Design method of blade height of bearing impeller type radial oil collecting device in aero-engine

Abstract

The application belongs to the technical field of bearing impeller type radial oil collecting device design in an aero-engine, and particularly relates to a bearing impeller type radial oil collecting device blade height design method, which comprises the following steps: making a sliding oil injection line L in the direction of an oil nozzle nozzle; taking the intersection of the sliding oil injection line and the outer wall of the oil collecting ring as a sliding oil movement limit point A; taking a sliding oil movement starting point B on the sliding oil injection line L from the sliding oil movement limit point A in a reverse direction, and the length of the sliding oil movement limit point A and the sliding oil movement starting point B is I, wherein I=V*T; T=60 / (M*N); wherein V is the sliding oil injection speed, m / s; T is the time difference of adjacent blades rotating to the same position, s; M is the number of blades; N is the aero-engine rotating speed, r / min; drawing a circle with the midpoint O of the oil collecting ring as the center and passing through the sliding oil movement starting point B, taking the radius R2 of the circle as the outer radius of the blade; calculating the height h of the blade, h=R2-R1; wherein R1 is the inner radius of the blade.

Description

Technical Field

[0001] This application belongs to the technical field of bearing impeller type radial oil recovery device design in aero-engines, specifically relating to a method for designing the blade height of a bearing impeller type radial oil recovery device in aero-engines. Background Technology

[0002] Bearings in aero engines operate under harsh conditions, especially the main bearings, which require continuous lubrication and cooling.

[0003] With the development of technology, the sliding linear velocity limit of the main bearing in aero-engines has gradually increased. When lubricating and cooling the main bearing by directly injecting lubricating oil, the lubricating oil has difficulty entering the main bearing smoothly under the action of centrifugal force, resulting in low utilization rate of lubricating oil and poor lubrication and cooling effect.

[0004] Currently, to improve the utilization rate of lubricating oil and enhance lubrication and cooling effects, a technical solution has been designed that uses an impeller-type radial oil collection device to supply oil to the main bearing under the ring, such as... Figure 1 As shown, the impeller-type radial oil collection device includes an oil collection ring 1 and multiple blades 2. The oil collection ring 1 has multiple oil collection holes on its sidewall and outer flanges on both sides. The oil collection ring 1 is sleeved on the main shaft 3, forming multiple oil collection grooves between it and the main shaft 3. Each oil collection groove connects to each oil collection hole. The inner ring of the main bearing 4 has multiple circumferentially distributed oil inlet holes on its sidewall. Multiple oil inlet grooves and annular oil collection grooves connect between the inner ring and the main shaft 3, and each oil inlet groove connects to each oil collection groove. The annular oil collection groove connects to each oil inlet hole. Each blade 2... The oil collection chamber is circumferentially connected to the outer side wall of the oil collection ring. Adjacent blades 2 form oil collection cavities, and each oil collection cavity is connected to each oil collection hole. During operation, the oil nozzle 5 sprays lubricating oil obliquely into each oil collection cavity. Under the action of each blade 2, the oil is collected to the center position and then enters the oil collection groove through each oil collection hole. After passing through each oil collection groove and oil inlet groove, the oil enters the annular oil collection groove. Then, under the action of centrifugal force, the oil enters the main bearing 4 through each oil inlet hole to lubricate and cool the main bearing 4. The utilization rate of lubricating oil is high, and a good lubrication and cooling effect can be achieved.

[0005] Practice has shown that the blade height in an impeller-type radial oil recovery device has a significant impact on the utilization rate of lubricating oil. Too high or too low a height will negatively affect the utilization rate of lubricating oil. Currently, when designing an impeller-type radial oil recovery device, the height of blade 2 is often adjusted through trial and error based on the results of oil recovery efficiency tests. This technical approach requires designing and manufacturing various impeller-type radial oil recovery devices with different blade heights for repeated testing. The process is cumbersome, time-consuming, and lacks scientific theoretical guidance, making it difficult to obtain the optimal height of blade 2.

[0006] This application is made in view of the aforementioned technical deficiencies.

[0007] 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

[0008] The purpose of this application is to provide a method for designing the blade height of a bearing impeller-type radial oil recovery device in an aero-engine, so as to overcome or mitigate at least one of the known technical defects.

[0009] The technical solution of this application is:

[0010] A method for designing the blade height of a bearing impeller-type radial oil recovery device in an aero-engine, comprising:

[0011] Draw the oil injection line L with the direction of the fuel injector nozzle;

[0012] The intersection of the lubricating oil injection line and the outer wall of the oil collection ring is taken as the limit point A of the lubricating oil movement;

[0013] On the oil injection line L, take the starting point B of the oil motion in the opposite direction from the oil motion limit point A. The length of the oil motion limit point A and the oil motion starting point B is I, where...

[0014] I = V·T;

[0015] T = 60 / (M·N);

[0016] in,

[0017] V is the lubricating oil injection velocity, m / s;

[0018] T is the time difference, in seconds, between adjacent blades rotating to the same position.

[0019] M represents the number of leaves;

[0020] N represents the engine speed, in r / min;

[0021] Draw a circle with the midpoint O of the oil collection ring as the center and passing through the starting point B of the lubricating oil movement. Take the radius R2 of this circle as the outer radius of the blade.

[0022] Calculate the blade height h = R2 - R1;

[0023] in,

[0024] R1 is the inner radius of the blade.

[0025] According to at least one embodiment of this application, in the above-described method for designing the blade height of a bearing impeller-type radial oil recovery device in an aero-engine, for the main bearing, the aero-engine speed N is taken as the main shaft design speed. Attached Figure Description

[0026] Figure 1 This is a schematic diagram of an impeller-type radial oil collection device supplying oil to the main bearing under the ring, provided in an embodiment of this application.

[0027] Figure 2 This is a schematic diagram of the blade height design method for a bearing impeller-type radial oil recovery device in an aero-engine provided in this application embodiment;

[0028] in:

[0029] 1-Oil recovery ring; 2-Blade; 3-Main shaft; 4-Main bearing; 5-Oil injector.

[0030] 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

[0031] 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.

[0032] 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.

[0033] 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.

[0034] Analysis and practical experience have shown that when the injector 5 obliquely sprays lubricating oil into each oil collection chamber, the closer the lubricating oil is to the root of the leading edge of the next blade 2 before it arrives, the greater the pressure it experiences, resulting in higher oil collection efficiency and higher utilization of the lubricating oil. However, if the lubricating oil reaches the root of the leading edge of the blade 2, it will be ejected and bounced back, reducing the oil collection efficiency and severely affecting the utilization of the lubricating oil. To ensure high utilization of the lubricating oil, the lubricating oil injected into each oil collection chamber by the injector 5 should travel as close as possible to the root of the leading edge of the next blade 2 before it arrives, but not reach the root of the leading edge of the blade 2. Based on this, this application provides a method for designing the blade height of a radial oil collection device for a bearing impeller type in an aero-engine. The following is in conjunction with the attached... Figures 1 to 2 To provide further details.

[0035] Draw the lubricating oil injection line L with the direction of the nozzle 5;

[0036] The intersection of the lubricating oil injection line and the outer wall of the oil collection ring 1 is taken as the limit point A of the lubricating oil movement, which corresponds to the location of the root of the leading edge of the blade 2.

[0037] On the oil injection line L, taking the starting point B of the oil motion in the opposite direction from the oil motion limit point A, corresponding to the position of the leading edge tip of blade 2, the length of the oil motion limit point A and the oil motion starting point B is I, where...

[0038] I = V·T;

[0039] T = 60 / (M·N);

[0040] in,

[0041] V is the oil injection velocity, m / s;

[0042] T is the time difference in seconds between adjacent blades 2 rotating to the same position;

[0043] M represents the number of leaflets 2;

[0044] N represents the engine speed in r / min. For main bearing 4, the design speed of main shaft 3 can be taken.

[0045] Draw a circle with the midpoint O of the oil collection ring 1 as the center and passing through the starting point B of the lubricating oil movement. Take the radius R2 of this circle as the outer radius of the blade 2.

[0046] Calculate the height h of blade 2: h = R2 - R1;

[0047] in,

[0048] R1 is the inner radius of blade 2, which corresponds to the outer radius of oil collection ring 1.

[0049] The calculated h can be used as the applicable height of blade 2, or it can be used as a reference standard for the height of blade 2. Various impeller-type radial oil collection devices with different blade heights can be designed and manufactured for testing. Based on the oil collection efficiency test results, the height of blade 2 can be corrected to find the optimal height with the highest lubrication efficiency and the best lubrication and cooling effect.

[0050] In a specific embodiment, the lubricating oil injection speed V is 25 m / s, the number of blades 2 M is 6, the speed of the aero-engine N is 15000 r / min, the inner radius R1 of the blade 2 is 133 mm, and the time difference T between adjacent blades 2 rotating to the same position is calculated to be 60 / (M·N) = 1 / 1500 s. The length of the lubricating oil motion limit point A and the lubricating oil motion starting point B is I = V·T = 16.7 mm.

[0051] Draw the fuel injector 5 and the oil catcher ring 1 using CAD. Draw the lubricating oil injection line L with the injection direction of the fuel injector 5. Take the starting point B of the lubricating oil movement on the lubricating oil injection line L. The length of the limit point A of the lubricating oil movement and the starting point B of the lubricating oil movement is I = 16.7 mm. Take the midpoint O of the oil catcher ring 1 as the center and the circle passing through the starting point B of the lubricating oil movement. Take the radius R2 = 145 mm of the circle as the outer radius of the blade 2. Calculate the height h of the blade 2 as h = R2 - R1 = 12 mm.

[0052] The blade height design method for the bearing impeller-type radial oil collection device in the above embodiment of the aero-engine is designed by matching the lubricating oil injection speed V, the number of blades 2 N, and the aero-engine speed N. It has a strong principle and can quickly obtain the applicable height of blades 2, which can ensure the utilization rate of lubricating oil and ensure the lubrication and cooling effect without the need for a large number of repetitive tests.

[0053] 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.

[0054] 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 the blade height of a bearing impeller-type radial oil recovery device in an aero-engine, characterized in that, include: Draw the lubricating oil injection line L in the direction of the nozzle (5); Take the intersection of the lubricating oil injection line and the outer wall of the oil collection ring (1) as the limit point A of the lubricating oil movement, which corresponds to the position of the root of the leading edge of the blade (2); On the oil injection line L, take the starting point B of the oil motion in the opposite direction from the oil motion limit point A. This corresponds to the position of the blade tip at the leading edge of blade (2). The length of the oil motion limit point A and the starting point B is I, where... I = V•T; T = 60 / (M•N); in, V is the lubricating oil injection velocity, m / s; T is the time difference, in seconds, between adjacent blades (2) rotating to the same position; M is the number of leaves (2); N represents the engine speed, in r / min; Draw a circle with the midpoint O of the oil collection ring (1) as the center and passing through the starting point B of the lubricating oil movement. Take the radius R2 of this circle as the outer radius of the blade (2). Calculate the height h of the blade (2) = R2 - R1, so that the oil injector (5) injects lubricating oil into each oil collection chamber. Before the next blade (2) arrives, it runs close to the root of the leading edge of the blade (2), but does not reach the root of the leading edge of the blade (2). in, R1 is the inner radius of the blade (2), which corresponds to the outer radius of the oil collection ring (1); For the main bearing (4), the speed N of the aero-engine is taken as the design speed of the main shaft (3).

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