CN116398253A - Turbine blade trailing edge cooling structure and turbine blade - Google Patents
Turbine blade trailing edge cooling structure and turbine blade Download PDFInfo
- Publication number
- CN116398253A CN116398253A CN202310203129.1A CN202310203129A CN116398253A CN 116398253 A CN116398253 A CN 116398253A CN 202310203129 A CN202310203129 A CN 202310203129A CN 116398253 A CN116398253 A CN 116398253A
- Authority
- CN
- China
- Prior art keywords
- trailing edge
- radiation
- channel
- turbine blade
- vortex
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 238000001816 cooling Methods 0.000 title claims abstract description 76
- 230000005855 radiation Effects 0.000 claims abstract description 129
- 230000007423 decrease Effects 0.000 claims description 2
- 230000000149 penetrating effect Effects 0.000 claims description 2
- 230000000694 effects Effects 0.000 abstract description 27
- 238000005728 strengthening Methods 0.000 abstract description 13
- 230000001965 increasing effect Effects 0.000 description 15
- 239000012530 fluid Substances 0.000 description 13
- 238000000034 method Methods 0.000 description 9
- 230000004907 flux Effects 0.000 description 7
- 230000006872 improvement Effects 0.000 description 7
- 230000008859 change Effects 0.000 description 6
- 238000002156 mixing Methods 0.000 description 6
- 230000008569 process Effects 0.000 description 6
- 230000002708 enhancing effect Effects 0.000 description 5
- 238000011156 evaluation Methods 0.000 description 5
- 238000011161 development Methods 0.000 description 4
- 238000000926 separation method Methods 0.000 description 4
- 230000000903 blocking effect Effects 0.000 description 3
- 239000002826 coolant Substances 0.000 description 3
- 238000013461 design Methods 0.000 description 3
- 238000005516 engineering process Methods 0.000 description 3
- 230000008646 thermal stress Effects 0.000 description 3
- 230000003993 interaction Effects 0.000 description 2
- 238000004088 simulation Methods 0.000 description 2
- 238000012546 transfer Methods 0.000 description 2
- 230000001133 acceleration Effects 0.000 description 1
- 239000011157 advanced composite material Substances 0.000 description 1
- 230000002411 adverse Effects 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 230000007123 defense Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 231100000989 no adverse effect Toxicity 0.000 description 1
- 230000002093 peripheral effect Effects 0.000 description 1
- 238000010248 power generation Methods 0.000 description 1
- 230000000191 radiation effect Effects 0.000 description 1
- 238000010992 reflux Methods 0.000 description 1
- 230000001105 regulatory effect Effects 0.000 description 1
- 238000004381 surface treatment Methods 0.000 description 1
- 230000007704 transition Effects 0.000 description 1
Images
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01D—NON-POSITIVE DISPLACEMENT MACHINES OR ENGINES, e.g. STEAM TURBINES
- F01D5/00—Blades; Blade-carrying members; Heating, heat-insulating, cooling or antivibration means on the blades or the members
- F01D5/12—Blades
- F01D5/14—Form or construction
- F01D5/18—Hollow blades, i.e. blades with cooling or heating channels or cavities; Heating, heat-insulating or cooling means on blades
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01D—NON-POSITIVE DISPLACEMENT MACHINES OR ENGINES, e.g. STEAM TURBINES
- F01D5/00—Blades; Blade-carrying members; Heating, heat-insulating, cooling or antivibration means on the blades or the members
- F01D5/12—Blades
- F01D5/14—Form or construction
- F01D5/18—Hollow blades, i.e. blades with cooling or heating channels or cavities; Heating, heat-insulating or cooling means on blades
- F01D5/187—Convection cooling
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
- Y02T50/00—Aeronautics or air transport
- Y02T50/60—Efficient propulsion technologies, e.g. for aircraft
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Turbine Rotor Nozzle Sealing (AREA)
Abstract
The invention belongs to the field of turbine blade cooling, and particularly discloses a turbine blade trailing edge cooling structure and a turbine blade, wherein the turbine blade trailing edge cooling structure comprises a turbulent radiation assembly, the turbulent radiation assembly comprises a turbulent radiation plate and a turbulent column, and the turbulent radiation assembly comprises the following components: the turbulence radiation plate is used for separating the front edge surface and the rear edge surface of the tail edge channel of the blade so that the tail edge channel is divided into two layers; the turbulent flow column penetrates through the turbulent flow radiation plate, and two end faces of the turbulent flow column are respectively connected with the front edge face and the rear edge face of the blade tail edge channel correspondingly. The turbulent flow radiation component can strengthen the disturbance of a flow field in a channel and provide an expanded cold surface, and simultaneously strengthen the convection heat exchange and the radiation heat exchange, thereby obviously strengthening the overall cooling performance of the blade trailing edge channel, effectively improving the problem that a huge gap exists between the cooling performance of the local area of the channel, and simultaneously having the heat exchange self-strengthening effect.
Description
Technical Field
The invention belongs to the field of turbine blade cooling, and particularly relates to a turbine blade trailing edge cooling structure and a turbine blade.
Background
The turbine is used as a main component of a gas turbine and an aeroengine, is widely applied to various fields of aviation, ships, power generation and the like, and has great significance to industry and national defense. As the improvement of the front inlet temperature of the turbine can realize the improvement of the overall performance of the gas turbine and the aeroengine, the front inlet temperature of the turbine can reach 2000K at present, and the high temperature resistance limit of the advanced composite material is broken through. In order to ensure the service life of the components and the operation safety, the development of an efficient cooling technology is significant in further strengthening the cooling performance of the turbine blade.
The turbine blade structure may generally be divided into three sections, a leading edge region, a mid-chord region, and a trailing edge region by location. To accommodate the variation in blade structural shape, the blade cooling techniques applied in different areas vary. The front edge of the blade is mostly cooled by adopting means such as impact cooling, air film cooling and the like; the middle chord area adopts the mode of arranging turbulence ribs, pits and the like in the inner cooling channel to improve the heat exchange performance; the tail edge area is mostly in the form of a turbulent flow column, so that the heat exchange is enhanced and the structure is supported.
To ensure aerodynamic performance, the thickness of the turbine blade is gradually reduced in the direction of the trailing edge. Thus, for the trailing edge region, the internal cooling channel is shaped as a converging flow path with the trailing edge, resulting in a narrower internal space relative to the central region. The technique of arranging a spoiler column in a cold channel in the trailing edge region has been widely used, but the spoiler capability for the core region of the channel is weak.
In addition, the existing turbine blade cooling technology mainly relies on enhanced convection to improve heat exchange performance, and the surface radiation effect is not utilized effectively. Because turbine blades are subjected to extremely high thermal loads for a long period of time, particularly near the trailing edge region of the suction side, radiation has a non-negligible effect on the heat exchange process because fluid may transition near the throat of the suction side, often in the presence of a high temperature region. Meanwhile, the temperature of the cooling working medium in the channel rises along the flow direction in the heat exchange process with the structure, and the local cooling effect is poor due to the structural form, so that obvious differences exist between different bit replacement heat, the temperature distribution is uneven, and larger thermal stress is generated. Therefore, it is important how to effectively improve the cooling performance of the blade trailing edge channel, improve the heat exchange uniformity and the temperature uniformity, and reduce the thermal stress caused by the temperature gradient.
Disclosure of Invention
In order to meet the above defects or improvement demands of the prior art, the invention provides a turbine blade trailing edge cooling structure and a turbine blade, and aims to realize the integral improvement of the cooling performance of a blade trailing edge channel, and meanwhile, the problem of great gap exists in effectively improving the cooling performance of a local area of the channel.
To achieve the above object, according to an aspect of the present invention, there is provided a turbine blade trailing edge cooling structure including a spoiler radiation assembly including a spoiler radiation plate and a spoiler column, wherein:
the turbulence radiation plate is used for separating the front edge surface and the rear edge surface of the tail edge channel of the blade so that the tail edge channel is divided into two layers; the vortex column is used for penetrating through the vortex radiation plate, two end faces of the vortex column are respectively connected with the front edge face and the rear edge face of the blade tail edge channel correspondingly, a central angle area is formed at the junction of the vortex column and the vortex radiation plate, and end wall angle areas are respectively formed at the junctions of the vortex column and the front edge face and the rear edge face.
As a further preferable mode, a plurality of turbulent flow columns are arranged, and the diameter d of each turbulent flow column and the width W of the tail edge channel meet that d is more than or equal to 0.06W and less than or equal to 0.09W.
Further preferably, the flow direction spacing S between two adjacent turbulence columns x The diameter d is 1.5d is less than or equal to S x Less than or equal to 3.5d; span-wise spacing S between two adjacent turbulence columns y The diameter d is less than or equal to 1.5d and less than or equal to S y ≤3.5d。
As a further preference, the diameter of the spoiler column gradually decreases in the flow direction.
As a further preferred aspect, the thickness of the spoiler is 2% -8% of the diameter of the spoiler post.
As a further preference, the spoiler tapers in thickness in the flow direction.
As a further preferred feature, the spoiler is a corrugated plate or a flat plate with a concave surface.
As a further preferred aspect, the cross-sectional shape of the spoiler column is circular or streamlined.
As a further preference, both the cooling structure and the trailing edge passage are surface treated to increase their emissivity.
As a further preference, the spoiler is centered or offset in the turbine blade trailing edge channel.
According to another aspect of the present invention, a turbine blade is provided having the above-described turbine blade trailing edge cooling structure mounted within the trailing edge channel of the turbine blade.
In general, compared with the prior art, the above technical solution conceived by the present invention mainly has the following technical advantages:
1. the invention designs a turbulent flow radiation assembly comprising a turbulent flow radiation plate and a turbulent flow column, and the turbulent flow radiation assembly is arranged in a tail edge channel, so that the enhancement of convection heat exchange and radiation heat exchange can be realized at the same time, the integral cooling performance of the tail edge channel of a turbine blade is improved, and meanwhile, the problem that a huge gap exists in the cooling performance of a local area of the channel is effectively improved; in addition, the self-strengthening effect of heat exchange is provided, and when the heated load is increased, the strengthening effect of the cooling performance is improved.
2. The front edge surface and the rear edge surface of the channel are separated by the spoiler so that the channel is divided into two layers, and corner areas appear in the two layers of channels at the joint positions of the front edge of the spoiler column and the wall surface. Therefore, the vortex radiation component not only forms horseshoe vortex at the corner area where the root of the front edge of the vortex column is connected with the front edge surface and the rear edge surface of the channel, but also adds horseshoe vortex at the corner area where the vortex column is connected with the surface of the vortex radiation plate arranged on the vortex column, so that the separation vortex at the back edge reflux area of the vortex column is stronger, and the fluid disturbance at the place is enhanced; the secondary flow is newly added in the core area through the matching of the turbulent flow radiating plate and the turbulent flow column, so that the mixing between the fluids in the tail edge channel is improved, and the heat convection of the core area is enhanced.
3. The turbulent flow radiation component provides an extended cold surface, so that the surface area participating in radiation heat exchange is greatly increased, the radiation heat exchange effect can be enhanced, and the overall cooling performance of the tail edge channel is enhanced.
4. The heat conduction effect inside the radiation spoiler is introduced in the heat exchange process, so that the temperature distribution in the tail edge channel is more uniform, and the overall cooling performance is enhanced.
5. The invention designs parameters such as diameter, interval and the like of the turbulent flow column to improve the disturbance degree of cooling working medium in the channel, enhance the mixing between fluids and simultaneously increase the channel blockage without excessively highRatio. Specifically, as the turbulence column has a disturbance effect on the flow field in the channel, if the diameter of the turbulence column is too small, the arrangement interval is too large, so that the turbulence degree can be weakened; however, because the tail edge channel is contracted along the flow direction, the tail outlet is obviously smaller than the channel inlet, so that the diameter of the turbulent flow column is not too large, the arrangement is not too dense, and otherwise, the flow in the channel is seriously blocked; meanwhile, the blocking effect of the turbulent flow column with the same size on the flow area of the contracted channel is increased along the flow direction, therefore, the diameter d of the turbulent flow column is designed to be 0.06 W.ltoreq.d.ltoreq.0.09W with the width W of the channel, and the diameter of the turbulent flow column is gradually reduced along the flow direction; turbulent flow column flow direction spacing S x The diameter d is less than or equal to 1.5d and less than or equal to S x The span-wise distance S of the turbulent flow column is less than or equal to 3.5d y The diameter d is less than or equal to 1.5d and less than or equal to S y ≤3.5d。
6. The thickness of the vortex radiation plate is 2-8% of the diameter of the vortex column, interaction between the vortex radiation plate and the vortex column is mainly considered, so that the thickness of the vortex radiation plate cannot be too large in order to make the horseshoe vortex/separation vortex stronger, otherwise, effective working space in two layers of a channel is reduced, and development of a vortex structure is affected; the excessive thickness correspondingly causes the mass of the spoiler to increase and causes the flow resistance to be excessive; meanwhile, the turbulent radiation plate thickness is too small, and deformation and damage can occur in the working process of the blade. In addition, because the diameter of the turbulent flow column is gradually reduced along the flow direction, the thickness of the turbulent flow radiation plate can be thinned along the flow direction, so that the turbulent flow radiation plate is further suitable for the contracted flow passage, and the flow resistance is reduced.
7. The turbulent flow radiation plate can be further designed into a corrugated plate, or the surface of the flat plate is provided with the concave, so that the turbulent flow radiation assembly induces more secondary flows while forming horseshoe vortex, the disturbance degree of cooling working media in a channel is improved, and the mixing between fluids is enhanced. Thereby further enhancing the heat exchange effect of the spoiler radiation assembly.
Drawings
FIG. 1 is a schematic view of a turbine blade trailing edge cooling structure in accordance with an embodiment of the present invention;
FIG. 2 is a schematic diagram of arrangement and parameters of spoiler columns in a spoiler radiation assembly according to an embodiment of the present invention;
FIG. 3 is a schematic view showing the change of vortex structure in the trailing edge channel by using only the vortex column and the vortex radiation assembly according to the present invention, wherein (a) is by using only the vortex column and (b) is by using the vortex radiation assembly according to the present invention;
FIG. 4 is a schematic view of heat exchange within a trailing edge channel with a spoiler radiation assembly according to an embodiment of the invention;
FIG. 5 is a schematic view of different shapes and surface structures of a spoiler assembly according to an embodiment of the present invention, wherein (a) is a flat spoiler and (b) is a wave plate spoiler; (c) Wherein (1) is a surface smooth type turbulent flow radiation plate and (2) is a surface with concave type turbulent flow radiation plate; (d) The cross section of the middle (1) is a circular turbulent flow column, and the cross section of the middle (2) is a streamline turbulent flow column;
FIG. 6 is a graph showing the heat exchange effect of the front and rear edge surfaces of the trailing edge channel (model NN) without considering the surface radiation and using only the spoiler column, the trailing edge channel (model NY) with considering the surface radiation and using only the spoiler column, and the trailing edge channel (model YY) with considering the surface radiation and using the spoiler radiation assembly according to the present invention, when Re=10000;
FIG. 7 is a graph showing the heat exchange effect of the front and rear edge surfaces of the trailing edge channel (model NN) without considering the surface radiation and using only the spoiler column, the trailing edge channel (model NY) with considering the surface radiation and using only the spoiler column, and the trailing edge channel (model YY) with considering the surface radiation and using the spoiler radiation assembly according to the present invention, when Re=30000;
FIG. 8 shows the heat flux density q=10000-30000W/m at the surface of the trailing edge channel structure according to the embodiment of the invention 2 When the heat flux density q is changed, the change of the integral heat exchange performance of a tail edge channel (model YY) of the turbulent radiation component is considered, wherein (a) is the integral Nusselt number ratio of the channel
Along with the change of the heat flux q, (b) is the change of the channel heat exchange performance comprehensive evaluation index eta along with the change of the heat flux q;
FIG. 9 shows Re as 10000, q=10000W/m 2 When the invention is adopted, the radiation spoiler assembly (model YY) of the invention is adopted, and the spoiler radiation plateThe thickness of the cooling performance in the tail edge channel is respectively 2%, 4% and 8% of the diameter of the turbulent flow column, wherein (a) is the ratio of the Nusselt number of the whole channel to that of the cooling performance in the tail edge channel
And (b) the comprehensive evaluation index eta of the channel heat exchange performance changes along with the thickness of the turbulent radiation plate.
The same reference numbers are used throughout the drawings to reference like elements or structures, wherein: the cooling device comprises a 1-trailing edge channel, a 2-turbulent flow column, a 3-turbulent flow radiation plate, a 4-leading edge surface, a 5-trailing edge surface and a 6-cooling working medium.
Detailed Description
The present invention will be described in further detail with reference to the drawings and examples, in order to make the objects, technical solutions and advantages of the present invention more apparent. It should be understood that the specific embodiments described herein are for purposes of illustration only and are not intended to limit the scope of the invention. In addition, the technical features of the embodiments of the present invention described below may be combined with each other as long as they do not collide with each other.
According to the turbine blade trailing edge cooling structure provided by the embodiment of the invention, as shown in fig. 1, a trailing edge channel 1 of a turbine blade gradually contracts along the flow direction of a cooling working medium 6, the cooling structure comprises a turbulent radiation assembly, the turbulent radiation assembly is arranged in the trailing edge channel 1, and the turbulent radiation assembly comprises a turbulent radiation plate 3 and a turbulent column 2, wherein:
the spoiler 3 completely separates a leading edge surface 4 and a trailing edge surface 5 of the trailing edge channel; the spoiler column 2 passes through the spoiler radiation plate 3, and two end surfaces of the spoiler column 2 are respectively connected with the front edge surface 4 and the rear edge surface 5 of the tail edge channel 1 correspondingly.
The heat exchange in the tail edge channel can be influenced by adopting the turbulent radiation component in various heat transfer modes, and the principle and the effect are as follows:
(1) The turbulent radiation component can enhance the disturbance of fluid in the tail edge channel and strengthen the convection heat exchange.
When the cooling working medium flows through the tail edge channel, the fluid is blocked by the turbulent flow column, and horseshoe vortices are formed at corner areas where the root parts of the front edges of the turbulent flow column are respectively connected with the front edge surface and the rear edge surface of the tail edge channel; and a reflow region is formed at the rear edge of the spoiler column as shown in fig. 3 (a). However, when a conventional spoiler column is disposed only in the trailing edge channel, its spoiler capability is weak in the channel core region (refer to the inner flow region opposite the near wall region).
After the turbulent flow radiation component is adopted, the front edge surface and the rear edge surface are separated by the turbulent flow radiation plate in the component, so that the channel is divided into two layers, and corner areas are formed in the two layers of channels at the positions where the front edge of the turbulent flow column is connected with the wall surface. Therefore, the vortex radiation component not only forms horseshoe vortex at the corner area where the root of the front edge of the vortex column is connected with the front edge surface and the rear edge surface of the channel, but also adds horseshoe vortex at the corner area where the vortex column is connected with the surface of the vortex radiation plate arranged on the vortex column, and makes the separation vortex at the back edge of the vortex column stronger, thus enhancing the fluid disturbance at the place, as shown in (b) of fig. 3. This means that the secondary flow is newly added in the core region of the channel, increasing the mixing between the fluids in the trailing edge channel, and thus enhancing the convective heat transfer in the core region. Therefore, the enhancement effect on the heat convection of the core area is that more angle areas are formed in the channels so as to form more vortex structures, and the heat convection is realized by the vortex radiation assembly, so that the vortex column and the vortex radiation plate are indispensable.
(2) The turbulent radiation assembly provides an extended cold surface, increasing the surface area involved in radiation heat exchange.
Because the blade is required to bear extremely high heat load during operation, the existing trailing edge channel structure does not have a large-area cold surface with relatively low temperature, and the improvement degree of the overall cooling performance is limited only by the radiation of the high-temperature wall surface of the channel.
According to the invention, the turbulent radiation assembly is arranged between the front edge surface and the rear edge surface in the tail edge channel, and the cooling effect of the cooling medium on the turbulent radiation assembly is utilized to form a cold surface with lower temperature and larger area, so that the radiation heat exchange effect is enhanced, and the overall cooling performance of the tail edge channel is enhanced. As shown in fig. 4, in the trailing edge channel adopting the turbulent radiation assembly, in addition to the external heat flow heating the channel wall surface by means of convection heat exchange, there are heat conduction between the channel wall surface and the turbulent radiation assembly, heat conduction inside the turbulent radiation assembly, convection heat exchange between the channel wall surface and the cooling medium, convection heat exchange between the turbulent radiation assembly surface and the cooling medium, and radiation heat exchange between the turbulent radiation assembly surface and the channel wall surface. Particularly, the spoiler in the spoiler radiation assembly provides a large area of cold surface with lower temperature, and radiation heat exchange between the spoiler radiation assembly and the channel wall surface is greatly enhanced. Therefore, the turbulent radiation assembly strengthens radiation heat exchange by providing a large area of low temperature cold surface, thereby strengthening the overall cooling performance.
(3) The spoiler radiation assembly increases the heat conduction.
The cooling working medium is heated continuously when flowing through the high-temperature wall surface along the flow direction after flowing in from the tail edge channel, and the temperature difference between the cooling working medium and the channel wall surface is reduced, so that the cooling performance along the path is adversely affected.
According to the invention, the turbulent radiation assembly is arranged between the front edge surface and the rear edge surface of the tail edge channel, and the heat conduction effect inside the radiant spoiler is introduced in the heat exchange process, so that the radiant heat exchange between the radiant spoiler and the surface of the high-temperature structure and the convective heat exchange between the radiant spoiler and the cooling working medium are influenced, the temperature distribution in the tail edge channel is more uniform, and the overall cooling performance is enhanced.
Therefore, compared with the existing turbine blade technology, the design of the invention has no adverse effect on structural strength, and can reasonably utilize various heat exchange forms in the blade tail edge channel under the high-temperature working condition. The turbulent flow radiation assembly can simultaneously strengthen the convection heat exchange and the radiation heat exchange. On one hand, the turbulent radiation component can enable more vortex structures to be formed in the tail edge channel, so that disturbance of fluid in a core area is enhanced, blending between the fluids is enhanced, and therefore convection heat exchange is enhanced; on the other hand, the turbulent flow radiation component artificially expands the cold surface, and can greatly increase the surface area participating in radiation heat exchange, thereby strengthening the radiation heat exchange.
Further, as shown in FIG. 2, the diameter d of the spoiler column and the width W of the trailing edge channel satisfy 0.06 W.ltoreq.d.ltoreq.0.09W, and the diameter of the spoiler column can be gradually reduced along the flow direction; flow direction spacing S of turbulent flow column x The diameter d is 1.5d is less than or equal to S x ≤3.5d; span-wise spacing S of spoiler column y The diameter d is 1.5d is less than or equal to S y Less than or equal to 3.5d; and S is x And S is equal to y May not be equal. The turbulence column has a disturbance effect on a flow field in the channel, and if the diameter of the turbulence column is too small, the arrangement interval is too large, so that the turbulence degree can be weakened; however, because the tail edge channel contracts along the flow direction, the tail outlet height is obviously smaller than the channel inlet, so that the diameter of the turbulent flow column is not too large, the arrangement is not too dense, otherwise, the flow in the channel is seriously blocked, and the blocking effect of the turbulent flow column with the same size on the flow area of the contracted channel increases along the flow direction.
Furthermore, compared with a smooth rectangular channel, the vortex radiation plate is arranged in the shrinkage tail edge channel provided with the conventional vortex column, the space is limited, the channel height is changed everywhere, and the implementation is relatively more difficult, and the thickness of the vortex radiation plate is designed to be 2-8% of the diameter d of the vortex column, namely, delta is more than or equal to 0.02d and less than or equal to 0.08d. Mainly considering the interaction of the vortex radiation plates and the vortex columns, in order to make the horseshoe vortex/separation vortex stronger, the thickness of the vortex radiation plates cannot be too large, otherwise, the effective working space in two layers of a channel is reduced, and the development of a vortex structure is affected; meanwhile, the realization of the intensified radiation heat exchange needs to ensure the heat exchange area of the turbulent radiation plate without excessive thickness, otherwise, the mass of the turbulent radiation plate is correspondingly increased, and the flow resistance is excessively large, so that the thickness of a control plate is needed, and the blocking ratio of a channel is prevented from being greatly increased. On the other hand, the thickness of the turbulent radiation plate is too small and can be deformed and damaged in the working process of the blade, so that the thickness of the turbulent radiation plate correspondingly meets the strength requirement.
In addition, the diameter of the turbulent flow column can be gradually reduced along the flow direction, so that the thickness of the turbulent flow radiation plate can be thinned along the flow direction, and the flow resistance is reduced; and the included angle between the spoiler and the spoiler column can be different from 90 degrees so as to further adapt to the contracted flow channel.
Furthermore, the emissivity of the turbulent radiation component and the emissivity of the tail edge channel are improved in a surface treatment mode, so that the turbulent radiation component and the tail edge channel have good surface radiation characteristics, and the overall heat exchange performance of the channel is more balanced.
Further, by improving the form of the spoiler radiation assembly, enhanced cooling performance may be optimized. As shown in fig. 5, the spoiler disposed on the spoiler radiation assembly includes, but is not limited to, a flat plate or a corrugated plate, and may be further matched with a recess disposed on the surface of the spoiler radiation assembly, so that the spoiler radiation assembly induces more secondary flows while forming a horseshoe vortex, the disturbance degree of the cooling working medium in the channel is improved, and the blending between fluids is enhanced, thereby further enhancing the heat exchange effect of the spoiler radiation assembly. The cross section of the turbulent flow column adopts a round shape or streamline shape, so that the heat exchange effect is improved and the flow resistance is reduced.
The following are specific examples:
cylindrical spoiler columns are arranged between the front edge surface and the rear edge surface in an interposed manner, and spoiler radiation plates with smooth surfaces are arranged on the spoiler columns to completely isolate the front edge surface and the rear edge surface. External heat is transmitted through the peripheral wall surfaces of the channels, and cooling working medium is selected from air with the temperature of 723K, and the air flows through the channels through the inlets to cool the structure.
Meanwhile, a Nusselt number ratio is defined as Nu t /Nu 0 The comprehensive evaluation index of the channel heat exchange performance is eta= (Nu) t /Nu 0 )/(f/f 0 ) 1/3 . Wherein Nu 0 And f 0 Nusselt numbers and drag coefficients of smooth channels of the spoiler-less radiation assembly, respectively, are used as comparison references to exclude the influence of the channels on the acceleration of the airflow.
(1) First group of embodiments
In order to facilitate comparison of the enhancement of cooling performance in the trailing edge channels after the radiation spoiler assembly (model YY) of the present invention, numerical simulations were performed for the trailing edge channels (model NN) that did not consider surface radiation and used only spoiler posts, and for the trailing edge channels (model NY) that did consider surface radiation and used only spoiler posts, respectively.
Fig. 6 and 7 show reynolds numbers re=10000 and re=30000, respectively (the heat flux density q of the structural surface is 10000W/m 2 ) The heat exchange performance of the front and rear edge surfaces of the channels under the three conditions of model NN, model NY and model YY are compared by Nu t /Nu 0 And (3) representing. It can be seen that in the trailing edge channelThe turbulent flow radiation component is adopted to provide an extended cold surface, the convection heat exchange is enhanced by enhancing the fluid disturbance in the channel while the radiation heat exchange is enhanced, and the integral cooling performance of the channel is obviously improved under different Reynolds numbers.
When re=10000, the maximum temperature of the tail edge channel adopting the invention is 933.77K, and the average temperature is 814.19K; whereas when surface radiation is not considered and only a turbulent column is used, the maximum temperature is 1288.50K and the average temperature is 852.76K. In contrast, the invention reduces the highest temperature and average temperature by 27.53% and 4.52%, respectively, and the temperature distribution is more uniform.
When re=30000, the maximum temperature of the trailing edge channel with the invention was 874.78K and the average temperature was 770.64K; whereas when surface radiation is not considered and only a turbulent column is used, the maximum temperature is 1010.04K and the average temperature is 783.45K. In contrast, the invention reduces the highest temperature and average temperature by 13.39% and 1.64%, respectively, and the temperature distribution is more uniform.
The embodiment shows that the invention can realize the integral improvement of the cooling performance of the tail edge channel under different Reynolds numbers, can effectively improve the problem that the cooling performance of the local area of the channel has a huge gap, and reduces the thermal stress caused by temperature gradient.
(2) Second group of embodiments
To show that the invention has the self-strengthening effect of heat exchange (i.e. the strengthening effect of the cooling performance is improved when the heated load is increased), the heat flux density q of the structural surface is 10000-30000W/m 2 Under the condition, the numerical simulation of the cooling performance in the trailing edge channel of the radiation turbulence assembly (model YY) is carried out.
FIG. 8 shows Re as 10000, q=10000 to 30000W/m 2 When the method is adopted, the relationship of the strengthening effect of the cooling performance in the tail edge channel (model YY) along with the change of the heat flow density is adopted. It can be seen that the overall Nusselt number ratio of the channels increases with increasing heat flux density
And heat exchange performance comprehensive evaluationThe index eta is increased to show that the invention has the heat exchange self-strengthening effect, and the strengthening effect of the cooling performance is improved when the heated load is higher. For example, when q=30000W/m 2 When the invention is adopted, the highest temperature of the channel is 1196.85K, and the average temperature is 980.04K; whereas when surface radiation is not considered and only a turbulent column is used, the maximum temperature is 2370.26K and the average temperature is 1112.97K. In contrast, the highest and average temperatures were reduced by 49.51% and 11.94%, respectively, with the present invention. The result ratio q=10000W/m at the same Re 2 The enhanced cooling degree is obviously improved, and the heat exchange self-strengthening effect of the invention is further proved.
(3) Third group of embodiments
To verify the effect of the parameters of the spoiler post and the spoiler designed by the invention on the cooling effect, the width W of the trailing edge channel is 160mm, and the diameter d of the spoiler post is 12mm. FIG. 9 shows Re as 10000, q=10000W/m 2 When the radiation spoiler assembly (model YY) is adopted, the cooling performance in the tail edge channel is compared when the thickness of the spoiler is respectively 2%, 4% and 8% of the diameter of the spoiler column. It can be seen that the integral Nusselt number ratio of the channels increases with the thickness of the spoiler
Slightly increased, but the heat exchange performance comprehensive evaluation index eta is slightly reduced. The reason is that when the thickness of the turbulent radiation plate is slightly increased, the actual flow velocity in the channels at the two sides is increased, and the convection heat exchange is slightly enhanced; but the flow resistance in the channel is correspondingly increased, so that the comprehensive evaluation index of the heat exchange performance is slightly reduced.
Therefore, although the flow velocity of the two sides can be properly regulated when the thickness of the turbulence radiation plate is slightly increased within a certain range, the thickness of the turbulence radiation plate cannot be excessively large, otherwise, the effective working space in the separated two side channels is reduced, and the development of a vortex structure is influenced; meanwhile, an excessive thickness may cause an increase in mass of the spoiler and cause an excessive flow resistance. However, too small a thickness may be subject to deformation damage during operation of the blade. The thickness of the spoiler should be as thin as possible while meeting the strength requirements.
It will be readily appreciated by those skilled in the art that the foregoing description is merely a preferred embodiment of the invention and is not intended to limit the invention, but any modifications, equivalents, improvements or alternatives falling within the spirit and principles of the invention are intended to be included within the scope of the invention.
Claims (10)
1. The utility model provides a turbine blade trailing edge cooling structure, its characterized in that includes vortex radiation subassembly, vortex radiation subassembly includes vortex radiation board and vortex post, wherein:
the turbulence radiation plate is used for separating the front edge surface and the rear edge surface of the tail edge channel of the blade so that the tail edge channel is divided into two layers; the vortex column is used for penetrating through the vortex radiation plate, two end faces of the vortex column are respectively connected with the front edge face and the rear edge face of the blade tail edge channel correspondingly, a central angle area is formed at the junction of the vortex column and the vortex radiation plate, and end wall angle areas are respectively formed at the junctions of the vortex column and the front edge face and the rear edge face.
2. The turbine blade trailing edge cooling structure according to claim 1, wherein the number of the turbulence columns is plural, and the diameter d of the turbulence columns and the width W of the trailing edge passage satisfy 0.06 w.ltoreq.d.ltoreq.0.09W.
3. The turbine blade trailing edge cooling structure according to claim 2, wherein a flow direction spacing S between adjacent ones of the turbulators x The diameter d is 1.5d is less than or equal to S x Less than or equal to 3.5d; the span-wise distance S between the two adjacent turbulence columns y The diameter d is 1.5d is less than or equal to S y ≤3.5d。
4. The turbine blade trailing edge cooling structure as claimed in claim 2, wherein the diameter of the turbulator post is gradually reduced in the flow direction.
5. The turbine blade trailing edge cooling structure as claimed in claim 1, wherein the thickness of the spoiler is 2% -8% of the spoiler column diameter.
6. The turbine blade trailing edge cooling structure as claimed in claim 5, wherein the thickness of the spoiler gradually decreases in a flow direction.
7. The turbine blade trailing edge cooling structure according to claim 1, wherein the spoiler is a corrugated plate or a flat plate provided with a recess on a surface thereof; the cross section of the turbulent flow column is round or streamline.
8. The turbine blade trailing edge cooling structure of claim 1 wherein both the cooling structure and the trailing edge passage are surface treated to increase emissivity thereof.
9. The turbine blade trailing edge cooling structure as claimed in any one of claims 1 to 8 wherein the spoiler is centered or offset in the turbine blade trailing edge passage.
10. A turbine blade having a trailing edge cooling structure according to any one of claims 1 to 9 mounted within its trailing edge passage.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310203129.1A CN116398253A (en) | 2023-03-03 | 2023-03-03 | Turbine blade trailing edge cooling structure and turbine blade |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310203129.1A CN116398253A (en) | 2023-03-03 | 2023-03-03 | Turbine blade trailing edge cooling structure and turbine blade |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN116398253A true CN116398253A (en) | 2023-07-07 |
Family
ID=87013166
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202310203129.1A Pending CN116398253A (en) | 2023-03-03 | 2023-03-03 | Turbine blade trailing edge cooling structure and turbine blade |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN116398253A (en) |
-
2023
- 2023-03-03 CN CN202310203129.1A patent/CN116398253A/en active Pending
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| EP1444418B1 (en) | Internal cooled gas turbine vane or blade | |
| CN211715181U (en) | Laminate cooling structure with slotted circular turbulence column | |
| CN112459852B (en) | Be applied to two water conservancy diversion rib water conservancy diversion structures of turbine blade trailing edge half-splitting seam | |
| US20170328280A1 (en) | Heat sink | |
| US20090250191A1 (en) | Foam Metal Heat Exchanger System | |
| CN107060892B (en) | A kind of turbine blade cooling unit of gas-liquid coupling | |
| US20150176412A1 (en) | Rotor blade and guide vane airfoil for a gas turbine engine | |
| WO2023173880A1 (en) | Heat exchanger based on gd type hybrid minimal curved surface disturbance structure | |
| CN113236373B (en) | Tesla valve-based air film hole channel structure and application thereof to turbine blade leading edge | |
| CN115898693A (en) | Corrugated turbulent flow plane cooling device and application | |
| Nourin et al. | Investigation of jet impingement cooling for gas turbine blade with in-line and staggered nozzle arrays | |
| CN112523810B (en) | Triangular column type flow guide structure applied to turbine blade trailing edge half-splitting seam | |
| CN112343667B (en) | Continuous V-shaped rib flow guide structure applied to turbine blade trailing edge half-splitting seam | |
| CN108590776A (en) | A kind of turbine blade cooling method using triangular pyramid vortex generator | |
| CN116398253A (en) | Turbine blade trailing edge cooling structure and turbine blade | |
| CN216642214U (en) | High-blockage-ratio finned laminate cooling structure for middle chord area of turbine blade | |
| CN114382553B (en) | High-blockage-ratio rib laminate cooling structure and cooling method for middle chord zone of turbine blade | |
| CN114109518A (en) | Turbine blade leading edge ribbed rotational flow-air film composite cooling structure | |
| Zhao et al. | The augmentation of internal tip heat transfer in gas turbine blades using a pair of delta-winglet vortex generators | |
| CN115013075A (en) | Anti-slip pattern-shaped turbulence rib and turbine blade | |
| CN107191230A (en) | A kind of blade cooling MCA | |
| Qiu et al. | Effect of truncated pin-fins on flow and heat transfer characteristics with impinging jets on a concave surface | |
| Amano et al. | Advances in gas turbine blade cooling technology | |
| CN113738452B (en) | Internal cooling channel cooling structure for turbine blade | |
| JPS6285102A (en) | Gas turbine cooling blade |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination |