CN113484020B - A thermodynamic coupling test device for simulating aero-engine high temperature service environment - Google Patents

Abstract

The invention discloses a thermodynamic coupling test device for simulating a high-temperature service environment of an aircraft engine, which relates to the technical field of thermal barrier coating service environment test devices and comprises a test bench, wherein a heating component, a cooling component and a force application component for fixing two ends of a workpiece and applying axial force to the workpiece are arranged on the test bench; the workpiece is fixed on the force application assembly, then the heating end of the heating assembly is aligned to the heating surface of the workpiece to be heated, and the cooling port of the cooling assembly is aligned to the cooling surface of the workpiece to be cooled, so that a temperature gradient can be formed between the heating surface and the cooling surface of the workpiece, and meanwhile, the force application assembly is utilized to apply alternating stress to the workpiece, so that the service environment of an actual aircraft engine can be fully simulated, and the accurate failure process of the thermal barrier coating in the high temperature gradient and alternating stress state can be obtained.

Description

A thermodynamic coupling test device for simulating aero-engine high-temperature service environment

technical field

The invention relates to the technical field of a thermal barrier coating service environment test device, in particular to a thermodynamic coupling test device for simulating a high-temperature service environment of an aero-engine.

Background technique

Aero-engines have always been known as "the jewel in the crown", and their development level represents a country's comprehensive scientific and technological level and national defense strength. The thrust-to-weight ratio of an aero-engine is one of the important indicators to measure the performance of the engine, which is closely related to the maneuverability and economy of the aircraft. According to the principle of Carnot cycle, increasing the intake air temperature before the turbine is the most important and practical method to improve the engine thrust-weight ratio. At present, there are three commonly used methods to increase the temperature of the intake air before the turbine: the development of new high-temperature structural materials, the film cooling technology and the thermal barrier coating technology. At present, the development of traditional single crystal superalloy and gas film cooling technology has approached the limit of materials and processes. Thermal barrier coating technology and the development of new high-temperature structural materials have become more feasible methods to further increase the temperature before the turbine.

The working environment of aero-engines is extremely complex and harsh, including more than 20 kinds of loads such as high temperature, stress, and corrosive environment. Studies have shown that high temperature oxidation, ablation, thermal expansion mismatch, particle erosion, corrosion of corrosive substances, etc. are the main reasons for the failure of thermal barrier coatings. Premature failure caused by various reasons is a key bottleneck restricting the application and development of thermal barrier coatings and new high-temperature structural materials. Therefore, a simulation platform for engine service environment is established to analyze the failure mechanism of thermal barrier coatings and high-temperature structural materials under various conditions. In-depth research is the only way to improve and develop thermal barrier coatings and high-temperature structural materials.

At present, some aero-engine service environment simulation work has been carried out at home and abroad, mainly including the simulation of coating thermal cycle, thermal gradient, corrosion environment and thermal, mechanical and environmental coupling environment. For example, the application number is "201510033169.1" and the invention patent named "Thermal Shock Life Evaluation Test Device for Thermal Barrier Coatings" proposes a thermal barrier coating of an oxypropane gas heating gun in high temperature, thermal gradient and CMAS coupled service environment. Thermal shock test device; the application number is "200610024973.4" and the invention patent named "Thermal Barrier Coating Thermal Shock Resistance Test Device" in the heat source installation system can install different heat sources, and adjust the heat source and the sample by adjusting the distance between the heat source and the sample. The cooling medium input port is fixed at the lower part of the bracket, and different cooling medium can be connected to the sample to cool the sample, so as to realize the cyclic heating of the sample. However, none of the above-mentioned devices formed a temperature gradient inside the sample, which caused the simulated working environment to be far from the actual working environment of the aero-engine, and the failure process of the thermal barrier coating was also inaccurate.

Therefore, to provide a complex thermomechanical coupling simulation device that can realize high temperature gradient and alternating stress state is of great scientific and engineering significance for in-depth study of the failure mechanism of thermal barrier coatings and new high-temperature structural materials.

SUMMARY OF THE INVENTION

The purpose of the present invention is to provide a thermodynamic coupling test device for simulating the high-temperature service environment of aero-engine, so as to solve the problems existing in the above-mentioned prior art, and can fully simulate the service environment of the actual aero-engine and obtain the thermal barrier coating at this high temperature. Change failure process under gradient and alternating stress state, so that the failure analysis of thermal barrier coating is more accurate.

In order to achieve the above purpose, the present invention provides the following scheme: the present invention provides a thermodynamic coupling test device for simulating a high-temperature service environment of an aero-engine, including a test bench, on which a heating assembly, a cooling assembly and a device for fixing are provided. The two ends of the workpiece are used for applying axial force to the workpiece. The workpiece includes a heating surface and a cooling surface. The heating component is used for heating the heating surface of the workpiece, and the cooling component is used for cooling the cooling surface.

Preferably, a heat insulating plate is arranged between the heating component and the force applying component to prevent the force applying component from being heated, a gap is formed on the heat insulating plate, and the heating flame of the heating component penetrates through The notch heats the heating surface of the workpiece.

Preferably, two blocking pieces are slidably arranged at the notch, and the size of the notch is adjusted by changing the relative positions of the two blocking pieces.

Preferably, the heat insulation plate has a cavity inside, and both ends of the heat insulation plate respectively have an inlet and an outlet that communicate with the cavity, and the inlet communicates with the medium supply part in the cooling assembly, so The outlet is communicated with the pipeline, and the medium acts on the cooling surface of the workpiece through the pipeline.

Preferably, the medium supply part is an air pump.

Preferably, a movable baffle is provided on the test table, and the movable baffle can move to between the heating end and the gap to shield the gap.

Preferably, the movable baffle is rotatably fixed on the bottom of the heat shield.

Preferably, a first sliding table and a second sliding table are also arranged perpendicular to each other on the experimental table, the heating assembly includes a base and a heating body slidably arranged on the base, and the base slides It is arranged on the first sliding table, and the sliding direction of the heating body is perpendicular to the sliding direction of the base; the second sliding table is also provided with a vertical track, and the force applying component is slidably arranged on on the vertical track.

Preferably, the heating component is a plasma heater.

The invention provides a thermodynamic coupling test method for simulating a high-temperature service environment of an aero-engine, comprising the following steps:

1) Fix the workpiece on the force-applying component, and adjust the size of the gap on the heat shield according to the size of the workpiece, and adjust the positions of the heating component and the force-applying component so that the heating end, the gap and the workpiece are on the same straight line;

2) Start the heating component to heat the workpiece, and at the same time use the first ventilation line or the second ventilation line to cool the workpiece, so that a temperature gradient is formed inside the workpiece, and the axial force is applied to the workpiece through the force application component, and the tensile force is used. The sensor and thermocouple measure the tensile force and temperature gradient distribution of the workpiece respectively;

3) When the heating time reaches the set value, the force is applied to the assembly to release the force, and the movable baffle is rotated upward to between the gap and the heating end to block the heating flame, and at the same time, the first ventilation line and the second ventilation line are used. cooling the workpiece;

4) After the workpiece cools down to room temperature, the movable baffle plate rotates downwards, evacuated from the front of the notch, and the heating end performs the next heating cycle on the workpiece.

The present invention has achieved the following technical effects with respect to the prior art:

1. In the present invention, the workpiece is fixed on the force-applying component, and then the heating end of the heating component is aligned with the heating surface of the workpiece for heating, and the cooling port of the cooling component is aligned with the cooling surface of the workpiece for cooling, so that the heating surface of the workpiece is cooled. A temperature gradient will be formed between it and the cooling surface. At the same time, the force component is used to apply alternating stress to the workpiece, which can fully simulate the service environment of the actual aero-engine and obtain the change of the thermal barrier coating under this high temperature gradient and alternating stress state. Failure process, the failure process analysis of thermal barrier coating is more accurate;

2. In the present invention, there is a cavity in the heat insulating plate. During the experiment, the cooling medium is first passed into the heat insulating plate for heating, and then acts on the cooling surface of the workpiece to simulate the cooling temperature of the actual cooling surface of the aero-engine to form a cooling medium. A more realistic temperature gradient distribution is beneficial to the accuracy of the experimental results;

3. The present invention can cool the workpiece without turning off the flame by setting the movable baffle. When the next heating cycle is performed, the workpiece can be quickly heated, which not only avoids the influence of repeated flame-off on the life of the heating component, but also The heating efficiency can be significantly improved.

Description of drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the accompanying drawings required in the embodiments will be briefly introduced below. Obviously, the drawings in the following description are only some of the present invention. In the embodiments, for those of ordinary skill in the art, other drawings can also be obtained according to these drawings without creative labor.

Fig. 1 is the overall structure schematic diagram of the present invention;

Figure 2 is a schematic structural diagram of a heating assembly;

Fig. 3 is the structural representation of heat insulation board;

Figure 4 is a schematic diagram of the back structure of the heat insulation board

Among them, 1. experimental bench; 2. heating assembly; 3. cooling assembly; 4. applying force assembly; 5. workpiece; 6. heat insulation plate; 7. notch; The first slip table; 11, the second slip table; 12, the vertical track; 13, the crawler.

Detailed ways

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. Obviously, the described embodiments are only a part of the embodiments of the present invention, but not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

The purpose of the present invention is to provide a thermodynamic coupling test device for simulating the high-temperature service environment of aero-engine, so as to solve the problems existing in the above-mentioned prior art, and can fully simulate the service environment of the actual aero-engine and obtain the thermal barrier coating at this high temperature. The change process under gradient and alternating stress state is more accurate for the analysis of the change process of the thermal barrier coating.

In order to make the above objects, features and advantages of the present invention more clearly understood, the present invention will be described in further detail below with reference to the accompanying drawings and specific embodiments.

Example 1:

As shown in FIGS. 1 to 2 , this embodiment provides a thermodynamic coupling test device for simulating a high-temperature service environment of an aero-engine, including a test bench 1, and a heating component 2, a cooling component 3 and a device for fixing The force component 4 that applies axial force to the workpiece 5 at both ends of the workpiece 5. The workpiece 5 includes a heating surface and a cooling surface. The heating component 2 is used to heat the heating surface of the workpiece 5, and the cooling component 3 is used to heat the cooling surface. Cool down.

During the experiment, first fix the two ends of the workpiece 5 on the force application component 4, set the heating parameters of the heating component 2 to the workpiece 5, and then align the heating end of the heating component 2 with the heating surface of the workpiece 5 for heating. , the cooling port of the cooling component 3 is aligned with the cooling surface of the workpiece 5 for cooling, so that a temperature gradient is formed between the heating surface and the cooling surface of the workpiece 5, while the workpiece 5 is heated, the force applying component 4 is used according to the set program. Applying alternating stress to the workpiece 5 realizes the simulation of high temperature, high heat flux density, gradient temperature and thermal coupling service environment, so that through the detection of the workpiece, the thermal barrier coating under this high temperature gradient and alternating stress state can be obtained. Therefore, the failure analysis of the thermal barrier coating in the real service environment is more accurate.

It should be noted that the workpiece 5 in this embodiment can usually be selected in a sheet shape or a cylindrical shape. The cylindrical structure is more similar to the structure of the actual aero-engine blade, and the formed temperature gradient is also closer to the actual temperature gradient formation mechanism. The manufacturing process of the sheet-like structure is simpler, and the failure process of the thermal barrier coating in the simulated service environment can also be obtained. The cooling component 3 and the workpiece 5 of different shapes cooperate in different ways. When the workpiece 5 is in the form of a sheet or sheet, one side is coated with thermal barrier coating, this side is the heating surface, the other side is the metal substrate surface, this side is the cooling surface, at this time, the cooling port in the cooling component 3 directly acts on the cooling medium It is cooled on the surface of the metal substrate; when the workpiece 5 is cylindrical, in order to fully simulate the structure of the aero-engine blade, the workpiece 5 has a cavity inside, and its outer surface is coated with a thermal barrier coating. This surface is the heating surface, and the inner surface is heated. The surface (that is, the cavity wall surface) is the surface of the metal substrate, and this surface is the cooling surface. At this time, the cooling port in the cooling component 3 passes the cooling medium into the cavity to cool the surface of the metal substrate. The cooling pipes are connected to both ends of the workpiece 5 and communicate with its inner cavity. Therefore, in order to be able to match workpieces 5 of different shapes, the cooling assembly 3 in this embodiment can be provided with two sets of cooling pipelines at the same time. The pipeline port is directly aligned with the metal base surface of the sheet workpiece 5, and valves are provided on both sets of pipelines. When in use, the corresponding cooling pipeline is selected according to the shape of the workpiece 5 for cooling.

In this embodiment, the heating component 2 can use a common plasma heater, and its heating temperature is high, which can make the workpiece 5 reach 1000°C or higher, and the heating speed is also significantly faster than that of the existing flame heater; and the plasma heater can be Carry out thermal cycle simulation under certain temperature heating gradient conditions, such as the target temperature of workpiece 5 is 1200 °C, the first stage: room temperature ~ 800 °C, adjust at high speed, allowing large overshoot; the second stage: 800 °C ~ 1100 °C , adjust at a medium speed, allowing a small overshoot; the third stage: 1100 ° C ~ 1200 ° C, adjust at a lower speed, allowing a very small overshoot; the structure of the plasma heater or other heating devices are all skilled in the art This embodiment does not describe the detailed structure of a device that is familiar to persons; similarly, the cooling component 3 is also a commonly used component in the field.

Those skilled in the art should know that a detection system is also provided in this embodiment, and the detection system includes an infrared thermometer, an infrared thermal imager, a CCD camera, etc. The infrared thermometer can detect the temperature change of the material surface in real time, and the infrared thermal imager can detect the temperature change of the material surface in real time. The change of the internal structure of the material can be known by analyzing the temperature field of the material. The CCD camera is mainly used to detect the change of the surface topography of the material. changes in the service environment. Infrared thermometers, infrared thermal imagers, CCD cameras, etc. are all commonly used detection devices in the art, and their use methods and their fixing methods on the test bench 1 are well known to those skilled in the art. Therefore, this embodiment This is not specifically limited, and the detection device is not limited to the devices listed above.

In this embodiment, it is not necessary to ensure that the surface temperature of the workpiece 5 is uniform during the experiment. For example, when the workpiece 5 is a sheet, the surface temperature of the heating surface and the temperature gradient between the heating surface and the cooling surface are relatively uniform. However, when the workpiece 5 is cylindrical, the temperature of the cylindrical surface facing the heating component 2 is relatively high, and the temperature of the cylindrical surface on the other side is relatively low. It is detected by thermal imager and other devices, and due to the uneven distribution of the surface temperature of the heating surface and its internal temperature gradient, multiple sets of thermal coupling data can be formed, which is more conducive to the study of the failure process of thermal barrier coatings.

In this embodiment, a tensioning machine can be selected for the force-applying component 4, which can provide axial tension or pressure to the workpiece 5 according to the experimental requirements, and the tensioning machine has a stress sensor on the fixture for fixing the workpiece 5, which is used to measure the force of the workpiece 5. Moreover, the fixture is a water-cooled fixture with a circulating cooling water circuit inside to prevent the fixture from overheating, and the circulating cooling water circuit of the fixture and the cooling circuit of the cooling component are independent of each other.

Since the heating temperature of the heating element 2 is relatively high, in order to prevent the force applying element 4 from being affected by the heating of the heating element 2, and also to prevent the flame on the heating surface and the cooling medium on the cooling surface from interfering with each other when the workpiece 5 is a sheet-like structure, this embodiment In the example, a heat insulating plate 6 is arranged between the heating assembly 2 and the force applying assembly 4. At the same time, in order that the heating assembly 2 can smoothly heat the workpiece 5, a gap 7 is provided on the heat insulating plate 6, and the heating flame of the heating assembly 2 penetrates through the gap. 7. The heating surface of the workpiece 5 is heated, as shown in FIGS. 3 to 4 . Those skilled in the art should understand that the function of the heat insulating plate 6 here is mainly to shield the heating flame, so that the heating flame can only heat the workpiece 5 through the gap 7, thereby reducing the heating effect of the heating component 2 on the force applying component 4 and avoiding the The overheating of the force component 4 will cause greater pressure on the water cooling of the fixture and other components, and is also unfavorable for the service life of the force component 4 , but the heat shield 6 cannot completely prevent the temperature increase of the force component 4 .

In order to adapt to workpieces 5 of different sizes, two baffles 8 are slidably arranged at the notch 7 , and the size of the notch 7 can be changed by changing the relative positions of the two baffles 8 .

In this embodiment, the heat insulating plate 6 has a cavity inside, and the two ends of the heat insulating plate 6 respectively have an inlet and an outlet that communicate with the cavity. During the process, the cooling medium is first introduced into the cavity of the heat insulation plate 6. Since the heat insulation plate 6 directly faces the heating assembly 2, under the action of the heating assembly 2, the temperature of the cooling medium will rise, and then the cooling medium will be discharged. Under the action of the pipeline, it acts on the cooling surface of the workpiece 5; the reason why the cooling medium is passed into the heat shield 6 first is because, in the actual service environment of the aero-engine, the medium entering the engine blade cavity is significantly higher than The room temperature can usually reach about 200°C, so the use of room temperature gas or liquid cannot meet the requirements of fully simulating the service environment of the aero-engine, and the cooling medium is first passed into the heat insulation plate 6 for heating, which can fully simulate the service environment and form A more realistic temperature gradient distribution is beneficial to the accuracy of the experimental results; the connection between the inlet and outlet on the heat shield 6 and the cooling assembly 3 is well known to those skilled in the art, so it is not shown in the drawings.

Specifically, in this embodiment, the medium supply part is an air pump, and the cooling circulating medium is air.

Further, in the present embodiment, a movable baffle 9 is provided on the test table 1, and the movable baffle 9 can be moved to between the heating end and the gap 7 to cover the gap 7; thus, when a heating cycle of the workpiece 5 is completed, , using the movable baffle 9 to cover the gap 7, the heating assembly 2 can be stopped to heat the workpiece 5, and the workpiece 5 can be cooled at this time to prepare for the next heating cycle. The ignition process of the heating assembly 2 is usually more complicated. Repeated flameout and ignition will reduce the service life of the heating assembly 2, and in this embodiment, by setting the movable baffle 9, the workpiece 5 can be cooled without flameout. When the next heating cycle is performed, the workpiece 5 can be quickly cooled. Heating can not only avoid the influence of repeated flameout on the life of the heating assembly 2, but also can significantly improve the heating efficiency;

It should be noted that, in this embodiment, the cooling device for the workpiece 5 after the heating is not limited, and the cooling device can be the cooling component 3 for generating a temperature gradient. Under the action of flame shielding, the cooling medium passing into the heat insulation plate 6 will not significantly increase the temperature, and the cooling assembly 3 can be used to cool the workpiece 5; Cooling, this cooling process is well known to those skilled in the art, which is not specifically limited in this embodiment.

In order to facilitate the alignment and adjustment of the positions of the heating assembly 2 and the workpiece 5, in this embodiment, a first sliding table 10 and a second sliding table 11 are also arranged on the test table 1 perpendicular to each other. The heating assembly 2 includes a base The seat and the heating body are slidably arranged on the base, the base is slidably arranged on the first sliding table 10, and the sliding direction of the heating body is perpendicular to the sliding direction of the base; the second sliding table 11 is also provided with a vertical The straight track 12, the force applying component 4 is slidably arranged on the vertical track 12, and both the heating component 2 and the force applying component 4 include several lines and pipelines. In this embodiment, the pipelines of the heating component 2 and the force applying component 4 are , and the lines are set in the crawler belt 13 to prevent them from interfering with the movement of the heating component 2 and the force applying component 4 . Both the first sliding table 10 and the second sliding table 11 include high-precision screw rods and servo motors, and the specific structures thereof are well known to those skilled in the art.

Example 2:

This embodiment provides a thermodynamic coupling test method for simulating a high-temperature service environment of an aero-engine, comprising the following steps:

1) Fix the workpiece 5 on the force application component 4, and adjust the size of the gap 7 on the heat insulation plate 6 according to the size of the workpiece 5, and adjust the positions of the heating component 2 and the force application component 4, so that the heating end, the gap 7 and the Workpiece 5 is on the same straight line;

2) Start the heating assembly 2, heat the workpiece 5, and simultaneously use the first ventilation pipeline or the second ventilation pipeline to cool the workpiece 5, so that a temperature gradient is formed inside the workpiece 5, and the workpiece 5 is subjected to a shaft through the force application component 4. The tensile force and the temperature gradient distribution of the workpiece 5 are respectively measured by the tensile force sensor and the thermocouple;

3) When the heating time reaches the set value, the force applying component 4 is unloaded, and at the same time, the movable baffle plate 9 is rotated upward to between the gap 7 and the heating end to block the heating flame, and at the same time, the first ventilation line and the second ventilation pipe are used. The ventilation pipeline cools the workpiece 5;

4) After the workpiece 5 is cooled to room temperature, the movable baffle plate 9 is rotated downwards, evacuated from the front of the notch 7, and the heating end performs the next heating cycle on the workpiece 5.

Adaptive changes made according to actual needs are all within the protection scope of the present invention.

It should be noted that it is obvious to those skilled in the art that the present invention is not limited to the details of the above-mentioned exemplary embodiments, and the present invention can be implemented in other specific forms without departing from the spirit or essential characteristics of the present invention. . Therefore, the embodiments are to be regarded in all respects as illustrative and not restrictive, and the scope of the invention is to be defined by the appended claims rather than the foregoing description, which are therefore intended to fall within the scope of the claims. All changes within the meaning and range of the equivalents of , are included in the present invention. Any reference signs in the claims shall not be construed as limiting the involved claim.

Claims (6)

1. a thermodynamic coupling test device simulating aero-engine high-temperature service environment, is characterized in that, comprises test bench, and described test bench is provided with heating assembly, cooling assembly and for fixing both ends of workpiece, and applying shaft to workpiece A force applying component, the workpiece includes a heating surface and a cooling surface, the heating component is used for heating the heating surface of the workpiece, and the cooling component is used for cooling the cooling surface; A heat shield is arranged between the heating component and the force applying component to prevent the force applying component from being heated, a gap is provided on the heat shield, and the heating flame of the heating component passes through the gap The heating surface of the workpiece is heated; two baffles are slidably arranged at the gap, and the size of the gap is adjusted by changing the relative positions of the two baffles; The heat insulation plate has a cavity inside, and the two ends of the heat insulation plate respectively have an inlet and an outlet that communicate with the cavity, the inlet is communicated with the medium supply part in the cooling assembly, and the outlet is connected to the cavity. The pipeline is connected, and the medium acts on the cooling surface of the workpiece through the pipeline. 2 . The thermodynamic coupling test device for simulating a high-temperature service environment of an aero-engine according to claim 1 , wherein the medium supply part is an air pump. 3 . 3. The thermodynamic coupling test device for simulating the high-temperature service environment of an aero-engine according to claim 1 or 2, wherein a movable baffle is provided on the test bench, and the movable baffle can be moved to the heating end Between the gap and the gap, the gap is shielded. 4 . The thermodynamic coupling test device for simulating the high-temperature service environment of an aero-engine according to claim 3 , wherein the movable baffle is rotatably fixed on the bottom of the heat shield. 5 . 5. The thermodynamic coupling test device for simulating the high-temperature service environment of an aero-engine according to claim 1, wherein the test platform is also provided with a first sliding table and a second sliding table perpendicular to each other. The heating assembly includes a base and a heating body slidably arranged on the base, the base is slidably arranged on the first sliding table, and the sliding direction of the heating body is perpendicular to the sliding direction of the base; A vertical rail is also arranged on the second sliding table, and the force applying component is slidably arranged on the vertical rail. 6 . The thermodynamic coupling test device for simulating the high-temperature service environment of an aero-engine according to claim 1 , wherein the heating component is a plasma heater. 7 .

Images