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3D flutter analysis of 11th standard configuration using ANSYS CFX

Kubitz L., Rzadkowski R., Kunicka Z.

Zeszyty Naukowe. Cieplne Maszyny Przepływowe - Turbomachinery / Politechnika Łódzka

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2014

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nr 146

119--140

EN

In this study, numerical simulations of 3D viscous flutter were performed and compared with the available experimental results using ANSYS CFX. The calculations were carried out for bending oscillations of the cascade known as the Eleventh Standard Configuration. The developed numerical algorithm solves the 3D Reynolds-averaged Navier-Stokes equation together with k-ω, SST, S-A models using the explicit monotonous second-order accurate finite-volume scheme and moving hybrid H-O structured grid. Comparison of the calculated and the experimental results for the Eleventh Standard Configurations has shown good quantitative and qualitative agreement for local performances (unsteady pressure amplitude and phase distribution) at off-design conditions, benchmark solutions are provided for various values of the inter-blade phase angle 0, 180, -90, 90 deg.

2

Flutter analysis of IV standard configuration cascades, direct integration method

Rządkowski R., Kubitz L.

Mechanics and Mechanical Engineering

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2011

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Vol. 15, nr 3

333-341

EN

A three-dimensional nonlinear time-marching method and numerical analysis for aeroelastic behaviour of oscillating blade row has been presented. The approach is based on the solution of the coupled fluid-structure problem in which the aerodynamic and structural equations are integrated simultaneously in time. Thus providing the correct formulation of a coupled problem, as the interblade phase angle at which a stability (or instability) would occur, is a part of the solution.

3

Algorytm obliczeniowy drgań swobodnych łopatki wirnikowej

Kyzioł L., Kubitz L.

Zeszyty Naukowe Akademii Marynarki Wojennej

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2008

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R. 49 nr 2 (173)

25-42

PL

Przedstawiono podstawowe zagadnienia związane z zastosowaniem metody elementów skończonych (MES) w analizie drgań swobodnych łopatki wirnikowej z wykorzystaniem elementów izoparametrycznych. Opracowano algorytm, w oparciu o który napisano program służący do obliczania częstości drgań własnych, modelując konstrukcję elementem izoparametrycznym płaskim czterowęzłowym trójwymiarowym, ośmiowęzłowym lub dwudziestowęzłowym.

EN

The paper presents the basic issues related to use of finite element method for analysis of free vibrations of rotor blade with isoparametric elements. An algorithm was developed and was used to write a program to calculate frequency of own vibrations, modelling the structure with three-dimensional four-knot, eight-knot or twenty-knot isoparametric element.

4

Natural frequencies of tuned and mistuned bladed discs on a shaft

Rządkowski R., Drewczyński M., Kubitz L.

TASK Quarterly : scientific bulletin of Academic Computer Centre in Gdansk

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2006

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Vol. 10, No 3

275-289

EN

The dynamic behaviour of a rotor consisting of two tuned and mistuned bladed discs on a solid shaft is considered. The effect of the shaft's flexibility on the dynamic characteristics of the bladed discs and the coupling effects between the shaft and bladed disc modes are investigated. Results show clearly the coupling effects in a bladed disc-shaft system. Interference diagrams are developed, from which the dynamic behaviour of a bladed disc can be predicted for varying flexibility relationships between solid shafts and bladed discs. The global rotating mode shapes of flexible tuned and mistuned bladed disc-shaft assemblies are calculated. Rotational effects, such as centrifugal stiffening, are accounted for and all the possible couplings between the flexible parts are allowed. Calculated natural frequencies obtained from the blade, the bladed disc and the shaft with two discs are checked to discover resonance conditions and coupling effects. It is shown that blade mistuning strongly affects the interaction between flexible bladed discs and a flexible shaft. This interaction affects the flexible bladed disc modes and is not restricted to the modes with zero, one and two nodal diameters. The torsional frequency of the shaft with two bladed discs is coupled with the zero nodal diameter modes of the single bladed discs. It is shown that including the shaft in the bladed discs model is important from the designer's point of view and may alter the spectrum of frequencies considerably.