A simplified design method for stiffness design of elastic ring support structure

Abstract

The present invention relates to a simplified design method for the stiffness design of an elastic ring type support structure. By studying the stress and deformation law of the elastic ring in the elastic ring type support structure, a real elastic ring structure is adopted, and corresponding loads and constraints are applied to the elastic ring, so that the displacement and stress cloud diagram changes of the elastic ring in the elastic ring type support structure and the individual elastic ring are consistent, so as to simulate the real deformation and stress distribution of the elastic ring type support structure, and determine the position of the maximum dangerous stress point based on this, so as to facilitate the structural optimization and life calculation of the elastic ring type support structure. According to the relationship between the elastic ring force and the displacement deformation, the stiffness of the simplified model of the single elastic ring is accurately obtained and compared with the stiffness of the elastic ring type support structure for verification. While ensuring the accuracy of the stiffness calculation result, the calculation efficiency is also improved and the time of finite element calculation is shortened, so that the stiffness design of the elastic ring type support structure can be realized quickly and accurately.

Description

Technical Field

[0001] The invention relates to the technical field of aeroengines, and in particular to a simplified design method for rigidity design of an elastic ring-type support structure. Background Art

[0002] During the overall structural design stage of aircraft engines, it is very difficult to adjust the critical speed by changing the rotor structural parameters such as the shaft size and fulcrum position. An elastic support structure is often used to adjust the critical speed of the rotor system. The critical speed of the rotor system is adjusted by changing the support stiffness of the elastic support structure. Common elastic support structures include elastic ring support structures and squirrel cage elastic support structures. The elastic ring support structure has the advantages of small mass, easy processing and assembly, etc. In addition, the elastic ring support structure can absorb and eliminate the vibration energy generated by the rotor system through the deformation of the elastic ring support structure itself and the internal resistance of its material, thereby reducing the vibration amplitude and changing the strain energy. It has been used more and more widely. Therefore, it is very important to optimize the design steps of the elastic ring support structure and accurately calculate and design the stiffness of the elastic ring support structure. However, due to the relatively complex structure of the elastic ring support structure, the current design method for the elastic ring support structure often adopts the following methods: Figure 1 The finite element model of the elastic ring support structure shown in the figure is analyzed and calculated, where 1 is the bearing seat; 3 is the elastic ring; 4 and 2 are the inner and outer bushings respectively; 5 simulates the outer ring of the bearing; 6 is the contact between the outer ring of the bearing and the inner bushing; 7 is the contact between the inner and outer bosses and the inner and outer bushings. There are many nodes and nonlinear factors such as contact, friction, and sliding are involved, which results in a long simulation calculation time and leads to design difficulties. In addition, the design process depends on the experience of the designers and is trial-and-error in nature. The fatigue strength of different schemes varies greatly, and it is difficult to meet the requirements of stiffness and fatigue strength at the same time. Repeated parameter adjustment design is required, which will consume a lot of time on parameter adjustment, greatly affecting the design process of the stiffness of the elastic ring support structure, and is not conducive to further studying the simulation method of the engine support stiffness. How to quickly, effectively and accurately design the stiffness of the elastic ring support structure has become an urgent problem to be solved.

[0003] The existing simplified methods for elastic ring support structure stiffness design are mainly divided into two categories. One is the theoretical analysis method to calculate stiffness. The structural characteristics of the elastic ring are multiple bosses evenly distributed, a large number of ring segments, a small span, and the ring thickness is much smaller than the ring radius. Therefore, in the literature of Artemov's theoretical analysis, each individual ring segment is simplified to a straight beam with fixed supports at both ends. The stiffness calculation formula can be derived by the material mechanics method, and each simplified ring segment is analyzed to obtain the overall stiffness of the elastic ring. The schematic diagram of the elastic ring structure is shown in Figure 2 As shown, D is the inner diameter, the number of bosses is n, b is the boss length, △ is the boss height, s is the wall thickness, and L is the width.

[0004] Another method is to simplify the finite element model of the elastic ring support structure. In the literature "Experimental and numerical investigations on novel models for mechanical behaviors of the elastic ring in aero-engine" (DOI: 10.1177 / 09544062211013066), since the elastic ring support structure is a symmetrical structure, the elastic ring support structure is simplified into a half ring, and a two-dimensional finite element model is used instead of a three-dimensional finite element model. The effectiveness of the simplified result is proved by stiffness calculation, which saves calculation time; in the invention patent CN109583062A, the elastic ring support structure is discretized into several elastic units, each of which is composed of an inner boss and half of two adjacent outer bosses. Since the lower boss is the main force and deformation area, the elastic unit is simulated by finite element to obtain the stiffness of the elastic unit. Different elastic units correspond to springs with different stiffness. The work done by each elastic unit is calculated, and the overall stiffness of the elastic ring can be obtained by the energy conservation constant, which effectively reduces the calculation amount of finite element analysis and improves calculation efficiency; in the literature "Studying In the study of Manufacturing Tolerance Influence on the Performance of GTE Rotor Elastic Rings (DOI: 10.1016 / j.proeng.2017.02.348), the ring segments of the elastic ring support structure were simplified into plates in contact with each other, the boss features were retained, and the mathematical relationship between the simplified structural stiffness and the elastic ring support structure stiffness was obtained by fitting, saving calculation time. The simplified model corresponding to the above background scheme is as follows: Figure 3 shown.

[0005] Although the simplified method for stiffness design of elastic ring support structure mentioned above can realize the rapid design of stiffness of elastic ring support structure to a certain extent, there are still some problems. First, the theoretical analysis oversimplifies the geometric model of elastic ring support structure and ignores the influence of many structural parameters on the overall stiffness, resulting in a large deviation between the stiffness results obtained by theoretical analysis and the stiffness results obtained by simulation.

[0006] Secondly, in terms of finite element simplified models, such as Figure 3 The figure shows a simplified diagram of the finite element model of the existing elastic ring support structure. In the literature 1, the elastic ring support structure is analyzed as follows: Figure 3(a) shows a simplified semi-ring, and verifies that the two-dimensional model can effectively replace the three-dimensional model for finite element calculation. The finite element calculation model is similar to the real solid model, and the same constraints are used for calculation. The calculation results are accurate, but the structure is still complex. Multiple contact pairs still need to be set at the outer ring of the outer bushing and the inner ring of the bearing seat, the outer boss of the elastic ring and the inner ring of the outer bushing, the inner boss of the elastic ring and the outer ring of the inner bushing, and the inner ring of the inner bushing and the outer ring of the bearing. This still takes a long time in terms of calculation time, which makes it difficult to design the elastic ring support structure under the conditions of specified installation space and specified stiffness, and still needs to be further simplified;

[0007] In the above invention patent, the distribution of the boss of the elastic ring support structure is divided into several elastic units, such as Figure 3 As shown in (b), the stiffness of the whole ring is inferred by calculating the finite element stiffness of the elastic unit, thereby achieving the goals of accurate calculation results, shortening calculation time, and improving design efficiency. However, when analyzing the elastic unit, due to the simplification of the structure, the geometric model is quite different from the elastic ring support structure. From the calculation results, only applying load to the elastic unit cannot effectively obtain the displacement deformation and stress distribution of the elastic ring, which can easily cause excessive local displacement and stress concentration. There is a large gap with the actual structure of the elastic ring, and it is difficult to determine the location where the maximum dangerous stress of the elastic ring support structure appears. It is impossible to further carry out structural optimization and life calculation of the elastic ring support structure, and it is impossible to meet the requirements of stiffness and fatigue strength at the same time.

[0008] In Reference 2, the elastic ring support structure is simplified to a plate with boss features in contact with each other. By calculating the stiffness of the plate, the mathematical relationship between the stiffness of the plate and the elastic ring support structure is derived. Due to the simplicity of the model, the calculation time is greatly saved, and the mathematical formula obtained by fitting is obtained. However, the fitting result is a complex power function, and the fitting function only analyzes the influence of the diameter on the stiffness, and does not analyze the influence of parameters such as the number of bosses, boss height, boss length, and elastic ring wall thickness on the stiffness and the results of the fitting function. In addition, it only targets the working condition where the elastic ring boss is on top, and does not consider the working condition where the boss is on the bottom. It has a certain trial and error component and is only effective within a specific parameter variation range. The elastic ring support structure is affected by multiple parameters and the design parameter range is relatively wide. Therefore, this simplified scheme has great limitations and is not universal.

[0009] From the above problems, it can be seen that the current simplified and rapid design method for the stiffness design of elastic ring support structures, the simplified finite element model is more accurate than the stiffness calculation results of theoretical analysis. However, the problem with the simplified finite element model is that it is often structurally different from the actual structure and cannot reflect the actual deformation of the elastic ring support structure. The method does not meet the universality of multi-parameter changes and cannot effectively realize the simplified design of the stiffness design of the elastic ring support structure. Further research is still needed. Summary of the invention

[0010] In view of the above problems, the purpose of the present invention is to provide a simplified design method for the stiffness design of an elastic ring support structure. In view of the problem that the finite element simplified model of the current elastic ring support structure is far from the real structure in the background technology, and cannot reflect its real deformation, by studying the stress and deformation law of the elastic ring in the elastic ring support structure, using the real elastic ring structure, applying corresponding loads and constraints to the elastic ring, and achieving the consistency of the displacement and stress cloud map changes of the elastic ring in the elastic ring support structure and the separate elastic ring, so as to achieve the simulation of the real deformation and stress distribution of the elastic ring support structure, and determine the position of the maximum dangerous stress point based on this, so as to facilitate the structural optimization and life calculation of the elastic ring support structure. According to the relationship between the elastic ring force and the displacement deformation, the stiffness of the single-ring simplified model of the elastic ring is accurately obtained and compared with the stiffness of the elastic ring support structure. While ensuring the accuracy of the stiffness calculation result, it also improves the calculation efficiency and shortens the finite element calculation time, and can quickly and accurately realize the stiffness design of the elastic ring support structure.

[0011] The technical solution adopted by the present invention is as follows:

[0012] The present invention proposes a simplified design method for the stiffness design of an elastic ring support structure, which adopts a simplified model of a single elastic ring to design the stiffness of the elastic ring support structure, thereby achieving fast, efficient and accurate calculation and meeting the universal requirements of multi-parameter changes. The method comprises the following steps:

[0013] S1. Determine the installation space and support stiffness of the elastic ring support structure, and give the parameters of the elastic ring support structure;

[0014] S2. Establishing a finite element model of the elastic ring support structure including two working conditions: the boss is on the top and the boss is on the bottom;

[0015] S3. Summarize the deformation law of the elastic ring in the elastic ring support structure and conduct stress analysis;

[0016] S4. Based on the results of force analysis, the stiffness calculation formula of the simplified single-ring model of the linear ring is deduced, and the load application and constraint methods are explored;

[0017] S5, establishing a simplified finite element model of a single elastic ring under two conditions: the boss is on the top and the boss is on the bottom, and exploring the load application and constraint method obtained in step S4, and performing finite element calculation on the simplified model of the single elastic ring;

[0018] S6. Compare the displacement and stress cloud diagram of the elastic ring in the elastic ring support structure with the calculation results of the simplified model of the elastic ring;

[0019] S7. Compare the stiffness of the two models under different loads;

[0020] S8. Analyze the parameter stiffness sensitivity of the elastic ring support structure and the simplified model, and compare it with the IS theoretical analysis;

[0021] S9. Compare the calculation time of the three-dimensional model of the elastic ring support structure, the two-dimensional model of the elastic ring support structure, and the single-ring simplified model.

[0022] Furthermore, the step S2 specifically includes: according to the given elastic ring support structure parameters, establishing a finite element model of the elastic ring support structure including two working conditions of the boss on top and the boss on the bottom, and performing finite element calculation to obtain the displacement, stress cloud map and stiffness value of the elastic ring support structure.

[0023] Furthermore, the step S3 specifically includes: extracting the calculation results of the elastic ring in the elastic ring support structure according to the calculation results obtained in step S2, summarizing the deformation law of the elastic ring in the elastic ring support structure, and performing force analysis.

[0024] Furthermore, the step S6 specifically includes: comparing the displacement and stress cloud maps of the elastic ring support structure in step S2 and the elastic ring in step S5 with the calculation results of the elastic ring simplified model; judging whether the displacement deformation cloud map and stress cloud map of the elastic ring in the elastic ring support structure under different working conditions are consistent with the displacement cloud map and stress cloud map of the elastic ring simplified model.

[0025] Furthermore, the step S7 specifically includes: calculating the stiffness of the elastic ring single-ring simplified model according to the stiffness calculation formula of the elastic ring single-ring simplified model derived in step S4, comparing it with the stiffness value of the elastic ring support structure obtained in step S2, and further comparing the stiffness of the two models under different loads.

[0026] Furthermore, the step S8 specifically includes: analyzing the parameter stiffness sensitivity of the elastic ring support structure and the simplified model, analyzing the influence of the parameters on the stiffness of the elastic ring support structure by changing the elastic ring wall thickness, fillet radius, boss height, boss length, and boss number parameters, and calculating the stiffness values ​​of the single-ring simplified model boss-up and boss-down working conditions and the IS theoretical analytical solution within the parameter range.

[0027] Compared with the prior art, the present invention has the following beneficial effects:

[0028] 1. The elastic ring single ring simplified model is used to design the stiffness of the elastic ring support structure to achieve fast, efficient and accurate calculation and meet the universal requirements of multi-parameter changes;

[0029] 2. The semi-ring structure of the elastic ring is used for stiffness calculation. According to the deformation and stress of the elastic ring in the elastic ring support structure, the outer boss of the working area of ​​the elastic ring is fully constrained, and a radial load is applied to the inner boss of the working area;

[0030] 3. In the post-processing stage of the finite element simulation of the elastic ring, the y-direction displacement of the lowest inner boss in the elastic ring is extracted and regarded as the deformation of the elastic ring. The simplified model stiffness formulas under two working conditions are summarized to further calculate the stiffness of the elastic ring;

[0031] 4. Through simulation calculation, it is proved that the working condition of the simplified elastic ring model with the boss on top is closer to the stiffness value of the elastic ring support structure than the working condition with the boss on the bottom;

[0032] 5. Realized the displacement and stress cloud diagram of the single ring simplified model and the displacement and stress cloud diagram in the elastic ring support structure Figure 1 It can effectively analyze the location of the maximum stress point of the elastic ring support structure and further optimize the structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 It is a schematic diagram of an existing elastic ring support structure;

[0034] Figure 2 Schematic diagram of the existing elastic ring structure;

[0035] Figure 3 It is a simplified schematic diagram of the finite element model of the existing elastic ring support structure;

[0036] Figure 4 is the displacement cloud diagram of the elastic ring support structure in the y direction under the condition of the boss being at the bottom;

[0037] Figure 5 is the displacement cloud diagram of the elastic ring support structure in the y direction under the condition that the boss is on top;

[0038] Figure 6 It is a schematic diagram of a simplified model of a single ring of an elastic ring under the condition of a boss being at the bottom;

[0039] Figure 7 It is a schematic diagram of a simplified model of a single ring of an elastic ring with a boss on top;

[0040] Figure 8 It is a comparative schematic diagram of the displacement cloud diagram of the elastic ring under different working conditions;

[0041] Fig. 9 It is a comparative schematic diagram of elastic ring stress cloud diagram under different working conditions;

[0042] Fig.10 is a schematic diagram of stiffness comparison;

[0043] Fig.11 It is a schematic diagram of sensitivity verification of a single-loop simplified model;

[0044] Fig.12 This is a schematic diagram of the effect of the number of bosses on stiffness in a single-ring simplified model.

[0045] Among them, the figure markings are: 1-bearing seat; 2-outer sleeve; 3-elastic ring; 4-inner sleeve; 5-simulated bearing outer ring; 6-contact portion between bearing outer ring and inner sleeve; 7-contact portion between boss and sleeve; 8-contact portion between bearing seat and outer sleeve. DETAILED DESCRIPTION

[0046] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0047] The simplified design method for the stiffness design of an elastic ring support structure proposed in the present invention specifically comprises the following steps:

[0048] S1. In order to make the technical means and implementation process of the present invention easier to understand, the following is a further introduction combined with a specific example. According to the given installation space and support stiffness, the selected parameters are:

[0049] Table 1 Elastic ring support structure parameters

[0050]

[0051] S2. According to the parameters shown in Table 1, a finite element model of the elastic ring support structure is established, such as Figure 1 As shown in Figure 1, since the correctness of the simulation method has been verified by experiments in Literature 1, the contact pairs all use TARGE169 units and CONTA172 units, and constrain all degrees of freedom of the outer ring of the bearing seat, constrain the x-direction degrees of freedom of the symmetry line, and apply a vertical downward load to the inner ring surface of the outer ring of the bearing. The finite element simulation calculation of the model is performed, and the y-direction displacement of the elastic ring support structure is defined as the y-direction average displacement of the outer ring of the inner bushing minus the y-direction average displacement of the inner ring of the outer bushing, and the stiffness is the ratio of the applied y-direction load to the y-direction displacement;

[0052] S3. In the elastic ring support structure, the displacement deformation cloud diagram in the y direction under the two working conditions of the elastic ring boss on the top and the boss on the bottom is as follows: Figure 4 and Figure 5 As shown, in terms of displacement, it can be seen from the color of the cloud map that the deformation is mainly distributed on the elastic ring, the outer ring of the bearing, and the inner sleeve. The outer sleeve and the bearing seat have almost no displacement, and the displacement cloud map color of the lowest inner boss is basically consistent with the displacement cloud map color of the inner sleeve. Among them, the displacement cloud map color of the lowest inner boss under the upper working condition is closer to the displacement cloud map color of the inner sleeve, and the displacement cloud map color of the lowest outer boss is consistent with the displacement cloud map color of the outer sleeve. From this, the law is summarized, and the constraint setting is performed through the deformation and displacement relationship between the inner boss and the outer boss of the elastic ring in the elastic ring support structure. The average displacement of the inner sleeve can be replaced by the displacement of the lowest inner boss, and the outer bushing and the lowest outer boss have almost no displacement, which can be regarded as constraining all the degrees of freedom of the outer boss.

[0053] S4. In terms of loading force, a vertical downward load is applied to the elastic ring support structure during simulation calculation, such as Figure 1 As shown in the figure, from the force relationship, it can be known that the load is transferred through the outer ring of the bearing and the inner sleeve and applied to the boss in the lower half area. Therefore, when the elastic ring is loaded, a radial load is applied to the boss in the lower half area. Assuming that the vertical downward load applied to the elastic ring support structure is F, the calculation model is preliminarily simplified, and the half ring and two-dimensional model are used for calculation. The force applied to the two-dimensional elastic ring support structure model is F / 2L, as shown in Figure 6 The simplified model of a single elastic ring with the boss shown in the figure is under the lower condition, n 总 is the number of nodes of the loaded inner boss, n 总 =n A +n B , n A 、n B is the number of nodes of bosses A and B, α and β are the angles between the inner boss and the y-axis, and the radial load distribution of bosses A and B is F A With F B :

[0054]

[0055] The stiffness is the force divided by the displacement along the force direction. The displacement Δy along the y direction of the bottom boss can be extracted from Ansys, and the y-direction component of the radial load can be calculated. The elastic ring stiffness k of the simplified single-ring model of the boss under the following conditions can be obtained:

[0056]

[0057] like Figure 7 The simplified model of a single elastic ring with the boss in the upper condition is shown in Figure 1. 总is the number of nodes of the loaded inner boss, n 总 =n A +n B +n C , n A 、n B 、n C is the number of nodes of bosses A, B, and C, α and β are the angles between the inner boss and the y-axis, and the radial load distribution of bosses A, B, and C is F A 、F B With F C :

[0058]

[0059] It can be deduced that the elastic ring stiffness k of the simplified single-ring model of the boss under the upper condition is:

[0060]

[0061] S5. For the simplified model of elastic ring single ring, Figure 6 and Figure 7 The loads and constraints are set as shown, and the simulation results are as follows Figure 8 and Fig. 9 ;

[0062] S6. From step S5, it can be seen that the displacement deformation cloud map and stress cloud map of the elastic ring in the elastic ring support structure are different from the displacement cloud map and stress cloud map of the simplified model of the elastic ring. Figure 1 It is proved that the simplified model of elastic ring can effectively simulate the deformation of elastic ring in elastic ring support structure.

[0063] S7. Further analysis of the stiffness stability of the single-ring simplified model is carried out by Fig.10 It can be seen that the single-ring simplified model has linear stiffness, and the stiffness does not change with the increase of force. The stiffness of the boss is stable at 1.28e7N / m under the upper working condition, and the stiffness of the boss is stable at 1.45e7N / m under the lower working condition. The simulation stiffness of the elastic ring support structure is 1.27e7N / m. It can be seen that the boss of the elastic ring single-ring simplified model is closer to the simulation stiffness of the elastic ring support structure under the upper working condition, and the error is small within 0.8%, which is within the allowable range. It proves that the elastic ring single-ring simplified model can effectively simulate the stiffness of the elastic ring in the elastic ring support structure, and can realize the rapid design of the stiffness of the elastic ring support structure under the specified installation space and specified stiffness conditions.

[0064] S8. The above analysis only focuses on a specific model. In order to fully illustrate the effectiveness and demonstration effect of the present invention, the stiffness sensitivity of the elastic ring support structure parameters in Table 1 is analyzed, and the parameters such as wall thickness, fillet radius, boss height, boss length, and number of bosses are changed to analyze the influence of the parameters on the stiffness of the elastic ring support structure. The stiffness values ​​of the single-ring simplified model boss-up, boss-down working conditions and theoretical analytical solutions within the parameter range are calculated and compared with the stiffness of the elastic ring support structure to verify the universality of the simplified model. The theoretical analytical solution adopts the more accurate IS method, which considers the parameters of the elastic ring support structure more comprehensively and is closer to the actual working conditions to enhance persuasiveness.

[0065] The IS stiffness calculation formula for the elastic ring support structure is:

[0066]

[0067] in:

[0068]

[0069] D m =(D1+D2) / 2 (7)

[0070] H=Δ+s (8)

[0071] The structure of the elastic ring is as follows Figure 2 As shown, L is the width of the elastic ring, d is the fillet diameter, b1 is the width of the elastic ring, m is the number of bosses, E is the elastic modulus of the material, the wall thickness of the elastic ring is s, the boss height is Δ, D1 is the inner diameter of the elastic ring, and D2 is the outer diameter of the elastic ring.

[0072] Depend on Fig.11It can be seen that the change trends of the four working conditions, namely, single ring-boss on top, single ring-boss on bottom, elastic ring support structure, and theoretical analysis, are basically consistent under the influence of wall thickness, fillet radius, boss height, and boss length parameters. The stiffness change curve under the condition of single ring-boss on top is relatively similar to that of the elastic ring support structure, which proves the effectiveness of the simplified results. However, in the stiffness-boss length change curve diagram, the curves of the elastic ring support structure and the single ring-boss under the upper condition are not as good as the stiffness-wall thickness, stiffness-fillet radius, and stiffness-boss height curves. The reasons are analyzed as follows: ① The boss length directly affects the number of nodes. When the boss length is small, the number of nodes in the single-ring working condition is small, which affects the accuracy of the calculation results. ② When the boss length is large, the angle used in the simplified stiffness calculation formula is simplified to the angle of the middle position of the boss, and the position angle changes of different nodes of each boss are not considered. Therefore, the boss length of the simplified model has a greater impact on the stiffness, which is not very consistent with the stiffness-boss length curve of the elastic ring support structure, but the overall change trend is consistent, and the impact on the design results is small.

[0073] Depend on Fig.11 From the sensitivity analysis, it can be seen that the wall thickness of the elastic ring has the greatest influence on the stiffness of the elastic ring support structure. Therefore, only for the change of wall thickness, the stiffness of the elastic ring support structure with 6, 8, and 12 bosses and the stiffness of the simplified model of a single ring are compared to verify the effectiveness of the stiffness design calculation of the simplified model with different boss numbers. Fig.12 It can be seen that under the conditions of different numbers of bosses, the finite element calculation results of the simplified single ring correspond well to the finite element calculation results of the elastic ring support structure, especially when the boss is on the upper working condition, and are consistent with the change trend of the theoretical analysis, which proves the effectiveness of the simplified results.

[0074] S9, the calculation time and the number of nodes of different models are shown in Table 2. The calculation time of the three-dimensional model of the elastic ring support structure, the two-dimensional model of the elastic ring support structure, and the single-ring simplified model are compared. The calculation time is 835.3s, 74.0s, and 4.6s, respectively, proving that the calculation time required for the single-ring simplified model is much less than the three-dimensional and two-dimensional models of the elastic ring support structure, further illustrating the rapidity of the stiffness design of the present invention. The above description and examples illustrate the basic principles and advantages of the present invention, so the present invention can be used in the preliminary design stage of the stiffness design of the elastic ring support structure.

[0075] Table 2 Comparison of calculation time

[0076]

[0077] The embodiments described above are merely descriptions of preferred implementation modes of the present invention and are not intended to limit the scope of the present invention. Without departing from the design spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by ordinary technicians in this field should all fall within the protection scope determined by the claims of the present invention.

Claims

1. A simplified design method for the stiffness design of an elastic ring support structure, which adopts a simplified model of a single elastic ring to design the stiffness of an elastic ring support structure, realizes fast, efficient and accurate calculation, and meets the universal requirements of multi-parameter changes, and is characterized by: The method comprises the following steps: S1. Determine the installation space and support stiffness of the elastic ring support structure, and give the parameters of the elastic ring support structure; S2. Establishing a finite element model of the elastic ring support structure including two working conditions: the boss is on the top and the boss is on the bottom; S3. Summarize the deformation law of the elastic ring in the elastic ring support structure and conduct stress analysis; S4. Based on the results of force analysis, the stiffness calculation formula of the simplified single-ring model of the linear ring is deduced, and the load application and constraint methods are explored; S5, establishing a simplified finite element model of a single elastic ring under two conditions: the boss is on the top and the boss is on the bottom, and exploring the load application and constraint method obtained in step S4, and performing finite element calculation on the simplified model of the single elastic ring; S6. Compare the displacement and stress cloud diagram of the elastic ring in the elastic ring support structure with the calculation results of the simplified model of the elastic ring; S7. Compare the stiffness of the two models under different loads; S8. Analyze the parameter stiffness sensitivity of the elastic ring support structure and the simplified model, and compare it with the IS theoretical analysis; S9. Compare the calculation time of the three-dimensional model of the elastic ring support structure, the two-dimensional model of the elastic ring support structure, and the single-ring simplified model.

2. The simplified design method for elastic ring support structure stiffness design according to claim 1, characterized in that: The step S2 specifically includes: according to the given elastic ring support structure parameters, establishing a finite element model of the elastic ring support structure including two working conditions of the boss on top and the boss on the bottom, and performing finite element calculation to obtain the displacement, stress cloud diagram and stiffness value of the elastic ring support structure.

3. The simplified design method for elastic ring support structure stiffness design according to claim 2, characterized in that: The step S3 specifically includes: extracting the calculation results of the elastic ring in the elastic ring support structure according to the calculation results obtained in step S2, summarizing the deformation law of the elastic ring in the elastic ring support structure, and performing force analysis.

4. The simplified design method for elastic ring support structure stiffness design according to claim 3, characterized in that: The step S6 specifically includes: comparing the displacement and stress cloud diagrams of the elastic ring support structure in step S2 and the elastic ring in step S5 with the calculation results of the elastic ring simplified model; and determining whether the displacement deformation cloud diagram and stress cloud diagram of the elastic ring in the elastic ring support structure are consistent with the displacement cloud diagram and stress cloud diagram of the elastic ring simplified model under different working conditions.

5. The simplified design method for elastic ring support structure stiffness design according to claim 4, characterized in that: The step S7 specifically includes: calculating the stiffness of the elastic ring single-ring simplified model according to the stiffness calculation formula of the elastic ring single-ring simplified model derived in step S4, comparing it with the stiffness value of the elastic ring support structure obtained in step S2, and further comparing the stiffness of the two models under different loads.

6. The simplified design method for elastic ring support structure stiffness design according to claim 5, characterized in that: The step S8 specifically includes: analyzing the parameter stiffness sensitivity of the elastic ring support structure and the simplified model, analyzing the influence of the parameters on the stiffness of the elastic ring support structure by changing the elastic ring wall thickness, fillet radius, boss height, boss length, and boss number parameters, and calculating the stiffness values ​​of the single-ring simplified model boss-up and boss-down working conditions and the IS theoretical analytical solution within the parameter range.

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