CN113962024A - Outer diameter simulation and trunk harness outer diameter estimation method for aircraft harness - Google Patents

Outer diameter simulation and trunk harness outer diameter estimation method for aircraft harness Download PDF

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CN113962024A
CN113962024A CN202111243730.0A CN202111243730A CN113962024A CN 113962024 A CN113962024 A CN 113962024A CN 202111243730 A CN202111243730 A CN 202111243730A CN 113962024 A CN113962024 A CN 113962024A
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CN113962024B (en
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于洋
王述东
蔡瑶琦
谢云
魏来
郑博
汤炜晨
陈博
涂军安
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Chengdu Aircraft Industrial Group Co Ltd
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Abstract

The invention discloses an outer diameter simulation and trunk wire harness outer diameter estimation method of an airplane wire harness, which is applied to the technical field of airplane wire harness checking, and the outer diameter simulation method comprises the following steps: the method for estimating the outer diameter of the trunk wiring harness comprises the following steps: s1, obtaining the cable size specification, the cable number and the cable arrangement mode of the branch wiring harness, and establishing a simulation model; s2, dividing the cable into N circle layers from inside to outside in the radial direction of the branch wire harness, and dividing the circumscribed circle of each circle layer; s3, adjusting the arrangement of the ith layer of cable according to the radius of the circumscribed circle of the ith layer of cable; s4, accumulating the radius of the branch cable and the thickness of the outer-layer protective sleeve of the branch wiring harness and multiplying the sum by 2; the problem that the estimation of the outer diameter of the wire harness in the prior art is inaccurate and the estimation result is generally not suitable can be solved, the wire harnesses with the same and different cable sizes can be quickly estimated, the outer diameter of the wire harness can be determined more accurately, the result is closer to a real measured value, and therefore the accuracy and the production efficiency of the production size of the wire harness are improved.

Description

Outer diameter simulation and trunk harness outer diameter estimation method for aircraft harness
Technical Field
The invention relates to the technical field of aircraft harness checking, in particular to an outer diameter simulation and trunk harness outer diameter estimation method of an aircraft harness.
Background
The pencil comprises the cable that the quantity is inequality, the diameter is different on the aircraft, at aircraft wiring in-process, adopts the cable clamp as main support piece usually, and the selection of clamp is mainly based on with the external diameter (diameter) of pencil, and the clamp selects too big pencil fixed insecure, and the clamp selects the easy clamp of undersize and hinders the cable and make its damage, and above circumstances all can lead to electric connector's reliability to receive the influence. The conventional wire harness outer diameter estimation method comprises an equivalent square method and a reference formula given in a navigation mark. The equivalent square method is to add the areas of the equivalent square cables to estimate the diameter of the wire harness, and the estimated value is generally smaller than the measured value. The result calculated according to the navigation mark reference formula is too large to be used directly. The hoop selection method at the present stage is completely selected by design experience, the phenomenon that a hoop fixed by a wire harness section is generally not suitable exists, and when a new machine is developed, due to the fact that a method for verifying the correctness of the selection of the designed hoop is lacked by technologists, the problem that the size of the hoop in a digital-analog model is not suitable cannot be found during process inspection, and the problem is transmitted to the site. The way of finding and solving problems by trial and error seriously reduces the production efficiency and improves the production cost. In addition, the diameter of the wire harness has guiding significance for designing a wire harness passage and an opening frame, so that the accurate estimation of the diameter of the wire harness is very important, and a method for simulating the outer diameter of a wire harness section needs to be researched. A
Disclosure of Invention
The invention aims to solve the problems of inaccurate and generally unsuitable estimation of the outer diameter of the wire harness in the prior art, and provides a method for simulating the outer diameter of the aircraft wire harness and estimating the outer diameter of a main wire harness, which can accurately determine the outer diameter of the wire harness, thereby improving the production size accuracy and production efficiency of the wire harness, improving the wiring efficiency and indicating the design of a wire harness passage and an opening frame.
In order to achieve the above purpose, the invention provides the following technical scheme:
an outer diameter simulation method of an aircraft wire harness comprises the following steps:
s1, acquiring the size and the number of cables of the branch wire harness, the arrangement mode of the cables in the branch wire harness closed body, and establishing a simulation model;
s2, dividing the cable into N circle layers from inside to outside in the radial direction of the branch wire harness according to the arrangement mode of the cable in the simulation model, wherein N is a positive integer, and dividing the circumscribed circle of each circle layer of the cable on the cross section of the branch wire harness; the circumscribed circle of each layer of cable is circumscribed to the plurality of cables of each layer, and the circumscribed circle of each layer of cable surrounds all the cables of the layer and is circumscribed to the cables of the layer as much as possible;
s3, according to the radius r of the circumscribed circle of the ith layer of cableiI is more than or equal to 1 and less than or equal to N, the arrangement of the ith layer of cables is adjusted to ensure that each circle of layer of cables is in a perfect circle or a region close to the perfect circle;
s4, the radius of the branch cable and the thickness l of the outer layer protective sleeve of the branch wiring harnessDefendAdding and multiplying by 2 to obtain the outer diameter D of the branch wire harnessBranch standWherein, the radius of the branch cable is the radius r of the circumscribed circle of the Nth layer cableN。
The simulation model is established by collecting the specification, the number and the arrangement data of the branch wire harnesses, and after the cables are bundled, the diameter is influenced by the number of cables, the specification and the arrangement mode of the cables, the arrangement modes of the cables are various and difficult to directly estimate, therefore, the simulation model is divided and adjusted by simulating the internal structure of a real airplane branch wire harness, the difficulty of estimating the outer diameter of the branch wire harness can be reduced, the internal structure of the simulation model is divided into a plurality of circles of layers, each circle of layer is a layered structure with uniformly distributed cables, each layer of cable is normalized to be a perfect circle by adjusting the cross section of the cable, the model is simplified and is convenient to calculate, the outer diameter of the branch wire harness is estimated finally, the outer diameter of the branch wire harness can be estimated accurately, the estimated value is close to the actual measured value, and the accuracy is high.
In a preferred embodiment of the present invention, in step S3, when the number of cables in the ith layer in the model needs to be adjusted, the radius variation Δ R of the ith layer is:
Figure BDA0003320182680000031
wherein r is the radius of the cable, and n is the number of cables on the ith layer.
By calculating the radius of the circumscribed circle of the cable on the ith layer, under the condition that the number of cables differs by one, the radius change of the ith layer added with one cable is obtained through the phase difference, and the variable quantity between adjacent ring layers is obtained, so that whether adjustment is needed or not is judged according to the variable quantity.
In a preferred embodiment of the present invention, when the number of cables in the ith layer in the model is adjusted, the radius variation Δ R of the ith layer is:
ΔR≈0.31r
wherein r is the radius of the cable.
The radius variation of the circumscribed circle of the ith layer is obtained by taking different values, and the approximate value of the radius variation is used as the standard of the variation delta R to judge the radius increase value of any cable added in any circle layer.
In a preferred embodiment of the present invention, in the step S3, when the number of cables in each turn layer is adjusted, the specific steps include:
s31, calculating the radius difference of all adjacent circle layers in the simulation model, wherein the radius difference is deltaii+1＝Ri+1-Ri；
S32, determining Deltaii+1Whether the radius of the branch cable is within the range of 2r +/-0.31 r or not, if so, adjusting the number of cables of each circle layer is not needed, and the radius of the branch cable is the radius of an external circle of the cable of the outermost circle layer;
s33, if maxi|Δii+1If the-2 r is more than 0.31r, updating the number of cables at the i-th layer and the i + 1-th layer until the number of cables at all the circle layers is updated, wherein the updating mode is as follows:
if Δii+12r is more than 0, the number of cables in the ith layer is updated to niUpdating the number of the (i + 1) th layer cables to ni+1-1；
If Δii+12r is less than 0, the number of the cables of the ith layer is updated to niUpdating the number of the (i) th +1 st layer cables to ni+1+1。
Whether adjustment is carried out or not is judged by calculating the radius difference of adjacent circle layers in the simulation model, the mode of updating the number of cables of the (i + 1) th layer is determined by comparing the radius difference with 2r +/-0.31 r, the operation process can be simplified, the number of cables can be updated by visual comparison, the mode of adjusting the cables is in a quantification mode, operation is easy, the basis of updating conditions is established, and estimation is more accurate.
In the preferred embodiment of the present invention, when the number n of the cables is larger than the predetermined numberi<And 7, keeping the number of the cables on the ith layer, not adjusting, and regarding all the cables in the circumscribed circle of the ith layer as one layer of cable.
All the cables with the number less than 7 are regarded as one layer, so that the calculation process is simplified, and when the number of the cables is small, the circle layers are easily and obviously divided, the number of the circle layers is stable, and the arrangement of the circle layers is influenced by adjusting the cables, so that the steps are omitted by simplifying the calculation, and meanwhile, the estimation accuracy is not influenced.
In a preferred embodiment of the present invention, when the cable dimensions are the same, in step S3, the radius of the circumscribed circle of the i-th cable layer is determined by the following formula:
Figure BDA0003320182680000041
wherein i is the number of divided cable layers; riThe radius of the circumscribed circle of the ith layer of cable; r is the radius of the cable, niIndicating the number of cables of the i-th layer.
The calculation can be carried out to the branch pencil that cable size specification is the same, can carry out circumscribed radius's calculation to the cable of different circle layers, extensive applicability.
In a preferred embodiment of the present invention, when the cable sizes are different, in step S3, the radius of the circumscribed circle of the i-th layer cable is determined by the following formula:
Figure BDA0003320182680000051
wherein i ∈ Z+The number of the cable layers is positive integer; riRepresents the radius of the circumscribed circle of the ith layer cable; n isiIndicating the number of ith layer cables; r iseqIs the equivalent radius of the cable.
The calculation can be carried out to the branch pencil that the cable size specification is different, can carry out the calculation of circumscribed circle radius to the cable on different circle layers, extensive applicability.
In a preferred embodiment of the present invention, the equivalent radius of the cable is:
Figure BDA0003320182680000052
wherein J belongs to J and represents the specification of the cable, J is the estimated cable specification number contained in the branch cable bundle, rjDenotes the radius, s, of the cable of the jth specificationjIndicates the number of cables of the jth gauge,
Figure BDA0003320182680000053
representing pre-estimated branchesThe total number of cables contained in the harness.
The radius of the cable is equivalent to the average cable specification, so that the model is simplified, and calculation is convenient.
The method for estimating the outer diameter of the main wire harness of the aircraft wire harness adopts the outer diameter simulation method of the aircraft wire harness, and comprises the following steps of:
SS1, calculating the radius of different branch cables by an outer diameter simulation method
Figure BDA0003320182680000061
k is the serial number of the branch wire harness;
SS2, establishing the sectional area S of the main cableMaster and slaveCross section area of branch line
Figure BDA0003320182680000062
The area relation of (1):
Figure BDA0003320182680000063
wherein K is the branch number of the main wiring harness, namely the total number of the branch wiring harnesses,
Figure BDA0003320182680000064
the sectional area of the branch cable in the branch wire harness with the serial number k;
SS3 combined with area formula of circle for dividing the radius of branch cable of different branch wire harnesses
Figure BDA0003320182680000065
Substituting the area relation expression, and transforming to obtain the radius R of the trunk cable of the trunk wiring harnessMaster and slave；
SS4, radius R of trunk cable of trunk harnessMaster and slaveAnd the thickness L of the outer protective sleeve of the trunk wiring harnessDefendAdding and multiplying by 2 to obtain the outer diameter D of the trunk line bundleMaster and slave；
Wherein the order of steps SS1 and SS2 may be interchanged.
By calculating the radius of the branch wire harness, the calculation of the radius of the main wire harness is simplified into the calculation of the mean value, and the outer diameter of the main wire harness can be comprehensively reflected for the branch wire harnesses with different specifications.
In the preferred embodiment of the present invention, the outer diameter D of the trunk harness is obtained through the above-mentioned step SS4Master and slaveComprises the following steps:
Figure BDA0003320182680000066
wherein L isDefendThe thickness of the outer layer protective sleeve of the main wiring harness.
The external diameter of the main wire harness is obtained by combining the branch wire harness and the main wire harness through a circular area formula, and the external diameter is directly substituted into the radius value of the branch wire harness to obtain a conclusion.
Compared with the prior art, the invention has the beneficial effects that:
1. the method comprises the steps of establishing a simulation model consistent with a branch wire harness through an outer diameter simulation method, dividing the internal structure of the simulation model into a plurality of circles of layers, regulating each layer of cable to be a perfect circle on the cross section of the cable, simplifying the model, facilitating calculation, carrying out outer diameter simulation calculation on the branch wire harness, and finally estimating the outer diameter of the branch wire harness.
2. By the main harness outer diameter estimation method, the outer diameters of the main harnesses can be comprehensively reflected for the branch harnesses with the same or different specifications, the outer diameters of the main harnesses are obtained through area formula conversion, the outer diameters of the main harnesses can be obtained by directly substituting the radius values of the branch harnesses, and the main harness outer diameters are closer to a real measured value.
Description of the drawings:
FIG. 1 is a step diagram of an outer diameter simulation method according to embodiment 1 of the present invention;
FIG. 2 is a diagram of a simulation model according to embodiment 1 of the present invention;
FIG. 3 is a circled division diagram of a simulation model of embodiment 1 of the present invention;
FIG. 4 is a schematic view of a branch harness according to embodiment 1 of the present invention;
FIG. 5 is a diagram of a simulation model according to embodiment 2 of the present invention;
FIG. 6 is a circled division diagram of a simulation model according to embodiment 2 of the present invention;
FIG. 7 is a graph showing the variation of the radius Δ R of the ith layer of coils in example 2;
FIG. 8 is a diagram of a simulation model according to embodiment 3 of the present invention;
fig. 9 is a step diagram of a trunk harness outer diameter estimation method of an aircraft harness according to embodiments 4 and 5 of the present invention;
the labels in the figure are: 1-branch line beam and 2-main line beam.
Detailed Description
The present invention will be described in further detail with reference to test examples and specific embodiments. It should be understood that the scope of the above-described subject matter is not limited to the following examples, and any techniques implemented based on the disclosure of the present invention are within the scope of the present invention.
Example 1
Referring to fig. 1, the present embodiment discloses an outer diameter simulation method for an aircraft wire harness, which may adopt the same method for different aircraft wire harnesses, wherein the aircraft wire harness includes a trunk wire harness 2 and branch wire harnesses 1, the branch wire harnesses 1 are a plurality of wires, cables, or optical cables, wire groups that are arranged and can be installed or disassembled as one assembly, and also include a connector assembly terminated by the branch wire harnesses 1, the branch wire harnesses 1 are internally wrapped by a plurality of cables, and the plurality of branch wire harnesses 1 are bundled together to form an aircraft wire harness, the trunk wire harness 2 is a portion where paths of the plurality of branch wire harnesses 1 bundled together overlap, and the outer diameter simulation method is to estimate the outer diameter of the branch wire harnesses 1, and specifically includes the following steps:
s1, acquiring the cable size specification and the cable number of the branch wiring harness 1 and the arrangement mode of cables in the branch wiring harness 1 enclosure, and establishing a simulation model, wherein cables with different specifications can be inserted into the enclosure, pinholes in the enclosure are not necessarily full, partial pinholes are allowed to be vacant, and the cable arrangement mode in the branch wiring harness 1 generally determines the cable arrangement mode in the enclosure; in this embodiment, cables with the same specification are arranged, please refer to fig. 2, the circular components and structures are cables, and all the cables are arranged in the closed body, which is the cross-sectional structure of the simulation model in fig. 2.
S2, please refer to fig. 3, according to the arrangement of the cables in the simulation model, the cables are divided into N circle layers from inside to outside in the radial direction of the branch harness 1, N is a positive integer greater than or equal to 1, the nth layer is the outermost layer of the harness, and the circumscribed circle of each circle layer of the cable is divided on the cross section of the branch harness 1, in this embodiment, the branch harness 1 is divided into 5 layers from inside to outside, and the outermost layer of the simulation model is the 5 th layer; dividing 5 layers, namely requiring that the circumscribed circle of each layer of cable is circumscribed to a plurality of cables of each layer, namely, the plurality of cables of each layer of cable are all inscribed in the circumscribed circle, the plurality of cables refer to a plurality of cables, the circumscribed circle of each layer of cable surrounds all the cables of the layer, the circumscribed circle is circumscribed to the cables of the layer as much as possible, and all the cables of each layer can not be ensured to be inscribed in the circumscribed circle of the layer in practice; however, it is necessary to cut the cables above 1/2, even above 2/3, into the circumscribed circle of the layer, the branch cables are all the cables contained in the branch harness 1, the diameter of the branch cables is determined by the circle filled by the branches, the diameter of the branch cables is determined by the number of the outermost cables, and the circumscribed circle of the branch cables is the circumscribed circle of the outermost cables.
S3, according to the circumscribed radius R of the ith layer of cableiI is more than or equal to 1 and less than or equal to 5, the arrangement of the ith layer of cables is adjusted to ensure that the circumscribed circle of each circle of layer of cables is a perfect circle or a nearly perfect circle, and after the cables are bundled into a beam, the diameter is influenced by the number, specifications and arrangement modes of the cables, the arrangement modes of the cables are various and difficult to estimate directly, so that the simulation model is divided and adjusted by simulating the internal structure of a real airplane branch wire harness 1; in this embodiment, there are 5 layers of cables, and after dividing the 5 layers of cables, the cable arrangement of each layer is adjusted in such a way that a small number, generally one or two, of the cables on the ith layer are adjusted to adjacent layers, the adjustment way is manual adjustment, and the cable positions are moved to re-form cables on different layers, so that a certain layer of cables is replaced by a new cableThe number of the cables on the layers is increased or decreased, so that the circumscribed circles formed by the cables on each layer are concentric as much as possible, the radius difference between the circumscribed circles on adjacent layers is equal as much as possible, the difference value is equal to the diameter of one cable, and 5 concentric circles with different diameters are formed.
S4, the radius of the branch cable and the thickness l of the outer layer protective sleeve of the branch wiring harness 1DefendAdding up and multiplying by 2 to obtain the outer diameter D of the branch wire harness 1Branch standWherein, the radius of the branch cable is the radius R of the circumscribed circle of the Nth layer cableNThe branch cable is an overall structure formed by combining 5 layers of cables, and the radius of the branch cable is the radius of an outer diameter circle of the outermost layer of cable, in this embodiment, the radius is the radius R of a circumscribed circle of the 5 th layer of cable5On the basis of the radius, the thickness of the outer-layer protective sleeve of the branch wiring harness 1 is the radius of the whole branch wiring harness 1.
The outer diameter simulation method can reduce the difficulty of estimating the outer diameter of the branch wire harness 1, the internal structure of the simulation model is divided into a plurality of circles of layers, each circle of layer is a layered structure with uniformly distributed cables, each layer of cable is normalized to be a perfect circle by adjusting the cross section of the cable, the model is simplified and is convenient to calculate, then the outer diameter simulation calculation of the branch wire harness 1 is carried out, the outer diameter of the branch wire harness 1 is finally estimated, the outer diameter of the branch wire harness 1 can be accurately estimated, the estimated value is close to the actual measured value, and the accuracy is high.
Example 2
Referring to fig. 5, the present embodiment is substantially the same as embodiment 1, except that: the present embodiment is a simulation of an aircraft harness composed of cables with the same size, and the step S3 is further refined and improved.
The embodiment discloses an outer diameter simulation method of an aircraft wire harness, which is used for estimating the outer diameter of a branch wire harness 1 and specifically comprises the following steps, wherein the steps S1, S2 and S4 are the same as those in the embodiment 1, and the difference is that step S3.
And S1, acquiring the size specification and the number of the cables of the branch wiring harness 1 and the arrangement mode of the cables in the closed body of the branch wiring harness 1, and establishing a simulation model.
S2, please refer to fig. 6, in the simulation model, the cable is arranged in a hexagonal prism shape, according to the arrangement of the cable in the simulation model, the cable is divided into 4 circle layers from inside to outside in the radial direction of the branch harness 1, and the cross section of the branch harness 1 is divided into an outer circle of each circle layer of the cable.
S3, according to the circumscribed radius R of the ith layer of cableiI is more than or equal to 1 and less than or equal to 4, the arrangement of the ith layer of cable is adjusted to ensure that each circle of layer of cable is in a perfect circle or an area close to the perfect circle; the radius of the circumscribed circle of the ith layer of cable has two calculation modes, namely the situation that the cable size and specification are the same and the situation that the cable size and specification are different, and the wire harness with the same cable size and specification is adopted in the embodiment.
When the cable size specification is the same, the radius of the circumscribed circle of the ith layer of cable is calculated and determined by the following formula (1):
Figure BDA0003320182680000111
wherein i is the number of divided cable layers; riThe radius of the circumscribed circle of the ith layer of cable; r is the radius of the cable, niIndicating the number of cables of the i-th layer.
For example, when the cable radius is 1mm, the radius of the circumscribed circle of the innermost cable, i.e. the radius of the circumscribed circle of the 1 st layer, is:
Figure BDA0003320182680000112
determining the radius R of the circumscribed circle of each layer of cableiThen according to the radius R of the circumscribed circleiThe change of (2) is to adjust the arrangement of the cable on the ith layer, and to adjust the cable on the (i + 1) th layer, namely to move the cable from the (i + 1) th layer when adjusting the cable on the ith layer, so as to increase the number of cables on the ith layer or the (i + 1) th layer or reduce the number of cables.
When the number of cables on each circle of layer is adjusted, the method specifically comprises the following steps:
s31, calculating the radius difference of all adjacent circle layers in the simulation model, wherein the radius difference is deltaii+1＝Ri+1-Ri；
S32, determining Deltaii+1Whether the radius of the branch cable is within the range of 2r +/-0.31 r or not, if so, adjusting the number of cables of each circle layer is not needed, and the radius of the branch cable is the radius of an external circle of the cable of the outermost circle layer;
s33, if maxi|Δii+1If the-2 r is more than 0.31r, updating the number of cables at the i-th layer and the i + 1-th layer until the number of cables at all the circle layers is updated, wherein the updating mode is as follows:
if Δii+12r is more than 0, the number of cables in the ith layer is updated to niUpdating the number of the (i + 1) th layer cables to ni+1-1；
If Δii+12r is less than 0, the number of the cables of the ith layer is updated to niUpdating the number of the (i) th +1 st layer cables to ni+1+1。
When the ith layer of cable is adjusted, the number of cables on the ith layer needs to be considered, and when the number of cables n is equal to the number of cables on the ith layeri<And 7, keeping the number of the cables on the ith layer, not adjusting, and regarding all the cables in the circumscribed circle of the ith layer as one layer of cable.
All the cables with the number less than 7 are regarded as one layer, so that the calculation process is simplified, and when the number of the cables is small, the circle layers are easily and obviously divided, the number of the circle layers is stable, and the arrangement of the circle layers is influenced by adjusting the cables, so that the steps are omitted by simplifying the calculation, and meanwhile, the estimation accuracy is not influenced.
Whether adjustment is carried out or not is judged by calculating the radius difference of adjacent circle layers in the simulation model, the mode of updating the number of cables of the (i + 1) th layer is determined by comparing the radius difference with 2r +/-0.31 r, the operation process can be simplified, the number of cables can be updated by visual comparison, the mode of adjusting the cables is in a quantification mode, operation is easy, the basis of updating conditions is established, and estimation is more accurate.
When the number of cables on the ith layer in the model is adjusted, the radius variation Δ R of the ith layer is formula 2 when one cable is added:
Figure BDA0003320182680000121
wherein r is the radius of the cable, and n is the number of cables on the ith layer.
By calculating the radius of the circumscribed circle of the cable on the ith layer, when the number of cables differs by one, the radius change of the ith layer after adding one cable is obtained through the phase difference, the variation between adjacent circle layers is obtained, so that whether adjustment is needed or not is judged by taking the variation as a basis, namely, the radius variation delta R is a basis for whether adjustment is needed or not, and the variation is used intuitively for convenience, in the method steps S32-S33, a comparison object of the radius difference of the adjacent circle layers is determined, so that the judgment is directly carried out, and the determination of the comparison object is obtained through the following steps:
when the number of cables on the ith layer in the model is adjusted, the radius variation delta R of the ith layer is as follows when one cable is added:
ΔR≈0.31r
wherein r is the radius of the cable.
Referring to fig. 7, it can be seen from fig. 7 that, for each additional cable, the variation trend of the circle layer radius variation Δ R is plotted, the abscissa is the number of the circle layer cables, and the ordinate is the circle layer radius variation, and it can be seen that when the number of the cables increases to the 7 th cable, the variation of the circle layer radius is almost constant, where Δ R is about 0.3165 when R is 1; when R ≈ 2, Δ R ≈ 0.6325; when R is 3, Δ R ≈ 0.9495; calculating to obtain the variation of the radius of the ring layer of each cable with 1 added radius r as 0.31r, and determining the radius difference delta between adjacent ring layers in steps S32-S33ii+1According to the method, the variation of the radius of the circumscribed circle of the ith layer is obtained by taking different values, and the approximate value of the variation is used as the standard of the variation delta R to judge the radius increase value of any cable in any circle layer.
S4, after the ith layer of cable is adjusted, the adjusted simulation model can be estimated, the outer diameter of the branch wiring harness 1 can be estimated, and the radius of the branch cable and the thickness l of the outer layer protective sleeve of the branch wiring harness 1 are adjustedDefendAdding up and multiplying by 2 to obtain the outer diameter D of the branch wire harness 1Branch standReference toEquation 3:
Dbranch stand＝2(RBranch stand+lDefend) (3)
Wherein the radius R of the branch cableBranch standIs the circumscribed circle radius R of the Nth layer cableN，lDefendThe thickness of the outer protective sleeve of the branch wiring harness 1.
Example 3
This embodiment is substantially the same as embodiment 2, except that this embodiment is calculated for the case where the cable size specification is different.
Referring to fig. 8, when the cable sizes are different, in step S3, the radius of the circumscribed circle of the ith layer of cable is determined by the following formula 4:
Figure BDA0003320182680000141
wherein i ∈ Z+The number of the cable layers is positive integer; riRepresents the radius of the circumscribed circle of the ith layer cable; n isiIndicating the number of ith layer cables; r iseqIs the equivalent radius of the cable.
The step can be used for calculating the branch wire harnesses 1 with different cable sizes and specifications, and calculating the radius of the external circle of the cable with different circle layers, so that the applicability is wide.
In the above calculation process, the equivalent radius of the cable needs to be obtained first, and the equivalent radius of the cable is as in formula 5:
Figure BDA0003320182680000142
wherein J belongs to J and represents the specification of the cable, J is the estimated cable specification number contained in the branch cable bundle 1, rjDenotes the radius, s, of the cable of the jth specificationjIndicates the number of cables of the jth gauge,
Figure BDA0003320182680000143
represents the total number of cables contained in the pre-estimated branch harness 1; calculating reqThen substituting the radius into a radius calculation formula 4 of each circle layer to obtain a preliminary calculation result of the radius of each circle layer, subsequently determining a final cable arrangement mode according to a cable number adjusting method of each circle layer with the same radius in embodiment 2, and finally estimating the number of the outermost cables and the radius of the branch cables, thereby obtaining the outer diameter R of the branch wiring harness 1Branch stand(ii) a The radius of the cable is equivalent to the average cable specification, so that the model is simplified, and calculation is convenient.
Example 4
The embodiment provides a method for estimating the outer diameter of a trunk harness 2 of an aircraft harness, which adopts the method for simulating the outer diameter of the aircraft harness in the embodiment 1 or 2, and calculates the outer diameter of the harness with the same cable size and specification.
Referring to fig. 9, the method for estimating the outer diameter of the trunk harness 2 includes the following steps:
SS1, calculating the radius of different branch cables by the outer diameter simulation method
Figure BDA0003320182680000151
k is the number of the branch bundle 1, wherein the radius of the different branch cables
Figure BDA0003320182680000152
For R calculated by example 1 or 2Branch standSince the present embodiment is directed to wire harnesses having the same cable size, the radii of different branch cables are all equal;
the cable dimensions selected for this example are as follows:
TABLE 1 Main Cable dimension Specification Table
Figure BDA0003320182680000153
SS2, please refer to fig. 4, since the main cable is a part with the same path of the branch cables at both ends, the diameter of the main harness 2 inside it is related to the diameters of the different branch harnesses 1, and based on symmetry, the space occupied by all the cables of the main harness 2 in the radial direction is the different branch harnesses at one end of the main harness 21 in the radial direction, considering that the diameters of different branch harnesses 1 at two ends of a main harness 2 are different, and in order to obtain an average value and reduce the influence of individual branch harnesses 1, the space occupied by the main harness 2 in the radial direction of a cable is half of the sum of the spaces occupied by the branch harnesses 1 at two ends in the radial direction, and the sectional area S of the main cable is establishedMaster and slaveCross-sectional area of branch wire harness 1
Figure BDA0003320182680000154
Equation 6:
Figure BDA0003320182680000155
wherein K is the branch number of the main wiring harness 2, namely the total number of the branch wiring harnesses 1,
Figure BDA0003320182680000161
the sectional area of the branch cable inside the branch wire harness 1 with the serial number k; by calculating the radius of the branch wire harness 1, the calculation of the radius of the main wire harness 2 is simplified into the calculation of the mean value, and the outer diameter of the main wire harness 2 can be comprehensively reflected for the branch wire harnesses 1 with different specifications; the order of steps S1 and S2 may be interchanged.
SS3, area formula of combination circle, and radius of branch cable of different branch wiring harnesses 1
Figure BDA0003320182680000162
Substituting the area relation expression to obtain the radius R of the trunk cable of the trunk wiring harness 2 through transformationMaster and slave；
SS4, main cable radius R of main harness 2Master and slaveAnd the thickness L of the outer protective sleeve of the trunk wiring harness 2DefendAdding up and multiplying by 2 to obtain the outer diameter D of the trunk wiring harness 2Master and slaveThe following equation 7:
Figure BDA0003320182680000163
wherein L isDefendFor outer protection of trunk wiring harness 2The thickness of the sleeve.
Through the area formula of circle, combine branch pencil 1 and trunk pencil 2, obtain the external diameter of trunk pencil 2, directly substitute the radius value of branch pencil 1 and alright draw the conclusion.
The data in Table 1 were calculated through steps SS2 and SS3 as follows: outer diameter D of trunk harness 2Master and slave6.72+0.4mm is 7.12mm, and the outer diameter of the trunk harness 2 subjected to the equivalent square diameter simulation is 6.04mm, and the actually measured value of the outer diameter of the trunk harness 2 is 7.2mm, so the method for estimating the outer diameter of the trunk harness 2 adopted by the embodiment is closer to the actually measured value.
Example 5
The embodiment discloses an outer diameter estimation method of a main wiring harness 2 of an aircraft wiring harness, which adopts the same outer diameter estimation method of the main wiring harness 2 as that of the embodiment 4, and is different in that the embodiment is based on a branch wiring harness 1 simulation method in the embodiment 1 or 3, and the embodiment calculates for wiring harnesses with different cable size specifications.
Referring to fig. 9, the method for estimating the outer diameter of the trunk harness 2 includes the following steps:
SS1, calculating the radius of different branch cables by the outer diameter simulation method
Figure BDA0003320182680000171
The cable dimensions selected for this example are as follows:
TABLE 2 Main Cable dimension specification table
Figure BDA0003320182680000172
SS2, establishing the sectional area S of the main cableMaster and slaveCross-sectional area of branch wire harness 1
Figure BDA0003320182680000173
The area relation of (1);
SS3, area formula of combination circle, and radius of branch cable of different branch wiring harnesses 1
Figure BDA0003320182680000174
Substituting the area relation expression to obtain the radius R of the trunk cable of the trunk wiring harness 2 through transformationMaster and slave；
SS4, main cable radius R of main harness 2Master and slaveAnd the thickness L of the outer protective sleeve of the trunk wiring harness 2DefendAdding up and multiplying by 2 to obtain the outer diameter D of the trunk wiring harness 2Master and slave；
The above steps are all the same as those in example 4;
according to the data in Table 2, the calculation results from steps SS2 and SS3 are: outer diameter D of trunk harness 2Master and slave12.65+0.3mm 12.95mm, the outer diameter of the trunk harness 2 subjected to the equivalent square diameter simulation is 9.49mm, and the actually measured value of the outer diameter of the trunk harness 2 is 12.6mm, so that the method for estimating the outer diameter of the trunk harness 2 adopted in the embodiment is closer to the actually measured value.
The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents and improvements made within the spirit and principle of the present invention are intended to be included within the scope of the present invention.

Claims (10)

1. An outer diameter simulation method of an aircraft wire harness is characterized by comprising the following steps:
s1, acquiring the size and the number of cables of the branch wire harness, the arrangement mode of the cables in the branch wire harness closed body, and establishing a simulation model;
s2, dividing the cable into N circle layers from inside to outside in the radial direction of the branch wire harness according to the arrangement mode of the cable in the simulation model, wherein N is a positive integer, and dividing the circumscribed circle of each circle layer of the cable on the cross section of the branch wire harness;
s3, according to the circumscribed radius R of the ith layer of cableiI is more than or equal to 1 and less than or equal to N, the arrangement of the ith layer of cables is adjusted to ensure that each circle of layer of cables is in a perfect circle or a region close to the perfect circle;
s4, the radius of the branch cable and the thickness l of the outer layer protective sleeve of the branch wiring harnessDefendAdding and multiplying by 2 to obtain branch wire harnessOuter diameter D ofBranch standWherein, the radius of the branch cable is the radius R of the circumscribed circle of the Nth layer cableN。
2. The method for simulating the outer diameter of the aircraft wire harness according to claim 1, wherein in step S3, when the number of cables in the ith layer in the model needs to be adjusted, the radius change Δ R of the ith layer is:
Figure FDA0003320182670000011
wherein r is the radius of the cable, and n is the number of cables on the ith layer.
3. The method for simulating the outer diameter of the aircraft wire harness according to claim 2, wherein when the number of cables on the ith layer in the model is adjusted, the radius change Δ R of the ith layer is:
ΔR≈0.31r
wherein r is the radius of the cable.
4. The method for simulating the outer diameter of the aircraft wire harness according to claim 3, wherein in the step S3, when the number of cables in each circle of layers is adjusted, the method specifically comprises the following steps:
s31, calculating the radius difference of all adjacent circle layers in the simulation model, wherein the radius difference is deltaii+1=Ri+1-Ri；
S32, determining Deltaii+1Whether the radius of the branch cable is within the range of 2r +/-0.31 r or not, if so, adjusting the number of cables of each circle layer is not needed, and the radius of the branch cable is the radius of an external circle of the cable of the outermost circle layer;
s33, if maxi|Δii+1If the-2 r is more than 0.31r, updating the number of cables at the i-th layer and the i + 1-th layer until the number of cables at all the circle layers is updated, wherein the updating mode is as follows:
if Δii+12r > 0, then the ith layerUpdating the number of cables to niUpdating the number of the (i + 1) th layer cables to ni+1-1；
If Δii+12r is less than 0, the number of the cables of the ith layer is updated to niUpdating the number of the (i) th +1 st layer cables to ni+1+1。
5. The method for simulating the outer diameter of an aircraft wire harness as claimed in claim 4, wherein the number of cables n isi<And 7, keeping the number of the cables on the ith layer, not adjusting, and regarding all the cables in the circumscribed circle of the ith layer as one layer of cable.
6. The method for simulating the outer diameter of the aircraft wire harness according to claim 1, wherein the cable dimensions are the same, and in step S3, the radius of the circumscribed circle of the ith layer of cable is determined by calculating according to the following formula:
Figure FDA0003320182670000021
wherein i is the number of divided cable layers; riThe radius of the circumscribed circle of the ith layer of cable; r is the radius of the cable, niIndicating the number of cables of the i-th layer.
7. The method for simulating the outer diameter of the aircraft wire harness according to claim 1, wherein when the cable sizes are different, in step S3, the radius of the circumscribed circle of the i-th layer cable is determined by calculation according to the following formula:
Figure FDA0003320182670000031
wherein i ∈ Z+The number of the cable layers is positive integer; riRepresents the radius of the circumscribed circle of the ith layer cable; n isiIndicating the number of ith layer cables; r iseqIs the equivalent radius of the cable.
8. The method of simulating an outer diameter of an aircraft harness as claimed in claim 7, wherein the equivalent radius of the cable is:
Figure FDA0003320182670000032
wherein J belongs to J and represents the specification of the cable, J is the estimated cable specification number contained in the branch cable bundle, rjDenotes the radius, s, of the cable of the jth specificationjIndicates the number of cables of the jth gauge,
Figure FDA0003320182670000033
representing the total number of cables contained in the pre-estimated branch line bundle.
9. A method for estimating the outer diameter of a trunk harness of an aircraft harness, which is characterized in that the method for simulating the outer diameter of the aircraft harness according to any one of claims 1 to 8 is adopted, and comprises the following steps:
SS1, calculating the radius of different branch cables by an outer diameter simulation method
Figure FDA0003320182670000034
k is the serial number of the branch wire harness;
SS2, establishing the sectional area S of the main cableMaster and slaveCross section area of branch line
Figure FDA0003320182670000035
The area relation of (1):
Figure FDA0003320182670000036
wherein K is the branch number of the main wiring harness, namely the total number of the branch wiring harnesses,
Figure FDA0003320182670000041
a branch harness with serial number kThe cross-sectional area of the internal branch cable;
SS3 combined with area formula of circle for dividing the radius of branch cable of different branch wire harnesses
Figure FDA0003320182670000042
Substituting the area relational expression into the area relational expression to transform to obtain the radius R of the trunk cable of the trunk wiring harnessMaster and slave；
SS4, radius R of trunk cable of trunk harnessMaster and slaveAnd the thickness L of the outer protective sleeve of the trunk wiring harnessDefendAdding and multiplying by 2 to obtain the outer diameter D of the trunk line bundleMaster and slave；
Wherein the order of steps S1 and S2 may be interchanged.
10. The method for estimating the outer diameter of a trunk wire harness of an aircraft according to claim 9, wherein the outer diameter D of the trunk wire harness is obtained by step SS4Master and slaveComprises the following steps:
Figure FDA0003320182670000043
wherein L isDefendThe thickness of the outer layer protective sleeve of the main wiring harness.
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