Shunt Ring-Type Line Design Method

Abstract

The present invention relates to a design method for a split-ring type line, which includes: obtaining an initial flow path WON of the engine fan booster stage through S2 flow-through design; selecting a split-ring type line design area BOC section in the initial flow path WON; establishing a coordinate system OXY with the split point 0 of the split-ring type line design area BOC section as the origin; obtaining according to the coordinate system OXY: the coordinates of point O (0, 0), the coordinates of point B, the slope of point B, the coordinates of point C, the slope of point C; establishing an elliptic equation for the upper part OB section of the split ring in the coordinate system OXY, and solving to obtain the type line of the OB section; establishing an elliptic equation for the lower part OC section of the split ring in the coordinate system OXY, and solving to obtain the type line of the OC section; combining the type line of the upper part OB section of the split ring and the type line of the lower part OC section of the split ring to form a complete split-ring type line. The present invention can optimize the split-ring type line.

Description

Technical Field

[0001] The present invention relates to the field of aerospace technology, and in particular to a design method for a splitter ring profile. Background Art

[0002] The twin-duct turbofan engine is an important form of aeroengine. The splitter ring is a distribution structure that enables air to enter the core duct and the bypass duct respectively, and is also an important component that affects the air flow distribution into the core and bypass ducts of the engine under different operating conditions. After the air flow passes through the fan, it impacts the splitter ring at a certain speed and angle, forming a stagnation point (where the air flow velocity is 0, also known as the split duct point) at the front end of the splitter ring. A part of the air flow enters the bypass duct, and the other part enters the core duct. The front-end shape, axial, and radial positions of the splitter ring have a great influence on the air flow distribution and the local flow field, thus affecting the operating conditions and performance level of the twin-duct turbofan engine.

[0003] When the shape, axial, and radial positions of the splitter ring are inappropriate, the air flow will impact the leading edge of the splitter ring at an unexpected angle, resulting in the non-meeting of the overall engine requirements for the core and bypass air flows. At the same time, unhealthy flow fields such as vortices formed locally in the splitter ring directly deteriorate the operating state of the fan booster stage and reduce its stable operating ability and range. Summary of the Invention

[0004] Some embodiments of the present invention propose a design method for a splitter ring profile, which can optimize the splitter ring profile.

[0005] Some embodiments of the present invention provide a design method for a splitter ring profile, which includes:

[0006] Obtaining the initial flow path WON of the engine fan booster stage through S2 through-flow design;

[0007] Selecting the BOC section of the splitter ring profile design area in the initial flow path WON;

[0008] Establishing a coordinate system OXY with the split duct point 0 of the BOC section of the splitter ring profile design area as the origin;

[0009] Obtaining according to the coordinate system OXY: the coordinates of point O (0, 0), the coordinates of point B The slope of point B The coordinates of point C The slope of point C

[0010] Establishing an ellipse equation for the upper OB section of the splitter ring in the coordinate system OXY, and solving to obtain the OB section profile;

[0011] Establishing an ellipse equation for the lower OC section of the splitter ring in the coordinate system OXY, and solving to obtain the OC section profile;

[0012] Combine the upper OB section profile line and the lower OC section profile line of the shunt ring to form a complete shunt ring profile line.

[0013] In some embodiments, the shunt ring profile line design method further includes: performing numerical simulation calculations on the combined complete shunt ring profile line, and adjusting the complete shunt ring profile line according to the numerical simulation calculation results and design requirements.

[0014] In some embodiments, establishing the ellipse equation of the upper OB section of the shunt ring in the coordinate system OXY, and the method for obtaining the OB section profile line includes:

[0015] According to the ellipse equation The coordinates of point B And the slope of point B Obtain the following system of equations;

[0016]

[0017] Solve for a1 and b1 to obtain the OB section profile line equation

[0018] In some embodiments, establishing the ellipse equation of the lower OC section of the shunt ring in the coordinate system OXY, and the method for obtaining the OC section profile line includes:

[0019] According to the ellipse equation The coordinates of point C And the slope of point C Obtain the following system of equations;

[0020]

[0021] Solve for a2 and b2 to obtain the OC section profile line equation 0.

[0022] In some embodiments, the method for adjusting the complete shunt ring profile line includes: offsetting the shunt point 0 radially and / or axially, constructing a transformed coordinate system O′X′Y′, and re-obtaining the complete shunt ring profile line according to the transformed coordinate system O′X′Y′.

[0023] In some embodiments, the method for re-obtaining the complete shunt ring profile line includes:

[0024] Transform the coordinates of point B, the slope of point B, the coordinates of point C, and the slope of point C into the coordinate system O′X′Y′;

[0025] Re-establish the ellipse equation of the upper O′B section of the shunt ring in the coordinate system O′X′Y′, and solve to obtain the O′B section profile line;

[0026] Re - establish the elliptic equation of the lower part O′C of the shunt ring in the coordinate system O′X′Y′, and solve to obtain the profile line of the O′C section;

[0027] Combine the newly obtained profile line of the upper part O′B of the shunt ring and the profile line of the lower part O′C of the shunt ring to form a new complete shunt ring profile line.

[0028] Based on the above - mentioned technical solution, the present invention has at least the following beneficial effects:

[0029] In some embodiments, a coordinate system is established with the sub - culvert point as the origin, the initial shunt ring profile line is divided into upper and lower segments, and solution equations are respectively established to realize the non - symmetric elliptical profile line at the front end of the shunt ring profile line, and ensure the first - order smooth continuity at the connection with the inner and outer culvert flow paths. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] The drawings described herein are used to provide a further understanding of the present invention, and constitute a part of this application. The schematic embodiments of the present invention and their descriptions are used to explain the present invention, and do not constitute an improper limitation of the present invention. In the drawings:

[0031] Figure 1 It is a schematic diagram of establishing a coordinate system OXY with the sub - culvert point 0 of the BOC section of the shunt ring profile line design area as the origin according to some embodiments of the present invention;

[0032] Figures 2 to 4 They are all schematic diagrams of the adjustment of the shunt ring profile line according to some embodiments of the present invention;

[0033] Figure 5 It is a schematic flow chart of the shunt ring profile line design method according to some embodiments of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0034] Next, the technical solutions in the embodiments will be clearly and completely described in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0035] In the description of the present invention, it should be understood that the orientation or positional relationship indicated by the terms "center", "longitudinal", "transverse", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus cannot be understood as a limitation on the protection scope of the present invention.

[0036] The dual-ducted turbofan engine includes a splitter ring. The splitter ring is used to make the air flow enter the core duct and the bypass duct of the engine respectively, and can also adjust the air flow rate entering the core duct and the bypass duct according to different working states of the engine.

[0037] As Figure 1 shown, after the air flow passes through the fan of the engine, it impacts the splitter ring at a certain speed and angle, forming a stagnation point (where the air flow speed is 0, also known as the split-duct point) at the front end of the splitter ring. Part of the air flow enters the bypass duct, and the other part enters the core duct.

[0038] When the shape, axial position, and radial position of the splitter ring are inappropriate, the air flow will impact the leading edge of the splitter ring at an unexpected angle, resulting in the flow rates in the core duct and the bypass duct not meeting the requirements of the whole engine. At the same time, unhealthy flow fields such as vortices are formed locally on the splitter ring, directly causing the working state of the fan booster stage to deteriorate and reducing its stable working ability and range.

[0039] Based on the influence of the front shape, axial position, and radial position of the splitter ring on the air flow distribution and local flow field, some embodiments of the present disclosure provide a splitter ring profile design method for optimizing the local flow process, meeting the requirements of the overall engine bypass ratio, and improving the performance of the fan booster stage.

[0040] In some embodiments, as Figure 5 shown, the splitter ring profile design method includes:

[0041] Obtain the initial flow path WON of the engine fan booster stage through S2 through-flow design;

[0042] Select the BOC section of the splitter ring profile design area in the initial flow path WON;

[0043] Establish a coordinate system OXY with the split-duct point 0 of the BOC section of the splitter ring profile design area as the origin, as Figure 1 shown;

[0044] Obtain according to the coordinate system OXY: the coordinates of point O (0, 0), the coordinates of point B the slope of point B the coordinates of point C the slope of point C

[0045] Establish an ellipse equation for the upper OB section of the splitter ring in the coordinate system OXY, and solve to obtain the profile of the OB section;

[0046] Establish an ellipse equation for the lower OC section of the splitter ring in the coordinate system OXY, and solve to obtain the profile of the OC section;

[0047] Combine the profile of the upper OB section of the splitter ring and the profile of the lower OC section of the splitter ring to form a complete splitter ring profile.

[0048] The S2 flow-through design is a typical method for the aerodynamic design of the fan booster stage and the high-pressure compressor of an aeroengine.

[0049] In the above embodiments, a coordinate system is established with the split flow point as the origin, the initial split flow ring line is divided into upper and lower sections, and solution equations are established respectively to realize the non-symmetric elliptical line shaping at the front end of the split flow ring line, so that the split flow ring obtains a better local flow field under different working conditions, and the slopes at the connection points are equal, ensuring first-order smooth continuity at the connection with the inner and outer flow paths. The smoothness of the flow path profile is beneficial to reducing flow losses.

[0050] In some embodiments, the split flow ring line design method further includes: performing numerical simulation calculations on the complete split flow ring line formed by combination, and adjusting the complete split flow ring line according to the numerical simulation calculation results and design requirements.

[0051] Optionally, perform numerical simulation calculations on the fan booster stage scheme of the split flow ring line, analyze the details of the local flow field of the split flow ring, and adjust the split flow ring line as needed according to design experience and design specification requirements until the design requirements are met.

[0052] In some embodiments, establishing the elliptical equation of the upper OB section of the split flow ring in the coordinate system OXY, the method for obtaining the OB section line includes:

[0053] According to the elliptical equation The coordinates of point B And the slope of point B The following system of equations is obtained;

[0054]

[0055] Solve for a1 and b1 to obtain the OB section line equation

[0056] In some embodiments, establishing the elliptical equation of the lower OC section of the split flow ring in the coordinate system OXY, the method for obtaining the OC section line includes:

[0057] According to the elliptical equation The coordinates of point C And the slope of point C The following system of equations is obtained;

[0058]

[0059] Solve for a2 and b2 to obtain the OC section line equation

[0060] In some embodiments, the method for adjusting the complete split-ring type line includes: offsetting the split point 0 radially and / or axially, constructing a transformed coordinate system O′X′Y′, and re-obtaining the complete split-ring type line according to the transformed coordinate system O′X′Y′.

[0061] In some embodiments, the split-ring type line design method includes the following steps:

[0062] Through the S2 flow design, obtain the initial flow path WON of the engine fan booster stage; select the split-ring type line design region BOC section in the initial flow path WON (split point O point).

[0063] As Figure 1 shown, establish a coordinate system OXY with the split point 0 of the split-ring type line design region BOC section as the origin.

[0064] According to the coordinate system OXY, obtain: the coordinates of point O (0, 0), the coordinates of point B slope the coordinates of point C slope

[0065] Establish the ellipse equation of the upper part OB section of the split ring in the coordinate system OXY, and solve to obtain the type line of the OB section. The specific method includes:

[0066] According to the ellipse equation the coordinates of point B and the slope of point B to obtain the following system of equations;

[0067]

[0068] Solve for a1 and b1 to obtain the type line equation of the OB section

[0069] Establish the ellipse equation of the lower part OC section of the split ring in the coordinate system OXY, and solve to obtain the type line of the OC section. The specific method includes:

[0070] According to the ellipse equation the coordinates of point C and the slope of point C

[0071] to obtain the following system of equations;

[0072]

[0073] Solve for a2 and b2 to obtain the type line equation of the OC section

[0074] Combine the upper OB section profile line and the lower OC section profile line of the flow splitting ring to form a complete flow splitting ring profile line.

[0075] Perform numerical simulation calculations on the complete flow splitting ring profile line formed by the combination, and adjust the complete flow splitting ring profile line according to the numerical simulation calculation results and design requirements. Specifically, it includes:

[0076] Perform numerical simulation calculations on the fan boost stage scheme of the complete flow splitting ring profile line formed by the combination, analyze the local flow field details of the flow splitting ring, and determine the radial and / or axial offset of the split flow point according to design experience and specification requirements. Offset the split flow point 0 radially and / or axially, and use the offset split flow point as the new coordinate origin O′ to construct a transformed coordinate system O′X′Y′.

[0077] Convert the coordinates of point B, the slope of point B, the coordinates of point C, and the slope of point C into the coordinate system O′X′Y′;

[0078] Re-establish the elliptic equation of the upper O′B section of the flow splitting ring in the coordinate system O′X′Y′, and re-solve to obtain the profile line of the O′B section;

[0079] Re-establish the elliptic equation of the lower O′C section of the flow splitting ring in the coordinate system O′X′Y′, and re-solve to obtain the profile line of the O′C section;

[0080] Combine the newly obtained upper O′B section profile line and the lower O′C section profile line of the flow splitting ring to form a new complete flow splitting ring profile line.

[0081] By moving the initial split flow point within a certain range axially and / or radially, multiple flow splitting ring profile lines are obtained. Through numerical calculation and comparative analysis of each flow splitting ring profile line, comprehensively evaluate the characteristics of the fan boost stage and the local flow field, select a better flow splitting ring scheme to ensure the overall engine bypass ratio requirement, optimize the local flow field, and improve the performance of the fan boost stage.

[0082] Designs such as an upward deflection of the flow splitting ring profile line can be achieved by using a positive radial offset for the split flow point 0, a downward deflection of the flow splitting ring profile line can be achieved by using a negative radial offset for the split flow point 0, a forward extension of the flow splitting ring profile line can be achieved by using a negative axial offset for the split flow point 0, or a backward contraction of the flow splitting ring profile line can be achieved by using a positive axial offset for the split flow point 0.

[0083] As Figure 2 shown, the Ori profile line is the initial profile line, and the New profile line is the flow splitting ring profile line obtained by solving using the method provided in the embodiment of the present application. The split flow point 0 has no axial or radial offset.

[0084] As Figure 3As shown, the Ori type line is the initial type line, and the UP and DOWN type lines are the shunt ring type lines obtained by solving using the method provided in the embodiments of the present application. Compared with the Ori type line, the UP type line uses a positive radial offset at the dividing point 0 to achieve an upward deflection of the shunt ring type line; compared with the Ori type line, the DOWN type line uses a negative radial offset at the dividing point 0 to achieve a downward deflection of the shunt ring type line.

[0085] As Figure 4 shown, the Ori type line is the initial type line, and the FRONT and BACK type lines are the shunt ring type lines obtained by solving using the method provided in the embodiments of the present application. Compared with the Ori type line, the FRONT type line uses a negative axial offset at the dividing point 0 to achieve a forward extension of the shunt ring type line; compared with the Ori type line, the BACK type line uses a positive axial offset at the dividing point 0 to achieve a backward contraction of the shunt ring type line.

[0086] Based on the above embodiments of the present invention, without explicit negation, the technical features of one embodiment can be beneficially combined with one or more other embodiments.

[0087] In the description of the present invention, it should be understood that using terms such as "first", "second", "third", etc. to limit components is only for the convenience of distinguishing the above components. Without additional declaration, the above terms have no special meaning, so they cannot be understood as limiting the protection scope of the present invention.

[0088] Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them; although the present invention has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that: it is still possible to modify the specific implementation manners of the present invention or perform equivalent replacements for some technical features; without departing from the spirit of the technical solutions of the present invention, they should all be covered within the scope of the technical solutions claimed by the present invention.

Claims

1. A design method for a shunt ring-shaped wire, characterized in that, Including: Through the S2 flow path design, obtain the initial flow path WON of the engine fan booster stage; Select the shunt ring profile design area BOC section in the initial flow path WON; Establish a coordinate system OXY with the split point 0 of the shunt ring profile design area BOC section as the origin; Obtained according to the coordinate system OXY: The coordinates of point O are (0, 0), and the coordinates of point B are The slope of point B The coordinates of point C The slope of point C Establish an ellipse equation for the upper part OB section of the shunt ring in the coordinate system OXY, and solve to obtain the OB section profile; Establish an ellipse equation for the lower part OC section of the shunt ring in the coordinate system OXY, and solve to obtain the OC section profile; Combine the upper part OB section profile and the lower part OC section profile of the shunt ring to form a complete shunt ring profile; Conduct numerical simulation calculations on the formed complete shunt ring profile, and adjust the complete shunt ring profile according to the numerical simulation calculation results and design requirements; The method for adjusting the complete shunt ring profile includes: offsetting the split point 0 radially and / or axially, constructing a transformed coordinate system O′X′Y′, and re-obtaining the complete shunt ring profile according to the transformed coordinate system O′X′Y′.

2. The shunt ring type line design method according to claim 1, characterized in that, The method for establishing an ellipse equation for the upper part OB section of the shunt ring in the coordinate system OXY and solving to obtain the OB section profile includes: According to the ellipse equation Coordinates of point B And the slope of point B The following system of equations is obtained; Find a1 and b1 to obtain the equation of the OB segment curve 0 ≤ X ≤ X B , Y ≥ 0.

3. The shunt ring type line design method according to claim 1, characterized in that The method for establishing an ellipse equation for the lower part OC section of the shunt ring in the coordinate system OXY and solving to obtain the OC section profile includes: According to the ellipse equation Coordinates of point C And the slope of point C The following system of equations is obtained; Find a2 and b2 to obtain the equation of the OC segment curve 0 ≤ X ≤ X C , Y ≤ 0.

4. The shunt ring type line design method according to claim 1, wherein The method for re-obtaining the complete shunt ring profile includes: Convert the coordinates of point B, the slope of point B, the coordinates of point C, and the slope of point C to the coordinate system O′X′Y′; Re-establish an ellipse equation for the upper part O′B section of the shunt ring in the coordinate system O′X′Y′, and solve to obtain the O′B section profile; Re-establish an ellipse equation for the lower part O′C section of the shunt ring in the coordinate system O′X′Y′, and solve to obtain the O′C section profile; Combine the re-obtained upper part O′B section profile and the lower part O′C section profile of the shunt ring to form a new complete shunt ring profile.

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