Turbine rotor blade and arrangement method of turbine rotor blade air film holes

Abstract

The present invention relates to a turbine blade and a method for arranging film holes of a turbine blade. An airflow channel is provided inside the turbine blade, a groove is provided on the blade top, the airflow channel and the groove are connected through a plurality of film holes, the blade has a first separation line, and a plurality of film holes are sequentially arranged on the first separation line of the blade. The method for arranging film holes of a turbine blade includes a single-row hole layout method and a full-coverage layout method, both of which include the steps of determining the first separation line of the blade, and sequentially arranging a plurality of film holes on the first separation line, wherein the first separation line is the position of the separation line on the blade under the design working condition. Arranging the film holes on the first separation line generated by the separation vortex can enable the cold air ejected from the film holes to spread on the top of the blade under the influence of the separation vortex, that is, to increase the contact area between the cold air and the blade top, enhance the effectiveness of the air film, and thus obtain a better cooling effect.

Description

Technical Field

[0001] The present invention relates to the technical field of turbine blade film cooling, in particular to a turbine blade and an arrangement method of turbine blade film holes. Background Art

[0002] With the continuous advancement of aircraft engine and gas turbine technology, turbine inlet gas temperatures are also increasing. Currently, inlet gas temperatures far exceed the inherent temperature tolerance of the rotor blade material. To protect the rotor blades from erosion by the high-temperature gas, film cooling is a key technology for advanced aircraft engines and gas turbines. Film cooling is typically implemented in high-temperature, high-heat-load areas such as the blade tips, leading edges, and end zones. On the one hand, the cooling gas does not participate in the combustion and power generation processes, inevitably resulting in reduced power output and efficiency of aircraft engines and gas turbines. On the other hand, the cooling gas is strongly mixed with the mainstream gas, inevitably causing significant aerodynamic losses. Therefore, designing cooling structures suitable for high-heat-load areas, requiring minimal cooling gas, and achieving high cooling efficiency is crucial for the development of advanced aircraft engines and gas turbines.

[0003] The turbine blade tips are typically high-heat-load areas and difficult to cool, requiring film cooling to protect them. Multiple film holes are typically placed in this area, and a reasonable arrangement maximizes cooling and effectively protects the blade tips.

[0004] Regarding the arrangement of air film holes on the top of the moving blade, the common method used in the industry is to set an exhaust film hole along the center arc line of the moving blade. However, the cooling effect of the above method (i.e., the effectiveness of the air film) is limited, which can easily cause local high temperature on the top of the moving blade. Summary of the Invention

[0005] Based on this, it is necessary to provide a method for arranging turbine blades and turbine blade air film holes to address the problem that setting air film holes on the arc line of the blades leads to local high temperature on the blade tips.

[0006] A method for arranging film holes of turbine blades includes a single-row hole layout method and a full-coverage layout method, wherein both the single-row hole layout method and the full-coverage layout method include the following steps:

[0007] Determining a position of a first separation line, where the first separation line is a position of a separation line on the rotor blade under a design operating condition;

[0008] A plurality of air film holes are sequentially arranged on the first separation line.

[0009] In one embodiment, the moving blade is a moving blade having a groove on the blade tip, and the first separation line is a separation line generated by the groove vortex near the pressure side when there is no cold air jet.

[0010] In one embodiment, the full coverage layout method further comprises the steps of:

[0011] Determining the positions of a second separation line and / or a third separation line, wherein the second separation line and the third separation line are respectively two boundary lines of the separation line of the moving blade under variable operating conditions;

[0012] A plurality of air film holes are sequentially arranged on the second separation line and / or the third separation line.

[0013] In one embodiment, the second separation line is the separation line position at the maximum positive attack angle, and the third separation line is the separation line position at the maximum blowing ratio.

[0014] In one embodiment, the separation line position at the maximum positive attack angle refers to the separation line position at the maximum positive attack angle when there is no cold air jet, and the separation line position at the maximum blowing ratio refers to the separation line position at the maximum blowing ratio under the air film holes arranged on the mid-arc line.

[0015] In one embodiment, the single-row hole layout method is applicable to moving blades operating only under design conditions, and the full-coverage layout method is applicable to moving blades operating under variable conditions.

[0016] A turbine blade, wherein an air flow channel is provided inside the blade, a groove is provided on the blade top, the air flow channel is connected to the groove through multiple air film holes, the blade has a first separation line, and multiple air film holes are sequentially provided on the first separation line, wherein the first separation line is the separation line position on the blade under the design working conditions.

[0017] In one embodiment, the moving blade also has a second separation line and a third separation line, and a plurality of the air film holes are sequentially opened on the second separation line and / or the third separation line. The second separation line and the third separation line are respectively two boundary lines of the separation line of the moving blade under variable working conditions.

[0018] In one embodiment, the hole distance between any two adjacent air film holes on the first separation line is equal, and the hole distance between any two adjacent air film holes on the second separation line and / or the third separation line is equal.

[0019] In one embodiment, the distance between two adjacent air film holes is 4-6 times the hole diameter.

[0020] The above-mentioned arrangement method of the turbine blades and the air film holes of the turbine blades sets the air film holes on the separation line (i.e., the first separation line) generated by the separation vortex under the design working conditions, so that the cold air ejected from the air film holes can spread on the top of the blade under the influence of the separation vortex, that is, increase the contact area between the cold air and the top of the blade, enhance the effectiveness of the air film, and thus obtain a better cooling effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 The flowchart of the arrangement method of the film holes of the turbine rotor blades is as follows;

[0022] Figure 2 Schematic diagram of the groove vortex near the pressure side and the first separation line in the blade tip groove;

[0023] Figure 3 Schematic diagram of cold air distribution with air film holes opened on the first separation line;

[0024] Figure 4 This is a schematic diagram of the full coverage layout;

[0025] Figure 5(a) shows the position distribution of the separation line under different blowing ratios when the gap height is 1 mm and the groove depth is 2 mm;

[0026] Figure 5(b) shows the position distribution of the separation line under different blowing ratios when the gap height is 2 mm and the groove depth is 2 mm;

[0027] Figure 5(c) shows the position distribution of the separation line under different blowing ratios when the gap height is 3 mm and the groove depth is 2 mm;

[0028] Figure 6(a) shows the position distribution of the separation line at different attack angles when the gap height is 1 mm;

[0029] Figure 6(b) shows the position distribution of the separation line at different attack angles when the gap height is 2 mm;

[0030] Figure 6(c) shows the position distribution of the separation line at different attack angles when the gap height is 3 mm;

[0031] Figure 6(d) shows the position distribution of the separation line at different gap heights and different positive attack angles;

[0032] Figure 6(e) shows the position distribution of the separation line at different gap heights and different negative attack angles;

[0033] Figure 7(a) is a distribution diagram of five air film holes arranged along the first separation line;

[0034] Figure 7(b) is a schematic diagram showing the effectiveness of the air film hole when the hole 2 produces different displacements;

[0035] Figure 7(c) is a schematic diagram showing the effectiveness of the air film hole when the hole 3 produces different displacements;

[0036] Figure 7(d) is a schematic diagram showing the effectiveness of the air film hole when the hole 4 produces different displacements;

[0037] Figure 7(e) shows the spatial distribution of the air film effectiveness corresponding to the sampling points;

[0038] Figure 7(f) is the plane distribution diagram of the air film effectiveness corresponding to the sampling points;

[0039] Figure 8 The figures show the cold air coverage effects corresponding to the air film holes on the first separation line of the present invention and the air film holes on the arc line in the prior art under different blowing ratios;

[0040] Figure 9 The table below is a comparison of the average air film effectiveness of the air film holes on the first separation line of the present invention and the air film holes on the arc line in the prior art under different blowing ratios.

[0041] Figure 10 The cooling air coverage effect diagrams corresponding to the full coverage layout of the present invention and the full coverage layout in the prior art respectively;

[0042] Figure 11 The following is a comparison table of the surface average air film effectiveness of the full coverage layout of the present invention and the full coverage layout in the prior art.

[0043] Figure numerals: 100 - moving blade; 110 - first separation line; 111 - second separation line; 112 - third separation line; 120 - leakage flow; 130 - groove vortex near pressure side; 140 - near pressure side; 150 - near suction side; 160 - groove; 170 - air film hole. DETAILED DESCRIPTION

[0044] To make the above-mentioned objects, features, and advantages of the present invention more readily apparent, specific embodiments of the present invention are described in detail below with reference to the accompanying drawings. The following description sets forth numerous specific details to facilitate a full understanding of the present invention. However, the present invention can be implemented in many other ways than those described herein, and those skilled in the art may make similar modifications without departing from the scope of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0045] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like to indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0046] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of the technical features being referred to. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of the present invention, "plurality" means at least two, such as two, three, etc., unless otherwise specifically defined.

[0047] In the present invention, unless otherwise specified or limited, the terms "installed," "connected," "connect," "fixed," etc. should be understood in a broad sense. For example, they can refer to fixed connection, detachable connection, or integration; mechanical connection, electrical connection; direct connection, or indirect connection through an intermediate medium; internal communication between two components, or interaction between two components, unless otherwise specified. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on specific circumstances.

[0048] In the present invention, unless otherwise expressly specified or limited, when a first feature is "above" or "below" a second feature, it may mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediary. Furthermore, when a first feature is "above," "above," or "above" a second feature, it may mean that the first feature is directly above or diagonally above the second feature, or simply means that the first feature is at a higher level than the second feature. When a first feature is "below," "below," or "below" a second feature, it may mean that the first feature is directly below or diagonally below the second feature, or simply means that the first feature is at a lower level than the second feature.

[0049] It should be noted that when an element is referred to as being "fixed to" or "disposed on" another element, it may be directly on the other element or there may be an intermediate element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be an intermediate element. The terms "vertical," "horizontal," "upper," "lower," "left," "right," and similar expressions used herein are for illustrative purposes only and do not represent the only implementation methods.

[0050] See Figure 1 and Figure 2 An embodiment of the present invention provides a method for film holes in turbine blades, including a single-row hole layout method and a full-coverage layout method. Both the single-row hole layout method and the full-coverage layout method include the steps of determining the position of a first separation line 110, and sequentially arranging a plurality of film holes 170 on the first separation line 110. The first separation line 110 is the separation line position on the blade 100 under the design working conditions.

[0051] In this embodiment, the single-row hole layout method may be to set only one exhaust film hole 170 on the first separation line 110 of the rotor blade 100. The full-coverage layout method includes at least two exhaust film holes 170, one row of which is set on the first separation line 110 of the rotor blade 100.

[0052] Because the tip of the rotor blade 100 is generally a high-heat-load area, the film holes 170 at the tip of the rotor blade 100 can be arranged using the same layout as those used for turbine rotor blades. In actual turbine blade design, a certain gap is typically reserved between the tip of the rotor blade 100 and the turbine casing to prevent friction. This gap also creates fluid disturbance at the tip, generating a separation vortex at the tip of the rotor blade 100.

[0053] The separation line 110 is generated by the separation vortex, and the air film hole 170 is set on the separation line generated by the separation vortex under the design working conditions (that is, the first separation line 110). The cold air ejected from the air film hole 170 can be spread on the top of the moving blade 100 under the influence of the separation vortex, that is, the contact area between the cold air and the top of the moving blade 100 is increased, and the effectiveness of the air film is enhanced, so that a better cooling effect can be obtained.

[0054] Specifically, the position of the separation line can be obtained by computational fluid dynamics methods, oil flow experimental methods, inkblot experimental methods, etc.

[0055] For further information, see Figure 2 The moving blade 100 is a moving blade 100 having a groove 160 on the blade tip, and the first separation line 110 is a separation line generated by the groove vortex 130 near the pressure side when there is no cold air jet.

[0056] The rotor blades 100 with the grooves 160 include but are not limited to fully grooved blade top rotor blades, tail-opened grooved blade top rotor blades, blade top rotor blades combining grooves and winglets, and blade top rotor blades combining grooves and flat blade tops.

[0057] During the rotation of the turbine, the blade 100 has a near-pressure side 140 and a near-suction side 150. The film hole 170 is arranged on the separation line generated by the near-pressure side groove vortex 130 in the blade tip groove 160. The cold air ejected from the film hole 170 is sucked by the near-pressure side groove vortex 130 and the leakage flow 120, which weakens the kidney-shaped vortex strength generated by the cold air jet, allowing the cold air to spread to the maximum extent on the bottom surface of the groove 160. Figure 2 and Figure 3 , thus having a higher air film effectiveness.

[0058] In some embodiments, the full coverage layout method further includes the steps of determining the positions of the second separation line 111 and / or the third separation line 112, and sequentially disposing a plurality of film holes on the second separation line 111 and / or the third separation line 112. The second separation line 111 and the third separation line 112 are respectively two boundary lines of the separation line of the rotor blade under variable operating conditions.

[0059] In one embodiment, a plurality of air film holes are sequentially arranged on the second separation line 111 , and a plurality of air film holes are sequentially arranged on the third separation line 112 .

[0060] Through the sensitivity analysis of the separation line, when the blowing ratio, gap height, angle of attack, jet angle and other various working conditions change, under certain conditions, the strength and size of the near-pressure side groove vortex 130 will change, thereby causing the position of the separation line to move. When the position of the separation line moves, the cold air ejected from the air film hole 170 there is no longer affected by the combined action of the entrainment and leakage flow of the near-pressure side groove vortex 130, thereby seriously affecting the effectiveness of the air film. Therefore, the present application also proposes a second separation line 111 and a third separation line 112. The second separation line 111 refers to the boundary line of the separation line close to the suction side 150, and the third separation line 112 refers to the boundary line close to the pressure side 140. The second separation line 111 and the third separation line 112 are respectively located on both sides of the first separation line 110, see Figure 4 By arranging a plurality of air film holes 170 on the second separation line 111 and the third separation line 112, air film holes are always located on the separation lines under non-design working conditions, giving full play to the positive effect of the separation lines on the effectiveness of the air film.

[0061] In another embodiment, multiple air film holes may be sequentially arranged only on the second separation line 111 , or multiple air film holes may be sequentially arranged on the third separation line 112 .

[0062] Furthermore, the second separation line 111 is the separation line position at the maximum positive attack angle, and the third separation line 112 is the separation line position at the maximum blowing ratio.

[0063] Specifically, the separation line position at the maximum positive attack angle refers to the separation line position at the maximum positive attack angle when there is no cold air jet, and the separation line position at the maximum blowing ratio refers to the separation line position at the maximum blowing ratio under the air film holes 170 arranged on the mid-arc line.

[0064] After sensitivity analysis of the separation line, see Figure 5(a)-Figure 5(c), is the effect of different gap heights and blowing ratios on the separation line. When the gap height is less than the depth of the groove 160, the position of the separation line is significantly affected by the blowing ratio. At low blowing ratios, the position of the separation line is basically the same as the position when there is no cold air jet. At this time, the cold air jet has little effect on the groove vortex 130 near the pressure side. As the blowing ratio increases, the kinetic energy of the cold air increases, and the interaction between the groove vortex and the cold air jet is enhanced, which reduces the intensity of the groove vortex, resulting in a significant change in the position of the separation line. Referring to Figure 5(a), the separation line shifts toward the pressure side as the blowing ratio increases, and the maximum offset is 4 times the aperture (4d). Referring to Figures 5(b) and 5(c), when the gap height is greater than or equal to the depth of the groove 160, the position of the separation line is basically unaffected by the blowing ratio, and the maximum offset is one times the aperture. This is because as the gap height increases, the intensity of the groove vortex also increases. Therefore, for the same cold air jet, the ability of the groove vortex to resist the influence of the cold air jet is enhanced, and the separation line is insensitive to the blowing ratio. Therefore, when the gap height is greater than or equal to the depth of the groove 160, the position of the separation line close to the pressure side 140 can be obtained at the maximum blowing ratio, that is, Figure 4 The third separation line 112 position in.

[0065] See Figure 6(a)-Figure 6(e) When there is an angle of attack at the inlet, the initial inflow position of the leakage flow 120 will change, thereby affecting the formation of the near-pressure side groove vortex 130, and the separation line position will also change accordingly. Figure 6(a) to Figure 6(c) The influence of the angle of attack on the position of the separation line at different gap heights is shown respectively. Specifically, a positive angle of attack will cause the scoring line to migrate as a whole to the suction side, and a negative angle of attack will cause the scoring line to migrate to the pressure side. At the three gap heights, the positive angle of attack has a greater effect on the separation line, while the negative angle of attack has a smaller effect on the separation line. Figure 6 (d) and Figure 6 (e) respectively compare the effect of the gap height on the separation line when there is an angle of attack. For a positive angle of attack, as the gap height increases, the separation line gradually shifts toward the pressure side. When the gap height is greater than or equal to the depth of the groove 160, the position of the separation line is almost unaffected by the gap height. When there is a negative angle of attack, the position of the separation line is almost insensitive to the gap height. Therefore, when the gap height is greater than or equal to the depth of the groove 160, at the maximum positive angle of attack, it can be concluded that the position of the separation line close to the suction side 150 is Figure 4 The position of the second separation line 111 in .

[0066] In another embodiment, the full coverage layout method can also be to open two exhaust film holes on the first separation line and the near pressure side of the moving blade respectively, or to open two exhaust film holes on the first separation line and the near suction side of the moving blade respectively, or to open three exhaust film holes on the first separation line, the near pressure side of the moving blade and the near suction side of the moving blade at the same time.

[0067] In some embodiments, a single-row hole layout method is applicable to a rotor blade 100 operating only under design operating conditions. A full-coverage layout method is applicable to a rotor blade 100 operating under variable operating conditions. When the operating conditions are the design operating conditions, the position of the separation line does not change. Simply deploying a single exhaust film hole 170 on the separation line allows the cooling air to fully spread across the blade tip. When operating conditions change, the position of the separation line may change based on a sensitivity analysis of the separation line. Therefore, to further enhance the positive effects of the separation line, air film holes 170 are provided on the first separation line 110, the second separation line 111, and the third separation line 112.

[0068] For single row hole layout method, see Figure 8 Comparing the single-row hole layout of the present invention with the mid-camber layout having a higher effectiveness of the air film holes 170, it can be clearly seen from the cooling air coverage effect that the single-row hole layout of the present invention significantly increases the cooling air coverage on the blade top surface. Figure 9 It can be seen from the surface average air film effectiveness that the single-row hole layout of the present invention increases the average air film effectiveness of the blade top surface by 68.6% compared with the mid-arc arrangement when the blowing ratio M=0.5.

[0069] For full coverage layout methods, see Figure 10 , comparing the full coverage layout of the present invention with other full coverage layouts, it can be clearly seen from the cold air coverage effect that the full coverage layout of the present invention makes the blade top surface fully covered by cold air, see Figure 11 From the perspective of surface average air film effectiveness, the full coverage layout of the present invention increases the average air film effectiveness of the blade top surface by 24.3% compared with the existing full coverage layout.

[0070] The present invention's method for arranging film holes for turbine blades is applicable to blade tips of various geometric shapes. Based on the present invention, the positional layout of film holes 170 on the blade tips of the blades 100 can be directly determined, avoiding the extensive trial-and-error cooling layout adjustments required by existing design methods.

[0071] An embodiment of the present invention also provides a turbine blade 100, wherein an air flow channel is provided inside the blade 100, a groove 160 is provided on the top of the blade 100, the air flow channel and the groove 160 are connected through a plurality of air film holes 170, the blade 100 has a first separation line 110, and a plurality of air film holes 170 arranged in sequence are provided on the first separation line 110, and the first separation line 110 is the separation line position on the blade under the design working conditions.

[0072] The jet angle of the film holes 170 can be 90°, the aperture can be 1 mm, and the film holes 170 can be circular. Cold air enters the airflow channel, where it cools the main body of the rotor blade 100. It then passes through the film holes 170 and is ejected from the grooves 160. Providing the film holes 170 on the first separation line 110 ensures that the exhausted cold air covers the blade tip grooves 160 as much as possible, thus fully cooling the blade tip.

[0073] In some embodiments, the moving blade 100 also has a second separation line 111 and a third separation line 112. A plurality of air film holes are arranged in sequence on the second separation line 111 and / or the third separation line 112. The second separation line 111 and the third separation line 112 are respectively two boundary lines of the separation line of the moving blade under variable working conditions.

[0074] In one embodiment, a plurality of air film holes are sequentially arranged on the second separation line 111 , and a plurality of air film holes are sequentially arranged on the third separation line 112 .

[0075] When actually producing the blade, the first separation line 110 , the second separation line 111 and the third separation line 112 may be firstly carved on the top of the blade, and then the air film holes 170 may be opened on the first separation line 110 , the second separation line 111 and the third separation line 112 in sequence.

[0076] In this embodiment, when the rotor blade 100 is used under varying operating conditions, the position of the separation line may shift, thereby affecting the effectiveness of the air film. Therefore, a plurality of air film holes 170 are sequentially arranged on the first separation line 110, the second separation line 111, and the third separation line 112. This reduces the problem of reduced air film effectiveness caused by movement of the first separation line 110 due to varying operating conditions, thereby fully utilizing the positive effect of the first separation line 110 on air film effectiveness.

[0077] In another embodiment, multiple air film holes may be sequentially arranged only on the first separation line 110 and the second separation line 111 , or multiple air film holes may be sequentially arranged only on the first separation line 110 and the third separation line 112 .

[0078] Furthermore, the hole distance between any two adjacent air film holes 170 on the first separation line 110 and the hole distance between any two adjacent air film holes 170 on the second separation line 111 and / or the third separation line 112 are equal. The effectiveness of the air film can be improved by equidistant means. For the specific verification process, please refer to Figure 7(a)-Figure 7(f) .

[0079] Since the separation line affects the jet trajectory only in the front half of the blade, the five film holes 170 arranged along the middle arc line near the leading edge are arranged along the first separation line 110, while the positions of the other five film holes 170 remain unchanged, resulting in a new arrangement of film holes 170, see Figure 7(a). The five film holes 170 arranged along the first separation line 110 are labeled as holes 1 to 5, respectively. The distance between the centers of holes 1 and 2 is 7 times the aperture diameter, and the distance between the remaining holes is 10 times the aperture diameter. The displacement of holes 2, 3, and 4 is set as a variable, with movement of the holes toward the leading edge being negative displacement and movement toward the trailing edge being positive displacement. To prevent two holes from moving to the same position, the absolute maximum value of the positive and negative displacements is 4 times the aperture diameter, and the absolute value of the minimum displacement is 0.1 times the aperture diameter.

[0080] The Latin hypercube is used to sample the three variables and obtain 113 sample points. By performing full three-dimensional numerical simulation on the 113 sample points, the average air film effectiveness distribution on the blade top surface is obtained. Figure 7(b)-Figure 7(d) The figure shows the effects of hole 2, hole 3, and hole 4 on the air film effectiveness on the blade top surface. For hole 2, see Figure 7(b), it can be seen that the effectiveness decreases when hole 2 undergoes positive and negative displacement. When hole 2 remains in its original position, it has a higher air film effectiveness. See Figure 7(c), for hole 3, the air film effectiveness corresponding to different displacements shows that the air film effectiveness is basically insensitive to hole 3. See Figure 7(d), for hole 4, it can be clearly seen that the air film effectiveness distribution shows a linear distribution with the displacement of hole 4. The air film effectiveness increases with the increase of the positive displacement of hole 4, which shows that the air film effectiveness is more sensitive to hole 4.

[0081] Because the air film effectiveness is affected by the interaction between holes 2, 3, and 4, the results of the sampling points are displayed in a three-dimensional graph, see Figure 7(e). The value at the coordinate origin is the air film effectiveness of the baseline arrangement. When the hole spacing changes dramatically, the air film effectiveness drops sharply. Points with higher air film effectiveness after the hole spacing changes are generally near the coordinate origin. Among them, holes 2 and 3 basically do not move, and a positive displacement of hole 4 is conducive to an increase in air film effectiveness. The sampling points are numbered to obtain the air film effectiveness distribution corresponding to different sampling points, see Figure 7(f). The solid line represents the air film effectiveness corresponding to the baseline arrangement, and the solid points are sample points with higher air film effectiveness than the baseline arrangement. In other words, the air film effectiveness increased by up to 3.68% due to the change in hole spacing compared to the baseline arrangement. This shows that the equidistant arrangement of air film holes 170 arranged on the separation line has better air film effectiveness.

[0082] Furthermore, the hole distance between two adjacent air film holes 170 is 4-6 times the hole diameter. Specifically, when the hole distance between two adjacent air film holes 170 is 5 times the hole diameter, the air film effectiveness is higher.

[0083] The technical features of the above-mentioned embodiments can be combined arbitrarily. In order to make the description concise, not all possible combinations of the technical features in the above-mentioned embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0084] The above-described embodiments merely illustrate several implementations of the present invention, and while their descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent. It should be noted that a person skilled in the art would be able to make numerous variations and improvements without departing from the spirit of the present invention, all of which fall within the scope of protection of the present invention. Therefore, the scope of protection of the patent for this invention shall be determined by the appended claims.

Claims

1. A method for arranging film holes of turbine blades, characterized in that: The method includes a single-row hole layout method and a full-coverage layout method, both of which include the following steps: Determining a position of a first separation line, where the first separation line is a position of a separation line on the rotor blade under a design operating condition; Arrange a plurality of air film holes in sequence on the first separation line; The moving blade is a moving blade with a groove on the blade top, and the first separation line is the separation line generated by the groove vortex on the near-pressure side when there is no cold air jet; wherein, the moving blade with grooves includes a full-groove blade top moving blade, a groove blade top moving blade with a tail opening, a blade top moving blade with a combination of grooves and winglets, or a blade top moving blade with a combination of grooves and flat blade tops.

2. The method for arranging film holes of turbine blades according to claim 1, wherein the full coverage layout method further comprises the steps of: Determining the positions of a second separation line and / or a third separation line, wherein the second separation line and the third separation line are respectively two boundary lines of the separation line of the moving blade under variable operating conditions; A plurality of air film holes are sequentially arranged on the second separation line and / or the third separation line.

3. The method for arranging film holes of turbine blades according to claim 2, characterized in that: The second separation line is the separation line position at the maximum positive attack angle, and the third separation line is the separation line position at the maximum blowing ratio.

4. The method for arranging film holes of turbine blades according to claim 3, characterized in that: The separation line position at the maximum positive attack angle refers to the separation line position at the maximum positive attack angle when there is no cold air jet, and the separation line position at the maximum blowing ratio refers to the separation line position at the maximum blowing ratio under the air film holes arranged on the mid-arc line.

5. The method for arranging film holes of turbine blades according to claim 1, characterized in that: The single-row hole layout method is applicable to rotor blades operating only under design working conditions, and the full-coverage layout method is applicable to rotor blades operating under variable working conditions.

6. A turbine rotor blade, characterized in that: An air flow channel is provided inside the moving blade, a groove is provided on the top of the moving blade, the air flow channel is connected to the groove through a plurality of air film holes, the moving blade has a first separation line, a plurality of the air film holes are sequentially provided on the first separation line, wherein the first separation line is the separation line position on the moving blade under the design working conditions.

7. The turbine rotor blade according to claim 6, characterized in that: The moving blade also has a second separation line and a third separation line. A plurality of the air film holes are sequentially opened on the second separation line and / or the third separation line. The second separation line and the third separation line are respectively two boundary lines of the separation line of the moving blade under variable working conditions.

8. The turbine rotor blade according to claim 7, characterized in that: The hole distance between any two adjacent air film holes on the first separation line is equal, and the hole distance between any two adjacent air film holes on the second separation line and / or the third separation line is equal.

9. The turbine rotor blade according to claim 8, characterized in that: The distance between two adjacent air film holes is 4-6 times the hole diameter.

Images