Change search
ReferencesLink to record
Permanent link

Direct link
General shell model for a rotating pretwisted blade
KTH, School of Engineering Sciences (SCI), Aeronautical and Vehicle Engineering, MWL Structural and vibroacoustics.
KTH, School of Engineering Sciences (SCI), Aeronautical and Vehicle Engineering, MWL Structural and vibroacoustics.ORCID iD: 0000-0002-3609-3005
KTH, School of Engineering Sciences (SCI), Aeronautical and Vehicle Engineering, MWL Structural and vibroacoustics.ORCID iD: 0000-0001-5760-3919
2013 (English)In: Journal of Sound and Vibration, ISSN 0022-460X, E-ISSN 1095-8568, Vol. 332, no 22, 5804-5820 p.Article in journal (Refereed) Published
Abstract [en]

A novel dynamic model for a pretwisted rotating compressor blade mounted atan arbitrary stagger angle using general shell theory and including the rotationalvelocity is developed to study the eigenfrequencies and damping properties of thepretwisted rotating blade. The strain-displacement relation and constitutive modelbased on the general (thick) shell theory are applied to bring out the strain energyof the rotating blade. Using the Hamilton’s principle, the variational form of thetotal energy is derived in order to obtain the corresponding weak form for thenumerical simulation. The model is validated by comparing to literature resultsand Ansys results, showing good agreement. Parametric analyses are carried outto study the influence of the rotation velocity, the stagger angle and the radius ofthe disk on the eigenfrequencies of the pretwisted blade. Proportional dampingis included into the proposed model to investigate the influence of rotational velocityon the damping characteristics of the pretwisted rotating blade system. It isshown that, due to inertial and Coriolis eects, damping decreases as the rotation velocity increases for the lower part of the velocity range considered and eitherdecreases or increases depending on the mode order for higher velocities. Furthermore,frequency loci veering as a result of the rotation velocity is observed.The proposed model is an ecient and accurate tool for predicting the dynamicbehavior of compressor blades of arbitrary thickness, stagger angle and pretwist,potentially during the early designing stage of turbomachinery.

Place, publisher, year, edition, pages
Elsevier, 2013. Vol. 332, no 22, 5804-5820 p.
Keyword [en]
Rotating pretwisted blade, Shell theory, Damping prediction
National Category
Applied Mechanics
URN: urn:nbn:se:kth:diva-101239DOI: 10.1016/j.jsv.2013.06.025ISI: 000323361000010ScopusID: 2-s2.0-84880923598OAI: diva2:546883
Swedish Energy Agency

QC 20130723

Available from: 2012-08-25 Created: 2012-08-25 Last updated: 2013-09-12Bibliographically approved
In thesis
1. Vibration Characteristics and Structural Damping of Rotating Compressor Blades
Open this publication in new window or tab >>Vibration Characteristics and Structural Damping of Rotating Compressor Blades
2012 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

Nowadays, the increasing demand on the high efficiency energy, low fuel consumption and environment friendly leads the turbomachinery to be operating under a critical high rotation speed at high temperature and pressure. This severe operation condition will definitely increase the probability of the occurrence of the high cycle fatigue. To reduce the risk of appearing high cycle fatigue, the structural damping of turbomachinery components has to be increased. Since the structural damping is always positive while the aerodynamic damping can be negative at some situation, increasing structural damping is nevertheless an interesting field in turbomachinery research. One efficient way of increasing damping is to treat damping material over the blade surface. Traditional damping materials, such as rubber, are not applicable in the severe operation environment. Therefore, hard coating material is applied due to its high stiffness and good sustainability in rough environments.

Numerical tools are developed to predict the structural damping of a dynamic rotating blade while varying several important designing parameters. Two types of rotating blades are modeled using the Hamilton’s principle: the straight blade by plate theory and pretwisted blade by shell theory. The extended Galerkin method and Chebyshev collocation method are applied for the numerical simulation, such as modal analysis and frequency response analysis. The parametric analysis is performed with respect to rotation speed, stagger angle, pretwisted angle, aspect ratio, etc. Proportional damping isused in all dynamic models to investigate the damping characteristics of the blades.

Alternatively, a multilayer rotating blade is modeled by a high order layerwise theory, where the validated results reveal the modal damping exchanges between modes dueto frequency loci veering and the influence of the damping configurations on the total damping of the multilayered structure. Finally, a commercial finite element software isused to predict the damping of a real compressor blade treated by the hard coating while varying the coating thickness and distributions.

Place, publisher, year, edition, pages
Stockholm: KTH Royal Institute of Technology, 2012. ix, 61 p.
Trita-AVE, ISSN 1651-7660 ; 2012:41
National Category
Applied Mechanics
urn:nbn:se:kth:diva-101241 (URN)978-91-7501-431-9 (ISBN)
Public defence
2012-09-07, K2, Teknikringen 28, KTH, Stockholm, 10:00 (English)
TrenOp, Transport Research Environment with Novel Perspectives

QC 20120827

Available from: 2012-08-27 Created: 2012-08-25 Last updated: 2013-04-11Bibliographically approved

Open Access in DiVA

fulltext(579 kB)947 downloads
File information
File name FULLTEXT02.pdfFile size 579 kBChecksum SHA-512
Type fulltextMimetype application/pdf

Other links

Publisher's full textScopusSciencedirect

Search in DiVA

By author/editor
Sun, JiaLopez Arteaga, InesKari, Leif
By organisation
MWL Structural and vibroacoustics
In the same journal
Journal of Sound and Vibration
Applied Mechanics

Search outside of DiVA

GoogleGoogle Scholar
Total: 947 downloads
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

Altmetric score

Total: 109 hits
ReferencesLink to record
Permanent link

Direct link