CN106250646A - A kind of Optimization Design of tower barrel of wind generating set flange - Google Patents

Abstract

The invention belongs to wind-driven generator technical group field, disclose the Optimization Design of a kind of tower barrel of wind generating set flange, basic theories based on Mathematical Planning, the mechanical model that annular flange connects is reduced to single hop Flange joint, with the structural parameters of tower drum flange as design variable, the failure mode of four kinds of theories of plasticity, spanner space and the bolt hole back gauge of bolt a size of about restraint condition, set up the mathematical programming model using the cumulative volume of flange and bolt as object function, optimized algorithm is finally used to solve the flange connection that the cumulative volume obtaining making flange and bolt is minimum.It is the lightest and meet the optimized flange connection of four kinds of failure modes of flange Plastic Design that application the method obtains quality.This method is easily programmed realization, it is possible to reduce the amount of calculation of designer, improves rapidity and the accuracy of design.

Description

A kind of Optimization Design of tower barrel of wind generating set flange

Technical field

The present invention relates to wind-driven generator technical group field, particularly relate to the optimization of a kind of tower barrel of wind generating set flange Method for designing.

Background technology

MW class wind turbine group tower many employings drum type brake steel tower at present.Drum type brake steel tower is generally divided into Multistage, every section of tower end welded flange, tower is combined by each section of flange with bolts.The operation of wind-driven generator Bad environments, stand under load is complicated, and the safety that the security relationship of tower structure to complete machine is run, therefore the design of tower drum flange becomes Obtain extremely important.

For tower drum flange, elastic design is guarded very much, and can increase construction cost.Therefore in GL specification Regulation tower drum flange design calculate use plastic joint theory, i.e. Petersens method (failure mode A and failure mode B) and Seidel method (failure mode D and failure mode E).The method is applicable to L-type and T-flange.Petersen method and Seidel method Annular flange is connected and is reduced to single hop flange link model, as long as it is shown in figure 1, the bolt of single hop model and flange are in the limit Do not lost efficacy under the effect of load, then annular flange connection also will meet requirement of strength.Single hop flange attachment force model is carried out Bold simplification, as in figure 2 it is shown, its calculated results is substantially consistent with experimental data thus is widely used. The connection of mecystasis lower flange has 4 kinds of failure modes, as it is shown on figure 3, the ultimate tension at tower wall is necessarily less than and results from The tensile bearing capacity of four kinds of failure modes.

Use said method to carry out flange design, in the case of known load, tower wall thickness and tower external diameter, need not Disconnected trial amendment flange size parameter (parameter a, b, n, t as shown in Figure 4) and diameter of bolt d carry out tentative calculation and meet four kinds of inefficacies Pattern.This amount of calculation for designer is very big, and final design result is it cannot be guaranteed that flange connection Quality the gentliest change.

Summary of the invention

Embodiments of the invention provide the Optimization Design of a kind of tower barrel of wind generating set flange, to realize tower method The quality of flange connection structure is the gentliest changed, it is proposed that tower drum flange method for designing based on Mathematical Planning, it is easy to programming realization, permissible Quick and precisely obtain design result.

For reaching above-mentioned purpose, embodiments of the invention adopt the following technical scheme that and are achieved.

The Optimization Design of a kind of tower barrel of wind generating set flange, comprises annular flange, described ring in described tower The cross section of shape flange is L-type, and described annular flange is linked in sequence by multiple single hop flanges and forms, and described method includes walking as follows Rapid:

Step 1, determines the ultimate bending moment that tower outer diameter D t, tower wall thickness s and annular flange kernel of section are subject to M, and set the diameter d of bolt；

Step 2, by distance a of annular flange inside edge to bolt axis, distance b of bolt axis to barrel center, ring Shape flange thickness t, bolt quantity n as design variable, build object function G:

$G=\mathrm{\π}\·({\mathrm{Dt}}^2-{\left(Dt-2\·a-2\·b-s\right)}^2)\·\frac{t}{4}+n\·d^2$

Wherein, object function G represents the cumulative volume of single hop flange and bolt, n ＞ 0, t ＞ 0；

Step 3, the ultimate bending moment being subject to according to described tower outer diameter D t, tower wall thickness s, annular flange kernel of section M and bolt quantity n calculates single hop flange tension；

Step 4, sets and solves described bound for objective function, and described constraints includes: described single hop flange is subject to The pulling force arrived meets spanner spatial design rule less than the tensile bearing capacity of single hop flange, spanner bulk during assembling bolt Model, bolt hole back gauge size meets bolt hole back gauge design specification；

Step 5, according to described object function and constraints, sets up mathematical programming model, solves described Mathematical Planning Model, obtains the one group design variable minimum so that described object function, and single hop flange corresponding to this group design variable and The cumulative volume of bolt；

Step 6, resets the diameter d of bolt, and is repeated in step 2 to step 5, until obtaining organizing design change more Amount, and organize single hop flange corresponding to design variable and the cumulative volume of bolt more；

Step 7, the one group of design choosing the cumulative volume so that single hop flange and bolt in many group design variables minimum becomes Measure the structural parameters as single hop Flange joint.

The feature of technical solution of the present invention and being further improved to:

(1) step 3 specifically includes:

Count according to ultimate bending moment M that described tower outer diameter D t, tower wall thickness s and annular flange kernel of section are subject to Calculation single hop flange tension Z:

$Z=\frac{4\·M}{n\·D_s}$

Wherein, n is bolt quantity, D_sFor tower barrel central diameter, D_s=Dt-s.

(2), in step 4, single hop flange tension specifically includes less than the tensile bearing capacity of single hop flange:

(4a) under failure mode A, the tensile bearing capacity Z of single hop flange_A=F_{T, Rd}, F_{T, Rd}Tension for single bolt is held Load power:

$F_{t,Rd}=\frac{K\·A_S\·f_{ub}}{{\mathrm{\γ}}_M}$

Wherein, K is partial safety factor, A_sFor bolt stress area, γ_MFor material factor, f_ubFor bolt ultimate tensile；

Failure mode A to be met, single hop flange tension Z is necessarily less than the anti-of under failure mode A single hop flange Draw bearing capacity, i.e. meet Z_AV-Z ＞ 0, v are reduction coefficient, v ＜ 1；

(4b) under failure mode B, the tensile bearing capacity of single hop flangeWherein, losing efficacy Bending drag M of barrel under Mode B_{Pl, 3b}:

$M_{pl,3b}=\min \left\{\begin{array}{c}\[1-{\left(\frac{Z_B}{c\·s\·f_{ys}}\right)}^2\]\·\frac{c\·s^2\·f_{ys}}{4}\\ \[\sqrt{1-{\left(\frac{Z_B}{c\·t\·f_{yd}/\sqrt{3}}\right)}^2}\]\·\frac{c\·t^2\·f_{yd}}{4}\end{array}\right.$

Wherein,C is the approximate width of single hop flange model, f_ysAllowable for tower barrel Yield strength, f_ydYield strength allowable for annular flange；

Failure mode B to be met, single hop flange tension Z is necessarily less than the anti-of under failure mode B single hop flange Draw bearing capacity, i.e. meet Z_BV-Z ＞ 0, v are reduction coefficient, v ＜ 1；

(4c) under failure mode D, the tensile bearing capacity of single hop flangeWherein, at bolt hole The addition bend drag M ' that single hop flanges bend drag and bolt bias produce_{Pl, 2}:

${M^{\′}}_{pl,2}=\frac{c^{\′}\·t^2\·f_{yd}}{4}+\frac{F_{t,Rd}}{2}\·\frac{d_S+d_B}{4}$

Bending drag M of barrel under failure mode D_{Pl, 3d}:

$M_{pl,3d}=\min \left\{\begin{array}{c}\[1-{\left(\frac{Z_D}{c\·s\·f_{ys}}\right)}^2\]\·\frac{c\·s^2\·f_{ys}}{4}\\ \[\sqrt{1-{\left(\frac{Z_D}{c\·t\·f_{yd}/\sqrt{3}}\right)}^2}\]\·\frac{c\·t^2\·f_{yd}}{4}\end{array}\right.$

C '=c-d_B

b_D=b

Wherein, c ' is the approximate width of the single hop flange model after reduction at bolt hole, d_BFor the diameter of bolt hole, d_SFor Washer outer diameter, b_DDistance for bolt axis to barrel plastic hinge；

Failure mode D to be met, single hop flange tension Z is necessarily less than the anti-of under failure mode D single hop flange Draw bearing capacity, i.e. meet Z_DV-Z ＞ 0, v are reduction coefficient, v ＜ 1；

(4d) under failure mode E, the tensile bearing capacity of single hop flangeWherein, at inefficacy mould Bending drag M of barrel under formula E_{Pl, 3e}:

$M_{pl,3e}=\min \left\{\begin{array}{c}\[1-{\left(\frac{Z_E}{c\·s\·f_{ys}}\right)}^2\]\·\frac{c\·s^2\·f_{ys}}{4}\\ \[\sqrt{1-{\left(\frac{Z_E}{c\·t\·f_{yd}/\sqrt{3}}\right)}^2}\]\·\frac{c\·t^2\·f_{yd}}{4}\end{array}\right.$

$b_E=b-\frac{d_S+d_B}{4}$

$M_{pl,2}=\frac{c\·t^2\·f_{yd}}{4}$

M_{Pl, 2}For single hop flanges bend drag, b_EDistance for gasket width center to plastic hinge；

Failure mode E to be met, single hop flange tension Z is necessarily less than the anti-of under failure mode E single hop flange Draw bearing capacity, i.e. meet Z_EV-Z ＞ 0, v are reduction coefficient, v ＜ 1.

(3), in step 4, spanner bulk during assembling bolt meets spanner spatial design specification, particularly as follows:

Obtain according to the design specification that JB/ZQ 4005-2006 specifies: minimum between tower annular flange connecting bolt Circumferential distance A2 and minimum spacing E1 of bolt distance barrel, thus obtain following constraints:

(Dt-2·b-s)·π/n≥0

b-s/2-E1≥0

Wherein, Dt represents tower external diameter, and s represents tower wall thickness, and b represents the bolt axis distance to barrel center, n Representing bolt quantity, E1 represents the minimum spacing of bolt distance barrel.

(4), in step 4, bolt hole back gauge size meets bolt hole back gauge design specification, particularly as follows:

According to the regulation of EN 1993-1-8 [4], bolt hole center to structure edge distance more than or equal to bolt aperture 1.2 times, thus obtain following constraints:

a-1.2·d_B≥0

Wherein, a represents the annular flange inside edge distance to bolt axis, d_BRepresent the diameter of bolt hole.

(5), in step 5, according to described object function and constraints, mathematical programming model is set up as follows:

Object function:

Constraints: Z_iV-Z ＞ 0 (i=A, B, D, E)

(Dt-2·b-s)·π/n≥0

b-s/2-E1≥0

a-1.2·d_B≥0

N ＞ 0

T ＞ 0

Wherein, Dt represents tower external diameter, and s represents tower wall thickness, and M represents the limit that annular flange kernel of section is subject to Moment of flexure, d represents the diameter of bolt, and a represents the annular flange inside edge distance to bolt axis, and b represents that bolt axis is to barrel The distance at center, t represents annular flange thickness, and n represents bolt quantity, Z_i(i=A, B, C, D) represents at failure mode A, B, C Or the tensile bearing capacity of single hop flange under D, Z represents single hop flange tension, and v is reduction coefficient, and E1 represents bolt distance The minimum spacing of barrel, d_BRepresent diameter of bolt hole.

Present invention basic theories based on Mathematical Planning, is reduced to single hop flange even by the mechanical model that annular flange connects Connect, with the structural parameters of tower drum flange as design variable, the failure mode of four kinds of theories of plasticity, the spanner space of bolt and bolt Hole back gauge a size of about restraints condition, sets up the mathematical programming model using the cumulative volume of flange and bolt as object function, finally Optimized algorithm is used to solve the flange connection that the cumulative volume obtaining making flange and bolt is minimum.Application the method obtains quality The lightest and meet the optimized flange connection of four kinds of failure modes of flange Plastic Design.This method is easily programmed realization, The amount of calculation of designer can be reduced, improve rapidity and the accuracy of design.

Accompanying drawing explanation

In order to be illustrated more clearly that the embodiment of the present invention or technical scheme of the prior art, below will be to embodiment or existing In having technology to describe, the required accompanying drawing used is briefly described, it should be apparent that, the accompanying drawing in describing below is only this Some embodiments of invention, for those of ordinary skill in the art, on the premise of not paying creative work, it is also possible to Other accompanying drawing is obtained according to these accompanying drawings.

The annular flange model simplification schematic diagram that Fig. 1 provides for the embodiment of the present invention；

The mechanical simplified model schematic diagram of the Flange joint that Fig. 2 provides for the embodiment of the present invention；

Four kinds of failure mode mechanical model schematic diagrams of plastic joint theory that Fig. 3 provides for the embodiment of the present invention；

The flange connection parameter schematic diagram that Fig. 4 provides for the embodiment of the present invention；

The flow process signal of the Optimization Design of the tower barrel of wind generating set flange that Fig. 5 provides for the embodiment of the present invention Figure.

Detailed description of the invention

Below in conjunction with the accompanying drawing in the embodiment of the present invention, the technical scheme in the embodiment of the present invention is carried out clear, complete Describe, it is clear that described embodiment is only a part of embodiment of the present invention rather than whole embodiments wholely.Based on Embodiment in the present invention, it is every other that those of ordinary skill in the art are obtained under not making creative work premise Embodiment, broadly falls into the scope of protection of the invention.

The embodiment of the present invention provides the Optimization Design of a kind of tower barrel of wind generating set flange, comprises in described tower Annular flange, described annular flange cross section is L-type, and described annular flange is linked in sequence by multiple single hop flanges and forms, such as Fig. 5 Shown in, described method comprises the steps:

Step 1, determines the ultimate bending moment that tower outer diameter D t, tower wall thickness s and annular flange kernel of section are subject to M, and set the diameter d of bolt.

Step 2, by distance a of annular flange inside edge to bolt axis, distance b of bolt axis to barrel center, ring Shape flange thickness t, bolt quantity n as design variable, build object function G:

$G=\mathrm{\π}\·({\mathrm{Dt}}^2-{\left(Dt-2\·a-2\·b-s\right)}^2)\·\frac{t}{4}+n\·d^2$

Wherein, object function G represents the cumulative volume of single hop flange and bolt, n ＞ 0, t ＞ 0.

Step 3, the ultimate bending moment being subject to according to described tower outer diameter D t, tower wall thickness s, annular flange kernel of section M and bolt quantity n calculates single hop flange tension.

Step 3 specifically includes:

Count according to ultimate bending moment M that described tower outer diameter D t, tower wall thickness s and annular flange kernel of section are subject to Calculation single hop flange tension Z:

$Z=\frac{4\·M}{n\·D_s}$

Wherein, n is bolt quantity, D_sFor tower barrel central diameter, D_s=Dt-s.

Step 4, sets and solves described bound for objective function, and described constraints includes: described single hop flange is subject to The pulling force arrived meets spanner spatial design rule less than the tensile bearing capacity of single hop flange, spanner bulk during assembling bolt Model, bolt hole back gauge size meets bolt hole back gauge design specification.

In step 4, single hop flange tension specifically includes less than the tensile bearing capacity of single hop flange:

(4a) under failure mode A, when L-type flange is thicker, under the effect of additional pulling force, L-type flange is sent out hardly Change shape, and high-strength bolt is by bigger pulling force, after there is bigger elongation, reaches high-strength bolt ultimate tension capacity, Final bolt abruption and L-type flange are still in elastic stage, as shown in Figure 3.The now tensile bearing capacity Z of single hop flange_A= F_{T, Rd}, F_{T, Rd}Tensile bearing capacity for single bolt:

$F_{t,Rd}=\frac{K\·A_S\·f_{ub}}{{\mathrm{\γ}}_M}$

Wherein, K is partial safety factor, A_SFor bolt stress area, γ_MFor material factor, f_ubFor bolt ultimate tensile；

Failure mode A to be met, single hop flange tension Z is necessarily less than the anti-of under failure mode A single hop flange Draw bearing capacity, owing to actual flange design can carry out rounding to the value solving the design variable that mathematical programming model obtains, for Guarantee that the design variable after rounding meets institute's Prescribed Properties, tensile bearing capacity is carried out suitable reduction, i.e. meets Z_AV-Z ＞ 0, v is reduction coefficient, v ＜ 1；

(4b) under failure mode B, the failure mode of failure mode B is that L-type flange forms plastic hinge and bolt at root Damage inactivation.This failure mode occur in the rigidity of L-type flange and high-strength bolt close time, under the effect of additional pulling force, L After the deformation of type flange and high-strength bolt tension, elongation is close.Flange and bolt almost can reach capacity bearing capacity state, Final bolt is pulled off, and flange root forms plastic hinge, as shown in Figure 3.The now tensile bearing capacity of single hop flangeWherein, bending drag M of barrel under failure mode B_{Pl, 3b}:

$M_{pl,3b}=\min \left\{\begin{array}{c}\[1-{\left(\frac{Z_B}{c\·s\·f_{ys}}\right)}^2\]\·\frac{c\·s^2\·f_{ys}}{4}\\ \[\sqrt{1-{\left(\frac{Z_B}{c\·t\·f_{yd}/\sqrt{3}}\right)}^2}\]\·\frac{c\·t^2\·f_{yd}}{4}\end{array}\right.$

Wherein,C is the approximate width of single hop flange model, f_ysAllowable for tower barrel Yield strength, f_ydYield strength allowable for annular flange；

It should be noted that M_{Pl, 3b}For the bending drag of flange or barrel, take the two smaller value.Owing to flange thickness is general More than wall thickness, simplification herein processes and takes barrel bending drag.

Failure mode B to be met, single hop flange tension Z is necessarily less than the anti-of under failure mode B single hop flange Draw bearing capacity, i.e. meet Z_BV-Z ＞ 0, v are reduction coefficient, v ＜ 1；

(4c) under failure mode D, surrender at the root of L-type flange and bolt position.When the bolt rigidity connected is more than L During the rigidity of type flange or tower barrel, the deformation of L-type flange is more than high-strength bolt elongation, and flange periphery forms thick stick earlier Stick force, during destruction, the position of plastic hinge and distribution are as shown in Figure 3.The now tensile bearing capacity of single hop flangeWherein, the addition bend drag that at bolt hole, single hop flanges bend drag and bolt bias produce M′_{Pl, 2}:

${M^{\′}}_{pl,2}=\frac{c^{\′}\·t^2\·f_{yd}}{4}+\frac{F_{t,Rd}}{2}\·\frac{d_S+d_B}{4}$

Bending drag M of barrel under failure mode D_{Pl, 3d}:

$M_{pl,3d}=\min \left\{\begin{array}{c}\[1-{\left(\frac{Z_D}{c\·s\·f_{ys}}\right)}^2\]\·\frac{c\·s^2\·f_{ys}}{4}\\ \[\sqrt{1-{\left(\frac{Z_D}{c\·t\·f_{yd}/\sqrt{3}}\right)}^2}\]\·\frac{c\·t^2\·f_{yd}}{4}\end{array}\right.$

C '=c-d_B

b_D=b

Wherein, c ' is the approximate width of the single hop flange model after reduction at bolt hole, d_BFor diameter of bolt hole, d_SFor pad Circle external diameter, b_DDistance for bolt axis to barrel plastic hinge；

Failure mode D to be met, single hop flange tension Z is necessarily less than the anti-of under failure mode D single hop flange Draw bearing capacity, i.e. meet Z_DV-Z ＞ 0, v are reduction coefficient, v ＜ 1；

(4d) under failure mode E, failure mode E is root and the surrender of packing ring root position of L-type flange.When connect When packing ring rigidity is more than the rigidity of L-type flange or tower barrel, the deformation of L-type flange is more than high-strength bolt elongation, flange Edge forms lever force earlier, and during destruction, the position of plastic hinge and distribution are as shown in Figure 3.The now tensile bearing capacity of single hop flangeWherein, bending drag M of barrel under failure mode E_{Pl, 3e}:

$M_{pl,3e}=\min \left\{\begin{array}{c}\[1-{\left(\frac{Z_E}{c\·s\·f_{ys}}\right)}^2\]\·\frac{c\·s^2\·f_{ys}}{4}\\ \[\sqrt{1-{\left(\frac{Z_E}{c\·t\·f_{yd}/\sqrt{3}}\right)}^2}\]\·\frac{c\·t^2\·f_{yd}}{4}\end{array}\right.$

$b_E=b-\frac{d_S+d_B}{4}$

$M_{pl,2}=\frac{c\·t^2\·f_{yd}}{4}$

M_{Pl, 2}For single hop flanges bend drag, b_EDistance for gasket width center to plastic hinge；

Failure mode E to be met, single hop flange tension Z is necessarily less than the anti-of under failure mode E single hop flange Draw bearing capacity, i.e. meet Z_EV-Z ＞ 0, v are reduction coefficient, v ＜ 1.

In step 4, spanner bulk during assembling bolt meets spanner spatial design specification, particularly as follows:

Obtain according to the design specification that JB/ZQ 4005-2006 specifies: minimum between tower single hop flange bolt Circumferential distance A2 and minimum spacing E1 of bolt distance barrel, thus obtain following constraints；

(Dt-2·b-s)·π/n≥0

b-s/2-E1≥0

Wherein, Dt represents tower external diameter, and s represents tower wall thickness, and b represents the bolt axis distance to barrel center, n Representing bolt quantity, E1 represents the minimum spacing of bolt distance barrel.

In step 4, bolt hole back gauge size meets bolt hole back gauge design specification, particularly as follows:

According to the regulation of EN 1993-1-8, bolt hole center to structure edge distance more than or equal to the 1.2 of bolt aperture Times, thus obtain following constraints:

a-1.2·d_B≥0

Wherein, a represents the annular flange inside edge distance to bolt axis, d_BRepresent the diameter of bolt hole.

Step 5, according to described object function and constraints, sets up mathematical programming model, solves described Mathematical Planning Model, obtains the one group design variable minimum so that described object function, and single hop flange corresponding to this group design variable and The cumulative volume of bolt.

In step 5, according to described object function and constraints, set up mathematical programming model as follows:

Object function:

Constraints: Z_iV-Z ＞ 0 (i=A, B, D, E)

(Dt-2·b-s)·π/n≥0

b-s/2-E1≥0

a-1.2·d_B≥0

N ＞ 0

T ＞ 0

Wherein, Dt represents tower external diameter, and s represents tower wall thickness, and M represents the limit that annular flange kernel of section is subject to Moment of flexure, d represents the diameter of bolt, and a represents the annular flange inside edge distance to bolt axis, and b represents that bolt axis is to barrel The distance at center, t represents annular flange thickness, and n represents bolt quantity, Z_i(i=A, B, C, D) represents at failure mode A, B, C Or the tensile bearing capacity of single hop flange under D, Z represents single hop flange tension, and v is reduction coefficient, and E1 represents bolt distance The minimum spacing of barrel, d_BRepresent diameter of bolt hole.

Mathematical programming model derived above is a nonlinear mathematics programming model, solves it, is designed Variable (exemplary, can be L-type flange arrangement parameter a, b, n, numerical value t), and corresponding single hop flange and bolt Cumulative volume.

Further, use Direct search algorithm (Direct search algorithms) to nonlinear mathematics programming mould Type solves.

Step 6, resets the diameter d of bolt, and is repeated in step 2 to step 5, until obtaining organizing design change more Amount, and organize single hop flange corresponding to design variable and the cumulative volume of bolt more.

Step 7, the one group of design choosing the cumulative volume so that single hop flange and bolt in many group design variables minimum becomes Measure the structural parameters as single hop Flange joint.

According to existing example and experience, after the diameter that bolt is varied multiple times and relevant parameter, several groups of L-types can be obtained Flange arrangement parameter value, and flange and the cumulative volume of bolt accordingly.Through contrast, one group of numerical value of volume minimum is Excellent solution.

Solve the design variable value that mathematical programming model obtains and be generally floating number, have certain decimal digits, for bolt It is integer that the such parameter of quantity n has clearly a need for rounding, and remaining flange parameter is typically also required to rounding in actual design and rounds Number or priority number.Design variable after rounding is designed checking for four failure modes, if by, obtain optimal solution, If not passing through, revising reduction coefficient v, redesigning.

The method for designing that the present invention describes is applicable to the flange that cross section is L-type, and this method is equally applicable after modifying It is T-shaped flange in design cross section.

Exemplary, Practical Project realizes can refer to procedure below:

1. draft known conditions

According to the existing parameter of certain blower fan tower barrel, proposing meter flange position tower outer diameter D t is 3940mm, and tower barrel is thick Degree s is 22mm, and flange and barrel material are Q345, follows the example of blue yield strength f allowable_ydFor 304.5MPa, take barrel allowable in the wrong Take intensity f_ysFor 313.6MPa, ultimate bending moment M at flange kernel of section is 53000kNm.Four kinds of bolts are selected (to be not limited to this Four kinds) nominal diameter be designed respectively.Bolt parameter is as follows:

Set up and solve the mathematical programming model of flange structural parameters:

Parameter and the flange known conditions of four kinds of bolts are brought into following equation and set up nonlinear mathematics programming model.Take v It is 0.99.

Minimize G (a, b, n, t)

$G=\mathrm{\π}\·({\mathrm{Dt}}^2-{\left(Dt-2\·a-2\·b-s\right)}^2)\·\frac{t}{4}+n\·d^2\·t$

Constraints: Z_iV-Z (i=A, B, D, E)

(Dt-2·b-s)·π/n≥0

b-s/2-E1≥0

a-1.2·db≥0

N ＞ 0

T ＞ 0

Solving method mathematical programming model, and find out optimal case:

Direct search algorithm (Direct search algorithms) is used to solve above-mentioned nonlinear mathematics programming model, Obtain four groups of flange parameters and gross weight be as follows:

As can be seen from the above table, the scheme that volume is minimum is the one group of data using M42 bolt.

The flange parameter of optimal case is carried out rounding and verifies

According to actual design needs, optimization design scheme being carried out rounding, the flange parameter after rounding is:

The calculating of the tensile bearing capacity that the parameter after rounding is brought into four kinds of failure modes of the L-type flange theory of plasticity is public Formula, can obtain:

$Z_A=\frac{K\·A_S\·f_{ub}}{{\mathrm{\γ}}_M}=807068.7N$

$Z_B=\frac{F_{t,Rd}\·a+M_{pl,3}}{a+b}=443497.4N$

$Z_D=\frac{{M^{\′}}_{pl,2}+M_{pl,3}}{b_D}=443895.9N$

$Z_E=\frac{M_{pl,2}+M_{pl,3}}{b_E}=762180.5N$

Now the ultimate tension at flange barrel is:

$Z=\frac{4\·M}{n\·d_s}=436364.8N$

Ultimate tension is less than all tensile bearing capacity, and check is passed through.

Present invention basic theories based on Mathematical Planning, is reduced to single hop flange even by the mechanical model that annular flange connects Connect, with the structural parameters of tower drum flange as design variable, the failure mode of four kinds of theories of plasticity, the spanner space of bolt and bolt Hole back gauge a size of about restraints condition, sets up the mathematical programming model using the cumulative volume of flange and bolt as object function, finally Optimized algorithm is used to solve the flange connection that the cumulative volume obtaining making flange and bolt is minimum.Application the method obtains quality The lightest and meet the optimized flange connection of four kinds of failure modes of flange Plastic Design.This method is easily programmed realization, The amount of calculation of designer can be reduced, improve rapidity and the accuracy of design.

The above, the only detailed description of the invention of the present invention, but protection scope of the present invention is not limited thereto, and any Those familiar with the art, in the technical scope that the invention discloses, can readily occur in change or replace, should contain Cover within protection scope of the present invention.Therefore, protection scope of the present invention should be as the criterion with described scope of the claims.

Claims (6)

1. an Optimization Design for tower barrel of wind generating set flange, comprises annular flange, described annular in described tower Flange cross section is L-type, and described annular flange is linked in sequence by multiple single hop flanges and forms, it is characterised in that described method bag Include following steps:

Step 1, determines ultimate bending moment M that tower outer diameter D t, tower wall thickness s and annular flange kernel of section are subject to, and Set the diameter d of bolt；

Step 2, by distance a of annular flange inside edge to bolt axis, distance b of bolt axis to barrel center, loop method Blue thickness t, bolt quantity n, as design variable, build object function G:

$G=\mathrm{\π}\·({\mathrm{Dt}}^2-{\left(Dt-2\·a-2\·b-s\right)}^2)\·\frac{t}{4}+n\·d^2$

Wherein, object function G represents the cumulative volume of single hop flange and bolt, n ＞ 0, t ＞ 0；

Step 3, ultimate bending moment M being subject to according to described tower outer diameter D t, tower wall thickness s, annular flange kernel of section with And bolt quantity n calculates single hop flange tension；

Step 4, sets and solves described bound for objective function, and described constraints includes: described single hop flange is subject to Pulling force meets spanner spatial design specification, spiral shell less than the tensile bearing capacity of single hop flange, spanner bulk during assembling bolt Keyhole back gauge size meets bolt hole back gauge design specification；

Step 5, according to described object function and constraints, sets up mathematical programming model, solves described mathematical programming model, Obtain the one group design variable minimum so that described object function, and single hop flange corresponding to this group design variable and bolt Cumulative volume；

Step 6, resets the diameter d of bolt, and is repeated in step 2 to step 5, until obtaining organizing design variable more, with And organize single hop flange corresponding to design variable and the cumulative volume of bolt more；

Step 7, the one group of design variable choosing the cumulative volume so that single hop flange and bolt minimum in many group design variables is made Structural parameters for single hop Flange joint.

The Optimization Design of a kind of tower barrel of wind generating set flange the most according to claim 1, it is characterised in that step Rapid 3 specifically include:

Ultimate bending moment M being subject to according to described tower outer diameter D t, tower wall thickness s and annular flange kernel of section calculates single Duan Falan tension Z:

$Z=\frac{4\·M}{n\·D_s}$

Wherein, n is bolt quantity, D_sFor tower barrel central diameter, D_s=Dt-s.

The Optimization Design of a kind of tower barrel of wind generating set flange the most according to claim 1, it is characterised in that step In rapid 4, single hop flange tension specifically includes less than the tensile bearing capacity of single hop flange:

(4a) under failure mode A, the tensile bearing capacity Z of single hop flange_A=F_{T, Rd}, F_{T, Rd}Tensile bearing capacity for single bolt:

$F_{t,Rd}=\frac{K\·A_S\·f_{ub}}{{\mathrm{\γ}}_M}$

Wherein, K is partial safety factor, A_SFor bolt stress area, γ_MFor material factor, f_ubFor bolt ultimate tensile；

Failure mode A to be met, single hop flange tension Z is necessarily less than the tension of single hop flange under failure mode A and holds Load power, i.e. meets Z_AV-Z ＞ 0, v are reduction coefficient, v ＜ 1；

(4b) under failure mode B, the tensile bearing capacity of single hop flangeWherein, in failure mode Bending drag M of barrel under B_P1,3b:

$M_{pl,3b}=\min \left\{\begin{array}{c}\[1-{\left(\frac{Z_B}{c\·s\·f_{ys}}\right)}^2\]\·\frac{c\·s^2\·f_{ys}}{4}\\ \[\sqrt{1-{\left(\frac{Z_B}{c\·t\·f_{yd}/\sqrt{3}}\right)}^2}\]\·\frac{c\·t^2\·f_{yd}}{4}\end{array}\right.$

Wherein,C is the approximate width of single hop flange model, f_ysSurrender allowable for tower barrel is strong Degree, f_ydYield strength allowable for annular flange；

Failure mode B to be met, single hop flange tension Z is necessarily less than the tension of single hop flange under failure mode B and holds Load power, i.e. meets Z_BV-Z ＞ 0, v are reduction coefficient, v ＜ 1；

(4c) under failure mode D, the tensile bearing capacity of single hop flangeWherein, single hop at bolt hole The addition bend drag M ' that flanges bend drag and bolt bias produce_P1,2:

${M^{\′}}_{pl,2}=\frac{c^{\′}\·t^2\·f_{yd}}{4}+\frac{F_{t,Rd}}{2}\·\frac{d_S+d_B}{4}$

Bending drag M of barrel under failure mode D_P1,3d:

$M_{pl,3d}=\min \left\{\begin{array}{c}\[1-{\left(\frac{Z_D}{c\·s\·f_{ys}}\right)}^2\]\·\frac{c\·s^2\·f_{ys}}{4}\\ \[\sqrt{1-{\left(\frac{Z_D}{c\·t\·f_{yd}/\sqrt{3}}\right)}^2}\]\·\frac{c\·t^2\·f_{yd}}{4}\end{array}\right.$

C '=c-d_B

b_D=b

Wherein, c ' is the approximate width of the single hop flange model after reduction at bolt hole, d_BFor the diameter of bolt hole, d_SFor packing ring External diameter, b_DDistance for bolt axis to barrel plastic hinge；

Failure mode D to be met, single hop flange tension Z is necessarily less than the tension of single hop flange under failure mode D and holds Load power, i.e. meets Z_DV-Z ＞ 0, v are reduction coefficient, v ＜ 1；

(4d) under failure mode E, the tensile bearing capacity of single hop flangeWherein, under failure mode E Bending drag M of barrel_P1,3e:

$M_{pl,3e}=\min \left\{\begin{array}{c}\[1-{\left(\frac{Z_E}{c\·s\·f_{ys}}\right)}^2\]\·\frac{c\·s^2\·f_{ys}}{4}\\ \[\sqrt{1-{\left(\frac{Z_E}{c\·t\·f_{yd}/\sqrt{3}}\right)}^2}\]\·\frac{c\·t^2\·f_{yd}}{4}\end{array}\right.$

$b_E=b-\frac{d_S+d_B}{4}$

$M_{pl,2}=\frac{c\·t^2\·f_{yd}}{4}$

M_P1,2For single hop flanges bend drag, b_EDistance for gasket width center to plastic hinge；

Failure mode E to be met, single hop flange tension Z is necessarily less than the tension of single hop flange under failure mode E and holds Load power, i.e. meets Z_EV-Z ＞ 0, v are reduction coefficient, v ＜ 1.

The Optimization Design of a kind of tower barrel of wind generating set flange the most according to claim 1, it is characterised in that step In rapid 4, spanner bulk during assembling bolt meets spanner spatial design specification, particularly as follows:

Obtain according to the design specification that JB/ZQ 4005-2006 specifies: circumference minimum between tower annular flange connecting bolt Distance A2 and minimum spacing E1 of bolt distance barrel, thus obtain following constraints:

(Dt-2·b-s)·π/n≥0

b-s/2-E1≥0

Wherein, Dt represents tower external diameter, and s represents tower wall thickness, and b represents the bolt axis distance to barrel center, and n represents Bolt quantity, E1 represents the minimum spacing of bolt distance barrel.

The Optimization Design of a kind of tower barrel of wind generating set flange the most according to claim 1, it is characterised in that step In rapid 4, bolt hole back gauge size meets bolt hole back gauge design specification, particularly as follows:

According to the regulation of EN 1993-1-8, bolt hole center to structure edge distance more than or equal to 1.2 times of bolt aperture, from And obtain following constraints:

a-1.2·d_B≥0

Wherein, a represents the annular flange inside edge distance to bolt axis, d_BRepresent the diameter of bolt hole.

The Optimization Design of a kind of tower barrel of wind generating set flange the most according to claim 1, it is characterised in that step In rapid 5, according to described object function and constraints, set up mathematical programming model as follows:

Object function:

Constraints: Z_iV-Z ＞ 0 (i=A, B, D, E)

(Dt-2·b-s)·π/n≥0

b-s/2-E1≥0

a-1.2·d_B≥0

N ＞ 0

T ＞ 0

Wherein, Dt represents tower external diameter, and s represents tower wall thickness, and M represents that the limit that annular flange kernel of section is subject to is curved Square, d represents the diameter of bolt, and a represents the annular flange inside edge distance to bolt axis, and b represents that bolt axis is in barrel The distance of the heart, t represents annular flange thickness, and n represents bolt quantity, Z_i(i=A, B, C, D) represents at failure mode A, B, C or D The tensile bearing capacity of lower single hop flange, Z represents single hop flange tension, and v is reduction coefficient, and E1 represents bolt distance barrel Minimum spacing, d_BRepresent diameter of bolt hole.