Combustion chamber flame tube and optimization method for distribution of cooling holes of combustion chamber flame tube

Abstract

The invention relates to a combustion chamber flame tube and a cooling hole distribution optimization method thereof. The combustion chamber flame tube comprises the first tube wall and the second tube wall, the cooling hole with the large first included angle is formed in the high-heat-load area, so that the large included angle is formed between the flowing direction of cooling air introduced by the cooling hole and the main flow direction, the cooling air is not prone to converging into the main flow, and the cooling air can be better attached to the wall face of the high-heat-load area; and a cooling air film with a large contact area with the inner wall of the barrel is formed, and the risk of local high-temperature ablation caused by insufficient cooling of a high-heat load area is reduced. The cooling holes with the small first included angle are adopted in the low-heat-load area, so that the included angle between the flowing direction of cooling air introduced by the cooling holes and the main flow direction is small, the cooling air is better converged with the main flow, the low-heat-load area is prevented from being overcooled, the temperature distribution of the inner wall of the flame tube is uniform, and the service life of the flame tube is prolonged. The problems of thermal fatigue and the like caused by overlarge temperature gradient are solved, and the risk of failure of the flame tube is reduced.

Description

Technical Field

[0001] The present application relates to the technical field of combustion chambers, and in particular to a method for optimizing the distribution of combustion chamber flame tubes and cooling holes thereof. Background Art

[0002] The combustion chamber flame tube is a device in which the fuel burns directly. It has the characteristics of high combustion temperature and poor cooling conditions. It is an indispensable part of industrial combustion devices such as aircraft engines and gas turbines.

[0003] Since the temperature of the combustion chamber flame tube is relatively high, it is necessary to cool the inside of the combustion chamber flame tube to avoid damage to the combustion chamber flame tube.

[0004] In the related art, discrete cooling holes are generally evenly arranged on the flame tube, and the cooling holes penetrate the wall of the flame tube, so that the cold side air can enter the flame tube through the cooling holes and form a wall-attached air film on the inner wall of the flame tube to block the heat exchange between the high-temperature gas and the flame tube. The flame tube wall temperature is reduced by suction heat exchange on the cold air side, enhanced heat exchange in the hole, and air film cooling on the inner wall to prevent the flame tube from failing. However, this method still has the problem of low cooling efficiency, which can easily lead to flame tube failure. Summary of the invention

[0005] Based on this, it is necessary to provide a combustion chamber flame tube to address the problem that the existing flame tube is prone to failure.

[0006] A combustion chamber flame tube, the combustion chamber flame tube comprising:

[0007] A cylinder, wherein the cylinder is provided with a plurality of groups of cooling holes along its own axial direction, wherein the plurality of cooling holes in the same group are evenly spaced along the circumference of the cylinder, and the orthographic projection of the geometric center line of the cooling hole on the tangent plane of the inner circumferential wall of the cylinder has a first angle with the central axis of the cylinder;

[0008] The cylinder body includes a first cylinder wall and a second cylinder wall distributed along its own axial direction, the temperature of the first cylinder wall is lower than the temperature of the second cylinder wall; the first angle of the cooling hole located in the first cylinder wall is lower than the first angle of the cooling hole located in the second cylinder wall.

[0009] In one embodiment, the first included angles of at least two groups of cooling holes located on the first barrel wall are different; and / or,

[0010] The first included angles of at least two groups of cooling holes located on the second cylinder wall are different.

[0011] In one of the embodiments, along the mainstream flow direction of the combustion chamber flame tube, two adjacent groups of cooling holes are respectively defined as a front group of cooling holes and a rear group of cooling holes; the cooling air film formed by the front group of cooling holes flows between two adjacent cooling holes in the rear group of cooling holes.

[0012] In one embodiment, the axial spacing between two adjacent groups of cooling holes located on the first cylinder wall is greater than the axial spacing between two adjacent groups of cooling holes located on the second cylinder wall.

[0013] In one embodiment, the axial spacing between two adjacent groups of cooling holes on the first cylinder wall is different from the axial spacing between two adjacent groups of cooling holes on the first cylinder wall; and / or,

[0014] The axial spacing between two adjacent groups of cooling holes on the second cylinder wall is different from the axial spacing between two adjacent groups of cooling holes on the second cylinder wall.

[0015] In one embodiment, along the flow direction of the main flow of the combustion chamber flame tube, the first tube wall corresponds to the upstream area and the downstream area of ​​the main flow;

[0016] The second cylinder wall corresponds to a region between the upstream region and the downstream region of the main flow.

[0017] In one embodiment, the cylinder is provided with a plurality of main combustion holes at intervals along its circumference, and the main combustion holes and the cooling holes are arranged at intervals along the axial direction of the cylinder;

[0018] The cylinder is provided with a plurality of mixing holes at intervals along its circumferential direction, and the mixing holes and the cooling holes are arranged at intervals along the axial direction of the cylinder.

[0019] A method for optimizing the distribution of cooling holes of a combustion chamber flame tube, the combustion chamber flame tube comprising a cylinder, the cylinder having a plurality of groups of cooling holes evenly distributed along its axial direction, the method comprising:

[0020] Determine the diameter of the cooling hole, the first angle, and the distance between two adjacent cooling holes; the first angle is defined as: the angle between the orthographic projection of the geometric center line of the cooling hole on the tangent plane of the inner peripheral wall of the cylinder and the central axis of the cylinder;

[0021] Establishing a three-dimensional model of the cylinder;

[0022] Obtaining the wall temperature distribution of the cylinder;

[0023] According to the wall temperature distribution of the cylinder, adjusting the axial spacing between two adjacent groups of cooling holes;

[0024] According to the wall temperature distribution of the cylinder, adjusting the first angle of the cooling hole;

[0025] Obtaining the wall temperature distribution of the cylinder;

[0026] Repeatedly adjust the axial spacing between two adjacent groups of cooling holes and / or adjust the first angle of the cooling holes until the wall temperature of the cylinder is evenly distributed along the axial direction of the cylinder.

[0027] In one embodiment, the method of establishing the three-dimensional model of the cylinder includes: establishing the three-dimensional model of the cylinder using three-dimensional modeling software;

[0028] The method for obtaining the wall temperature distribution of the cylinder comprises: using fluid simulation analysis software to perform simulation analysis on the three-dimensional model of the cylinder to obtain the wall temperature distribution of the cylinder.

[0029] In one embodiment, according to the wall temperature distribution of the cylinder, the method for adjusting the first angle of the cooling hole includes:

[0030] Dividing the cylinder into a first cylinder wall and a second cylinder wall, wherein the wall temperature of the second cylinder wall is greater than the wall temperature of the first cylinder wall;

[0031] Along the axial direction of the cylinder, two to four groups of cooling holes are selected corresponding to the positions of the second cylinder wall, and the first angle of the two to four groups of cooling holes is increased; and / or, along the axial direction of the cylinder, two to four groups of cooling holes are selected corresponding to the positions of the first cylinder wall, and the first angle of the two to four groups of cooling holes is reduced;

[0032] The first included angles of other groups of cooling holes distributed along the axial direction of the cylinder are determined according to a preset curve, which includes a multi-function curve, a Bezier curve or a spline curve.

[0033] The above-mentioned combustion chamber flame tube includes a first tube wall and a second tube wall. The temperature of the first tube wall is lower than the temperature of the second tube wall, that is, the first tube wall is a low heat load area, and the second tube wall is a high heat load area. By arranging a cooling hole with a larger first angle in the high heat load area, a larger angle is formed between the flow direction of the cooling air introduced by the cooling hole and the mainstream direction, and the cooling air is not easy to merge into the mainstream, and the contact area with the tube wall is increased. Therefore, the cooling air can better adhere to the wall surface of the high heat load area to form a cooling air film with a larger contact area with the inner wall of the tube, so as to reduce the wall temperature of the high heat load area, realize the efficient use of cooling air, improve the cooling effect, and reduce the risk of local high-temperature ablation caused by insufficient cooling in the high heat load area. At the same time, by using cooling holes with a smaller first angle in the low heat load area, the angle between the cooling air flow direction introduced by the cooling hole and the mainstream direction is smaller, which can better merge with the mainstream, avoiding overcooling in the low heat load area, achieving on-demand cooling of the wall temperature and uniform coverage of the air film, and making the temperature distribution of the inner wall of the flame tube more uniform, thereby solving problems such as thermal fatigue caused by excessive temperature gradient, improving the durability of the flame tube, and reducing the risk of flame tube failure. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 A schematic diagram of a combustion chamber flame tube provided in an embodiment of the present application.

[0035] Figure 2 for Figure 1 A partial schematic diagram of the combustion chamber flame tube is shown.

[0036] Figure 3 for Figure 2 A partial schematic diagram of the cooling holes of the combustion chamber flame tube is shown.

[0037] Figure 4 for Figure 3 Schematic diagram of the cooling holes of the combustion chamber flame tube shown.

[0038] Figure 5 for Figure 2 A partial schematic diagram of the combustion chamber flame tube is shown.

[0039] Figure 6 A partial schematic diagram of a combustion chamber flame tube provided in another embodiment of the present application.

[0040] Figure 7 A flow chart of a method for optimizing the distribution of cooling holes in a combustion chamber flame tube provided in one embodiment of the present application.

[0041] Figure 8 A curve diagram of a first included angle of a cooling hole provided in an embodiment of the present application.

[0042] Reference numerals: 100, cylinder; 110, cooling hole; 120, first cylinder wall; 130, second cylinder wall; 140, main combustion hole; 150, mixing hole; 210, cyclone. DETAILED DESCRIPTION

[0043] In order to make the above-mentioned purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are described in detail below in conjunction with the accompanying drawings. In the following description, many specific details are set forth to facilitate a full understanding of the present application. However, the present application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without violating the connotation of the present application, so the present application is not limited by the specific embodiments disclosed below.

[0044] In the description of the present application, it should be understood that if the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. appear, the orientation or position relationship indicated by these terms is based on the orientation or position relationship shown in the accompanying drawings, which is only for the convenience of describing the present application and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application.

[0045] In addition, if the terms "first" or "second" appear, these terms are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of the features. In the description of this application, if the term "plurality" appears, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0046] In this application, unless otherwise clearly specified and limited, if the terms "installed", "connected", "connected", "fixed" and the like appear, these terms should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integrated connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to the specific circumstances.

[0047] In the present application, unless otherwise clearly specified and limited, if there is a description that a first feature is "above" or "below" a second feature, etc., or similar descriptions appear, it may mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediate medium. Moreover, the first feature being "above", "above" and "above" the second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. The first feature being "below", "below" and "below" the second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0048] It should be noted that if an element is referred to as being "fixed to" or "disposed on" another element, it may be directly on the other element or there may be a central element. If an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. If any, the terms "vertical", "horizontal", "upper", "lower", "left", "right" and similar expressions used in this application are for illustrative purposes only and do not represent the only implementation method.

[0049] See also Figures 1 to 3 As shown, a combustion chamber flame tube provided in an embodiment of the present application includes a cylinder 100, and the cylinder 100 is provided with a plurality of groups of cooling holes 110 along its own axial direction. The plurality of cooling holes 110 in the same group are evenly spaced along the circumference of the cylinder 100, and the orthographic projection of the geometric center line of the cooling hole 110 on the tangent plane of the inner circumferential wall of the cylinder 100 has a first angle β with the central axis of the cylinder 100, as shown in FIG. Figure 3 As shown, a dotted rectangle schematically illustrates a cross section of the inner circumferential wall of the cylinder 100; the cylinder 100 includes a first cylinder wall 120 and a second cylinder wall 130 distributed along its own axial direction, and the temperature of the first cylinder wall 120 is lower than the temperature of the second cylinder wall 130; the first angle of the cooling hole 110 located in the first cylinder wall 120 is lower than the first angle of the cooling hole 110 located in the second cylinder wall 130. The cooling hole 110 penetrates the cylinder wall of the cylinder 100 and is connected to the inner cavity of the cylinder 100, and the external cooling gas enters the inner cavity of the cylinder 100 through the cooling hole 110. The direction indicated by the arrow X is the mainstream direction in the combustion chamber, which is also the axial direction of the cylinder 100.

[0050] In the above-mentioned combustion chamber flame tube, the temperature of the first tube wall 120 is lower than the temperature of the second tube wall 130, that is, the first tube wall 120 is a low heat load area, and the second tube wall 130 is a high heat load area. By setting a cooling hole 110 with a larger first angle in the high heat load area, a larger angle is made between the flow direction of the cooling air introduced by the cooling hole 110 and the mainstream direction, and the cooling air is not easy to merge into the mainstream, and the contact area with the tube wall is increased. Therefore, the cooling air can better adhere to the wall surface of the high heat load area to form a cooling air film with a larger contact area with the inner wall of the cylinder 100, so as to reduce the wall temperature of the high heat load area, thereby realizing efficient utilization of cooling air, improving cooling effect, and reducing the risk of local high-temperature ablation caused by insufficient cooling in the high heat load area. At the same time, by using the cooling hole 110 with a smaller first angle in the low heat load area, the angle between the cooling air flow direction introduced by the cooling hole 110 and the mainstream direction is smaller, which can better merge with the mainstream, avoiding overcooling in the low heat load area, achieving on-demand cooling of the wall temperature and uniform coverage of the air film, and making the temperature distribution of the inner wall of the flame tube more uniform, thereby solving problems such as thermal fatigue caused by excessive temperature gradient, improving the durability of the flame tube, and reducing the risk of flame tube failure.

[0051] like Figure 1 As shown, in some embodiments, the barrel 100 may be cylindrical. In other embodiments, the barrel 100 may be annular, rectangular, flat, or curved.

[0052] like Figure 1 As shown, in some embodiments, the cross-section of the cooling hole 110 is circular, and the diameter is between 0.3 mm and 2 mm. In some embodiments, the diameter of the cooling hole 110 is 0.3 mm, and in other embodiments, the diameter of the cooling hole 110 is 2 mm. In other embodiments, the cross-section of the cooling hole 110 can be rectangular or irregular.

[0053] like Figure 1 As shown, in some embodiments, the number of groups of cooling holes 110 arranged in the axial direction may range from 5 to 40. In some embodiments, at the same axial position, the number of cooling holes 110 arranged in each group in the circumferential direction is 12 to 100, and the plurality of cooling holes 110 are evenly arranged in the circumferential direction.

[0054] like Figure 4As shown, in some embodiments, there is a second angle α between the geometric center line of the cooling hole 110 and the section of the inner circumferential wall of the cylinder 100, and the second angle α can be 10 degrees-60 degrees. For example, in one embodiment, the second angle α of the cooling hole 110 is 10 degrees. In one embodiment, the second angle α of the cooling hole 110 is 30 degrees. In one embodiment, the second angle α of the cooling hole 110 is 60 degrees. The cooling effect is improved by selecting a suitable second angle. Generally speaking, the smaller the second angle, the better the cooling effect, but small angles are limited by processing difficulty and punching accuracy.

[0055] See also Figure 6 As shown, in one embodiment, the first angles of at least two groups of cooling holes 110 distributed along the axial direction on the first barrel wall 120 are different, and correspondingly, the barrel wall temperatures corresponding to the two groups of cooling holes 110 are different. In some embodiments, the first angles of at least two groups of cooling holes 110 on the second barrel wall 130 are different. As mentioned above, by setting a smaller first angle for the cooling holes 110 in the low heat load area and a larger first angle for the cooling holes 110 in the high heat load area, the corresponding cooling requirements can be met.

[0056] In one embodiment, along the axial direction of the barrel 100, each group of cooling holes 110 adopts a different first angle, for example, Figure 6 In the illustrated embodiment, the first angles of the plurality of cooling holes 110 increase first and then decrease along the axial direction, wherein β1 to β12 are 50°, 55°, 60°, 65°, 70°, 75°, 80°, 85°, 90°, 90°, 80°, and 70°, respectively.

[0057] See also Figure 5 As shown, in one embodiment, along the flow direction of the main flow of the combustion chamber flame tube, two adjacent groups of cooling holes 110 are respectively defined as the front group of cooling holes 110 and the rear group of cooling holes 110; the cooling air film formed by the front group of cooling holes 110 flows between two adjacent cooling holes 110 in the rear group of cooling holes 110. Figure 5 Arrows are used to indicate the flow direction of the cooling film. This arrangement avoids repeated stacking of the cooling film, achieves uniform coverage of the cooling film, avoids overcooling or undercooling of the wall, and reduces the maximum wall temperature and temperature gradient.

[0058] See also Figure 2As shown, in one embodiment, the axial spacing between two adjacent groups of cooling holes 110 located on the first barrel wall 120 is greater than the axial spacing between two adjacent groups of cooling holes 110 located on the second barrel wall 130. That is, the axial spacing of the cooling holes 110 in the high heat load area is smaller than the axial spacing of the cooling holes 110 in the low heat load area. In the high heat load area, by reducing the axial spacing of the cooling holes 110, the flow rate of the introduced cooling gas is increased, the cooling effect on the high heat load area is improved, the uniformity of the temperature distribution on the inner wall of the barrel 100 is improved, and the risk of failure of the combustion chamber flame tube is reduced.

[0059] In some embodiments, the axial spacing between two adjacent groups of cooling holes 110 is 5 mm to 30 mm. In some embodiments, the axial spacing between two adjacent groups of cooling holes 110 located on the second cylinder wall 130 is 5 mm. In some embodiments, the axial spacing between two adjacent groups of cooling holes 110 located on the first cylinder wall 120 is 30 mm.

[0060] See also Figure 5 As shown, in one embodiment, the axial spacing between two adjacent groups of cooling holes 110 located on the first barrel wall 120 is different from the axial spacing between two adjacent groups of cooling holes 110. In some embodiments, the axial spacing between two adjacent groups of cooling holes 110 located on the second barrel wall 130 is different from the axial spacing between two adjacent groups of cooling holes 110. By arranging the cooling holes 110 unevenly on the barrel 100, local high temperatures can be effectively reduced, cooling air can be fully and efficiently utilized, and local overcooling or undercooling can be avoided. For example, Figure 6 In the embodiment shown, the values ​​of L1, L2, L3 and L4 are 20 mm, 12 mm, 8 mm and 14 mm respectively.

[0061] See also Figure 1 and Figure 6 As shown, in one embodiment, the inner wall surface of the cylinder 100 of the combustion chamber flame tube has different heat load distributions, and along the mainstream direction, the temperature distribution of the inner wall surface of the cylinder 100 shows a trend of first increasing and then decreasing. That is, the first cylinder wall 120 in the low heat load area corresponds to the upstream area and downstream area of ​​the mainstream; the second cylinder wall 130 in the high heat load area corresponds to the area between the upstream area and the downstream area of ​​the mainstream.

[0062] For the low heat load area, the axial spacing of the cooling holes 110 is larger and the first angle is smaller. The cooling air film has a larger axial momentum and fully utilizes the momentum to cover the axial direction to achieve uniform and efficient air film cooling. For the high heat load area, the axial spacing of the cooling holes 110 is small and a larger first angle is used. The enhanced heat exchange, air film cooling and other effects in the holes are focused on a shorter axial range, and the local cooling effect is stronger, which can enhance the wall cooling in the high heat load area.

[0063] See also Figure 1 and Figure 6 As shown, in one embodiment, the cylinder 100 is provided with a plurality of main combustion holes 140 at intervals along its circumference, and the main combustion holes 140 and the cooling holes 110 are spaced and evenly arranged along the axial direction of the cylinder 100. Figure 1 In the illustrated embodiment, the number of the main combustion holes 140 is 6. Of course, the number of the main combustion holes 140 is not limited thereto and can be set according to actual needs.

[0064] The main combustion hole 140 is usually located in the upstream area of ​​the cylinder 100, and is used to inject fuel (gas fuel or liquid fuel) into the combustion chamber, which is mixed with air to form a combustible mixture, which helps to achieve an efficient combustion process and ensure that the fuel can be quickly and completely burned in the combustion chamber, thereby generating the required thrust or power output.

[0065] See also Figure 1 and Figure 6 As shown, the cylinder 100 is provided with a plurality of mixing holes 150 at intervals along its circumference, and the mixing holes 150 and the cooling holes 110 are spaced and evenly arranged along the axial direction of the cylinder 100. Figure 1 In the illustrated embodiment, the number of the mixing holes 150 is 12. Of course, the number of the mixing holes 150 is not limited thereto and can be set according to actual needs.

[0066] The mixing hole 150 is usually located in the downstream area of ​​the cylinder 100. In the later stage of the combustion process, the cold air introduced through the mixing hole 150 can effectively dilute the high-temperature combustion gas, thereby reducing the local temperature peak and avoiding local overheating. The air introduced through the mixing hole 150 can further refine the fuel droplets and increase the contact area between the fuel and oxygen to achieve a more thorough combustion reaction, improve combustion efficiency, and control the combustion temperature. In this way, it not only helps to extend the service life of the combustion chamber flame tube and other high-temperature components, but also reduces the impact of thermal stress on the material. At the same time, the cold air introduced through the mixing hole 150 can significantly reduce the maximum temperature of the combustion area, thereby reducing the amount of nitrogen oxides generated.

[0067] like Figure 1As shown, in some embodiments, a swirler 210 is also provided at the head of the combustion chamber flame tube. The swirler 210 includes a plurality of obliquely arranged blades, which can convert the air entering in a straight line into an airflow with a strong rotational motion. By introducing a swirl, the air moves in a spiral path, which increases the turbulence intensity, thereby greatly promoting the mixing effect between the fuel and the air. At the same time, the recirculation zone formed by the swirl can create a relatively stable combustion area inside the combustion chamber flame tube, and the stability of the flame can be maintained even if the external conditions change (such as pressure fluctuations). Furthermore, the appropriate swirl intensity can help to homogenize the temperature field in the flame tube, avoid local overheating, and extend the service life of the flame tube and other high-temperature components.

[0068] In some embodiments, a nozzle (not shown) is also provided at the head of the combustion chamber flame tube for spraying fuel into the combustion chamber. For liquid fuel, the nozzle is responsible for breaking it into tiny droplets, increasing the surface area, accelerating the evaporation rate, further promoting mixing with air, and making it well atomized, which helps to achieve faster and more thorough combustion of the fuel. The swirler 210 and the nozzle work together. The swirl generated by the swirler 210 enhances the contact opportunity between the fuel and the air, while the nozzle provides precise fuel supply and atomization, ensuring the optimal mixing ratio of fuel and air, and forming a stable and efficient combustion environment.

[0069] Furthermore, an embodiment of the present application also provides a method for optimizing the distribution of cooling holes of a combustion chamber flame tube, wherein the combustion chamber flame tube includes a cylinder 100, and the cylinder 100 has multiple groups of cooling holes 110 evenly distributed along its axial direction. The method includes:

[0070] Step S100, determining the aperture of the cooling hole 110, the first angle and the distance between two adjacent cooling holes 110; the first angle is defined as: the angle between the orthographic projection of the geometric center line of the cooling hole 110 on the tangent plane of the inner wall of the cylinder 100 and the central axis of the cylinder 100.

[0071] Among them, the size of the combustion chamber flame tube and the distribution of cooling air volume that need to be optimized can be determined based on experience, so that the circulation area of ​​the cooling air can be calculated, and then the aperture of the cooling hole 110 can be selected. The aperture of the cooling hole 110 can be between 0.3mm-2mm, and specifically 0.5mm, 0.7mm or 1mm can be selected. After determining the cooling air volume distribution and the aperture of the cooling hole 110, the number of holes can be calculated, so that the appropriate number of groups and the number of cooling holes 110 corresponding to each group can be selected. After selecting the appropriate first angle and second angle for the cooling holes 110, the baseline scheme of the combustion chamber flame tube can be obtained. In the baseline scheme, multiple groups of cooling holes 110 are evenly arranged along the axial direction, that is, the axial spacing is the same as the first angle.

[0072] Step S200 , establishing a three-dimensional model of the cylinder 100 .

[0073] Among them, a physical three-dimensional model of the combustion chamber flame tube can be established according to actual needs, or a three-dimensional model of the combustion chamber flame tube can be established using three-dimensional modeling software (such as SolidWorks).

[0074] Step S300, obtaining the wall temperature distribution of the cylinder 100.

[0075] Among them, taking the use of 3D modeling software to establish a 3D model as an example, after the 3D model is established, the established 3D model is subjected to fluid simulation analysis by fluid simulation analysis software (such as Fluent), so as to obtain the wall temperature distribution of the cylinder 100 at different axial positions. In some embodiments, the wall temperature distribution of the cylinder 100 can be presented in the form of a cloud map, for example, a high heat load area is presented in red, a low heat load area is presented in blue, and the like.

[0076] Step S400 , adjusting the axial distance between two adjacent groups of cooling holes 110 according to the wall temperature distribution of the cylinder 100 .

[0077] Specifically, after obtaining the wall temperature distribution of the cylinder 100, the high wall temperature area (high heat load area) and the low wall temperature area (low heat load area) are determined by analyzing the change in the circumferential average wall temperature. For the high wall temperature area, that is, the high heat load area, the axial spacing of the cooling holes 110 is reduced, thereby increasing the flow rate of the cooling gas introduced, improving the cooling effect on the high heat load area, improving the uniformity of the temperature distribution on the inner wall of the cylinder 100, and reducing the risk of failure of the combustion chamber flame tube. For the low wall temperature area, that is, the low heat load area, the axial hole spacing is increased, thereby reducing the flow rate of the cooling gas introduced and reducing the risk of overcooling.

[0078] Step S500 , adjusting the first angle of the cooling hole 110 according to the wall temperature distribution of the cylinder 100 .

[0079] Through the above-mentioned simulation analysis, the circumferential average wall temperature at different axial positions of the combustion chamber flame tube and the flow field information near the outlet of the cooling hole 110 can be measured. According to the wall temperature, the cylinder 100 is divided into the first cylinder wall 120 and the second cylinder wall 130. The low wall temperature area corresponds to the first cylinder wall 120, and the high wall temperature area corresponds to the second cylinder wall 130. The first angle of the cooling hole 110 located in the second cylinder wall 130 (that is, the high wall temperature area) is increased. According to the flow field information such as the flow velocity in the hole, the flow direction of the cooling gas, the mainstream flow velocity and the mainstream direction, the approximate streamline of the cooling gas film can be determined, and the appropriate first angle is selected according to the streamline, so that the streamline of the cooling gas film of the first group of cooling holes 110 flows through the middle of the two adjacent cooling holes 110 of the latter group.

[0080] Step S600, obtaining the wall temperature distribution of the cylinder 100.

[0081] Specifically, the simulation analysis is re-performed on the optimized combustion chamber flame tube to obtain the wall temperature distribution of the tube body 100 .

[0082] When the difference in the wall temperature distribution of the cylinder 100 is still large, step S700 is adopted to repeatedly adjust the axial spacing between two adjacent groups of cooling holes 110 and / or adjust the first angle of the cooling holes 110 until the wall temperature of the cylinder 100 is evenly distributed along the axial direction of the cylinder 100.

[0083] That is to say, step S500 may be iterated multiple times to achieve the initial optimization requirement, so as to reduce the local high temperature and make the wall temperature of the cylinder 100 evenly distributed.

[0084] In one embodiment, 2 to 4 control points may be selected, that is, the first angles of the cooling holes 110 at 2 to 4 axial positions may be changed, and the first angles of the cooling holes 110 at the remaining axial positions may be determined by the curve formed by the control points. In some embodiments, two to four groups of cooling holes 110 located in a high heat load area, i.e., the second barrel wall 130, may be selected, and the first angles of the two to four groups of cooling holes 110 may be increased. In some embodiments, two to four groups of cooling holes 110 located in a low heat load area, i.e., the first barrel wall 120, may be selected, and the first angles of the two to four groups of cooling holes 110 may be reduced, and the first angles of the other groups of cooling holes 110 distributed along the axial direction may be determined according to a preset curve. Figure 8 As shown, the curve can be a multi-function curve, a Bezier curve, a spline curve, etc. Thus, the multi-dimensional variables formed by the multiple groups of cooling holes 110 can be simplified to 2-4 variables, which greatly shortens the optimization time, and at the same time retains the overall trend of the first angle change to reduce the high wall temperature point of the cylinder 100, and realize the requirement of uniform distribution of the wall temperature of the cylinder 100, so as to obtain a flame tube with efficient cooling under as few tests or simulation calculations as possible.

[0085] By setting a cooling hole 110 with a larger first angle in the high heat load area, the cooling air flow direction introduced by the cooling hole 110 has a larger angle with the mainstream direction, the cooling air is not easy to merge into the mainstream, and the contact area with the cylinder wall is increased, so the cooling air can better adhere to the wall surface of the high heat load area, forming a cooling air film with a larger contact area with the inner wall of the cylinder 100, so as to reduce the wall temperature of the high heat load area, realize the efficient use of cooling air, improve the cooling effect, and reduce the risk of local high temperature ablation caused by insufficient cooling in the high heat load area. At the same time, by using a cooling hole 110 with a smaller first angle in the low heat load area, the cooling air flow direction introduced by the cooling hole 110 has a smaller angle with the mainstream direction, better merges with the mainstream, avoids overcooling of the low heat load area, realizes on-demand cooling of the wall temperature and uniform coverage of the air film, and makes the temperature distribution of the inner wall of the flame tube more uniform, thereby solving problems such as thermal fatigue caused by excessive temperature gradient, improving the durability of the flame tube, and reducing the risk of flame tube failure.

[0086] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0087] The above embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the patent application. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent application shall be subject to the attached claims.

Claims

1. A combustion chamber flame tube, characterized in that: The combustion chamber flame tube comprises: A cylinder (100), wherein the cylinder (100) is provided with a plurality of groups of cooling holes (110) along its own axial direction, wherein the plurality of cooling holes (110) in the same group are evenly spaced along the circumference of the cylinder (100), and an orthographic projection of a geometric center line of the cooling hole (110) on a tangent plane of an inner circumferential wall of the cylinder (100) forms a first angle with a central axis of the cylinder (100); The cylinder (100) comprises a first cylinder wall (120) and a second cylinder wall (130) distributed along the cylinder's axial direction, the temperature of the first cylinder wall (120) being lower than the temperature of the second cylinder wall (130); and the first angle of the cooling hole (110) located in the first cylinder wall (120) being lower than the first angle of the cooling hole (110) located in the second cylinder wall (130).

2. The combustion chamber flame tube according to claim 1, characterized in that: The first included angles of at least two groups of cooling holes (110) located on the first barrel wall (120) are different; and / or, The first included angles of at least two groups of cooling holes (110) located on the second cylinder wall (130) are different.

3. The combustion chamber flame sleeve according to claim 1, characterized in that: Along the flow direction of the mainstream of the combustion chamber flame tube, two adjacent groups of cooling holes (110) are respectively defined as a front group of cooling holes (110) and a rear group of cooling holes (110); a cooling air film formed by the front group of cooling holes (110) flows between two adjacent cooling holes (110) in the rear group of cooling holes (110).

4. The combustion chamber flame tube according to claim 1, characterized in that: The axial spacing between two adjacent groups of cooling holes (110) located on the first barrel wall (120) is greater than the axial spacing between two adjacent groups of cooling holes (110) located on the second barrel wall (130).

5. The combustion chamber flame sleeve according to claim 1, characterized in that: The axial spacing between two adjacent groups of cooling holes (110) located on the first barrel wall (120) is different from the axial spacing between two adjacent groups of cooling holes (110); and / or, The axial spacing between two adjacent groups of cooling holes (110) located on the second cylinder wall (130) is different from the axial spacing between two adjacent groups of cooling holes (110) located on the second cylinder wall (130).

6. The combustion chamber flame sleeve according to claim 1, characterized in that: Along the flow direction of the main flow of the combustion chamber flame tube, the first tube wall (120) corresponds to the upstream area and the downstream area of ​​the main flow; The second cylinder wall (130) corresponds to the area between the upstream area and the downstream area of ​​the main flow.

7. The combustion chamber flame liner according to claim 1, characterized in that: The cylinder (100) is provided with a plurality of main combustion holes (140) at intervals along its circumferential direction, and the main combustion holes (140) and the cooling holes (110) are arranged at intervals along the axial direction of the cylinder (100); The cylinder (100) is provided with a plurality of mixing holes (150) at intervals along its circumference, and the mixing holes (150) and the cooling holes (110) are arranged at intervals along the axial direction of the cylinder (100).

8. A method for optimizing the distribution of cooling holes of a combustion chamber flame tube, the combustion chamber flame tube comprising a cylinder (100), the cylinder (100) having a plurality of groups of cooling holes (110) evenly distributed along its axial direction, characterized in that: The method comprises: Determining the diameter of the cooling hole (110), a first angle, and the spacing between two adjacent cooling holes (110); the first angle is defined as: the angle between the orthographic projection of the geometric center line of the cooling hole (110) on the tangent plane of the inner circumferential wall of the cylinder (100) and the central axis of the cylinder (100); Establishing a three-dimensional model of the cylinder (100); Obtaining the wall temperature distribution of the cylinder (100); According to the wall temperature distribution of the cylinder (100), adjusting the axial spacing between two adjacent groups of cooling holes (110); adjusting a first angle of the cooling hole (110) according to the wall temperature distribution of the barrel (100); Obtaining the wall temperature distribution of the cylinder (100); Repeatedly adjusting the axial spacing between two adjacent groups of cooling holes (110) and / or adjusting the first angle of the cooling holes (110) until the wall temperature of the cylinder (100) is evenly distributed along the axial direction of the cylinder (100).

9. The optimization method according to claim 8, characterized in that: The method for establishing a three-dimensional model of the cylinder (100) comprises: establishing a three-dimensional model of the cylinder (100) using three-dimensional modeling software; The method for obtaining the wall temperature distribution of the cylinder (100) comprises: using fluid simulation analysis software to perform simulation analysis on a three-dimensional model of the cylinder (100) to obtain the wall temperature distribution of the cylinder (100).

10. The optimization method according to claim 8, characterized in that: The method of adjusting the first angle of the cooling hole (110) according to the wall temperature distribution of the cylinder (100) comprises: The cylinder (100) is divided into a first cylinder wall (120) and a second cylinder wall (130), wherein the wall temperature of the second cylinder wall (130) is greater than the wall temperature of the first cylinder wall (120); Along the axial direction of the cylinder (100), two to four groups of cooling holes (110) are selected corresponding to the position of the second cylinder wall (130), and the first angle of the two to four groups of cooling holes (110) is increased; and / or, along the axial direction of the cylinder (100), two to four groups of cooling holes (110) are selected corresponding to the position of the first cylinder wall (120), and the first angle of the two to four groups of cooling holes (110) is reduced. The first included angles of other groups of cooling holes (110) distributed along the axial direction of the cylinder (100) are determined according to a preset curve, wherein the preset curve comprises a multi-function curve, a Bezier curve or a spline curve.

Images