A moving blade tip structure, a turbine device, and a gas turbine

Abstract

The present application relates to the technical field of gas turbine, in particular to a blade tip structure, a turbine device and a gas turbine. The blade tip structure comprises: a blade tip body, comprising a pressure side shoulder wall and a suction side shoulder wall, the pressure side shoulder wall and the suction side shoulder wall enclosing a blade tip groove; a rib structure, which is arranged in the blade tip groove along the direction of the blade tip mean camber line, so as to divide the blade tip groove into N+1 sub-groove structures, and each adjacent two sub-groove structures are not communicated with each other; wherein, the length of the sub-groove structure near the blade tip leading edge along the direction of the blade tip mean camber line is equal to the length of the rib structure; and a shoulder wall opening is arranged on the pressure side shoulder wall of at least one sub-groove structure near the blade tip trailing edge. The blade tip structure provided by the present application can reduce the fluctuation amplitude of the blade tip heat transfer coefficient, relieve the thermal fatigue of the blade tip material, and maintain the safe operation of the gas turbine turbine.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of gas turbine technology, in particular to a blade tip structure, a turbine device and a gas turbine. BACKGROUND

[0002] The groove-shaped blade tip is an important blade tip structure design for reducing blade tip leakage loss, and has been widely used in various modern gas turbine devices.

[0003] The existing groove-shaped blade tip, as shown in the original flat blade tip, establishes a groove structure in the middle of the blade tip, which is called a blade tip groove, and the shoulder wall around the blade tip is called the pressure side shoulder wall and the suction side shoulder wall according to the relative position of the blade pressure side and the suction side, as shown in Figure 1 The high-temperature gas in the pressure side enters the groove-shaped blade tip gap, and is no longer directly through the blade tip gap into the suction side cascade channel, but first enters the groove interior under the entrainment of the pressure side corner vortex and the scraping vortex in the groove, and passes through the blade tip gap in an "S" shape. The pressure side corner vortex in the groove is formed by the flow restriction of the pressure side shoulder wall, and the scraping vortex is formed by the relative motion of the turbine casing and the blade tip. The two vortexes rotate in opposite directions and jointly drive the blade tip gap leakage flow into the groove interior, change the original motion trajectory of the blade tip gap leakage flow, and thus reduce the blade tip leakage loss. However, the impact of high-temperature gas on the groove bottom surface will destroy the fluid boundary layer near the wall surface, enhance the local convective heat transfer, and cause serious thermal load on the blade tip wall surface. As shown in Figure 2 The static blade wake is a low-energy fluid shed from the static blade wall surface, and the dynamic blade periodically contacts the static blade wake during rotation. The low-energy fluid of the static blade wake affects the flow field structure around the dynamic blade, changes the pressure gradient between the pressure side and the suction side of the blade tip, and the blade tip gap leakage flow fluctuates under the action of the periodic pressure gradient, thereby changing the position and value of the high heat transfer coefficient area of the groove bottom surface and increasing the fluctuation amplitude of the blade tip heat transfer coefficient. Figure 3

[0004] Therefore, the fluctuation amplitude of the blade tip heat transfer coefficient of the existing groove-shaped blade tip is large, and there is an urgent need for a blade tip structure that can reduce the fluctuation amplitude of the blade tip heat transfer coefficient. SUMMARY

[0005] Therefore, the technical problem to be solved by the present application is to overcome the defect that the fluctuation amplitude of the blade tip heat transfer coefficient of the existing groove-shaped blade tip is large in the prior art, so as to provide a dynamic blade tip structure capable of reducing the fluctuation amplitude of the blade tip heat transfer coefficient.

[0006] To solve the above technical problems, the dynamic blade tip structure provided by the present application comprises: ​

[0007] A blade tip body, comprising a pressure side shoulder wall and a suction side shoulder wall, the pressure side shoulder wall and the suction side shoulder wall enclosing a blade tip groove;

[0008] A rib structure, the number of which is N, N rib structures are arranged in the blade tip mean camber direction and are spaced apart in the blade tip groove, one end of any rib structure is connected with the pressure side shoulder wall, and the other end is connected with the suction side shoulder wall, so as to divide the blade tip groove into N+1 sub-groove structures, and each adjacent two sub-groove structures are not connected with each other;

[0009] Wherein, the length of the sub-groove structure near the blade tip leading edge position in the blade tip mean camber direction is equal to the length of the rib structure; and at least one sub-groove structure near the blade tip trailing edge position is provided with a shoulder wall opening on the pressure side shoulder wall.

[0010] Optionally, the width of the shoulder wall opening is G, and G satisfies 2%·H≤G≤4%·H, wherein H is the height of the blade tip body.

[0011] Optionally, each rib structure is perpendicular to the blade tip mean camber.

[0012] Optionally, the shoulder wall opening is arranged at an upstream position of the pressure side shoulder wall of the sub-groove structure.

[0013] Optionally, the height of the rib structure is equal to the depth of the blade tip groove.

[0014] Optionally, the width of the pressure side shoulder wall and the suction side shoulder wall is equal to the width of the rib structure.

[0015] The application also provides a turbine device, comprising:

[0016] A turbine casing;

[0017] A turbine stator blade and a turbine rotor blade;

[0018] The turbine rotor blade comprises the blade tip structure as described above.

[0019] Optionally, a blade tip gap is arranged radially between the blade tip body and the turbine casing, and the blade tip gap is C, and C satisfies C=1%·H, wherein H is the height of the blade tip body.

[0020] Optionally, the pitch of the turbine stator blade is twice the pitch of the turbine rotor blade.

[0021] The application also provides a gas turbine, comprising a gas turbine body and the turbine device as described above.

[0022] The technical scheme of the present application has the following advantages:

[0023] 1. The blade tip structure provided by the present application, the rib structure is arranged in the tip groove along the direction of the middle camber line of the tip, so as to divide the tip groove into N+1 sub-groove structures, and each two adjacent sub-groove structures are not communicated with each other; the length of the sub-groove structure near the leading edge of the tip along the direction of the middle camber line of the tip is equal to the length of the rib structure; and at least one of the sub-groove structures near the trailing edge of the tip is provided with a shoulder wall gap on the pressure side shoulder wall; compared with the structure of the improved groove-shaped blade tip, the blade tip structure of the present application reduces the sensitivity of the pressure side corner vortex and the newly generated rib rear vortex to the pressure gradient on both sides of the tip, weakens the influence of the fluctuating pressure gradient on the vortex system structure in the tip groove, and reduces the fluctuation amplitude of the heat transfer coefficient of the tip bottom surface.

[0024] 2. The blade tip structure provided by the present application, the width of the shoulder wall gap is G, the width of the shoulder wall gap cannot be too small, otherwise the leakage flow from the shoulder wall gap is too low to reduce the rotation strength of the pressure side corner vortex in the groove, therefore the width G of the shoulder wall gap needs to satisfy G≥2%·H, wherein H is the height of the blade tip body; however, the width of the shoulder wall gap cannot be too large, otherwise the leakage flow is too fast, which easily increases the leakage loss of the tip, therefore the width G of the shoulder wall gap needs to satisfy G≤4%·H; the width G of the shoulder wall gap satisfies 2%·H≤G≤4%·H, on the one hand, the leakage flow from the shoulder wall gap can be ensured, so as to reduce the rotation strength of the pressure side corner vortex in the groove, and on the other hand, the leakage flow is prevented from being too fast, so as to reduce the leakage loss of the tip. BRIEF DESCRIPTION OF DRAWINGS

[0025] In order to more clearly illustrate the specific embodiments of the present application or the technical scheme in the prior art, the drawings needed to be used in the specific embodiments or the prior art description will be briefly introduced below. Obviously, the drawings in the following description are some embodiments of the present application, and other drawings can also be obtained by those skilled in the art without creative labor.

[0026] Figure 1 The structure diagram of the improved groove-shaped blade tip;

[0027] Figure 2 The structure diagram of the flow field in the cross section of the improved groove-shaped blade tip;

[0028] Figure 3Fig. 1 is a schematic diagram of the overall structure of the first stage blade of a turbine with a pre-modified grooved rotor blade tip;

[0029] Figure 4 Fig. 2 is a schematic diagram of the peripheral flow field structure of the pre-modified grooved rotor blade tip under the influence of the low-energy fluid in the stator wake;

[0030] Figure 5 Fig. 3 is a schematic diagram of the overall structure of the rotor blade tip structure of the present application;

[0031] Figure 6 Fig. 4 is a schematic diagram of the top view structure of the rotor blade tip structure of the present application; Figure 5 Fig. 5 is a schematic diagram of the side view structure of the rotor blade tip structure of the present application;

[0032] Figure 7 Fig. 6 is a schematic diagram of the vortex system structure in the tip groove of the rotor blade tip structure of the present application;

[0033] Figure 8 Fig. 7 is a meridional sectional view of the first stage blade cascade passage of the turbine device of the present application;

[0034] Figure 9 Fig. 8 is an enlarged view of A in Fig. 7; Figure 8

[0035] Figure 10 Fig. 9 is a comparison graph of the time fluctuation curves of the average heat transfer coefficient of the rotor blade tip structure of the present application and the pre-modified grooved rotor blade tip.

[0036] BRIEF DESCRIPTION OF THE DRAWINGS

[0037] 10, rotor blade tip body; 100, tip groove; 11, pressure side shoulder wall; 12, suction side shoulder wall;

[0038] 20, rib structure; 21, first rib; 22, second rib; 23, third rib; 24, fourth rib;

[0039] 30, sub-groove structure; 300, shoulder wall aperture; 301, first aperture; 302, second aperture; 31, first sub-groove; 32, second sub-groove; 33, third sub-groove; 34, fourth sub-groove; 35, fifth sub-groove;

[0040] 40, turbine housing;

[0041] 50, turbine stator blade;

[0042] 60, turbine rotor blade;

[0043] 70, rotor blade tip gap. DETAILED DESCRIPTION

[0044] ​The technical solutions of the present application will be described clearly and completely below with reference to the drawings. Obviously, the described embodiments are only some of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work fall within the scope of the present application.

[0045] In the description of the present application, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer" and the like indicate the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application. In addition, the terms "first", "second", "third" are only for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0046] In the description of the present application, it should be noted that unless otherwise explicitly specified and limited, the terms "mounting", "connecting", "connecting" should be understood broadly, for example, it can be fixedly connected, or it can be detachably connected, or integrally connected; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium; it can be the communication inside two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0047] In addition, the technical features involved in the different embodiments of the present application described below can be combined with each other as long as they do not conflict with each other.

[0048] Embodiment one

[0049] In combination Figures 5-10 As shown in the drawings, the blade tip structure provided by the embodiment includes:

[0050] The blade tip body 10 includes a pressure side shoulder wall 11 and a suction side shoulder wall 12, and the pressure side shoulder wall 11 and the suction side shoulder wall 12 form a blade tip groove 100;

[0051] The rib structure 20 is N in number, and N rib structures 20 are arranged in the blade tip middle arc direction and arranged in the blade tip groove 100, one end of any rib structure 20 is connected with the pressure side shoulder wall 11, and the other end is connected with the suction side shoulder wall 12, so as to divide the blade tip groove 100 into N+1 sub-groove structures 30, and each adjacent two sub-groove structures 30 are not communicated with each other;

[0052] The length of the sub-groove structure 30 near the leading edge of the blade tip in the direction of the middle camber line of the blade tip is equal to the length of the rib structure 20; and a shoulder wall gap 300 is formed in the pressure side shoulder wall 11 of at least one of the sub-groove structures 30 near the trailing edge of the blade tip.

[0053] It should be noted that, as shown in Figure 3 and Figure 4 , each stage of the gas turbine turbine contains a certain number of static blades and moving blades. The static blades are stationary components, and the moving blades are rotating components. The fluid boundary layer on the surface of the static blade separates at the trailing edge of the static blade and develops downstream to form a static blade wake. Compared with the high-temperature gas in the main flow, the static blade wake is a low-energy fluid. When the moving blade contacts the static blade wake, the flow field structure around the moving blade changes, and the absolute values of the pressures on the pressure side and the suction side of the moving blade fluctuate, thereby affecting the pressure gradient on both sides of the moving blade. The development trajectory of the static blade wake remains stationary, while the moving blade is in a rotating state. At different times, the position of the moving blade contacting the static blade wake is different, and the influence of the static blade wake on the flow field of the moving blade also varies. Since all the static blade wakes of the upstream static blades are basically similar, the moving blade can be considered to be affected by a periodic static blade wake. As shown in Figure 10 , for example, at time t1 and time t5, the relative positions between the moving blade and the first static blade and the second static blade are exactly the same, and at this time, the influence of the static blade wake on the moving blade also basically remains the same. As shown in Figure 1 and Figure 2 , before the improvement, the concave groove-shaped blade tip, the pressure side shoulder wall and the suction side shoulder wall on both sides of the blade tip groove act as sealing teeth in a labyrinth seal, inducing the leakage flow in the blade tip gap to form a clockwise rotating vortex in the blade tip groove; however, unlike the labyrinth seal, due to the relative motion between the moving blade tip and the turbine casing, the fluid attached to the surface of the turbine casing forms a counterclockwise rotating scraping vortex in the blade tip gap. The scraping vortex penetrates into the inside of the blade tip groove, extruding the original vortex in the groove to the vicinity of the pressure side corner vortex. Under the joint action of the pressure side corner vortex and the scraping vortex, the high-temperature gas maintains an “S” trajectory to enter the inside of the blade tip groove, washes the fluid boundary layer on the bottom surface of the groove, and forms a high heat transfer coefficient area. At the same time, due to the influence of the upstream static blade wake on the flow field around the moving blade, the pressure gradient between the pressure side and the suction side of the blade tip fluctuates periodically with time, and the position and strength of the scraping vortex and the pressure side corner vortex also change. The position and area of the high heat transfer coefficient area on the bottom surface of the groove present different characteristics at different times, and the concave groove-shaped blade tip before the improvement has the phenomenon of excessive fluctuation amplitude of the blade tip wall heat transfer coefficient.

[0054] The blade tip structure provided by the application aims to reduce the fluctuation amplitude of the unsteady heat exchange coefficient of the turbine blade tip. By arranging the rib structure 20 in the blade tip groove 100 and opening the shoulder wall gap 300 on the pressure side shoulder wall 11, the heat exchange characteristics of the high heat exchange coefficient area of the blade tip wall surface are changed, the fluctuation of the high heat exchange coefficient area of the blade tip wall surface caused by the change of the pressure gradient on both sides of the blade tip affected by the upstream static blade wake is reduced, and then the fluctuation amplitude of the average heat exchange coefficient change curve of the blade tip wall surface is reduced, the thermal fatigue of the blade tip material is relieved, and the safe operation of the gas turbine turbine is maintained.

[0055] It should be noted that, in order to facilitate better explanation and understanding of the application scheme, the convection heat exchange coefficient h is defined as follows (unit: W / (K·m 2 ):

[0056]

[0057] In the formula, q is the heat flux density of the blade tip wall surface (unit: W / m 2 ); T a is the fluid temperature near the blade tip wall surface (unit: K); and T w is the blade tip wall surface temperature (unit: K).

[0058] It should be noted that, in order to facilitate better explanation and understanding of the application scheme, please refer to Figure 5 and Figure 6 , in this embodiment, four rib structures 20 are taken as an example for description, the four rib structures 20 are arranged in the blade tip groove 100 along the blade tip mean camber line direction and are respectively denoted as a first rib 21, a second rib 22, a third rib 23 and a fourth rib 24, so as to divide the blade tip groove 100 into five sub-groove structures 30, which are respectively denoted as a first sub-groove 31, a second sub-groove 32, a third sub-groove 33, a fourth sub-groove 34 and a fifth sub-groove 35, and each adjacent two sub-groove structures 30 are not connected to each other, wherein the blade tip mean camber line refers to the camber line indicated by the lead line "gamma" in Figure 6 .

[0059] It should be noted that, please refer to Figure 9 , the blade tip body 10 includes a pressure side shoulder wall 11 and a suction side shoulder wall 12, and the pressure side shoulder wall 11 and the suction side shoulder wall 12 enclose the blade tip groove 100; please refer to Figure 7As shown, N rib structures 20 are arranged in the tip groove 100 along the middle camber line γ direction, one end of any rib structure 20 is connected with the pressure side shoulder wall 11, and the other end is connected with the suction side shoulder wall 12, so as to divide the tip groove 100 into N+1 sub-groove structures 30, and each two adjacent sub-groove structures 30 are not communicated with each other, so that the pressure side corner vortex formed in each sub-groove structure 30 is blocked by the rib structure 20 and cannot move and develop into the downstream sub-groove structure 30, and the rotation intensity cannot be further improved. Still referring to Figure 7 As shown, in the first sub-groove 31, the tip gap leakage flow enters the tip groove 100 from the pressure side shoulder wall 11 and the suction side shoulder wall 12 respectively, so that the pressure side corner vortex cannot be formed; in the second sub-groove 32 and the third sub-groove 33, the rib rear vortex is formed near the rib downstream of the rib, and the pressure side corner vortex and the rib rear vortex are perpendicular to each other, and the rotation intensity is small; in the fourth sub-groove 34 and the fifth sub-groove 35, due to the short length of the upstream rib, the rib rear vortex is difficult to form downstream of the rib, and at this time, the pressure side corner vortex in the groove has high intensity, and the shoulder wall opening 300 is arranged at the upstream position of the pressure side shoulder wall of the fourth sub-groove 34 and the fifth sub-groove 35, please refer to Figure 5 and Figure 7 As shown, in the fourth sub-groove 34, the first opening 301 is arranged at the upstream position of the pressure side shoulder wall, and in the fifth sub-groove 35, the second opening 302 is arranged at the upstream position of the pressure side shoulder wall, so that the fluid directly enters the groove from the shoulder wall opening 300, thereby destroying the formation of the pressure side corner vortex; the height of the rib structure 20 is equal to the depth of the tip groove 100, that is, the height of the rib structure 20 is equal to the height of the shoulder wall, so that the scraping vortex is blocked by the rib structure 20 and cannot enter the inside of the tip groove 100, and the fluid on the bottom surface of the groove is no longer subjected to the entrainment and destructive effect of the scraping vortex, and in summary, compared with the structure of the groove-shaped blade tip before improvement, the blade tip structure of the present application reduces the sensitivity of the pressure side corner vortex and the newly generated rib rear vortex to the pressure gradient on both sides of the blade tip, weakens the influence of the fluctuating pressure gradient on the vortex system structure in the tip groove, and reduces the fluctuation amplitude of the heat transfer coefficient on the blade tip bottom surface.

[0060] Optionally, N rib structures 20 are arranged in the tip groove 100 along the middle camber line direction at equal intervals.

[0061] It should be noted that, in order to facilitate better illustration and understanding of the present application, the embodiment is described based on a first stage moving blade of a certain high-pressure turbine; however, in the process of specific implementation and application, due to different types of gas turbines, the shape of the turbine moving blade tip is different from that of the certain high-pressure turbine moving blade tip described in the embodiment, and the geometric design in the present application cannot be blindly followed. When the rib structure 20 described in the present application is arranged in the other turbine tip groove, firstly, the required number of rib structures 20 needs to be determined, and the length of the shoulder wall of the sub-groove structure 30 in the middle of the tip divided by the rib structure 20 and the length of the rib structure 20 corresponding to the sub-groove structure 30 are substantially equal, so that the pressure side corner vortex in the sub-groove structure 30 and the rib rear vortex cannot be fully developed, the rotation strength of the pressure side corner vortex and the rib rear vortex is reduced, and at the same time, due to the fact that the scraping vortex is limited by the rib structure 20 to the position above the sub-groove structure 30, it is difficult to act on the fluid near the groove bottom surface, so that the tip wall surface is difficult to have a high heat transfer coefficient area; when the axial length of the sub-groove structure 30 near the trailing edge of the tip is much greater than the length of the rib structure 20 corresponding to the sub-groove structure 30, the shoulder wall opening 300 is additionally arranged at the position of the pressure side shoulder wall of the sub-groove structure 30 close to the upstream rib structure 20, so that the fluid directly enters the tip groove from the shoulder wall opening 300, and then the formation of the pressure side corner vortex is destroyed. Preferably, the width of the shoulder wall opening 300 is substantially twice the depth of the tip groove, so that the fluctuation range of the tip heat transfer coefficient is minimum or close to minimum.

[0062] Specifically, the width of the shoulder wall opening 300 is G, and G satisfies 2%·H≤G≤4%·H, wherein H is the height of the moving blade tip body 10.

[0063] It should be noted that, as shown in Figure 5 The width of the shoulder wall opening 300 cannot be too small, otherwise the leakage flow rate entering from the shoulder wall opening 300 is too low, which cannot reduce the rotation strength of the pressure side corner vortex in the groove, and therefore the width G of the shoulder wall opening 300 needs to satisfy G≥2%·H, wherein H is the height of the moving blade tip body 10; however, the width of the shoulder wall opening 300 cannot be too large, otherwise the leakage flow rate is too fast, which easily increases the leakage loss of the tip, and therefore the width G of the shoulder wall opening 300 needs to satisfy G≤4%·H, wherein H is the height of the moving blade tip body 10; in summary, the width G of the shoulder wall opening 300 satisfies 2%·H≤G≤4%·H, which can on the one hand guarantee the leakage flow rate entering from the shoulder wall opening 300, thereby reducing the rotation strength of the pressure side corner vortex in the groove, and on the other hand avoid the leakage flow rate being too fast, thereby reducing the leakage loss of the tip.

[0064] Specifically, each rib structure 20 is perpendicular to the middle camber line of the blade tip.

[0065] It should be noted that each rib structure 20 should be as perpendicular as possible to the middle camber line of the blade tip, so that the pressure side corner vortex and the rib back vortex are perpendicular to each other, which is conducive to inhibiting the development of the pressure side corner vortex.

[0066] Specifically, the shoulder wall gap 300 is arranged at an upstream position of the pressure side shoulder wall 11 of the sub-slot structure 30.

[0067] Specifically, the height of the rib structure 20 is equal to the depth of the blade tip groove 100.

[0068] Optionally, the height of the rib structure 20 and the depth of the blade tip groove 100 are both S, and S satisfies S=2%·H.

[0069] It should be noted that the height of the rib structure 20 is M, and M satisfies M=S, wherein S is the depth of the blade tip groove 100, so that the height of the rib structure 20 is equal to the height of the shoulder wall, so that the scraping vortex is blocked by the rib structure 20 and cannot enter the inside of the blade tip groove 100, so that the concave groove bottom fluid is no longer subjected to the entrainment and damage effect of the scraping vortex.

[0070] Specifically, the width of the pressure side shoulder wall 11 and the suction side shoulder wall 12 is equal to the width of the rib structure 20.

[0071] Optionally, the width of the pressure side shoulder wall 11 and the suction side shoulder wall 12 is equal to the width of the rib structure 20, so as to facilitate processing and forming.

[0072] Optionally, the width of the rib structure 20 is L, and L satisfies L=1%·H.

[0073] Please refer to Figure 7 and Figure 10As shown, the technical principle of the blade tip structure of the present application is described as follows: first, different from the pressure side corner vortex extending from the front edge to the tail edge of the groove structure of the previous groove-shaped blade tip, the pressure side corner vortex is dispersed in the second sub-groove 32 and the third sub-groove 33, and the rib rear vortex close to the rib structure 20 is differentiated by setting the rib structure 20 and the shoulder wall gap 300. At this time, the pressure side corner vortex and the rib rear vortex are not fully developed, and the rotation strength is low. At the same time, since the scraping vortex is limited to the position above the groove by the rib, it is difficult to act on the fluid near the groove bottom surface, so that the blade tip wall surface cannot exist in the high heat exchange coefficient area. Secondly, due to the fully developed pressure side corner vortex and scraping vortex in the blade tip groove of the previous groove-shaped blade tip, when the pressure gradient on both sides of the blade tip fluctuates, the rotation strength and position of the pressure side corner vortex and the scraping vortex will change dramatically with the pressure gradient, and the distribution of the blade tip heat exchange coefficient presents obvious periodic non-steady-state characteristics. While the blade tip structure of the present application, the scraping vortex cannot enter the inside of the blade tip groove, so its rotation strength and position change cannot affect the groove bottom surface; and the pressure side corner vortex is not fully developed in each sub-groove structure 30, and the fluctuation caused by the influence of the pressure gradient fluctuation on both sides of the blade tip is always at a low level, so the periodic fluctuation of the heat exchange coefficient distribution on the groove bottom surface with time is not obvious, which is in sharp contrast to the traditional groove-shaped blade tip. Please refer to Figure 10 As shown, Figure 10 The average heat exchange coefficient fluctuation curve comparison diagram of the blade tip structure of the present application and the previous groove-shaped blade tip of the turbine is shown, and the comparison result shows that the average heat exchange coefficient curve of the blade tip structure of the present application is better than that of the previous groove-shaped blade tip in terms of absolute value and fluctuation amplitude, which proves the practicability of the blade tip structure of the present application in reducing the non-steady-state heat exchange coefficient fluctuation amplitude of the turbine blade tip.

[0074] Example two

[0075] Please refer to Figure 8 and Figure 9 As shown, the turbine device provided by the present embodiment comprises:

[0076] A turbine casing 40;

[0077] A turbine stator blade 50 and a turbine rotor blade 60;

[0078] The turbine rotor blade 60 comprises the blade tip structure as described above.

[0079] Specifically, the blade tip body 10 and the turbine casing 40 are radially spaced apart and form a blade tip gap 70, and C satisfies C = 1% H, wherein H is the height of the blade tip body 10.

[0080] Specifically, the pitch of the turbine stator blade 50 is twice the pitch of the turbine rotor blade 60.

[0081] Embodiment Three

[0082] The present embodiment provides a gas turbine comprising a gas turbine body and a turbine device as described above.

[0083] Obviously, the above-mentioned embodiment is only an example for clearly illustrating, but not a limitation to the embodiments. Based on the above description, other different forms of changes or variations can be made by those skilled in the art. Here, it is not necessary and also impossible to enumerate all the embodiments. The obvious changes or variations derived therefrom are still within the protection scope of the present application.

Claims

1. A moving blade tip structure, characterized in that, include: The blade tip body (10) includes a pressure side shoulder wall (11) and a suction side shoulder wall (12), which together form a blade tip groove (100). The number of rib structures (20) is N. The N rib structures (20) are spaced apart in the blade tip groove (100) along the mid-arc direction of the blade tip. One end of any rib structure (20) is connected to the pressure side shoulder wall (11), and the other end is connected to the suction side shoulder wall (12) to divide the blade tip groove (100) into N+1 sub-groove structures (30). Each two adjacent sub-groove structures (30) are not connected to each other. Among them, the length of the sub-groove structure (30) near the leading edge of the blade tip along the mid-arc direction of the blade tip is equal to the length of the rib structure (20); at least one of the sub-groove structures (30) near the trailing edge of the blade tip has a shoulder wall notch (300) on the pressure side shoulder wall (11). The width of the shoulder wall notch (300) is G, which satisfies 2%·H≤G≤4%·H, where H is the height of the moving blade tip body (10); The shoulder wall notch (300) is located upstream of the pressure side shoulder wall (11) of the sub-slot structure (30).

2. The moving blade tip structure according to claim 1, characterized in that, Each of the rib structures (20) is perpendicular to the mid-arc line of the blade tip.

3. The moving blade tip structure according to claim 1, characterized in that, The height of the rib structure (20) is equal to the depth of the blade tip groove (100).

4. The moving blade tip structure according to any one of claims 1-3, characterized in that, The widths of the pressure side shoulder wall (11) and the suction side shoulder wall (12) are equal to the width of the rib structure (20).

5. A turbine device, characterized in that, include: Turbine casing (40); Transparent static blade (50) and transverse translational blade (60); The turbine blade (60) includes the blade tip structure as described in any one of claims 1-4 above.

6. The turbine apparatus according to claim 5, characterized in that, The moving blade tip body (10) and the turbine casing (40) are arranged radially to form a moving blade tip gap (70), the moving blade tip gap (70) is C, C satisfies C=1% ·H, where H is the height of the moving blade tip body (10).

7. The turbine apparatus according to claim 5 or 6, characterized in that, The pitch of the transverse blade (50) is twice the pitch of the transverse blade (60).

8. A gas turbine, characterized in that, include: The gas turbine body, and the turbine apparatus as described in any one of claims 5-7 above.

Images