Combustion chamber wall face with locally-encrypted cooling holes and rotational flow combustion chamber

Abstract

The invention provides a combustion chamber wall surface with locally densified cooling holes and a rotational flow combustion chamber. The combustion chamber wall surface comprises a combustion chamber wall surface, a plurality of cooling holes are formed in the wall face of the combustion chamber and distributed according to a temperature distribution curve of the wall face of the combustion chamber. The multiple cooling holes are distributed according to the temperature distribution curve of the wall face of the combustion chamber, the distances between the cooling holes and the adjacent holes are directly related to the local temperature, and the higher the temperature is, the denser the cooling holes are, so that the cooling effect is improved, the wall face temperature is reduced, and generation of local high temperature is avoided.

Description

Technical Field

[0001] The invention relates to the field of combustion chamber structures, and in particular to a combustion chamber wall surface with locally dense cooling holes and a swirl combustion chamber. Background Art

[0002] The combustion chamber wall of a gas turbine is in an extreme high-temperature environment, and only an efficient cooling method can ensure the safety and service life of the combustion chamber. However, advanced combustion methods require a large amount of air to participate in combustion rather than as cooling gas, so how to improve the cooling effect under limited cooling air volume is of great significance. Through searching, it was found that there are inventions related to the divergent cooling wall of the combustion chamber. For example, the invention of patent number CN113217949A proposes a combustion chamber divergent cooling structure and a ramjet combustion chamber, which reduces the required amount of cooling air and improves the engine specific impulse and thrust performance. Patent number CN203769943U discloses engine structural parts and divergent cooling structures. However, these inventions have the following disadvantages: Since the combustion chamber widely uses swirl to stabilize the flame, the swirl impact leads to local high temperature and produces hot spots, making the local cooling effect significantly lower than the design point. The walls mentioned in these inventions all use evenly arranged cooling holes, which cannot solve the problem of local high temperature. Summary of the invention

[0003] In view of the defects in the prior art, an object of the present invention is to provide a combustion chamber wall with locally dense cooling holes and a swirl combustion chamber.

[0004] A combustion chamber wall surface with locally dense cooling holes provided by the present invention comprises: a combustion chamber wall surface;

[0005] A plurality of cooling holes are arranged on the combustion chamber wall, and the cooling holes are distributed according to the temperature distribution curve of the combustion chamber wall:

[0006] The axial positions of the cooling holes in the same row are the same, and the axial distances between the cooling holes in different rows and the adjacent cooling holes are inversely proportional to the average wall temperature near the corresponding row of cooling holes, and satisfy:

[0007] S y,i T w,i α =S y,j T w,j α

[0008] Where i and j represent the i-th and j-th rows of cooling holes, Sy is the average axial distance between the cooling holes and the two adjacent rows of cooling holes, Tw is the average wall temperature of the corresponding row of cooling holes, and α is the axial density coefficient;

[0009] Preferably, the cooling holes are arranged in the transverse direction of the wall surface in such a way that the distance between any cooling hole and the adjacent cooling hole is inversely proportional to the wall surface temperature near the corresponding cooling hole, and satisfies:

[0010] S x,m T w,m β =S x,n T w,n β

[0011] Where m and n represent the mth and nth cooling holes, Sx is the average lateral distance between the cooling holes and the two adjacent rows of cooling holes, Tw is the average wall temperature of the corresponding cooling holes, and β is the lateral density coefficient.

[0012] Preferably, the axial encryption coefficient α and the lateral encryption coefficient β are in the range of 0.5-1.5.

[0013] Preferably, the inclination angle θ of the cooling hole is 20-30°.

[0014] Preferably, the total number of the cooling holes remains unchanged after being distributed according to the temperature distribution curve.

[0015] Preferably, a swirl combustion chamber adopts the combustion chamber wall surface with locally dense cooling holes, comprising: a combustion chamber wall surface, a flame tube, a swirler and a cold air cavity;

[0016] A swirler is installed at one end of the flame tube, and a combustion chamber wall with cooling holes distributed according to a temperature distribution curve is installed in the flame tube. The combustion chamber wall separates the cavity in the flame tube into a cold air cavity.

[0017] Compared with the prior art, the present invention has the following beneficial effects:

[0018] 1. The present application distributes multiple cooling holes according to the temperature distribution curve of the combustion chamber wall. Since the spacing between the cooling holes and adjacent holes is directly related to the local temperature, the higher the temperature, the denser the cooling holes are, which improves the cooling effect and reduces the wall temperature, which is beneficial to avoid the generation of local high temperature.

[0019] 2. This application keeps the total number of cooling holes unchanged, and can adjust the wall temperature without changing the amount of cooling air, thereby preventing local high temperature from occurring. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Other features, objects and advantages of the present invention will become more apparent from the detailed description of non-limiting embodiments made with reference to the following drawings:

[0021] Figure 1 is the cooling hole distribution diagram;

[0022] Figure 2It is a schematic diagram of the swirl combustion chamber structure;

[0023] Figure 3 is the temperature distribution of the wall with uniformly distributed cooling holes calculated by FLUENT;

[0024] Figure 4 It is the wall axial temperature distribution curve;

[0025] Figure 5 is the transverse temperature distribution curve of the wall;

[0026] As shown in the figure:

[0027] DETAILED DESCRIPTION

[0028] The present invention is described in detail below in conjunction with specific embodiments. The following embodiments will help those skilled in the art to further understand the present invention, but are not intended to limit the present invention in any form. It should be noted that, for those of ordinary skill in the art, several changes and improvements can also be made without departing from the concept of the present invention. These all belong to the protection scope of the present invention.

[0029] Example 1

[0030] The purpose of this embodiment is to provide a cooling hole arrangement method suitable for a swirl combustion chamber, which can adaptively adjust the arrangement of cooling holes according to the wall temperature, improve the wall temperature, and prevent the generation of hot spots.

[0031] like Figure 2 As shown, this embodiment includes: a combustion chamber wall 1, a flame tube 2, a swirler 3 and a cold air cavity 4; the swirler 3 is installed at one end of the flame tube 2, and the flame tube 2 is installed with a combustion chamber wall 1 with cooling holes distributed according to a temperature distribution curve, and the combustion chamber wall 1 separates the cavity in the flame tube 2 into a cold air cavity 4.

[0032] like Figure 1 As shown, a plurality of cooling holes are arranged on the combustion chamber wall 1, and the plurality of cooling holes are distributed according to the temperature distribution curve of the combustion chamber wall 1:

[0033] The axial positions of the cooling holes in the same row are the same, and the axial distances between the cooling holes in different rows and the adjacent cooling holes are inversely proportional to the average wall temperature near the corresponding row of cooling holes, and satisfy:

[0034] S y,i T w,i α =S y,j T w,j α

[0035] Where i and j represent the i-th row along the flow direction ( Figure 1 Sy is the average axial distance between the cooling holes and the two adjacent rows of cooling holes, Tw is the average wall temperature of the corresponding row of cooling holes, and α is the axial density coefficient.

[0036] The wall along the horizontal direction ( Figure 1 The arrangement of cooling holes (rows) is that the distance between any cooling hole and the adjacent cooling hole is inversely proportional to the wall temperature near the corresponding cooling hole, and satisfies:

[0037] S x,m T w,m β =S x,n T w,n β

[0038] Where m and n represent the mth and nth cooling holes, Sx is the average lateral distance between the cooling holes and the two adjacent rows of cooling holes, Tw is the average wall temperature of the corresponding cooling holes, and β is the lateral density coefficient.

[0039] In one embodiment, the axial density coefficient α and the lateral density coefficient β are in the range of 0.5-1.5.

[0040] In one embodiment, the inclination angle θ of the cooling hole is 20-30°.

[0041] In one embodiment, the total number of cooling holes distributed according to the temperature distribution curve remains unchanged.

[0042] Example 2

[0043] Example 2 is a preferred example of Example 1.

[0044] like Figure 1 As shown, this embodiment can be implemented through the following technical solutions: a uniformly distributed combustion chamber wall 1 cooling structure is established through UG, and the temperature distribution of the combustion chamber wall 1 is calculated through FLUENT, the mainstream is a high-temperature combustion gas of 1800K, and the cooling air is a low-temperature air of 300K. According to the calculated wall temperature, the arrangement of the divergent cooling holes of the combustion chamber wall 1 is adjusted. Specifically, for different rows of cooling holes distributed axially, the average axial spacing between each row of holes and the adjacent rows of holes is inversely proportional to the average temperature of the wall of the row of cooling holes. For the same row of holes, the lateral spacing between a single cooling hole and the adjacent cooling holes is inversely proportional to the average temperature of the wall of the cooling hole, and the total number of cooling holes remains unchanged. The degree of arrangement of the cooling holes is adjusted by the axial density coefficient and the lateral density coefficient.

[0045] like Figure 3 As shown, the temperature distribution of the wall with uniformly distributed cooling holes obtained by FLUENT calculation.

[0046] The average axial distance between different rows of cooling holes and their adjacent rows of holes satisfies the relationship:

[0047] S y,i T w,i α =S y,j T w,j α

[0048] This formula is for a row of cooling holes. In the formula, i and j represent the i-th and j-th rows of cooling holes, Sy is the average axial distance between the cooling hole and the two adjacent rows of cooling holes, Tw is the average wall temperature of the row of cooling holes, and α is the axial density coefficient, which can adjust the degree of cooling hole density. The higher the average wall temperature, the smaller the axial distance, and the denser the cooling holes.

[0049] The average lateral distance between a single cooling hole and its adjacent holes satisfies the relationship:

[0050] S x,m T w,m β =S x,n T w,n β

[0051] This formula is for a single cooling hole. In the formula, m and n represent the mth and nth cooling holes, Sx is the average lateral distance between the cooling hole and the two adjacent rows of cooling holes, Tw is the average wall temperature of the cooling hole, and β is the lateral density coefficient, which can adjust the degree of cooling hole density. The higher the wall temperature, the smaller the lateral distance, and the denser the cooling holes.

[0052] In one embodiment, the axial density coefficient α and the lateral density coefficient β are in the range of 0.5-1.5.

[0053] In one implementation, the cooling hole arrangement method of this embodiment is compared with the original method, and the total number of cooling holes remains unchanged.

[0054] Figure 4 For the optimized wall axial temperature distribution, the axial density index α ranges from 0.5 to 1.5. As the axial density index α increases, the maximum temperature of the wall gradually decreases. Figure 5 For the optimized lateral temperature distribution of the wall, the lateral density index β ranges from 0.5 to 1.5. As β increases, the lateral distribution of the wall temperature tends to be uniform. The overall effect of the wall temperature after density is basically the same, and the maximum temperature is significantly reduced. This method can avoid the generation of local high temperature and eliminate hot spots under the premise that the overall cooling performance is not much different.

[0055] In the description of the present application, it should be understood that the terms "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0056] The above describes the specific embodiments of the present invention. It should be understood that the present invention is not limited to the above specific embodiments, and those skilled in the art can make various changes or modifications within the scope of the claims, which does not affect the essence of the present invention. In the absence of conflict, the embodiments of the present application and the features in the embodiments can be combined with each other arbitrarily.

Claims

1. A combustion chamber wall with locally dense cooling holes, characterized in that: include: Combustion chamber wall (1); A plurality of cooling holes are arranged on the combustion chamber wall surface (1), and the plurality of cooling holes are distributed according to a temperature distribution curve of the combustion chamber wall surface (1): The axial positions of the cooling holes in the same row are the same, and the axial distances between the cooling holes in different rows and the adjacent cooling holes are inversely proportional to the average wall temperature near the corresponding row of cooling holes, and satisfy: S y,i T w,i α =S y,j T w,j α Where i and j represent the i-th and j-th rows of cooling holes along the flow direction, Sy is the average axial distance between the cooling holes and the two adjacent rows of cooling holes, Tw is the average wall temperature of the corresponding row of cooling holes, and α is the axial density coefficient.

2. The combustion chamber wall with locally dense cooling holes according to claim 1, characterized in that: The arrangement of cooling holes along the wall in the transverse direction is that the distance between any cooling hole and the adjacent cooling hole is inversely proportional to the wall temperature near the corresponding cooling hole, and satisfies: S x,m T w,m β =S x,n T w,n β Where m and n represent the mth and nth cooling holes, Sx is the average lateral distance between the cooling holes and the two adjacent rows of cooling holes, Tw is the average wall temperature of the corresponding cooling holes, and β is the lateral density coefficient.

3. The combustion chamber wall with locally dense cooling holes according to claim 2, characterized in that: The range of the axial density coefficient α and the lateral density coefficient β is 0.5-1.

5.

4. The combustion chamber wall with locally dense cooling holes according to claim 1, characterized in that: The inclination angle θ of the cooling hole is 20-30°.

5. The combustion chamber wall with locally dense cooling holes according to claim 1, characterized in that: The total number of the cooling holes after being distributed according to the temperature distribution curve remains unchanged.

6. A swirl combustion chamber, characterized in that: A combustion chamber wall surface with locally dense cooling holes according to any one of claims 1 to 5.

7. The swirl combustion chamber according to claim 6, characterized in that: include: Combustion chamber wall (1), flame tube (2), swirler (3) and cold air cavity (4); A swirler (3) is installed at one end of the flame tube (2), and a combustion chamber wall (1) with cooling holes distributed according to a temperature distribution curve is installed in the flame tube (2). The combustion chamber wall (1) separates the cavity in the flame tube (2) into a cold air cavity (4).

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