例17 铝板焊接温度场分析实例—多层多道焊

例17 铝板焊接温度场分析实例—多层多道焊17.1 问题描述
模拟一块铝合金板材多层多道焊接过程。

17.2 建立有限元模型
MAIN
MESH GENERA TION
NODES:ADD (创建4个节点)
00 0
0.050 0
0.050.05 0
00.05 0
ELEMENTS:ADD (用上述4个节点创建单元)
1 2 3 4
END LIST#
SUBDIVIDE (进行网格划分，采用疏密网格过渡)
DIVISIONS
2020 1
BIAS FACTORS
0.350 0
ELEMENTS
ALL:EXISTING
RETURN
EXPAND
TRANSLATIONS
00 -0.001
RPETITIONS 10
ELEMENTS
ALL:EXISTING
RETURN （创建的网格模型如下图）
SWEEP
ALL
RENUMBER
ALL
SELECT
ELEMENTS:STORE
filler
OK
(选中图中所示的
绿色区域)
ALL:SELECT
SELECT SET: filler
MAKE INVISIBLE
ELEMENTS:STORE
solid
OK
ALL:VISIBLE
17.3 施加材料性能
MATERIAL PROPERTIES
NEW (定义母材和填充材料的材料性质) ISOTROPIC
YOUNG’S MODULOUS 69e9
POSISON’S RA TIO 0.33
MASS DENSITY 2700
PLASTICITY
ELASTIC-PLASTIC
INITIAL YIELD STRESS 8e8
THERMAL.EXP
COEFFICIENT 23.1e-6
OK
HEAT TRANSFER
CONDUCTIVITY 240
SPECIFIC HEA T 880
MASS DENSITY 2700
OK
ELEMENTS:ADD
ALL:EXISTING
RETURN
17.4 建立焊接路径和焊道
MODELING TOOLS
WEID FILLER (选定填充材料)
NEW
NAME:weldfiller1 (定义填充材料1，为恒温热源)
PARAMETERS:
MELT POINT TEMP: 660
ELEMENTS:ADD (选定图中所示的粉色单元)
END LIST#
NEW （定义填充材料2，为恒温热源）
NAME:weldfiller2
PARAMETERS:
MELT POINT TEMP: 660
ELEMENTS:ADD (选定图中所示的橙色单元)
END LIST#
NEW （定义填充材料3，为恒热流密度源）
NAME:weldfiller3
ELEMENTS:ADD (选定图中所示的黄色单元)
END LIST#
RETURN
WELD PATHS （创建焊接路径）
NEW （定义焊接路径1）
SELECT SET: weldfiller1
MAKE INVISIBLE
PA TH INPUT:NODES
NODES:ADD
选中图示中最上面的2个节点
END LIST#
ORIENTATION INPUT METHOD
NODES: ADD
选中图示中的最下面的那个点
END LIST#
同样的方法定义焊接路径2，3
RETURN
17.5 设置焊道和母材的接触关系CONTACT
CONTACT BODIES
NEW
NAME:filler1
DEFORMABLE
OK
ELEMENTS:ADD
SET filler1
OK
ALL:SELECT
NEW
NAME:filler2
DEFORMABLE
OK
ELEMENTS:ADD
SET filler2
OK
ALL:SELECT
END LIST#
NEW
NAME:filler3
DEFORMABLE
OK
ELEMENTS:ADD
SET filler3
OK
ALL:SELECT
END LIST#
NEW
NAME:solid
DEFORMABLE
OK
ELEMENTS:ADD
SET solid
OK
ALL:SELECT
END LIST# (接触体如图所示)
CONTACT TABLES
NEW
PROPERTIES
FIRST 1:2
CONTACT TYPE:GLUE
THERMAL PROPERTIES:
CONTACT HEAT TRANSFER COEFFICIENT: 1e6
OK
RETURN
RETUEN
同样的操作定于接触体1与3，1与4，2与3，3与4之间的接触关系
17.6 设置边界条件
BOUNDARY CONDITIONS
NEW
NAME:flux1 (指定焊接热源为体热源)
BOUNDARY CONDITIONS TYPE
THERMAL:MORE
VOLUME WELD FLUX
FLUX (on)
DIMENSIONS: (定义焊缝的尺寸)
WIDTH:0.006
DEPTH:0.006
FORW ARD LENGTH:0.004
REAR LENGTH:0.01
MOTION PARAMETER: （指定热源的运动参数）
VELOCITY:0.0025
WELD PATH:weldpath1
WELD FILLER:weldfiller1
OK
ELEMENTS:ADD
ALL:EXISTING
END LIST#
RETURN
同样的条件定义焊接热源2
NEW
NAME:flux3 (指定焊接热源为体热源)
VOLUME WELD FLUX
FLUX(on)
MAGNITUDE
POWER 3000
EFFICIENCY 0.7
DIMENSIONS: (定义焊缝的尺寸)
WIDTH:0.008
DEPTH:0.008
FORW ARD LENGTH:0.005
REAR LENGTH:0.012
MOTION PARAMETER: （指定热源的运动参数）
VELOCITY:0.0025
WELD PATH:weldpath3
WELD FILLER:weldfiller3
OK
ELEMENTS:ADD
ALL:EXISTING
END LIST#
RETURN
NEW
NAME:film (指定与外界的对流交换)
BOUNDARY CONDITIONS TYPE
THERMAL:FACE FILM
FILM
COEFFICIENT:20
SINK TEMPERATYRE:60
OK
FACES:ADD
选定除填充材料以外的表面
END LIST#
RETURN （与外界热交换的边界条件如下图）
NEW
NAME:fix_xy
MACHANICAL
FIXED DISPLACEMENT
ON X DISPLACEMENT
ON Y DISPLACEMENT
OK
NODES:ADD (选择左端的所有节点)
END LIST(#)
NEW
NAME:fix_z
MACHANICAL
FIXED DISPLACEMENT
ON Z DISPLACEMENT
OK
NODES:ADD (选择底边上的所有端点)
END LIST(#)
17.7 定义工况
LOADCASES
NEW
COUPLED
QUASI-STATIC (定义载荷工况1,焊接过程)
LOADS:flux1(on)
film(on)
fix_xy(on)
fix_z(on)
OK
CONTACT
CONTACT TABLE:ctable1
OK
CONVERGENCE TESTING
MAX ERROR IN TEMPERATURE ESTIMATE:50
OK
TOTAL LOADCASES TIME: 20
FIXED:CONSTANT TIME STEP:
PARAMETER:
#STEP: 50
OK
OK
同样的方法定义载荷工况2，3
NEW
COUPLED
QUASI-STATIC (定义载荷工况4，焊后的冷却过程) LOADS:film(on)
fix_xy(on)
fix_z(on)
OK
CONTACT
CONTACT TABLE:ctable1
OK
CONVERGENCE TESTING
MAX ERROR IN TEMPERATURE ESTIMATE:50 OK
TOTAL LOADCASES TIME: 500
ADAPTIVE:TEMPERATURE
PARAMETERS:
MAX # INCRENMENTS: 500
INITIAL TIME STEP: 1
OK
OK
17.8 定义作业
JOBS NEW
COUPLED
SELECTED:lcases 3
lcases 1
lcases 2
lcases 4
INITIAL LOADS: flux3(on)
film(on)
fix_xy(on)
fix_z(on)
CONTACT CONTROL
INITIAL CONTACT
CONTACT TABLE:ctable1
OK
JOB RESULTS
Stress(on)
Equivalent V on Mises Stress(on)
Total Equivalent Plastic Strain(on)
OK
OK
ELEMENT TYPE
COUPLED
3-D SOLID:117
OK
ALL:EXISTING
CHECK
RUN
17.9 温度场结果分析
第一层焊缝的温度场
焊接第二层第一道的温度场
第二层第二道的温度场。