CN115640666A - Aero-engine acceleration task test chart compiling method based on damage equivalence - Google Patents
Aero-engine acceleration task test chart compiling method based on damage equivalence Download PDFInfo
- Publication number
- CN115640666A CN115640666A CN202210880296.5A CN202210880296A CN115640666A CN 115640666 A CN115640666 A CN 115640666A CN 202210880296 A CN202210880296 A CN 202210880296A CN 115640666 A CN115640666 A CN 115640666A
- Authority
- CN
- China
- Prior art keywords
- spectrum
- damage
- slow
- acceleration
- load
- 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.)
- Granted
Links
- 230000006378 damage Effects 0.000 title claims abstract description 99
- 238000012360 testing method Methods 0.000 title claims abstract description 96
- 230000001133 acceleration Effects 0.000 title claims abstract description 75
- 238000000034 method Methods 0.000 title claims abstract description 53
- 238000001228 spectrum Methods 0.000 claims abstract description 126
- 230000007774 longterm Effects 0.000 claims abstract description 34
- 238000009825 accumulation Methods 0.000 claims abstract description 31
- 238000009668 long-life test Methods 0.000 claims abstract description 12
- 230000008569 process Effects 0.000 claims description 12
- 230000008859 change Effects 0.000 claims description 10
- 230000014759 maintenance of location Effects 0.000 abstract description 3
- 238000007619 statistical method Methods 0.000 abstract 1
- 230000035882 stress Effects 0.000 description 17
- 239000000463 material Substances 0.000 description 13
- 238000010586 diagram Methods 0.000 description 11
- 230000009471 action Effects 0.000 description 5
- 230000000694 effects Effects 0.000 description 4
- 238000011160 research Methods 0.000 description 4
- 238000011084 recovery Methods 0.000 description 3
- 230000035939 shock Effects 0.000 description 3
- 230000009286 beneficial effect Effects 0.000 description 2
- 238000013461 design Methods 0.000 description 2
- 229910000601 superalloy Inorganic materials 0.000 description 2
- 238000005266 casting Methods 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 230000008878 coupling Effects 0.000 description 1
- 238000010168 coupling process Methods 0.000 description 1
- 238000005859 coupling reaction Methods 0.000 description 1
- 125000004122 cyclic group Chemical group 0.000 description 1
- 230000001419 dependent effect Effects 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 230000018109 developmental process Effects 0.000 description 1
- 238000011156 evaluation Methods 0.000 description 1
- 238000000605 extraction Methods 0.000 description 1
- 230000006870 function Effects 0.000 description 1
- 230000000977 initiatory effect Effects 0.000 description 1
- 230000003446 memory effect Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012545 processing Methods 0.000 description 1
- 238000011002 quantification Methods 0.000 description 1
- 230000008929 regeneration Effects 0.000 description 1
- 238000011069 regeneration method Methods 0.000 description 1
- 230000035945 sensitivity Effects 0.000 description 1
- 230000008646 thermal stress Effects 0.000 description 1
Images
Classifications
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
- Y02T90/00—Enabling technologies or technologies with a potential or indirect contribution to GHG emissions mitigation
Landscapes
- Investigating Strength Of Materials By Application Of Mechanical Stress (AREA)
Abstract
The invention discloses a damage equivalence-based method for compiling an aircraft engine acceleration task test run spectrum, which comprises the following specific steps of: s1: dividing a long-life test run spectrum into an initial section, a middle section and an end section; s2: carrying out statistical analysis on the middle section of the long-term life test run spectrum to obtain load information such as secondary cycle, load retention time, throttle lever switching rate and the like required for compiling an acceleration spectrum; s3: accelerating the load information needing to be accelerated by selecting a fatigue and creep damage accumulation model; s4: and arranging the accelerated slow vehicle-maximum-slow vehicle circulation, the maximum power state duration and other load information to obtain an accelerated task trial run spectrum. The compiled test run spectrum of the acceleration task is verified by tests to be equivalent to the test run spectrum of the long service life.
Description
Technical Field
The invention relates to the technical field of aero-engine structure life test evaluation, in particular to an aero-engine acceleration task test spectrum compiling method based on damage equivalence.
Background
According to the definition of the American air force, the accelerated task test is a simulated task test which is performed on a ground test bed frame by an engine, shortens the test time and is equivalent to the full-life real-time test, and is also called accelerated equivalent durability test. The method is used for checking the durability, reliability and service life of the engine, can expose faults which may occur in the use of the aircraft engine in an external field in a short time, can save test-run expenses and accelerate the development progress, and is an effective means for researching the service life of the aircraft engine. Aeroengines such as America and Russia have been widely used for accelerating the mission and testing the structural life of the engines.
The key of the accelerated task test run is to compile an accelerated task test run spectrum equivalent to the damage of the long-term life test run spectrum. In recent years, although many beneficial researches are conducted on acceleration task test run in China, the acceleration task test run is written into GJB241A-2010 general specifications of aviation turbojet and fan engines as a test requirement necessary for a design and design stage, the implementation of the specifications is difficult due to the lack of a quantitative and standardized acceleration task test run spectrum compiling method in China at present. Therefore, it is urgently needed to establish a method for compiling an aircraft engine acceleration task trial-run spectrum based on a damage equivalence principle, and to realize quantification and standardization of a spectrum compiling process.
Disclosure of Invention
In order to solve the problems, the invention provides a method for compiling an aircraft engine acceleration task test run spectrum based on damage equivalence.
In order to achieve the purpose, the invention is realized by the following technical scheme:
the invention relates to a method for compiling an aircraft engine acceleration task test run spectrum based on damage equivalence, which comprises the following steps:
s1, carrying out stage division on a long-life test run spectrum, and dividing the long-life test run spectrum into an initial section, a middle section and an end section;
s2, carrying out load characteristic analysis on the middle section of the long-life test run spectrum, and extracting load characteristic information, including a secondary cycle, load-holding state duration and throttle lever switching rate;
s3, selecting a fatigue damage accumulation model to equivalently accelerate the secondary cycle load, and selecting a creep damage accumulation model to equivalently accelerate the duration time of the load-holding state;
and S4, arranging the accelerated load spectrum by combining the load characteristic information of the long-term life test spectrum to obtain an accelerated task test spectrum.
The invention is further improved in that: s2 specifically comprises the following steps:
s2.1, extracting the number of secondary cycles comprising slow vehicle-maximum-slow vehicle, cruise-maximum-cruise, cruise-military thrust-cruise, slow vehicle-cruise-slow vehicle and military thrust-maximum-military thrust by using a rain flow counting method;
s2.2, identifying the load-holding state by using the small-range fluctuation of the rotating speed not more than 3%, counting the duration time of different load-holding states, analyzing the duration time of the maximum state and the duration time of the slow vehicle state in the circulation process, and obtaining the average value of the duration time of the maximum state
Average of slow-speed state duration
And standard deviation;
s2.3, respectively counting the change rate of the rotating speed of the throttle rod in the acceleration and deceleration processes, and analyzing the distribution characteristics and the average value of the average change rate of the rotating speed in the acceleration stage
Average rate of change of speed in deceleration phase
。
The invention is further improved in that: s3 specifically comprises the following steps:
s3.1, calculating the sum of the damage caused by each stage of circulation by using a low-cycle fatigue damage accumulation criterion, and then according to a damage equivalence principle, equating fatigue damage to a slow car-maximum-slow car circulation, wherein the number of the equivalent circulation is calculated as follows:
wherein,
the number of the secondary circulation stages is the same as that of the secondary circulation stages,
for calculation using fatigue damage accumulation model
The damage to the secondary cycle is a result of,
damage caused by one slow-max-slow cycle.
S3.2, calculating the sum of creep damage caused by each stage of load-holding states by using a creep damage accumulation criterion, and then equivalently accelerating the creep damage caused by each stage of load-holding states to be in a maximum state according to a damage equivalence principle, wherein the time after equivalent acceleration is calculated as:
wherein,
the total number of the loading states in the long-term life test run spectrum,
calculated for using a creep damage accumulation model
Creep damage in the secondary load-holding state,
test run for long term serviceThe total number of the stages of the vehicle state,
calculated for using a creep damage accumulation model
The creep damage in the slow-moving state,
the creep damage is the maximum state creep damage per unit time calculated by using a creep damage accumulation model.
The invention is further improved in that: s4 specifically comprises the following steps:
s4.1, determining an initial section and an end section of the accelerated task trial spectrum;
s4.2, arranging a slow vehicle-maximum-slow vehicle cycle;
s4.3, arranging the maximum state duration.
The invention is further improved in that: s4.2 is specifically operative to: arranging and totaling
Individual slow-max-slow cycle, wherein slow state duration in a cycle is taken as the sub-cycle average slow-start duration in the long-term life test run spectrum
The maximum state duration in the cycle is taken as the average maximum state duration of the secondary cycle in the long-term life test spectrum
Duration of the acceleration phase
Calculating the average rotating speed change rate of the acceleration stage in the long-term service life test run spectrum according to the following formula:
wherein,
the maximum state rotating speed is set as the rotating speed of the motor,
the rotating speed is in a slow vehicle state.
The invention is further improved in that: s4.3 the duration of the maximum state is divided into two parts, the concentrated maximum state phase and the maximum state phase contained in the slow-slow cycle, wherein the duration of the concentrated maximum state phase
Calculated from the following formula:
the beneficial effects of the invention are: the method realizes the damage equivalence of the accelerated task test run spectrum and the long-term life test run spectrum, provides technical support for the application of the accelerated task test run method in the life test run work of the engine in China, and provides guarantee for the implementation of the related requirements on the accelerated task test run in the GJB 241A-2010.
Drawings
FIG. 1 is a flow chart of a programming technique of an aircraft engine acceleration mission trial spectrum based on damage equivalence.
FIG. 2 is a schematic diagram of the acceleration load required by the acceleration mission commissioning spectrum and the acceleration method.
Fig. 3 is a schematic diagram of an accelerated task trial spectrum arrangement method.
Fig. 4 is a schematic diagram of the stage division result of the long-term life trial run spectrum.
FIG. 5 is a diagram of a long-term life test run spectrum for a certain type of engine.
FIG. 6 is a schematic representation of the conversion of a rotational rate spectrum to a stress spectrum.
Fig. 7 is a schematic diagram of throttle lever switching rate distribution of a long-life test run spectrum in an acceleration phase.
Fig. 8 is a schematic diagram of the throttle lever switching rate distribution of the long-life trial run spectrum in the deceleration stage.
Fig. 9 is a schematic diagram showing the distribution of the maximum state of the long-term life test spectrum.
Fig. 10 is a diagram illustrating a distribution of slow-moving states in a long-term life test spectrum.
FIG. 11 is a diagram of the acceleration task trial spectrum finally programmed and obtained by the present invention.
Fig. 12 is a schematic diagram of the comparison between the accelerated task trial spectrum and the long-term life trial spectrum finally obtained by compilation.
FIG. 13 is a schematic diagram of a test piece for testing the damage consistency of an accelerated task test run spectrum and a long-term life test run spectrum according to the present invention.
FIG. 14 is a graphical representation of experimental creep deformation as a function of the number of cycles of the trial spectrum.
DETAILED DESCRIPTION OF EMBODIMENT (S) OF INVENTION
In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention, so that a person skilled in the art can implement the technical solutions by referring to the description text.
As shown in fig. 1, the method for compiling the acceleration mission trial spectrum of the aero-engine based on damage equivalence specifically comprises the following steps:
s1, carrying out stage division on the long-life test run spectrum, and dividing the long-life test run spectrum into an initial section, a middle section and an end section by taking the maximum state reached for the first time and the maximum state reached for the last time as a demarcation point.
Processing the middle section of the long-life test run spectrum;
according to the earlier developed long-term life test chart of certain type of engine shown in fig. 5, according to previous research experience, the typical service stress of GH4169 material turbine disk in the maximum state is about 850MPa, and therefore, the rotating speed spectrum can be converted into a stress spectrum, as shown in fig. 6.
And extracting information of a secondary cycle (fatigue), a small power state (creep) and a throttle lever switching rate (thermal shock) which need to be accelerated based on the stress profile of the given long-term life trial run spectrum, and providing load input for the compilation of an acceleration spectrum. The method comprises the following specific steps:
(1) Sub-cycle signature analysis
The information of the sub-cycle load requiring acceleration is shown in table 1:
as can be seen from the above table, specific cycle types include: the equivalent acceleration method for the secondary cycle comprises the steps of converting damage generated by the secondary cycle into a slow vehicle-maximum-slow vehicle cycle according to a damage equivalent principle.
(2) Load state feature analysis
Creep load (part) information for low power states requiring acceleration is shown in table 2:
creep damage is caused by creep deformation of structures such as an engine turbine disc and the like caused by high temperature and high rotating speed in the service process. The information that needs to be counted therefore includes: rotational speed (stress), temperature, dwell time, etc. Because the temperature generally has a coupling relation with the rotating speed, and a load extraction method and an equivalent acceleration method are mainly discussed in the invention, in order to verify the equivalent realizability of the long test spectrum and the acceleration spectrum damage through subsequent tests, the typical service temperature of the dangerous point of the GH4169 material turbine disk is uniformly assumed to be 650 ℃. The assumption does not influence the applicability of the spectrum coding method, and in the acceleration task trial spectrum coding work of the actual model engine, according to the temperature-stress analysis results of key parts such as a turbine disc and the like in different states, the creep damage of the dangerous point of the turbine disc in the low-power state is obtained by combining the extracted low-power state duration time information, namely, the low-power state can be equivalently accelerated to the maximum power state by adopting the creep damage equivalent acceleration criterion.
(3) Throttle lever switching rate characteristic analysis
Thermal shock loads in the engine are caused by thermal stress on high-temperature runner parts such as a flame tube, turbine rotor and stator blades caused by runner temperature change caused by pushing a throttle lever by a pilot. In order to ensure that the thermal shock damage of the accelerated task test run spectrum is equivalent to that of the long-term life test run spectrum, the switching rate of throttle levers in the accelerated task test run spectrum and the long-term life test run spectrum is required to be ensured to be consistent. By counting the distribution characteristics of the stress switching rate in the stress spectrum of the long-term life test run spectrum, a basis is provided for determining the throttle lever switching rate in the process of compiling the acceleration task test run spectrum.
The throttle lever switching rate distribution of the long-term life trial spectrum in the acceleration stage is shown in fig. 7, the throttle lever switching rate in the acceleration stage approximately follows normal distribution, the mean value is 1.195, the standard deviation is 0.481, and the average time corresponding to the acceleration from the slow vehicle state to the maximum state is 25.1s.
The throttle lever switching rate distribution of the long-term life trial spectrum in the deceleration stage is shown in fig. 8, the throttle lever switching rate in the deceleration stage approximately follows normal distribution, the mean value is 1.279, the standard deviation is 0.467, and the average time corresponding to deceleration from the maximum state to the slow driving state is 23.5s.
The equivalent acceleration is carried out on the load needing to be accelerated in the long-life test run spectrum. The sub-cycle load is accelerated by a low-cycle fatigue damage equivalent method, and the load-holding state (including the maximum state) is accelerated by a creep damage equivalent method.
Because the load spectrum of the engine has quasi-random spectrum characteristics, the size and the number of load cycles and the stress size and the time of a load holding state have certain dispersivity, and the error is larger when the fatigue and creep damage failure model under the conventional constant amplitude spectrum is adopted for carrying out equivalent acceleration, so that a nonlinear damage accumulation model is required to be selected for carrying out equivalent acceleration on the load characteristics.
The invention adopts the following two equivalent methods:
(1) Low-cycle fatigue damage equivalent method
(2) Since fatigue life is not only dependent on stress magnitude but also affected by load history. Sum of injuries due to exercise effect of low stress in low-high load sequence
Typically greater than 1; in the high-low order, the fatigue cracks can also propagate under low stress due to the initiation, and the sum of the damage
Typically less than 1.
The invention adopts a multi-stage nonlinear fatigue damage accumulation model based on the material memory effect, the model considers the influence of average stress and complex load, and the damage calculation formula is shown as the formula (6):
wherein,
the maximum stress of each stage of cyclic load,
is as follows
The stress ratio of the stage fatigue load,
is the coefficient of sensitivity of the material to the average stress,
for the load order influencing factor to be,
the parameter is a material forgetting parameter and can be obtained by a two-stage load test.
(2) Creep load equivalent acceleration method
Aiming at the problem of damage accumulation of materials and structures under multi-stage creep load, a team of penmen conducts a large amount of research, a creep damage accumulation model suitable for constant-temperature variable-load and variable-temperature variable-load conditions is provided, and a creep load equivalent acceleration method is provided based on the creep damage accumulation model.
According to the previous research result, the non-linear damage accumulation effect exists in the creep load, and a creep load non-linear damage accumulation model is established according to the non-linear damage accumulation effect, as shown in (7):
wherein, creep damage influence index between load stages
As shown in (8):
wherein,
the relevant parameter of the GH4169 material is 0.288 calculated by the variable load creep test result as the creep endurance limit parameter,
is a first
The load of the stage creep is such that,
is a first
Tensile strength of material at creep load temperature, tensile strength at 650 DEG C
；
Is at the first
Creep life of a material/structure under a grade creep load (stress/temperature) condition can be obtained by creep testing or calculation of the endurance equation (L-M).
S4: accelerating the compilation of a task test chart;
the aircraft engine acceleration task trial run spectrum adopts slow-maximum-slow vehicle to simulate the actual random flight load spectrum, so the following parameters need to be determined in the process of compiling the acceleration task trial run spectrum: (1) slow-max-slow cycle number; (2) duration of slow vehicle state and maximum state; and (3) switching speed between slow vehicle and maximum state.
Because the takeoff section and the landing section in the aeroengine load spectrum are generally deterministic task loads, in order to keep consistent with the actual flight spectrum, the takeoff and landing load characteristics of the original load spectrum are reserved in the process of preparing the acceleration task trial run spectrum, and only the middle flight section is subjected to equivalent acceleration. The specific operation is as follows:
(1) Slow-max-slow cycle number determination
The method for accelerating the sub-cycle load is characterized in that the damage caused by the sub-cycle is calculated by using a fatigue damage accumulation model, and the damage is converted into a slow vehicle-maximum-slow vehicle cycle according to a damage equivalent principle. The number of slow-max-slow cycles after acceleration can be determined by equation (9):
wherein,
for the fatigue damage caused by each level of circulation,
the number of sub-loop levels is,
damage caused by a single slow-max-slow cycle.
According to the material data of GH4169 material given in the handbook of aviation materials, 2 nd volume of deformed superalloy casting superalloy, S-N curves of the GH4169 material at different stress ratios of 650 ℃ are determined, and fatigue damage under different types of cycles can be determined by combining the data with life curves of fatigue and the like. And finally converting to obtain 14.09 slow turning-maximum-slow turning cycles according to the damage equivalence principle, and obtaining 14 slow turning-maximum-slow turning cycles after rounding.
(2) Maximum and slow vehicle state load retention time determination
The maximum state in the accelerated task trial spectrum is divided into two parts, namely an initial maximum state and a maximum state in a slow vehicle-maximum-slow vehicle circulating process, and the sum of the two parts is equal to the duration time of the maximum state after equivalent acceleration.
Under the action of multi-stage variable-load creep load, when the load state changes, creep recovery and primary creep regeneration phenomena (PCR phenomena) can be generated, the creep recovery is related to the PCR phenomena, the size level of the load state and the load retention time of each load state, and the service life of the aircraft engine is obviously influenced. Therefore, in order to ensure that the creep recovery caused by the acceleration spectrum and the original spectrum is consistent with the PCR effect, the load-holding time of the slow-driving state and the maximum state should be the same as the long-term life test-run spectrum. The distribution of the maximum state and the slow-moving state of the long-term life test run spectrum are shown in fig. 9 and fig. 10, and the mean values are 72s and 31.5s respectively.
According to the low-power load state needing acceleration given in table 2, the creep damage calculation is performed by using equation (7), and the duration of the acceleration load in the maximum state is obtained by equivalently accelerating the creep damage to the maximum state. With equivalent acceleration of the damage, the total time to obtain the maximum state is 1923.5s, minus the maximum state duration contained in the 14 slow-max-slow cycle, and the collective maximum state duration is 914.7s.
(3) Accelerated task test chart compilation
After obtaining the load characteristics after acceleration, keeping the change rule of the rotating speed spectrum in the starting stage and the stopping stage unchanged, compiling the spectrum in the middle stage after acceleration, leading the centralized maximum state, wherein the average time of the maximum state and the slow state in 14 slow vehicle-maximum-slow vehicle cycles is respectively 72s and 31.5s, the average time of the acceleration stage and the deceleration stage is respectively 25.1s and 23.5s, finally compiling the obtained acceleration task test run spectrum as shown in fig. 11, comparing the obtained acceleration task test run spectrum with the long-term life test run spectrum as shown in fig. 12, and the acceleration coefficient is 1.73.
The method specifically comprises the following operation of detecting the damage consistency of the accelerated task test chart and the long-term service life test chart:
and carrying out fatigue-creep tests by using the GH4169 smooth sample respectively aiming at the long-term life test run spectrum and the compiled acceleration task test run spectrum. The test piece is shown in FIG. 13, with a gauge length of 25mm and a diameter of 5mm. The test is carried out on a QBR-100 type spectrum load creep testing machine, and the deformation of a test piece is recorded in real time through a Heideham grating ruler in the test process. Finally, the numbers of fracture cycles under two spectra are obtained, and the test results are shown in table 3;
the number of complete test run spectrums experienced by the smooth sample before fracture under the action of the long test spectrum is respectively 20, 21 and 20, the number of complete test run spectrums experienced before fracture under the action of the accelerated spectrum is respectively 18, 22 and 18, and finally fracture occurs in the corresponding cycle process of the next test run spectrum.
The maximum creep strain of each cycle is taken, and the creep deformation of the sample is plotted along with the cycle number of the test run spectrum, and as shown in FIG. 14, the plastic deformation of the sample gradually increases along with the increase of the cycle number of the test run spectrum. The plastic deformation increment of the sample under the first complete test run spectrum cycle is obviously larger than the plastic deformation of the sample under the latter test run spectrum cycles; the plastic deformation is uniformly increased under the action of a plurality of subsequent test run spectrums, and the strain rate is gradually reduced and tends to be stable; with the further increase of the cycle number, the strain rate is transited from a steady state to a non-steady state, the plastic deformation amount is rapidly increased, and finally, the fracture of the test piece is generated, and the characteristic is similar to the characteristic of a creep curve. The average cycle fracture times of the long test spectrum is 21.33 times as can be seen by comparing the cycle fracture times of the test spectrum; the mean number of cycles of break in the acceleration spectrum was 20.33. The error of the average cycle fracture times of the sample under the action of the long test spectrum and the acceleration spectrum is-4.69%, and the damage of the programmed acceleration task test spectrum is equivalent to that of the long-term life test spectrum.
The above embodiments are only for illustrating the technical solutions of the present invention and not for limiting the same, and although the present invention is described in detail with reference to the above embodiments, those of ordinary skill in the art should understand that: modifications and equivalents may be made to the embodiments of the invention without departing from the spirit and scope of the invention, which is to be covered by the claims.
Claims (7)
1. An aircraft engine acceleration task test chart compiling method based on damage equivalence is characterized by comprising the following steps: the method comprises the following steps:
s1, carrying out stage division on a long-life test run spectrum, wherein the long-life test run spectrum is divided into a starting section, a middle section and an ending section;
s2, carrying out load characteristic analysis on the middle section of the long-life test run spectrum, and extracting load characteristic information, wherein the load characteristic information comprises a secondary cycle, load-holding state duration and throttle lever switching rate;
s3, selecting a fatigue damage accumulation model to perform equivalent acceleration on the secondary cycle load, and selecting a creep damage accumulation model to perform equivalent acceleration on the duration time of the load-holding state;
and S4, arranging the accelerated load spectrum by combining the load characteristic information of the long-term life test spectrum to obtain an accelerated task test spectrum.
2. The method for compiling the trial run spectrum of the acceleration task of the aero-engine based on the damage equivalence as claimed in claim 1, wherein the method comprises the following steps: and the first and the last maximum state points in the S1 are used as marks for distinguishing a starting section, a middle section and an ending section.
3. The method for compiling the trial run spectrum of the acceleration task of the aero-engine based on damage equivalence as claimed in claim 1, wherein the method comprises the following steps: the S2 specifically comprises:
s2.1, extracting the number of secondary cycles including slow vehicle-maximum-slow vehicle, cruise-maximum-cruise, cruise-military push-cruise, slow vehicle-cruise-slow vehicle, military push-maximum-military push and the like by using a rain flow counting method;
s2.2, identifying the load-holding state by using the fluctuation of the rotating speed within a small range not exceeding 3 percent, counting the duration time of different load-holding states, analyzing the duration time of the maximum state and the duration time of the slow vehicle state in the circulation process, and obtaining the mean value of the duration time of the maximum state
Mean of duration of slow vehicle condition
S2.3, respectively counting the change rate of the rotating speed of the throttle rod in the acceleration and deceleration processes, and analyzing the distribution characteristics and the average value of the average change rate of the rotating speed in the acceleration stage
Mean rate of change of speed in deceleration phase
4. The method for compiling the aircraft engine acceleration task trial run spectrum based on the damage equivalence is characterized by comprising the following steps of: s3 specifically comprises the following steps:
s3.1, the fatigue damage accumulation model comprises but is not limited to a linear damage accumulation model and a nonlinear damage accumulation model based on an S-N curve, the sum of damages caused by each stage of circulation is calculated by using the fatigue damage accumulation model, then the fatigue damage is equivalent to a slow vehicle-maximum-slow vehicle circulation according to a damage equivalent principle, and the number of cycles after the equivalence is calculated as:
wherein m is a number of sub-circulation stages,
to calculate the damage of the i-th cycle obtained using the fatigue damage accumulation model,
damage caused by one slow-max-slow cycle.
S3.2, the creep damage accumulation model comprises but is not limited to a linear creep damage accumulation model and a non-linear creep damage accumulation model based on a time fraction method, the sum of creep damage caused by each stage of load-holding state is calculated by using the creep damage accumulation model, then creep damage caused by each stage of load-holding state is equivalently accelerated to be in a maximum state according to a damage equivalence principle, and the time after the equivalent acceleration is calculated as:
wherein p is the total stage number of each load-holding state in the long-term life test run spectrum,
q is the total number of slow-speed vehicle states in a long-term life test spectrum,
for the creep damage of the kth slow vehicle state calculated using the creep damage accumulation model,
the creep damage is the maximum state creep damage per unit time calculated by using a creep damage accumulation model.
5. The method for compiling the aircraft engine acceleration task trial run spectrum based on the damage equivalence is characterized by comprising the following steps of: the S4 specifically includes:
s4.1, determining an initial section and an end section of the accelerated task trial spectrum;
s4.2, arranging a slow vehicle-maximum-slow vehicle cycle;
s4.3, arranging the maximum state duration.
6. The method for compiling the trial run spectrum of the acceleration task of the aero-engine based on damage equivalence as claimed in claim 5, wherein the method comprises the following steps: s4.2 is specifically operative to: arranging total N I-Mx-I Individual slow-max-slow cycle, wherein slow state duration in a cycle is taken as the sub-cycle average slow-start duration in the long-term life test run spectrum
Maximum state duration in cycle is taken as the average maximum state duration of the secondary cycle in the long-term life test run spectrum
Duration of acceleration phase
Calculating the average rotating speed change rate of the acceleration stage in the long-term service life test run spectrum according to the following formula:
duration of deceleration phase
Calculated from the following formula:
wherein n is max At maximum state speed, n Idle The rotating speed is in a slow vehicle state.
7. The method for compiling the aircraft engine acceleration task trial run spectrum based on the damage equivalence is characterized by comprising the following steps of: s4.3 the maximum state duration is divided into two parts, the central maximum state phase and the maximum state phase contained in the slow-slow cycle, wherein the duration t of the central maximum state phase max,con Calculated from the formula:
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210880296.5A CN115640666B (en) | 2022-07-25 | 2022-07-25 | Aero-engine acceleration task test chart compiling method based on damage equivalence |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210880296.5A CN115640666B (en) | 2022-07-25 | 2022-07-25 | Aero-engine acceleration task test chart compiling method based on damage equivalence |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN115640666A true CN115640666A (en) | 2023-01-24 |
| CN115640666B CN115640666B (en) | 2023-03-28 |
Family
ID=84940480
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202210880296.5A Active CN115640666B (en) | 2022-07-25 | 2022-07-25 | Aero-engine acceleration task test chart compiling method based on damage equivalence |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN115640666B (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115994477A (en) * | 2023-03-24 | 2023-04-21 | 西安航天动力研究所 | Method for determining service life of rocket engine pipeline |
| CN116818292A (en) * | 2023-06-01 | 2023-09-29 | 南京航空航天大学 | Method for determining safe landing times of aero-engine |
| CN117330319A (en) * | 2023-08-31 | 2024-01-02 | 南京航空航天大学 | Method for monitoring damage of whole engine life test run structure of small turboshaft engine |
| CN117421900A (en) * | 2023-10-24 | 2024-01-19 | 南京航空航天大学 | Aeroengine comprehensive task spectrum compiling method considering total inlet temperature and total inlet pressure |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107247002A (en) * | 2017-04-20 | 2017-10-13 | 北京航空航天大学 | Consider the turbine rotor blade accelerated life test load design method of flight damage |
| CN110595709A (en) * | 2019-08-14 | 2019-12-20 | 南京航空航天大学 | Method for determining allowable amplitude of turbine engine blade |
| CN111507038A (en) * | 2020-04-22 | 2020-08-07 | 南京航空航天大学 | Fatigue life prediction method for ceramic matrix composite structure |
| CN112507457A (en) * | 2020-12-09 | 2021-03-16 | 中国人民解放军海军航空大学青岛校区 | Method for evaluating calendar life of airplane structure |
| WO2021227925A1 (en) * | 2020-05-09 | 2021-11-18 | 清华大学 | Notched member fatigue life prediction method and prediction apparatus based on primary load mode |
| US20220026326A1 (en) * | 2019-01-11 | 2022-01-27 | East China University Of Science And Technology | A Multiaxial Creep-Fatigue Prediction Method Based On ABAQUS |
-
2022
- 2022-07-25 CN CN202210880296.5A patent/CN115640666B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107247002A (en) * | 2017-04-20 | 2017-10-13 | 北京航空航天大学 | Consider the turbine rotor blade accelerated life test load design method of flight damage |
| US20220026326A1 (en) * | 2019-01-11 | 2022-01-27 | East China University Of Science And Technology | A Multiaxial Creep-Fatigue Prediction Method Based On ABAQUS |
| CN110595709A (en) * | 2019-08-14 | 2019-12-20 | 南京航空航天大学 | Method for determining allowable amplitude of turbine engine blade |
| CN111507038A (en) * | 2020-04-22 | 2020-08-07 | 南京航空航天大学 | Fatigue life prediction method for ceramic matrix composite structure |
| WO2021227925A1 (en) * | 2020-05-09 | 2021-11-18 | 清华大学 | Notched member fatigue life prediction method and prediction apparatus based on primary load mode |
| CN112507457A (en) * | 2020-12-09 | 2021-03-16 | 中国人民解放军海军航空大学青岛校区 | Method for evaluating calendar life of airplane structure |
Non-Patent Citations (3)
| Title |
|---|
| GUOFA LI; HONGXIANG ZHU; XINGE ZHANG; JIALONG HE; XINYUE ZHAO: "Compilation of Program Loading Spectrum for CNC Lathe’s Feed System Based on Two-dimensional Kernel Function" * |
| 肖阳;徐可君;秦海勤;贾明明;: "基于疲劳-蠕变载荷等效转换的涡轮盘载荷谱编制及寿命预测" * |
| 费斌军，熊峻江，高镇同，剡鸿甲: "疲劳／断裂加速试验载荷谱的编制及其实验研究" * |
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115994477A (en) * | 2023-03-24 | 2023-04-21 | 西安航天动力研究所 | Method for determining service life of rocket engine pipeline |
| CN116818292A (en) * | 2023-06-01 | 2023-09-29 | 南京航空航天大学 | Method for determining safe landing times of aero-engine |
| CN116818292B (en) * | 2023-06-01 | 2024-02-23 | 南京航空航天大学 | Method for determining safe landing times of aero-engine |
| CN117330319A (en) * | 2023-08-31 | 2024-01-02 | 南京航空航天大学 | Method for monitoring damage of whole engine life test run structure of small turboshaft engine |
| CN117330319B (en) * | 2023-08-31 | 2024-04-02 | 南京航空航天大学 | Method for monitoring damage of whole engine life test run structure of small turboshaft engine |
| CN117421900A (en) * | 2023-10-24 | 2024-01-19 | 南京航空航天大学 | Aeroengine comprehensive task spectrum compiling method considering total inlet temperature and total inlet pressure |
| CN117421900B (en) * | 2023-10-24 | 2024-05-14 | 南京航空航天大学 | Aeroengine comprehensive task spectrum compiling method considering total inlet temperature and total inlet pressure |
Also Published As
| Publication number | Publication date |
|---|---|
| CN115640666B (en) | 2023-03-28 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN115640666B (en) | Aero-engine acceleration task test chart compiling method based on damage equivalence | |
| CN109033709B (en) | Component fatigue life evaluation method based on nonlinear fatigue damage accumulation theory | |
| CN107145641B (en) | Blade vibration fatigue probability life prediction method | |
| CN114544177B (en) | Core machine durability test method for typical use state of engine complete machine | |
| CN106644490A (en) | Method for predicting high-low-cycle composite fatigue crack growth life of turbine joggle structure | |
| KR102154163B1 (en) | Scheduling of inspections on machine components and prediction of end of life | |
| CN111507038B (en) | Fatigue life prediction method for ceramic matrix composite structure | |
| CN107122531A (en) | A kind of quick runner lifetime estimation method based on accelerated life test | |
| CN112730117B (en) | Temperature-changing and load-changing creep equivalent acceleration spectrum compiling method | |
| CN115795744B (en) | Method for compiling aviation turbofan engine component level low-cycle fatigue life load spectrum | |
| CN115168990B (en) | Method for determining typical transient course spectrum of aero-engine | |
| KR20220146942A (en) | System and method for turbine blades testing | |
| CN111795901A (en) | Test method for simulating service damage of turbine blade material | |
| CN114354200B (en) | Vibration load spectrum compiling method of aeroengine control system | |
| CN116542114B (en) | Method and device for analyzing temperature stress deformation of compressor rotor based on overall parameters | |
| CN116050202B (en) | Chaboche blade fatigue life prediction model and method suitable for various average stress performances | |
| CN115859795A (en) | Acceleration task test load spectrum compilation method considering heating and pressurizing | |
| CN110646205A (en) | Acceleration equivalent test method for long-life aircraft engine | |
| Moneta et al. | Influence of manufacturing tolerances on vibration frequencies of turbine blade | |
| CN115406664A (en) | Method and system for compiling turbo-propeller engine acceleration task trial spectrum | |
| CN114139276A (en) | Fatigue life analysis method for disk-shaft integrated blisk structure | |
| CN110987388B (en) | Method for equivalent machining notch based on notch fatigue strength | |
| CN107941481A (en) | A kind of high-temperature duration life assessment method of vehicle supercharger turbine | |
| Inozemtsev et al. | Life validation strategy | |
| Sorenson et al. | Low-cycle fatigue in small turbines: Low-cycle fatigue is discussed and is the basis for explaining a compressor-rotor failure which occurred during the development of a turbojet engine |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |