Test blade for aeroengine blade containment test

Abstract

The present application relates to a kind of test blade for aero-engine blade containment test, test blade includes: blade (1);Guide groove (4), along the surface of blade (1) extends;Detonator groove (5), along the surface of blade (1) extends, and is communicated with guide groove (4);Explosive device (6) is arranged in guide groove (4);Detonator (7) is arranged in detonator groove (5) and is connected with explosive device (6);And sheet-like connecting piece (8), cover is set on guide groove (4) and / or detonator groove (5), the two ends of sheet-like component (8) in the width direction of guide groove (4) are respectively connected with the two side blades (1) of guide groove (4) and / or detonator groove (5), improve the problem that explosive quantity is large in the related art and is prone to cause secondary accident.

Description

Technical Field

[0001] This invention relates to the field of aero-engine testing, and more specifically, to a test blade for aero-engine blade containment testing. Background Technology

[0002] During the operation of an aero-turbine engine, the detachment of a high-speed rotating blade from the rotor poses a significant threat to personnel and property safety. On one hand, the ejected high-speed, high-energy debris possesses extremely strong penetrating power, threatening personnel, equipment, fuel lines, and electrical circuits. On the other hand, the loss of a blade causes a massive imbalance in the entire rotor; continued rotation in this unbalanced state can render the entire turbine engine unusable, and the resulting secondary damage severely threatens flight safety. Therefore, before any aero-turbine engine is put into formal use, a blade containment test must be conducted to verify the engine casing's ability to contain high-speed ejected blades and withstand corresponding unbalanced loads.

[0003] Enclosure tests of aero-turbine engine blades require strict control over the timing of blade separation, releasing the specified blade section at a specified speed, position, and location. The corresponding release technique is a crucial factor determining the success or failure of the test. Currently, there are three commonly used release methods.

[0004] The first method is the pre-defect method. This method artificially creates defects (such as cracks, through-grooves, holes, etc.) at designated locations on the test piece. Due to the centrifugal load of the blade, the pre-created defects expand at a certain rotor speed, eventually causing the connection to fracture and fail, releasing the blade. This method is simple to operate and has low risk; however, due to factors such as uneven material properties on the fracture surface, local material defects, manufacturing tolerances, and stress concentration, the control precision for the blade release timing is poor, making it difficult to meet the requirements of complex structures and high-precision tests.

[0005] The second method is the heat-fly separation method. This method is based on the principle that the mechanical properties of metallic materials decrease with increasing temperature. Heaters are pre-embedded in specific parts of the blade. During the test, after the rotor reaches a predetermined speed, the heaters are activated to heat the blade. The local temperature of the blade rises, and the material properties decrease. After continuous heating for a period of time, the blade separates under the action of centrifugal force. This technology has a very narrow scope of application, suitable only for blades made of specific metal materials. Furthermore, because it requires continuous heating, the interval between activating the heater and blade separation is relatively long, making it difficult to accurately control the timing of blade separation.

[0006] The third method is the explosive fly-off method. This method involves placing an explosive (such as a shaped-jet cutter) at a designated location on the blade, igniting the explosive at a specified release speed, and using the energy generated by the explosion to cut the blade and make it fly off. This method has a high degree of control over the release timing and is the mainstream method internationally. However, this method currently has the following disadvantages: (1) The explosive charge is large, and the energy generated by the explosion will affect the normal operation of other components, especially the rotor shaft system. Moreover, the explosion process is very dangerous and can easily cause secondary accidents; (2) The structure is complex and the installation is difficult. During the test, the explosive may be thrown out by the centrifugal load, causing the test to fail. In addition, with the development of aero-turbine engine technology, the aerodynamic shape design and materials used for blades have become increasingly complex. As a result, the separation section is no longer the traditional straight section, but an arc section with an airfoil (such as the flow channel section of a fan blade). The design and material properties that are very different from the traditional ones pose new challenges to the blade release method. Summary of the Invention

[0007] The present invention aims to provide a test blade for containment testing of aero-engine blades, in order to improve the problem in related technologies where the large amount of explosives can easily cause secondary accidents.

[0008] According to one aspect of the present invention, a test blade for an aero-engine blade containment test is provided, the test blade comprising:

[0009] blade;

[0010] Guide grooves extend along the surface of the blade;

[0011] The detonator groove extends along the surface of the blade and is connected to the guide groove;

[0012] The explosive device is housed in a guide groove;

[0013] Detonator, located in a detonator slot and connected to the explosive device; and

[0014] A sheet-like connector is installed on the guide groove and / or detonator groove, with both ends of the sheet-like component along the width direction of the guide groove connected to the blades on both sides of the guide groove and / or detonator groove, respectively.

[0015] In some embodiments, the sheet connector extends along the guide groove and / or detonator groove.

[0016] In some embodiments, the sheet connector is bonded to the blade.

[0017] In some embodiments, the sheet connector is made of metal.

[0018] In some embodiments, the blade edge is provided with a metal edging, and the guide groove and / or detonator groove passes through the metal edging.

[0019] In some embodiments, the surface of the blade is curved.

[0020] In some embodiments, guide grooves and detonator grooves are provided on two opposing surfaces of the blade. The guide grooves on the two surfaces of the blade are respectively provided with explosive devices, and the detonator grooves on the two surfaces of the blade are respectively provided with detonators. The detonators are connected to the explosive devices located on the same surface of the blade.

[0021] In some embodiments, two detonators located on two surfaces of the blade are connected to the same detonation controller and are detonated simultaneously by the detonation controller.

[0022] In some embodiments, the explosive device includes a detonating cord.

[0023] In some embodiments, the guide groove and the detonator groove are arranged side by side along the flow channel line cross section and both extend along the flow channel line cross section.

[0024] Applying the technical solution of this invention, after the explosive device is detonated by a detonator, the explosive energy acts on the plate-shaped connector. Under the inertial reaction of the plate-shaped connector, the explosive energy is directed to the thickness direction of the blade, producing a cutting effect. Due to the inertial constraint effect of the plate-shaped connector, the airfoil section is cut off. This structure can reduce the amount of explosive used, has high reliability, and the plate-shaped connector has virtually no impact on the airfoil and minimal impact on adjacent structures.

[0025] Other features and advantages of the invention will become clear from the following detailed description of exemplary embodiments of the invention with reference to the accompanying drawings. Attached Figure Description

[0026] To more clearly illustrate the technical solutions in the embodiments of the present invention or related technologies, the drawings used in the description of the embodiments or related technologies will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0027] Figure 1 A schematic diagram of the structure of an aero-engine blade according to an embodiment of the present invention is shown;

[0028] Figure 2 A schematic diagram of the flow channel cross-section of an aero-engine blade according to an embodiment of the present invention is shown;

[0029] Figure 3 A schematic diagram of the test blade structure for an aero-engine blade containment test according to an embodiment of the present invention is shown.

[0030] Figure 4 It shows Figure 3A magnified view of a section at point E in the middle;

[0031] Figure 5 A schematic diagram of the cross-sectional structure of a test blade used for containment testing of an aero-engine blade according to an embodiment of the present invention is shown.

[0032] Figure 6 It shows Figure 3 A schematic diagram of the cross-sectional structure at point BB; and

[0033] Figure 7 It shows Figure 6 A magnified view of a section at point F. Detailed Implementation

[0034] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the present invention or its application or use. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0035] Figure 1 A schematic diagram of the structure of an aero-engine blade is shown, such as... Figure 1 As shown, the blade has a leading-edge metal edging 2 and a flow channel section 3. Civil aviation airworthiness regulations clearly require that, during containment testing, blade 1 should break apart along the flow channel section 3. Figure 2 A schematic diagram of the flow channel section 3 of an aero-engine blade is shown.

[0036] Blades are independent components that form the aerodynamic flow path of an aero-turbine engine, responsible for converting internal and kinetic energy of air. Enclosure tests are used to assess the structural resilience of an aero-turbine engine to damage caused by blade fracture. During the test, specific release techniques are used to detach the blade from the rotor within a specified speed range.

[0037] Explosive fly-off is a release method that uses explosive energy to instantaneously cut the blade cross section during containment testing, causing it to separate and fly out.

[0038] Figure 3 This embodiment shows a schematic diagram of the structure of a test blade used for containment testing of an aero-engine blade with an explosive breakage structure. Figure 4 It shows Figure 3 A magnified view of a section at point E in the middle.

[0039] Combination Figures 3 to 7As shown, the test blade used for the containment test of an aero-engine blade includes a blade 1, a guide groove 4, a detonator groove 5, an explosive device 6, and a detonator 7. The guide groove 4 extends along the surface of the blade 1; the detonator groove 5 extends along the surface of the blade 1 and is connected to the guide groove 4; the explosive device 6 is disposed in the guide groove 4; the detonator 7 is disposed in the detonator groove 5 and is connected to the explosive device 6; a sheet-like connector 8 is disposed on the guide groove 4 and / or the detonator groove 5, and the two ends of the sheet-like connector 8 along the width direction of the guide groove 4 are respectively connected to the two sides of the blade 1 of the guide groove 4 and / or the detonator groove 5.

[0040] After the explosive device 6 is detonated by the detonator 7, the explosive energy acts on the plate-shaped connector 8. Under the inertial reaction of the plate-shaped connector 8, the explosive energy is directed to the thickness direction of the blade 1, producing a cutting effect. The inertial restraint devices on both sides act simultaneously to cut the airfoil section. This structure can reduce the amount of explosives used, has high reliability, and the plate-shaped connector 8 has almost no impact on the airfoil and has little impact on adjacent structures.

[0041] In some embodiments, the sheet-like connector 8 extends along the guide groove 4 and / or the detonator groove 5. In some embodiments, the guide groove 4 and the detonator groove 5 are arranged side by side along the flow channel section 3 and both extend along the flow channel section 3.

[0042] In this embodiment, the surface of blade 1 is arc-shaped. The flow channel section 3 of blade 1 forms an airfoil structure.

[0043] The sheet-like connector 8 is bonded to the blade 1. The surface of the guide groove 4 is covered with a high-density sheet-like connector 8, which is cut according to the actual geometry of the airfoil surface and fixed to the airfoil surface with epoxy resin structural adhesive as an inertial restraint device.

[0044] In some embodiments, the sheet connector 8 is made of metal. Preferably, the sheet connector 8 is a high-density thin metal sheet.

[0045] The edge of the blade 1 is provided with a metal edging 2, and the guide groove 4 and / or detonator groove 5 pass through the metal edging 2.

[0046] Guide grooves 4 and detonator grooves 5 are provided on two opposing surfaces of the blade 1. Explosive devices 6 are provided in the guide grooves 4 on the two surfaces of the blade 1, and detonators 7 are provided in the detonator grooves 4 on the two surfaces of the blade 1. The detonators 7 are connected to the explosive devices 6 located on the same surface of the blade 1.

[0047] Two detonators 7, located on two different surfaces of blade 1, are connected to the same detonation controller and are detonated simultaneously by the detonation controller.

[0048] In some embodiments, the explosive device 6 includes a detonating cord 6.

[0049] This invention involves creating guide grooves 4 and detonator grooves 5 of specific depth and width along the flow channel section 3 on the upper and lower surfaces of an aero-turbine engine blade 1. The guide grooves 4 and detonator grooves 5 extend into and cut off the leading edge metal cladding 2. A detonating cord 6 of a specific length is cut and placed within the guide groove 4 along the flow channel section 3. Simultaneously, a high-precision detonator 7 is fixed within the detonator groove 5 and contacts the explosive device 6. The surface of the guide groove 4 is covered with a sheet-like connector 8, which can be made of high-density metal sheets such as copper, lead, or gold, cut according to the actual geometry of the airfoil surface. Epoxy resin structural adhesive is used to fix the thin metal sheet to the airfoil surface and cover the guide groove 4, serving as an inertial restraint device, thus forming a combined explosive structure of guide grooves and thin metal sheet coverage.

[0050] Two high-precision military detonators 7 are fixedly installed in the two detonator slots 5 on the upper and lower surfaces. Epoxy resin structural adhesive can be used to bond the high-precision military detonators 7 to the detonator slots 5, improving the reliability of the fixation. The two high-precision military detonators 7 are connected by a lead wire. In the containment test, the high-precision military detonators 7 on the upper and lower surfaces are simultaneously activated by a detonator, detonating the explosive device 6 in contact with them. The detonation wave propagates along the explosive device 6 in the guide slot 4 to the other side of the airfoil, eventually spreading throughout the entire flow channel section 3. The expanding gas generated by the explosion acts on the plate-shaped connector 8, and the plate-shaped connector 8 simultaneously generates a reaction force on the expanding gas. Under this inertial reaction force, the explosion energy is directed to the thickness direction of the blade 1, penetrating deep into the flow channel section 3 to produce a cutting effect. The inertial restraint devices on the upper and lower sides act simultaneously, cutting the flow channel section 3 from two directions, ultimately severing the blade 1.

[0051] This invention significantly simplifies the structure of the explosive airfoil device, resulting in a concise and clear overall design. The grooved surface of the three-dimensional arc-shaped cross-section is easy to manufacture, avoiding the high-difficulty machining required by traditional methods of drilling holes along the curve at the center of the cross-section. The explosive energy primarily originates from the explosive device, which typically has a diameter of only about 3mm. The entire device uses minimal explosives, posing a low risk and ensuring high reliability. The thin metal covering has minimal impact on the airfoil and adjacent structures. Furthermore, cutting along the cross-section from both top and bottom directions improves the flatness of the fracture surface. Multiple tests have verified its excellent performance.

[0052] The above are merely exemplary embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A test blade for an aero-engine blade containment test, characterized in that, include: Leaf (1); Guide groove (4) extends along the surface of the blade (1); The detonator groove (5) extends along the surface of the blade (1) and is connected to the guide groove (4); An explosive device (6) is disposed in the guide groove (4); A detonator (7) is disposed in the detonator slot (5) and connected to the explosive device (6); and A sheet-like connector (8) is provided on the guide groove (4) and / or the detonator groove (5), and the two ends of the sheet-like connector (8) along the width direction of the guide groove (4) are respectively connected to the blades (1) on both sides of the guide groove (4) and / or the detonator groove (5). The sheet connector (8) is bonded to the blade (1).

2. The test blade according to claim 1, characterized in that, The sheet connector (8) extends along the guide groove (4) and / or the detonator groove (5).

3. The test blade according to claim 1, characterized in that, The sheet-like connector (8) is made of metal.

4. The test blade according to claim 1, characterized in that, The edge of the blade (1) is provided with a metal edging (2), and the guide groove (4) and / or the detonator groove (5) penetrate the metal edging (2).

5. The test blade according to claim 1, characterized in that, The surface of the blade (1) is arc-shaped.

6. The test blade according to claim 1, characterized in that, The blade (1) has guide grooves (4) and detonator grooves (5) on two opposite surfaces. The guide grooves (4) on the two surfaces of the blade (1) are respectively provided with explosive devices (6), and the detonator grooves (4) on the two surfaces of the blade (1) are respectively provided with detonators (7). The detonators (7) are connected to the explosive devices (6) located on the same surface of the blade (1).

7. The test blade according to claim 6, characterized in that, The two detonators (7) located on two surfaces of the blade (1) are connected to the same detonation controller and are detonated simultaneously by the detonation controller.

8. The test blade according to claim 1, characterized in that, The explosive device (6) includes a detonating cord.

9. The test blade according to claim 1, characterized in that, The guide groove (4) and the detonator groove (5) are arranged side by side along the flow channel section (3) and both extend along the flow channel section (3).

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