Abaqus中接触分析（隐式求解 Standard）

目录

  1. 引言
  2. 通用接触（general contact）
  3. 接触对（contact pair）

引言

  Abaqus中对于接触这类分析时，通常涉及到非线性求解的问题，特别是针对隐式求解（standard ），求解的过程中往往会出现难以收敛的问题；这时需要设置针对接触求解的参数，以加快求解的收敛速度。

  在Abaqus中常用的接触算法分为两种：

  • 通用接触（general contact）
  • 接触对（contact pair）

通用接触（general contact）

  定义通用接触的关键字如下，*CONTACT表示设置接触，*CONTACT INCLUSIONS表示设置需要接触的区域，而ALL EXTERIOR参数表示设置整个模型为接触区域。

*CONTACT
**定义整个模型为自接触
*CONTACT INCLUSIONS, ALL EXTERIOR

  通常在设置接触时，不会设置整个模型为接触区域，可使用关键字*CONTACT EXCLUSIONS排除该区域，关键字信息如下：

*CONTACT
*CONTACT INCLUSIONS, ALL EXTERIOR
*CONTACT EXCLUSIONS
surface_1,

  当涉及不需要设置的接触区域过多时，可直接定义目标区域的接触；在设置目标区域的接触前，需要通过*SURFACE,  TYPE = ELEMENT，NAME = Contact_Surface_Name，关键字信息如下：

**定义接触面
*Surface, NAME = Contact_Surface_Name01, TYPE = ELEMENT
...
*Surface, NAME = Contact_Surface_Name02, TYPE = ELEMENT
...
*CONTACT
*CONTACT INCLUSIONS
Contact_Surface_Name01, Contact_Surface_Name02

通用接触的属性定义

  通用接触的属性定义的关键字如下，*CONTACT PROPERTY ASSIGNMENT关键字设置接触的属性，定义摩擦属性的关键字为*SURFACE INTERACTION和*FRICTION。

*SURFACE INTERACTION, NAME=contProp1
*FRICTION
0.1
*SURFACE INTERACTION, NAME=contProp2
*FRICTION
0.15
*SURFACE INTERACTION, NAME=contProp3
*FRICTION
0.20
*CONTACT
*CONTACT INCLUSIONS, ALL EXTERIOR
**定义整个模型的接触属性
*CONTACT PROPERTY ASSIGNMENT
 , , contProp1 
 **定义目标接触区的属性
surf1, surf1, contProp2 
**定义目标接触区无属性
surf2, surf3,
 , surf4, contProp3

通用接触中问题分析

  在定义上面的接触关键字后，如果FEA模型设置正确，可直接提交计算，获取结果；但是通常模型因为各种原导致求解过程中难以收敛，报错信息如下，FEA模型在接触过程中出现了节点穿透的问题，导致求解不能收敛。

  STA文件中信息，求解未收敛。

Sta file 
  SUMMARY OF JOB INFORMATION:
 STEP  INC ATT SEVERE EQUIL TOTAL  TOTAL      STEP       INC OF       DOF    IF
               DISCON ITERS ITERS  TIME/    TIME/LPF    TIME/LPF    MONITOR RIKS
               ITERS               FREQ
   1     1   1     1     0     1  0.00100    0.00100    0.001000  
   1     2   1     1     0     1  0.00200    0.00200    0.001000  
   1     3   1     4     1     5  0.00350    0.00350    0.001500  
   1     4   1     2     3     5  0.00575    0.00575    0.002250  
   1     5   1U    9     2    11  0.00575    0.00575    0.003375  
   1     5   2     1     4     5  0.00659    0.00659    0.0008438 
   1     6   1     1     4     5  0.00786    0.00786    0.001266  
   1     7   1    16     3    19  0.00976    0.00976    0.001898  
   1     8   1U    5     0     5  0.00976    0.00976    0.001424  
   1     8   2     8     2    10  0.0101     0.0101     0.0003560 
   1     9   1     2     2     4  0.0105     0.0105     0.0003560 
   1    10   1     4     2     6  0.0110     0.0110     0.0005339 
   1    11   1     4     2     6  0.0118     0.0118     0.0008009 
   1    12   1     4     2     6  0.0130     0.0130     0.001201  
   1    13   1     5     1     6  0.0148     0.0148     0.001802  
   1    14   1    16     2    18  0.0175     0.0175     0.002703  
   1    15   1     2     2     4  0.0195     0.0195     0.002027  
   1    16   1     2     2     4  0.0216     0.0216     0.002027  
   1    17   1     1     3     4  0.0246     0.0246     0.003041  
   1    18   1     3     2     5  0.0292     0.0292     0.004561  
   1    19   1    20     2    22  0.0360     0.0360     0.006842  
   1    20   1     4     2     6  0.0411     0.0411     0.005132  
   1    21   1     3     3     6  0.0463     0.0463     0.005132  
   1    22   1     1     2     3  0.0540     0.0540     0.007697  
   1    23   1     1     2     3  0.0655     0.0655     0.01155   
   1    24   1     1     3     4  0.0828     0.0828     0.01732   
   1    25   1     1     3     4  0.109      0.109      0.02598   
   1    26   1U    4     0     4  0.109      0.109      0.03897   
   1    26   2U    5     0     5  0.109      0.109      0.009742  
   1    26   3U    6     0     6  0.109      0.109      0.002435  
   1    26   4U    6     0     6  0.109      0.109      0.0006089 
   1    26   5U    6     0     6  0.109      0.109      0.0001522 
                          
 THE ANALYSIS HAS NOT BEEN COMPLETED

  MSG文件中接触穿透导致求解收敛问题。

   MAX. PENETRATION ERROR 15.1633E-24  AT NODE 10024 OF CONTACT PAIR 
   (GENERAL_CONTACT_FACES_3,GENERAL_CONTACT_FACES_1)
   MAX. CONTACT FORCE ERROR -35.6223E-15  AT NODE 9957 OF CONTACT PAIR 
   (GENERAL_CONTACT_FACES_3,GENERAL_CONTACT_FACES_1)
          THE CONTACT CONSTRAINT ERRORS ARE WITHIN THE TOLERANCES.

  针对模型之间出现的间隙（GAP）和穿透（OVERCLOSURE）问题，可通过设置关键字（INP文件中修改）在初始接触状态消除这些情况，*CONTACT INITIALIZATION DATA关键字设置处理初始接触的算法，*CONTACT INITIALIZATION ASSIGNMENT关键字指定目前接触区域使用的算法，关键字信息如下：

**处理基本间隙和穿透的接触状态
**CONTACT INITIALIZATION DATA, INITIAL CLEARANCE=0.1,NAME=clearance_name
**处理过穿透的接触状态 	
**CONTACT INITIALIZATION DATA, INTERFERENCE FIT=h, SEARCH ABOVE=a, SEARCH BELOW=b
*CONTACT INITIALIZATION DATA, NAME=shrink_fit, INTERFERENCE FIT
*CONTACT INITIALIZATION DATA, NAME=shrink_fit_local,
   INTERFERENCE FIT, SEARCH BELOW = 15.0
*CONTACT INITIALIZATION DATA, NAME=sfa_pickside, 
   SEARCH BELOW = 10.0
…
*CONTACT
*CONTACT INCLUSIONS, ALL EXTERIOR
**设置初始状态处理的接触方法
*CONTACT INITIALIZATION ASSIGNMENT
**整个模型都应用该方法
 , , shrink_fit 
 **目标接触区域的处理方法
surface_A, surface_B, shrink_fit_local
surface_C, surface_D, 
surface_1_TOP, surface_2_BOTTOM, sfa_pickside

  *CONTACT INITIALIZATION DATA, INITIAL CLEARANCE=h（h设置搜索范围）

  CLEAERANCE方法可无应变的消除初始的间隙和穿透状态，即通过算法层面消除，将节点拉回到无穿透和间隙的情况。需要注意该方法，可能会导致网格过度畸变问题。

image

  无应变的初始节点状态适应调整

  *CONTACT INITIALIZATION DATA, NAME=shrink_fit, INTERFERENCE FIT=h（h设置搜索范围）

  INTERFERENCE FIT方法为求解过程中逐步消除干涉问题，但是产生一定额外的应力和应变。

image

逐步消除干涉过程

FEA模型

  如下图的FEA模型，对该模型施加位移预紧力，具体模型信息可参考（Abaqus螺栓施加预紧力 ），该模型中接触的使用了Tie和通用接触（general contact）。

 image image

FEA模型和接触区域信息

INP文件（通用接触）

关键字设置信息（*CONTACT INITIALIZATION DATA, INTERFERENCE FIT=0.1,NAME=clearance_M  ）

strain-free adjustment（INITIAL CLEARANCE） 
 *INCLUDE, INPUT=TestContact01_2_fit.inp
*Surface, NAME = Shell_M, TYPE = ELEMENT
_Shell_M_S1,S1
_Shell_M_S2,S2
_Shell_M_S3,S3
_Shell_M_S4,S4
*ELSET, ELSET = _pre_surface_S1, GENERATE
121695,136759,56
*Surface, NAME = pre_surface, TYPE = ELEMENT
_pre_surface_S1,S1
**HMNAME MATS          1 Steel     3
*MATERIAL, NAME=Steel
*DENSITY
7.8900E-09,0.0       
*ELASTIC, TYPE = ISOTROPIC
200000.0  ,0.3       ,0.0       
**HMNAME PROPERTY          2 fri
*SURFACE INTERACTION, NAME = fri
*FRICTION
0.1       , 0.0       ,0.0       ,0.0       
**HMNAME GROUPS          1 pre_surface
*PRE-TENSION SECTION, NODE=20345, SURFACE=pre_surface
*TIE, NAME = Tie01
Bolt_S01,Bolt_M
**无应变初始调整
*CONTACT INITIALIZATION DATA, INITIAL CLEARANCE=0.1,NAME=clearance_M
*CONTACT
*CONTACT INCLUSIONS
Bolt_M, Bolt_S02
Shell_M, Shell_S
*CONTACT INITIALIZATION ASSIGNMENT
 , , clearance_M 
*CONTACT PROPERTY ASSIGNMENT
Bolt_M, Bolt_S02, fri
Shell_M, Shell_S, fri
*CONTACT FORMULATION,TYPE=EDGE TO EDGE,FORMULATION=BOTH
**HMNAME LOADSTEP          1 pre-step
*STEP, INC =          100
*STATIC
1.0000E-03,1.0       ,1.0000E-05,0.2       
**HWNAME LOADCOL          1 Pre_Force
**HWCOLOR LOADCOL          1     4
*BOUNDARY
20345,1, ,1.0            
**HWNAME LOADCOL          2 BC
**HWCOLOR LOADCOL          2    21
*BOUNDARY
20344,1,6,0.0
*OUTPUT, FIELD, FREQUENCY = 1
*NODE OUTPUT
U
*ELEMENT OUTPUT
S
*END STEP
*****

关键字设置信息（*CONTACT INITIALIZATION DATA, INTERFERENCE FIT=0.1,NAME=clearance_M  ）

Interference fit(INTERFERENCE FIT) 
 **TestContact.inp文件为模型的网格信息
*INCLUDE, INPUT=TestContact.inp
*Surface, NAME = Shell_M, TYPE = ELEMENT
_Shell_M_S1,S1
_Shell_M_S2,S2
_Shell_M_S3,S3
_Shell_M_S4,S4
*ELSET, ELSET = _pre_surface_S1, GENERATE
121695,136759,56
*Surface, NAME = pre_surface, TYPE = ELEMENT
_pre_surface_S1,S1
**HMNAME MATS          1 Steel     3
*MATERIAL, NAME=Steel
*DENSITY
7.8900E-09,0.0       
*ELASTIC, TYPE = ISOTROPIC
200000.0  ,0.3       ,0.0       
**HMNAME PROPERTY          2 fri
*SURFACE INTERACTION, NAME = fri
*FRICTION
0.1       , 0.0       ,0.0       ,0.0       
**HMNAME GROUPS          1 pre_surface
*PRE-TENSION SECTION, NODE=20345, SURFACE=pre_surface
*TIE, NAME = Tie01
Bolt_S01,Bolt_M
**求解过程中逐渐调整
*CONTACT INITIALIZATION DATA, INTERFERENCE FIT=0.1,NAME=clearance_M 	
*CONTACT
*CONTACT INCLUSIONS
Bolt_M, Bolt_S02
Shell_M, Shell_S
*CONTACT INITIALIZATION ASSIGNMENT
 , , clearance_M 
*CONTACT PROPERTY ASSIGNMENT
Bolt_M, Bolt_S02, fri
Shell_M, Shell_S, fri
*CONTACT FORMULATION,TYPE=EDGE TO EDGE,FORMULATION=BOTH
**HMNAME LOADSTEP          1 pre-step
*STEP, INC =          100
*STATIC
1.0000E-03,1.0       ,1.0000E-05,0.2       
**HWNAME LOADCOL          1 Pre_Force
**HWCOLOR LOADCOL          1     4
*BOUNDARY
20345,1, ,1.0            
**HWNAME LOADCOL          2 BC
**HWCOLOR LOADCOL          2    21
*BOUNDARY
20344,1,6,0.0
*OUTPUT, FIELD, FREQUENCY = 1
*NODE OUTPUT
U
*ELEMENT OUTPUT
S
*END STEP
*****

FEA结果（通用接触）

  根据下图FEA结果可知，相比于Interference fit方法，Strain-free adjustment方法不会产生额外的应力。

image

左（Strain-free adjustment）右（Interference fit ）

接触对（contact pair）

 

 

INP文件

FEA的网格信息

参考

Defining general contact interactions for implicit method

 

posted @ 2026-02-01 20:28  SwingGodLin  阅读(2)  评论(0)    收藏  举报