... 2011 blades finite element analysis Monte Carlo methods reduced order systems rotors statistical distributions vibrations The vibration of a multistage rotor has recently become an important area of research ( 1 2 3 4 5 6 ). The issue here is the impact of interstage coupling...

...Y.-J. Chan; D. J. Ewins Integral bladed disks (also known as blisks) are more widely used in modern aeroengine compressor designs because of the potential weight savings, but there are challenges in controlling the extreme vibration response levels in mistuned blisks, which are blisks with blades...

...Jean Thomassin; Huu Duc Vo; Njuki W. Mureithi Nonsynchronous vibration (NSV) is a particular type of aero-elastic phenomenon, where the rotor blades vibrate at nonintegral multiples of the shaft rotational frequencies. NSV behavior appears similar to off-design stall flutter but with a particular...

... Joint Propulsion Conference entitled “Wave Reflections in Subsonic Axial-Flow Turbomachines” (paper No. AIAA 92-3075), in which his earlier work was summarized and an explanation given for the way in which the reflecting waves can produce resonant vibrations of bladed disks. In addition, equations were...

... observed while comparing measurements across different groups in the RBR database because of space limitations. However, it is briefly noted that airfoil vibrations and loads in multiple rubs generally followed the pattern observed and documented for group 1 experiments in that several blade contacts were...

... for an academic rotor are presented to establish the validity of the technique. 22 07 2007 22 02 2008 08 04 2009 blades discs (structures) geometry reduced order systems rotors vibrations Mistuning refers to inevitable variations in blades’ properties, which arise during...

...T. Klauke; A. Kühhorn; B. Beirow; M. Golze Blade-to-blade variations of bladed disk assemblies result in local zoning of vibration modes as well as amplitude magnifications, which primarily reduces the high cycle fatigue life of aeroengines. Criteria were introduced to determine the level...

... sensible to the addition of small perturbations such as the aerodynamic forces. Since the determination of the aerodynamic vibrational correction (damping and frequency) requires knowing the mode shape, the aerodynamic corrections of the N a − 1 cluster modes are now unavoidably coupled together. Moreover...

...Jean Thomassin; Huu Duc Vo; Njuki W. Mureithi This paper investigates the role of tip clearance flow in the occurrence of nonsynchronous vibrations (NSVs) observed in the first axial rotor of a high-speed high-pressure compressor in an aeroengine. NSV is an aeroelastic phenomenon where the rotor...

... during vibration, causing the first axial bending mode to carry an increased, out of phase, torsional component. It is shown that this change in mode shape, compared to an unshrouded LSMB, can lead to destabilizing aerodynamic forces during vibration. At a sufficiently high mass flow, the destabilizing...

.... , 1998 , “ A Symmetry Approach to Extension of Flutter Boundaries via Mistuning .” J. Propul. Power 0748-4658 , 14 ( 3 ), pp. 354 – 366 . Imregun , M. , and Ewins , D. , 1984 , “ Aeroelastic Vibration Analysis of Tuned and Mistuned Blade Systems ,” Unsteady Aerodynamics...

... by comparison with experimental results. 13 10 2005 27 06 2006 25 01 2008 coordinate measuring machines blades rotors solid modelling finite element analysis mechanical engineering computing vibrations The relationship between CMM data and modal parameters of blades...

...J. Szwedowicz; R. Visser; W. Sextro; P. A. Masserey Numerical predictions of the forced vibration of a disk assembly including frictional effects between the shrouds are presented concerning engineering needs for the blade design process. Assuming a tuned disk assembly, numerical static, free...

...M. Nikolic; E. P. Petrov; D. J. Ewins The problem of estimating the mutual interaction of the effects of Coriolis forces and of blade mistuning on the vibration characteristics of bladed disks is addressed in this paper. The influence of different degrees of mistuning on forced response...

...E. P. Petrov A method has been developed to calculate directly resonance frequencies and resonance amplitudes as functions of design parameters or as a function of excitation levels. The method provides, for the first time, this capability for analysis of strongly nonlinear periodic vibrations...

...Sang-Ho Lim; Christophe Pierre; Matthew P. Castanier The forced vibration response of bladed disks can increase dramatically due to blade mistuning, which can cause major durability and reliability problems in turbine engines. To predict the mistuned forced response efficiently, several reduced...

... into account by including all stator bladerows of interest. The low engine-order excitation that could arise from a blocked passage was investigated next. It was shown that high vibration response could arise in such cases. 11 02 2004 03 06 2005 compressors turbomachinery Navier-Stokes...

...A. J. Sanders This paper describes the identification and prediction of a new class of nonsynchronous vibration (NSV) problem encountered during the development of an advanced design composite fan stator for an aircraft engine application. Variable exhaust nozzle testing on an instrumented engine...

...E. P. Petrov; D. J. Ewins An efficient method for analysis of nonlinear vibrations of mistuned bladed disk assemblies has been developed. This development has facilitated the use of large-scale finite element models for realistic bladed disks, used hitherto in analysis of linear vibration...

... between the observed structures and those from vortex shedding in some other physical situations, such as the vortex wakes shed from cylinders and airfoils in sinusoidal heaving motion in low-speed flow. The established field of vortex-induced vibration has provided a developed classification scheme...