High-efficiency cooling outer ring basic element structure adapting to mainstream pressure and temperature changes

Abstract

The application discloses a high-efficiency cooling outer ring basic element structure suitable for adapting to mainstream pressure and temperature changes, which comprises an impingement orifice plate, an air film orifice plate and an impingement throttling cavity.

Description

Technical Field

[0001] This invention relates to the field of thermal protection for aero-engines, and more particularly to a highly efficient cooling outer ring structure that adapts to mainstream pressure and temperature changes. Background Technology

[0002] The turbine outer ring is located at the tip of the turbine blades. It forms the main flow channel through multiple discrete circumferential structures arranged in a ring shape. Its primary purpose is to shape the flow path of the turbine blades to ensure that the blades achieve their design objectives. Its position within the engine is as follows: Figure 1 As shown.

[0003] Besides forming the main flow channel for the turbine blades, the turbine outer ring also requires compressor bleed air for cooling due to the harsh working environment. Located downstream of the guide vane's critical interface, the cool air flowing into the main flow channel through the turbine outer ring is generally considered not to contribute to power. To improve the performance of existing engines, the turbine outer ring needs to achieve optimal cooling with minimal cool air loss. Therefore, its cooling mechanism is primarily a combined impingement-film cooling system. Figure 2 As shown, its internal flow path is: air supply chamber inlet - air inlet chamber - impact orifice plate - impact chamber - air film orifice plate - main flow channel.

[0004] refer to Figure 2 The schematic diagram shown is of a prior art turbine outer ring. For the prior art turbine outer ring, the cold air from the compressor first enters the intake chamber 102 located on the impact orifice plate through the intake port 101 on the fixed ring, and then enters the impact chamber 104 through the impact port 109 located on the impact orifice plate 103 for the first step of cooling, namely impact cooling: the cold air flowing out of the impact port 109 impacts the film orifice plate 105 at a high speed, forming a local strong cooling effect zone. Through multiple discrete impact ports, multiple local strong cooling effect zones are covered on the entire upper surface of the film orifice plate 105, thereby enhancing the average cooling effect on the entire upper surface of the film orifice plate 105; then, it flows into the main flow channel 106 through the film orifice 107 located on the left side of the film orifice plate 105 for the second step of cooling, namely film cooling: the cold air in the impact chamber 104 flows towards the front edge through the film orifice 107 ( Figure 2 Left side of the middle), posterior edge ( Figure 2 (Right side of the center), bottom surface, and both circumferential sides. For composite cooling, film cooling is significantly more effective than impact cooling. Therefore, the design of the outer ring structure requires precise design of the film cooling hole layout to achieve optimal film coverage.

[0005] As engine performance approaches its limits, the engine becomes increasingly sensitive to the cooling air inside the air system, and the restrictions on the amount of bleed air in the air system also gradually increase.

[0006] For the turbine outer ring, due to its unique location, the outflow boundary of the film hole is the main flow passage where the turbine working blade is located. The work of the turbine working blade causes a large pressure gradient and temperature gradient along the main flow direction. The axial along-the-way pressure distribution is shown in Figure 3 The axial along-the-way heat exchange temperature distribution is shown in Figure 4 , which is defined as the ratio of the total temperature inside the main flow passage along the axial direction to the inlet total temperature.

[0007] The impingement cavity is a chamber with uniform temperature and pressure, so under a fixed bleed air flow, for the turbine outer ring film hole, it is equivalent to an inlet pressure and temperature fixed in the axial direction, and the outlet pressure and temperature gradually decrease along the axial direction.

[0008] For the leading edge hole in the film hole, the inlet and outlet pressure ratio is small, which is the most difficult part to flow in the entire film hole plate, and the temperature at the location of the leading edge hole is the highest in the along-the-way heat exchange temperature, and the largest cold air flow is needed to cool this part. For the trailing edge hole in the film hole, the inlet and outlet pressure ratio is the largest, which is the easiest part to flow in the entire film hole plate, and the temperature at the location of the trailing edge hole is the lowest in the along-the-way heat exchange temperature, which is the part with the smallest demand for cold air in the entire film hole row.

[0009] For the film hole row on the bottom surface of the entire outer ring structure, the along-the-way flow demand is a gradually decreasing process. When the inlet pressure and temperature are fixed along the way, and the outlet pressure and temperature exist a large drop pressure gradient along the way, the along-the-way film hole row flow area should be gradually reduced. At the same time, since the blowing ratio and the inlet and outlet pressure ratio are related, the larger the inlet and outlet pressure ratio, the larger the blowing ratio. The cooling effect of a single film hole is not a linear relationship with the increase of the blowing ratio, but a first increase and then a decrease relationship. When the blowing ratio is large, the film outflow will rush out of the boundary layer on the surface of the outer ring, so that the film cannot form effective coverage on the surface, thereby greatly reducing the film cooling effect. At the same time, due to the small flow required by the trailing edge hole, a small film hole flow area is caused under a large pressure ratio, and under the condition of limited hole diameter, the number of film holes is greatly reduced, and the film basically does not have good coverage effect.

[0010] At present, most of the turbine outer ring structures are impact-film composite cooling structures (as shown in Figure 5 In addition, it also includes the impact-turbulence-film cooling structure in the existing cooling mode (as shown in Figure 6The impact cavities are all in a large cavity, and the flow of the leading edge holes on the film hole plate is extremely low under the flow guiding effect of the trailing edge holes, the film covering effect is extremely poor, and in order to achieve sufficient cooling, the overall cold air volume needs to be increased, thereby reducing the performance of the whole machine. For this case, the prior art also provides a form of separate cavity gas supply, as shown in Figure 7 The outer ring is divided into multiple chambers along the length, and the pressure and temperature in each separate cavity are basically uniform, but the pressure change in each impact cavity along the length is synchronized with the main flow pressure change, which to some extent solves the problem of pressure change along the length, but for the temperature change along the length, the same temperature cold air is basically used to correspond to the main flow gas (the main flow gas refers to the gas flowing through the main flow passage of the engine, and the main flow side of the turbine outer ring, see Figure 4 the temperature distribution along the length in Figure 8 The utilization rate of the cold air is not sufficient, because the trailing edge cools the main flow gas at the lowest temperature by using low-temperature cold air, and under the same inlet and outlet pressure ratio and the same film hole area, the lower the inlet temperature, the greater the real flow. That is, under the same flow, the lower the inlet temperature, the smaller the flow area required, and under the same film hole diameter, the fewer the number of film holes, and the worse the film covering effect. Therefore, in the cooling design of a turbine outer ring with large thickness, the limited cooling effect improvement due to the decrease of cold air temperature is affected by the large cooling loss due to the decrease of film covering effect.

[0011] There is a need in the art for a cooling ring structure that can solve the above problems, reduce cold air loss and improve cooling efficiency under the condition of providing appropriate cold air flow.

[0012] To solve the above problems, according to the embodiments of the present application, a high-efficiency cooling outer ring basic structure is provided, which can adapt to the changes of the main flow pressure and temperature, and can fully adapt to the changes of the main flow pressure and temperature under the condition that there is a large pressure gradient in the main flow interface, so as to realize film covering of the main flow side wall surface with less cold air and enhance the cooling effect. SUMMARY

[0013] According to the embodiments of the present application, a high-efficiency cooling outer ring basic structure is provided, which can adapt to the changes of the main flow pressure and temperature, and can fully adapt to the changes of the main flow pressure and temperature under the condition that there is a large pressure gradient in the main flow interface, so as to realize film covering of the main flow side wall surface with less cold air and enhance the cooling effect.

[0014] According to the embodiment of the present application, there is provided a high-efficiency cooling outer ring basic element structure adapted to changes in main flow pressure and temperature, characterized by comprising: an impingement orifice plate including an impingement orifice formed to penetrate the impingement orifice plate at a leading edge portion; a film hole plate including a door-wall structure formed in an axial direction on an upper surface thereof, a leading edge hole formed at a leading edge portion of the film hole plate, film holes formed at a middle portion of the film hole plate, and a trailing edge hole formed at a trailing edge portion of the film hole plate, the film holes being located between the door-wall structures; and an impingement throttle cavity formed by a space between the impingement orifice plate and the film hole plate after the impingement orifice plate and the film hole plate are combined, the space of the impingement throttle cavity being divided in the axial direction by the door-wall structures.

[0015] Optionally, the door-wall structure includes: doors formed in pairs on the upper surface of the film hole plate at positions on both sides in a lateral direction of the film hole plate, a gap for allowing a flow of air to pass between the doors; and walls formed on the upper surface of the film hole plate at a middle position in the lateral direction of the film hole plate, leaving gaps for allowing a flow of air to pass on both sides in the lateral direction thereof; wherein the doors and the walls are distributed in the axial direction at intervals on the film hole plate.

[0016] Optionally, the door-wall structure is arranged to cover a width of a blade of a turbine in the axial direction and a forward and rearward extension of 2 mm thereof in the axial direction.

[0017] Optionally, the impingement orifice plate and the film hole plate are integrally cast or are separately cast and then welded together.

[0018] Optionally, the impingement orifice plate has a bend at the leading edge portion, and the impingement orifice formed to penetrate the impingement orifice plate is inclined forward at the bend.

[0019] Optionally, the film holes are formed to penetrate the film hole plate at an inclined angle.

[0020] Optionally, the film holes are formed to penetrate the film hole plate vertically.

[0021] Optionally, a plurality of the high-efficiency cooling outer ring basic element structures are arranged in an array to form a turbine outer ring, constituting a main flow passage around a turbine blade in an engine.

[0022] Compared with the existing commonly used outer ring scheme, the cooling outer ring basic structure provided by the embodiment of the present application can realize "super cooling" of the leading edge through the cooperation of the large flow impact and the film hole at the leading edge with high temperature, which greatly reduces the gas consumption of the leading edge. At the bottom surface of the outer ring and the trailing edge part, due to the limitation of processing, the existing commonly used outer ring scheme cannot better utilize the gas film and cannot well control the flow of the trailing edge, while the outer ring provided by the embodiment of the present application is designed based on the method of along-the-way pressure control and gas film control, which can better control the along-the-way flow, and thus enhance the controllability of the gas film. For the trailing edge film hole row of the film hole, due to the large inlet and outlet pressure ratio and high blowing, it is difficult to achieve an optimal blowing ratio design, and thus more cooling gas is needed, and the door wall structure provided by the embodiment of the present application can control the flow area of the film hole and thus control the blowing ratio of each row of film holes, so as to achieve the optimal blowing ratio matching. In the process of multiple state changes, the change of expansion ratio will cause the change of along-the-way pressure gradient, and the existing scheme is sensitive to such change. If the expansion ratio increases, more cooling gas will flow to the trailing edge, and less cooling gas will flow to the leading edge, which will make the temperature level of the outer ring worse. Figure 12 As shown in FIG. 8, the temperature level is deteriorated.

[0023] The along-the-way temperature in the impact throttling cavity provided by the embodiment of the present application gradually rises from the leading edge to the trailing edge, which can correspond to the gradual decrease of the temperature on the mainstream side, that is, the cooling gas with high quality is used for cooling the position with high cooling demand, and the cooling gas with low quality is used for cooling the position with low cooling demand, so as to realize the step-by-step utilization of the along-the-way capacity and reduce the loss of cooling gas; at the same time, the along-the-way temperature rise can ensure that the area of the trailing edge film hole is relatively larger than that of the cavity gas supply structure, so that more film hole rows can be arranged when the film hole diameter is fixed, and better film covering effect can be obtained.

[0024] Other apparatuses, devices, systems, methods, features and advantages of the present application will be or will become apparent to one with skill in the art upon examination of the following figures and detailed description. It is intended that all such additional systems, methods, features and advantages be included within the scope of the present application, and be protected by the following claims. BRIEF DESCRIPTION OF DRAWINGS

[0025] The present application can be better understood with reference to the following drawings. The components in the drawings should not be considered as being to scale, emphasis instead being placed on illustrating the principles of the present application.

[0026] Figure 1is a schematic view of a prior art turbine outer ring assembly in an engine.

[0027] Figure 2 is a schematic view of a prior art turbine outer ring cooling.

[0028] Figure 3 is a schematic view of a prior art turbine outer ring cooling pressure distribution at the main flow side boundary.

[0029] Figure 4 is a schematic view of a prior art turbine outer ring cooling temperature distribution at the main flow side boundary.

[0030] Figure 5 is a schematic view of a prior art impingement-film cooling element and flow condition.

[0031] Figure 6 is a schematic view of a prior art impingement-film cooling element and flow condition.

[0032] Figure 7 is a schematic view of a split cavity fed turbine outer ring structure composed of an array of prior art outer ring elements.

[0033] Figure 8 is a schematic view of a split cavity fed turbine outer ring structure of the prior art under main flow condition.

[0034] Figure 9a is a side view of a high efficiency cooling outer ring element adapted to main flow pressure and temperature variations according to an embodiment of the present invention.

[0035] Figure 9b is a perspective view of a high efficiency cooling outer ring element adapted to main flow pressure and temperature variations according to an embodiment of the present invention.

[0036] Figure 10 is a schematic view of a door wall structure inside the impingement restriction cavity of a film hole plate in a high efficiency cooling outer ring element adapted to main flow pressure and temperature variations according to an embodiment of the present invention.

[0037] Figure 11 is a schematic view of a film hole along path distribution in a film hole plate in a high efficiency cooling outer ring element adapted to main flow pressure and temperature variations according to an embodiment of the present invention.

[0038] Figure 12 is a schematic view of outer ring cooling gas re-distribution after inlet flow reduction according to an embodiment of the present invention.

[0039] BRIEF DESCRIPTION OF DRAWINGS

[0040] 101 - inlet hole in prior art outer ring structure

[0041] 102-Intake chamber in existing outer ring structure

[0042] 103-Impact plate in existing outer ring structure

[0043] 104 - Impact cavity in existing outer ring structure

[0044] 105 - Existing outer ring structure with air film perforated plate

[0045] 106 - Main channel gap in existing outer ring structure

[0046] 107 - Existing outer ring structure with air film pores

[0047] 108-Turbine working blade

[0048] 109 - Impact holes in existing outer ring structures

[0049] 201-Impact plate

[0050] 202-Impact Throttling Chamber

[0051] 203-Air Film Perforated Plate

[0052] 204-Impact Hole

[0053] 205-Door and Wall Structure

[0054] 206-leading edge hole

[0055] 207-Air film pore

[0056] 208-Rear edge hole

[0057] 209-door

[0058] 210-wall Detailed Implementation

[0059] Exemplary embodiments of the present disclosure will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure may be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided to enable a more thorough understanding of the present disclosure and to fully convey its scope to those skilled in the art. It should be noted that, unless otherwise stated, the technical or scientific terms used in this invention should be understood in their ordinary sense by those skilled in the art to which this invention pertains.

[0060] The following is a reference appendix Figures 9a to 11 This paper provides a detailed description of a highly efficient cooling outer ring basic structure adapted to changes in mainstream pressure and temperature according to an embodiment of the present invention. Figure 9a This is a side view of the outer ring basic structure according to an embodiment of the present invention. Figure 9bThis is a perspective view of the outer ring basic structure according to an embodiment of the present invention. Figure 10 This is a schematic diagram of the door-wall structure inside the impact throttling chamber of an air film orifice plate according to an embodiment of the present invention. Figure 11 This is a schematic diagram of the distribution of air film pores along the path in an air film perforated plate according to an embodiment of the present invention.

[0061] According to an embodiment of the present invention, a high-efficiency cooling outer ring basic structure adapted to changes in mainstream pressure and temperature includes: an impact orifice plate 201, the impact orifice plate 201 having a bend at its leading edge, wherein an inclined impact hole 204 is formed penetrating the impact orifice plate 201; a film gas orifice plate 203, including a gate wall structure 205 formed on its upper surface, a leading edge hole 206 formed at the leading edge of the film gas orifice plate 203, a film gas orifice 207 formed in the middle of the film gas orifice plate 203, and a trailing edge hole 208 formed at the trailing edge of the film gas orifice plate 203, the film gas orifice 207 being located between the gate wall structures 205; and an impact throttling cavity 202, which is formed by the space between the impact orifice plate 201 and the film gas orifice plate 203 after they are combined, the space of the impact throttling cavity 202 being axially separated by the gate wall structure 205. Optionally, the door 209 and wall 210 of the door-wall structure 205 can adopt any suitable shape as needed, such as a rectangular structure, a racetrack-shaped structure (semi-circular ends and a rectangular middle section), etc. (Reference) Figure 9a The impact orifice plate 201 has a bend at its leading edge, where an impact hole 204 is formed. This reduces the relative angle between the impact hole 204 and the impact orifice plate 201, thus lowering the machining difficulty of the impact hole 204. Optionally, a leading edge hole 206 is formed horizontally forward at the leading edge of the film gas orifice plate 203. Alternatively, a trailing edge hole 208 is formed horizontally rearward at the trailing edge of the film gas orifice plate 203.

[0062] like Figure 9a As shown, the impact hole 204 allows air to enter the impact throttling chamber 202 from its leading edge, and the air intake angle of the impact hole 204 can be tilted to the left. Figure 2 Compared to the existing full-impact perforated plate shown, the advantage of the impact hole 204 according to the embodiment of the present invention is that it ensures efficient cooling of the outer ring at the high mainstream temperature leading edge by providing a large flow of cold air impact, while reducing the amount of film cooling air required at the leading edge.

[0063] In an alternative embodiment, the door-wall structure 205 can include doors 209 formed in pairs on the upper surface of the perforated plate 203 at both lateral sides of the perforated plate 203 with a gap between the doors 209 for air flow; and walls 210 formed on the upper surface of the perforated plate 203 at the middle of the perforated plate 203 with a gap on both sides for air flow, wherein the doors 209 and walls 210 are distributed alternately on the perforated plate 203. As shown in Figure 10 the door-wall structure 205 is equivalent to a door 209 in front of and a wall 210 behind every two columns. The two columns in front and behind are staggered, the two columns in front are doors 209 with a gap between them for air flow, and the two columns behind are walls 210 which are located on the fluid flow path from the gap between the doors 209 in front, forming a wall. Further behind, the doors 209 and walls 210 are arranged alternately in the above manner. Such staggered columns are referred to as the door-wall structure 205. The structure of the doors 209 can achieve throttling while accelerating fluid flow, and the structure of the walls 210 provides a target surface for high-speed fluid flow, enhancing heat exchange effect. Each column can act as both a door and a wall, so all columns have the effect of a door-wall. Optionally, the top of the door-wall structure 205 can be directly connected to the bottom surface of the impingement plate 201 with a small gap.

[0064] According to the embodiment of the present application, the cooling outer ring base structure provides, in operation, that the cold air flows through the impingement holes 204 on the impingement plate 201 into the front chamber of the impingement throttle cavity 202, then part of the cold air flows out through the leading edge holes 206, and part of the cold air axially impacts the door-wall structure 205 and flows into the next chamber of the impingement throttle cavity 202 through the gap between the doors 209 of the door-wall structure 205 and impacts the surface of the wall 210, and then continues to flow into the next chamber from the gaps on both sides of the wall 210, and then continues to flow axially backward, while part of the air flow flows out through the air film holes 207 in each chamber along the air film holes 207 of the perforated plate 203, and the cold air in the last chamber flows out through the trailing edge holes 208 of the perforated plate 203.

[0065] According to the embodiment of the present application, the door wall structure 205 can increase the heat exchange area, and can improve the lateral impact and control the axial pressure along the way. The lateral impact flow is formed through the gap between each row of doors 209, and impacts on the wall 210 at high speed to form a high cooling area, and to enhance the heat exchange in the separate cavity of the impact throttle cavity 202. Meanwhile, the door wall structure 205 controls the throttle to ensure the reasonable control of the inlet pressure of the film hole 207 at the same axial position, and the effect is better than that of the inlet hole throttle. Another advantage of the heat exchange along the way is to realize the axial increase of the temperature in the impact throttle cavity 202, which forms the energy and quality matching with the axial temperature decrease of the main flow (the main flow gas entering the turbine), that is, the high-quality cold gas is used to cool the high-temperature area, and the low-quality cold gas is used to cool the low-temperature area, so as to realize the reasonable use of the cold gas.

[0066] According to the embodiment of the present application, the film holes 207 in the outer ring basic element structure are distributed along the axial direction according to the optimal blowing ratio and reasonable counterflow margin. The advantages are that, in combination with the door wall structure 205 of the impact throttle cavity 202, the total flow area of the film holes 207 between each door wall is adjusted to ensure that the blowing ratio of the film holes 207 is near the optimal blowing ratio; at the same time, the excessively high counterflow margin is reduced to meet the safety; and at the rear edge part, due to the increase of the inlet temperature, the film flow area is increased, the film cooling effect is improved, and the difficulty of flow control at the rear edge is reduced.

[0067] According to the embodiment of the present application, the impact throttle cavity 202 in the outer ring basic element structure is distributed along the axial direction. For the door wall structure 205 in the impact throttle cavity 202, the main target is to cope with the large pressure gradient and temperature gradient (the pressure and temperature distribution is shown in Figures 3-4 ) of the main flow boundary along the axial direction. The hot gas flow of the main flow flows along the axial direction from the leading edge on the left in the figure to the trailing edge on the right, and the leading edge refers to the direction of the main flow incoming flow, and the trailing edge refers to the direction of the main flow outgoing flow. Therefore, first, the position of the large pressure gradient and temperature gradient of the main flow boundary along the axial direction is determined. For the turbine outer ring, the change of the temperature and pressure of the main flow position is mainly caused by the work of the turbine working blade, so the positions of the large temperature and pressure gradients are basically the same, as shown in Figure 3 、 Figure 4The middle part of the two dashed lines represents the position of the leading edge to the trailing edge of the turbine working blade. Since there is a slight relative movement between the turbine components including the blade-bearing rotating disc and the turbine outer ring in the axial direction during the operation of the engine, the door wall structure 205 should cover a range of at least the length of the movement of the tip of the working blade in the axial direction. That is, the range can include the translation of the blade in the axial direction by 2mm to 2mm, i.e. the range of the forward translation of the working blade in the axial direction by 2mm and the backward translation by 2mm. The above-mentioned main flow is the gas flow through the turbine component, and the main flow boundary refers to the part of the gas flow adjacent to the outer ring (the main flow boundary capable of affecting the heat exchange of the hot side wall surface of the outer ring).

[0068] In the high-efficiency cooling outer ring basic element structure provided by the embodiment of the present application, the leading edge cooling is realized by the large impact in the cavity and the leading edge hole 206. The impact holes 204 on the impact hole plate 201 are forwardly inclined to form an impact angle to the leading edge. In order to facilitate processing, the impact hole plate 201 can be bent in a bevel shape at the position of the impact hole 204. The impact hole 204 can be a rim hole, and the number and size of the hole are determined according to the cooling gas flow limitation and the processing hole size limitation. The flow area of the impact hole 201 determines the flow area, and the processing capacity determines the hole size and the number of holes determined by the flow area. The processing method of the impact hole 201 can be electric spark, laser drilling, etc. According to the needs, the processing of the impact hole plate 201 and the film hole plate 203 can be formed by integral casting, or by separate casting and welding after processing. The structure is shown in Figures 9a-9b Figures 9a-9b According to the above-mentioned basic element structure, the array is formed, and under the installation constraint, the turbine outer ring formed is used to constitute the main flow channel around the turbine blade in the engine. The array installation method of the basic element structure according to the embodiment of the present application can refer to the prior art outer ring structure shown in Figure 7

[0069] ​​According to the embodiments of the present invention, the spacing of the gate structures 205 on the film cooling orifice plate 203 in the outer ring basic structure should be as small as possible for the impact throttling chambers 202 between the gate structures 205, in order to maximize the adaptation to the mainstream pressure and temperature gradient, under the condition of no processing restrictions. In practical applications, due to processing limitations, the diameter of the film cooling orifice 207 should not be too small, and the distance between the film cooling orifice 207 and the gate structure 205 needs to be ensured to prevent the influence on the film cooling orifice 207. Therefore, the spacing of the gate structure 205 needs to match the arrangement and size of the film cooling orifice 207. In order to achieve a better cooling effect that can be machined, the spacing of the gate structure 205 can be set to not less than 3mm, so that the opening of the film cooling orifice on it can be easily realized during the machining of the turbine outer ring. As needed, in order to achieve better results, the orifice size of the film cooling orifice 207 can be set between 0.3mm and 0.6mm, and its number is related to the flow distribution. The arrangement scheme adopts an easily machinable, vertically uniformly distributed film cooling orifice to reduce the processing difficulty. Where processing technology and conditions permit, the aperture of the film gas pore 207 can be smaller, and it can be formed at a certain angle in the film gas pore plate 203, so as to better adapt to the mainstream flow and increase the heat exchange area.

[0070] According to one embodiment of the present invention, an impact-throttling-film cooling structure is provided as shown in FIG9. The original single cavity of the impact chamber is divided into multiple sub-cavities by a gate-wall structure 205, each with a film gas flowing out of the main flow. The purpose is to form axially pressure-controllable sub-cavities through the gate-wall structure 205, re-match the inlet and outlet pressure ratio of the axial film gas orifice 207, provide controllable cavity pressure and cold air flow to the film gas orifice 207, and improve the cooling control capability of the main flow side.

[0071] The working process of this structure is as follows: First, all the cooling air enters the impact throttling chamber 202 through the impact hole 204. Since the cooling air all enters from the left side near the leading edge ( Figure 9a When the air enters from the left side (middle), its impact effect will be maximized, and in this case, the demand for cold air at the leading edge will be greatly reduced. Secondly, this structure uses the door-wall structure 205 to direct the impact throttling chamber along... Figure 9aThe axial direction is divided into multiple compartments, and the fluid flowing through each door wall structure converts part of the pressure into impact cooling of the door wall structure of the next compartment. At the same time, the inlet pressure requirement of the gas film hole 207 of the next compartment is met, and the in-line pressure is matched with the main flow pressure. Thirdly, on the basis of controlling the in-line pressure through the door wall structure, the cold gas flow through each gas film hole 207, leading edge hole 206 and trailing edge hole 208 is controlled by adjusting the aperture of the gas film hole. Here, the control of the cold gas flow needs to be combined with the position of the gas film hole outlet, the actual temperature distribution of the wall surface and the indexing limit to achieve optimal adjustment. Finally, under the above treatment, the gas film hole 207 forms a uniform gas film covering the main flow side wall surface, and realizes the precise control of the wall surface.

[0072] According to the embodiment of the present application, the in-line temperature (temperature from the leading edge to the trailing edge in the axial direction) gradually rises in the impact throttling cavity, which can correspond to the gradual decrease of the main flow side temperature, that is, high-quality cold gas is used for cooling the position with high cooling demand, and low-quality cold gas is used for cooling the position with low cooling demand, realizing the step-by-step utilization of in-line capacity and reducing the loss of cold gas. The flow characteristics of the hole are the relationship between the conversion flow and the pressure ratio. When the pressure ratio is the same, the conversion flow can be considered to be the same, that is, when the conversion flow is the same, if the inlet temperature is higher, the flow area required to ensure the same conversion flow is larger. Therefore, the in-line temperature rise can ensure that the trailing edge gas film hole area is relatively larger than the compartment gas supply structure, so that more gas film holes are arranged and better gas film coverage effect is obtained when the gas film hole diameter is fixed.

[0073] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working process of the system, device and unit described above can refer to the corresponding process in the foregoing method embodiment, which will not be repeated here.

[0074] It should be understood that the foregoing describes only some embodiments and changes, modifications, additions and / or variations can be made without departing from the scope and spirit of the disclosed embodiments, which are illustrative rather than restrictive. In addition, the described embodiments relate to currently considered most practical and most preferred embodiments, which should be understood as embodiments should not be limited to the disclosed embodiments, but rather, are intended to cover different modifications and equivalent arrangements included in the spirit and scope of the embodiments. In addition, the above-described various embodiments can be applied together with other embodiments, for example, aspects of one embodiment can be combined with aspects of another embodiment to achieve another embodiment. In addition, each independent feature or component of any given component can constitute another embodiment.

[0075] The above embodiments are only used to illustrate the technical solutions of the present application, and are not intended to limit the present application; although the present application has been described in detail with reference to the above embodiments, those skilled in the art should understand that the technical solutions recorded in the above embodiments can still be modified, or some or all of the technical features can be replaced by equivalents; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application, and they should be covered in the scope of the claims and the description of the present application.

Claims

1. A high-efficiency cooling outer ring cell structure adapted to main flow pressure and temperature changes, characterized by, A plurality of the high-efficiency cooling outer ring basic element structures are arranged in an array to form a turbine outer ring, which constitutes a main flow passage around turbine blades in an engine, and the high-efficiency cooling outer ring basic element structure that adapts to the pressure and temperature changes of the main flow includes: a shock hole plate including a shock hole formed through the shock hole plate at a leading edge portion; a film hole plate including a door wall structure formed in an axial direction on an upper surface thereof, a leading edge hole formed at a leading edge portion of the film hole plate, a film hole formed at a middle portion of the film hole plate, and a trailing edge hole formed at a trailing edge portion of the film hole plate, the film hole being located between the door wall structures; a shock throttling cavity formed by a space between the shock hole plate and the film hole plate after the shock hole plate and the film hole plate are combined, the space of the shock throttling cavity being divided in the axial direction by the door wall structures to form a plurality of sub-cavities having controllable pressure in the axial direction, each of the sub-cavities having a film flow out of the main flow to re-match an inlet-to-outlet pressure ratio of the axial film hole, and to provide controllable cavity pressure and cold gas flow for the film hole; wherein doors are formed in pairs on the upper surface of the film hole plate at positions on both sides in a transverse direction of the film hole plate, and a gap for allowing airflow to pass through is formed between the doors; a wall formed on the upper surface of the film hole plate at a middle position in the transverse direction of the film hole plate, and gaps for allowing airflow to pass through are left on both sides in the transverse direction thereof; wherein the doors and the wall are distributed in the axial direction on the film hole plate with intervals; the leading edge hole is formed horizontally forward at the leading edge portion of the film hole plate; the trailing edge hole is formed horizontally backward at the trailing edge portion of the film hole plate.

2. The high-efficiency cooling outer ring basic element structure that adapts to the pressure and temperature changes of the main flow according to claim 1, wherein: the door wall structure is arranged to cover a width of the turbine blade in the axial direction and an extension of 2 mm forward and backward of the turbine blade in the axial direction.

3. The high-efficiency cooling outer ring basic element structure that adapts to the pressure and temperature changes of the main flow according to claim 1, wherein: the shock hole plate and the film hole plate are integrally cast or are separately cast and then welded together.

4. The high-efficiency cooling outer ring basic element structure that adapts to the pressure and temperature changes of the main flow according to claim 1, wherein: the shock hole plate has a bend at the leading edge portion, and a forwardly inclined shock hole is formed through the shock hole plate at the bend.

5. The high-efficiency cooling outer ring basic element structure that adapts to the pressure and temperature changes of the main flow according to claim 1, wherein: the film hole is formed to penetrate the film hole plate at an inclined angle.

6. The high-efficiency cooling outer ring basic element structure that adapts to the pressure and temperature changes of the main flow according to claim 1, wherein: the film hole is formed to penetrate the film hole plate vertically.

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