Blade separation device for containment testing

Abstract

This invention discloses a blade separation device for containment testing. A guide groove for placing the blade separation device is formed on the cross-section of the blade's flow channel. The blade separation device for containment testing includes a shell, a partition, an explosive body, and a shear-hardening colloid. A receiving cavity is formed inside the shell; the partition divides the receiving cavity into an explosive cavity and an energy confinement cavity; the explosive body is placed in the explosive cavity; the shear-hardening colloid fills the energy confinement cavity, causing the blade to break and separate along the flow channel cross-section to meet the requirements of the containment test. The shear-hardening colloid, in conjunction with the partition, provides explosive energy confinement, replacing the metal materials contained in traditional explosive devices. This avoids the generation of high-temperature, high-speed molten metal debris after the explosion, resulting in low risk. It also has the advantage of being lightweight, reducing the impact on the overall rotor dynamic balance, and is simple and convenient to install.

Description

Technical Field

[0001] This invention relates to the field of aero-turbine engine technology, and in particular to a blade separation device for containment testing. Background Technology

[0002] Shear-thickening materials are strain-rate-dependent smart materials, primarily comprising shear-thickening fluids and shear-hardening colloids. The shear-hardening colloid is a borosilicate polymer. Under normal conditions, it is a soft, viscoelastic polymer; however, upon high-speed impact, its storage modulus and strength increase instantaneously several times, exhibiting extremely hard solid properties. It also possesses variable modulus, high damping performance, ease of preparation, and stable performance. Shear-thickening materials are applied in explosive cutting devices, utilizing their modulus and strength characteristics to confine and guide explosive energy. They can replace metallic materials, reducing weight and the probability of secondary accidents.

[0003] Additive manufacturing (3D printing) is a rapid prototyping technology that uses powdered, bondable materials, such as metal powder and plastic powder, to construct objects by stacking layers one by one, directly creating three-dimensional solids of almost any shape. Additive manufacturing technology is applied to the manufacture of explosive encapsulation shells. Based on its ability to process a variety of flexible internal structures, it can effectively improve the confinement of explosive energy through the design of locally reinforced structures while minimizing the weight of the explosive device.

[0004] 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 systems. 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's ability to contain high-speed ejected blades and withstand corresponding unbalanced loads.

[0005] Enclosure tests on 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 key factor determining the success or failure of the test. Aero-turbine engine blades have a leading-edge metal cladding and a flow channel section. Civil aviation airworthiness regulations explicitly require that during enclosure tests, the blade should break apart along the flow channel section. With the development of aero-turbine engine technology, the aerodynamic design and materials used in blades have become increasingly complex, resulting in separation sections that are no longer traditional straight sections, but rather curved sections with airfoils (such as the flow channel section of fan blades). These significantly different designs and material properties pose new challenges to blade release methods.

[0006] Currently, there are three common release methods. The first method is the pre-defect method, which 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-made 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 of the blade release timing is poor, making it difficult to meet the requirements of complex structures and high-precision tests. The second method is the heated fly-off method, which is based on the principle that the mechanical properties of metallic materials decrease with increasing temperature. A heater is pre-embedded at a specific location on the blade. During the test, after the rotor reaches a predetermined speed, the heater is activated to heat the blade, causing a local temperature increase and a decrease in material properties. After continuous heating for a period of time, the blade separates under centrifugal force. This technology has a narrow scope of application, only suitable for blades made of specific metal materials. Furthermore, because continuous heating is required, the interval between activating the heater and blade separation is relatively long, making it difficult to accurately control the blade separation timing. The third method is the explosive fly-off method. In this method, an explosive (such as a shaped-jet cutter) is placed at a designated location on the blade, and the explosive is ignited at a specified release speed. The energy generated at the moment of the explosion cuts off the blade, causing it to 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 device contains a large amount of metal, and after the explosion, a large amount of high-temperature and high-speed metal debris is generated, which can easily cause secondary accidents; (2) The explosive device has a large structural weight, which affects the balance of the entire test piece rotor and can easily cause vibration and other problems under high-speed rotation. Summary of the Invention

[0007] The technical problem to be solved by the present invention is to overcome the shortcomings of the existing technology in which the traditional explosive fly-off method is difficult and unreliable to install the explosive device on the flow channel section when conducting containment tests, which seriously affects the rotor dynamic balance and blade aerodynamic shape. The metal material contained in the device generates high-temperature and high-speed metal debris after the explosion, which can easily lead to secondary accidents and is highly dangerous. The present invention provides a blade separation device for containment tests.

[0008] The present invention solves the above-mentioned technical problems through the following technical solution:

[0009] A blade separation device for containment testing, wherein a guide groove for placing the blade separation device is formed on the cross-section of the flow channel of the blade, the blade separation device for containment testing comprising:

[0010] A housing having an internal cavity;

[0011] A partition divides the receiving cavity into an explosive cavity and an energy confinement cavity;

[0012] An explosive body, wherein the explosive body is placed inside the explosive cavity;

[0013] A shear-hardening colloid is filled within the energy confinement cavity. Under the explosive impact of the explosive, the shear-hardening colloid rapidly increases its stiffness and strength. The energy generated by the explosive explosion is directed to the thickness direction of the blade by the inertial reaction of the shear-hardening colloid, producing a cutting effect that causes the blade to break and separate along the flow channel cross-section, thus meeting the requirements of the containment test.

[0014] In this scheme, the blade separation device used for containment testing is equipped with shear-hardening colloid and baffles to confine the explosion energy, replacing the metal materials contained in traditional explosion devices. This avoids the generation of high-temperature and high-speed molten metal fragments after the explosion, resulting in low risk. It also has the advantage of being lightweight, reducing the impact on the dynamic balance of the entire rotor, and is simple and convenient to install.

[0015] Preferably, the explosive body is a zero-oxygen balance explosive.

[0016] In this scheme, the explosive body uses zero-oxygen balance explosive. The oxygen content in this explosive is just enough to completely oxidize substances such as carbon, hydrogen, and nitrogen. The heat of the explosive is released most fully, and the explosion products are water, carbon dioxide, nitrogen, etc. There are no unreacted solid particles or smoke that obstruct the view, which is most advantageous for observing the experimental process.

[0017] Preferably, the partition includes a plurality of support rods, which are disposed inside the partition and intersect to form a truss support structure.

[0018] In this design, staggered support rods are installed in the partition to form a truss support structure, which not only reduces the weight of the outer shell but also ensures that the partition maintains sufficient rigidity and strength. This, together with the shear-hardening adhesive in the energy confinement cavity, helps to confine and guide the explosive energy of the explosive.

[0019] Preferably, the interior of the housing is uniformly provided with elastic support structures so that the blade separation device for containment testing can better fit the guide groove.

[0020] In this design, the shell has a hollow structure and evenly distributed elastic support structures, which not only reduces the weight of the shell, but also makes the shell easy to bend locally and maintain its shape, thus better fitting the guide groove.

[0021] Preferably, the housing comprises:

[0022] The first outer wall panel is in contact with the cross-section of the flow channel;

[0023] The second outer wall panel is perpendicularly connected to the first outer wall panel, and the second outer wall panel is fitted to the opening of the guide groove;

[0024] An inclined wall panel, wherein the inclined wall panel connects the two ends of the first outer wall panel and the second outer wall panel that are not connected.

[0025] In this solution, the above-mentioned structural form can ensure the flushness of the separation cut.

[0026] Preferably, the guide groove is disposed on the surface of the flow channel cross-section.

[0027] In this solution, placing the guide groove on the surface of the flow channel section can reduce the processing difficulty and avoid the high-difficulty processing of drilling holes along the curve direction at the center of the section using traditional methods.

[0028] Preferably, the number of guide grooves is two.

[0029] In this design, two guide slots are provided to cut from two directions simultaneously, reducing the impact of the explosion on the circumferential forces on the blades.

[0030] Preferably, the guide groove cuts off the leading edge metal edging of the blade.

[0031] In this design, the aforementioned structural form further ensures that the blades break apart along the flow channel cross-section.

[0032] Preferably, the guide groove is an inverted right triangle.

[0033] In this design, the aforementioned structural form can further reduce the impact of the explosion on the circumferential forces on the blades.

[0034] Preferably, the opening of the guide groove is covered with several layers of carbon fiber cloth.

[0035] In this scheme, the above-mentioned structural form can ensure that the guide groove does not affect the aerodynamic shape of the blade, and can also greatly reduce the impact of the guide groove on adjacent structures.

[0036] The positive and progressive effects of this invention are as follows: The blade separation device for containment testing of this invention uses shear-hardening colloid in conjunction with a partition to confine the explosion energy, replacing the metal materials contained in traditional explosion devices. This avoids the generation of high-temperature and high-speed molten metal fragments after the explosion, thus reducing the risk. At the same time, it also has the advantage of being lightweight, reducing the impact on the dynamic balance of the entire rotor, and is simple and convenient to install. Attached Figure Description

[0037] Figure 1 This is a schematic diagram of the blade structure of a blade separation device for containment testing, which is equipped with a preferred embodiment of the present invention.

[0038] Figure 2 This is a schematic diagram showing the overall distribution of the blade separation device for containment testing according to a preferred embodiment of the present invention on the blade.

[0039] Figure 3 The flow channel cross-section of the blade separation device for containment testing, as described in a preferred embodiment of the present invention, is along... Figure 1 Projection view of section AA in the middle.

[0040] Figure 4 The blade separation device for containment testing according to a preferred embodiment of the present invention is along... Figure 2 A schematic diagram of the overall distribution of the BB section.

[0041] Figure 5 This is a schematic diagram of the blade separation device for containment testing according to a preferred embodiment of the present invention.

[0042] Figure 6 This is a schematic diagram of the internal structure of the shell of the blade separation device for containment testing according to a preferred embodiment of the present invention.

[0043] Figure 7 This is a schematic diagram of the internal structure of the diaphragm of the blade separation device for containment testing according to a preferred embodiment of the present invention.

[0044] Explanation of reference numerals in the attached figures:

[0045] Leaf 1

[0046] Metal edging 2

[0047] Flow channel section 3

[0048] Guide groove 4

[0049] Blade separation device 5 for containment testing

[0050] First outer wall panel 6

[0051] Second outer wall panel 7

[0052] 8 inclined wall panels

[0053] partition 9

[0054] Explosive body 10

[0055] Shear-hardening colloid 11

[0056] Carbon fiber cloth 12

[0057] Elastic support structure 13

[0058] Support rod 14 Detailed Implementation

[0059] The present invention will be further illustrated by way of embodiments below, but the present invention is not limited to the scope of the embodiments.

[0060] like Figures 1-4 As shown, this embodiment provides a blade 1 separation device for containment testing. A guide groove 4 for placing the blade 1 separation device for containment testing is provided on the flow channel section 3 of the blade 1. Figure 3 As shown, the flow channel section 3 is a three-dimensional spatial arc surface with an aerodynamic airfoil. A right-angled triangular guide groove 4 of a specific depth is opened on the upper and lower surfaces of the airfoil arc surface according to the cut section. One right-angled side of the guide groove 4 is attached to the predetermined separation surface. The blade 1 separation device used for the containment test is fixed in the guide groove 4 using epoxy resin structural adhesive. Six layers of carbon fiber cloth 12 are glued to the surface with epoxy resin structural adhesive to cover the guide groove 4. This ensures that the guide groove 4 does not affect the aerodynamic shape of the blade 1 and can also greatly reduce the impact of the guide groove 4 on adjacent structures. Of course, those skilled in the art should understand that the number of carbon fiber cloth layers is not limited to six layers.

[0061] like Figure 5 As shown, the blade 1 separation device for containment testing includes a shell, a partition 9, an explosive body 10, and a shear-hardening colloid 11. A plastic shell is 3D printed according to the geometry of the guide groove 4, and an internal containment cavity is formed within the shell; the partition 9 divides the containment cavity into an explosive cavity and an energy confinement cavity.

[0062] like Figure 5As shown, the explosive body 10 is placed inside the explosive cavity; the shear-hardening colloid 11 is filled inside the energy confinement cavity. Under the explosive impact of the explosive body 10, the shear-hardening colloid 11 will rapidly increase its stiffness and strength. The energy generated by the explosion of the explosive body 10 is directed to the thickness direction of the blade 1 under the inertial reaction of the shear-hardening colloid 11, producing a cutting effect, causing the blade 1 to break and separate along the flow channel section 3, so as to meet the requirements of the containment test.

[0063] In this embodiment, the explosive body 10 is a zero-oxygen balance explosive. The explosion products of the zero-oxygen balance explosive do not affect the observation of the containment experiment process. In this embodiment, the explosive body 10 uses a zero-oxygen balance explosive. The oxygen content in this explosive is just enough to completely oxidize substances such as carbon, hydrogen, and nitrogen. The heat release of the explosive is most complete, and the explosion products are water, carbon dioxide, nitrogen, etc., without unreacted solid particles or smoke obstructing the view, which is most advantageous for observing the experimental process. However, this zero-oxygen balance explosive is highly sensitive and cannot be placed directly into the guide groove 4. Therefore, the blade 1 separation device used for the containment experiment needs to be processed according to the geometry of the guide groove 4, and the explosive needs to be encapsulated in the blade 1 separation device used for the containment experiment through an insulating shell. Finally, it is fixed in the guide groove 4 with epoxy resin structural adhesive.

[0064] In this embodiment, the blade 1 separation device used for containment testing is equipped with shear-hardening colloid 11 in conjunction with partition 9 to confine the explosion energy, replacing the metal materials contained in traditional explosion devices. This avoids the generation of high-temperature and high-speed molten metal fragments after the explosion, resulting in low risk. It also has the advantage of being lightweight, reducing the impact on the dynamic balance of the entire rotor, and is simple and convenient to install.

[0065] like Figure 7 As shown, the partition 9 includes several support rods 14, which are arranged inside the partition 9 and intersect to form a truss support structure.

[0066] In this embodiment, the partition 9 is provided with staggered support rods 14 to form a truss support structure, which not only reduces the weight of the outer shell, but also enables the partition 9 to maintain sufficient rigidity and strength, thereby working together with the shear hardening adhesive in the energy confinement cavity to confine and guide the explosive energy of the explosive body 10.

[0067] like Figure 6 As shown, the interior of the shell is uniformly distributed with elastic support structures 13 so that the blade 1 separation device used for containment testing can better fit the guide groove 4.

[0068] In this embodiment, the shell has a hollow structure inside and elastic support structures 13 are evenly distributed, which not only reduces the weight of the shell, but also makes the shell easy to bend locally and maintain its shape, thereby better fitting the guide groove 4.

[0069] like Figure 4 and Figure 5 As shown, the shell includes a first outer wall plate 6, a second outer wall plate 7, and an inclined wall plate 8. The first outer wall plate 6 is in contact with the flow channel section 3; the second outer wall plate 7 is perpendicularly connected to the first outer wall plate 6 and is in contact with the opening of the guide groove 4; the inclined wall plate 8 connects the two ends of the first outer wall plate 6 and the second outer wall plate 7 that are not connected.

[0070] In this embodiment, the above-described structural form ensures that the separation cut surfaces are flush.

[0071] like Figure 1 , Figure 2 and Figure 4 As shown, the guide groove 4 is provided on the surface of the flow channel section 3.

[0072] In this embodiment, placing the guide groove 4 on the surface of the flow channel section 3 can reduce the processing difficulty and avoid the high-difficulty processing of drilling holes along the curve direction at the center of the section using traditional methods.

[0073] like Figure 3 and Figure 4 As shown, there are two guide grooves 4.

[0074] In this embodiment, two guide grooves 4 are provided to cut from two directions simultaneously, reducing the impact of the explosion on the circumferential force of the blade 1.

[0075] like Figure 1 and Figure 2 As shown, the guide groove 4 cuts off the leading edge metal edging 2 of the blade 1.

[0076] In this embodiment, the above-described structure can further ensure that the blade 1 breaks apart along the flow channel section 3.

[0077] While specific embodiments of the present invention have been described above, those skilled in the art should understand that these are merely illustrative examples, and the scope of protection of the present invention is defined by the appended claims. Those skilled in the art can make various changes or modifications to these embodiments without departing from the principles and essence of the present invention, but all such changes and modifications fall within the scope of protection of the present invention.

Claims

1. A blade separation device for containment testing, wherein a guide groove for placing the blade separation device for containment testing is formed on the cross-section of the blade's flow channel, characterized in that, The blade separation device for the containment test includes: A housing having an internal cavity; A partition divides the receiving cavity into an explosive cavity and an energy confinement cavity; An explosive body, wherein the explosive body is placed inside the explosive cavity; Shear-hardening colloid, which is filled in the energy confinement cavity, rapidly increases stiffness and strength under the explosive impact of the explosive body. The energy generated by the explosion of the explosive body is directed to the thickness direction of the blade under the inertial reaction of the shear-hardening colloid, producing a cutting effect, causing the blade to break and separate along the flow channel section to meet the requirements of the containment test. in, The partition includes a plurality of support rods, which are disposed inside the partition and are staggered to form a truss support structure. The guide groove is provided on the surface of the flow channel section, the guide groove cuts off the leading edge metal edging of the blade, and the guide groove is an inverted right triangle.

2. The blade separation device for containment testing as described in claim 1, characterized in that, The explosive body is a zero-oxygen balance explosive.

3. The blade separation device for containment testing as described in claim 1, characterized in that, The interior of the housing is uniformly distributed with elastic support structures to allow the blade separation device used for containment testing to better fit the guide groove.

4. The blade separation device for containment testing as described in claim 3, characterized in that, The housing includes: The first outer wall panel is in contact with the cross-section of the flow channel; The second outer wall panel is perpendicularly connected to the first outer wall panel, and the second outer wall panel is fitted to the opening of the guide groove; An inclined wall panel, wherein the inclined wall panel connects the two ends of the first outer wall panel and the second outer wall panel that are not connected.

5. The blade separation device for containment testing as described in claim 1, characterized in that, The number of guide grooves is two.

6. The blade separation device for containment testing as described in claim 1, characterized in that, The opening of the guide groove is covered with several layers of carbon fiber cloth.

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