Laser processing method for fan-shaped air film hole of aero-engine

Abstract

The invention discloses a laser machining method for a fan-shaped air film hole of an aero-engine, the fan-shaped air film hole comprises a cylinder-like section, an original fan-shaped section and an expanded fan-shaped section, and the laser machining method comprises the following steps that S1, all coatings in an area are removed through multiple rows of laser beams, the area comprises the original fan-shaped section and the expanded fan-shaped section; s2, a low-power laser beam is used for multiple times of irradiation to remove the area of the coating so as to penetrate through the metal material; s3, irradiating by using a single-row multi-beam laser beam to form the original fan-shaped section; s4, irradiating by using a plurality of rows of laser beams to form the expanded fan-shaped section; and S5, laser is used for cutting the round hole to form the similar cylindrical section.

Description

Technical Field

[0001] This application relates to the technical fields of gas engines and aero-engines, specifically to the manufacturing fields of gas engines and aero-engines, and more specifically, to a laser processing method for fan-shaped film holes used in aero-engines. Background Art

[0002] As is well known, as the power source of modern aircraft, aero-engines are mainly divided into turbofan engines and turbojet engines. Their structures are advanced and complex, and they are typical high-tech intensive products, known as the "crown of industry". Developing aero-engines with high thermal efficiency and high thrust-to-weight ratio is an important symbol of a country's high-tech level and scientific and technological strength.

[0003] In order to continuously improve the performance, enhance the combustion efficiency, and ensure the thrust-to-weight ratio of modern aero-engines, the temperature of the hot-end components has risen. To ensure the long-term effectiveness of the thermal protection of the hot-end components in a high-temperature environment, film cooling technology is often used to cool the hot-end components.

[0004] The basic principle of film cooling is as follows: Secondary air flow is introduced from the holes on the wall surface of the high-temperature environment. This cold air flow bends downstream under the action of the pressure and frictional force of the mainstream, adheres to a certain area of the wall surface, forms a cold air film with a lower temperature to isolate the wall surface from the high-temperature combustion gas, and takes away part of the radiant heat of the high-temperature combustion gas on the part wall surface, thus playing a good role in cooling and protecting the wall surface. However, film cooling requires extracting low-temperature air from the compressor as the cooling working medium. The extensive use of cooling air will inevitably lead to the decline of the overall performance of the engine.

[0005] Therefore, the key to strengthening film cooling lies in: on the premise of meeting the thermal protection of the hot-end components, reducing the usage amount of cold air as much as possible. In the past few decades, relevant researchers have made great efforts both from a scientific perspective and a technical perspective.

[0006] The fan-shaped hole is a common film hole in the hot-end components of aero-engines. It is shaped like a broom and consists of a quasi-cylindrical section and a fan-shaped section. The air flow enters from the quasi-cylindrical section and flows out from the fan-shaped section to form a fan-shaped air film, which plays a role in cooling and protecting the wall surface of the hot-end components. Compared with ordinary quasi-cylindrical film holes, the fan-shaped hole can suppress the adverse effects brought by the kidney-shaped vortex and improve the spanwise coverage rate of the air film. Therefore, the film holes in the hot-end components of advanced aero-engines mostly adopt fan-shaped film holes to ensure the film cooling effect. Moreover, the wall surface of the flame tube in the hot-end components of aero-engines is generally coated with a thermal barrier coating, and the thermal barrier coating is not conductive, so electrical discharge machining cannot be used. Laser processing has almost become the optimal method for processing film holes.

[0007] The common principle of laser processing of film cooling holes is that a laser beam is incident on the metal surface, the metal absorbs the laser, and the energy diffuses into the material interior. Subsequently, the metal surface begins to melt, metal vapor is generated on the surface, and when the metal vapor is heated to a certain temperature, high-temperature and high-pressure plasma is generated. The instantaneously generated high pressure causes the gas to expand rapidly, forming a violent explosive shock airflow. Finally, the plasma splashes out of the material surface, forming a pit, and finally forming a small hole.

[0008] However, the ordinary fan-shaped hole is limited by the size of the fan-shaped section at its outlet, the air flow cannot further diffuse laterally, the film cannot develop more uniformly in the span direction, and the mutual influence between the mainstream and the jet is inevitable, making it difficult to further enhance the cooling effect of the film. For the above reasons, a new processing method for fan-shaped expansion holes is needed to effectively increase the spanwise size at the outlet of the film cooling hole. Moreover, while effectively improving the cooling efficiency of the film cooling hole, this hole type should also meet various requirements such as simple processing technology, short time, and high efficiency.

[0009] Therefore, there is an urgent need in the art for an improved laser processing method for fan-shaped holes used in aeroengines. Summary of the Invention

[0010] A brief overview of one or more aspects is given below to provide a basic understanding of these aspects. This overview is not an exhaustive survey of all contemplated aspects, and is neither intended to identify key or decisive elements of all aspects nor to define the scope of any or all aspects. Its sole purpose is to present some concepts of one or more aspects in a simplified form as a prelude to the more detailed description that follows.

[0011] The ordinary fan-shaped hole processing method is difficult to increase the area of the fan-shaped section, resulting in the film being difficult to develop more uniformly in the span direction, and the mutual influence between the mainstream and the jet is inevitable, thus affecting the cooling effect of the hole. This application proposes a new processing method for fan-shaped film cooling holes (hereinafter referred to as "fan-shaped expansion holes"). The formed fan-shaped expansion hole increases the area of the fan-shaped section compared to the ordinary fan-shaped film cooling hole, improves the coverage area of the film, and thus significantly enhances the cooling effect of the film.

[0012] According to a first aspect of the present application, a laser processing method for fan-shaped film cooling holes used in an aeroengine is disclosed, wherein the fan-shaped film cooling hole includes a cylindrical-like section, an original fan-shaped section, and an expanded fan-shaped section, and the laser processing method includes the following steps:

[0013] S1 - Coating removal stage: Use multiple rows of low-power laser beams to remove all coatings in the area, which includes the original fan-shaped section and the expanded fan-shaped section;

[0014] S2 - Piercing stage: Use multiple low - power laser beams to irradiate along the axis of this type of cylindrical segment multiple times to penetrate the metal material;

[0015] S3 - Forming the original sector segment: Use a single row of multiple laser beams to irradiate to form the original sector segment; and

[0016] S4 - Forming the expanded sector segment: Use multiple rows of low - power laser beams to irradiate to form the expanded sector segment; and

[0017] S5 - Forming this type of cylindrical segment: Use a single row of multiple laser beams to cut along an elliptical cutting path to form this type of cylindrical segment.

[0018] According to a preferred embodiment of the present application, using multiple rows of low - power laser beams to remove all coatings in the area includes: using 2 - 4 rows of laser beams to remove all coatings in the area, and each row of laser beams includes 7 - 15 laser pulses, and the power of each laser pulse is between 800 - 2000w.

[0019] According to a preferred embodiment of the present application, using multiple low - power laser beams to irradiate multiple times to penetrate the metal material includes:

[0020] Use 5 - 15 laser beams to perform the piercing operation, and the power of the laser pulses of the first 2 - 5 beams is between 2000 - 5500w, while the power of the laser pulses in the remaining laser beams is between 6000 - 10000w.

[0021] According to a preferred embodiment of the present application, using a single row of multiple laser beams to irradiate to form the original sector segment includes:

[0022] The power of each laser pulse in the multiple laser beams gradually decreases from the center of the original sector segment to both sides, and the decreasing amplitude depends on the size of the divergence angle of the original sector segment.

[0023] According to a preferred embodiment of the present application, the laser power for irradiating the expanded sector segment is less than the laser power for irradiating the original sector segment to prevent cracking of the coating.

[0024] According to a preferred embodiment of the present application, using multiple rows of low - power laser beams to irradiate to form the expanded sector segment includes:

[0025] Use 2 - 5 rows of laser beams to irradiate to form the expanded sector segment, where each row of laser beams includes 8 - 20 laser pulses, and for the expanded sector segment, the power of each laser pulse gradually decreases from left to right, and each row of laser beams gradually decreases from the middle to both sides.

[0026] According to a preferred embodiment of the present application, three rows of laser beams are used to irradiate to form the expanded fan-shaped segment, wherein the power of the first row of laser beams is 5000 - 2000w, the power of the second row of laser beams is 4000 - 1500w, and the power of the third row of laser beams is 3000 - 1000w.

[0027] According to a preferred embodiment of the present application, the path of using the laser beam to cut the circular hole is an elliptical cutting path so that the processing result is circular.

[0028] According to a preferred embodiment of the present application, the ratio of the major axis to the minor axis of the ellipse is between 1.1 - 1.4.

[0029] According to a second aspect of the present application, a computer-readable storage medium storing a computer program is disclosed, the computer program includes computer-executable instructions, and when the computer-executable instructions are executed by a computer, each step of the laser processing method of the fan-shaped air film hole as described above is executed.

[0030] To achieve the foregoing and related purposes, one or more of these aspects include the features described in detail below and particularly pointed out in the appended claims. The following description and the drawings elaborate certain illustrative features of one or more of these aspects. However, these features are merely indicative of several of the various ways in which the principles of the various aspects may be employed, and this description is intended to cover all such aspects and their equivalents. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] For a more particular description of the manner in which the above-recited features of the present application can be understood, reference may be made to the aspects, some of which are illustrated in the drawings. It should be noted, however, that the drawings illustrate only certain typical aspects of the present application and should not be considered as limiting its scope, as the description may admit of other equally effective aspects.

[0032] In the drawings:

[0033] Figure 1 is a side view of a fan-shaped expansion hole illustrating an embodiment according to the present application;

[0034] Figure 2 is a top view of a fan-shaped expansion hole illustrating an embodiment according to the present application;

[0035] Figure 3 is a detailed flowchart of a processing method of a fan-shaped expansion hole illustrating an embodiment according to the present application;

[0036] Figure 4 is a schematic diagram of an elliptical cutting path trajectory of a fan-shaped expansion hole illustrating an embodiment according to the present application; and

[0037] Figure 5 The overall schematic diagram of the machined and formed fan-shaped expansion hole according to an embodiment of the present application is shown. Detailed implementation manners

[0038] The following detailed description set forth in conjunction with the accompanying drawings is intended as a description of various configurations and is not intended to represent the only configurations in which the concepts described herein may be practiced. The detailed description includes specific details for providing a thorough understanding of the various concepts. However, it will be apparent to those skilled in the art that these concepts may be practiced without these specific details. In some instances, well-known components are shown in block diagram form to avoid obscuring such concepts.

[0039] It should be understood that other embodiments will be apparent based on the present disclosure and that system, structural, process, or mechanical changes may be made without departing from the scope of the present disclosure.

[0040] Refer to Figures 1 to 3 , aspects are depicted with reference to one or more components and one or more methods that can perform the actions or functions described herein. In one aspect, the term "component" as used herein can be one of the parts that make up a system, can be hardware or software or some combination thereof, and can be divided into other components. Although the operations described below in Figure 3 are presented in a particular order and / or as performed by example components, it should be understood that the order of these actions and the components performing the actions can vary depending on the implementation. Additionally, it should be understood that the following actions or functions can be performed by a specially programmed processor, a processor executing specially programmed software or a computer-readable medium, or any other combination of hardware components and / or software components capable of performing the described actions or functions.

[0041] As Figure 1 shown in

[0042] , a side view of the fan-shaped expansion hole as described in the present application is shown.

[0043] It can be seen that the fan-shaped expansion hole includes a quasi-cylindrical section 10, an original fan-shaped section 20, and an expanded fan-shaped section 30. The arrow marks show the laser incident directions for different sections.

[0044] Figure 2 The top view of the fan-shaped expansion hole as described in the present application is shown in

[0045] And Figure 1Similarly, it can also be seen that the fan-shaped expansion hole includes a quasi-cylindrical section 10, an original fan-shaped section 20, and an expanded fan-shaped section 30. The arrow marks show the laser incident directions for different sections.

[0046] Similarly, the incident direction of the laser beam for machining the quasi-cylindrical section 10 is marked 1, the incident direction of the laser beam for machining the original fan-shaped section 20 is marked 2-7, and the incident direction of the laser beam for machining the expanded fan-shaped section 30 is marked 8-12.

[0047] The following combines the attached Figure 1 and 2 and combines Figure 3 to describe in detail the specific process of the machining method of the fan-shaped expansion hole according to the present application.

[0048] As Figure 3 shown, the laser machining method of the fan-shaped expansion hole mainly includes the following steps.

[0049] Step S1: Coating removal stage

[0050] In the coating removal stage, the coating on the surface of the part is removed by moving the laser spot and using multiple single-pulse lasers. The purpose is to reduce the delamination gap of the coating to improve the service life of the coating. Its incident direction refers to (1-12), that is, the coating is swept away in the area to be machined soon.

[0051] In the present application, all the coatings in the fan-shaped section area of the fan-shaped expansion hole need to be removed in the coating removal stage, and its area is larger than that of the fan-shaped section area of the ordinary fan-shaped hole. In the traditional process, the coating in the fan-shaped section area is removed by using a row of laser beams with a common power, while according to the machining method of the present application, multiple rows of low-power laser beams need to be used for machining, and each row of laser beams contains several laterally moving lasers.

[0052] Specifically, as a non-limiting example, the multiple rows of low-power laser beams can be, for example, 2-4 rows, with 7-15 laser pulses in each row. The power of the conventional laser beam is about 2000-3500w, while the power of the low-power laser beam adopted in the present application is between 800-2000w. In this way, on the one hand, it not only ensures the increase of the machining area, but also avoids the coating cracking caused by using high-power lasers.

[0053] Step S2: Drilling stage

[0054] In the drilling stage, multiple single-pulse lasers are used to penetrate the metal layer, so that the metal spatter generated by the subsequent profiling can pass through the hole, thereby eliminating the increase of the coating delamination gap caused by the spatter recoil during profiling and reducing the heat accumulation during profiling. Its incident direction continues to refer to (1), and this direction is incident along the center of the quasi-cylindrical section.

[0055] Since more metal material needs to be cut for the fan-shaped expansion holes, the accumulation problem of thermal effects needs to be considered emphatically. If high-power lasers are used in the perforation stage, it is very easy to cause the melting and accumulation of metals. Therefore, according to the processing method of the present application, the laser power should be reduced in the perforation stage, and the metal material should be penetrated multiple times with lasers of relatively low power.

[0056] Under normal circumstances, multiple laser beams are used for the perforation operation, such as 5 - 15 beams, and the laser power is about 6000 - 10000w. However, considering to avoid the occurrence of heat accumulation, the present application reduces the laser beam power of the first 2 - 5 beams appropriately for the perforation operation. In this way, the laser power of the first 2 - 5 beams is about 2000 - 5500w. Therefore, multiple incidences with lasers of relatively low power can effectively avoid the problem of heat accumulation.

[0057] As can be understood by those skilled in the art, the power value and the number of laser beams are only preferred values, which do not limit the scope of the present application. Those skilled in the art can select different power ranges according to the part size and the limitations of the processing technology, and these ranges and values all fall within the scope of the present application.

[0058] Step S3: Scanning of the original fan-shaped segment

[0059] By laterally moving the laser spot, with its incident direction referring to (2 - 7), the original fan-shaped segment is processed with multiple single-pulse lasers. The energy of each single pulse gradually decreases from the center to both sides of the fan-shaped hole, and the decreasing amplitude of the energy determines the divergence angle. By using multiple lasers, the original fan-shaped segment can be scanned out.

[0060] This step is basically similar to the prior art. It should be noted that the power of the laser pulses gradually decreases from the middle to both sides, so as to further avoid the accumulation of heat.

[0061] Step S4: Scanning of the expanded fan-shaped segment

[0062] After the scanning of the original fan-shaped segment is completed, the expanded fan-shaped segment area is processed separately. Since the expanded fan-shaped segment is closer to the outside, the metal cutting amount is less. Therefore, the laser power needs to be reduced to prevent the occurrence of coating cracking.

[0063] According to the processing method of the present application, by laterally moving the laser spot, the incident reference direction is (8 - 12). This is processed in several rows, and each row uses multiple single-pulse lasers to process the expanded segment. The energy of the beam gradually decreases from the center to both sides of the expanded segment, and the expanded fan-shaped segment is scanned out by using multiple single-pulse lasers.

[0064] Specifically, as a non-limiting example, the solution of the present application may employ 2-5 rows of laser beams, with 8-20 laser beams in each row. And as described above, the power of each laser pulse gradually decreases from left to right, and the power of each row of laser beams gradually decreases from the middle to both sides. For example, the power of the first row of laser beams may be 5000-2000w; the power of the second row of laser beams may be 4000-1500w; and the power of the third row of laser beams may be 3000-1000w, and so on.

[0065] S5: Machining stage of the cylindrical-like section

[0066] In this stage, the sector hole straight section (cylindrical-like section) is machined mainly by using a laser to cut circular holes, and the incident direction is referred to (1).

[0067] However, in the actual machining process, since the cutting parameters are often set as circular during the machining of circular holes, but the machining result is elliptical, therefore, during the machining of the part, the circular hole part is corrected, and the circular cutting path is changed to an elliptical cutting path. In this way, during the actual operation, the actual machining effect can be ensured to be basically circular ( Figure 4 marked as L2 in

[0068] Figure 4 The elliptical cutting path as described above is shown in Figure 4 marked as L1 in

[0069] As Figure 4 shown in

[0070] Specifically, as a non-limiting example, the ratio of the major axis to the minor axis of the ellipse may be between 1.1-1.4, such as 1:0.8. However, as those skilled in the art can understand, this value can be actually set by them according to actual process requirements, the size of the sector hole, and other factors. These ranges and values all fall within the scope of the present application.

[0071] By using the laser machining method as described above, on the basis of machining the ordinary sector hole, the laser is used again for profiling, and the sector area of the expansion section can be machined. The overall structure of the machined sector expansion hole is as Figure 5 shown in

[0072] By adopting the laser processing method with fan-shaped expansion holes of the present application, the structure of the expansion section of the processed fan-shaped expansion holes can effectively weaken the kidney-shaped vortex phenomenon near the outlet of ordinary film holes. The development of the outlet air flow in the spanwise direction is more uniform, thereby avoiding excessive blowing away of the cooling medium from the wall surface, weakening the mutual interference between the mainstream and the jet, effectively improving the cooling efficiency of the film, improving the working environment of the hot-end components of the aero-engine, and enhancing the performance of the aero-engine.

[0073] Moreover, according to the laser processing method of the present application, there is no need to change the incident angle of the laser during processing, which has many advantages such as simple processing technology, short processing time, and high processing efficiency.

[0074] Aspects, elements, or any part of an element, or any combination of elements, according to the present disclosure can be implemented using a "processing system" that includes one or more processors. Examples of processors include: microprocessors, microcontrollers, digital signal processors (DSPs), field programmable gate arrays (FPGAs), programmable logic devices (PLDs), state machines, gated logic, discrete hardware circuits, and other suitable hardware configured to perform the various functions described throughout the present disclosure. One or more processors in the processing system can execute software. Software should be broadly interpreted to mean instructions, instruction sets, code, code segments, program code, programs, subprograms, software modules, applications, software applications, software packages, routines, subroutines, objects, executables, threads of execution, procedures, functions, etc., regardless of whether it is referred to in terms of software, firmware, middleware, microcode, hardware description language, or other terms. The software can reside on a computer-readable medium. The computer-readable medium can be a non-transitory computer-readable medium. As an example, non-transitory computer-readable media include: magnetic storage devices (e.g., hard disks, floppy disks, magnetic strips), optical disks (e.g., compact disks (CDs), digital versatile disks (DVDs)), smart cards, flash memory devices (e.g., memory cards, memory sticks, key drives), random access memory (RAM), read only memory (ROM), programmable ROM (PROM), erasable PROM (EPROM), electrically erasable PROM (EEPROM), registers, removable disks, and any other suitable medium for storing software and / or instructions that can be accessed and read by a computer. As an example, computer-readable media can also include carrier waves, transmission lines, and any other suitable medium for transmitting software and / or instructions that can be accessed and read by a computer. The computer-readable medium can reside within the processing system, outside the processing system, or be distributed across multiple entities including the processing system. The computer-readable medium can be implemented in a computer program product. As an example, the computer program product can include the computer-readable medium in a packaging material. Those skilled in the art will recognize how to best implement the described functionality presented throughout the present disclosure depending on the particular application and overall design constraints imposed on the overall system.

[0075] It should be understood that the specific order or hierarchy of the steps in the disclosed methods is an illustration of an exemplary process. Based on design preferences, it should be understood that the specific order or hierarchy of the steps in the methods or methodologies described herein can be rearranged. The appended method claims present the elements of the various steps in a sample order and are not meant to be limited to the specific order or hierarchy presented, unless specifically recited herein.

[0076] The foregoing description is provided to enable any person skilled in the art to practice the various aspects described herein. Various modifications to these aspects will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other aspects. Thus, the claims are not intended to be limited to the aspects shown herein, but are to be accorded the full scope consistent with the language of the claims, wherein the recitation of a singular element is not intended to mean "one and only one" (unless specifically so stated) but "one or more." Unless specifically stated otherwise, the term "some" refers to one or more. A phrase reciting "at least one" of a list of items refers to any combination of those items, including a single member. As an example, "at least one of a, b, or c" is intended to cover: at least one a; at least one b; at least one c; at least one a and at least one b; at least one a and at least one c; at least one b and at least one c; and at least one a, at least one b, and at least one c. Elements of the various aspects described throughout this disclosure that are presently known or later come to be known to those of ordinary skill in the art as all structural and functional equivalents thereof are expressly incorporated herein by reference and are intended to be covered by the claims. In addition, nothing disclosed herein is intended to be dedicated to the public, whether or not such disclosure is explicitly recited in the claims.

Claims

1. A laser processing method for fan-shaped film cooling holes of an aero-engine, wherein the fan-shaped film cooling holes include a quasi-cylindrical section, an original fan-shaped section, and an expanded fan-shaped section, and the laser processing method comprises the following steps: S1-Coating removal stage: Use multiple rows of low-power laser beams to remove all coatings in the area, which includes the original fan-shaped section and the expanded fan-shaped section; S2-Piercing stage: Use multiple low-power laser beams to irradiate along the axis of the quasi-cylindrical section multiple times to penetrate the metal material; S3-Forming the original fan-shaped section: Use a single row of multiple laser beams to irradiate to form the original fan-shaped section; and S4-Forming the expanded fan-shaped section: Use multiple rows of low-power laser beams to irradiate to form the expanded fan-shaped section; and S5-Forming the quasi-cylindrical section: Use a single row of multiple laser beams to cut along an elliptical cutting path to form the quasi-cylindrical section.

2. The laser processing method for fan-shaped film cooling holes according to claim 1, wherein, using multiple rows of low-power laser beams to remove all coatings in the area includes: Use 2-4 rows of laser beams to remove all coatings in the area, and each row of laser beams includes 7-15 laser pulses, and the power of each laser pulse is between 800-2000w.

3. The laser processing method for fan-shaped film cooling holes according to claim 1, wherein, using multiple low-power laser beams to irradiate multiple times to penetrate the metal material includes: Use 5-15 laser beams to perform the piercing operation, and the power of the laser pulses in the first 2-5 beams is between 2000-5500w, while the power of the laser pulses in the remaining laser beams is between 6000-10000w.

4. The laser processing method for fan-shaped film cooling holes according to claim 1, wherein, using a single row of multiple laser beams to irradiate to form the original fan-shaped section includes: The power of each laser pulse in the multiple laser beams gradually decreases from the center of the original fan-shaped section to both sides, and the decreasing amplitude depends on the size of the divergence angle of the original fan-shaped section.

5. The laser processing method for fan-shaped film cooling holes according to claim 1, wherein, The laser power for irradiating the expanded fan-shaped section is less than the laser power for irradiating the original fan-shaped section to prevent cracking of the coating.

6. The laser processing method for fan-shaped film cooling holes according to claim 1, wherein, using multiple rows of low-power laser beams to irradiate to form the expanded fan-shaped section includes: Use 2-5 rows of laser beams to irradiate to form the expanded fan-shaped section, where each row of laser beams includes 8-20 laser pulses, and for the expanded fan-shaped section, the power of each laser pulse gradually decreases from left to right, and each row of laser beams gradually decreases from the middle to both sides.

7. The laser processing method for fan-shaped film cooling holes according to claim 1, wherein, Use 3 rows of laser beams to irradiate to form the expanded fan-shaped section, where the power of the first row of laser beams is 5000-2000w, the power of the second row of laser beams is 4000-1500w, and the power of the third row of laser beams is 3000-1000w.

8. The laser processing method of the fan-shaped air film hole according to claim 1, characterized in that, the path of using the laser beam to cut the round hole is an elliptical cutting path so that the processing result is a circle.

9. The laser processing method of the fan-shaped air film hole according to claim 1, characterized in that, the ratio of the major axis to the minor axis of the ellipse is between 1.1 and 1.

4.

10. A computer-readable storage medium storing a computer program, the computer program including computer-executable instructions, when the computer-executable instructions are executed by a computer, performing the steps of the laser processing method of the fan-shaped air film hole according to any one of claims 1 to 9.

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