Acoustical Characteristics of Aircraft Panels

↓ Direkt till sidans innehåll
↓ Direkt till sidans sekundära innehåll (sidomenyn)

Search: WFRF:(Liu Pan) > (2005-2009) > Acoustical Characte...

Details
MARC

Liu, Bilong,1970-KTH,Farkost och flyg (author)

Acoustical Characteristics of Aircraft Panels

BookEnglish2006

Publisher, publication year, extent ...

Stockholm :KTH,2006
23 s.
electronicrdacarrier

Numbers

LIBRIS-ID:oai:DiVA.org:kth-4102
https://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-4102URI

Supplementary language notes

Language:English
Summary in:English

Part of subdatabase

SwePubSwePub

Classification

Subject category:vet swepub-contenttype
Subject category:dok swepub-publicationtype

Series

TRITA-AVE,1651-7660 ;2006:60

Notes

QC 20100908
A deterministic approach based on a modal expansion and modal receptance method has been developed to evaluate the airborne sound insulation of aircraft panels with stringer and ring frame attachments. Furthermore, this method was extended to predict the noise radiation of stiffening panel subjected to TBL excitation. This approach integrates with the fast and accurate methods in evaluating the modal excitation terms and modal radiation efficiency. Based on these advantages, the effects of the curvature, overpressure, stringers, ring frames, hydrodynamic coincidence, composite structures and structural dissipation on the acoustical properties of a typical aircraft panel are able to be investigated efficiently.Theoretic predictions were compared with laboratory measurements conducted on both model structures and aircraft panels. It was found that a small curvature may result in significant deterioration of the sound transmission loss at frequencies of interest. Unlike a flat uniform panel, the theoretical prediction for curved panels from the infinite model can not provide good agreement with the measurement close to and well below the ring frequency. However, in this frequency range, the finite model has been proved to be applicableFor the large curved airplane panels studied here, it was found that the ring frames have little influence on sound transmission loss in the frequency range of interest. However the stringers may have considerable influence on sound transmission loss. The stringer improves this for a curved panel around the ring frequency, but it may result in a potential deterioration of the sound transmission loss above the ring frequency. In this study it is evident that the sound transmission loss of the composite skin attached with composite stringers is lower than that of the metallic panel attached with metallic stringers.At frequencies higher than the corresponding ring frequency of the curved panel, both experiment and theoretical prediction reveal that the overpressure at the concave side tends to reduce the sound transmission loss at the rate of about 0.5dB /10000 Pa. While at lower frequencies, say well below the ring frequency, the overpressure may increase or reduce sound transmission loss of a finite panel, depending on the shift of the resonant frequencies resulting from the overpressure.For TBL excitation, numerical investigation reveals that the panel with the ring frames behaves more like a sub-panel between two frames. Below 500Hz, the ring frames slightly enhance the sound radiation while dramatically increasing it around 1.3kHz. The TBL forcing field excites the same vibration lever for the panel with and without ring frame attachments, but the modes excited for the panel with ring frames radiate more sound. Unlike the ring frames, the stringers increase sound radiation below 1kHz. Above 1kHz, the sub-panels between two bays respond independently and the stringer effects is therefore not obvious.

Subject headings and genre

TEKNIK OCH TEKNOLOGIER Maskinteknik Strömningsmekanik och akustik hsv//swe
ENGINEERING AND TECHNOLOGY Mechanical Engineering Fluid Mechanics and Acoustics hsv//eng
Acoustics
sound transmission loss
stiffener
stiffening
aircraft panel
cylindrical shell
turbulent boundary layer
TBL
noise
sound radiation
Acoustics
Akustik

Added entries (persons, corporate bodies, meetings, titles ...)

Feng, LepingKTH,Farkost och flyg(Swepub:kth)u1jdv1sx (thesis advisor)
Pan, Jie,Prof.The University of Western Australian (opponent)
KTHFarkost och flyg (creator_code:org_t)

Internet link

Find in a library

Acoustical Characteristics of Aircraft Panels (Search the publication in LIBRIS)

To the university's database

Find more in SwePub

By the author/editor: Liu, Bilong, 197 ...; Feng, Leping; Pan, Jie, Prof.

About the subject

ENGINEERING AND TECHNOLOGY: ENGINEERING AND ...; and Mechanical Engin ...; and Fluid Mechanics ...

Parts in the series: TRITA-AVE,

By the university: Royal Institute of Technology

Search outside SwePub

Extend your search to:: Google; Google Book Search; Google Scholar

Kungliga biblioteket hanterar dina personuppgifter i enlighet med EU:s dataskyddsförordning (2018), GDPR. Läs mer om hur det funkar här.
Så här hanterar KB dina uppgifter vid användning av denna tjänst.

LIBRIS.kb.se