An algorithm for computing the 3-D oscillating flow field of the blade passage under the torsional vibra-tion of the rotor is applied to analyze the stability in turbomachines. The induced fiow field responding to bla...An algorithm for computing the 3-D oscillating flow field of the blade passage under the torsional vibra-tion of the rotor is applied to analyze the stability in turbomachines. The induced fiow field responding to blade vibration is computed by Oscillating Fluid Mechanics Method and ParaInetric Polynomial Method. After getting the solution of the unsteady flow field, the work done by the unsteay aerody natnic force acting on the blade can be obtained. The negative or positive work is the criterion of the aeroelastic stability Numerical results indicate that there are instabilities of the torsional vibration in some boency bands.展开更多
This paper presents the mutual time - marching method to predict the aeroelastic stability of an oscillating blade row in 3D transonic flow. The ideal gas flow through a blade row is governed by the time dependent Eul...This paper presents the mutual time - marching method to predict the aeroelastic stability of an oscillating blade row in 3D transonic flow. The ideal gas flow through a blade row is governed by the time dependent Euler equations in conservative form which are integrated by using the explicit monotonous second order accurate Godunov-Kolgan finite volume scheme and moving hybrid H-O grid. The structure analysis uses the modal approach and 3D finite element dynamic model of blade. The blade movement is assumed as a linear combination of the first modes of blade natural oscillations with the modal coefficients depending on time. To demonstrate the capability and correctness of the method, two experimentally investigated test cases have been selected, in which the blades had performed tuned harmonic bending or torsional vibrations (The lst and 4kyhstandard configurations of the "Workshop on Aeroelasticity in Turbomacbines" by Bolcs and Fransson, 1986). The calculated results of aeroelastic behaviour of the blade row (4th standard configuration), are presented over a wide frequency range under different start regimes of interblade phase angle.展开更多
文摘An algorithm for computing the 3-D oscillating flow field of the blade passage under the torsional vibra-tion of the rotor is applied to analyze the stability in turbomachines. The induced fiow field responding to blade vibration is computed by Oscillating Fluid Mechanics Method and ParaInetric Polynomial Method. After getting the solution of the unsteady flow field, the work done by the unsteay aerody natnic force acting on the blade can be obtained. The negative or positive work is the criterion of the aeroelastic stability Numerical results indicate that there are instabilities of the torsional vibration in some boency bands.
文摘This paper presents the mutual time - marching method to predict the aeroelastic stability of an oscillating blade row in 3D transonic flow. The ideal gas flow through a blade row is governed by the time dependent Euler equations in conservative form which are integrated by using the explicit monotonous second order accurate Godunov-Kolgan finite volume scheme and moving hybrid H-O grid. The structure analysis uses the modal approach and 3D finite element dynamic model of blade. The blade movement is assumed as a linear combination of the first modes of blade natural oscillations with the modal coefficients depending on time. To demonstrate the capability and correctness of the method, two experimentally investigated test cases have been selected, in which the blades had performed tuned harmonic bending or torsional vibrations (The lst and 4kyhstandard configurations of the "Workshop on Aeroelasticity in Turbomacbines" by Bolcs and Fransson, 1986). The calculated results of aeroelastic behaviour of the blade row (4th standard configuration), are presented over a wide frequency range under different start regimes of interblade phase angle.
