Verification method of cooling structure design
By distinguishing the aircraft cooling structure into simple channels and complex channels, and performing equivalent verification, the traditional flow resistance verification test problem is solved, and faster and more economical structural optimization and verification is achieved.
Patent Information
- Application Number
- CN202411776925.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-05
- Publication Date
- 2025-02-25
AI Technical Summary
In the design of aircraft cooling structures, traditional flow resistance verification tests require processing of complete experimental models, which are long, costly, and slow iteration speed.
The cooling structure is divided into simple channels and complex channels. The simple channels are equivalent to circular tubes. Verification models are made separately, and equivalent verification test parts are connected to and used for flow resistance testing. The structural design is optimized based on the test results.
Save processing time, reduce costs, facilitate iterative update verification of cooling structures, and significantly shorten the cycle from design to production.
Smart Images
Figure CN119514041A_ABST
Abstract
Description
Technical Field
[0001] The invention relates to the field of aircraft cooling structure design, in particular to a verification method for cooling structure design. Background Art
[0002] The tail of a powered aircraft is equipped with a turbine engine, and control surfaces are arranged on both sides and the upper side of the fuselage. The tail nozzle of the engine will spray high-temperature airflow, and the tail fuselage and surrounding control surfaces will also be in a high temperature environment. Therefore, when designing this tail fuselage, active / passive thermal protection is often required. Some cooling structures are pipes attached to the high-temperature area, and some are made into a whole with the fuselage skin.
[0003] The flow resistance design of the channel in the cooling structure is very important, and has a significant impact on the energy consumption of the cooling system, the system weight, and the final cooling effect. However, in the early structural design, especially for large parts, due to the complexity of the channels in the cooling structure, the engineering estimation and simulation calculation of the flow resistance often have large errors. In the traditional flow resistance verification test, the entire structural design drawing needs to be processed into a complete experimental model and then the flow resistance verification test is carried out as a whole. It takes a long time and high cost to process a complete experimental model. In addition, when the cooling structure is updated in the later stage, a new experimental model needs to be reprocessed for flow resistance verification testing, and the iteration speed is slow. Summary of the invention
[0004] The technical problem that the present application aims to solve is to provide a verification method for cooling structure design, in which the cooling structure is divided into simple channels and complex channels. The simple channels are equivalent to circular tubes, and the complex channels are made separately. The simple channels and the complex channels are connected to build equivalent verification test pieces for flow resistance testing, or flow resistance tests are performed separately. The structural design is optimized according to the test results, and the optimized simple channels or complex channels are directly replaced into the equivalent verification test pieces, which saves processing time, reduces costs, and facilitates the verification of iterative updates of the cooling structure in the later stage.
[0005] The present application adopts the following technical solution: A verification method for cooling structure design, comprising the following steps: S1. In the component structure design stage, the cooling structure preliminarily designed in the structure design drawing is extracted, and the cooling structure includes a plurality of cooling channels; S2, analyzing the cooling channels and separating simple channels and complex channels; S3a, treating the irregular cross section in the simple channel as an equivalent circular cross section, and finding the radius of the equivalent circular cross section; using circular metal tubes with the same radius as the equivalent circular cross section to be detachably connected to each other, and constructing a simple structure verification model; S3b, separately making a complex structure verification model, wherein the complex structure verification model includes the complex channel; S4. The simple structure verification model and the complex structure verification model are detachably connected to form an equivalent verification test piece; S5. Perform a flow resistance test on the equivalent verification test piece under the simulated actual operating conditions of the aircraft to determine whether the total flow resistance meets the design requirements. If so, the verification is terminated. S6. If the design requirements are not met, disassemble the equivalent verification test piece and perform flow resistance tests on the simple structure verification model and the complex structure verification model respectively; or disassemble the simple structure verification model and the complex structure verification model, and perform flow resistance tests on the simple channels and complex channels at local locations in turn, until the location where the flow resistance is significantly different from the design requirements is found; S7. Optimize the structure or shape of simple channels or complex channels at locations where the flow resistance is significantly different from the design requirements, and repeat steps S2 to S6 until the total flow resistance meets the design requirements, thereby obtaining a cooling structure that meets the design requirements.
[0006] Furthermore, the simple channel is a long straight, circular or regularly oriented flow channel with a consistent cross section.
[0007] Furthermore, the annular reciprocating pipeline and the rudder surface linear reciprocating pipeline of the same cross-sectional shape are regarded as simple channels.
[0008] Furthermore, the complex channel is a multi-tap section, a section with variable cross-sections and / or a continuous bend section in the cooling structure.
[0009] Furthermore, the irregular cross section in the simple channel is equivalently treated as an equivalent circular cross section, and the radius of the equivalent circular cross section is calculated. The equivalent formula is:
[0010] Where: is the hydraulic radius; A is the cross-sectional area of the polygon; S is the perimeter of the polygonal cross section; r is the equivalent circular tube radius.
[0011] Preferably, a simple structure verification model is constructed by connecting the ends of each metal pipe using a universal joint with the same diameter, and the metal pipe is shaped by bending or using a mold to assist in shaping.
[0012] Preferably, the complex structure verification model is made by 3D printing, and a universal joint is fixed at the outlet of the complex channel; For the flow resistance test of the complex structure verification model, the flow resistance of the corresponding complex channel is measured by blocking the joints of the remaining complex channels.
[0013] Further preferably, the universal joint is a ball head-cone sealing connector.
[0014] Preferably, in the flow resistance test, a differential pressure sensor and a flow sensor are used to measure the flow resistance.
[0015] Further preferably, the simulation of the actual use condition of the aircraft performs a flow resistance test on the equivalent verification test piece, performs flow resistance tests for different flow conditions respectively, obtains the flow-flow resistance relationship of the equivalent verification test piece, and determines whether the total flow resistance meets the design requirements.
[0016] Compared with the prior art, the present invention has the following beneficial effects: For large parts, the cost of experimental models is high and the cycle is long. The need to wait for the experimental model to be adjusted during the structural optimization process makes the flow resistance test take a long time, which is not conducive to design iteration. The present application can quickly carry out flow resistance design and verification iteration for simple channels or complex channels in local locations, greatly shortening the cycle from design to production. The present application divides the internal cooling channels of the aircraft into simple channels and complex channels, replaces the simple channels with equivalent circular metal tubes, and only remodels and processes the local complex structure verification model. Later, when the aircraft is remodeled and updated, it only needs to disassemble and update the local area that has changed its position, which reduces the test cost and time and enables faster iteration and verification. BRIEF DESCRIPTION OF THE DRAWINGS
[0017] Figure 1 This is a schematic diagram of the aircraft body structure of an embodiment of the present application; Figure 2 This is a schematic diagram of the cooling structure inside the aircraft body of the embodiment of the present application; Figure 3 This is a schematic diagram of a simple structure verification model for an embodiment of the present application; Figure 4 This is a schematic diagram of a local complex structure verification model at the fuselage-control surface fusion of the embodiment of the present application; In the figure, 1. fuselage; 2. rudder surface; 3. tail nozzle; 4. cooling structure; 41. simple channel; 42. complex channel; 5. universal joint. DETAILED DESCRIPTION
[0018] To make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be described clearly and completely in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them.
[0019] Therefore, the following detailed description of the embodiments of the present invention is not intended to limit the scope of the invention claimed for protection, but merely represents some embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.
[0020] Example 1 Please refer to the attached drawings of the specification. The internal cooling structure of the aircraft body mainly includes the body annular cooling pipeline, the leading edge cooling pipeline of the control surface 2, the peripheral cooling pipeline of the tail nozzle 3, etc.
[0021] This embodiment takes the internal cooling structure of an aircraft body 1 as an example to provide a verification method for the cooling structure design, including the following steps: S1. In the component structure design stage, extract the cooling structure 4 preliminarily designed in the structure design drawing, where the cooling structure 4 includes a cooling channel; S2, analyzing the cooling channels, and separating simple channels 41 and complex channels 42 therefrom; S3a, treating the irregular cross section in the simple channel 41 as an equivalent circular cross section, and finding the radius of the equivalent circular cross section; using a circular metal tube with the same radius as the equivalent circular cross section, shaping the metal tube into a shape close to the structural design, and connecting them detachably to each other, to construct a simple structure verification model; S3b, the cooling channel at the fuselage-control surface fusion is relatively complex, so a separate complex structure verification model is made; S4. The simple structure verification model and the complex structure verification model are detachably connected to form an equivalent verification test piece; S5. A differential pressure sensor and a flow sensor are arranged before and after the equivalent verification test piece to measure the total flow resistance value, and a flow resistance test is performed on the equivalent verification test piece simulating the actual use condition of the aircraft to determine whether the total flow resistance meets the design requirements. If so, the verification is terminated; S6. If the design requirements are not met, the equivalent verification test piece is disassembled, and the flow resistance test is performed on the simple structure verification model and the complex structure verification model respectively; or the simple structure verification model and the complex structure verification model are disassembled, and the flow resistance test is performed on the simple channel 41 and the complex channel 42 at the local position in sequence, until the position where the flow resistance is significantly different from the design requirements is found; S7. Optimize the structure or shape of the simple channel 41 or the complex channel 42 at the position where the flow resistance is significantly different from the design requirements, such as increasing the turning radius of the cooling channel, and repeat steps S2 to S6 until the total flow resistance meets the design requirements, thereby obtaining a cooling structure that meets the design requirements.
[0022] In this embodiment, the internal cooling channels of the aircraft in the component structure design are divided into simple channels 41 and complex channels 42. The simple channel 41 is equivalent to a circular tube to construct a simple structure verification model, and the complex channel 42 is constructed as a complex structure verification model. The simple structure verification model and the complex structure verification model are combined to build an equivalent verification test piece for flow resistance testing. If the flow resistance does not meet the design requirements, flow resistance tests are carried out separately, and the parts with large deviations from the design requirements are found one by one, and the structure is optimized in a targeted manner. The optimized simple channel 41 or complex channel 42 is directly replaced with the equivalent verification test piece, which saves processing time and reduces costs. The simple structure verification model and the complex structure verification model can be disassembled at will to facilitate the verification of the iterative update of the cooling structure in the later stage.
[0023] Furthermore, the simple channel 41 is a long straight, circular or relatively regular flow channel with a consistent cross section. The annular reciprocating pipeline and the linear reciprocating pipeline of the rudder surface 2 with the same cross section shape can be regarded as a simple channel 41.
[0024] Furthermore, the complex channel 42 is a multi-branch joint section, a section with variable cross-section and / or a continuous curved section in the cooling structure 4. The rudder-fuselage transition section is a multi-branch intersection, and the pipeline changes in a complex manner following the special-shaped surface of the fuselage 1, and the cross-sectional area also changes with the wall thickness and space of the internal structure, which can be regarded as a complex cooling structure.
[0025] In the cooling structure of the aircraft, the simple channel 41 is mainly the resistance along the way, accounting for a small proportion of the system flow resistance. The complex channel 42 has a complex flow, which is prone to separation, turbulence and other phenomena in the turning, expansion and contraction sections, consumes a lot of energy, and accounts for a large proportion of the system flow resistance. In this embodiment, the simple channel 41 is replaced by a metal round tube, and the complex channel 42 is 3D printed to restore the real characteristics, so that the final equivalent verification test results are highly accurate and reliable.
[0026] Furthermore, the irregular cross section in the simple channel 41 is equivalently processed into an equivalent circular cross section, and the radius of the equivalent circular cross section is calculated. The equivalent formula is:
[0027] Where: is the hydraulic radius; A is the cross-sectional area of the polygon; S is the perimeter of the polygonal cross section; r is the equivalent circular tube radius.
[0028] Preferably, universal joints 5 of the same diameter are provided at each end of the metal tube, and the metal tube is constructed into a simple structural verification model. Usually, the fuselage section of an aircraft is a simple shape such as a circle or an ellipse, and the shape of the internal channel is also relatively simple. The metal tube is moderately soft and hard, and is easy to bend to construct the real physical shape of the channel. If the channel direction is more complicated, a mold can also be used for auxiliary shaping.
[0029] Preferably, the complex structure verification model is made by 3D printing, and a universal joint 5 of matching diameter is welded or processed at the outlet of the complex channel; for the flow resistance test of the complex structure verification model, the flow resistance of the corresponding complex channel is measured by blocking the joints of the remaining complex channels.
[0030] Further preferably, the universal joint 5 is a ball head-cone surface sealing connector, which contains a sealing structure.
[0031] Further preferably, the simulation of the actual use condition of the aircraft performs a flow resistance test on the equivalent verification test piece, performs flow resistance tests for different flow conditions respectively, obtains the flow-flow resistance relationship of the equivalent verification test piece, and determines whether the total flow resistance meets the design requirements.
[0032] A person skilled in the art should understand that the discussion of any of the above embodiments is merely illustrative and is not intended to imply that the scope of protection of the present application is limited to these examples. In line with the concept of the present application, the technical features in the above embodiments or different embodiments may be combined, the steps may be implemented in any order, and there are many other variations of different aspects of one or more embodiments of the present application as described above, which are not provided in detail for the sake of simplicity.
[0033] One or more embodiments of the present application are intended to cover all such substitutions, modifications and variations that fall within the broad scope of the present application. Therefore, any omissions, modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of one or more embodiments of the present application should be included in the protection scope of the present application.
Claims
1. A verification method for cooling structure design, characterized in that: The steps include: S1. In the component structure design stage, extracting a cooling structure (4) preliminarily designed in a structure design drawing, wherein the cooling structure (4) includes a plurality of cooling channels; S2, analyzing the cooling channel (4) and separating the simple channel (41) and the complex channel (42) therefrom; S3a, treating the irregular cross section in the simple channel (41) as an equivalent circular cross section, and finding the radius of the equivalent circular cross section; using circular metal tubes with the same radius as the equivalent circular cross section to be detachably connected to each other, and constructing a simple structure verification model; S3b, separately making a complex structure verification model, wherein the complex structure verification model includes the complex channel (42); S4. The simple structure verification model and the complex structure verification model are detachably connected to form an equivalent verification test piece; S5. Perform a flow resistance test on the equivalent verification test piece under the simulated actual operating conditions of the aircraft to determine whether the total flow resistance meets the design requirements. If so, the verification is terminated. S6. If the design requirements are not met, the equivalent verification test piece is disassembled, and the flow resistance test is performed on the simple structure verification model and the complex structure verification model respectively; or the simple structure verification model and the complex structure verification model are disassembled, and the flow resistance test is performed on the simple channel (41) and the complex channel (42) at the local position in turn, until the position where the flow resistance is significantly different from the design requirements is found; S7. Optimize the structure or shape of the simple channel (41) or the complex channel (42) at the position where the flow resistance is significantly different from the design requirement, and repeat steps S2 to S6 until the total flow resistance meets the design requirement, thereby obtaining a cooling structure that meets the design requirement.
2. The verification method for cooling structure design according to claim 1, characterized in that: The simple channel (41) is a long straight, circular or regularly oriented flow channel with a uniform cross section.
3. The verification method for cooling structure design according to claim 2, characterized in that: The annular reciprocating pipeline and the linear reciprocating pipeline of the rudder surface (2) of the same cross-sectional shape are regarded as simple channels (41).
4. The verification method for cooling structure design according to claim 1, characterized in that: The complex channel (42) is a multi-tap section, a section with variable cross-sections and / or a continuous bend section in the cooling structure (4).
5. The verification method for cooling structure design according to claim 1, characterized in that: The irregular cross section in the simple channel (41) is equivalently treated as an equivalent circular cross section, and the radius of the equivalent circular cross section is calculated. The equivalent formula is: Where: is the hydraulic radius; A is the cross-sectional area of the polygon; S is the perimeter of the polygonal cross section; r is the equivalent circular tube radius.
6. The verification method for cooling structure design according to claim 1, characterized in that: A simple structure verification model is constructed by connecting the ends of each metal pipe using a universal joint (5) of the same diameter, and the metal pipe is shaped by bending or using a mold to assist in shaping.
7. The verification method for cooling structure design according to claim 1, characterized in that: The complex structure verification model is made by 3D printing, and a universal joint (5) is fixed at the outlet of the complex channel (42); For the flow resistance test of the complex structure verification model, the flow resistance of the corresponding complex channel (42) is measured by blocking the joints of the remaining complex channels (42).
8. The verification method for cooling structure design according to claim 6 or 7, characterized in that: The universal joint (5) is a ball head-cone surface sealing connector.
9. The verification method for cooling structure design according to claim 1, characterized in that: In the flow resistance test, a differential pressure sensor and a flow sensor are used to measure the flow resistance.
10. The verification method of cooling structure design according to claim 9, characterized in that: The equivalent verification test piece is tested for flow resistance under the simulated actual operating conditions of the aircraft, and flow resistance tests are performed for different flow conditions to obtain the flow-resistance relationship of the equivalent verification test piece, and to determine whether the total flow resistance meets the design requirements.