Change search
ReferencesLink to record
Permanent link

Direct link
Experimental investigation of mode shape sensitivity of an oscillating LPT cascade at design and off-design conditions
KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Heat and Power Technology.
KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
2006 (English)In: Proceedings of the ASME Turbo Expo 2006, Vol 5, Pts A and B, 2006, 1151-1163 p.Conference paper (Refereed)
Abstract [en]

The effect of negative incidence operation on mode shape sensitivity of an oscillating low pressure (LP) turbine rotor blade row has been studied experimentally. An annular sector cascade has been employed in which the middle blade has been made oscillating in controlled three-dimensional rigid-body modes. Unsteady blade surface pressure data were acquired at midspan on the oscillating blade and two pairs of non-oscillating neighbor blades and reduced to aeroelastic stability data. The test program covered variations in reduced frequency, flow velocity and inflow incidence; at each operating point a set of three orthogonal modes was tested such as to allow for generation of stability plots by mode recombination. At nominal incidence it has been found that increasing reduced frequency has a stabilizing effect on all modes. The analysis of mode shape sensitivity yielded that the most stable modes are of bending type with axial to chordwise character whereas high sensitivity has been found for torsiondominated modes. Negative incidence operation caused the flow to separate on the fore pressure side. This separation was found to have a destabilizing effect on bending modes of chordwise character whereas an increase in stability could be noticed for bending modes of edgewise character. Variations of stability parameter with inflow incidence have hereby found being largely linear within the range of conditions tested. For torsion-dominated modes the influence on aeroelastic stability was close to neutral.

Place, publisher, year, edition, pages
2006. 1151-1163 p.
National Category
Energy Engineering
URN: urn:nbn:se:kth:diva-42240ISI: 000242368000122ScopusID: 2-s2.0-33750812460ISBN: 0-7918-4240-1OAI: diva2:446426
51st ASME Turbo Expo Location: Barcelona, Spain, Date: MAY 06-11, 2006

QC 20150710

Available from: 2011-10-07 Created: 2011-10-06 Last updated: 2015-07-10Bibliographically approved

Open Access in DiVA

No full text


Search in DiVA

By author/editor
Vogt, Damian M.Fransson, Torsten H.
By organisation
Heat and Power TechnologyEnergy Technology
Energy Engineering

Search outside of DiVA

GoogleGoogle Scholar
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

Total: 23 hits
ReferencesLink to record
Permanent link

Direct link