A test method and system for aeroengine floating ring seal device

Abstract

The application discloses a test and examination method and system for an aero-engine floating ring sealing device, and relates to the technical field of aero-engines.The method comprises the following steps: performing a first round of basic tests on a floating ring test piece; performing a radial impact and friction test on the floating ring test piece that has undergone the first round of basic tests; performing a fretting wear test on the floating ring test piece that has undergone the radial impact and friction test; performing a second round of basic tests on the floating ring test piece that has undergone the fretting wear test, and checking whether the floating ring test piece passes the test and examination.The application performs the test and examination on the floating ring based on a failure mode, is more systematic and comprehensive in the test and examination on the floating ring, avoids the insufficient reliability and service life of the floating ring sealing in the service process, improves the floating ring test and examination technology, and realizes the standardization, technical generalization and application serialization of the aero-engine graphite material floating ring test and examination.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of aero-engine, and particularly relates to a test and evaluation method and system for a floating ring sealing device of an aero-engine. BACKGROUND

[0002] The floating ring seal is mainly applied to bearing cavity sealing in an aero-engine. The floating ring seal is generally composed of a floating ring, a gasket, a wave spring, a retainer and a shell. The floating ring is composed of a graphite ring and a steel ring, and is tightly attached to the inner side of the shell through the wave spring to form a secondary seal. The floating ring and the rotating sealing track have a certain gap δ. In normal operation, the floating ring and the surface of the track are separated by a rigid fluid film, which prevents the high-pressure side gas from leaking to the low-pressure side. At the same time, the end face of the sealing ring is tightly attached to the inner side of the shell under the action of the wave spring to prevent radial gas leakage. The floating ring can move with the radial runout of the high-speed rotating circumferential surface, and can eliminate hard contact friction in normal operation. Similar to the fluid dynamic bearing, the fluid in the sealing gap generates dynamic pressure buoyancy on the floating ring during operation. When the dynamic pressure buoyancy is greater than the weight of the sealing ring, the inertial force of the floating movement and the frictional force of the contact load between the sealing ring and the end face of the shell, the floating ring and the surface of the track are separated by the fluid film, and the contact friction of the solid is eliminated. Under the condition of good gap control and friction and wear control, the sliding speed of the floating ring sealing device can be more than 200 m / s. Compared with other types of main bearing cavity sealing devices, the floating ring sealing device has small friction, low friction heat, small power consumption, is suitable for high-speed and high-temperature environments, and has high reliability. In recent years, it has been widely used in engine main bearing cavity sealing.

[0003] At present, the evaluation method of the floating ring sealing device of the aero-engine mainly includes floating ring floating test and leakage test.

[0004] The floating test mainly evaluates the floating performance of the floating ring. The floating of the floating ring is a necessary condition for the safe and reliable operation of the floating ring seal. Because the graphite ring of the floating ring will not produce hard contact friction or impact wear with the rotating track in the floating state, the safe and reliable operation of the floating ring can be ensured. The initial gap value between the outer circle of the floating sealing ring and the probe of the eddy current sensor and the gap change value in the test are measured by the eddy current sensor, so as to obtain the displacement offset of the floating sealing ring in each direction. The eccentricity of the floating ring and the change curve of the eccentricity of the floating ring with the working condition can be obtained by analysis and calculation, so as to determine whether the floating performance of the floating ring meets the requirements.

[0005] The leakage test includes floating ring sealing gas leakage test and oil leakage test. The leakage test mainly measures the leakage amount of gas and oil under different conditions by changing the pressure in the sealing cavity and the rotating speed of the main shaft. The leakage test evaluates whether the sealing performance of the floating ring seal meets the requirements.

[0006] The existing test evaluation method is not comprehensive, and the current floating ring evaluation test only has floating test and leakage test, which only evaluates the feasibility of the floating ring seal in the working of the aero-engine, and does not verify the reliability of the floating ring seal in the aero-engine. SUMMARY

[0007] The application aims to provide a test evaluation method and system for the floating ring seal device of an aero-engine, and the test evaluation method of the floating ring based on the failure mode is more systematic and comprehensive for the test evaluation of the floating ring, avoids the insufficient reliability and service life of the floating ring seal in the service process, improves the floating ring test evaluation technology, and realizes the standardization, technical generalization and application serialization requirements of the aero-engine graphite material floating ring test evaluation.

[0008] To achieve the above object, the application provides the following technical scheme:

[0009] According to one aspect of the present disclosure, a test evaluation method for a floating ring seal device of an aero-engine is provided, which comprises the following steps:

[0010] Performing a first round of basic test on the floating ring test piece;

[0011] Performing a radial impact and wear test on the floating ring test piece that has performed the first round of basic test;

[0012] Performing a fretting wear test on the floating ring test piece that has performed the radial impact and wear test;

[0013] Performing a second round of basic test on the floating ring test piece that has performed the fretting wear test, and checking whether the floating ring test piece passes the test evaluation.

[0014] In one possible implementation, the basic test comprises a floating test and a leakage test.

[0015] In one possible implementation, the radial impact and wear test on the floating ring test piece that has performed the first round of basic test comprises:

[0016] According to the working condition of the floating ring in the engine, the initial impact force F 碰 and the eccentricity e of the floating ring after stable working are determined;

[0017] The initial impact force F 碰 and the eccentricity e of the floating ring are simulated by a scraping impact and wear test bench, and the test piece after cleaning and drying is installed and debugged;

[0018] The number N of start and stop of the engine in the service life T is counted, and the initial impact force F 碰and the floating ring floating speed n;

[0019] The initial impact force F that the floating ring test piece is subjected to at the time of engine start is applied by the scratch rubbing test bench 碰 ;

[0020] After the floating ring test piece is run N times at the floating ring floating speed n, the test piece is disassembled and inspected, and the floating ring test piece is determined according to the inspection result.

[0021] In a possible implementation, the micro-tribological wear test performed on the floating ring test piece that has undergone the radial rubbing test comprises:

[0022] According to the service condition of the floating ring in the engine, an end face load F is applied to the floating ring test piece that has undergone the radial rubbing test;

[0023] Based on the end face load F, the fractal dimension D, the scale coefficient G and the wear coefficient K of the end face surface topography of the floating ring test piece under the simulated condition are obtained v the law of change over time;

[0024] Based on the law, a micro-tribological wear test mathematical model is constructed by combining the similarity theory;

[0025] The micro-tribological wear test mathematical model is verified and optimized by changing the pv value in the wear test;

[0026] The verified micro-tribological wear test mathematical model is used to calculate an accelerated time t2 equivalent to the life of the floating ring in t1=T hours under the real condition, and the micro-tribological wear test of the floating ring test piece under the simulated condition is performed;

[0027] After the micro-tribological wear test of the floating ring test piece under the simulated condition for time t2, the test piece is disassembled and inspected, and whether the floating ring test piece meets the micro-tribological life requirement is determined according to the inspection result of the topography of the end face of the floating ring test piece.

[0028] In a possible implementation, the expression of the micro-tribological wear test mathematical model is:

[0029]

[0030] In the formula, t1 and t2 are respectively the time of the floating ring in real working condition and the theoretical accelerated time equivalent to the life T in the accelerated life model, and the unit is h; V1 and V2 are respectively the running linear speed of the graphite test block in t1 and t2 test time, and the unit is m / s; E u1 and E u2 are respectively the elastic modulus of the abrasive material in t1 and t2 test time, and the unit is Pa; G1 and G2 are respectively the scale coefficient of the graphite test block to the rubbing surface in t1 and t2 time; δt1 and δ t2 are the wear amounts in the test time t1 and t2, respectively, in units of μm 3 ; p g1 and p g2 are the specific pressures of the wear amounts in the test time t1 and t2, respectively, in units of MPa; Z1, Z2, Z3 are parameters to be determined in the friction and wear acceleration test, and are related to the fractal dimension D, the scale coefficient G, and the wear coefficient K v .

[0031] In one possible implementation, the formula for calculating the fractal dimension D is:

[0032]

[0033] The formula for calculating the scale coefficient G is:

[0034]

[0035] The formula for calculating the coefficient C is:

[0036] C = 10 B ;

[0037] In the formula, k s is the slope of the fractal characteristic surface profile line; B is the intercept of a straight line; γ is a scale parameter; Γ is the second kind of Euler integral Gamma function.

[0038] According to one aspect of the present disclosure, a test evaluation system for an aero-engine floating ring sealing device is provided, and the system comprises: a first round of basic test module, a radial impact and wear test module, a fretting wear test module, and a second round of basic test module; wherein,

[0039] The first basic test module is configured to perform a first round of basic test on the floating ring test piece.

[0040] The radial impact and wear test module is configured to perform a radial impact and wear test on the floating ring test piece that has undergone the first round of basic test.

[0041] The fretting wear test module is configured to perform a fretting wear test on the floating ring test piece that has undergone the radial impact and wear test.

[0042] The second round of basic test module is configured to perform a second round of basic test on the floating ring test piece that has undergone the fretting wear test, and check whether the floating ring test piece passes the test evaluation.

[0043] In one possible implementation, in the first basic test module and the second basic test module, the basic test comprises a floating test and a leakage test.

[0044] In a possible implementation, the radial impact test module comprises a determining unit, an installation and debugging unit, a calculation and analysis unit, a first applying unit and a first determining unit, wherein

[0045] The determining unit is configured to determine the impact force F 碰 and the eccentricity ε of the floating ring after the working stabilization according to the working condition of the floating ring in the engine;

[0046] The installation and debugging unit is configured to simulate the initial impact force F 碰 of the floating ring test piece in the engine start through the scraping impact test bench, and install and debug the test piece after cleaning and drying;

[0047] The calculation and analysis unit is configured to count the start-stop times N of the engine in the service life T, and calculate and analyze the impact force F 碰 and the floating ring floating speed n of the floating ring in the engine start;

[0048] The first applying unit is configured to simulate the impact force F 碰 of the floating ring test piece in the engine start through the scraping impact test bench;

[0049] The first determining unit is configured to run the floating ring test piece at the floating ring floating speed n for N times, disassemble and check after the test, and determine whether the floating ring test piece meets the service life requirement of the floating ring according to the wear check result of the inner side of the floating ring.

[0050] In a possible implementation, the micro-impact wear test module comprises a second applying unit, an obtaining unit, a constructing unit, a verifying and optimizing unit, a calculation unit and a second determining unit, wherein

[0051] The second applying unit is configured to apply the end face load F to the floating ring test piece which has executed the micro-impact wear test according to the service condition of the floating ring in the engine;

[0052] The obtaining unit is configured to obtain the fractal dimension D, the scale coefficient G and the wear coefficient K v of the end face surface morphology of the floating ring test piece under the simulated condition based on the end face load F;

[0053] The constructing unit is configured to construct a micro-impact wear test mathematical model based on the law and the similarity theory;

[0054] The verifying and optimizing unit is configured to verify and optimize the micro-impact wear test mathematical model by changing the pv value in the wear test;

[0055] A calculation unit is configured to calculate an accelerated time t2 corresponding to a T-hour operation under a real working condition by using the verified fretting wear test mathematical model, and to perform a fretting wear test on the floating ring test piece under a simulated working condition for a time t2.

[0056] A second determination unit is configured to disassemble and inspect the floating ring test piece after the fretting wear test under the simulated working condition for a time t2, and to determine whether the floating ring test piece meets the floating ring fretting life requirement according to a topography inspection result of an end surface of the floating ring test piece.

[0057] The present application has the following technical effects and advantages:

[0058] Firstly, the present application divides the evaluation of the floating ring sealing device of the aero-engine into four related tests according to the failure modes, and performs the floating test, the leakage test, the radial rubbing test and the fretting wear test to comprehensively and systematically evaluate the performance of the floating ring, so that the test results are more true and reliable.

[0059] Secondly, the radial rubbing test is performed by using the floating ring scraping and rubbing test bench, which can simulate the working condition of the inner side of the floating ring scraping the runway during the start and stop of the engine and the variable speed process, and the test can evaluate the anti-wear performance of the floating ring under the working condition of the engine.

[0060] Thirdly, the present application combines the test and calculation to perform the fretting wear test. The present application effectively shortens the fretting wear test time by using the fretting wear test mathematical model. According to the test requirement, the T-hour test is relatively long and needs to be completed in one and a half years, however, due to the limitation of test resources, the T-hour test cannot be performed, and the effect of the T-hour fretting wear test needs to be achieved in a limited time. Therefore, the present application calculates the accelerated time t2 corresponding to the T-hour operation under the real working condition by using the fretting wear test mathematical model, and performs the fretting wear test on the floating ring test piece under the floating ring working condition for a time t2. BRIEF DESCRIPTION OF DRAWINGS

[0061] Figure 1 A flow chart of a test evaluation method for the floating ring sealing device of the aero-engine;

[0062] Figure 2 A schematic diagram of the floating ring sealing device of the aero-engine;

[0063] Figure 3 A schematic diagram of the failure mode position of the floating ring test piece of the floating ring sealing device of the aero-engine;

[0064] Figure 4 A schematic diagram of the floating ring test piece of the floating ring sealing device of the aero-engine;

[0065] Figure 5 is a collision failure mode position schematic diagram of the present application;

[0066] Figure 6 is a fretting wear failure mode position schematic diagram of the present application;

[0067] Figure 7 is a flow chart of a series test of the present application;

[0068] In the figure, 1 is a shell, 2 is a floating ring, 3 is a runway, 4 is a gasket, 5 is a wave spring, and 6 is a check ring. DETAILED DESCRIPTION

[0069] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0070] To solve the problems in the prior art, on the one hand, the present application discloses a test and evaluation method for an aero-engine floating ring sealing device, Figure 1 is a flow chart of a test and evaluation method for an aero-engine floating ring sealing device of the present application, as Figure 1 shown, the method comprises the following steps:

[0071] Step S1, performing a first round of basic test (including floating test and leakage test) on the floating ring test piece;

[0072] Step S2, performing a radial impact wear test on the floating ring test piece that has performed the first round of basic test;

[0073] Step S3, performing a fretting wear test on the floating ring graphite test block that has performed the impact wear test;

[0074] Step S4, performing a second round of basic test (consistent with the first round of floating test and leakage test, checking the floating and sealing performance of the floating ring test piece after the radial impact wear test and the fretting wear test) on the floating ring test piece that has performed the fretting wear test, and checking whether the floating ring test piece passes the test and evaluation.

[0075] The floating ring graphite sealing is a non-contacting circumferential graphite sealing, Figure 2 is a schematic diagram of an aero-engine floating ring sealing device of the present application, as Figure 2As shown, the aero-engine floating ring sealing device is composed of a shell 1, a floating graphite sealing ring (i.e. a floating ring 2), a first runway 3, a gasket 4, a wave spring 5, and a check ring 6, and its function is to effectively isolate the bearing cavity of the engine rotor system from the airflow environment of the engine, to protect the bearing and the lubricating oil from the damage of the high-temperature airflow environment, and to prevent the leakage of the lubricating oil in the bearing cavity to the outside of the cavity.

[0076] The failure of the floating ring seal causes the leakage of the aero-engine gas and lubricating oil to exceed the standard, and even causes serious oil leakage, which greatly endangers the safety of the aero-engine, Figure 3 Figure 1 is a schematic diagram of the failure mode position of the floating ring test piece of the aero-engine floating ring sealing device of the present application, Figure 3 In the figure, the No. ① box represents the fretting wear failure mode, and the No. ② box represents the floating up failure mode and the collision wear failure mode.

[0077] Specifically, from the service process and test results of the floating ring seal on the aero-engine, the main failure modes of the floating ring seal include: the floating up failure mode, the collision wear failure mode and the fretting wear failure mode; wherein,

[0078] (1) Floating up failure mode: Figure 4 Figure 2 is a schematic diagram of the floating up failure mode of the present application, as shown, Figure 4 The floating ring does not continue to float in the radial direction under the working condition of the floating ring, causing the scraping of the floating ring and the counterpart, increasing the inner diameter of the graphite ring in the floating ring, and causing the leakage to exceed the standard;

[0079] (2) Collision wear failure mode: Figure 5 Figure 3 is a schematic diagram of the collision failure mode of the present application, as shown, Figure 5 The collision between the graphite ring in the floating ring and the runway causes the floating ring to break and the edge to collapse, resulting in the failure of the main sealing surface;

[0080] (3) Fretting wear failure mode: Figure 6 Figure 4 is a schematic diagram of the fretting wear failure mode of the present application, as shown, Figure 6 In the operation of the floating ring seal, the persistent fretting wear between the end face of the graphite ring in the floating ring and the shell causes the failure of the sealing end face.

[0081] The evaluation method for the aero-engine floating ring sealing device of the present application, in view of the collision wear and fretting wear failure modes of the floating ring in the operation of the aero-engine, increases the floating ring radial collision wear test and the floating ring fretting wear test on the basis of the existing floating up test and leakage test. Figure 7 Figure 5 is a flow chart of the series evaluation of the floating ring of the present application, as shown, Figure 7As shown, after the first round of floating test and the first round of leakage test, the floating ring test piece sequentially passes through the floating ring radial rubbing test and the floating ring fretting wear test, and then passes through the second round of floating test and the second round of leakage test, and finally it can be determined whether the test piece passes the test. It should be noted that the order of the floating test and the leakage test in the first round and the second round of basic test can be changed, and the order of the radial rubbing test and the fretting wear test can also be changed.

[0082] Floating test: The main function is to simulate the engine working condition and installation condition, and the initial gap value between the outer circle of the floating seal ring and the eddy current sensor probe and the gap change value during the test are measured by the eddy current sensor, thereby obtaining the displacement offset of the floating seal ring in each direction, obtaining the variation rule of the floating ring eccentricity of the floating ring test piece with the rotating speed under the condition working condition, and obtaining the floating performance of the floating ring under the condition working condition; mainly composed of floating test adapter, fixture, eddy current sensor and other analysis software. Check whether the eccentricity of the floating ring under the engine working condition reaches the evaluation index, if it reaches the evaluation index, proceed to the next test, if the eccentricity exceeds the evaluation index, continue to debug the floating test or replace / inspect the test piece and then proceed to the floating test.

[0083] Leakage test: The main function is to simulate the engine working condition and installation condition, and the leakage amount of the floating ring test piece under the condition working condition is tested, and the sealing performance of the floating ring test piece under the condition working condition is obtained; if the leakage amount under the working condition does not exceed the evaluation index, the next round of test is carried out, if the leakage amount under the working condition exceeds the evaluation index, the test piece is checked or replaced and the leakage test is continued; mainly composed of leakage test adapter, flowmeter, thermometer, etc.

[0084] Radial rubbing test: The main function is to simulate the scraping rubbing failure mode of the engine floating ring under the condition working condition, so as to quickly and effectively check the scraping rubbing capacity of the floating ring test piece, mainly composed of cam, force applying structure, heating box and shell, etc. The radial rubbing test is carried out on the floating ring scraping rubbing test bench. Specifically, first, the number of starts and stops N within the life T of the floating ring in the engine is determined according to the working condition of the floating ring in the engine; the collision force F 碰 experienced by the floating ring when the engine starts is calculated and analyzed, and the floating ring floating speed n is calculated and analyzed. The loading mechanism in the scraping rubbing test bench can simulate the collision force F 碰 experienced by the floating ring when the engine starts, and the test runs N times at the floating ring floating speed n, then the test bench is disassembled for inspection. If there is no obvious grinding mark, block-shaped material falling off or even floating ring rupture on the inner diameter of the graphite ring, it means that the radial rubbing life of the floating ring seal within the T period meets the requirements, and the floating ring test piece meets the life requirements from the aspect of radial rubbing failure mode.

[0085] Fretting wear test: the main function is to obtain the temperature, pressure and other conditions of the fretting wear test according to the working conditions of the floating ring seal in the service process of the aero-engine. Usually, the floating ring graphite test block fretting wear test is carried out on the high temperature fretting wear test machine. Specifically, first, according to the service working condition of the floating ring in the engine, the floating ring test piece is subjected to end face load F on the high temperature fretting wear test machine, the fretting wear test under the working condition of the floating ring is carried out, and the fractal dimension D, scale coefficient G and wear coefficient K of the floating ring test piece to the grinding surface under the simulated working condition are obtained v The law of change with time, combined with the similarity theory, a mathematical model of fretting wear accelerated life test is constructed; by changing the pv value (p value represents the end face specific pressure of the test piece, v represents the linear speed of the test piece in the fretting wear test, and pv value is generally used to measure the allowable working capacity of the sealing friction pair), the mathematical model of fretting wear test is verified and optimized; the verified friction and wear test mathematical model is used to determine the maximum pv value allowed in the test according to the fretting wear test machine, to calculate the accelerated time t2 equivalent to t1=T hours (engine working life) running under the real working condition, and to carry out high temperature fretting wear test on the floating ring test piece.

[0086] Further, based on the fractal theory, an accelerated life model of the floating ring seal is established, and the fractal dimension D, scale coefficient G and wear coefficient K of the floating ring test piece under the simulated working condition are obtained v The law of change with time, combined with the similarity theory, the undetermined coefficients Z1, Z2 and Z3 of the model are obtained, and a mathematical model of fretting wear accelerated life test is constructed, and the expression is:

[0087]

[0088] In the formula, t1 and t2 are respectively the time of the real working of the floating ring and the theoretical accelerated time equivalent to the total life T in the accelerated life model, and the unit is h; V1 and V2 are respectively the linear speed of the graphite test block in t1 and t2 test time, and the unit is m / s; E u1 and E u2 are respectively the elastic modulus of the grinding material in t1 and t2 test, and the unit is Pa; G1 and G2 are respectively the scale coefficient of the graphite test block to the grinding surface in t1 and t2 time; δ t1 and δ t2 are respectively the wear amount in t1 and t2 test time, and the unit is μm 3 ; p g1 and p g2 are respectively the end face specific pressure of the wear amount in t1 and t2 test time, and the unit is MPa; Z1, Z2 and Z3 are the undetermined parameters in the friction and wear accelerated test, which are related to the fractal dimension D, scale coefficient G and wear coefficient K v .

[0089] The calculation formula of fractal dimension D is:

[0090]

[0091] The calculation formula of scale coefficient G is:

[0092]

[0093] The calculation formula of coefficient C is:

[0094] C = 10 B ; (4)

[0095] In the formula, k s is the slope of the fractal feature surface profile line; B is the intercept of a straight line; γ is the scale parameter; Γ is the second kind of Euler integral Gamma function.

[0096] The formula (2), (3) and (4) are brought into the formula (5) to obtain the relationship equation of D (t) -t and the scale coefficient G (t) with time t through experimental data regression, and D

[0097]

[0098] In the formula, Ar* is the ratio of actual contact area to nominal contact area, i.e. Ar* = Ar / Aa; Ar is the actual contact area, m2; Aa is the nominal contact area, m2; is the ratio of critical contact area to nominal contact area, i.e. a c is the critical contact area; ape* is the critical contact area of plastic deformation to elastic-plastic deformation, m2; is the ratio of elastic modulus of friction pair; bf is the width of sealing surface, unit: m; pg is the specific load of sealing end face, unit: Pa; E is the equivalent elastic modulus, unit: Pa; K is the ratio of hardness to yield strength of graphite material; H is the hardness of graphite material, unit: Pa; η is the dynamic viscosity of medium, unit: Pa·s; δt is the wear amount within t time, unit: μm3; t is the time, unit: s.

[0099] Two groups of working condition parameters are brought into the formula (5) to obtain the equation (1), and then Z1, Z2 and Z3 are obtained.

[0100] Second round of floating test and leakage test: after the fretting wear test, the floating ring will be subjected to a second round of floating test and leakage test on the seal structure tester. The floating test is the same as the first round of floating test. If the maximum eccentricity of the floating ring is not greater than the evaluation index, it is considered that the floating ring passes the second round of floating test. The leakage test is the same as the first round of leakage test. If the leakage amount of lubricating oil is still less than or equal to the evaluation index, it is considered that the lubricating oil sealing performance of the graphite material sealing ring meets the project index.

[0101] After the floating test, the leakage test, the radial impact test and the fretting wear test, if the floating ring passes the above evaluation tests and the leakage performance still meets the technical index requirements after T hours, the evaluation and verification of the graphite material floating ring is completed.

[0102] In summary, the present application divides the evaluation and verification of the aero-engine floating ring seal device into four related test evaluations according to the fault mode, and performs the impact test, the fretting wear test, the floating test and the leakage test to systematically evaluate the performance of the floating ring.

[0103] The fretting wear accelerated life test method is combined with test and calculation. The fretting wear accelerated life test mathematical model is constructed by using the similarity theory; the fretting wear accelerated life test mathematical model is verified and optimized by changing the pv value in the test; the floating ring test piece is subjected to high temperature fretting wear test by using the verified calculation and the accelerated time t2 equivalent to the t1=T hours operation under the real working condition. The method for series evaluation and verification of the graphite material floating ring has been used in the implementation scheme for the evaluation and verification of the graphite ring for the floating ring seal, and the test method research and the related test have been completed.

[0104] Based on the above method, in another aspect, the present application discloses a test evaluation system for an aero-engine floating ring seal device, the system comprising: a first round of basic test module, a radial impact test module, a fretting wear test module and a second round of basic test module; wherein the first round of basic test module is used to perform a first round of basic test on the floating ring test piece; the radial impact test module is used to perform a radial impact test on the floating ring test piece which has performed the first round of basic test; the fretting wear test module is used to perform a fretting wear test on the floating ring test piece which has performed the radial impact test; the second round of basic test module is used to perform a second round of basic test on the floating ring test piece which has performed the fretting wear test, and check whether the floating ring test piece passes the test evaluation.

[0105] Further, in the first basic test module and the second basic test module, the basic test includes a floating test and a leakage test.

[0106] Further, the radial impact test module comprises a determination unit, an installation and debugging unit, a calculation and analysis unit, a first application unit and a first determination unit; wherein the determination unit is configured to determine the impact force F 碰 experienced by the floating ring test piece during engine startup according to the working condition of the floating ring in the engine 碰 , the eccentricity of the floating ring ε, and the installation and debugging unit is configured to install and debug the test piece after cleaning and drying by simulating the initial impact force F 碰 experienced by the floating ring test piece during engine startup by the scraping impact test bench 碰 ; the first determination unit is configured to disassemble and inspect the floating ring test piece after running N times at the floating ring floating speed n, and determine the floating ring test piece according to the inspection result.

[0107] Further, the micro-impact wear test module comprises a second application unit, an obtaining unit, a construction unit, a verification and optimization unit, a calculation unit and a second determination unit, wherein the second application unit is configured to apply an end face load F to the floating ring test piece that has undergone the radial impact test according to the service condition of the floating ring in the engine; the obtaining unit is configured to obtain the fractal dimension D, the scale coefficient G and the wear coefficient K v of the end face surface morphology of the floating ring test piece under simulated conditions based on the end face load F; the construction unit is configured to construct a micro-impact wear test mathematical model based on the law and the similarity theory; the verification and optimization unit is configured to verify and optimize the micro-impact wear test mathematical model by changing the pv value in the wear test; the calculation unit is configured to calculate the accelerated time t2 equivalent to the floating ring life running for t1=T hours under real conditions by using the verified micro-impact wear test mathematical model, and perform micro-impact wear test of the floating ring test piece under simulated conditions; and the second determination unit is configured to disassemble and inspect the floating ring test piece after the micro-impact wear test under simulated conditions for time t2, and determine whether the floating ring test piece meets the micro-impact life requirement of the floating ring according to the inspection result of the morphology of the end face of the floating ring test piece.

[0108] Finally, it should be noted that the above description is only the preferred embodiments of the present application, and is not intended to limit the present application. Although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art will appreciate that the technical solutions described in the foregoing embodiments can be modified or equivalent replacements can be made to some of the technical features, and any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A method for testing a floating ring seal assembly for an aircraft engine, the method comprising: The method comprises the following steps: performing a first round of basic tests on the floating ring test piece; performing a radial rubbing test on the floating ring test piece that has undergone the first round of basic tests, and comprising: According to the working condition of the floating ring in the engine, the initial collision force F suffered by the floating ring test piece when the engine starts is determined 碰 and the eccentricity after the work is stable ε ; The initial impact force F that the floating ring test piece receives at the time of engine starting is simulated by a scratch rubbing test bench 碰 and the eccentricity of the floating ring ε and the test piece after cleaning and drying is installed and debugged; Count the number of starts N of the engine in the life T, calculate and analyze the initial impact force F suffered by the floating ring when the engine starts 碰 and the floating ring floating speed n; The initial impact force F that the float ring test piece receives at the time of engine start is applied by a scratch rubbing test bench 碰 ; after the floating ring test piece is run N times at the floating ring floating speed n, the test piece is disassembled and inspected, and the floating ring test piece is determined according to the inspection result; The method further comprises: performing a fretting wear test on the floating ring test piece that has undergone the radial rubbing test; performing a second round of basic tests on the floating ring test piece that has undergone the fretting wear test to check whether the test piece passes the test.

2. A method of testing a floating ring seal for an aeroengine as claimed in claim 1, wherein, The basic test comprises a floating test and a leakage test.

3. A method of testing a floating ring seal for an aeroengine as claimed in claim 1 or 2, wherein, The fretting wear test on the floating ring test piece that has undergone the radial rubbing test comprises: Applying an end face load to the floating ring test piece that has performed the radial rub test according to the service condition of the floating ring of the engine F； based on the end face load F , obtain the fractal dimension of the end face surface morphology of the floating ring test piece under the simulated working condition D , scale coefficient G and wear coefficient K v law of change with time; based on the law, a mathematical model of the fretting wear test is constructed by combining the similarity theory; by varying the values of the wear test pv the fretting wear test mathematical model is verified and optimized, p is the end face specific pressure experienced by the test piece, v is the linear speed at which the test piece is run in the fretting wear test; using the verified mathematical model of the fretting wear test, an accelerated time t2 equivalent to the life of the floating ring under the true working condition within t1=T hours is calculated, and a fretting wear test under simulated working conditions is performed on the floating ring test piece, T being the total life; after the floating ring test piece is run for time t2 under simulated working conditions, the test piece is disassembled and inspected, and the floating ring test piece is determined according to the inspection result of the end surface topography of the floating ring test piece to determine whether the floating ring test piece meets the fretting life requirement.

4. A method of testing a floating ring seal for an aeroengine as claimed in claim 3, wherein, The expression of the mathematical model of the fretting wear test is: ； Wherein, t1 and t2 are respectively the time when the floating ring is actually working and the theoretical accelerated time corresponding to the life T in the accelerated life model, and the unit is h; V 1 and V 2 are respectively the running linear velocity of the graphite test block in the t1 and t2 test time, and the unit is m / s; u1 and E u2 are respectively the elastic modulus of the grinding material in the t1 and t2 test time, and the unit is Pa; G 1 and G 2 are respectively the size coefficient of the graphite test block against the grinding surface in the t1 and t2 time; δ t1 and δ t2 are respectively the wear amount in the t1 and t2 test time, and the unit is μm 3 ; p g1 and p g2 are respectively the end face specific pressure of the wear amount in the t1 and t2 test time, and the unit is MPa; Z1, Z2, Z3 are the undetermined parameters in the friction and wear accelerated test, which are related to the fractal dimension D , size coefficient G , and wear coefficient K v .

5. The test evaluation method for the floating ring sealing device of an aero-engine according to claim 4, characterized in that, The fractal dimension D The calculation formula is: ； the calculation formula of the scale coefficient G is: ； the calculation formula of the coefficient C is: ； wherein k s is the slope of the fractal feature surface profile line; B is the intercept of the straight line; γ is the scale parameter; and Γ is the second kind Euler integral Gamma function.

6. A test and evaluation system for a floating ring seal assembly of an aircraft engine, comprising: The system comprises a first round of basic test module, a radial rubbing test module, a fretting wear test module and a second round of basic test module; wherein, the first basic test module is used for performing a first round of basic tests on the floating ring test piece; the radial rubbing test module is used for performing a radial rubbing test on the floating ring test piece that has undergone the first round of basic tests, and the radial rubbing test module comprises a determination unit, an installation and debugging unit, a calculation and analysis unit, a first application unit and a first determination unit; wherein, The determining unit is configured to determine the collision force F that the floating ring test piece receives when the engine starts according to the working condition of the floating ring in the engine 碰 and the eccentricity after the working is stable ε ; The installation and adjustment unit is used for simulating the initial impact force F that the floating ring test piece receives at the time of engine starting through the scratch impact test bench 碰 and the eccentricity of the floating ring ε and the test piece after cleaning and drying is installed and adjusted; The computing and analyzing unit is used for counting the number of start-stop times N of the engine in the life T, and calculating and analyzing the impact force F suffered by the floating ring when the engine starts 碰 and the floating ring floating rotation speed n; a first application unit for applying an initial impact force F that the float ring test piece receives at the time of engine start by a scratch rig test bench 碰 ; the first determination unit is used for disassembling and inspecting the floating ring test piece after the floating ring test piece is run N times at the floating ring floating speed n, and determining the floating ring test piece according to the inspection result; the fretting wear test module is used for performing a fretting wear test on the floating ring test piece that has undergone the radial rubbing test; the second round of basic test module is used for performing a second round of basic tests on the floating ring test piece that has undergone the fretting wear test to check whether the test piece passes the test.

7. A test and evaluation system for a floating ring seal assembly of an aircraft engine as set forth in claim 6, characterized in that, In the first basic test module and the second basic test module, the basic test comprises a floating test and a leakage test.

8. A test and evaluation system for a floating ring seal assembly of an aeroengine according to claim 6 or 7, characterized in that The fretting wear test module comprises a second application unit, an obtaining unit, a construction unit, a verification and optimization unit, a calculation unit and a second determination unit, wherein, The second application unit is used to apply end face loads to the floating ring test piece that has undergone the radial impact rubbing test, according to the service conditions of the floating ring in the engine. F； The obtaining unit is used to obtain the end face load. F The fractal dimension of the surface morphology of the end face of the floating ring test piece under simulated working conditions was obtained. D Scale factor G and wear coefficient K v The pattern of change over time; the construction unit is used for constructing a mathematical model of the fretting wear test based on the law and combining the similarity theory; a verification and optimization unit for verifying and optimizing the fretting wear test mathematical model by changing the values of pv the specific pressure on the end face of the test piece, p the specific pressure on the end face of the test piece, v the linear velocity of the test piece running in the fretting wear test; A calculation unit is configured to calculate an accelerated time t2 corresponding to a life of the floating ring under a real working condition within t1=T hours by using the verified micro-tribological wear test mathematical model, and to perform a micro-tribological wear test of the floating ring test piece under the simulated working condition. A second determination unit is configured to disassemble and inspect the floating ring test piece after the micro-tribological wear test of the floating ring test piece under the simulated working condition for the time t2, and to determine whether the floating ring test piece meets the micro-tribological life requirement of the floating ring according to a result of a topography inspection of an end surface of the floating ring test piece.

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