Combustors and generators containing them

Abstract

To improve cooling efficiency of a cooling fluid flowing through a cooling flow passage.SOLUTION: The combustor includes a liner (140) extending in a longitudinal direction, a transition piece extending in the longitudinal direction of the liner (140) and overlapping an end of the liner (140) at a predetermined interval, and a shroud (170) coupled to the liner (140) between the liner (140) and the transition piece, wherein inner surfaces of the liner (140) and the shroud (170) form a cooling-passage 170P, and the cooling-passage 170P is configured such that air flowing inside becomes turbulent for heat dissipation from the liner (140).SELECTED DRAWING: Figure 4

Description

Technical Field

[0001] The present invention relates to a combustor and a generator including the same. More specifically, the present invention relates to a combustor and a generator configured such that a turbulent flow is formed in a cooling flow path for cooling a liner of the combustor.

Background Art

[0002] A gas turbine is a power generation engine that mixes and burns compressed air compressed by a compressor with fuel, and rotates a turbine with high-temperature gas generated by the combustion. The gas turbine is used to drive a generator, an aircraft, a ship, a train, and the like.

[0003] Generally, a gas turbine includes a compressor, a combustor, and a turbine. The compressor inhales and compresses external air and then transfers it to the combustor. The air compressed by the compressor becomes in a high-pressure and high-temperature state. The combustor mixes and burns the compressed air flowing in from the compressor with fuel. The combustion gas generated by the combustion is discharged to the turbine. The turbine blades inside the turbine are rotated by the combustion gas, and thereby power is generated. The generated power is used in various fields such as power generation and driving of mechanical devices.

[0004] The combustion chamber of the combustor may be exposed to a high-temperature environment. The liner forming the combustion chamber needs to be prevented from melting or being damaged by the high temperature of the combustion chamber. For this purpose, a cooling flow path through which a cooling fluid can flow can be formed outside the liner to cool the liner. The cooling fluid that has passed through the cooling flow path, particularly air, can move to the combustion chamber and supply oxygen necessary for combustion.

[0005] However, when an excessive amount of air is provided to the cooling flow path, a problem may occur in that the power generation amount decreases because a part of the air that should generate electricity in the turbine is diverted to the cooling flow path to form a cooling fluid. Further, when an excessive amount of air flows into the combustion chamber, a problem may occur in that a large amount of nitrogen oxides (NOx) is generated and the environment is polluted.

Summary of the Invention

[0006] The present invention was made to solve the above-mentioned problems, and its objective is to improve the cooling efficiency of the cooling fluid flowing through the cooling channel. This reduces the amount of cooling fluid flowing through the cooling channel and thus reduces the generation of nitrogen oxides.

[0007] The technical challenges that this document aims to address are not limited to those mentioned above, and other technical challenges not mentioned can be clearly understood by a person with ordinary skill in the art to which this disclosure pertains from the following description. [Means for solving the problem]

[0008] A combustor according to one embodiment of the present invention includes a liner that forms a combustion chamber and extends along its length, a transition piece that overlaps the liner at a predetermined distance from the end of the liner and extends along the length of the liner, and a shroud that is coupled to the liner between the liner and the transition piece, wherein the inner surfaces of the liner and the shroud form a cooling channel, and the cooling channel is configured such that the air flowing inside becomes turbulent in order to release heat from the liner.

[0009] The system may further include turbulators that protrude from the inner surface of the liner or shroud toward the cooling channel. The turbulator is contained within the liner, which includes a channel forming section that forms a cooling channel, and the turbulator can protrude from the channel forming section.

[0010] The turbulator may be perpendicular to the length of the cooling channel. Multiple turbulators can be provided, arranged at predetermined intervals along the length of the cooling channel.

[0011] Let e ​​be the length of the protrusions of multiple turbulators, and p be the distance between multiple turbulators, and the ratio of e to p may be between 8 and 10. The shroud may include a swirler configured to form a swirl in an inlet channel that communicates with the inlet of the cooling channel.

[0012] The inner surface of the swahl forms an inlet channel, and the inlet channel may have a longitudinal direction that is inclined with respect to the longitudinal direction of the cooling channel. The inlet channel may have a longitudinal direction that combines two directions perpendicular to the longitudinal direction of the cooling channel. The distance between the two furthest points in the cross-sectional area of ​​the swahl may be greater than or equal to the height of the cooling channel.

[0013] The outlet channel of the cooling channel can extend along the length of the cooling channel. With respect to the direction in which the cooling fluid, configured to flow through the cooling channel, flows within the cooling channel, the cooling channel may have, at least in part, a section in which its cross-sectional area is smaller in the direction from upstream to downstream. Sections of the cooling channel with a smaller cross-sectional area can be provided by creating steps or other differences in height.

[0014] The system further includes turbulators protruding from the inner surface of the liner or shroud toward the cooling channel, and sections where the cross-sectional area of ​​the cooling channel is small can correspond to sections where the turbulators are formed. A strut may be further included between the shroud and the liner, configured to support the shroud and the liner.

[0015] A combustor according to one embodiment of the present invention includes a liner that forms a combustion chamber and extends along its length, a transition piece that overlaps the liner at a predetermined distance from the end of the liner and extends along the length of the liner, and a shroud that is coupled to the liner between the liner and the transition piece, wherein the inner surfaces of the liner and the shroud form a cooling channel, and the cooling channel may have, at least in part, a section in which the cross-sectional area decreases in the direction from upstream to downstream.

[0016] Sections of the cooling channel with a smaller cross-sectional area can be provided by creating steps or other differences in height. The system further includes turbulators protruding from the inner surface of the liner or shroud toward the cooling channel, and sections where the cross-sectional area of ​​the cooling channel is small can correspond to sections where the turbulators are formed. The shroud may include a swirler configured to form a swirl in an inlet channel that communicates with the inlet of the cooling channel.

[0017] A generator according to one embodiment of the present invention includes a compressor, a turbine configured to produce electricity using air compressed by the compressor, and a combustor configured to burn the air compressed by the compressor, wherein the combustor includes a liner that forms a combustion chamber and extends along its length, a transition piece that overlaps the liner at a predetermined distance from the end of the liner and extends along the length of the liner, and a shroud coupled to the liner between the liner and the transition piece, wherein the inner surfaces of the liner and the shroud form a cooling channel, and the cooling channel is configured such that the air flowing inside becomes turbulent in order to release heat from the liner. [Effects of the Invention]

[0018] In one embodiment of the present invention, the cooling efficiency of the liner can be improved by shaping the cooling channel so that turbulence is formed in the combustor. In one embodiment of the present invention, a combustor is formed with a cooling channel that has improved cooling efficiency, thereby allowing less air to flow into the combustion chamber and reducing the generation of nitrogen oxides.

[0019] In the combustor according to one embodiment of the present invention, a cooling flow path having a smaller cross-sectional area in the flow direction is formed, so that the air flowing into the combustion chamber can be reduced. The generator according to one embodiment of the present invention includes the above combustor, and thus the above effects can be obtained.

[0020] The effects obtained by the present invention are not limited to the effects mentioned above, and other effects not mentioned can be clearly understood by those having ordinary knowledge in the technical field to which the present disclosure belongs from the following description.

Brief Description of the Drawings

[0021] [Figure 1] It is a cross-sectional view of a generator according to the first embodiment of the present invention. [Figure 2] It is a cross-sectional view of the combustor shown in FIG. 1. [Figure 3] It is a cross-sectional perspective view of a comparative example of a portion corresponding to the rear end portion of the liner shown in FIG. 2. [Figure 4] It is a cross-sectional view showing an enlarged view of the liner and the shroud with respect to the rear end portion of the liner shown in FIG. 2. [Figure 5] It is an enlarged perspective view showing an enlarged view of the ends of the liner and the shroud shown in FIG. 4. [Figure 6] It is a cross-sectional perspective view showing a cross-section of the liner and the shroud shown in FIG. 4 cut along the length direction of the inlet flow path. [Figure 7] It is an enlarged cross-sectional view showing an enlarged view of the turbulator shown in FIG. 4. [Figure 8] It is a graph regarding the cooling efficiency with respect to the protruding height and the interval of a plurality of turbulators shown in FIG. 7. [Figure 9] It is a cross-sectional view of a liner and a shroud according to the second embodiment of the present invention. [Figure 10] It is a cross-sectional view of a liner and a shroud according to the third embodiment of the present invention. [Figure 11] It is a cross-sectional view of a liner and a shroud according to the fourth embodiment of the present invention. [Figure 12] This is a cross-sectional view of the liner and shroud according to a fifth embodiment of the present invention. [Figure 13] This is a cross-sectional view of the liner and shroud according to the sixth embodiment of the present invention. [Figure 14] This is a cross-sectional view of the liner and shroud according to the seventh embodiment of the present invention. [Modes for carrying out the invention]

[0022] Preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings, so that they can be easily implemented by a person with ordinary skill in the art to which the present invention pertains. However, the present invention can be realized in a variety of different forms and is not limited or restricted by the following embodiments.

[0023] In order to clearly explain the present invention, detailed descriptions of related prior art that are irrelevant to the description or that would unnecessarily obscure the essence of the invention have been omitted. In this specification, when assigning reference numerals to components in each drawing, the same or similar reference numerals shall be assigned to components that are the same or similar throughout the specification.

[0024] Furthermore, the terms and words used in this specification and in the claims should not be interpreted in a manner limited to their ordinary or dictionary meanings, but rather should be interpreted in a manner consistent with the technical idea of ​​the present invention, in accordance with the principle that inventors may appropriately define the concepts of terms in order to best describe their invention.

[0025] The various embodiments and terminology used herein are not intended to limit the technical features described herein to any particular embodiment, but should be understood to include various modifications, equivalents, or substitutes of such embodiments.

[0026] In relation to the description of the drawings, similar or related components may be given similar reference numerals. The singular form of a noun corresponding to an item may include one or more of those items unless the context clearly indicates otherwise.

[0027] In this document, each phrase such as “A or B,” “at least one of A and B,” “at least one of A or B,” “A, B, or C,” “at least one of A, B, and C,” and “at least one of A, B, or C” may include any one of the items listed together with the phrase in question, or any possible combination thereof.

[0028] The term "and / or" includes a combination of multiple related listed components, or any one of the components of multiple related listed components.

[0029] Terms such as "first," "second," "first," or "second" may be used simply to distinguish one component from others and not to limit it in any other respect (e.g., importance or order).

[0030] When one component (e.g., the first) is referred to as "coupled" or "connected" to another component (e.g., the second) with or without the terms "functionally" or "communically", this means that the first component can be connected to the other component directly (e.g., by wire), wirelessly, or via the third component.

[0031] Terms such as "contains" or "has" indicate the presence of features, figures, steps, actions, components, parts, or combinations thereof described in this document, but do not preclude the possibility of the presence or addition of one or more other features, figures, steps, actions, components, parts, or combinations thereof.

[0032] The term "connected," "joined," "supported," or "in contact" between one component and another includes not only cases where the components are directly connected, joined, supported, or in contact, but also cases where they are indirectly connected, joined, supported, or in contact through a third component.

[0033] One element is said to be "on top of" another element, not only when one element is in contact with another, but also when there is yet another element between the two elements.

[0034] On the other hand, terms such as "vertical direction," "lower side," and "front-to-back direction" used in the following explanation are defined based on the drawings, and these terms do not limit the shape and position of each component. Embodiments of the present invention will be described in detail below with reference to the attached drawings.

[0035] First Embodiment Figure 1 is a cross-sectional view of a generator 1 according to a first embodiment of the present invention. Figure 2 is a cross-sectional view of the combustor 100 shown in Figure 1.

[0036] A generator 1 can be provided to generate electricity. Since generator 1 can obtain electricity by burning gas, it can be called a gas turbine 20. The thermodynamic cycle of generator 1 can ideally follow the Brayton cycle. The Brayton cycle can consist of four processes: isentropic compression (adiabatic compression), constant-pressure rapid heating, isentropic expansion (adiabatic expansion), and constant-pressure heat dissipation. That is, atmospheric air is drawn in and compressed to high pressure, then fuel is burned in a constant-pressure environment to release thermal energy, this high-temperature combustion gas is expanded and converted into kinetic energy, and then exhaust gas containing residual energy is released into the atmosphere. In other words, the cycle can be carried out in four processes: compression, heating, expansion, and heat dissipation.

[0037] The generator 1 that realizes the Brayton cycle as described above may include a compressor 10, a combustor 100, and a turbine 20, as shown in Figure 1. While the following description will refer to Figure 1, the description of the present invention can also be broadly applied to turbine 20 engines having a configuration equivalent to the generator 1 illustrated in Figure 1.

[0038] Referring to Figure 1, the compressor 10 of the generator 1 can draw in air from the outside and compress it. The compressor 10 can supply compressed air, compressed by the compressor blades 10, to the combustor 100, and can also supply cooling air to high-temperature regions in the generator 1 that require cooling. In this process, the inhaled air undergoes an adiabatic compression process in the compressor 10, so the pressure and temperature of the air that has passed through the compressor 10 increase.

[0039] The compressor 10 can be designed as a centrifugal compressor 10 or an axial compressor 10. While a centrifugal compressor 10 is used for a small generator 1, a large generator 1, such as the one shown in Figure 1, requires the compression of a large volume of air, so a multi-stage axial compressor 10 is generally used. In this case, the compressor blades 10 rotate in conjunction with the rotation of the rotor disc, compressing the incoming air and moving the compressed air to the subsequent stages. The air is gradually compressed to a high pressure as it passes through the multi-stage compressor blades 10.

[0040] The compressor 10 can be driven using a portion of the power output from the turbine 20. For this purpose, as shown in Figure 1, the rotating shaft of the compressor 10 and the rotating shaft of the turbine 20 can be directly connected. In the case of a large generator 1, approximately half of the output produced by the turbine 20 can be used to drive the compressor 10. Therefore, improving the efficiency of the compressor 10 will have a direct impact on improving the overall efficiency of the generator 1.

[0041] The turbine 20 can generate electricity using the gas burned by the combustor 100. The gas moving inside the turbine 20 can generate electricity by rotating the turbine blades.

[0042] The combustor 100 can mix compressed air supplied from the outlet of the compressor 10 with fuel and perform isobaric combustion to generate high-energy combustion gases. As shown in Figure 2, the combustor 100 may include a nozzle 110, a nozzle housing 111, and / or a combustor 100 housing.

[0043] The nozzle housing 111 surrounds and houses the nozzle 110 and can have a substantially circular cylindrical shape. The nozzle 110 is located downstream of the compressor 10 and can be arranged along the annular nozzle housing 111. In the nozzle 110, fuel and air are mixed in an appropriate ratio before being injected, creating a state suitable for combustion. That is, the nozzle 110 can be configured to generate a flame. Furthermore, the nozzle housing 111 can form an air chamber into which air enters. More specifically, as will be described later, air moving from the compressor 10 along the outer surface of the combustor 100 housing can enter the air chamber of the nozzle housing 111. The air that enters the air chamber is supplied to the nozzle 110 and can be mixed with the air so that the nozzle 110 generates a flame. Furthermore, the air that enters the air chamber can move toward the effusion plate, which will be described later and is located downstream of the air chamber, and can cool the effusion plate.

[0044] The combustor 100 housing can have a combustion chamber 140S formed inside where a combustion reaction occurs for the combustion of gas. Furthermore, the combustor 100 housing can connect the nozzle 110 and the turbine 20, and transmit the gas burned by the nozzle 110 to the turbine 20. The combustor 100 housing connects the nozzle 110 and the turbine 20, allowing high-temperature combustion gas to flow. In this process, compressed air flows along the outer surface of the combustor 100 housing and is supplied to the nozzle 110 side, and in this process the combustor 100 housing, which has been heated by the high-temperature combustion gas, can be properly cooled. Furthermore, here, the compressed air can be understood as a cooling fluid containing other fluids.

[0045] More specifically, the combustor 100 housing may include a liner 140 that forms a combustion chamber 140S, and a transition piece 160 (see Figure 3) configured to guide the flame formed and propagating in the liner 140 toward the turbine 20. That is, the liner 140 may be located adjacent to the nozzle 110 and upstream with respect to the direction of flame propagation, while the transition piece 160 may be located downstream of the liner 140. In other words, it may form a combustion chamber 140S and extend along its length. The transition piece 160 may overlap the liner 140 at a predetermined distance from its end and extend along the length of the liner 140. The liner 140 and the transition piece 160 are located inside the combustor 100 housing and may therefore be called the inner housing. Furthermore, the liner 140 and the transition piece 160 may extend along their length while maintaining a circular cross-section. In other words, the liner 140 and the transition piece 160 can be seen as having a kind of tubular shape.

[0046] The combustor 100 housing may include a fluid sleeve 150 located outside the liner 140 and the transition piece 160, configured to cover the liner 140 and the transition piece 160. The fluid sleeve 150 can be formed at a predetermined distance from the liner 140 and the transition piece 160. A flow path is formed between the fluid sleeve 150 and the liner 140, or between the fluid sleeve 150 and the transition piece 160, and compressed air flows along this flow path as described above, thereby allowing the compressed air to cool the liner 140 and / or the transition piece 160. In this process, some of the compressed air, compressed by the compressor 10, can escape and move through a hole formed in the fluid sleeve 150 towards the flow path formed between the fluid sleeve 150 and the liner 140, or between the fluid sleeve 150 and the transition piece 160. In particular, the liner 140 and the transition piece 160 are components that come into contact with the flame formed by the combustion of fuel injected from the nozzle 110, and therefore their temperature can become high, requiring cooling. The liner 140 and the transition piece 160 can be made of metal. In this case, since metals melt at temperatures above their melting point, it is necessary to keep the temperature of the liner 140 and the transition piece 160 below their melting point in order to maintain their original shape.

[0047] Of these, the rear end portion of the liner 140 is particularly susceptible to significant temperature increases due to the flame, as this is where the flame matures. Therefore, cooling of the rear end portion of the liner 140 is necessary. The cooling problem of the liner 140 will be explained in more detail below.

[0048] Figure 3 is a cross-sectional perspective view of a comparative example of the portion corresponding to the rear end portion of the liner shown in Figure 2. A comparative example of the present invention will be described with reference to Figure 3. The following description of the comparative example is provided for the purpose of making the present invention easier to explain. Therefore, it goes without saying that the description of the comparative example will not limit the scope of the present invention or make any part of it unusable as an embodiment.

[0049] Furthermore, the following description applies to parts corresponding to the configurations of the embodiments of the present invention. Therefore, the configurations of embodiments relating to comparative examples will be described without reference numerals in the drawings.

[0050] To cool the rear end of the liner, an overlapping section between the liner and the transition piece can be provided. This allows compressed air moving along the outer surfaces of the liner and the transition piece to move between the liner and the transition piece. Since the space between the liner and the transition piece can be located in the area corresponding to the rear end of the liner, the flow of compressed air in this area can help with heat transfer at the rear end of the liner. In particular, since heat transfer occurs more through flowing fluids than through still air, a flow can be formed in the adjacent area for heat release at the rear end of the liner.

[0051] In this case, a shroud may be included that is configured to form a cooling channel through which a cooling fluid flows adjacent to the rear end portion of the liner. The shroud can be coupled to the liner between the liner and the transition piece. In this case, the inner surfaces of the liner and the shroud can form a cooling channel. Since the cooling channel extends along the outer surface of the liner, the cooling fluid flowing along the cooling channel can help dissipate heat from the outer surface of the liner. In this case, the portion previously described as the rear end portion of the liner, i.e., the portion that contributes to the formation of the cooling channel, can be defined as the channel forming portion. The liner may include a channel forming portion that defines the cooling channel.

[0052] The shroud can form an inlet passage connected to the cooling fluid inlet. With reference to Figure 3, the inlet passage can extend downward. The shroud can form an outlet passage connected to the cooling passage outlet. The outlet passage may include, for example, a first outlet passage formed along the length of the cooling passage with reference to Figure 3, and a second outlet passage extending upward and toward the combustion chamber. The cooling fluid can flow in the order of the inlet passage, the cooling passage, and the outlet passage.

[0053] Referring to Figure 3, it can be seen that dots are marked on the channel formation area. An experiment was conducted in which the temperature was measured at each of the dots marked on the channel formation area. The dots were numbered 1 to 8 from left to right, and the results are summarized in the table below.

[0054] Before that, the environmental conditions for the experiment are as follows: The Turbine Inlet Temperature (TIT) is 1650°C, and the temperature of the cooling fluid entering the inlet channel is 493°C. The cooling channel, designed to account for the melting point of the metal, cools the liner to a target temperature of 815°C. The Thermal Barrier Coating (TBC) thickness is 1.5 mm. The thermal conductivity of the TBC is 1.2 W / m / C. The mass flow rate of the compressed air used as the cooling fluid is 1.213 kg / s.

[0055] [Table 1]

[0056] The results above show that there are parts of the liner that exceed the target temperature of 815°C. This causes the following three problems. Firstly, the liner's temperature approaches its melting point, which can lead to melting or thermal deformation problems. Secondly, the steep temperature distribution of the liner can cause warping due to differences in deformation at each temperature. Thirdly, if more compressed air is introduced into the cooling channel to solve this problem, more air is injected into the combustion chamber, as compressed air is supplied to the combustion chamber. More air can lead to the problem of increased nitrogen oxide production during combustion.

[0057] An embodiment of the present invention that solves this problem is described below. To begin with, the experimental results of the first embodiment compared with the comparative example are as follows. The mass flow rate of the compressed air used as the cooling fluid in the first embodiment was 0.8873 kg / s, which is smaller than the mass flow rate of the compressed air used in the comparative example. In the first embodiment, the mass flow rate of the compressed air was numerically 0.3257 kg / s less, and proportionally 0.706 times more was used compared to the comparative example. Furthermore, the cooling effect of a smaller mass flow rate is greater, as follows.

[0058] [Table 2]

[0059] Figure 4 is a cross-sectional view showing the liner and shroud enlarged relative to the rear end portion of the liner shown in Figure 2. Figure 5 is an enlarged perspective view showing the ends of the liner 140 and shroud 170 shown in Figure 4. Figure 6 is a cross-sectional perspective view showing the liner 140 and shroud 170 shown in Figure 4 cut along the length of the inlet flow path 171P.

[0060] Referring to Figures 4 to 6, a liner 140 and a shroud 170 according to one embodiment of the present invention will be described. As explained earlier in the comparative example, I will explain the overlapping parts again in order to clearly explain one embodiment of the present invention.

[0061] The combustor 100 may include a liner 140 that forms a combustion chamber 140S and extends along its length. The combustor 100 may include a transition piece 160 that overlaps the liner 140 at a predetermined distance from its end and extends along its length. The combustor 100 may include a shroud 170 that is coupled to the liner 140 between the liner 140 and the transition piece 160. The inner surfaces of the liner 140 and the shroud 170 can form a cooling channel 170P.

[0062] To solve the aforementioned problems, the cooling efficiency of the cooling fluid flowing through the cooling channel 170P can be improved. For this purpose, the cooling channel 170P can be configured such that the air flowing inside becomes turbulent in order to release heat from the liner 140. Flow can be classified into laminar flow and turbulent flow. When it is turbulent, heat transfer can be much better than when it is laminar flow. By configuring the flow before it enters the cooling channel 170P as laminar flow, energy loss due to the flow can be minimized, and by configuring only the direct flow that cools the liner 140 as turbulent, the cooling efficiency of the liner 140 can be greatly increased. The present invention can be seen as including any method that makes the flow of the cooling fluid flowing through the cooling channel 170P turbulent.

[0063] A first embodiment, represented as one embodiment of the present invention, can incorporate the following ideas to make the flow in the cooling channel 170P turbulent: First, a turbulator 142 that protrudes toward the cooling channel 170P. Second, a swirler 171 configured to generate a swirl in the inlet channel 171P. Third, a step is created to reduce the cross-section of the channel. Reducing the cross-section of the channel must be explained in consideration of the idea of ​​supplying less air to the combustion chamber 140S, which will be described later, and will be explained in more detail along with related explanations.

[0064] First, the turbulator 142 will be described. The combustor 100 may further include a turbulator 142 that protrudes from the inner surface of the liner 140 or shroud 170 toward the cooling channel 170P. The turbulator 142 may, but is not limited to, protruding from the liner 140 as shown in Figure 4. This allows the cooling fluid flowing through the cooling channel 170P to collide with the turbulator 142 and form turbulence.

[0065] In particular, the turbulator 142 can be included in the liner 140. The aforementioned liner 140 may include a channel forming section 141 that forms the cooling channel 170P. The turbulator 142 can protrude from the channel forming section 141. Since the turbulator 142 must affect the cooling fluid flowing through the cooling channel 170P, it is preferable that it be formed in the channel forming section 141 that forms the cooling channel 170P.

[0066] The turbulator 142 may be perpendicular to the longitudinal direction of the cooling channel 170P. For example, as shown in Figure 5, it can extend along the circumferential direction of the liner 140. This allows the transition of the cooling channel 170P to turbulence to be more active, as the turbulator 142 protrudes in a direction that perpendicularly blocks the movement of the cooling fluid when the cooling fluid flowing through the cooling channel 170P moves along the longitudinal direction of the liner 140. However, considering this, if the cooling fluid flowing through the cooling channel 170P flows at a predetermined angle to the longitudinal direction of the cooling channel 170P, the extension direction of the turbulator 142 can have a predetermined angle with the longitudinal direction of the liner 140, taking into account the predetermined angle formed between the cooling fluid and the cooling channel 170P, in order to activate the transition of the cooling fluid to turbulence.

[0067] Multiple turbulators 142 can be provided, arranged along the length of the cooling channel 170P at predetermined intervals. This allows for a continuous transition of the cooling fluid to turbulence along the length of the cooling channel 170P. The relationship between the degree of protrusion of the turbulators 142 and the spacing between multiple turbulators 142 will be explained in more detail with reference to Figures 7 and 8.

[0068] The shroud 170 may include a swirler 171 configured to form a swirl in an inlet channel 171P that communicates with the inlet of the cooling channel 170P. Here, swirl is as understood by the ordinary art and is considered to be understood in this disclosure. There are various structures for forming a swirl, and the present invention is considered to encompass all such ideas for forming a swirl. In one embodiment, as shown in Figure 6, the inner surface of the swirler 171 may form an inlet channel 171P, and the inlet channel 171P may have a longitudinal direction inclined with respect to the longitudinal direction of the cooling channel 170P. More specifically, with reference to Figure 6, the inlet channel 171P may extend in a direction that adds a left-right component to the direction downward relative to the cooling channel 170P. That is, the inlet channel 171P may have a longitudinal direction that combines two directions perpendicular to the longitudinal direction of the cooling channel 170P. This allows a swirl to be formed in the process because the cooling fluid flowing through the inlet channel 171P undergoes a change of direction as it flows along the cooling channel 170P. Furthermore, the swara 171 can be formed by milling.

[0069] The distance between the two furthest points in the cross-sectional area of ​​the swahl 171 may be greater than or equal to the height of the cooling channel 170P. In other words, the cross-sectional area of ​​the inlet channel 171P can be greater than the cross-sectional area of ​​the corresponding cooling channel 170P. Since one cooling channel 170P can correspond to multiple inlet channels 171P, the total cross-sectional area of ​​the cooling channels 170P can be greater than the cross-sectional area of ​​one inlet channel 171P. However, when comparing the effective flow cross-sectional area of ​​the actual cooling channel 170P through which the cooling fluid that has actually exited the inlet channel 171P flows with the cross-sectional area of ​​the inlet channel 171P, the effective cross-sectional area of ​​the cooling channel 170P can be smaller. Because the cross-sectional area of ​​the inlet channel 171P is greater than the cross-sectional area of ​​the cooling channel 170P, the velocity of the flow through the inlet channel 171P can be slower than that of the cooling channel 170P. That is, the pressure of the cooling fluid in the cooling channel 170P is lower than the pressure of the cooling fluid flowing through the inlet channel 171P. The pressure difference allows the cooling fluid to move naturally from the inlet channel 171P to the cooling channel 170P. As a result, the movement of the cooling fluid to the inlet channel 171P can occur naturally without the need for any other device to provide a driving force.

[0070] The outlet passage 172P of the cooling passage 170P can extend along the length of the cooling passage 170P. Compared to the comparative example, the number of outlet passages 172P can be reduced, thereby reducing the amount of air moving into the combustion chamber 140S. Furthermore, by directing the air injected into the combustion chamber 140S toward the flame, the amount of air participating in the combustion reaction can be reduced. This reduces the amount of nitrogen oxides formed in the combustion chamber 140S.

[0071] As shown in Figure 4, the cooling channel 170P can have a section, at least in part, where the cross-sectional area is smaller in the direction from upstream to downstream, based on the direction in which the cooling fluid configured to flow through the cooling channel 170P flows within the cooling channel 170P. This reduces the amount of air supplied to the combustion chamber 140S. In particular, since the air flowing through the cooling channel 170P is neither ideal air nor laminar flow, the amount of air supplied to the combustion chamber 140S can be reduced by reducing the cross-sectional area. Furthermore, since the side with the smaller cross-sectional area is downstream, as with the relationship between the inlet channel 171P and the cooling channel 170P described above, the pressure of the cooling fluid is lower downstream than upstream, and the pressure difference allows air to naturally move from upstream to downstream.

[0072] In sections where the cross-sectional area of ​​the cooling channel 170P is reduced, a step can be formed. This allows for a more active transition of the cooling fluid flow to turbulence. Furthermore, the process of reducing the cross-sectional area by forming a step can be made easier. One surface of the shroud 170 forming the cooling channel 170P is designated as the first cooling channel surface 170Aa, and one surface of the shroud 170 located downstream of the first cooling channel surface 170Aa is designated as the second cooling channel surface 170Ab. In this case, the second cooling channel surface 170Ab can be located closer to the liner 140 than the first cooling channel surface 170Aa. Furthermore, the first cooling channel surface 170Aa can be located adjacent to the second cooling channel surface 170Ab, with a step formed between them.

[0073] The section of the cooling channel 170P where the cross-sectional area is small can correspond to the section where the turbulators 142 are formed. That is, multiple turbulators 142 can be formed in the section of the cooling channel 170P where the cross-sectional area is small. As shown in Figure 4, the portion of the cooling channel 170P directly connected to the inlet channel 171P can have a larger cross-sectional area than the portion formed downstream. Turbulators 142 can be formed in the section where the cross-sectional area is formed to decrease in the direction toward the downstream. This is because the reduced cross-sectional area and the resulting turbulence can reduce the amount of air flowing into the combustion chamber 140S.

[0074] Referring to Figure 5, the combustor according to the present invention may further include a strut 173 between the shroud 170 and the liner 140, configured to support the shroud 170 and the liner 140. The strut 173 may have a cylindrical shape. The strut 173 may be located downstream of the cooling passage 170P. That is, the strut 173 may be formed adjacent to the outlet passage 172P. As shown in Figure 4, on the left side of the shroud 170, the shroud 170 and the liner 140 are in contact, so the gap between the liner 140 and the shroud 170 on the left side of the cooling passage 170P is less likely to narrow, and its height is easily maintained. However, on the right side of the cooling passage 170P, the liner 140 and the shroud 170 are not supported by each other, so the height of the cooling passage 170P is difficult to maintain unless supported by the strut 173.

[0075] Figure 7 is an enlarged cross-sectional view showing the turbulator 142 shown in Figure 4. Figure 8 is a graph showing the cooling efficiency in relation to the protrusion height and spacing of the multiple turbulators 142 shown in Figure 7.

[0076] A turbulator 142 according to one embodiment of the present invention will be described with reference to Figures 7 and 8. As shown in Figure 4, multiple turbulators 142 can be provided. Of course, the multiple turbulators 142 may each have different protruding heights, and the spacing between adjacent turbulators 142 may also differ. However, in the following explanation, we will assume that each turbulator 142 has the same protruding height and the same spacing between adjacent turbulators 142.

[0077] The length of the protruding turbulators 142 can be defined as e, and the distance between the turbulators 142 can be defined as p. Figure 8 is a graph summarizing the results of experiments conducted to determine efficient values ​​for e and p. The x-axis corresponds to the p / e value, and the y-axis corresponds to the Nusselt number. More specifically, the Nusselt number ratio shown on the y-axis is the Nusselt number in turbulent flow divided by the Nusselt number in laminar flow. It can be seen that the higher the Nusselt number ratio, the higher the cooling efficiency. Looking at the graph, it can be seen that the cooling efficiency is high when the ratio of e to p is between 8 and 10. Therefore, the ratio of e to p in one embodiment of the present invention may be between 8 and 10.

[0078] The following describes embodiments different from the first embodiment. We will omit as much of the content common to the first embodiment as possible, and focus on the differences when describing the other embodiments. In other words, it is clear that any information not described in the other embodiments can be supplemented by the content of the first embodiment.

[0079] Second Embodiment Figure 9 is a cross-sectional view of the liner 140 and shroud 170 according to a second embodiment of the present invention.

[0080] Referring to Figure 9, a turbulator 142-1 according to a second embodiment of the present invention will be described. In the second embodiment, the extension start position of the turbulator 142-1 differs from that of the first embodiment.

[0081] The turbulator 142-1 can extend from the shroud 170. In this case, the shroud 170 and the turbulator 142-1 can be formed as a single unit.

[0082] Third Embodiment Figure 10 is a cross-sectional view of the liner 140 and shroud 170 according to a third embodiment of the present invention.

[0083] Referring to Figure 10, a turbulator 142-2 according to a third embodiment of the present invention will be described. The third embodiment differs from the first embodiment in that the shape of the turbulator 142-2 is different.

[0084] The turbulator 142-2 can extend from the liner 140 to the shroud 170. In this case, holes can be formed in the turbulator 142-2 through which the cooling fluid can pass.

[0085] The holes in turbulator 142 through which the cooling fluid can pass can be formed at a different height than the holes in the adjacent turbulator 142-2, and configured to make the transition of the cooling fluid to turbulence more active.

[0086] Fourth Embodiment Figure 11 is a cross-sectional view of the liner 140 and shroud 170 according to a fourth embodiment of the present invention.

[0087] Referring to Figure 11, the turbulator 142-3 according to the fourth embodiment of the present invention will be described. The fourth embodiment differs from the first embodiment in that the shape of the turbulator 142-3 is different.

[0088] The turbulator 142-3 can be provided as a groove. The turbulator 142-3 can be provided as a groove so that the cooling fluid contained in the groove transitions to turbulence. The turbulator 142-3 of the third embodiment has the advantage of reducing fluid energy loss compared to the turbulator 142 of the first embodiment.

[0089] Fifth Embodiment Figure 12 is a cross-sectional view of the liner 140 and shroud 170 according to the fifth embodiment of the present invention.

[0090] A fifth embodiment of the present invention, the swala 171, will be described with reference to Figure 12. In the fifth embodiment, the shape of the swara 171-4 differs from that of the first embodiment.

[0091] The swaa 171-4 may have a protruding shape. The swaa 171-4 may extend in a direction that rotates with respect to the direction in which the inlet channel 171P extends, with respect to the direction in which the inlet channel 171P extends as the axis of rotation, and may have a shape that protrudes toward the axis of rotation.

[0092] Furthermore, the swaara 171-4 may have a groove shape. The extension direction of the groove can be similarly described in relation to the extension direction of the protruding shape described above.

[0093] Sixth Embodiment Figure 13 is a cross-sectional view of the liner 140 and shroud 170 according to the sixth embodiment of the present invention.

[0094] Referring to Figure 13, the cooling channel surface 170A-5 according to the sixth embodiment of the present invention will be described. The sixth embodiment differs from the first embodiment in that the method of reducing the cross-sectional area of ​​the cooling channel 170P does not form a step.

[0095] The cooling channel 170P may include a section in which the cross-sectional area decreases from upstream to downstream. For this reason, the cooling channel surface 170A-5 of the shroud 170 can approach the liner 140 downstream. The cooling channel surface 170A-5 may be linearly sloped, as shown in Figure 13, or it may have a curved surface with a fluctuating slope, as shown in Figure 13.

[0096] Seventh Embodiment Figure 14 is a cross-sectional view of the liner 140 and shroud 170 according to the seventh embodiment of the present invention.

[0097] Referring to Figure 14, the outlet channel 172P according to the seventh embodiment of the present invention will be described. The seventh embodiment differs from the first embodiment in that the number and direction of the outlet channels 172P are different.

[0098] The outlet passage 172P may include a first outlet passage 172Pa-6 as described in the first embodiment, and a second outlet passage 172Pb-6 that extends at a predetermined angle with respect to the extension direction of the first outlet passage 172Pa-6. Since the extension direction of the second outlet passage 172Pb-6 is toward the combustion chamber 140S, air can flow toward the flame.

[0099] Unless expressly noted, the embodiments described above can be combined with other embodiments. Or, in combinations of one embodiment with another, it should be assumed that combinations between embodiments are possible unless expressly limited. Combinations of one embodiment with another are deemed to be disclosed herein.

[0100] Although the present invention has been described above with reference to limited embodiments and drawings, the present invention is not limited thereto, and various implementations are possible by persons with ordinary skill in the art to which the present invention pertains, within a scope equivalent to the technical concept of the present invention and the claims described later. [Explanation of Symbols]

[0101] 1: Generator 10: Compressor 20: Turbine 100: Combustor 110: Nozzle 111: Nozzle Housing 140: Raina 140S: Combustion chamber 141: Flow channel forming section 142: Turbulator 150: Fluid Sleeve 160: Transition Piece 170: Shroud 170P: Cooling channel 170A: Cooling channel surface 170Aa: 1st cooling channel surface 170Ab: 2nd cooling channel surface 171: Swara 171P: Inlet channel 172P: Outlet channel 172 Pa: First outlet channel 172Pb: Second outlet channel 173: Strut

Claims

1. A liner that forms the combustion chamber and extends along its length, A transition piece overlaps the liner at a predetermined distance from its end and extends along the length of the liner, Between the liner and the transition piece, a shroud is coupled to the liner, Includes, The inner surfaces of the liner and the shroud form cooling channels. The cooling channel is configured such that the air flowing inside becomes turbulent in order to release heat from the liner. The shroud includes a swirl configured such that a swirl is formed in an inlet channel communicating with the inlet of the cooling channel. Combustion device.

2. The combustor according to claim 1, further comprising a turbulator protruding from the inner surface of the liner or the shroud toward the cooling channel.

3. The turbulator is included in the liner, The liner includes a channel forming portion that forms the cooling channel, The combustor according to claim 2, wherein the turbulator protrudes from the flow path forming portion.

4. The combustor according to claim 2, wherein the turbulator is perpendicular to the longitudinal direction of the cooling channel.

5. The combustor according to claim 2, wherein a plurality of turbulators are provided so as to be arranged along the length of the cooling channel at predetermined intervals.

6. Let e ​​be the length over which the multiple turbulators protrude. Let p be the interval between the multiple turbulators. The combustor according to claim 5, wherein the ratio of e to p is 8 or more and 10 or less.

7. A combustion device, A liner that forms a combustion chamber and extends along its length, A transition piece overlaps the liner at a predetermined distance from its end and extends along the length of the liner, Between the liner and the transition piece, a shroud is coupled to the liner, Includes, The inner surfaces of the liner and the shroud form cooling channels. The cooling channel is configured such that the air flowing inside becomes turbulent in order to release heat from the liner. The combustor further includes a plurality of turbulators in the cooling channel that extend from the liner to the shroud along the direction from the liner to the shroud, The plurality of turbulators are arranged at intervals from each other along the length of the cooling channel, Each of the plurality of turbulators has a hole that connects the upstream cooling channel and the downstream cooling channel in the longitudinal direction of the cooling channel, Of the plurality of turbulators, the holes formed in each turbulator that are adjacent to each other in the longitudinal direction of the cooling channel are arranged at different positions in the direction from the liner toward the shroud. Combustion device.

8. The combustor according to claim 7, wherein the shroud includes a swirl configured such that a swirl is formed in an inlet passage that communicates with the inlet of the cooling passage.

9. A liner that forms a combustion chamber and extends along its length, A transition piece overlaps the liner at a predetermined distance from its end and extends along the length of the liner, Between the liner and the transition piece, a shroud is coupled to the liner, Includes, The inner surfaces of the liner and the shroud form cooling channels. The cooling channel is configured such that the air flowing inside becomes turbulent in order to release heat from the liner. Multiple turbulators are formed on the inner surface of the liner or shroud, which are provided as multiple recesses that open into the cooling passage. Each of the plurality of grooves extends in a direction intersecting the longitudinal direction of the cooling channel and is configured to accommodate at least a portion of the air flowing through the cooling channel and to transform the air into turbulent flow. Combustion device.

10. The combustor according to claim 9, wherein the shroud includes a swirl configured such that a swirl is formed in an inlet passage communicating with the inlet of the cooling passage.

11. The inner surface of the swahl forms the inlet channel, The combustor according to claim 10, wherein the inlet passage has a length direction inclined with respect to the length direction of the cooling passage.

12. The combustor according to claim 10, wherein the inlet passage has a longitudinal direction that combines two directions perpendicular to the longitudinal direction of the cooling passage.

13. The combustor according to claim 10, wherein the distance between the two furthest points of the cross-sectional area of ​​the swahl is greater than or equal to the height of the cooling channel.

14. The combustor according to claim 1, wherein the outlet channel of the cooling channel extends along the longitudinal direction of the cooling channel.

15. With reference to the direction in which the cooling fluid, configured to flow through the aforementioned cooling channel, flows within the cooling channel, The combustor according to any one of claims 1 to 14, wherein the cooling channel has at least a portion of a section in which the cross-sectional area decreases with respect to the direction from upstream to downstream.

16. The combustor according to claim 15, wherein the section of the cooling channel in which the cross-sectional area becomes smaller is provided with a step.

17. The system further includes a turbulator that protrudes from the inner surface of the liner or shroud toward the cooling channel, The combustor according to claim 15, wherein the section of the cooling channel in which the cross-sectional area becomes smaller corresponds to the section in which the turbulator is formed.

18. The combustor according to any one of claims 1 to 14, further comprising a strut between the shroud and the liner, configured to support the shroud and the liner.

19. A liner that forms a combustion chamber and extends along its length, A transition piece overlaps the liner at a predetermined distance from its end and extends along the length of the liner, Between the liner and the transition piece, a shroud is coupled to the liner, Includes, The inner surfaces of the liner and the shroud form cooling channels. The cooling channel has, at least in part, a section in which the cross-sectional area decreases with respect to the direction from upstream to downstream. The combustor includes a shroud which includes a swirl configured such that a swirl is formed in an inlet passage that communicates with the inlet of the cooling passage.

20. The combustor according to claim 19, wherein the section of the cooling channel in which the cross-sectional area becomes smaller is provided with a step.

21. The system further includes a turbulator that protrudes from the inner surface of the liner or shroud toward the cooling channel, The combustor according to claim 19 or 20, wherein the section of the cooling channel in which the cross-sectional area becomes smaller corresponds to the section in which the turbulator is formed.

22. Compressor and, A turbine configured to produce electricity using air compressed by the aforementioned compressor, A combustor configured to burn air compressed by the aforementioned compressor, Includes, The aforementioned combustor is A liner that forms a combustion chamber and extends along its length, A transition piece overlaps the liner at a predetermined distance from its end and extends along the length of the liner, Between the liner and the transition piece, a shroud is coupled to the liner, Includes, The inner surfaces of the liner and the shroud form cooling channels. The cooling channel is configured such that the air flowing inside becomes turbulent in order to release heat from the liner. A generator wherein the shroud includes a swirler configured such that a swirl is formed in an inlet passage communicating with the inlet of the cooling passage.

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