineer Jay Adeff. The hofler tube can use a flame or electrical heat source at 308 °C to produce sound pressure levels as high as 149 dB SPL at 930 Hz. The heat power to radiated sound power efficiency has been measured to be 2.8%. Sufficient information has been included so that others may construct the device. Dr. Bruce Denardo of the Naval Postgraduate demonstrates a Hofler Tube during a 2015 Maos visit.
Type
Video
Description
NPS Physics EDU
Series/Report No
Department
Physics
Organization
Naval Postgraduate School (U.S.)
Identifiers
NPS Report Number
Sponsors
Funder
Format
Duration: 3:57 Filesize 42.9 MB
Citation
Distribution Statement
Rights
This publication is a work of the U.S. Government as defined in Title 17, United States Code, Section 101. Copyright protection is not available for this work in the United States.