CN108020420A - A kind of measuring method of aero-engine rotation shaft clearance - Google Patents

A kind of measuring method of aero-engine rotation shaft clearance Download PDF

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Publication number
CN108020420A
CN108020420A CN201711247424.8A CN201711247424A CN108020420A CN 108020420 A CN108020420 A CN 108020420A CN 201711247424 A CN201711247424 A CN 201711247424A CN 108020420 A CN108020420 A CN 108020420A
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CN
China
Prior art keywords
lid
locking nut
capacitance
aero
obturaging
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
CN201711247424.8A
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Chinese (zh)
Inventor
张荫鳌
田金光
阴松凯
吴颖
赵宇
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
AECC Shenyang Liming Aero Engine Co Ltd
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AECC Shenyang Liming Aero Engine Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
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Publication date
Application filed by AECC Shenyang Liming Aero Engine Co Ltd filed Critical AECC Shenyang Liming Aero Engine Co Ltd
Priority to CN201711247424.8A priority Critical patent/CN108020420A/en
Publication of CN108020420A publication Critical patent/CN108020420A/en
Pending legal-status Critical Current

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    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01M—TESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR
    • G01M15/00—Testing of engines

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  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Measurement Of Length, Angles, Or The Like Using Electric Or Magnetic Means (AREA)

Abstract

The present invention provides a kind of measuring method of aero-engine rotation shaft clearance, is related to Aeroengine Test Technology field.A kind of measuring method of aero-engine rotation shaft clearance, first three capacitance sensors of installation are covered in obturaging for densification device, and pass through the relation between capacitance and voltage, obtain the voltage at each measuring point, then gap width between each capacitance sensor and locking nut is obtained using the magnitude of voltage of each measuring point, the gap obturaged at each measuring point between lid and locking nut is calculated finally by the gap width between each capacitance sensor and locking nut.The measuring method of aero-engine rotation shaft clearance provided by the invention, without being demarcated to capacitance sensor, it can obtain reliable test data, solves the problem that capacitance sensor demarcates difficulty in rotation axis clearance measurement, the problem of eliminating the complex work of real-time calibration in calibration in advance or experiment and its large error brought, has ensured the use reliability of test data.

Description

A kind of measuring method of aero-engine rotation shaft clearance
Technical field
The present invention relates to Aeroengine Test Technology field, more particularly to a kind of survey of aero-engine rotation shaft clearance Amount method.
Background technology
If certain fulcrum graphite seal device of aero-engine as shown in Figure 1, break down in the air, will directly affect The use reliability of engine.To search the failure mechanism of fulcrum graphite seal failure of apparatus, it is necessary to on-line measurement fulcrum graphite The gap situation of change of labyrinth assembly trouble location.
Since the point position of fulcrum graphite seal component is narrow and small (highly not in engine interior, sensor installation space Sufficient 10mm), the miniature gap sensor for belonging to hard-core technology product can only be used to measure, and require to work in engine Carry out clearance measurement under state, and the working media of measuring point is the mixed gas (mist of oil) of air and lubricating oil, oil mist concentration Change at any time with the state of engine, 160 DEG C of temperature upper limit, therefore small electrical as shown in Figure 2 is selected in actually measuring Hold sensor as clearance measurement tool.
Capacitance sensor basic test principle is the capacitance formed using the measurement plane of sensor and interplanar to be measured Functional relation between distance determines measurement gap value.
In actual measurement, an electrode of plane-parallel capacitor is may be considered installed in the probe that covers is obturaged, and is locked Tight nut is another electrode of capacitor.The capacitance measured is electrode two-plate physical dimension, distance, the letter of medium (material) Number.Shown in the capacitance of measurement and the relation equation below in gap：
D=ErE0A/C
Wherein：D is electrode gap, ErFor the relative dielectric constant of electric contrasted between solid dielectric, E0For the dielectric constant in vacuum, A is Electrode area, C are measurement capacitance.
Under engine work state, obturage the oil mist concentration between lid and locking nut and changing at any time, and temperature Degree and pressure are also parameter, along with the limitation of measurement space so that the relative dielectric constant E of mediumrIt is difficult to measure in real time, its Prior calibration process is also extremely difficult.Therefore during carrying out clearance measurement using capacitance gap sensor, capacitance sensor Calibration becomes technical barrier.
The content of the invention
The defects of for the prior art, the present invention provide a kind of measuring method of aero-engine rotation shaft clearance, realize The gap at the fulcrum graphite seal plant failure position of aero-engine is measured.
A kind of measuring method of aero-engine rotation shaft clearance, comprises the following steps：
Step 1, according to size of capacitive sensors, obturage that to cover end processing logical in the fulcrum densification device of aero-engine Hole；Capacitance sensor with installation spacing ring is placed in the through hole from the side of covering is obturaged, by the way of spot welding sheet metal Capacitance sensor is fixed on to obturage and is covered；Reuse both sides of the same procedure on lid horizontal direction is obturaged and arrange two capacitances Sensor, two capacitance sensors and the central angle for obturaging the capacitance sensor for covering end are 90 degree；
Step 2, three capacitance sensors of measurement are obturaging the retraction value h of lid end face respectively1、h2And h3, and fulcrum obturages The diameter D of the locking nut of deviceL, obturage the horizontal inside diameter D of lidsWith the perpendicular diameter D for obturaging lidc, and ensure that each retraction value is equal More than or equal to 0.2mm, less than 0.3mm；
Step 3, according to the relation between capacitance and voltage, the capacitance change measured by each measuring point obtains each measuring point Output voltage values V1、V2And V3；In synchronization, the output voltage values V of each measuring point1、V2And V3Passed with each capacitance actually measured Gap width c between sensor and locking nut1、c2And c3For linear relationship, shown in following three formula：
c1/(c1+c2)=V1/(V1+V2)
c2/(c1+c2)=V2/(V1+V2)
c3/(c1+c2)=V3/(V1+V2)
Wherein, c1+c2=Js+h1+h2, Js=Ds-DLTo obturage the horizontal diameter gap between lid and locking nut；
Make b=Js+h1+h2, the distance further obtained between each capacitance sensor and locking nut is：
c1=bV1/(V1+V2)
c2=bV2/(V1+V2)
c3=bV3/(V1+V2)
At a certain moment, the gap jx between lid and locking nut is obturaged at each measuring point1、jx2And jx3With each capacitance sensor Gap width c between locking nut1、c2And c3Meet relationship below：
jx1=c1-h1=bV1/(V1+V2)-h1,
jx2=c2-h2=bV2/(V1+V2)-h2,
jx3=c3-h3=bV3/(V1+V2)-h3。
Step 4, obtain and obturage the angle of instantaneous circumference minimum clearance and its present position between lid and locking nut；
The center of circle for obturaging lid is the coordinate origin o of basic coordinate system, and locking nut axle center coordinate is o ' (ox,oy), then lock Nut axle center coordinate meets following two relational expressions：
ox=(jx1-jx2)/2
oy=Jc/2-jx3
Wherein, Jc=Dc-DLTo obturage the perpendicular diameter gap between lid and locking nut；
And then show that obturaging instantaneous circumference minimum clearance between lid and locking nut is：
The angle for obturaging instantaneous circumference minimum clearance present position between lid and locking nut is：
WZmin=tan-1(oy/ox)。
As shown from the above technical solution, the beneficial effects of the present invention are：A kind of aero-engine rotation provided by the invention The measuring method in shaft gap, passes through the specific arrangements of three capacitance sensor installation sites and the processing to measurement data, nothing Capacitance sensor need to be demarcated, you can obtain reliable test data, solve capacitance sensor and surveyed in rotation shaft clearance The problem of difficulty is demarcated in amount, eliminates the complex work of real-time calibration and its large error brought in calibration in advance or experiment The problem of, ensure the use reliability of test data.
Brief description of the drawings
Fig. 1 is the structure diagram of certain fulcrum graphite seal device of certain aero-engine；
Fig. 2 is the structure diagram of certain small-sized capacitance sensor as clearance measurement tool；
Fig. 3 is the flow chart for the measuring method that a kind of aero-engine provided in an embodiment of the present invention rotates shaft clearance；
Fig. 4 is obturaging the schematic view of the mounting position covered for three capacitance sensors provided in this embodiment；
Fig. 5 is the part-structure schematic diagram of the densification device of capacitor sensor provided in this embodiment；
Installation site scale diagrams of Fig. 6 capacitance sensors provided in this embodiment in densification device；
Fig. 7 is schematic diagram of the gap each parameter provided by the embodiment obturaged between lid and locking nut in coordinate system.
In figure：1st, lid is obturaged；2nd, locking nut；3rd, the capacitance sensor for covering end is obturaged；4th, lid horizontal direction two is obturaged The capacitance sensor of side.
Embodiment
With reference to the accompanying drawings and examples, the embodiment of the present invention is described in further detail.Implement below Example is used to illustrate the present invention, but is not limited to the scope of the present invention.
The present embodiment is by taking certain fulcrum graphite seal device of certain aero-engine as an example, using the method for the present invention to obturaging lid Gap between locking nut measures.
A kind of measuring method of aero-engine rotation shaft clearance, as shown in figure 3, comprising the following steps：
Step 1, according to size of capacitive sensors, obturage the processing of 1 upper end of lid in the fulcrum densification device of aero-engine Through hole；Capacitance sensor 3 with installation spacing ring is covered end and is placed in the through hole from obturaging, using the side of spot welding sheet metal Capacitance sensor 3 is fixed on to obturage and covered by formula；Reuse both sides of the same procedure on 1 horizontal direction of lid is obturaged and arrange two Capacitance sensor 4, two capacitance sensors 4 and the central angle for obturaging the capacitance sensor 3 for covering end are 90 degree；
In the present embodiment, three capacitance sensors cover end obturaging the installation site that covers 1 as shown in figure 4, obturaging Installation site of the capacitance sensor 3 in densification device is as shown in Figure 5.Three capacitance sensors of installation are used such as Fig. 2 institutes The capacitance sensor CP200 shown, the size of capacitive sensors are 8 × 8.5mm, measurement range 0.2-2mm, and Measurement Resolution is 5 μm, operating temperature ≯ 200 DEG C.
Step 2, three capacitance sensors of measurement are obturaging the retraction value h of lid end face respectively1、h2And h3And fulcrum is obturaged The diameter D of the locking nut 2 of deviceL, obturage the horizontal inside diameter D of lidsWith the perpendicular diameter D for obturaging lidc, and ensure each retraction value h1、h2And h3It is all higher than being equal to 0.2mm, less than 0.3mm；
Step 3, according to the relation between capacitance and voltage, the capacitance change measured by each measuring point obtains each measuring point Output voltage values V1、V2And V3；The a certain moment obturages lid 1 and the mist of oil in the gap of locking nut 2 to engine in the operating condition Concentration is theoretically uniform in each measuring point, and the environmental parameter such as temperature, pressure is also basically identical, herein under the premise of, a certain moment Relative dielectric constant Er in each measuring point should be consistent；Therefore, in synchronization, the output voltage values V of each measuring point1、V2With V3With the gap width c between each capacitance sensor and locking nut 2 that actually measure1、c2And c3It is public for linear relationship, following three Shown in formula：
c1/(c1+c2)=V1/(V1+V2)
c2/(c1+c2)=V2/(V1+V2)
c3/(c1+c2)=V3/(V1+V2)
Wherein, c1+c2=Js+h1+h2, Js=Ds-DLTo obturage the horizontal diameter gap between lid 1 and locking nut 2；
Make b=Js+h1+h2, the distance further obtained between each capacitance sensor and locking nut 2 is：
c1=bV1/(V1+V2)
c2=bV2/(V1+V2)
c3=bV3/(V1+V2)
Installation site size of the capacitance sensor 3 for covering end in densification device is obturaged as shown in fig. 6, a certain moment, The gap jx between lid 1 and locking nut 2 is obturaged at each measuring point1、jx2And jx3Between each capacitance sensor and locking nut 1 Gap c1、c2And c3Meet relationship below：
jx1=c1-h1=bV1/(V1+V2)-h1,
jx2=c2-h2=bV2/(V1+V2)-h2,
jx3=c3-h3=bV3/(V1+V2)-h3。
Step 4, obtain and obturage the angle of instantaneous circumference minimum clearance and its present position between lid 1 and locking nut 2, such as Shown in Fig. 7；
The center of circle for obturaging lid 1 is the coordinate origin o of basic coordinate system, and 2 axle center coordinate of locking nut is o ' (ox,oy), then lock Tight 2 axle center coordinate of nut meets following two relational expressions：
ox=(jx1-jx2)/2
oy=Jc/2-jx3
Wherein, Jc=Dc-DLTo obturage the perpendicular diameter gap between lid 1 and locking nut 2；
And then show that obturaging instantaneous circumference minimum clearance between lid 1 and locking nut 2 is：
The angle for obturaging instantaneous circumference minimum clearance present position between lid 1 and locking nut 2 is：
WZmin=tan-1(oy/ox)。
In the present embodiment, capacitive sensor signal is converted to by digital signal using HBM MX840A data collecting systems, Sample frequency 1200Hz/CH, test data is stored using HBM CX22W data loggers, and test data is carried out by computer Post-processing.
In the present embodiment, three capacitance sensors measuring are respectively h obturaging the retraction value of 1 end face of lid1=0.2755, h2=0.2234, h3=0.2469.A diameter of D of the locking nut 2 measuredL=211.3275mm, obturages the horizontal inside diameter of lid 1 For Ds=210.9834mm, the perpendicular diameter for obturaging lid 1 are Dc=211.0613mm.
Test the instantaneous circumference minimum clearance jx of overall processminFor scope between 0.18-0.83mm, revolution is lower, instantaneous circumference Gap width is smaller, as revolution rise gap becomes larger.
Instantaneous minimum gap location WZminIt is distributed in whole circumference, comes across near 6 o'clock of 11 o'clock of top and bottom Occupy the majority, the position of small gap is in bottom.
Finally it should be noted that：The above embodiments are merely illustrative of the technical solutions of the present invention, rather than its limitations；Although The present invention is described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that：It still may be used To modify to the technical solution described in previous embodiment, either which part or all technical characteristic are equal Replace；And these modifications or replacement, the essence of appropriate technical solution is departed from the model that the claims in the present invention are limited Enclose.

Claims (5)

  1. A kind of 1. measuring method of aero-engine rotation shaft clearance, it is characterised in that：Comprise the following steps：
    Step 1, according to size of capacitive sensors, cover end processing through hole in the obturaging for fulcrum densification device of aero-engine, Capacitance sensor with installation spacing ring is placed in through hole from the side of covering is obturaged, and by capacitance by the way of spot welding sheet metal Sensor is fixed on to obturage and covers；Reuse both sides of the same procedure on lid horizontal direction is obturaged and arrange two capacitance sensings Device, two capacitance sensors and the central angle for obturaging the capacitance sensor for covering end are 90 degree；
    Step 2, three capacitance sensors of measurement are obturaging the retraction value h of lid end face respectively1、h2And h3, and fulcrum densification device Locking nut diameter DL, obturage the horizontal inside diameter D of lidsWith the perpendicular diameter D for obturaging lidc；
    Step 3, obtain each measuring point of a certain moment and obturage gap width between lid and locking nut；
    Step 4, obtain and obturage the angle of instantaneous circumference minimum clearance and its present position between lid and locking nut.
  2. A kind of 2. measuring method of aero-engine rotation shaft clearance according to claim 1, it is characterised in that：Step 1 A diameter of 8mm of the through hole.
  3. A kind of 3. measuring method of aero-engine rotation shaft clearance according to claim 1, it is characterised in that：Step 2 Three capacitance sensors are obturaging the retraction value h of lid end face1、h2And h3It is all higher than being equal to 0.2mm, less than 0.3mm.
  4. A kind of 4. measuring method of aero-engine rotation shaft clearance according to claim 1, it is characterised in that：The step Rapid 3 specific method is：
    According to the relation between capacitance and voltage, the capacitance change measured by each measuring point obtains the output voltage values of each measuring point V1、V2And V3；Synchronization, the output voltage values V of each measuring point1、V2And V3With each capacitance sensor and locking screw actually measured Gap width c between mother1、c2And c3For linear relationship, shown in following three formula：
    c1/(c1+c2)=V1/(V1+V2)
    c2/(c1+c2)=V2/(V1+V2)
    c3/(c1+c2)=V3/(V1+V2)
    Wherein, c1+c2=Js+h1+h2, Js=Ds-DLTo obturage the horizontal diameter gap between lid and locking nut；
    Make b=Js+h1+h2, the distance further obtained between each capacitance sensor and locking nut is：
    c1=bV1/(V1+V2)
    c2=bV2/(V1+V2)
    c3=bV3/(V1+V2)
    At a certain moment, the gap jx between lid and locking nut is obturaged at each measuring point1、jx2And jx3With each capacitance sensor and lock Gap width c between tight nut1、c2And c3Meet relationship below：
    jx1=c1-h1=bV1/(V1+V2)-h1,
    jx2=c2-h2=bV2/(V1+V2)-h2,
    jx3=c3-h3=bV3/(V1+V2)-h3。
  5. A kind of 5. measuring method of aero-engine rotation shaft clearance according to claim 4, it is characterised in that：The step Rapid 4 specific method is：
    The center of circle for obturaging lid is the coordinate origin o of basic coordinate system, and locking nut axle center coordinate is o ' (ox,oy), then locking nut Axle center coordinate meets following two relational expressions：
    ox=(jx1-jx2)/2
    oy=Jc/2-jx3
    Wherein, Jc=Dc-DLTo obturage the perpendicular diameter gap between lid and locking nut；
    And then show that obturaging instantaneous circumference minimum clearance between lid and locking nut is：
    <mrow> <msub> <mi>jx</mi> <mrow> <mi>m</mi> <mi>i</mi> <mi>n</mi> </mrow> </msub> <mo>=</mo> <mrow> <mo>(</mo> <msub> <mi>J</mi> <mi>s</mi> </msub> <mo>+</mo> <msub> <mi>J</mi> <mi>c</mi> </msub> <mo>)</mo> </mrow> <mo>/</mo> <mn>4</mn> <mo>-</mo> <msqrt> <mrow> <msup> <msub> <mi>o</mi> <mi>x</mi> </msub> <mn>2</mn> </msup> <mo>+</mo> <msup> <msub> <mi>o</mi> <mi>y</mi> </msub> <mn>2</mn> </msup> </mrow> </msqrt> </mrow>
    The angle for obturaging instantaneous circumference minimum clearance present position between lid and locking nut is：
    WZmin=tan-1(oy/ox)。
CN201711247424.8A 2017-12-01 2017-12-01 A kind of measuring method of aero-engine rotation shaft clearance Pending CN108020420A (en)

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CN201711247424.8A CN108020420A (en) 2017-12-01 2017-12-01 A kind of measuring method of aero-engine rotation shaft clearance

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Application Number Priority Date Filing Date Title
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Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH05172707A (en) * 1991-12-25 1993-07-09 Toshiba Corp State monitor
CN101046367A (en) * 2006-03-30 2007-10-03 通用电气公司 Multi tip clearance measurement system and method of operation
CN101329167A (en) * 2008-07-11 2008-12-24 西安交通大学 Dynamic measurement method of slide bearing lubricating film and fiber optic sensor for measurement
RU2379626C1 (en) * 2008-06-16 2010-01-20 Институт проблем управления сложными системами Российской академии наук Method for assessment of stator deformation and parametres of run-out of gas turbine engine
CN104154853A (en) * 2014-08-26 2014-11-19 上海瑞视仪表电子有限公司 Method for measuring wind driven generator air gap through eddy current sensors
CN105987657A (en) * 2015-02-12 2016-10-05 珠海格力节能环保制冷技术研究中心有限公司 Current vortex sensor used for rotating shaft and rotating shaft apparatus
CN106595463A (en) * 2016-11-22 2017-04-26 沈阳黎明航空发动机(集团)有限责任公司 Static assembling gap measuring device and method for bearing of aeroengine

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH05172707A (en) * 1991-12-25 1993-07-09 Toshiba Corp State monitor
CN101046367A (en) * 2006-03-30 2007-10-03 通用电气公司 Multi tip clearance measurement system and method of operation
RU2379626C1 (en) * 2008-06-16 2010-01-20 Институт проблем управления сложными системами Российской академии наук Method for assessment of stator deformation and parametres of run-out of gas turbine engine
CN101329167A (en) * 2008-07-11 2008-12-24 西安交通大学 Dynamic measurement method of slide bearing lubricating film and fiber optic sensor for measurement
CN104154853A (en) * 2014-08-26 2014-11-19 上海瑞视仪表电子有限公司 Method for measuring wind driven generator air gap through eddy current sensors
CN105987657A (en) * 2015-02-12 2016-10-05 珠海格力节能环保制冷技术研究中心有限公司 Current vortex sensor used for rotating shaft and rotating shaft apparatus
CN106595463A (en) * 2016-11-22 2017-04-26 沈阳黎明航空发动机(集团)有限责任公司 Static assembling gap measuring device and method for bearing of aeroengine

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Application publication date: 20180511