Method for designing a subsonic rotor blade of an engine fan and compressor handling casing

Abstract

The application belongs to the technical field of engine fan and compressor processing machine casing subsonic rotor blade design, and particularly relates to an engine fan and compressor processing machine casing subsonic rotor blade design method. The design is designed without a processing machine casing at a design rotating speed, and a shock wave form at a transonic rotor blade tip is designed as a near stall point form. On this basis, the design adopts a processing machine casing, and at the design rotating speed, the shock wave form at the transonic rotor blade tip is degraded from the near stall point form to a near highest efficiency point form, so as to ensure the efficiency of the fan and the compressor in the engine at the design rotating speed and avoid the efficiency decline caused by the adoption of the processing machine casing.

Description

Technical Field

[0001] This application belongs to the technical field of transonic rotor blade design for engine fans and compressor handling casings, specifically relating to a design method for transonic rotor blades under engine fans and compressor handling casings. Background Technology

[0002] In engines, to improve the anti-stall capability of the transonic rotor blade tips of the fan and compressor and increase surge margin, a treatment casing is often designed for the fan and compressor. Based on the type of treatment slot, treatment casings include circumferential slot type, inclined groove type, circular arc inclined groove type, and zigzag slot type. A circumferential slot type treatment casing is as follows: Figure 1 As shown, the inclined groove type processing casing is as follows Figure 2 As described above, the arc-shaped inclined groove type processing casing, such as Figure 3 As shown, the zigzag-seam type processing casing is as follows Figure 4 As shown, the zigzag-slotted casing is particularly effective in improving the surge margin of fan and compressor rotor blades at low and medium speeds, and is widely used in engineering practice.

[0003] Typical shock waves in supersonic blade cascades exhibit clogging point morphology, back pressure increase morphology, near-maximum efficiency point morphology, and near-stall point morphology, such as... Figure 5 As shown, in order to balance efficiency and surge margin, it is generally desirable that the shock wave morphology at the tip of the transonic rotor blades of the fan and compressor be either a back pressure increase morphology or a morphology close to the point of maximum efficiency.

[0004] Currently, when designing fans and compressors, the shock wave morphology at the transonic rotor blade tip is often designed to be either a back pressure increase morphology or a near-maximum efficiency morphology at the design speed. Under this technical approach, the use of a casing will affect the shock wave morphology at the transonic rotor blade tip at the design speed. If it was previously a near-maximum efficiency morphology, it is prone to degenerate into a back pressure increase morphology; if it was previously a back pressure increase morphology, it is prone to degenerate into a blockage point morphology, causing the fan and compressor to have lower-than-expected efficiency at the design speed.

[0005] This application is made in view of the aforementioned technical deficiencies.

[0006] It should be noted that the above background information is only used to assist in understanding the inventive concept and technical solution of this invention, and it does not necessarily belong to the prior art of this application. In the absence of clear evidence that the above information was disclosed on the filing date of this application, the above background information should not be used to evaluate the novelty and inventiveness of this application. Summary of the Invention

[0007] The purpose of this application is to provide a design method for a transonic rotor blade handling casing for an engine fan and compressor, so as to overcome or mitigate at least one of the known technical defects.

[0008] The technical solution of this application is:

[0009] A method for designing transonic rotor blades under an engine fan and compressor handling casing, comprising:

[0010] At the design speed, without a processing casing, the shock wave shape at the tip of the transonic rotor blade is designed to be near the stall point.

[0011] According to at least one embodiment of this application, in the above-described design method for the transonic rotor blades of the engine fan and compressor handling casing, the handling casing adopts a zigzag-slotted handling casing.

[0012] This application has at least the following beneficial technical effects:

[0013] A method for designing transonic rotor blades under the treatment casing of an engine fan and compressor is provided. The design, without the treatment casing, at the design speed, aims to make the shock wave morphology at the tip of the transonic rotor blades into a near-stall morphology. Based on this, a treatment casing is designed, and at the design speed, the shock wave morphology at the tip of the transonic rotor blades degenerates from a near-stall morphology to a near-maximum efficiency morphology. This ensures the efficiency of the fan and compressor in the engine at the design speed and avoids the efficiency reduction caused by the use of the treatment casing. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of a circumferential slotted processing casing;

[0015] Figure 2 This is a schematic diagram of a sloping groove type processing casing;

[0016] Figure 3 This is a schematic diagram of a circular arc inclined slot type processing casing;

[0017] Figure 4 This is a schematic diagram of a zigzag-seam type processing casing;

[0018] Figure 5 This is a schematic diagram of the shock wave morphology development in a supersonic blade cascade.

[0019] Figure 6 This is a schematic diagram comparing the shock wave morphology at the tips of the transonic rotor blades before and after the processing casing, using the engine fan and compressor transonic rotor blade processing casing design method provided in the embodiments of this application.

[0020] To better illustrate this embodiment, some parts in the accompanying drawings may be omitted, enlarged, or reduced, and do not represent the actual product dimensions. Furthermore, the drawings are for illustrative purposes only and should not be construed as limiting this application. Detailed Implementation

[0021] To make the technical solution and advantages of this application clearer, the technical solution of this application will be described in a clearer and more complete manner below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are only some embodiments of this application, and are only used to explain this application, not to limit this application. It should be noted that, for ease of description, only the parts related to this application are shown in the accompanying drawings. Other related parts can be referred to the general design. In the absence of conflict, the embodiments and technical features in the embodiments of this application can be combined with each other to obtain new embodiments.

[0022] Furthermore, unless otherwise defined, the technical or scientific terms used in this application description shall have the ordinary meaning understood by one of ordinary skill in the art to which this application pertains. The terms "upper," "lower," "left," "right," "center," "vertical," "horizontal," "inner," and "outer," etc., used in this application description to indicate relative direction or positional relationship are used only to indicate relative orientation or positional relationship, and do not imply that the device or component must have a specific orientation, or be constructed and operated in a specific orientation. When the absolute position of the described object changes, its relative positional relationship may also change accordingly, and therefore should not be construed as a limitation on this application. The terms "first," "second," "third," and similar terms used in this application description are used only for descriptive purposes to distinguish different components, and should not be construed as indicating or implying relative importance. The terms "a," "one," or "the," etc., used in this application description should not be construed as an absolute limitation on quantity, but should be construed as indicating the existence of at least one. The terms "including," "comprising," etc., used in this application description mean that the element or object preceding the word covers the element or object listed after the word and its equivalents, without excluding other elements or objects.

[0023] Furthermore, it should be noted that, unless otherwise explicitly specified and limited, terms such as “installation,” “connection,” and “linkage” used in the description of this application should be interpreted broadly. For example, a connection can be a fixed connection, a detachable connection, or an integral 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; or it can be a connection within two components. Those skilled in the art can understand its specific meaning in this application according to the specific circumstances.

[0024] The following is in conjunction with the appendix Figures 1 to 6 This application will be described in further detail.

[0025] A method for designing transonic rotor blades under an engine fan and compressor handling casing, comprising:

[0026] At the design speed, without a processing casing, the shock wave shape at the tip of the transonic rotor blade is designed to be near the stall point.

[0027] Regarding the transonic rotor blade design method for the engine fan and compressor treatment casing disclosed in the above embodiments, those skilled in the art will understand that, at the design speed without a treatment casing, the shock wave morphology at the tip of the transonic rotor blade is designed as a near-stall point morphology. Based on this, a treatment casing is designed, and at the design speed, the shock wave morphology at the tip of the transonic rotor blade will degenerate from a near-stall point morphology to a near-maximum efficiency point morphology. This can ensure the efficiency of the fan and compressor in the engine at the design speed and avoid the efficiency reduction caused by the use of a treatment casing. It is an integrated design method of transonic rotor blades and treatment casing.

[0028] Regarding the transonic rotor blade design method for the engine fan and compressor treatment casing disclosed in the above embodiments, those skilled in the art can understand that, in order to ensure that, after adopting the treatment casing, the shock wave morphology at the tip of the transonic rotor blade degenerates from the near-stall point morphology to the near-maximum efficiency point morphology at the design speed, the shock wave morphology at the tip of the transonic rotor blade can be designed as a near-stall point morphology with a small margin without the treatment casing at the design speed.

[0029] According to at least one embodiment of this application, in the above-described design method for the transonic rotor blades of the engine fan and compressor handling casing, the handling casing adopts a zigzag-slotted handling casing.

[0030] In one specific embodiment, according to the aforementioned design method for transonic rotor blades under the engine fan and compressor treatment casing, at the design speed, without a treatment casing, the shock wave morphology at the transonic rotor blade tip is designed as a near-stall point morphology, and a zigzag-slotted treatment casing is designed. A comparison of the shock wave morphologies at the transonic rotor blade tips before and after the zigzag-slotted treatment casing design is provided. Figure 6 As shown, compared with the unprocessor casing, the design of the zigzag-slotted processor casing increases the efficiency of the low-pressure compressor at the design speed, enabling the efficiency at the design speed to reach the expected target, and the performance of the compressor at low speed also reaches the expected target.

[0031] The various embodiments in the specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other.

[0032] The technical solution of this application has been described in conjunction with the preferred embodiments shown in the accompanying drawings. Those skilled in the art should understand that the scope of protection of this application is obviously not limited to these specific embodiments. Without departing from the principles of this application, those skilled in the art can make equivalent changes or substitutions to the relevant technical features, and the technical solutions after these changes or substitutions will all fall within the scope of protection of this application.

Claims

1. A method for designing transonic rotor blades under an engine fan and compressor casing, characterized in that, include: At the design speed, without a processing casing, the shock wave morphology at the tip of the transonic rotor blades is designed to be near the stall point morphology. Based on this, the design adopts a processing casing, and at the design speed, the shock wave morphology at the tip of the transonic rotor blade degenerates from the near stall point morphology to the near maximum efficiency point morphology. The processing casing adopts a zigzag-seam type processing casing.

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