CN111104714B - Weighing analysis method for composite material connecting rod scheme - Google Patents
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Abstract
A weighing analysis method of a composite material connecting rod scheme solves the problem that the analysis method of the composite material connecting rod scheme is lacking at present, and belongs to the field of design of aircraft structures. The invention comprises the following steps: s1, selecting a material system based on parameters of given load working conditions, rigidity constraint and external dimensions, and providing various composite material connecting rod design schemes; s2, aiming at the consideration factors of various composite material connecting rod design schemes, a balance analysis table is established, wherein the table comprises the weight of each consideration factor, the score of each design scheme about each consideration factor and the total score of all the consideration factors of each design scheme under the corresponding weight, the design scheme with the total score larger than the threshold value is selected from various schemes according to a set threshold value, and when various schemes are selected, a design model and strength analysis are established, and screening balance is carried out.
Description
Technical Field
The invention relates to a composite material connecting rod, in particular to a balance analysis method of a composite material connecting rod scheme, and belongs to the field of design of aircraft structures.
Background
The development of the aircraft mainly aims at low cost and high carrying capacity, and the aim is to solve the problem of weight reduction of the structure, and the lower connecting rod of the hanging box section is an important force transmission part of the hanging box section and is used for connecting the bottom of the hanging box section and the lower wing surface of the wing to transmit the thrust of an engine. The traditional aircrafts including B737, B777 and C919 all adopt metal materials, but with the progress of composite material technology, compared with the traditional steel connecting rod structure, if the hanging connecting rod adopts the combination of metal and composite materials, the weight can be reduced by 50-60%, and the potential economic benefit is huge. Therefore, the development of composite links is one of the key technologies for achieving the weight-reduction goal of aircraft.
At present, the research of the composite material connecting rod for the aircraft is few, and the test basis is provided for the design and the preparation of the aircraft connecting rod through systematic research such as structural simulation design, preparation technology of a composite material cylinder, connection design, verification test and the like.
Disclosure of Invention
Aiming at the lack of an analysis method of a composite material connecting rod scheme at present, the invention provides a weighing analysis method of the composite material connecting rod scheme.
The invention relates to a weighing analysis method of a composite material connecting rod scheme, which comprises the following steps:
s1, selecting a material system based on parameters of given load working conditions, rigidity constraint and external dimensions, and providing various composite material connecting rod design schemes;
s2, aiming at the consideration factors of various composite material connecting rod design schemes, a balance analysis table is established, wherein the table comprises the weight of each consideration factor, the score of each design scheme about each consideration factor and the total score of all the consideration factors of each design scheme under the corresponding weight, the design scheme with the total score larger than the threshold value is selected from various schemes according to a set threshold value, and when various schemes are selected, a design model and strength analysis are established, and screening balance is carried out.
The method has the beneficial effects that aiming at the consideration factors of various composite material connecting rod design schemes, a balance analysis table is established, each scheme has a total score according to the scores and weights of the factors, a design scheme with the total score being greater than a threshold value is selected from various schemes according to the set threshold value, and when various schemes are selected, a design model and strength analysis are established for screening and balance. The invention performs primary selection from various consideration factors, and selects a scheme for final test verification according to strength and rigidity after the primary selection.
Drawings
FIG. 1 is a schematic structural diagram of scheme 1;
FIG. 2 is a schematic structural diagram of scheme 2;
FIG. 3 is a schematic structural diagram of scheme 3;
FIG. 4 is a schematic structural diagram of scheme 4;
fig. 5 is a schematic diagram of the softening response of the bilinear model.
Detailed Description
The following description of the embodiments of the present invention will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present invention, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.
It should be noted that, without conflict, the embodiments of the present invention and features of the embodiments may be combined with each other.
The invention is further described below with reference to the drawings and specific examples, which are not intended to be limiting.
A method for weight analysis of a composite link solution of the present embodiment, the method comprising:
s1, selecting a material system based on parameters of given load working conditions, rigidity constraint and overall dimension, and providing four composite material connecting rod design schemes:
scheme 1: the connecting rod structure scheme of the composite material barrel and the metal joint are connected through bolts, as shown in figure 1;
scheme 2: an integral full composite material connecting rod structural scheme is shown in fig. 2;
scheme 3: the sleeve joint connecting rod structure scheme of the composite material cylinder body and the first metal joint is shown in fig. 3;
scheme 4: the sleeve joint connecting rod structure scheme of the composite material barrel and the second metal joint is shown in fig. 4;
s2, aiming at the consideration factors of four composite material connecting rod design schemes, a balance analysis table is established, wherein the table comprises the weight of each consideration factor, the score of each design scheme about each consideration factor and the total score of all the consideration factors of each design scheme under the corresponding weight, the design scheme with the total score larger than the threshold value is selected from multiple schemes according to a set threshold value, and when the multiple schemes are selected, a screening balance is carried out on the established design model and the strength analysis.
The rigidity, weight, difficulty in process technology, cost and the like of the above 4 schemes are combined, and are subjected to weighing analysis, and the final scoring condition of each scheme is obtained, and the results are shown in the following table 1:
table 1 trade-off analysis results for each protocol
As can be seen from the total score of each of the schemes in the above table, if the threshold value is set to 430, the total score of the scheme 2 and the scheme 3 exceeds the threshold value, and thus the intensity analysis is to be performed by using the scheme 2 and the scheme 3, and the intensity analysis method includes:
s1, simulating the composite material by adopting a bilinear model, wherein the bilinear model is the simplest and the most extensive model applied in TS rule. In fig. 5, point 1 is subjected to a tensile load in the line elasticity range, and the initial stiffness K (penalty stiffness) connects the upper and lower surfaces of the interfacial layer unit together; point 2 is the critical point of damage, and the normal stress of the interface under I-type load reaches the interlayer tensile strength; with the increase of relative displacement of the upper surface and the lower surface of the interface layer, accumulated damage occurs at the interface layer, the point 3 stress exceeds the yield point and enters a softening area, the rigidity gradually decays with the increase of relative displacement, and the area of the triangle 0-2-3 represents the energy released at the point 3; at point 4, the energy release rate reaches a critical value. When the relative displacement of the upper and lower surfaces of the interface layer is greater than a 4-point value, the interface will not be able to carry tensile or shear loads, and the damage expands as shown by 5 points. That is, at 4 points, the fracture energy of the interface will be entirely consumed. When using this softening model to simulate the delamination extension, the delamination front corresponds to a load bearing capacity of zero at 4 points, i.e. the delamination front.
The softening response illustrated in fig. 5 may be used to indicate the tensile and shear forces experienced by the interface layer and cannot be used to indicate the compressive loading experienced by the interface layer. It is generally believed that compressive loading cannot cause a layered expansion and, therefore, the compressive loading experienced by the interface layer is generally ignored.
1. When delta<δ 0 And when the load is I-type load, the linear elastic interface layer constitutive equation is as follows:
τ＝Kδ
2. when delta 0 ≤δ<δ max When, for type II loading, the constitutive equation of the interface layer can be expressed as:
τ＝(1-d)Kδ
wherein d is more than or equal to 0 and less than or equal to 1, d represents a damage accumulation coefficient at the interface, and when d=0, no damage is generated yet; when d=1, it means that the interfacial layer has been completely destroyed;
3.δ≥δ max at the time of type III loading, the penalty stiffness K degenerates to zero, the bond area is completely destroyed, and the local area loses load carrying capacity.
The constitutive model characterizes the mechanical relationship between the interfacial traction and the interfacial relative separation displacement. With the increase of the relative displacement of the upper surface and the lower surface of the interface layer, the traction force of the interface unit reaches the maximum value and then decays to zero. For independent type I, type II or type III loads, when the normal or shearing direction stress of the interface reaches the interlayer tensile or shearing strength respectively, the rigidity of the interface layer (bonding area) begins to decay, and damage is generated; when the accumulated value of the strain energy release rate of the interface layer reaches the critical type I, type II or type III fracture toughness, the stiffness of the interface layer decays to zero, and the damage begins to expand. Under type I loading, delamination front damage begins when the stress component reaches interlayer tensile strength. However, in practical engineering applications, the delamination expansion in the composite structure is always subjected to mixed form loads, and before any individual load component reaches its allowable value, the delamination has been broken. Therefore, it is necessary to set a layered damage generation criterion and a layered damage extension criterion applicable to the hybrid load form.
S2, in the bilinear model, if each stress component of the interface unit meets the requirementWhen determining layered damage generation, wherein delta z Representing normal tensile stress transferred to the interface layer; τ xz And τ yz Representing xz plane and yz shear stress, respectively; t and S represent nominal normal tensile strength and nominal shear strength, respectively;
s3, acquiring total energy G released in the damage process T When the total energy G is released T The method meets the following conditions:
and when the interface unit is not loaded, the interface unit is expanded hierarchically.
Alpha is a power factor, and the constant value is 2; g IC ，G IIC And G IIIC I, II and III fracture toughness, respectively, can be experimentally measured; g I 、G II And G III Type I, type II and type III energy released from the layered leading edge during injury, respectively, typically G IIC Equal to G IIIC ，G II Equal to G III . Total energy released during injury G T ＝G I +G II +G III 。
The research of layered damage expansion mainly adopts a fracture mechanics method, takes an energy release rate criterion as a basis, and simulates self-similar layered expansion by calculating the strain energy release rate. When the displacement reaches a certain critical value, the interface element stiffness begins to decay. When the rigidity is attenuated to zero, the interface unit fails and cannot bear load any more, and the phenomenon of layered damage expansion is macroscopically shown.
In the integral full-composite material connecting rod structure with the thickness of the cylinder body of 25mm in scheme 2, the maximum tensile displacement and the maximum compressive displacement are 1.722mm and 0.6387mm respectively, and the strength and the rigidity meet the requirements. On the basis, the thickness of the cylinder body is changed to 20mm, the maximum stretching displacement and the maximum compression displacement are 1.854mm and 0.901mm respectively, and the maximum stretching displacement and the maximum compression displacement of the all-metal connecting rod structure are 2.068mm and 1.1165mm, so that the strength and the rigidity meet the requirements. Therefore, in the two schemes, the integral full composite material connecting rod with the thickness of the cylinder body of 20mm is selected for test verification.
In the scheme 3, the sleeve connecting rod structure scheme with the thickness of the composite material cylinder body of 25mm can meet the requirements on strength and rigidity under the action of tensile load. Similarly, the thickness of the composite material cylinder body is changed from 25mm to 20mm, and the maximum stretching displacement and the maximum compression displacement of the structure are respectively 2.075mm and 1.149mm, and the maximum stretching displacement is larger than the maximum stretching displacement of the all-metal connecting rod structure, so that the strength and the rigidity do not meet the requirements. Therefore, the present embodiment selection scheme 3 performs experimental verification.
Although the invention herein has been described with reference to particular embodiments, it is to be understood that these embodiments are merely illustrative of the principles and applications of the present invention. It is therefore to be understood that numerous modifications may be made to the illustrative embodiments and that other arrangements may be devised without departing from the spirit and scope of the present invention as defined by the appended claims. It should be understood that the different dependent claims and the features described herein may be combined in ways other than as described in the original claims. It is also to be understood that features described in connection with separate embodiments may be used in other described embodiments.
Claims (3)
1. A method of weight analysis of a composite link solution, the method comprising:
s1, selecting a material system based on parameters of given load working conditions, rigidity constraint and external dimensions, and providing various composite material connecting rod design schemes;
s2, aiming at the consideration factors of various composite material connecting rod design schemes, a balance analysis table is established, wherein the table comprises the weight of each consideration factor, the score of each design scheme about each consideration factor and the total score of all the consideration factors of each design scheme under the corresponding weight, the design scheme with the total score larger than the threshold value is selected from various schemes according to a set threshold value, and when various schemes are selected, a design model and strength analysis are established for the scheme, and screening balance is carried out;
the considerations include manufacturing cost, process feasibility, design feasibility, strength analysis method maturity, functional requirements, assembly difficulty, maintainability, weight, tooling mold and experimental verification;
in the step S2, the intensity analysis process is as follows:
s21, simulating a composite material by adopting a bilinear model, wherein the composite material is used for representing the mechanical relationship between each stress of an interface unit and relative separation displacement of an interface under three loads, and the three loads comprise a type I load, a type II load and a type III load; wherein the tensile stress delta < delta 0 Type I load when delta 0 ≤δ＜δ max The type II load is represented when the tensile stress delta is more than or equal to delta max And represents type III load; delta 0 Tensile stress, delta, indicative of the onset of damage to the composite material max Indicating the maximum bearing stress of the composite material;
s22, in the bilinear model, if each stress component of the interface unit meetsWhen determining layered damage generation, wherein delta z Representing normal tensile stress transferred to the interface layer; τ xz And τ yz Representing xz plane and yz shear stress, respectively; t and S represent nominal normal tensile strength and nominal shear strength, respectively;
s23, acquiring total energy G released in the damage process T When the total energy G is released T The method meets the following conditions:
when the interface unit is not loaded, the interface unit is expanded in a layered manner;
alpha is a power factor, G IC ，G IIC And G IIIC I, II and type III fracture toughness, respectively; g I 、G II And G III Type I, type II and type III energy released from layered front edge during injury process respectively, total energy G released during injury process T ＝G I +G II +G III 。
2. The method for analyzing the balance of the composite material connecting rod scheme according to claim 1, wherein in S1, the linear elastic interface layer constitutive equation of the composite material with the type I load is:
τ＝Kδ
where τ represents the intensity and K represents the penalty stiffness;
the constitutive equation of the interfacial layer of the type II loaded composite is:
τ＝(1-d)Kδ
wherein d is more than or equal to 0 and less than or equal to 1, d represents a damage accumulation coefficient at the interface, and when d=0, no damage is generated yet; when d=1, it means that the interfacial layer has been completely destroyed;
the penalty stiffness K of the type III load is degraded to zero, the bond area is completely destroyed, and the local area loses load carrying capacity.
3. The method for analyzing the balance of the composite material connecting rod scheme according to claim 2, wherein in the step S2, for type I, type II or type III loads, when the normal stress of the interface reaches the tensile strength between layers or the stress in the shearing direction reaches the shearing strength, the stiffness of the interface layer begins to decay, and damage is generated; when the accumulated value of the strain energy release rate of the interface layer reaches the critical type I, type II or type III fracture toughness, the stiffness of the interface layer decays to zero, and the damage begins to expand.
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Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101853320A (en) * | 2010-05-17 | 2010-10-06 | 北京航空航天大学 | Fuzzy comprehensive evaluation method suitable for aircraft structure corrosion damage |
| CN103366070A (en) * | 2013-08-01 | 2013-10-23 | 北京航空航天大学 | Method for designing composite material beam for helicopter and fixed-wing aircraft |
| CN104571048A (en) * | 2015-01-12 | 2015-04-29 | 南京航空航天大学 | Method for evaluating machining technology of airplane structure parts based on value engineering and machining characteristics |
| CN106153459A (en) * | 2015-04-02 | 2016-11-23 | 陕西飞机工业（集团）有限公司 | A kind of metal material method of evaluating performance based on aircaft configuration selection |
| CN107274490A (en) * | 2017-06-08 | 2017-10-20 | 河海大学 | A kind of free form surface structural form creation method for considering material damage and reinforcing bar effect |
| CN107832560A (en) * | 2017-11-29 | 2018-03-23 | 北京航空航天大学 | A kind of full SiC ceramic matrix composite material Multi-fasteners joint structural failure analysis method based on asymptotic damage model |
| CN108153981A (en) * | 2017-12-26 | 2018-06-12 | 中航沈飞民用飞机有限责任公司 | A kind of composite material fuselage Material Stiffened Panel Post-Buckling Analysis of Structures method based on finite element analysis |
| CN110232255A (en) * | 2019-06-24 | 2019-09-13 | 南京航空航天大学 | A kind of method of carbon fibre reinforced composite drilling axial force prediction |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20070232883A1 (en) * | 2006-02-15 | 2007-10-04 | Ilegbusi Olusegun J | Systems and methods for determining plaque vulnerability to rupture |
| FR2963070B1 (en) * | 2010-07-23 | 2014-02-14 | Airbus Operations Sas | AIRCRAFT COMPRISING A ROD COMPRISING A PART OF COMPOSITE MATERIAL |
-
2019
- 2019-12-24 CN CN201911349634.7A patent/CN111104714B/en active Active
Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101853320A (en) * | 2010-05-17 | 2010-10-06 | 北京航空航天大学 | Fuzzy comprehensive evaluation method suitable for aircraft structure corrosion damage |
| CN103366070A (en) * | 2013-08-01 | 2013-10-23 | 北京航空航天大学 | Method for designing composite material beam for helicopter and fixed-wing aircraft |
| CN104571048A (en) * | 2015-01-12 | 2015-04-29 | 南京航空航天大学 | Method for evaluating machining technology of airplane structure parts based on value engineering and machining characteristics |
| CN106153459A (en) * | 2015-04-02 | 2016-11-23 | 陕西飞机工业（集团）有限公司 | A kind of metal material method of evaluating performance based on aircaft configuration selection |
| CN107274490A (en) * | 2017-06-08 | 2017-10-20 | 河海大学 | A kind of free form surface structural form creation method for considering material damage and reinforcing bar effect |
| CN107832560A (en) * | 2017-11-29 | 2018-03-23 | 北京航空航天大学 | A kind of full SiC ceramic matrix composite material Multi-fasteners joint structural failure analysis method based on asymptotic damage model |
| CN108153981A (en) * | 2017-12-26 | 2018-06-12 | 中航沈飞民用飞机有限责任公司 | A kind of composite material fuselage Material Stiffened Panel Post-Buckling Analysis of Structures method based on finite element analysis |
| CN110232255A (en) * | 2019-06-24 | 2019-09-13 | 南京航空航天大学 | A kind of method of carbon fibre reinforced composite drilling axial force prediction |
Non-Patent Citations (1)
| Title |
|---|
| 张园园.基于综合评分法的沥青混凝土配合比优选.《路桥工程》.2015,第770、784页. * |
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