Turbulator Design for Cooling of High Heat Load Internal Channels

Abstract

The present invention relates to a turbulence generator for cooling an internal flow path with a high thermal load and a turbulence generator for cooling a gas turbine blade. More specifically, the invention relates to a turbulence generator for cooling an internal flow path with a high thermal load and a turbulence generator for cooling a gas turbine blade, which can effectively manage heat by applying a lip turbulator to the internal cooling channel of a gas turbine blade to promote turbulence and generate a secondary flow.

Description

Technology Field

[0001] The present invention relates to a turbulence generator for cooling an internal flow path with a high thermal load and a turbulence generator for cooling a gas turbine blade. More specifically, the invention relates to a turbulence generator for cooling an internal flow path with a high thermal load and a turbulence generator for cooling a gas turbine blade, which can effectively manage heat by applying a lip turbulator to the internal cooling channel of a gas turbine blade to promote turbulence and generate a secondary flow. Background Technology

[0002] Recently, increasing the efficiency of gas turbines has become a very important task, and to this end, turbine inlet temperatures have been continuously increasing. Internal cooling technology is crucial for gas turbine blades to withstand high-temperature environments. A representative internal cooling technology involves effectively managing heat using a rib turbulator; however, since rib turbulators have various variables such as width, length, height, arrangement, shape, and pitch, it is important to set optimal parameters. Figures 1a and 1b show the configuration and image of a gas turbine. Figure 2 illustrates a gas turbine blade having a cooling channel.

[0003] Global demand for electricity is increasing, and gas turbines are playing a pivotal role in meeting this energy demand. Growing at an annual rate of 4.5% since 2019, the market is projected to reach $27.9 billion by 2033. Gas turbines are primarily applied in power generation and aviation sectors. When analyzing market share by type, capacity, and technology, large gas turbines are dominant in terms of type, capacity exceeding 300 MW, and combined cycle technology.

[0004] A gas turbine is a device that converts the chemical energy of fuel into thermal energy to generate rotational mechanical energy. As shown in Fig. 1a, it consists of a compressor, a combustor, and a turbine, and the compressor and turbine are composed of multiple stages. Gas turbines are used for propulsion of aircraft and ships, or for power generation to produce electricity.

[0005] To increase the efficiency of gas turbines, turbine inlet temperatures have steadily increased, and accordingly, cooling technologies are being developed to improve thermal fatigue and thermal durability. Cooling technologies include internal cooling utilizing fin-fin structures and rib turbators, external cooling including impingement cooling and film cooling, and thermal shielding coatings.

[0006] Different cooling techniques are applied to the leading edge part, serpentine part, and trailing edge part of the gas turbine for internal cooling. Since the thermal load is strongest in the leading edge part, impingement cooling is applied, and because the flow velocity is high, a lip turbulator is applied to only one side to minimize pressure loss.

[0007] Ripturbators improve heat transfer performance by promoting turbulence, and their variables include shape, pitch, height, and width. While heat transfer is enhanced by these various variables, pressure drop also increases simultaneously; therefore, the selection of optimal variables and numerical settings are crucial.

[0008] Currently, research on changes in the shape and arrangement of ripturbators is actively underway, and research on the optimization of ripturbators using AI is also being conducted, but there is a lack of validation experiments to support this, and there is a lack of research on internal cooling through experiments such as PIV. Prior art literature

[0009] Japanese Published Patent 2014-509712 Korean Published Patent 10-2019-0037492 Japanese Published Patent 2010-203440 The problem to be solved

[0010] Accordingly, the present invention has been devised to solve the aforementioned conventional problems. According to an embodiment of the present invention, the purpose is to propose a structure that improves the cooling efficiency of gas turbine components that must withstand high temperatures by attaching a lip turbulator to the front of the gas turbine blade cooling path.

[0011] According to an embodiment of the present invention, internal cooling of a gas turbine blade is an important technology for improving thermal durability and lifespan in a high-temperature environment, and since the front part, which receives the most heat load, requires simultaneous consideration of pressure drop and heat transfer, a lip turbulator is attached to one side, and the lip turbulator promotes turbulence and generates secondary flow to effectively manage heat. The purpose is to provide a turbulence generator for cooling an internal flow path with a high heat load and a turbulence generator for cooling a gas turbine blade.

[0012] Meanwhile, the technical problems to be solved by the present invention are not limited to those mentioned above, and other technical problems not mentioned will be clearly understood by those skilled in the art to which the present invention belongs from the description below. means of solving the problem

[0013] The first objective of the present invention can be achieved as a turbulence generator for cooling an internal flow path with a strong heat load, characterized by having a plurality of rip turbulators installed at a specific pitch value along the flow direction on one side of the cooling flow path.

[0014] The second objective of the present invention can be achieved as a turbulence generator for cooling gas turbine blades, characterized by having a plurality of rip turbulators installed at a specific pitch value along the flow direction on one side of the front section of the internal cooling channel of the gas turbine.

[0015] For the first and second purposes, the cooling channel may be characterized by the length of the shear section before installation of the ripturbator (Lin), the length of the installation section (Lt), and the length of the section after installation (Lout) being 10~14 : 6~12 : 25~35.

[0016] For the first and second purposes, the lip turbulator may be characterized by including a first lip turbulator that is spaced apart in the flow direction based on the specific pitch value with respect to the flow direction centerline centered in the width direction with respect to the one surface of the cooling channel and has a longitudinal direction in the first lateral direction of the centerline, and a second lip turbulator that is located between each of the first lip turbulators, is spaced apart in the flow direction based on the specific pitch value, and has a longitudinal direction in the second lateral direction of the centerline.

[0017] For the first and second purposes, the above ripturbulator may be characterized by having a width, height, and length, and the width and height being in a ratio of 1:0.8 to 1.2.

[0018] For the first and second purposes, the width and length may be characterized as being 1:15 to 25.

[0019] For the first and second purposes, the specific pitch may be characterized as being 6 to 10 times the width.

[0020] For the first and second purposes, the height may be characterized as being 0.04 to 0.06 relative to the height of the cooling channel. Effects of the invention

[0021] According to an embodiment of the present invention, a structure can be provided that improves the cooling efficiency of gas turbine components that must withstand high temperatures by attaching a lip turbulator to the front of the gas turbine blade cooling path.

[0022] According to the turbulence generator for cooling an internal flow path with a strong heat load and the turbulence generator for cooling a gas turbine blade according to an embodiment of the present invention, internal cooling of a gas turbine blade is an important technology for improving thermal durability and lifespan in a high-temperature environment, and among them, the front part which receives the most heat load must simultaneously consider pressure drop and heat transfer, so a lip turbulator is attached to one side, and the lip turbulator promotes turbulence and generates secondary flow to effectively manage heat.

[0023] Meanwhile, the effects obtainable from the present invention are not limited to those mentioned above, and other unmentioned effects will be clearly understood by those skilled in the art to which the present invention belongs from the description below. Brief explanation of the drawing

[0024] The following drawings attached to this specification illustrate preferred embodiments of the present invention and serve to further enhance understanding of the technical concept of the present invention together with the detailed description of the invention; therefore, the present invention should not be interpreted as being limited only to the matters described in such drawings. Figures 1a and 1b are a schematic diagram and an image of a gas turbine, FIG. 2 shows a gas turbine blade having a cooling channel, FIG. 3 is a side view of a cooling channel and a turbulence generator equipped with a lip turbulator according to an embodiment of the present invention. FIG. 4a is a plan view of a cooling channel according to an embodiment of the present invention, FIG. 4b is a side cross-sectional view of a lip turbulator according to an embodiment of the present invention, FIG. 5 is a graph of pressure drop with respect to the Reynolds number according to an experimental example of the present invention, FIG. 6 is a setting photograph for the first experimental example of the present invention, FIGS. 7 to 15 are result data according to the first experimental example of the present invention, FIGS. 16a and 16b are a configuration diagram and a setting photograph for the second experimental example of the present invention. FIGS. 17 to 21 illustrate result data for the second experimental example of the present invention. Specific details for implementing the invention

[0025] The above objects, other objects, features, and advantages of the present invention will be easily understood through the following preferred embodiments associated with the accompanying drawings. However, the present invention is not limited to the embodiments described herein and may be embodied in other forms. Rather, the embodiments introduced herein are provided to ensure that the disclosed content is thorough and complete and to ensure that the spirit of the invention is sufficiently conveyed to a person skilled in the art.

[0026] In this specification, when a component is described as being on another component, it means that it may be formed directly on the other component or that a third component may be interposed between them. Also, in the drawings, the thicknesses of the components are exaggerated for the effective description of the technical content.

[0027] The embodiments described herein will be explained with reference to cross-sectional and / or plan views, which are exemplary illustrations of the invention. In the drawings, the thicknesses of films and regions are exaggerated for effective explanation of the technical content. Accordingly, the shapes of the exemplary drawings may be modified by manufacturing techniques and / or tolerances, etc. Accordingly, the embodiments of the invention are not limited to the specific shapes depicted but include variations in shape produced according to the manufacturing process. For example, a region depicted as a right angle may be rounded or have a certain curvature. Accordingly, the regions illustrated in the drawings have properties, and the shapes of the regions illustrated in the drawings are intended to illustrate specific shapes of the regions of the device and are not intended to limit the scope of the invention. Although terms such as first, second, etc., have been used to describe various components in the various embodiments of this specification, these components should not be limited by such terms. These terms are used merely to distinguish one component from another. The embodiments described and illustrated herein also include their complementary embodiments.

[0028] The terms used herein are for describing the embodiments and are not intended to limit the invention. In this specification, the singular form includes the plural form unless specifically stated otherwise in the text. As used herein, 'comprises' and / or 'comprising' do not exclude the presence or addition of one or more other components to the mentioned components.

[0029] In describing the specific embodiments below, various specific details have been included to explain the invention more specifically and to aid understanding. However, a reader with sufficient knowledge in the art to understand the invention will recognize that it can be used without these various specific details. In some cases, it is noted in advance that commonly known aspects that are not significantly related to the invention have been omitted to prevent unnecessary confusion in describing the invention.

[0031] Hereinafter, the configuration and function of a turbulence generator for cooling an internal flow path with a high thermal load and a turbulence generator for cooling a gas turbine blade according to an embodiment of the present invention will be described.

[0032] FIG. 3 is a side view of a turbulence generator equipped with a lip turbulator according to an embodiment of the present invention and a cooling channel.

[0033] And FIG. 4a shows a plan view of a cooling channel according to an embodiment of the present invention. Also, FIG. 4b shows a side cross-sectional view of a lip turbulator according to an embodiment of the present invention.

[0034] In FIG. 3, the width and height of the gas turbine blade cooling channel according to an embodiment of the present invention are W and H, and the length of the shear section before the installation of the ripturbator in the cooling channel is Lin, the length of the installation section is Lt, and the length of the section after installation is Lout.

[0035] Figure 4b shows the shape and structure of a lip turbulator attached to the installation section, where P represents the pitch value, e represents the width of the lip, and h represents the height of the lip. Figure 4a is a plan view of the lip turbulator installation section, in which the first lip turbulator and the second lip turbulator have a zigzag arrangement relative to each other.

[0036] According to an embodiment of the present invention, the cooling channel may be characterized by the length of the shear section before installation of the ripturbator (Lin), the length of the installation section (Lt), and the length of the section after installation (Lout) being 10~14 : 6~12 : 25~35.

[0037] In addition, the ripturbulator has a zigzag arrangement of the first ripturbulator and the second ripturbulator.

[0038] That is, as illustrated in FIG. 4a, the plurality of lip turbators is configured to include a plurality of first lip turbators that are spaced apart in the flow direction based on the specific pitch value with respect to the flow direction centerline centered in the width direction with respect to the one surface of the cooling channel and have a longitudinal direction in the first lateral direction of the centerline, and a plurality of second lip turbators that are located between each of these plurality of first lip turbators, spaced apart in the flow direction based on the specific pitch value, and have a longitudinal direction in the second lateral direction of the centerline.

[0039] A lip turbulator according to an embodiment of the present invention has a width (e), a height (h), and a length, and is spaced apart from each other at a specific pitch. The direction of the width (e) and the specific pitch (P) of the lip turbulator is the flow direction, and the length direction of the lip turbulator is the width direction of the cooling channel.

[0040] The width (e) and height (h) of the ripturbulator according to this embodiment of the present invention are 1:0.8 to 1.2.

[0041] And the width (e) and length of the ripturbulator according to an embodiment of the present invention are 1:15 to 25.

[0042] In addition, the specific pitch (P) of the ripturbulator according to an embodiment of the present invention is 6 to 10 times the width (e).

[0043] And the height (h) of the ripturbator according to an embodiment of the present invention is 0.04 to 0.06 relative to the height (W) of the cooling channel.

[0045] Below, we will describe an experimental example and result data regarding a turbulence generator for cooling gas turbine blades to which a ripturbulator according to the embodiment of the present invention mentioned above is applied.

[0046] Figure 5 illustrates a graph of pressure drop with respect to the Reynolds number according to an experimental example of the present invention. Figure 5 shows the pressure drop measured by a pressure sensor as the flow rate increases due to the attachment of a lip turbulator. It can be seen that the pressure drop increases as the Reynolds value increases from 10,000 to 40,000.

[0047] FIG. 6 shows a setting photograph for the first experimental example of the present invention. FIG. 7 to FIG. 17 show result data according to the first experimental example of the present invention.

[0048] Tables 1 and 2 below show the experimental parameters and experimental conditions.

[0049] [Table 1]

[0050]

[0051] [Table 2]

[0052]

[0053] As shown in Fig. 5, images of temperature changes in the flow with respect to the Reynolds number were obtained using a thermal imaging camera. Fig. 7 shows thermal imaging camera images for Re 10000, 20000, 30000, and 40000. It can be seen that the cooling effect increases as the value increases from 10000 to 40000.

[0054] Figure 8 is a thermal image of the flow direction and width direction, and Figures 9a to 9b, 10a to 10b, and the left side of Figure 13 show the Nusselt number according to the flow direction for Re 10000, 20000, 30000, and 40000 at the width direction X / de = 3.75 point.

[0055] Also, FIGS. 11a to 11b, FIGS. 12a to 12b, and the right side of FIG. 13 show the Nusselt numbers according to the flow direction for Re 10000, 20000, 30000, and 40000 at the width direction X / de = 5 point.

[0056] Figure 15 shows the Nusselt numbers according to the width direction for Re 10000, 20000, 30000, and 40000 at the flow direction Z / de = 15.5 point in Figure 14.

[0058] FIGS. 16a and 16b show a configuration diagram and a setting photograph for the second experimental example of the present invention. Table 3 below shows the PIV experimental conditions table.

[0059] [Table 3]

[0060]

[0061] FIGS. 17 to 21 illustrate result data for the second experimental example of the present invention.

[0062] FIG. 16a is a schematic diagram of the second experimental example of the present invention, wherein a flow rate is supplied using a 3-horsepower blower in the flow direction, and particles and water are mixed using an atomizer and placed into a mister, which is then operated to move the particles from left to right. Subsequently, a laser equipped with an optic lens is installed on the upper part of a test section to which a lip turbulator is attached, thereby creating a laser sheet within the test section. Afterward, the passage of particles through the created laser sheet is captured using a high-speed camera, and vector results are obtained through a flownizer program to verify the flow characteristics.

[0063] Figure 17 shows the positions where a laser is applied to the lip turbulator during the PIV experiment. To verify the flow characteristics of the entire zigzag array, the experiment was conducted at the following positions.

[0064] Figures 18 to 21 show the flow around the lip turbulator for Re 10000, 20000, 30000, and 40000, respectively, represented as vector values ​​through an analysis program.

[0065] When heat flow conditions are applied, it can be observed that the temperature between the lips increases and then decreases, and that recirculation occurs before and after the lip turbulator and the fluid reattaches to the wall. The results of the flow visualization experiment show that the fluid flow remains similar even when the flow increases.

[0067] In addition, the apparatus and method described above are not limited to the configurations and methods of the embodiments described above; rather, all or part of each embodiment may be selectively combined to allow for various modifications to be made.

Claims

Claim 1 As a turbulence generator for cooling an internal flow path with a high thermal load, the cooling flow path equipped with the turbulence generator has a shear section length (L) prior to the installation of the turbulator. in ), length of the installation section where the ripturbator is installed (L t ), and length of the rear section after the installation of the ripturbulator (L out The ratio of ) is limited to 10~14 : 6~12 : 25~35, and the length of the installation section (L) t A plurality of rip turbulators are installed spaced apart from each other along the flow direction on one surface of a cooling channel, wherein each of the plurality of rip turbulators has a width (e), a height (h), and a length (l) and is formed to protrude from one surface of the cooling channel, and has an asymmetric zigzag arrangement structure including a plurality of first rip turbulators spaced apart along the flow direction and having a longitudinal direction in the first lateral direction of the center line, based on a flow direction center line which is the width direction center of the cooling channel, and a plurality of second rip turbulators located between each of the plurality of first rip turbulators, spaced apart along the flow direction, and having a longitudinal direction in the second lateral direction of the center line, wherein the pitch (P), which is the flow direction spacing distance between the first rip turbulators and between the second rip turbulators, is limited to a range of 6 to 10 times the width (e), the height (h) is in the range of 0.8 to 1.2 times the width (e), and the length (l) is A turbulence generator for cooling an internal flow path with a high thermal load, characterized by being structured in a range of 15 to 25 times the width (e). Claim 2 delete Claim 3 delete Claim 4 delete Claim 5 delete Claim 6 delete Claim 7 A turbulence generator for cooling an internal passage with a strong heat load, characterized in that, in claim 1, the height is 0.04 to 0.06 relative to the height of the cooling passage. Claim 8 As a turbulence generator for cooling gas turbine blades, the internal cooling channel of the gas turbine equipped with the turbulence generator has a shear section length (L) prior to the installation of the turbulator. in ), length of the installation section where the turbulator is installed ($L_ t $), and length of the downstream section after the installation of the ripturbulator (L out The ratio of ) is limited to 10~14 : 6~12 : 25~35, and a plurality of rip turbators are installed spaced apart from each other along the flow direction on one surface of the front end of the internal cooling channel of the gas turbine, wherein each of the plurality of rip turbators has a width (e), a height (h), and a length (l) and is formed to protrude from one surface of the internal cooling channel of the gas turbine, and has an asymmetric zigzag arrangement structure including a plurality of first rip turbators spaced apart along the flow direction and having a longitudinal direction in the first lateral direction of the center line, which is the center in the width direction of the internal cooling channel of the gas turbine, and a plurality of second rip turbators located between each of the plurality of first rip turbators, spaced apart along the flow direction, and having a longitudinal direction in the second lateral direction of the center line, wherein the pitch (P), which is the flow direction spacing distance between the plurality of rip turbators, is limited to a range of 6 to 10 times the width (e), and A turbulence generator for cooling gas turbine blades, characterized in that the height (h) is structured to be in the range of 0.8 to 1.2 times the width (e), and the length (l) is structured to be in the range of 15 to 25 times the width (e). Claim 9 delete Claim 10 delete Claim 11 delete Claim 12 delete Claim 13 delete Claim 14 A turbulence generator for cooling gas turbine blades, characterized in that, in claim 8, the height is 0.04 to 0.06 relative to the height of the cooling channel.

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