CN109374166B - Distributed measuring device and method - Google Patents
Distributed measuring device and method Download PDFInfo
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- CN109374166B CN109374166B CN201811503049.3A CN201811503049A CN109374166B CN 109374166 B CN109374166 B CN 109374166B CN 201811503049 A CN201811503049 A CN 201811503049A CN 109374166 B CN109374166 B CN 109374166B
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- 238000000034 method Methods 0.000 title claims description 17
- 239000013598 vector Substances 0.000 claims abstract description 43
- 238000005259 measurement Methods 0.000 claims abstract description 31
- 239000013307 optical fiber Substances 0.000 claims description 47
- 239000011159 matrix material Substances 0.000 claims description 13
- 230000003068 static effect Effects 0.000 claims description 3
- 238000004364 calculation method Methods 0.000 claims description 2
- 239000007921 spray Substances 0.000 claims 2
- 230000008878 coupling Effects 0.000 description 3
- 238000010168 coupling process Methods 0.000 description 3
- 238000005859 coupling reaction Methods 0.000 description 3
- 238000005516 engineering process Methods 0.000 description 3
- 230000005484 gravity Effects 0.000 description 3
- 238000011068 loading method Methods 0.000 description 3
- 238000005096 rolling process Methods 0.000 description 3
- 238000010276 construction Methods 0.000 description 2
- RZVHIXYEVGDQDX-UHFFFAOYSA-N 9,10-anthraquinone Chemical compound C1=CC=C2C(=O)C3=CC=CC=C3C(=O)C2=C1 RZVHIXYEVGDQDX-UHFFFAOYSA-N 0.000 description 1
- 230000000712 assembly Effects 0.000 description 1
- 238000000429 assembly Methods 0.000 description 1
- 230000005540 biological transmission Effects 0.000 description 1
- 230000008859 change Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 238000009434 installation Methods 0.000 description 1
- 238000003754 machining Methods 0.000 description 1
- 230000008569 process Effects 0.000 description 1
Images
Classifications
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01L—MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
- G01L1/00—Measuring force or stress, in general
- G01L1/24—Measuring force or stress, in general by measuring variations of optical properties of material when it is stressed, e.g. by photoelastic stress analysis using infrared, visible light, ultraviolet
- G01L1/242—Measuring force or stress, in general by measuring variations of optical properties of material when it is stressed, e.g. by photoelastic stress analysis using infrared, visible light, ultraviolet the material being an optical fibre
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01L—MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
- G01L5/00—Apparatus for, or methods of, measuring force, work, mechanical power, or torque, specially adapted for specific purposes
- G01L5/0028—Force sensors associated with force applying means
- G01L5/0038—Force sensors associated with force applying means applying a pushing force
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01L—MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
- G01L5/00—Apparatus for, or methods of, measuring force, work, mechanical power, or torque, specially adapted for specific purposes
- G01L5/16—Apparatus for, or methods of, measuring force, work, mechanical power, or torque, specially adapted for specific purposes for measuring several components of force
- G01L5/166—Apparatus for, or methods of, measuring force, work, mechanical power, or torque, specially adapted for specific purposes for measuring several components of force using photoelectric means
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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
Abstract
Disclosed is a distributed measurement apparatus for measuring the vector thrust of a combined engine comprising two or more aeroengines, the distributed measurement apparatus comprising a support assembly, a mounting assembly and a measurement assembly, wherein: mounting and fixing the combined engine to the support assembly through the mounting assembly; the measuring assembly is arranged on the mounting assembly, collects thrust generated by two or more aircraft engines during operation, and obtains vector thrust of the combined engine by using the collected thrust.
Description
Technical Field
The invention belongs to the technical field of aero-engines, and particularly relates to a distributed measuring device and method for measuring vector thrust of a combined engine.
Background
Thrust is the primary parameter for assessing aircraft and engine performance. With the improvement of technical indexes of the fighter, the thrust vector technology becomes one of the landmark technologies of the fourth generation fighter, and the thrust vector technology endows the aircraft with the characteristics of over-stall and over-maneuverability, high agility, short-distance take-off and landing performance, low detectability and supersonic cruise capability, thereby greatly improving the operational efficiency and the survivability of the fighter. In the design of an aircraft flight control system provided with a vectoring nozzle, diversified control of an engine and an aircraft is required to be carried out by calculating the thrust, so that how to effectively and directly measure the thrust of the engine is a common technical problem.
At present, the most extensive vector thrust measurement mode is a vector thrust test bed, and the vector thrust test bed has the main functions of accurately measuring the vector thrust generated in an engine test, acquiring each directional component of the vector force through a thrust rack, and evaluating the acting point, the acting direction and the magnitude of the vector force. The principle is as follows: by using rigid body balance principle, several constraints are properly arranged to limit 6 degrees of freedom (3 degrees of freedom of movement and 3 degrees of freedom of rotation) of the engine, so that the engine is in a statically or statically indeterminate balance state, and the magnitude and vector angle of the thrust component are measured.
The vector thrust test bed is used as a main device for evaluating the vector thrust engine, has the characteristics of various layout forms of the force measuring assembly, complex thrust transmission route and the like, and the technical state of the test bed is important for evaluating the performance of the vector thrust engine. However, the vector thrust test bed has insufficient universality, is usually designed for a certain type of engine, and has long construction, reconstruction and debugging periods and high economic cost. For a combined power engine, the thrust measurement is carried out by adopting a conventional vector thrust measurement rack, so that the difficulty is higher. Due to factors such as machining errors and installation errors of the force measuring assembly, deformation of the rack under stress and the like, the force measuring assembly in a non-thrust direction generates coupling output errors in the thrust measuring process, and the vector force measuring precision is seriously influenced.
Disclosure of Invention
Object of the Invention
It is an object of the present invention to provide a distributed vector thrust measurement apparatus and method for an aircraft engine that addresses at least one of the problems of the above background art or at least provides a useful commercial choice.
Technical scheme
The above object is achieved by a distributed measuring device of the present invention for measuring the vector thrust of a combined engine comprising two or more aeroengines, comprising a support assembly, a mounting assembly and a measuring assembly, wherein: mounting and fixing the combined engine to the support assembly through the mounting assembly; the measuring assembly is arranged on the mounting assembly, collects thrust generated by two or more aircraft engines during operation, and obtains vector thrust of the combined engine by using the collected thrust.
In the distributed measurement device, the vector thrust of the combined engine is obtained by using the collected thrust in combination with the spatial arrangement of the measurement components.
In the above-described distributed measuring apparatus, the spatial arrangement of the measuring components includes spatial positions and/or directional angles of the measuring components.
In the distributed measuring device, the measuring assembly comprises an optical fiber force measuring unit, the optical fiber force measuring unit measures and outputs the stress of the mounting assembly, and the vector thrust of the combined engine is obtained through the stress of the mounting assembly.
There is also provided a method for measuring vector thrust for a combined engine comprising two or more aero-engines, the method employing a distributed measurement apparatus comprising a support assembly, a mounting assembly and a measurement assembly, wherein the method comprises: mounting and fixing the combined engine to the support assembly through the mounting assembly; disposing a measurement assembly on the mounting assembly; collecting thrust generated by two or more aircraft engines in operation through a measuring assembly; and obtains the vector thrust of the combined engine using the collected thrust.
In the method of the invention, the vector thrust of the combined engine is obtained using the thrust collected in combination with the spatial arrangement of the measurement assemblies.
In the method of the invention, the spatial arrangement of the measurement assembly comprises the spatial position and/or the orientation angle of the measurement assembly.
Advantageous effects
The invention relates to a distributed vector thrust measuring device and method for an aircraft engine, which are used for measuring the vector thrust of the engine by arranging optical fiber force measuring units on main and auxiliary mounting joint structures of the engine and a pneumatic vector nozzle. The problem of take pneumatic thrust vectoring nozzle's of binary unilateral inflation combination power engine can't adopt conventional vector thrust rack to carry out vector thrust measurement is solved, simultaneously to the problem that conventional vector thrust test bed commonality is not enough, construction debugging cycle is long, economic cost is high, provide new thinking.
Drawings
FIG. 1 is a schematic diagram of a distributed measurement apparatus of the present invention;
FIG. 2 illustrates a first primary mounting section of the distributed measuring apparatus of the present invention;
FIG. 2a shows a cross-sectional view taken along line A-A in FIG. 2;
FIG. 3 illustrates a first auxiliary mounting section of the distributed measuring apparatus of the present invention;
fig. 3a shows a cross-sectional view taken along line B-B in fig. 3.
Detailed Description
In fig. 1, an upper engine 1, a combined nozzle 5 and a lower engine 9 form a combined engine, and the combined nozzle 5 generates vector thrust consisting of an axial force Fx, a vertical force Fy, a pitching moment Mz and a rolling moment Mx. The upper engine 1 is fixed on the front mounting frame 2 through a first main mounting joint 3 and a first auxiliary mounting joint 4; the lower engine 9 is fixed on the front mounting frame 2 through a third main mounting section 8 and a third auxiliary mounting section 10; the combined nozzle 5 is fixed on the rear mounting frame 6 through a second main mounting joint 11 and a second auxiliary mounting joint 7.
Loads such as axial thrust Fx, vertical thrust Fy, gravity G, maneuvering overload and the like of the engine are transmitted to the rack by the main mounting joint and the auxiliary mounting joint. The main mounting point restrains axial thrust, vertical force and gravity of the engine and belongs to a cantilever beam structure; the auxiliary mounting point is of a pull rod structure, restrains the gravity and the vertical force of the engine, only bears the force on the pull rod, and belongs to a two-force rod structure. The first main mounting section 3, the second main mounting section 11 and the third main mounting section 8 realize measurement of a main thrust Fx and a vertical force Fy, and the first auxiliary mounting section 4, the second auxiliary mounting section 7 and the third auxiliary mounting section 10 realize measurement of a pitching moment Mz and a rolling moment Mx.
In fig. 2, a core bar 31, a mounting seat 32, an adjusting nut 33, an elastic beam 34 and a conical head 35 form a first main mounting joint 3. The mounting seat 32 is fixed on the front mounting frame 2, the core bar 31 passes through the mounting seat 32, the position of the core bar 31 is changed by the adjusting nut 33, and the conical head 35 is inserted into the ball socket on the upper engine 1 to fix the upper engine 1. An elastic beam 34 is arranged between the core rod 31 and the conical head 35, four optical fiber force measuring units are uniformly distributed on the periphery of the elastic beam, a first vertical force optical fiber force measuring unit 36 and a second vertical force optical fiber force measuring unit 39 are used for measuring vertical force Fy and are respectively positioned at the top and the bottom of the elastic beam 34, and a first axial force optical fiber force measuring unit 37 and a second axial force optical fiber force measuring unit 38 are used for measuring main thrust Fx and are respectively positioned at the front end and the rear end of the elastic beam 34.
Because the combined engine is in a severe environment and has large temperature change, in order to eliminate the influence of temperature on the elastic beam 34, the first vertical force optical fiber force measuring unit 36, the first axial force optical fiber force measuring unit 37, the second axial force optical fiber force measuring unit 38 and the second vertical force optical fiber force measuring unit 39 and improve the measurement accuracy, the first vertical force optical fiber force measuring unit 36, the first axial force optical fiber force measuring unit 37, the second axial force optical fiber force measuring unit 38 and the second vertical force optical fiber force measuring unit 39 all adopt a full-bridge wiring method, and meanwhile, a temperature compensation device is added.
The output of the first vertical force optical fiber force measuring unit 36 is R36, the output of the first axial force optical fiber force measuring unit 37 is R37, the output of the second axial force optical fiber force measuring unit 38 is R38, and the output of the second vertical force optical fiber force measuring unit 39 is R39.
Similarly, the second main mounting section 11 and the third main mounting section 8 are similar to the first main mounting section 3 in structure, and will not be described in detail here. The outputs of the four optical fiber force measuring units of the second main mounting section 11 are respectively R116, R117, R118 and R119, and the outputs of the four optical fiber force measuring units of the third main mounting section 8 are respectively R86, R87, R88 and R89.
In fig. 3, the fixing base 41, the first connecting rod 42, the force measuring rod 43, and the second connecting rod 44 form a first auxiliary mounting section. The fixing base 41 is installed on the front mounting frame 2, one end of the first connecting rod 42 is fixed on the fixing base 41, and one end of the first connecting rod is connected with the force measuring rod 43, and one end of the second connecting rod 44 is connected with the force measuring rod 43, and the other end of the second connecting rod is connected with the upper engine 1, so that the upper engine 1 is fixed. Four optical fiber force measuring units are uniformly distributed on the force measuring rod 43 in the circumferential direction, and a first tension optical fiber force measuring unit 45, a second tension optical fiber force measuring unit 46, a third tension optical fiber force measuring unit 47 and a fourth tension optical fiber force measuring unit 48 form a coupling loop for measuring pitching moment Mz and rolling moment Mx.
Similarly, in order to eliminate the influence of temperature on the force measuring rod 43, the first tension optical fiber force measuring unit 45, the second tension optical fiber force measuring unit 46, the third tension optical fiber force measuring unit 47 and the fourth tension optical fiber force measuring unit 48 and improve the measurement accuracy, the first tension optical fiber force measuring unit 45, the second tension optical fiber force measuring unit 46, the third tension optical fiber force measuring unit 47 and the fourth tension optical fiber force measuring unit 48 all adopt a full-bridge wiring method, and meanwhile, a temperature compensation device is added.
The output of the first tension optical fiber force measuring unit 45 is R45, the output of the second tension optical fiber force measuring unit 46 is R46, the output of the third tension optical fiber force measuring unit 47 is R47, and the output of the fourth tension optical fiber force measuring unit 48 is R48.
Similarly, the second auxiliary mounting node 7 and the third auxiliary mounting node 10 are similar to the first auxiliary mounting node 4 in structure and will not be described in detail here. The outputs of the four optical fiber force measuring units of the second auxiliary mounting section 7 are respectively R75, R76, R77 and R78, and the outputs of the four optical fiber force measuring units of the third auxiliary mounting section 10 are respectively R105, R106, R107 and R108.
The stress conditions of 3 groups of main mounting joints and 3 groups of auxiliary mounting joints are obtained through 48 groups of optical fiber force measuring units, and the next step of work is to calculate the resultant force of the force of each mounting joint relative to a reference point according to the spatial positions and direction angles of the main mounting joint and the auxiliary mounting joints.
The first main mounting section 3 is stressed respectively as follows:
the stress of the second main mounting section 11 is respectively:
the third main mounting section 8 is stressed respectively as follows:
the first auxiliary mounting section 4 is stressed respectively as follows:
the second auxiliary mounting section 7 is stressed respectively as follows:
the third auxiliary mounting section 10 is stressed as follows:
therefore, the vector thrust measurement result of the combined engine is as follows:
in order to realize the decoupling of the measured data, calibration is required before a test, and a decoupling matrix is obtained. And according to the selected calibration loading method and the calibration test data, performing decoupling calculation on the vector thrust measurement system by using a static decoupling algorithm for solving the generalized inverse of the matrix, and evaluating the coupling error of the system and the effectiveness of the static decoupling algorithm.
Representing a set of matrices (12-dimensional column vectors) of calibrated loading forces by F, K sets of loading data can form a 12 x K matrix F]N(ii) a By using a matrix R to represent a matrix (m-dimensional column vector) formed by measurement indications of a set of vector thrust measurement platforms, an m × K matrix R can be obtained. From the linear theoretical calibration model, the following matrix equation can be obtained:
F＝AR+E
where E represents the residual error, which conforms to the previous error assumption. Obtaining an unbiased estimate of the coefficient matrix A according to the least squares principle
It is necessary to let E equal 0, i.e.:
if the constructed matrix R is of full rank, with the rank m, the matrix R isTThe determinant of R is not equal to 0, then
There must be a unique solution. Matrix expression of calibration coefficient matrix solution for arbitrary components:
Claims (4)
1. a distributed measuring device is used for measuring the vector thrust of a combined engine, the combined engine consists of an upper engine, a combined spray pipe and a lower engine, the distributed measuring device comprises a supporting component, a mounting component and a measuring component, and the combined engine is mounted and fixed on the supporting component through the mounting component; the method is characterized in that:
the supporting assembly comprises a front mounting frame and a rear mounting frame, the mounting assembly comprises a main mounting section and an auxiliary mounting section, the main mounting section comprises a first main mounting section, a second main mounting section and a third main mounting section, and the auxiliary mounting section comprises a first auxiliary mounting section, a second auxiliary mounting section and a third auxiliary mounting section; the upper engine is fixed on the front mounting frame through a first main mounting joint and a first auxiliary mounting joint; the lower engine is fixed on the front mounting frame through a third main mounting joint and a third auxiliary mounting joint; the combined spray pipe is fixed on the rear mounting rack through a second main mounting joint and a second auxiliary mounting joint; the measuring assembly comprises an optical fiber force measuring unit;
the first main mounting joint consists of a core bar, a mounting seat, an adjusting nut, an elastic beam and a conical head; the mounting seat is fixed on the front mounting frame, the core rod penetrates through the mounting seat, the position of the core rod is changed through the adjusting nut, and the conical head is inserted into a ball socket on the upper engine to fix the upper engine; an elastic beam is arranged between the core rod and the conical head, and four optical fiber force measuring units are uniformly distributed on the elastic beam in the circumferential direction;
the first auxiliary mounting joint consists of a fixed seat, a first connecting rod, a force measuring rod and a second connecting rod, wherein the fixed seat is mounted on the front mounting frame, one end of the first connecting rod is fixed on the fixed seat, the other end of the first connecting rod is connected with the force measuring rod, one end of the second connecting rod is connected with the force measuring rod, the other end of the second connecting rod is connected with the upper engine and used for fixing the upper engine, and four optical fiber force measuring units are uniformly distributed on the force measuring rod in the circumferential direction;
the optical fiber force measuring unit adopts a full-bridge wiring method, and a temperature compensation device is added; the optical fiber force measuring unit measures and outputs the stress of the mounting assembly, and the vector thrust of the combined engine is obtained through the stress of the mounting assembly.
2. A distributed measurement apparatus as claimed in claim 1 wherein the collected thrust is used to derive the vectorial thrust of the combined engine in conjunction with the spatial arrangement of the measurement components.
3. A distributed measurement apparatus as claimed in claim 2, wherein the spatial arrangement of measurement components comprises the spatial position and orientation angle of the measurement components.
4. A method for measuring combined engine vector thrust, characterized in that it employs a distributed measuring device according to any one of claims 1 to 3, wherein the method comprises:
disposing a measurement assembly on the mounting assembly;
the thrust generated by the combined engine during operation is collected through the measuring assembly, decoupling calculation is carried out on the vector thrust measuring system by using a static decoupling algorithm for solving the generalized inverse matrix, and the vector thrust of the combined engine is obtained by using the collected thrust in combination with the spatial position and the direction angle of the measuring assembly.
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| CN109374166B true CN109374166B (en) | 2021-08-03 |
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| CN114166510B (en) * | 2021-10-20 | 2023-06-13 | 中国航发四川燃气涡轮研究院 | Transverse rigidity measuring device of force measuring assembly |
| CN114923617B (en) * | 2022-07-21 | 2022-10-25 | 中国航发四川燃气涡轮研究院 | Engine lift force measuring device |
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| CN202693314U (en) * | 2012-06-15 | 2013-01-23 | 北京中陆航星机械动力科技有限公司 | Turbojet engine test bed |
| CN106546380B (en) * | 2016-09-28 | 2019-02-15 | 中国航空规划设计研究总院有限公司 | A kind of stepless space criteria vectorial force calibrating installation |
| CN106500902B (en) * | 2016-12-03 | 2019-08-02 | 中国航空工业集团公司北京长城计量测试技术研究所 | A kind of strain-type multidimensional force sensor with from decoupling function |
| CN106595935B (en) * | 2016-12-14 | 2019-10-18 | 中国燃气涡轮研究院 | Rack can be measured from uncoupled aero-engine vectorial force |
| CN206990215U (en) * | 2017-06-26 | 2018-02-09 | 中电科芜湖钻石飞机制造有限公司 | Aircraft engine test stand frame |
| CN108168774B (en) * | 2017-12-27 | 2020-01-14 | 中国航发四川燃气涡轮研究院 | Space vector force calibration method |
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