DE102009010375A1 - Apparatus and method for determining the vibration behavior of an integrally bladed stator or rotor disk - Google Patents

Abstract

In a method of detecting vibration behavior of an integrally bladed stator or rotor disk (10), a first phase relationship and a second phase relationship are defined. A first blade (14) of the stator or rotor disk (10) is excited with the first predetermined phase relationship to a reference signal. A second blade (15) of the stator disk (10) is excited with the second predetermined phase relationship with the reference signal. An oscillation of the stator or rotor disk (10) is detected in temporal relation to the reference signal.

Description

The The present invention relates to a device and a Method for detecting the vibration behavior of the individual blades an integrally bladed stator or rotor disc and / or the entire integrally bladed stator or rotor disk for a compressor or a turbine stage of a gas turbine or a Turbine engine for a mobile or stationary Application.

rotor discs for compressor or turbine stages of gas turbines or Turbine engines for mobile or stationary Applications have long been made up of several separately manufactured pieces built. In particular, the rotor blades were form-fitting connected to a disc or hub. Increasingly, however, they are becoming integral used bladed rotor disks, first in compressor stages, then in low-pressure turbines and now also in high-pressure turbines. Sometimes The rotor blades are manufactured separately and then, for example cohesively by means of a friction welding process connected to the hub. Similarly, becoming increasingly Also stator blades are bladed integrally.

in the Unlike built stator or rotor disks have integral bladed stator or rotor disks (English: bladed disks; Blisks) a pronounced system natural vibration behavior on. Since the blades of an integrally bladed stator Rotor disc never have completely identical properties, their natural frequencies differ slightly in mechanical vibrations, typically by a few percent or less. For this slightly different vibration behavior resulting in resonances strong different vibration amplitudes of the individual blades. These amplitude peaks, typically around a factor of 2 to 5, but sometimes more, must be quantitative be recorded on a test bench.

animated Among other things, vibrations of a rotor disk are caused by the gas stream in which they rotate is not homogeneous and not even is perfectly axisymmetric. By neighboring components, in particular upstream or downstream of the rotor disk arranged stator blades or other devices is the gas flow spatially modulated. Every single scoop of the rotating Rotor disc is therefore varying, in particular oscillating Exposed to forces. During a full turn the rotor disk are all the rotor blades approximately the same, equally as a function of time varying forces but depending on its position on the rotor disk at different times. In other words the time-dependent forces on the individual rotor blades a rotating rotor disc out of phase with each other. The same applies to the forces acting on the individual stator blades a stator disc act.

The item "Traveling wave excitation and optical measurement techniques for now-contacting investigation of bladed disk dynamics" by JA Judge et al. describes an acoustic excitation of the blades of an integrally bladed rotor disk by means of a respective loudspeaker. The individual loudspeakers are driven with the same signal but delayed by different phases. As a result, the excitation of the rotor blades of a rotating rotor disk is simulated by their encounters with adjacent stator blades or other stationary components. Resultant oscillations of the rotor disk are selectively measured quantitatively by means of single-point laser vibrometry (SPLV) or qualitatively over a large area by means of speckle interferometry (English: Speckle Pattern Interferometry).

The WO 2000/003197 (published in German as DE 699 34 474 T2 ) describes excitation of a wave generated by a vibration excitation source and imaging of the wave propagating on a diffuse reflecting surface by means of a reference wavefront modulated in synchronism with the vibration excitation source.

A The object of the present invention is to provide a device a method and a computer program for determining a vibration behavior to provide an integrally bladed stator or rotor disc.

These Task is by the objects of the independent Claims solved.

further developments are indicated in the dependent claims.

Various Embodiments of the present invention are based on the idea of paddling a stator or rotor disk with different or also same predetermined phase relationships relative to a reference signal excite and a resulting vibration of the stator or rotor disk in temporal relation to the reference signal. The temporal Reference of the detection of the oscillation to the reference signal, for example produced by that discrete points in time, to which measured values are detected, one or more predetermined phase relationships (mod 2π) to the reference signal.

The vibration is detected, for example, by laser vibrometry, with one after the other - or when using multiple laser vibrometer simultaneously or partially simultaneously - the vibration is detected at a plurality of predetermined points or locations on the stator or rotor disk. For this purpose, a scanning laser vibrometer can be used, as offered for example by the company Polytec in some variants.

each Bucket can be excited by an associated sound generator, which is coupled to the blade via air or another fluid.

Around Make sure all blades with the same amplitude and as accurately as possible with the respective predetermined phase relationship can be stimulated, the sound generator and its upstream Facilities are calibrated. This is first a Microphone in a defined spatial arrangement relative brought to a sound generator to be calibrated. Under a Microphone is here and below any means of detecting to understand a sound pressure and / or a phase of sound. The sound generator is controlled to produce sound that is detected by the microphone. Based on a comparison of actual and Target values are the sound pressure and / or the phase of the sound generator calibrated generated sound. Such a calibration can be done automatically. In a calibration process, each sound generator for several frequencies are calibrated. The calibration factors thus obtained are stored, for example, in the form of an array. alternative or in addition, each sound generator before and / or calibrated after using a specific frequency for this become.

embodiments Depending on the application, the present invention may be a Have a number of advantages. In particular, a fast and partially or fully automated determination of Amplitude overshoot for a wide frequency range and allows or simplifies numerous phase configurations. By detecting the oscillation in temporal relation to the reference signal, to which the excitations of the stator or rotor blades in predetermined Phase relations can also be found in a sequential Sampling of many measuring points Phase relationships between the oscillations be detected at the individual measuring points. This is not only locally, but for the entire stator or rotor disk a quantitative and not only qualitative analysis of the vibration behavior possible. It can also be integrated into an automated process Calibration enables precise excitation and thus a high accuracy of the measurement results.

Brief description of the figures

following Be embodiments with reference to the attached Figures explained in more detail. Show it:

1 a schematic representation of an apparatus for detecting a vibration behavior of an integrally bladed rotor disk;

2 a schematic representation of a section of a clamping plate; and

3 a schematic flow diagram of a method for detecting a vibration behavior.

Description of the embodiments

1 shows a schematic representation of an integrally bladed rotor disk 10 with a plurality of rotor blades 14 . 15 and a device 20 for detecting a vibration behavior of the rotor disk 10 , The outlines of the rotor disk 10 are shown with a broken line, since they are not part of the device 20 is. The diameter of the rotor disc 10 as well as the number, shape and size of the individual rotor blades 14 . 15 are arbitrary and can from the representation in 1 differ significantly.

The device 20 includes a reference signal device 30 for receiving or generating a reference signal having a predetermined frequency. Furthermore, the device comprises 20 several excitation devices 40 . 50 , for reasons of clarity in 1 only two are shown. A first excitation device 40 is a first rotor blade 14 assigned, a second excitation device 50 is a second rotor blade 15 assigned. For many applications, it is advantageous if the number of excitation devices 40 . 50 the number of rotor blades 14 . 15 the rotor disk to be examined 10 corresponds and each rotor blade 14 . 15 an excitation device 40 . 50 assigned. In this case, for example, all excitation devices 40 . 50 as much as possible the same.

Every stimulation device 40 . 50 includes a delay device 42 . 52 whose input is connected to a signal output of the reference signal device 30 is coupled to a reference signal from the reference signal device 30 to recieve. An output of the delay device 42 . 52 is with an input of an amplifier 44 . 54 coupled. An output of the amplifier 44 . 54 is with a sound generator 46 . 56 coupled. Every sound generator 46 . 56 can be like in 1 be indicated circular or identify another shape. Everyone Sound generator is for example an electrodynamic, electrostatic, magnetostatic, electromagnetic or ferroelekrischer speaker, a plasma tweeter or other electro-acoustic transducer for generating sound or ultrasound. Carriers, brackets or other means for holding the sound generator 46 . 56 are in 1 not shown. However, an example will be made below with reference to FIG 2 shown.

Furthermore, the device comprises 20 a microphone 60 or another device for detecting a sound pressure and / or a phase of sound. The microphone 60 is trained to listen to every sound generator 46 . 56 to be approached or in a predetermined spatial arrangement relative to any sound generator 46 . 56 to be arranged. Instead of a microphone 60 a plurality of microphones may be provided, which should generally be calibrated at least relative to one another.

The device 20 further includes a scanning laser vibrometer 70 or another means for detecting the swing of the rotor disk 10 at several measuring points 71 . 72 , In the case of a laser vibrometer, a laser beam becomes 78 one after the other on the measuring points 71 . 72 directed. The number and arrangement of the measuring points 71 . 72 can be almost arbitrary to the rotor disk 10 and the vibration behavior to be examined are adapted. To accelerate the measuring process can also have multiple vibrometer 70 to be used simultaneously. A signal input of the vibrometer 70 is with the reference signal output of the reference signal device 30 coupled. Although the vibrometer 70 in 1 next to the rotor disk 10 is an arrangement near the axis of the rotor disk 10 optimal in many cases. In the 1 separately shown reference signal device 30 can be part of the vibrometer 70 be.

The device 20 further includes a controller 80 with a processor 82 and a memory 84 , The control 80 is with the reference signal device 30 , the delay devices 42 . 52 and the amplifiers 44 . 54 excitation devices 40 . 50 , the vibrometer 70 and optionally also the microphone 60 coupled. In the store 84 or several times saving the controller 80 An operating system and / or a computer program (in the form of software or firmware) may expire on the processor 82 as well as parameters of a measuring program, as described below on the basis of 3 is shown, and calibration factors are stored. The parameters include, for example, amplitudes, frequencies and phase relationships or intervals of frequencies or phase relationships and step sizes with which these are to be changed. For example, calibration factors for sound pressure and / or phase may be in the form of an array for all sound generators 46 . 56 and several frequencies are stored.

The control 80 is configured to the reference signal device 30 , the delay devices 42 . 52 , the amplifier 44 . 54 and the vibrometer 60 to control. In particular, the controller 80 formed to the reference signal device 30 specify a frequency for a reference signal to pass through the delay means 42 . 52 to specify delays or phase relationships to be generated by the amplifiers 44 . 54 to set gain factors to be generated, and measurement points 71 . 72 and other parameters to the vibrometer 70 transferred to. Furthermore, the controller 80 be configured to receive measurement signals or measurement data from the microphone 60 and from the vibrometer 70 to recieve.

2 shows a schematic representation of a section of a section through rotor blades 14 . 15 a rotor disk, a clamping plate 90 and sound generators 46 . 56 , The section shown is a section along a circular cylindrical surface parallel to the axis of a rotor disks, whose components are the rotor blades 14 . 15 are. The clamping plate 90 has several brackets 92 on each of which a sound generator 46 . 56 is arranged. The shape of the individual brackets 92 is to the rotor blades 14 . 15 and their spaces adapted. The clamping plate 90 with the brackets 92 is as stiff as possible and / or designed with vibration absorbers to oscillate in the process described below in the least possible extent itself.

The above based on the 1 and 2 illustrated device 20 can be modular, so for example, the number of excitation devices 40 . 50 and the arrangement of the sound generator 46 . 56 changed and to different rotor discs 10 can be adjusted. The arrangement and spatial orientation of the sound generator 46 . 56 For example, it can be changed manually or by servo motor. A radial displaceability of the individual sound generators, for example on rails, can also be advantageous in the case of the calibration carried out in the context of the method described below.

3 FIG. 12 shows a schematic flowchart of a method for detecting a vibration behavior of an integrally bladed rotor disk or similar component of a compressor, turbine, or other component of a gas turbine engine. Although this procedure also with other than the above based on the 1 and 2 illustrated devices and devices is executable, In the following, reference numerals will be given by 1 and 2 used to improve the intelligibility of the text.

At a first step 101 a frequency is defined at which the vibration behavior of an integrally bladed rotor disk is to be detected. In a second step 102 phase relationships are defined. In particular, for each rotor blade 14 . 15 the rotor disc to be examined defines a phase relationship. The frequency and the phase relationships result from the number of rotor blades 14 . 15 the rotor disk 10 , from the number and arrangement of the stator blades or other devices, in the intended use of the rotor disc 10 in the vicinity, in particular upstream, are arranged, as well as from a fictitious rotational speed of the rotor disk 10 ,

At a third step 103 becomes a reference signal with the one at the first step 101 generated defined frequency, for example, from a reference signal device 30 ,

At a fourth step 104 is from a sound generator 46 . 56 Sound according to the reference signal, especially with the first step 101 defined frequency generated. At a fifth step 105 This sound is from a microphone 60 or another device for detecting a sound pressure and / or a phase of sound detected. At a sixth step 106 a calibration factor for the sound pressure or the phase is determined. The calibration factor, for example, goes into that of the associated delay device 42 . 52 generated delay of the reference signal or in the of the associated amplifier 44 . 54 generated gain of the delayed reference signal. The calibration factor is determined, for example, by changing it until the sound pressure or the phase of the microphone 60 detected sound corresponds to a predetermined target value. In this case, the fourth step 104 , the fifth step 105 and the sixth step 106 run continuously at the same time.

The fourth step 104 , the fifth step 105 and the sixth step 106 can successively or partially or completely simultaneously for all sound generators 46 . 56 be executed. The fourth step 104 , the fifth step 105 and the sixth step 106 may be performed simultaneously for each of a plurality of sound generators, if a corresponding plurality of microphones or other means for detecting sound pressure and / or phase of sound are provided. To perform the fourth step 104 , the fifth step 105 and the sixth step 106 becomes the rotor disk 10 with a purely translatory or with a helical movement of the platen 90 removed the microphone 60 opposite the sound generator 46 . 56 can be arranged. Alternatively, the sound generator to be calibrated 46 . 56 for example, on a rail radially outward to a point outside the circumference of the rotor disk 10 method.

At a seventh step 107 and an eighth step 108 become the rotor blades 14 . 15 the rotor disk 10 by means of the sound generator 46 . 56 excited with the same or different predetermined phase relationships to the reference signal. In particular, a first rotor blade 14 with a first, at the second step 102 defined phase relationship to the reference signal and a second rotor blade 15 with a second, at the second step 102 defined phase relationship to the reference signal excited. Particularly realistic results are obtained when all rotor blades 14 . 15 be excited simultaneously with each predetermined phase relationships to the reference signal.

At a ninth step 109 becomes a resulting vibration of the rotor disk 10 detected, for example by means of a scanning laser vibrometer 70 , The vibration of the rotor disk is detected in temporal relation to the reference signal. This temporal reference is in particular that measured values are acquired at defined points in time, which have a fixed reference to the reference signal except for whole multiples of 2π.

The above based on the 3 described steps can be repeated in succession for a plurality of different frequencies. The calibration in the fourth step 104 , fifth step 105 and sixth step 106 can be like in 3 presented before the seventh step 107 , the eighth step 108 and the ninth step 109 and / or after these are executed.

The The present invention has been predominantly based on a rotor disk and the detection of their vibration behavior. she is but also on a stator disk, in particular an integrally bladed Stator disk, and the detection of their vibration behavior applicable.

The present invention is implementable as a method or computer program with program code for carrying out or controlling such a method when the computer program runs on a computer or a processor. Furthermore, the invention is as a computer program product with on a machine-readable carrier (for example, a ROM, PROM, EPROM, EEPROM or Flash memory, a CD-ROM, DVD, HD-DVD, Blue-Ray DVD , Floppy disk or hard disk) or in the form of firmware chertem program code for performing any of said methods when the computer program product runs on a computer, computer or processor implementable. Further, the present invention may be used as a digital storage medium (for example, ROM, PROM, EPROM, EEPROM or flash memory, CD-ROM, DVD, HD-DVD, Blu-Ray DVD, floppy or hard disk) with electronically readable control signals which may interact with a programmable computer or processor system to perform any of the described methods.

Further For example, the present invention can be implemented as a controller. wherein the controller is adapted to one of the described methods or the controller is a computer program, includes a computer program product or a digital storage medium, as described in the previous paragraph.

10

rotor disc

14

first rotor blade

15

second rotor blade

20

contraption for detecting a vibration behavior

30

Reference signal means

40

first exciter

42

delay means the first excitation device

44

amplifier the first excitation device

46

sound generator the first excitation device

50

second exciter

52

delay means the second excitation device

54

amplifier the second excitation device

56

sound generator the second excitation device

60

microphone

70

-scanning Laser vibrometer

71

first measuring point of the scanning laser vibrometer 70

72

second measuring point of the scanning laser vibrometer 70

78

laser beam

80

control

82

processor

84

Storage

90

platen

92

bracket

101

first step

102

second step

103

third step

104

fourth step

105

fifth step

106

sixth step

107

seventh step

108

eight step

109

ninth step

QUOTES INCLUDE IN THE DESCRIPTION

This list The documents listed by the applicant have been automated generated and is solely for better information recorded by the reader. The list is not part of the German Patent or utility model application. The DPMA takes over no liability for any errors or omissions.

Cited patent literature

• WO 2000/003197 [0006]
• - DE 69934474 T2 [0006]

Cited non-patent literature

• - "Traveling-wave excitation and optical measurement techniques for now-contacting investigation of bladed disk dynamics" by JA Judge et al. [0005]

Claims (17)

Method for detecting a vibration behavior of an integrally bladed stator or rotor disk ( 10 ), with the following steps: Define ( 102 ) a first phase relationship and a second phase relationship; Stimulate ( 107 ) a first blade ( 14 ) of the stator or rotor disk ( 10 ) having the first predetermined phase relationship with a reference signal; Stimulate ( 108 ) a second blade ( 15 ) of the stator or rotor disk ( 10 ) having the second predetermined phase relationship with the reference signal; To capture ( 109 ) of a vibration of the stator or rotor disk ( 10 ) in temporal relation to the reference signal. Method according to the preceding claim, in which the oscillation at a plurality of predetermined points ( 71 . 72 ) is detected. Method according to one of the preceding claims, where the vibration is detected by laser vibrometry. Method according to the preceding claim, in which the vibration is measured by a scanning laser vibrometer ( 70 ) is detected. Method according to one of the preceding claims, in which the blades ( 14 . 15 ) by sound generators ( 46 . 56 ) are stimulated with the blades ( 14 . 15 ) are coupled via air or another fluid. Method according to the preceding claim, further comprising the steps of: detecting ( 105 ) of the sound generator ( 46 . 56 ) generated sound; Calibrate ( 106 ) at least either the sound pressure or the phase of the sound generator ( 46 . 56 ) generated sound. Method according to claim 5 or 6, wherein a plurality of different frequencies of the reference signal are successively set, at each frequency the steps of defining ( 102 ) of phase relationships, the excitation ( 107 . 108 ) of blades ( 15 ) and recording ( 109 ) of a vibration, and at each frequency at least either before or after the steps of exciting ( 107 . 108 ) of blades ( 15 ) for each sound generator ( 46 . 56 ) at least either the sound pressure or the phase of the sound generator ( 15 ) is calibrated. Computer program with program code for carrying out or controlling a method according to one of the preceding claims, when the computer program is stored on a computer or a processor ( 82 ) expires. Contraption ( 20 ) for detecting a vibration behavior of an integrally bladed stator or rotor disk ( 10 ), comprising: a reference signal device ( 30 ) for receiving or generating a reference signal; a first excitation device ( 40 ) for exciting a first blade ( 14 ) of the stator or rotor disk ( 10 ) having a first phase relationship with the reference signal; a second excitation device ( 50 ) for exciting a second blade ( 15 ) of the stator or rotor disk ( 10 ) having a second phase relationship with the reference signal; a detection device ( 70 ) for detecting a vibration of the stator or rotor disk ( 10 ) in temporal relation to the reference signal. Contraption ( 20 ) according to the preceding claim, in which the detection device ( 70 ) for detecting the vibration at a plurality of predetermined points ( 71 . 72 ) is trained. Contraption ( 20 ) according to claim 8 or 9, wherein the detection means comprises a scanning laser vibrometer ( 70 ). Contraption ( 20 ) according to one of Claims 9 to 11, in which each exciter device ( 40 . 50 ) a sound generator ( 46 . 56 ), which is designed to be cooled by air or another fluid with a blade ( 14 . 15 ) to be coupled. Contraption ( 20 ) according to the preceding claim, further comprising a microphone ( 60 ) for detecting sound emitted by a sound generator ( 46 . 56 ) an excitation device ( 40 . 50 ) is produced; a calibration device ( 80 ), with the microphone ( 60 ) and an exciter means for calibrating at least one of the sound pressure and the phase of the sound generated by a sound generator. Contraption ( 20 ) according to the preceding claim, wherein the calibration device ( 80 ) is further configured to provide calibration factors for each excitation device ( 40 . 50 ) and for several frequencies to determine and store. Contraption ( 20 ) according to any one of claims 12 to 14, wherein the device ( 20 ) is adapted to successively set a plurality of different frequencies of the reference signal and at each frequency at least either before or after the excitation of the blades ( 14 . 15 ) for each excitation device ( 40 . 50 ) At least either the sound pressure or the phase of the excitation tion ( 40 . 50 ) to calibrate generated sound. Contraption ( 20 ) according to one of claims 9 to 15, further comprising a controller, which is designed for controlling or carrying out a method according to one of claims 1 to 7. Contraption ( 20 ) according to one of claims 9 to 16, wherein the device ( 20 ) is modular in order to adapt the device ( 20 ) on diameter and number of blades ( 14 . 15 ) different discs ( 10 ).