CN106202652A - The lightweight topological method of product and shredder cutterhead - Google Patents

Abstract

The invention discloses a kind of product light-weighted topological optimization algorithm, The present invention gives a parameters optimization constrained procedure commonly used, rational percentage by volume and iterations rather than artificial trial can be immediately arrived at by theoretical algorithm, shorten the design cycle, advantage for this week method of large and complex structure is more prominent, the method can adjust parameter according to the different of design structure precision, such as initial percentage by volume, percentage by volume increment, and value, institute in this way most of Topology Algorithm are all suitable for.The invention also discloses a kind of shredder cutterhead, sword is torn up including what disk body and fixing with described disk body was connected, described disk body includes that annular connection dish and multiple Yu described connection dish are integrally formed and are distributed on the tool rest connecting disk ring week, and before and after described disk body, two sides are respectively correspondingly provided with groove.

Description

The lightweight topological method of product and shredder cutterhead

Technical field

The present invention relates to technical field of mechanical design, particularly relate to lightweight topological method and the shredder of a kind of product Cutterhead.

Background technology

The purpose of structure optimization is to make the structure designed more economical from material, and from structure, the distribution of power is more reasonable.Its Content contains structural dimension optimization, Shape optimization and topological optimization, and topological optimization is side even more important in structure optimization Face, the improvement of structural topology can be substantially improved the performance of structure or alleviate the weight of structure, bringing direct economic benefit, because of This choice structure topology optimization problem, as research direction, has great realistic meaning.At present, Topology Optimization Method has uniformly Change method (homogenization method), density variable method, Varying-thickness method (variable thickness method), gradually Enter method (evoluti onary structural optimization (ESO) method) and BESO method etc., wherein BESO side Method is to be improved on the basis of ESO method, and BESO method can not only delete unit can also recovery unit.ESO method Proposed by Xie and Steven the earliest, mainly make final remaining material reach set by constantly reducing material Constraints.BESO method is proposed by Querin et al the earliest, is the improvement to ESO method, by deleting or extensive Multiple unit makes final volume meet constraints, and it is the unit not having stress less that this method terminates the condition of iteration, In this way can ensure that the rigidity of structure, and the physical dimension of topologies can clearly be calculated.But This method is a kind of evolution method, so its iterations is more, computational efficiency is inefficient compared with SIMP method, this Outward, although Tanskanen discusses the theoretical basis of ESO, but its convergence has not been established, and this also makes Obtain BESO method instability and mistake easily occurs.

Topological optimization plays an important role in terms of lightweight product, and shredder cutter diameter is 450mm, and thickness is 50mm, carries out topological optimization to it and makes its lightweight can increase whole tearing up in the case of tearing up usefulness not reducing shredder The life-span of machine, and improve the stress of main shaft, thus reduce the energy consumption of shredder.

Summary of the invention

It is an object of the invention to for technological deficiency present in prior art, and the lightweight topology of a kind of product is provided Method.

It is an object of the invention to disclose and a kind of utilize what described product lightweight topological method prepared to tear up machine knife Dish.

Be the technical scheme is that by realizing the purpose of the present invention

A kind of product light-weighted topology design method, comprises the following steps,

1) to Modeling in Product and by given design section limited grid discretization setup unit property value and initial Boundary condition and initial load；

2) carry out finite element analysis and obtain unit and the sensitivity data of node；

3) minima a of a percentage by volume is set；

4) at whole design section, node sensitivity data is carried out submissiveization；I.e. the Sensitirity va1ue of each unit again It is ranked up, determines to delete unit by sensitivity, big not the deleting of sensitivity,

5) according to formulaCalculate current sensitivity degrees of data and the meansigma methods of a upper iteration step sensitivity data, And preserve to following iteration step use, wherein α_iReferring to the sensitivity of i-th unit, k is current iterations；

6) target volume that following iteration walks is determined；An iteration will delete some unit, and successive ignition is close to target Volume；

7) property value of unit is redefined；Utilize new cell attribute value amendment design having as next step iteration Finite element analysis model；

8) 2 are repeated)-7) step, until reaching predetermined target volume and meeting convergence criterion, i.e. reach to set The volume requirement of small size percent a,

9) on the basis of first initial volume percent, increase the percentage by volume that value is m carry out counting for the second time Calculation repeats 3)-8), until meeting ε_rLess than 0.1；

10) by step 9) draw topology percentage by volume and iterations input BESO model in and obtain final Topological structure.

The present invention gives a parameters optimization constrained procedure commonly used, conjunction can be immediately arrived at by theoretical algorithm The percentage by volume of reason rather than artificial trial, shorten the design cycle, for the advantage of this week method of large and complex structure More prominent, the method can adjust parameter, such as initial percentage by volume a, volume hundred according to the different of design structure precision Fractional increments, and ε_rValue, institute in this way most of Topology Algorithm are all suitable for.

Described step 2)-9) computational methods be:

$\underset{x}{Min}C\left(x\right)=F^{T}U=U^{T}KU---\left(1\right)$

$\begin{array}{ccccc}Subjectto:& X=\left\{x_e\right\},x_e=1& or& x_{\min }& \∀e=1,\mathrm{\Λ},N\end{array}---\left(2\right)$

F=KU (3)

$V\left(X\right)=\underset{X}{\Σ}{x}_e{v}_e=V^{*}---\left(4\right)$

$|V_{r^{\′}}^{*}-V^{*}|\≤0.0001---\left(5\right)$

T=r'(6)

$e=\frac{\left|{\mathrm{\Σ}}_{i=1}^N(C_{k-i+1}-C_{k-t-i+1})\right|}{{\mathrm{\Σ}}_{i=1}^N{C}_{K-i+1}}\≤\mathrm{\τ}---\left(7\right)$

V^*=fV₀ (8)

Wherein r=1,2,3, Λ, N (9)

F=a+rm (10)

F and U represents load vector and displacement vector respectively；C is flexibility；x_eBeing the e design variable, solid element is 1, Dummy cell takes 0.001；N is total number of unit；K is Bulk stiffness matrix；F is percentage by volume；M is that percentage by volume increases Amount, it is substantially relevant with design accuracy, and precision its value the highest is the least；R is calculation times；ε_rRepresent be the r time calculating time The change of two adjacent volume percentage difference values and the ratio of maximum Flexibility Difference；What r' represented is changing when meeting formula (5) Generation number, t represents the iterations meeting Structural Design Requirement；What k represented is current iterations；I represents element number； What a represented is an initial minimum volume percent.

Preferably, described product is the cutterhead of shredder, The present invention gives the adjacent body being applicable to shredder cutterhead The difference of long-pending percent and the ratio 0.1 of maximum Flexibility Difference, at difference and the ratio of maximum Flexibility Difference of adjacent percentage by volume During less than 0.1, the structure of shredder cutterhead can reduce volume under conditions of meeting rigidity to greatest extent, reaches green raw The effect produced.

Preferably, in described step 9) in utilize Python program that percentage by volume and iterations are assigned to BESO mould Type is to improve BESO efficiency.

A kind of shredder cutterhead, including disk body with fix the sword that tears up being connected with described disk body, described disk body includes Annular connection dish and multiple Yu described connection dish are integrally formed and are distributed on the tool rest connecting disk ring week, described disk body Front and back two sides are respectively correspondingly provided with groove.

The connection dish that the root of described tool rest is corresponding is formed with through hole.

For regular polygon hole to be in transmission connection with corresponding polygon shaft in the middle part of described connection dish.

Described through hole is circular.

Described tool rest is 6.

Described tool rest be connected dish arrange in the same plane, described tool rest triangular in shape and with the radial direction being connected dish Keeping angle, be formed with joint face inside the outer end of tool rest, the back of described tool rest is arc.

Compared with prior art, the invention has the beneficial effects as follows:

The present invention gives a parameters optimization constrained procedure commonly used, conjunction can be immediately arrived at by theoretical algorithm The percentage by volume of reason rather than artificial trial, shorten the design cycle, for the advantage of this week method of large and complex structure More prominent, the method can adjust parameter, such as initial percentage by volume a, volume hundred according to the different of design structure precision Mark increments, and ε_rValue, institute in this way most of Topology Algorithm are all suitable for.

Accompanying drawing explanation

Fig. 1 show the cutterhead modeling schematic diagram of the present invention；

Fig. 2 show the structural representation after topological optimization；

Fig. 3 show percentage by volume and deformation quantity graph of a relation.

Detailed description of the invention

Below in conjunction with the drawings and specific embodiments, the present invention is described in further detail.Should be appreciated that described herein Specific embodiment only in order to explain the present invention, be not intended to limit the present invention.

The present invention will be described further with below equation for detailed description of the invention.

$\underset{x}{Min}C\left(x\right)=F^{T}U=U^{T}KU---\left(1\right)$

$\begin{array}{ccccc}Subjectto:& X=\left\{x_e\right\},x_e=1& or& x_{\min }& \∀e=1,\mathrm{\Λ},N\end{array}---\left(2\right)$

F=KU (3)

$V\left(X\right)=\underset{X}{\Σ}{x}_e{v}_e=V^{*}---\left(4\right)$

$|V_{r^{\′}}^{*}-V^{*}|\≤0.0001---\left(5\right)$

T=r'(6)

$e=\frac{\left|{\mathrm{\Σ}}_{i=1}^N(C_{k-i+1}-C_{k-t-i+1})\right|}{{\mathrm{\Σ}}_{i=1}^N{C}_{K-i+1}}\≤\mathrm{\τ}---\left(7\right)$

V^*=fV₀ (8)

Wherein r=1,2,3, Λ, n (9)

F=a+rm (10)

F and U represents load vector and displacement vector respectively；C is flexibility；x_eBeing the e design variable, solid element is 1, Dummy cell takes 0.001；N is total number of unit；K is Bulk stiffness matrix；F is percentage by volume；M is that percentage by volume increases Amount, it is relevant with design accuracy, and precision its value the highest is the least；R is calculation times；ε is two adjacent volume percentage difference values Change and the ratio of maximum Flexibility Difference；ε_rRepresent be the r time calculate time two adjacent volume percentage difference values change and The ratio of maximum Flexibility Difference；What r' represented is the iterations when meeting formula (5), and t represents and meets Structural Design Requirement Iterations；What k represented is current iterations；I represents element number；What a represented is an initial minimum volume hundred Mark.

Specifically, comprise the following steps

1, utilizing finite element software ABAQUS to be modeled cutterhead, the size of cutterhead is 50mm with reference to the thickness of cutterhead, The material of cutterhead is that its design parameter of 42CrMo is shown in Table 1,

Table 1 cutterhead material parameter

Constraints is fixation cutter head inner ring, and inside triangle indication part is geometrical constraint part as shown in Figure 1, outward What portion's arrow represented is loading section, and the size of load draws according to the dynamic analog of shredder, and shredder tears up Automobile Plate Process, the material of Automobile Plate is 6111 aluminium alloys, and thickness is 8mm, analyze during shredder tears up the stress shape of cutterhead Condition, selects the load that the every a part of stress of cutterhead is maximum, uses maximum load to load FEM (finite element) model, to guarantee topology The reliability of optimum results, magnitude of load specifically gives in the following table.

This model is carried out stress and strain model, is 10182 unit by model partition, 13055 nodes, use C3D8R mono- Element type, 8 node linear hexahedral elements, reduce integration, hourglass control.

2, operation program draws parameters optimization

Execution equation (6)-(8) utilizing Python program constantly to circulate draw one so that constitutionally stable iteration Number of times, circulation solves (9), and (10) two formulas can draw the percentage by volume of optimization, and shown below is with shredder cutterhead As a example by draw the data of flexibility, program can stop 65% in percentage by volume, and following data is only for explanation difference rate of change Start flexibility change to start to diminish less than 0.1, can show that optimum percentage by volume is 65% according to formula (10), i.e. have satisfied Enough meet volume during rigidity minimum simultaneously, thus reach light-weighted purpose, in order to verification expression (10) correctness we adjust Go out the value of each percentage by volume deformation quantity, as shown in following table and Fig. 3, find the change of deformation quantity when percentage by volume is 65% Melting the change beginning to diminish explanation rigidity to reduce, illustrating that percentage by volume is when 65% is suitable.

3 topological optimizations realize

This algorithm adds the constraint to parameters optimization based on BESO Topology Optimization Method, and this algorithm is easy to write journey Sequence, and have the good compatibility with ABAQUS software, utilize Python program to realize this calculating, wherein volume constraint letter VolFrac, iterations iter represent, import this program in ABAQUS/CAE module, i.e. obtain final optimization topology Structure.

The invention provides a kind of new topological optimization algorithm, this algorithm adds based on BESO Topology Optimization Method Constraint to parameter, reduces blindness and the error manually taking Selection parameter, thus improves the efficiency of topological optimization, accelerates to optimize Process, and reduce the mistake occurred during optimization, increase the reliability of design.

Simultaneously as its a kind of concrete application, devising a kind of new car shredder cutterhead, it is than the body of original cutterhead Long-pending reduce 23%, and demonstrate its rigidity and intensity theoretically all in tolerance band.

As in figure 2 it is shown, the cutterhead of the present invention includes that what annular disk body 1 and fixing with described disk body was connected tears up sword, Described disk body 1 includes that annular connection dish 10 and multiple Yu described connection dish are integrally formed and are distributed on connection disk ring week Tool rest 11, before and after described disk body, two sides are respectively correspondingly provided with groove 12, corresponding at the root of described tool rest 11 Connection dish on be formed with circular through hole 13.

The cutterhead of the present invention, front and back, two sides are respectively arranged with the groove of the formula of emptying, i.e. shape on connection dish and tool rest Become a communication type groove, be effectively reduced overall volume, and combine force analysis, tool rest root less for stress is corresponding Connection dish on offer through hole, reduce further cutterhead weight, and arranging of through hole facilitate locating and machining, effectively prevents The appearance of unbalance dynamic phenomenon occurs.

Specifically, described tool rest is to be that regular polygon hole is with corresponding in the middle part of 6 described connection dishes

Polygon shaft, as hexagonal shaft is in transmission connection, uses tool rest and axle sleeve to set formula mode, and stable transmission is reliable and keeps in repair Maintenance is convenient.

Wherein, tearing up the more preferable cutting angle of sword for ease of providing, described tool rest is arranged on same plane with being connected dish In, described tool rest is triangular in shape and keeps angle with the radial direction being connected dish, i.e. tool rest is obliquely installed the most in one direction, Being formed with joint face 14 inside the outer end of tool rest, the described sword that tears up is fixedly installed on joint face, utilizes the most inside Sword is torn up in the joint face fixed installation tilted, and when tearing up sword stress, radial shape diminishes, and is effectively improved service life.

The above is only the preferred embodiment of the present invention, it is noted that for the common skill of the art For art personnel, under the premise without departing from the principles of the invention, it is also possible to make some improvements and modifications, these improvements and modifications Also should be regarded as protection scope of the present invention.

Claims (9)

1. a product light-weighted topology design method, it is characterised in that comprise the following steps,

1) to Modeling in Product and by given design section limited grid discretization setup unit property value and initial boundary Condition and initial load；

2) carry out finite element analysis and obtain unit and the sensitivity data of node；

3) minima a of a percentage by volume is set；

4) at whole design section, node sensitivity data is carried out submissiveization；

5) according to formulaCalculate current sensitivity degrees of data and the meansigma methods of a upper iteration step sensitivity data, and preserve Use to following iteration step, wherein α_iReferring to the sensitivity of i-th unit, k is current iterations；

6) target volume that following iteration walks is determined；

7) property value of unit is redefined；Utilize new cell attribute value amendment design the finite element as next step iteration Analyze model；

8) 2 are repeated)-7) step, until reaching predetermined target volume and meeting convergence criterion；

9) increase on the basis of a upper percentage by volume value m carry out calculating for the second time as new percentage by volume Repeat 3)-8), until meeting ε_rLess than 0.1, m is the percentage by volume increment set；

10) by step 9) percentage by volume of topology that draws and iterations again input in BESO in mastery routine and obtain Whole topological structure.

2. lightweight topological method as claimed in claim 1, it is characterised in that described step 2)-9) computational methods be:

$\underset{x}{\mathrm{Min}}C\left(x\right)=F^{T}U=U^T\mathrm{KU}---\left(1\right)$

$\begin{array}{ccccc}Subjectto:& X=\left\{x_e\right\},x_e=1& or& x_{\min }& \∀e=1,\mathrm{\Λ},N\end{array}---\left(2\right)$

F=KU (3)

$V\left(X\right)=\underset{X}{\Σ}{x}_e{v}_e=V^{*}---\left(4\right)$

$|V_{r^{\′}}^{*}-V^{*}|\≤0.0001---\left(5\right)$

T=r'(6)

$e=\frac{\left|{\mathrm{\Σ}}_{i=1}^N(C_{k-i+1}-C_{k-t-i+1})\right|}{{\mathrm{\Σ}}_{i=1}^N{C}_{K-i+1}}\≤\mathrm{\τ}---\left(7\right)$

Wherein r=1,2,3, Λ, N (9)

F=a+rm (10)

F and U represents load vector and displacement vector respectively；C is flexibility；x_eBeing the e design variable, solid element is 1, empty single Unit takes 0.001；N is total number of unit；K is Bulk stiffness matrix；F is percentage by volume；M is that the percentage by volume set increases Amount；R is calculation times；ε_rRepresent is the change of two adjacent volume percentage difference values during the r time calculating and maximum flexibility The ratio of difference；What r' represented is the iterations when meeting formula (5), and t represents the iterations meeting Structural Design Requirement； What k represented is current iterations；I represents element number；What a represented is an initial minimum volume percent, wherein Volume constraint equation is (4) formula；Object function (1) ensure that the balance of total；(6) formula calculates and meets the iteration time required Number, the iteration time when its value is that the percentage by volume infinite approach target of structure amasss percent after iteration；(7) formula is convergence standard Then；(8)-(10) constrain percentage by volume.

3. lightweight topological method as claimed in claim 1, it is characterised in that utilize in described step (6)-(10) Percentage by volume and iterations are assigned to BESO model to improve BESO efficiency by Python program.

4. the shredder cutterhead obtained by the lightweight topological method described in any one of claim 1-3, it is characterised in that Including disk body with fix the sword that tears up being connected with described disk body, described disk body includes annular connection dish and multiple and institute The connection dish stated is integrally formed and is distributed on the tool rest connecting disk ring week, and before and after described disk body, two sides are respectively correspondingly arranged Fluted.

5. shredder cutterhead as claimed in claim 4, it is characterised in that on the connection dish that the root of described tool rest is corresponding It is formed with through hole.

6. shredder cutterhead as claimed in claim 4, it is characterised in that be regular polygon hole in the middle part of described connection dish with Corresponding polygon shaft is in transmission connection.

7. shredder cutterhead as claimed in claim 5, it is characterised in that described through hole is circular.

8. shredder cutterhead as claimed in claim 4, it is characterised in that described tool rest is 6.

9. shredder cutterhead as claimed in claim 4, it is characterised in that described tool rest is arranged on same plane with being connected dish In, described tool rest is triangular in shape and keeps angle with the radial direction being connected dish, is formed with joint face inside the outer end of tool rest, The back of described tool rest is arc.