Acoustic and thermal packaging of small gas turbines for portable power

To meet the increasing demand for advanced portable power units, for example for use in personal electronics and robotics, a number of studies have focused on portable small gas turbines. This research is concerned with gas turbine generator units in the 1 kW range. The compact and small-scale architecture of the portable gas turbine engine poses major challenges in the acoustic treatment that is required to attenuate the broadband and tonal noise of the high-speed turbomachinery. The challenge in the thermal management is the relatively large required cooling mass flow and the short flow mixing length, constrained by package size considerations. The objective is to conceive a proof-of-concept engine package with exhaust temperatures of 60 °C and a noise signature below 50 dBA at a distance of 7 m. Various liner materials and configurations were investigated in an anechoic chamber using a modular silencer test rig. Acoustic liners based on porous fiber material were developed for both cold intake and hot exhaust gas silencers to reduce the broadband noise. The source noise simulations combined with the measured silencer noise reduction show noise levels below 50 dBA in all directions. A parametric silencer configuration study was carried out to determine the trade-off between liner volume, surface area, and noise reduction. The liner material was demonstrated to withstand hot gas conditions at 700 °C.

Department dc:contributor.department

Massachusetts Institute of Technology. Dept. of Aeronautics and Astronautics.

Grantor dc:publisher

Massachusetts Institute of Technology

Year dc:date.issued

2009

Author dc:creator

• Tanaka, Shinji, S.M. Massachusetts Institute of Technology

Advisor dc:contributor.advisor

• Zoltán S. Spakovszky.

• Aeronautics and Astronautics.

Statement dc:rights

• M.I.T. theses are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission. See provided URL for inquiries about permission.

Licence dc:rights.uri

• http://dspace.mit.edu/handle/1721.1/7582

Language dc:language.iso

eng

Handle dc:identifier.uri

http://hdl.handle.net/1721.1/51648

OAI identifier oai:identifier

oai:dspace.mit.edu:1721.1/51648