A method for adjusting the uniformity of the internal flow field of an air compressor

Abstract

This invention provides a method for adjusting the uniformity of the internal flow field of an air compressor. Addressing the influence of the stator blade installation angle on flow field uniformity, this invention proposes a method for calculating the influence coefficient: measuring the installation angle of each blade sequentially to generate installation angle data. If the influence coefficient does not meet the standard, the entire stage of blades needs to be reassembled, and the blade installation angle positions rearranged according to their respective installation angles to reduce the influence coefficient. The method uses programming to optimize the blade installation angle arrangement with the goal of reducing the influence coefficient. Advantages of this invention: The method for adjusting the uniformity of the internal flow field of an air compressor described in this invention, by adjusting the stator blade installation position and improving the blade installation angle distribution, can effectively reduce the influence of the blade installation angle on the flow field uniformity, solve the problem of insufficient compressor stability margin, and improve engine reliability.

Description

Technical Field

[0001] This invention relates to the field of aero-engine technology, and in particular to a method for adjusting the uniformity of the internal flow field of an air compressor. Background Technology

[0002] The stator blades of an aero-engine compressor are primarily used to alter the airflow angle within the component, ensuring the airflow direction meets downstream requirements. The ability of the compressor stator blades to change the airflow angle is mainly determined by their installation angle. Significant deviations in the installation angle of the entire stage of blades disrupt the uniformity of the internal flow field, thereby reducing the compressor's stable operating margin. Therefore, strict control of the installation angle of the entire stage of blades is necessary during engine manufacturing and assembly. In actual manufacturing, relying on design experience and reliability analysis results, upper and lower tolerances for the blade installation angle are provided, controlling the installation angle of the entire stage of blades within these tolerances. However, methods for adjusting the uniformity of the internal flow field of the compressor are lacking. Summary of the Invention

[0003] The purpose of this invention is to improve the uniformity of the internal flow field of the compressor by adjusting the installation angle distribution of the stator blades, and a method for adjusting the uniformity of the internal flow field of the compressor is provided.

[0004] This invention provides a method for adjusting the uniformity of the internal flow field of an air compressor. The method is characterized by: during engine manufacturing and assembly, measuring the installation angle of the entire stage blades; determining whether the installation angle θ meets the upper and lower tolerances of the blade installation angle to decide whether the blades need to be replaced or reassembled. When the installation angle meets the tolerance range, the blade installation position will not be adjusted.

[0005] A compressor stage consists of 30 to 110 stator blades. Each stator blade has a different installation angle. When the installation angles of two blades differ significantly, the airflow passage between them will exhibit considerable variability, resulting in significant non-uniformity of the internal flow field of the compressor at that location.

[0006] To address the impact of the entire stage blade installation angle on flow field non-uniformity, a method for calculating the influence coefficient is proposed:

[0007] The installation angle of each blade is measured in the order of blade installation to form installation angle data.

[0008] The influence coefficient R is calculated using the following formula:

[0009]

[0010] Where θ i (i = 1, 2... N) represents the installation angle of the i-th blade, N is the number of blades in the entire stage, ES is the upper tolerance of the installation angle of this blade, and EI is the lower tolerance of the installation angle of this blade. In the calculation, θ...N+1 =θ1.

[0011] The influence coefficient R should satisfy R≤0.3. A reasonable influence coefficient standard should be set based on the actual structure of the product and engineering experience.

[0012] If the influence coefficient standard is not met, the entire stage of blades needs to be reassembled, and the blade installation angle positions should be rearranged according to the blade installation angle to reduce the influence coefficient.

[0013] Using programming, the blade installation angles were optimized to reduce the impact coefficient. The following optimized arrangement was adopted:

[0014] Arrange the blades one position at a time in a clockwise direction, from largest to smallest, according to the blade installation angle value.

[0015] The blades are divided into three groups according to their installation angle from largest to smallest, and each group is arranged one position apart in a clockwise direction.

[0016] The blades are divided into four groups according to their installation angle from largest to smallest, and each group is arranged one position apart in a clockwise direction.

[0017] This application proposes a method for calculating the influence coefficient of stator blade installation angle distribution on the uniformity of the internal flow field of a compressor. By calculating this influence coefficient, the uniformity of the internal flow field is evaluated. A method for adjusting the stator blade installation angle distribution is also proposed.

[0018] Compared with the prior art, the advantages of this invention are:

[0019] The compressor internal flow field uniformity adjustment method described in this invention improves the blade installation angle distribution by adjusting the stator blade installation position, which can effectively reduce the impact of blade installation angle on flow field uniformity, solve the problem of insufficient compressor stability margin, and improve engine reliability. Attached Figure Description

[0020] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments:

[0021] Figure 1 Schematic diagram of blade mounting angle measurement principle;

[0022] Figure 2 Schematic diagram of the entire stage blade installation angle;

[0023] Figure 3 Schematic diagram of common blade mounting angles;

[0024] Figure 1 In the diagram, A represents the leading edge of the blade, B represents the trailing edge of the blade, C represents the probe of the device, S represents the blade to be measured, and θ represents the blade installation angle. Detailed Implementation

[0025] The present invention will be further explained below with reference to specific implementation schemes, but it is not limited to the present invention. The structures, proportions, sizes, etc. shown in the accompanying drawings are only used to complement the content disclosed in the specification, so as to enable those skilled in the art to understand and read, and are not intended to limit the conditions under which the present invention can be implemented. Therefore, they have no substantial technical significance. Any modification of the structure, change of the proportion relationship or adjustment of the size, without affecting the effect and purpose that the present invention can produce, should still fall within the scope of the technical content disclosed in the present invention.

[0026] During engine manufacturing and assembly, it is necessary to measure the installation angle of the entire stage blades. The main angle measurement principle is described in [link to article]. Figure 1 By determining whether the installation angle θ meets the upper and lower tolerances of the blade installation angle, it is decided whether the blade needs to be replaced or reassembled. When the installation angle meets the tolerance range, the blade installation position will not be adjusted.

[0027] The compressor stage stator blades consist of 30 to 110 stator blades. Each stator blade has a different installation angle, see [link to documentation]. Figure 2 When the installation angles of the two blades differ significantly, the airflow passage in between will exhibit considerable variability, resulting in significant non-uniformity in the internal flow field of the compressor at that location.

[0028] Considering the influence of the entire stage blade installation angle on flow field non-uniformity, a method for calculating the influence coefficient is proposed:

[0029] The installation angle of each blade is measured in the order of blade installation to form installation angle data.

[0030] The influence coefficient R is calculated using the following formula:

[0031]

[0032] Where θ i (i = 1, 2... N) represents the installation angle of the i-th blade, N is the number of blades in the entire stage, ES is the upper tolerance of the installation angle of this blade, and EI is the lower tolerance of the installation angle of this blade. In the calculation, θ... N+1 =θ1.

[0033] The influence coefficient R should satisfy R≤0.3. A reasonable influence coefficient standard should be set based on the actual structure of the product and engineering experience.

[0034] If the influence coefficient standard is not met, the entire stage of blades needs to be reassembled, and the blade installation angle positions should be rearranged according to the blade installation angle to reduce the influence coefficient.

[0035] Using programming, the blade installation angle is optimized to reduce the impact coefficient. The following optimization methods are available; see details below. Figure 3 :

[0036] Arrange the blades one position at a time in a clockwise direction, from largest to smallest, according to the blade installation angle value.

[0037] The blades are divided into three groups according to their installation angle from largest to smallest, and each group is arranged one position apart in a clockwise direction.

[0038] The blades are divided into four groups according to their installation angle from largest to smallest, and each group is arranged one position apart in a clockwise direction.

[0039] Matters not covered in this invention are common knowledge.

[0040] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A method for adjusting the uniformity of the internal flow field of an air compressor, characterized in that: The compressor stage stator blades consist of 30 to 110 stator blades, each with a different installation angle. When the installation angles of two blades differ significantly, the airflow passage in the middle will exhibit a high degree of variability, resulting in a significant non-uniformity of the internal flow field of the compressor at that location. To address the impact of the entire stage blade installation angle on flow field non-uniformity, a method for calculating the influence coefficient is proposed: Measure the installation angle of each blade in the order of blade installation to form installation angle data; The influence coefficient R is calculated using the following formula: Where θ i (i = 1, 2... N) represents the installation angle of the i-th blade, N is the number of blades in the entire stage, ES is the upper tolerance of the installation angle of this blade, and EI is the lower tolerance of the installation angle of this blade; during calculation, θ N+1 =θ1; The influence coefficient R should satisfy R≤0.3; a reasonable influence coefficient standard should be set according to the actual structure of the product and engineering experience. If the influence coefficient standard is not met, the entire stage of blades needs to be reassembled, and the blade installation angle positions should be rearranged according to the blade installation angle to reduce the influence coefficient.

2. The method for adjusting the uniformity of the internal flow field of a compressor according to claim 1, characterized in that: Using programming, the blade installation angle was optimized to reduce the impact coefficient; the following optimization arrangement was adopted: Arrange the blades one position apart in a clockwise direction, from largest to smallest, according to the blade installation angle value; Based on the blade installation angle values ​​from large to small, they are divided into three groups, and each group is arranged one position apart in a clockwise direction. The blades are divided into four groups according to their installation angle from largest to smallest, and each group is arranged one position apart in a clockwise direction.

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