L

⁐᥋ᵓ㐀ࢩ࣏ࣥࢪ࣒࢘ ㅮ₇ㄽᩥ㞟 ᖺ ᭶
㔜ྜ࣓ࢵࢩࣗἲࢆ⏝࠸ࡓ⌮᝿໬㝧ゎἲ )(0 ࡟ࡼࡿ⁐᥋ኚᙧ࣭ṧ␃ᛂຊゎᯒ
኱㜰ᗓ❧኱Ꮫ኱Ꮫ㝔
‫⏕ۑ‬ᓥ ୍ᶞ
ᰘཎ ṇ࿴
Analysis of Welding Distortions and Residual Stresses by Idealized Explicit FEM Using Mesh
Overlaying Technique
by Kazui IKUSHIMA and Masakazu SHIBAHARA
㸯㸬⥴ ゝ
⯪⯧ࡸᶫᱱࢆࡣࡌࡵ㸪໬ᏛࣉࣛࣥࢺࡸཎᏊຊࣉࣛࣥࢺ࡜࠸ࡗࡓᵝࠎ࡞〇ရࡢ〇㐀࡟⁐᥋ࡀᖜᗈࡃ⏝࠸ࡽࢀ࡚
࠸ࡿࡀ㸪⁐᥋ࡣ㸪ࡑࡢ᪋ᕤ࡟క࠸ᚲ↛ⓗ࡟Ⓨ⏕ࡍࡿኚᙧࡸṧ␃ᛂຊࡀၥ㢟࡜࡞ࡿࡇ࡜ࡀ࠶ࡿ㸬ࡑࡢࡓࡵ㸪⁐᥋
ࡢ᪋ᕤ๓࡟㸪〇ရ࡟⏕ࡌࡿ⁐᥋ኚᙧࡸṧ␃ᛂຊ࡟ࡘ࠸᳨࡚ウྍ⬟࡞ᡭἲࡀồࡵࡽࢀ࡚࠸ࡿ㸬
㠀⥺ᙧ᭷㝈せ⣲ἲ࡟ࡼࡿ⇕ᙎረᛶゎᯒࢆ⏝࠸ࡿࡇ࡜࡛㸪⁐᥋ኚᙧṧ␃ᛂຊࢆண ྍ⬟ 1)࡛࠶ࡿࡀ㸪⁐᥋ၥ㢟
ࡣᮦᩱࡢ⁐⼥ࢆྵࡴ㠀⥺ᙧᛶࡢᙉ࠸ၥ㢟࡛࠶ࡿࡇ࡜࠿ࡽ㸪ࡑࡢண ࡟ࡣ⭾኱࡞ィ⟬㈨※ࢆᚲせ࡜ࡍࡿ㸬ࡲࡓ㸪
㠀⥺ᙧ㡿ᇦࡀ⁐᥋ࢺ࣮ࢳ࿘㎶ࡢ⁐⼥㒊ࡢ㏆ഐ࡟㞟୰ࡍࡿࡇ࡜࠿ࡽ㸪⁐⼥㒊ࡢ࿘㎶ࡢヲ⣽࡞ࣔࢹࣝ໬ࡀᚲせ࡜࡞
ࡿ㸬ࡇࡢࡼ࠺࡞ࡇ࡜࠿ࡽ㸪⁐᥋ኚᙧ㸪ṧ␃ᛂຊࡢண ࡣィ⟬᫬㛫㸪࣓ࣔࣜᾘ㈝㔞ࡢ㠃࡛ゎᯒつᶍࡀ㝈ᐃࡉࢀ࡚
࠾ࡾ㸪ຍ࠼࡚㸪ゎᯒࣔࢹࣝࡢసᡂ࡟ேⓗ㸪᫬㛫ⓗࢥࢫࢺࢆせࡍࡿࡓࡵᅔ㞴࡜࡞ࡗ࡚࠸ࡿࡢࡀ⌧≧࡛࠶ࡿ㸬
⁐᥋ኚᙧ㸪ṧ␃ᛂຊゎᯒࡢィ⟬つᶍ࡟㛵ࡍࡿၥ㢟ࢆᨵၿࡍࡿࡓࡵ㸪ⴭ⪅ࡽࡣ⌮᝿໬㝧ゎἲ FEM ࡜࿧ࡤࢀࡿ኱
つᶍ㧗㏿ゎᯒᡭἲࡢ㛤Ⓨࢆ㐍ࡵ࡚ࡁࡓ 2)㸬⌮᝿໬㝧ゎἲ FEM ࡣ㸪ືⓗ㝧ゎἲ FEM3)ࢆᇶ࡟⁐᥋ၥ㢟࡟ᑐࡋ࡚ຠ
⋡໬ࢆᅗࡗࡓᡭἲ࡛࠶ࡾ㸪ᚑ᮶ᡭἲ࡜࡯ࡰྠ➼ࡢゎᯒ⢭ᗘࢆ᭷ࡋ㸪࠿ࡘ㸪ᚑ᮶ᡭἲ࡟ẚ࡭࡚㧗㏿㸪┬࣓ࣔࣜ࡜
࠸࠺≉ᚩࢆ᭷ࡋ࡚࠸ࡿ㸬ࡲࡓ㸪⌮᝿໬㝧ゎἲ FEM ࡣືⓗ㝧ゎἲ FEM ࢆᇶ࡟ࡋ࡚࠸ࡿࡓࡵ㸪୪ิ໬࡟ᑐࡋ࡚㠀
ᖖ࡟㐺ࡋ࡚࠾ࡾ㸪㏆ᖺ㸪୪ิᩘ್ィ⟬ࡢᐇ⾜⎔ቃ࡜ࡋ࡚ὀ┠ࡉࢀ࡚࠸ࡿ⏬ീฎ⌮⿦⨨(Graphics Processing Unit:
GPU)࡟ࡼࡿ୪ิ໬ࢆᑟධࡍࡿࡇ࡜࡛㸪୍ᒙࡢ㧗㏿໬ࢆᐇ⌧ࡋ㸪ᚑ᮶ᡭἲ࡛ࡣᅔ㞴࡞⛣ື⇕※ࢆ⪃៖ࡋࡓ 3 ḟඖ
ከᒙ⁐᥋ṧ␃ᛂຊゎᯒࢆᐇ⌧ࡋ࡚ࡁࡓ 4)㸬
୍᪉㸪ᵓ㐀ゎᯒ࡟࠾ࡅࡿゎᯒࣔࢹࣝసᡂࡢ㧗ᗘ໬࡟㈨ࡍࡿᡭἲ࡜ࡋ࡚㔜ྜ࣓ࢵࢩࣗἲࡀᥦ᱌ࡉࢀ࡚࠸ࡿ 5)㸬
㔜ྜ࣓ࢵࢩࣗἲࡣ㸪ゎᯒ㡿ᇦ඲యࡢせ⣲ศ๭࡟ᑐࡋ࡚㸪ヲ⣽࡞ゎᯒࢆᐇ᪋ࡋࡓ࠸⟠ᡤ࡟ヲ⣽࡞せ⣲ศ๭ࡢ࣓ࢵ
ࢩࣗࢆ㈞ࡾ௜ࡅࡿࡇ࡜࡛ゎᯒࡢ㧗⢭ᗘ໬࡜ࣔࢹࣝసᡂࡢ㧗ᗘ໬ࢆ㐩ᡂࡍࡿࡓࡵ࡟⪃᱌ࡉࢀࡓᡭἲ࡛࠶ࡿ㸬㔜ྜ
࣓ࢵࢩࣗἲࢆ⏝࠸࡚㸪ࡇࢀࡲ࡛࡟⥺ᙧᙎᛶゎᯒ 6)㸪ᙎረᛶゎᯒ 7)㸪⇕ఏᑟゎᯒ 8)㸪⇕ᙎᛶゎᯒ 9)㸪ࡁ⿣㐍ᒎ
ゎᯒ 10)࡞࡝ࡀᐇ᪋ࡉࢀ࡚࠸ࡿ㸬ࡲࡓ㸪ᵓ㐀඲యࡢࢩ࢙ࣝせ⣲࡟ᑐࡋ࡚㸪ࢯࣜࢵࢻせ⣲ࢆ㔜ྜࡉࡏࡿࡇ࡜࡛ࢬ࣮
࣑ࣥࢢゎᯒ࡟௦ࢃࡾヲ⣽࡞ゎᯒࢆᐇ᪋ࡋࡓ஦౛ࡶሗ࿌ࡉࢀ࡚࠸ࡿ 11)㸬⁐᥋ၥ㢟࡟࠾࠸࡚ࡣ㸪㠀⥺ᙧ㡿ᇦࡀࢺ࣮
ࢳ࿘㎶࡟㞟୰ࡍࡿࡇ࡜࠿ࡽ㸪㠀⥺ᙧ㡿ᇦࡢࣔࢹࣝ໬ࢆ㔜ྜ࣓ࢵࢩࣗἲ࡟ࡼࡾ⾜࠺ࡇ࡜ࡣ᭷ຠ࡛࠶ࡿ࡜⪃࠼ࡽࢀ
ࡿ㸬ࡋ࠿ࡋ࡞ࡀࡽ㸪㔜ྜ࣓ࢵࢩࣗἲࡣせ⣲ࢆ㔜ࡡྜࢃࡏࡿࡼ࠺࡞≉Ṧ࡞ฎ⌮ࢆᐇ᪋ࡍࡿࡇ࡜࠿ࡽ㸪඲య๛ᛶ࣐
ࢺࣜࢵࢡࢫࡢ㠀㞽ᡂศࡢศᕸࡀ୍⯡ⓗ࡞᭷㝈せ⣲ゎᯒ࡜ࡣ␗࡞ࡿࡓࡵ㸪ゎᯒ࡟せࡍࡿィ⟬᫬㛫ࡀ⭾኱࡜࡞ࡿࡇ
࡜ࡀሗ࿌ࡉࢀ࡚࠸ࡿ 12)㸬
ࡑࡇ࡛㸪ᮏ◊✲࡛ࡣ㸪ゎᯒࣔࢹࣝసᡂࡢຠ⋡໬࡜ゎᯒつᶍࡢྥୖࢆ┠ⓗ࡟㸪㔜ྜ࣓ࢵࢩࣗἲ࡟ᑐࡋ࡚⌮᝿໬
㝧ゎἲࢆᑟධࡋࡓᡭἲࡢ㛤Ⓨࢆヨࡳࡿ㸬㛤Ⓨᡭἲ࡟ࡘ࠸᳨࡚ドࡍࡿࡓࡵ࡟㸪ᇶ♏ⓗ࡞⁐᥋ၥ㢟࡟ᑐࡋ࡚㛤Ⓨᡭ
ἲࢆ㐺⏝ࡋ㸪ᚑ᮶ᡭἲ࡜ࡢẚ㍑ࢆ⾜࠺㸬ࡲࡓ㸪㛤Ⓨᡭἲࡢ᭷⏝ᛶࢆ♧ࡍࡓࡵ࡟㒊ᮦࡈ࡜࡟సᡂࡋࡓゎᯒࣔࢹࣝ
࡟ᑐࡋ࡚⁐᥋㒊ࢆࣔࢹࣝ໬ࡋࡓヲ⣽࣓ࢵࢩࣗࢆ㔜ྜࡉࡏ㸪㒊ᮦྠኈࡢ⤌❧⁐᥋ࢆ⾲⌧ࡍࡿゎᯒࢆᐇ᪋ࡍࡿ㸬
㸰㸬㔜ྜ࣓ࢵࢩࣗἲ࡟ࡼࡿ⁐᥋ኚᙧ࣭ṧ␃ᛂຊゎᯒࡢᐃᘧ໬
㸰㸬㸯 ⇕ఏᑟゎᯒࡢᐃᘧ໬
⁐᥋ኚᙧ㸪ṧ␃ᛂຊࡣ⇕ᙎረᛶゎᯒࢆ⾜࠺ࡇ࡜࡛ண ྍ⬟࡛࠶ࡿࡀ㸪⇕ᙎረᛶゎᯒ࡟ඛ❧ࡗ࡚ ᗘศᕸࡢᒚ
Ṕࡀᚲせ࡜࡞ࡿ㸬ᮏ⠇࡛ࡣ㸪ࡲࡎ㔜ྜ࣓ࢵࢩࣗἲࢆ⏝࠸ࡓ⇕ఏᑟゎᯒࡢᐃᘧ໬ࢆ⾜࠺㸬
⇕ఏᑟゎᯒࡢᨭ㓄᪉⛬ᘧ࡜ቃ⏺᮲௳ࡣ㸪ࡑࢀࡒࢀᘧ(1)㸪(2)࡛⾲ࡉࢀࡿ㸬
wT
w wT
cU
O
q in :
(1)
wt
wxi wx i
―301―
-301-
ΩG
Ω
ΩL
ΩL
ΓGL
Global mesh
(Rough mesh for the entire region)
Local mesh
(Detailed mesh near welding torch)
Analysis model
Fig. 1 Schematic illustration of analysis model for mesh overlaying method.
wT
D c T Tc on *
(2)
wn
ࡇࡇ࡛㸪 c 㸪 U 㸪 O 㸪 D c ࡣࡑࢀࡒࢀ㸪ẚ⇕㸪ᐦᗘ㸪⇕ఏᑟ⋡㸪⇕ఏ㐩ಀᩘ࡛࠶ࡾ㸪 T 㸪 Tc ࡣࡑࢀࡒࢀ ᗘ㸪ᐊ
㸪 q ࡣⓎ⇕ᐦᗘ㸪 : ࡣゎᯒ㡿ᇦ㸪 * ࡣ⇕ఏ㐩㠃ࢆ⾲ࡍ㸬
㔜ࡳ㛵ᩘࢆ T * ࡜ᐃ⩏ࡋ㸪ᨭ㓄᪉⛬ᘧ࡟ᑐࡋ࡚㔜ࡳ௜ࡁṧᕪἲࢆ㐺⏝ࡋ㸪ḟᘧࢆᚓࡿ㸬
wT
w wT ·
*§
*
(3)
³: T ¨¨© cU wt O wxi wxi ¸¸¹ d: ³: T q d*
㔜ྜ࣓ࢵࢩࣗἲ࡛ࡣ㸪Fig. 1 ࡟♧ࡍࡼ࠺࡟㸪ゎᯒ㡿ᇦ඲య : ࢆ⾲ࡍ࣓ࢵࢩࣗ(௨㝆㸪ࢢ࣮ࣟࣂ࣓ࣝࢵࢩࣗ࡜⛠
ࡍ)࡟ᑐࡋ࡚㸪ヲ⣽࡞せ⣲ศ๭ࡢ࣓ࢵࢩࣗ(௨㝆㸪࣮࣓ࣟ࢝ࣝࢵࢩࣗ࡜⛠ࡍ)ࢆ㡿ᇦ : L ࡟ᙇࡾ௜ࡅࡿࡇ࡜࡛ゎᯒ㡿
ᇦࢆ⾲⌧ࡍࡿ㸬ࡲࡓ㸪ࢢ࣮ࣟࣂ࣓ࣝࢵࢩࣗࡢࡳࡀᏑᅾࡍࡿ㡿ᇦࢆ : G : / : L ࡜ᐃ⩏ࡋ㸪: G ࡜ : L ࡢቃ⏺ࢆ * GL
࡜ࡍࡿ㸬ࡑࢀࡒࢀࡢ㡿ᇦ࡟࠾ࡅࡿ ᗘ࡟㛵ࡋ࡚㸪 : G ࡟࠾࠸࡚ࡣ㏻ᖖࡢ᭷㝈せ⣲ゎᯒ࡜ྠᵝ࡟㸪ᘧ(4)࡛⾲ࡉࢀ
ࡿ㛵ᩘࢆ⏝࠸࡚ ᗘሙࢆ㏆ఝࡍࡿ㸬୍᪉㸪 : L ࡟࠾࠸࡚ࡣ㸪ᘧ(5)࡟ࡼࡾ ᗘሙࢆ㏆ఝࡍࡿ㸬ࡲࡓ : G ࡜ : L ࡢቃ
⏺࡟࠾࠸࡚ࡣ㸪ᘧ(6)ࡢࡼ࠺࡟࣮࣓ࣟ࢝ࣝࢵࢩࣗࡢ ᗘ࡟ᣊ᮰᮲௳ࢆ୚࠼ࡿ㸬ࡇࢀࡣࢢ࣮ࣟࣂ࣓ࣝࢵࢩࣗ࡜࣮ࣟ
࣓࢝ࣝࢵࢩ࡛ࣗ ᗘሙࡢ㐃⥆ᛶࢆᢸಖࡍࡿࡓࡵࡢࡶࡢ࡛࠶ࡿ㸬
(4)
T N G T Gn in : G
> @^ `
(5)
T >N @^T ` >N @^T ` in :
(6)
^T ` 0 on *
ࡇࡇ࡛㸪>N @ 㸪>N @ ࡣࡑࢀࡒࢀࢢ࣮ࣟࣂ࣓ࣝࢵࢩࣗࡢᙧ≧㛵ᩘ㸪࣮࣓ࣟ࢝ࣝࢵࢩࣗࡢᙧ≧㛵ᩘ࡛࠶ࡾ㸪^T `㸪
^T `ࡣࡑࢀࡒࢀࢢ࣮ࣟࣂ࣓ࣝࢵࢩࣗ࡜࣮࣓ࣟ࢝ࣝࢵࢩࣗ࡟࠾ࡅࡿ⠇Ⅼ ᗘ࡛࠶ࡿ㸬ᘧ(5)࡟♧ࡍࡼ࠺࡟㸪 : ࡟
G
Gn
L
Ln
Ln
L
GL
G
Gn
L
Ln
L
࠾࠸࡚ࡣ㸪ࢢ࣮ࣟࣂ࣓ࣝࢵࢩࣗࡢ㏆ఝ㛵ᩘ࡟ᑐࡋ࡚㸪࣮࣓ࣟ࢝ࣝࢵࢩࣗࡢ㏆ఝ㛵ᩘࢆ㔜ࡡྜࢃࡏࡿᙧ࡛ ᗘሙ
ࡢ㏆ఝ㛵ᩘࢆసᡂࡍࡿ㸬ࡲࡓ㸪㔜ࡳ㛵ᩘ࡟㛵ࡋ࡚ࡶ㸪 ᗘሙ࡜ྠᵝࡢ㛵ᩘࢆ⏝࠸࡚ḟᘧ࡟ࡼࡾ㏆ఝࡍࡿ㸬
>N @^T ` in :
>N @^T ` >N @^T `
G
T*
*Gn
* Gn
G
T*
G
L
*Ln
(7)
(8)
in : L
ᘧ(4)-(8)ࢆᘧ(3)࡟௦ධࡋ㸪㒊ศ✚ศ࠾ࡼࡧቃ⏺᮲௳ࢆ㐺⏝ࡍࡿࡇ࡜࡛ḟᘧࢆᚓࡿ㸬
>C @ w T Gn >K @ T Gn >A@ T Gn ^Q`
(9)
wt
ªC GG C GL º w ­T Gn ½ ª K GG K GL º ­T Gn ½ ª AGG AGL º ­T Gn ½ ­Q G ½
(10)
¾ «
¾ «
¾® ¾
»®
»®
« LG
» ®
C LL ¼ wt ¯T Ln ¿ ¬ K LG K LL ¼ ¯T Ln ¿ ¬ ALG ALL ¼ ¯T Ln ¿ ¯Q L ¿
¬C
ࡇࡇ࡛㸪ᘧ(9)ࡣ㡿ᇦ : G ࡟ᑐᛂࡍࡿ᪉⛬ᘧ࡛࠶ࡾ㸪ಀᩘ࣐ࢺࣜࢵࢡࢫ࠾ࡼࡧᐃᩘ࣋ࢡࢺࣝࡣ㏻ᖖࡢ᭷㝈せ⣲ἲ
࡜ྠ➼ࡢᡭ㡰࡛ᑟฟࡉࢀࡿ㸬୍᪉㸪ᘧ(10)ࡣ㡿ᇦ : L ࡟ᑐᛂࡍࡿ᪉⛬ᘧ࡛࠶ࡾ㸪C ab 㸪K ab 㸪Aab 㸪Q a a, b : G, L
ࡣࡑࢀࡒࢀ⇕ᐜ㔞࣐ࢺࣜࢵࢡࢫ㸪⇕ఏᑟ࣐ࢺࣜࢵࢡࢫ㸪⇕ఏ㐩࣐ࢺࣜࢵࢡࢫ㸪࠾ࡼࡧ㸪Ⓨ⇕㔞࣋ࢡࢺ࡛ࣝ࠶ࡾ㸪
௨ୗࡢ✚ศ࡛୚࠼ࡽࢀࡿ㸬
^ `
^ `
^ `
> @ > @ > @^ `
>C @ ³
ab
:L
> @ >N @d:
cU N a
T
a
a, b : G, L
b
T
(11)
b
>K @ ³ O ª« wwNx º» ª« wwNx º»d: a, b : G, L
«¬
»¼ «¬
»¼
>A @ ³ D >N @ >N @d* a, b : G, L
^Q ` ³ q >N @ d: ³ D T >N @ d: a : G, L
ab
:L
ab
*L
i
a T
c
b
a T
a
:L
(12)
i
*L
c
c
a T
―302―
-302-
(13)
(14)
඲య㡿ᇦ : :G : L ࡟࠾ࡅࡿ᪉⛬ᘧࢆᑟฟࡍࡿࡓࡵ㸪௨ୖࡢᡭ㡰࡛ồࡲࡿ༙㞳ᩓ໬ᘧ(9)࠾ࡼࡧ(10)ࡢ࿴ࢆ
ྲྀࡾ㸪ゎᯒ㡿ᇦ඲యࡢ༙㞳ᩓ໬ᘧࢆᚓࡿ㸬ࡲࡓ㸪⁐᥋⌧㇟࡟࠾࠸࡚ࡣຍ⇕୰ࡢ ᗘኚ໬ࡣᛴᓧ࡛࠶ࡿࡶࡢࡢ㸪
෭༷㐣⛬࡟࠾࠸࡚ࡣᩘ༑ศ࠿ࡽᩘ᫬㛫ࢆ࠿ࡅ࡚⦆ࡸ࠿࡟᏶඲෭༷࡟⮳ࡿࡇ࡜ࢆ⪃៖ࡋ㸪᫬㛫ቑศ࡟㛵ࡋ࡚ẚ㍑
ⓗ⮬⏤࡟タᐃࡀྍ⬟࡞㝜ⓗ࡞㞳ᩓ໬ࢆ⾜࠺㸬ᮏᐃᘧ໬࡟࠾࠸࡚ࡣ Crank-Nicolson ἲࢆ⏝࠸ࡿࡶࡢ࡜ࡋࡓ㸬ࡲࡓ㸪
ᘧ(11)-(14)ࡢ✚ศࡣ㸪࢞࢘ࢫ✚ศࢆ⏝࠸࡚ᩘ್ⓗ࡟⾜࠺ࡀ㸪ࡑࡢ㝿࡟㸪࣮࣓ࣟ࢝ࣝࢵࢩࣗࡢ࢞࢘ࢫ✚ศⅬ࡟࠾ࡅ
ࡿࢢ࣮ࣟࣂ࣓ࣝࢵࢩࣗࡢᙧ≧㛵ᩘ࠾ࡼࡧࡑࡢ໙㓄ࡀᚲせ࡜࡞ࡿ㸬ᮏ◊✲࡛ࡣ㸪ᩥ⊩ 11)ࢆཧ⪃࡟㸪࣮࣓ࣟ࢝ࣝࢵ
ࢩࣗࡢ࢞࢘ࢫ✚ศⅬࡢ඲యᗙᶆ⣔࡛ࡢ఩⨨ᗙᶆࡼࡾ㸪࣮࣓ࣟ࢝ࣝࢵࢩࣗࡢ࢞࢘ࢫ✚ศⅬࡢࢢ࣮ࣟࣂ࣓ࣝࢵࢩࣗ
࡟࠾ࡅࡿせ⣲ෆᗙᶆ⣔ࢆゎᯒࡢ㛤ጞ๓࡟⟬ฟࡋ㸪✚ศ᫬࡟㏲ḟཧ↷ࡍࡿࡇ࡜࡛㸪࣮࣓ࣟ࢝ࣝࢵࢩࣗࡢ࢞࢘ࢫ✚
ศ᫬࡟ࢢ࣮ࣟࣂ࣓ࣝࢵࢩࣗࡢᙧ≧㛵ᩘ࠾ࡼࡧࡑࡢ໙㓄ࢆỴᐃࡍࡿࡶࡢ࡜ࡋࡓ㸬
㸰㸬㸰 ⇕ᙎረᛶゎᯒࡢᐃᘧ໬
⇕ᙎረᛶゎᯒ࡟࠾࠸࡚ࡣ㸪๓⠇࡟࠾࠸࡚ᐃᘧ໬ࢆ⾜ࡗࡓ⇕ఏᑟゎᯒ࡟ࡼࡾᚓࡽࢀࡿ ᗘሙࡢᒚṔࢆཧ↷ࡋྛ
᫬้࡟࠾ࡅࡿኚ఩ቑศࢆồࡵࡿ㸬ኚ఩ቑศ࡟㛵ࡍࡿ௬᝿௙஦ࡢཎ⌮ࡣḟᘧ࡛୚࠼ࡽࢀࡿ㸬࡞࠾㸪ᮏᐃᘧ໬࡟࠾
࠸࡚ࡣ㸪እ㒊Ⲵ㔜ࡣ⪃៖ࡋ࡞࠸ࡶࡢ࡜ࡋࡓ㸬
T
³: ^GH ` ^V ` ^'V `d:
0
G
(15)
ࡇࡇ࡛㸪 ^GH ` 㸪 ^V ` 㸪 ^'V `ࡣࡑࢀࡒࢀ௬᝿ࡦࡎࡳ㸪ᛂຊ࠾ࡼࡧᛂຊቑศ࡛࠶ࡿ㸬
ኚ఩ቑศ࡜ࡦࡎࡳቑศࢆḟᘧࡢ㏻ࡾᐃ⩏ࡍࡿ㸬
^'u`
^'u`
^'u `
>N @^'u ` in :
>N @^'u ` >N @^'u `
Ln
G
Gn
G
Gn
0 on *
G
L
Ln
(16)
in :
L
(17)
GL
(18)
(19)
>B @^'u ` in :
(20)
>B @^'u ` >B @^'u ` in :
ࡇࡇ࡛㸪>N @㸪>N @ 㸪>B @ 㸪 >B @ ࡣࡑࢀࡒࢀࢢ࣮ࣟࣂ࣓ࣝࢵࢩࣗ࠾ࡼࡧ࣮࣓ࣟ࢝ࣝࢵࢩࣗ࡟࠾ࡅࡿᙧ≧㛵ᩘ࠾
ࡼࡧኚ఩ࡦࡎࡳ࣐ࢺࣜࢵࢡࢫ࡛࠶ࡾ㸪 ^'u `㸪 ^'u ` ࡣࡑࢀࡒࢀࢢ࣮ࣟࣂ࣓ࣝࢵࢩࣗ࠾ࡼࡧ࣮࣓ࣟ࢝ࣝࢵࢩࣗ
^'H `
^'H `
G
Gn
G
Gn
G
L
G
L
G
Ln
L
L
Gn
Ln
࡟࠾ࡅࡿ⠇Ⅼኚ఩ቑศ࡛࠶ࡿ㸬
ࢢ࣮ࣟࣂ࣓ࣝࢵࢩࣗ࠾ࡼࡧ࣮࣓ࣟ࢝ࣝࢵࢩࣗ࡟࠾ࡅࡿ⠇Ⅼ௬᝿ኚ఩ࢆࡑࢀࡒࢀ Gu Gn 㸪 Gu Ln ࡜ࡋ㸪ࡦࡎࡳቑ
ศ࡜ྠᵝࡢᙧ࡛ḟᘧ࡟ࡼࡾ௬᝿ࡦࡎࡳࢆᐃ⩏ࡍࡿ㸬
^ ` ^ `
^GH `
^GH `
>B @^Gu ` in :
>B @^Gu ` >B @^Gu `
G
Gn
G
Gn
G
L
Ln
(21)
in :
L
(22)
ᛂຊቑศࡣḟᘧ࡟ࡼࡾᐃ⩏ࡍࡿ㸬
(23)
>D @^'H ` ^'H ` in :
(24)
>D @^'H ` ^'H ` ^'H ` ^'H ` in :
ࡇࡇ࡛㸪>D @ 㸪>D @ ࡣࡑࢀࡒࢀࢢ࣮ࣟࣂ࣓ࣝࢵࢩࣗ㸪࣮࣓ࣟ࢝ࣝࢵࢩࣗ࡟࠾ࡅࡿᛂຊࡦࡎࡳ࣐ࢺࣜࢵࢡࢫ㸪^'H `㸪
^'H `ࡣࡑࢀࡒࢀࢢ࣮ࣟࣂ࣓ࣝࢵࢩࣗ࡟࠾ࡅࡿᗄఱᏛࡦࡎࡳቑศ㸪 ᗘࡦࡎࡳቑศ㸪 ^'H `㸪 ^'H `㸪 ^'H `ࡣ
^'V `
^'V `
G
G
G
G
T
L
G
L
G
L
P
L
T
L
G
L
G
T
L
L
P
L
T
ࡑࢀࡒࢀ࣮࣓ࣟ࢝ࣝࢵࢩࣗ࡟࠾ࡅࡿᗄఱᏛࡦࡎࡳቑศ㸪ረᛶࡦࡎࡳቑศ㸪⇕ࡦࡎࡳቑศࢆ⾲ࡍ㸬࡞࠾㸪ᮏᐃᘧ
໬࡛ࡣ㸪㠀⥺ᙧࡢረᛶኚᙧࡣ : L ࡢࡳ࡛⏕ࡌࡿࡶࡢ࡜ࡋ㸪 : G ࡟࠾࠸࡚ࡣᙎᛶኚᙧ࡜⇕ኚᙧࡢࡳࢆ⪃៖ࡋࡓ㸬
ᘧ(19)-(24)ࢆᘧ(15)࡟௦ධࡋḟᘧࢆᚓࡿ㸬
>K @^'u Gn ` ^'F` ^f `
GG
GL
(25)
Gn
G
G
ªK
K º ­'u ½ ­'F ½ ­ f ½
(26)
¾ ®
¾® ¾
« LG
»®
K LL ¼ ¯'u Ln ¿ ¯ 'F L ¿ ¯ f L ¿
¬K
ࡇࡇ࡛㸪ᘧ(25)ࡣ㡿ᇦ : G ࡟ᑐᛂࡍࡿ᪉⛬ᘧ࡛࠶ࡾ㸪๓⠇ࡢ⇕ఏᑟゎᯒ࡜ྠᵝ࡟㸪㏻ᖖࡢ᭷㝈せ⣲ゎᯒ࡜ྠࡌᡭ
⥆ࡁ࡟ࡼࡾ๛ᛶ࣐ࢺࣜࢵࢡࢫ >K @ 㸪Ⲵ㔜ቑศ࣋ࢡࢺࣝ ^'F ` ࠾ࡼࡧ⠇Ⅼෆຊ࣋ࢡࢺࣝ ^ f ` ࢆồࡵࡿ㸬୍᪉㸪ᘧ(26)
ࡣ㡿ᇦ : L ࡟ᑐᛂࡍࡿ᪉⛬ᘧ࡛࠶ࡾ㸪ྛ㡯ࡣ௨ୗࡢ✚ศ࡟ࡼࡾィ⟬ࡉࢀࡿ㸬
>K @ ³ >B @ >D @>B @d: a, b : G, L
^'F ` ³ >B @ >D @ ^'H `d: a : G, L
^f ` ³ >B @ ^V `d: a : G, L
a T
ab
L
b
(27)
:L
a T
a
L
:L
a T
a
L
T
(28)
L
(29)
:L
඲య๛ᛶ᪉⛬ᘧࡣᘧ(25)㸪(26)ࡢ࿴ࢆྲྀࡿࡇ࡜࡛ᚓࡽࢀ㸪඲యࡀ㟼ⓗᖹ⾮≧ែ࡟཰᮰ࡍࡿࡲ࡛ồゎࢆ⧞ࡾ㏉ࡍ㸬
―303―
-303-
㸰㸬㸱 ⌮᝿໬㝧ゎἲࡢᑟධ
๓⠇ࡢ㏻ࡾ㸪⇕ఏᑟゎᯒ࡟㛵ࡋ࡚ࡣᘧ(9)࠾ࡼࡧᘧ(10)㸪⇕ᙎረᛶゎᯒ࡟㛵ࡋ࡚ࡣᘧ(25)㸪(26)ࡢ㐃❧᪉⛬ᘧࢆ
᫬㛫ࢫࢸࢵࣉẖ࡟㏲ḟồゎࡍࡿࡇ࡜࡛ゎࡀᚓࡽࢀࡿ㸬ࡋ࠿ࡋ࡞ࡀࡽ㸪㔜ྜ࣓ࢵࢩࣗἲ࡟࠾࠸࡚ࡣ㸪㏻ᖖࡢ᭷㝈
せ⣲ἲ࡜ࡣ␗࡞ࡾ㸪㐃❧᪉⛬ᘧࡢಀᩘ⾜ิࡢ㠀㞽ᡂศࡢศᕸࡀ Fig. 2 ࡟♧ࡍࡼ࠺࡞ᙧ࡜࡞ࡿࡓࡵ㸪ᵓ㐀ゎᯒ࡟
࠾࠸࡚⏝࠸ࡽࢀࡿࡇ࡜ࡢከ࠸┤᥋ἲࢆ⏝࠸࡚㐃❧᪉⛬ᘧࢆồゎࡍࡿ㝿࡟ Fill-in ࡀ⏕ࡌࡸࡍࡃ㸪ィ⟬᫬㛫ࡸ࣓ࣔ
ࣜᾘ㈝㔞ࡢቑ኱࡟ࡘ࡞ࡀࡿ㸬ࡇࡢၥ㢟࡟ᑐࡋ࡚㸪඲య๛ᛶ࣐ࢺࣜࢵࢡࢫࡢ␯ᛶࢆ฼⏝ࡋ࡚ࢫࣃ࣮ࢫࢯࣝࣂ࣮13)
ࢆ౑⏝ࡍࡿ᪉ἲ㸪Fill-in ࡀᑡ࡞ࡃ࡞ࡿࡼ࠺⠇Ⅼ␒ྕࢆ᭱㐺໬ࡍࡿ᪉ἲ 14)ࡸ㸪ࢢ࣮ࣟࣂ࣓ࣝࢵࢩࣗ࡜࣮࣓ࣟ࢝ࣝ
ࢵࢩࣗࢆูࠎ࡟ồゎࡋ᭱⤊ⓗ࡟㡿ᇦ඲యࡀ཰᮰ࡍࡿࡲ࡛཯᚟ࡍࡿࡼ࠺࡞ᡭἲ 15)ࡀ⪃࠼ࡽࢀࡿࡀ㸪ᮏ◊✲࡟࠾࠸
࡚ࡣ㸪⌮᝿໬㝧ゎἲࢆ㐺⏝ࡍࡿࡇ࡜࡛ィ⟬᫬㛫࡜࣓ࣔࣜᾘ㈝㔞ࡢ๐ῶࢆヨࡳࡿ㸬
⌮᝿໬㝧ゎἲ FEM ࡟ࡼࡿ⇕ఏᑟゎᯒ࠾ࡼࡧ⇕ᙎረᛶゎᯒࡣࡑࢀࡒࢀᩥ⊩ 2, 16)࡟࠾࠸࡚ヲ⣽࡟㏙࡭ࡽࢀ࡚࠸ࡿ㸬
ࡋ࠿ࡋ࡞ࡀࡽ㸪⌮᝿໬㝧ゎἲࢆ㐺⏝ࡍࡿሙྜ㸪཰᮰ࡍࡿࡲ࡛ࡢ᫬㛫ࢫࢸࢵࣉࡢィ⟬࡟࠾࠸࡚ᘧ(26)ྑ㎶ࡢ✚ศ᧯
సࢆ⧞ࡾ㏉ࡍᚲせࡀ࠶ࡾ㸪཰᮰ࡍࡿࡲ࡛࡟ᩘⓒࢫࢸࢵࣉ⛬ᗘࢆせࡍࡿ㸬ᘧ(26)ྑ㎶ࡢ✚ศࡣ࣮࣓ࣟ࢝ࣝࢵࢩࣗෆ
ࡢせ⣲࡟࠾࠸࡚ࢢ࣮ࣟࣂ࣓ࣝࢵࢩࣗෆࡢせ⣲ࡢኚ఩ࡦࡎࡳ࣐ࢺࣜࢵࢡࢫࢆཧ↷ࡍࡿࡼ࠺࡞」㞧࡞᧯సࢆక࠺ࡓ
ࡵ㸪㏻ᖖࡢ✚ศ࡟ẚ࡭࡚ィ⟬㔞ࡢቑຍࡀぢ㎸ࡲࢀࡿ㸬ࡑࡢࡓࡵ㸪㔜ྜ࣓ࢵࢩࣗἲ࡟ᑐࡋ࡚⌮᝿໬㝧ゎἲࢆࡑࡢ
ࡲࡲ㐺⏝ࡍࡿሙྜ㸪㠀ຠ⋡࡞ゎᯒ࡟࡞ࡿᜍࢀࡀ࠶ࡿ㸬
ࡑࡇ࡛㸪ᮏ◊✲࡛ࡣ㸪Fig. 3 ࡟♧ࡍࡼ࠺࡞ᡭἲࢆ᥇ࡿ㸬ࡲࡎ㸪㉁㔞࣐ࢺࣜࢵࢡࢫ㸪ῶ⾶࣐ࢺࣜࢵࢡࢫࢆィ⟬ࡋ㸪
ྜࢃࡏ࡚๛ᛶ࣐ࢺࣜࢵࢡࢫࢆ⟬ฟࡍࡿ㸬ࡇࡇ࡛㸪๛ᛶ࣐ࢺࣜࢵࢡࢫ࡟㛵ࡋ࡚ࡣ㸪ᅽ⦰⾜᱁⣡᪉ᘧࡢ␯⾜ิࡢᙧ
࡛ಖᏑࡍࡿ㸬⥆࠸࡚㸪ືⓗ㝧ゎἲ࡟ᇶ࡙ࡁ᫬㛫ࢫࢸࢵࣉࢆ㐍ࡵࡿࡇ࡜࡛ኚ఩ࢆồࡵ㸪ᘧ(25)㸪(26)ࡢྑ㎶ࡢ✚ศ
ࡢ௦ࢃࡾ࡟㸪ồࡵࡓኚ఩࡜๛ᛶ࣐ࢺࣜࢵࢡࢫࡢ✚ࡼࡾṧᕪຊ࣋ࢡࢺࣝࢆ⟬ฟࡍࡿ㸬ᣦᐃࡋࡓ᫬㛫ࢫࢸࢵࣉᩘࡢ
ศ(N ᅇ)ࡔࡅኚ఩ࡢ⟬ฟ࡜ṧᕪຊࡢ⟬ฟࢆ⧞ࡾ㏉ࡋࡓࡢࡕ㸪ᘧ(25)㸪ᘧ(26)ࡢྑ㎶ࡢ✚ศࢆᐇ⾜ࡋṇ☜࡞ṧᕪຊ
࣋ࢡࢺࣝࢆ⟬ฟࡋ㸪㡿ᇦ඲యࡀ㟼ⓗᖹ⾮≧ែ࡟㐩ࡋ࡚࠸ࡿ࠿ࢆ☜ㄆࡍࡿ㸬ࡇࡇ࡛㸪㟼ⓗᖹ⾮≧ែࡀᚓࡽࢀࡓሙ
ྜ㸪ḟࡢ ᗘࢫࢸࢵࣉࡢィ⟬࡟⛣ࡾ㸪㟼ⓗᖹ⾮≧ែࡀᚓࡽࢀ࡚࠸࡞࠸ሙྜ㸪ṧᕪຊ࣋ࢡࢺࣝࢆⲴ㔜࣋ࢡࢺࣝ࡜
ࡋ࡚㈇Ⲵࡋ㸪෌ᗘ᫬㛫ࢫࢸࢵࣉࡢィ⟬ࢆ⾜࠺㸬௨ୖࡢᡭἲࢆ⏝࠸ࡿࡇ࡜࡛㸪」㞧࡞✚ศࢆ⾜࠺ᅇᩘࢆ๐ῶࡋ㸪
ィ⟬ࡢຠ⋡໬ࢆᅗࡿ㸬࡞࠾㸪Fig. 3 ࡛ࡣ⇕ᙎረᛶゎᯒ࡟ࡘ࠸࡚♧ࡋࡓࡀ㸪⇕ఏᑟゎᯒ࡟࠾࠸࡚ࡶᘧ(9)㸪(10)ࢆᇶ
࡟ྠᵝࡢᡭ㡰࡛ゎᯒࢆᐇ᪋ࡍࡿ㸬
Start
㸱㸬ᇶ♏ⓗ⁐᥋ၥ㢟࡬ࡢ㐺⏝࡟ࡼࡿ㛤Ⓨᡭἲࡢ᳨ド
㸱㸬㸯 ゎᯒࣔࢹࣝ࠾ࡼࡧ᮲௳
㛤Ⓨᡭἲࢆ Fig. 4 ࡟♧ࡍᇶ♏ⓗ࡞ࣅ࣮ࢻ࢜ࣥࣉ࣮ࣞࢺၥ㢟࡟
ᑐࡋ࡚㐺⏝ࡋ㸪ᚑ᮶ᡭἲ࡟ࡼࡿゎᯒ࡜ẚ㍑ࡍࡿࡇ࡜࡛㸪㛤Ⓨᡭ
ἲࡢ᳨ドࢆ⾜࠺㸬ᮏゎᯒࣔࢹࣝࡣᯈ㛗 100 mm㸪ᯈᖜ 100 mm㸪
ᯈཌ 10mm ࡢᯈᮦࢆᶍᨃࡋ࡚࠾ࡾ㸪⁐᥋⥺ࡣᯈᖜ᪉ྥࡢ୰ኸ⥺
ࢆ௬ᐃࡋ㸪ၥ㢟ࡢᑐ⛠ᛶࡼࡾᯈᖜ᪉ྥ࡟༙ศࡢࡳࢆࣔࢹࣝ໬ࡋ
ࡓ㸬⁐᥋᮲௳ࡣ㸪㟁㏻ 120 A㸪㟁ᅽ 10 V㸪⁐᥋㏿ᗘ 4.0 mm/s㸪
⇕ຠ⋡ 0.5 ࢆ௬ᐃࡋࡓ㸬ᖹᯈࡣ㌾㗰ᮦࢆ௬ᐃࡋ㸪Fig. 5 ࡟♧ࡍᮦ
ᩱᐃᩘࡢ ᗘ౫Ꮡᛶࢹ࣮ࢱࢆゎᯒ࡟౑⏝ࡋࡓ㸬ゎᯒ࡟⏝࠸ࡓせ
⣲ศ๭ࢆ Fig. 6 ࡟♧ࡍ㸬ྠᅗ(a)ࡣࢢ࣮ࣟࣂ࣓ࣝࢵࢩࣗࡢせ⣲ศ
๭࡛࠶ࡾ㸪ࡣẚ㍑ⓗ⢒࠸せ⣲ศ๭ࢆ⾜࠸ 400 せ⣲࡜ࡋࡓ㸬ࡲࡓ㸪
࣮࣓ࣟ࢝ࣝࢵࢩࣗࡢせ⣲ศ๭ࢆྠᅗ(b)࡟♧ࡍ㸬࣮࣓ࣟ࢝ࣝࢵࢩ
ࣗ࡟࠾࠸࡚ࡣ㠀⥺ᙧᣲືࢆゎᯒࡍࡿࡓࡵヲ⣽࡞せ⣲ศ๭ࢆ⾜࠸
10,620 せ⣲࡜ࡋࡓ㸬ᚑ᮶ᡭἲࡢゎᯒ࡟⏝࠸ࡓせ⣲ศ๭ࡣ Fig. 7
Renew temperature field
Compute [M], [C], [K], {ΔF}
{F} ←{ΔF}, {U} ← 0, t ← 0
Convergence loop
Compute displacement {u}
by explicit FEM
t←t+1
Compute unbalanced force
vector by {F} - [K]{u}
t<N?
No
t←0
{F} ← {R}
{u} ← 0
Yes
{U} ← {U} + {u}
[KGG]
GG
ªK
« LG
¬K
GL
K º
»
K LL ¼
[KGL]
Half
band
width
Compute unbalanced force vector {R}
by RHS of Eq. (25), (26) using {U}
Static equilibrium state?
[KLG]
[KLL]
Zero components
No
Yes
No
Welding finished?
Non-zero components
Yes
Fig. 2 Schematic illustration of non-zero components of
stiffness matrix in mesh overlaying method.
―304―
-304-
End
Fig. 3 Flow of developed method.
10.0
F
A㼿
D
10 mm
A
Torch
Physical constants
8.0
C
B
Density (㼤10-3 g/mm3)
Yielding stress
(㼤102 MPa)
6.0
Specific heat
(㼤10-1 J/g/rC)
2.0
E
0.0
Fig. 4 Bead-on-plate analysis model.
Poisson’s ratio
(㼤10-1)
Heat conductivity
(㼤10-1 J/mm/s/rC)
4.0
Thermal expansion (㼤10-1 /rC)
Young’s modulus (㼤105 MPa)
0.0
300.0
600.0
900.0
Temperature (Υ)
1200.0
1500.0
Fig. 5 Temperature dependent material properties.
((a)) Global
Gl b l mesh.
h
(b) Local me
mesh.
(c) Analysis model.
(overlaid)
Fig. 6 FE mesh divis
Fig
divisions for developed method.
Fig. 7 FE mesh
h di
divisions
ii
ffor existing
i i method.
h d
࡟♧ࡍ㏻ࡾ࡛࠶ࡾ㸪せ⣲ᩘࡣ 11,970 ࡛࠶ࡿ㸬ẚ㍑ᑐ㇟࡜ࡋ࡚㸪⇕ఏᑟゎᯒ࡟㛵ࡋ࡚ࡣ㸪㝜ゎἲ FEM㸪⇕ᙎረᛶ
ゎᯒ࡟㛵ࡋ࡚ࡣ㸪㟼ⓗ㝜ゎἲ FEM ࢆ⏝࠸㸪ࡑࢀࡒࢀࡢᡭἲ࡟࠾࠸࡚㸪㐃❧᪉⛬ᘧࡢồゎ࡟ࡣࢫ࢝࢖ࣛ࢖ࣥἲࢆ
⏝࠸ࡓ㸬࡞࠾㸪๓❶࡛♧ࡋࡓ✚ศ᧯స࡟ࡼࡾṧᕪ࣋ࢡࢺࣝࢆ⟬ฟࡍࡿ᫬㛫ࢫࢸࢵࣉᩘ N ࡟㛵ࡋ࡚㸪ᮏゎᯒ࡛ࡣ
N = 200 ࡜ࡋࡓ㸬⇕ᙎረᛶゎᯒ࡟࠾࠸࡚㸪ṧᕪຊ࣋ࢡࢺࣝࡢ 2 ஌ࣀ࣒ࣝ࡜⠇Ⅼ཯ຊ࣋ࢡࢺࣝࡢ 2 ஌ࣀ࣒ࣝࡢẚࡀ
10㸫3 ௨ୗ࡟࡞ࡗࡓሙྜ࡟཰᮰ࡋࡓࡶࡢ࡜ࡋࡓ㸬
㸱㸬㸰 ᚑ᮶ᡭἲ࡜ࡢẚ㍑࡟ࡼࡿ⇕ఏᑟゎᯒࡢ᳨ド
Fig. 8 ࡟᭱㧗฿㐩 ᗘศᕸࢆ♧ࡍ㸬ྠᅗࡼࡾ㸪୧ᡭἲ࡟ࡼࡿ᭱㧗฿㐩 ᗘศᕸࡀᐃᛶⓗ࡟୍⮴ࡋ࡚࠸ࡿࡇ࡜ࡀ
☜ㄆ࡛ࡁࡿ㸬ࡲࡓ㸪Fig. 9 ࡟ᖹᯈୖ㠃ࡢ⁐᥋⥺୰ኸᶓ᩿㠃࡟࠾ࡅࡿ A-A’⥺ୖࡢ᭱㧗฿㐩 ᗘศᕸࡢẚ㍑ࢆ♧ࡍ㸬
ྠᅗࡼࡾ㸪ᮏᡭἲ࡜㝜ゎἲ FEM ࡢ᭱㧗฿㐩 ᗘศᕸࡣ㸪ᐃ㔞ⓗ࡟୍⮴ࡋ࡚࠸ࡿࡇ࡜ࡀ☜ㄆ࡛ࡁࡿ㸬≉࡟㸪ࢢࣟ
࣮ࣂ࣓ࣝࢵࢩࣗ࡜࣮࣓ࣟ࢝ࣝࢵࢩࣗࡢቃ⏺࡟࠾࠸࡚ࡶ㸪㐃⥆ⓗ࡞ ᗘศᕸ࡜࡞ࡗ࡚࠸ࡿࡇ࡜ࡀศ࠿ࡿ㸬Fig. 10
࡟⁐᥋㛤ጞ࠿ࡽ 50 ⛊ᚋࡲ࡛ࡢ Fig. 4 ࡟♧ࡍⅬ B㸪C㸪D ࡟࠾ࡅࡿ㐣Ώ ᗘᒚṔࢆ♧ࡍ㸬Fig. 10 ࡼࡾ㸪 ᗘᒚṔ
࡟㛵ࡋ࡚ࡶ㸪㛤Ⓨᡭἲ࡜ᚑ᮶ᡭἲࡢゎᯒ⤖ᯝࡣ࡯ࡰ୍⮴ࡋ࡚࠸ࡿࡇ࡜ࡀศ࠿ࡿ㸬
㸱㸬㸱 ᚑ᮶ᡭἲ࡜ࡢẚ㍑࡟ࡼࡿ⇕ᙎረᛶゎᯒࡢ᳨ド
Fig. 11 ࡟㛤Ⓨᡭἲ࡜ᚑ᮶ᡭἲ࡟ࡼࡿᶓ཰⦰ศᕸࡢẚ㍑ࢆ♧ࡍ㸬Fig. 11 ࡼࡾ㸪㛤Ⓨᡭἲ࡜ᚑ᮶ᡭἲࡢᶓ཰⦰ࡣ
࡯ࡰྠ➼ࡢศᕸࢆ᭷ࡋ࡚࠸ࡿࡇ࡜ࡀ☜ㄆ࡛ࡁࡿ㸬ྠᵝ࡟㸪Fig. 12 ࡟㸪⁐᥋⥺᪉ྥ୰ኸᶓ᩿㠃ୖ࡟࠾ࡅࡿ㠃እ᪉
(rC)
2000.0
1800.0
1600.0
1400.0
1200.0
1000.0
800.0
600.0
y
400.0
200.0
0.0
z
x
(a) Existing method.
(b) Developed method.
Fig. 8 Maximum temperature distribution.
―305―
-305-
2000.0
sfem
Existing method
800.0
A’
A
1200.0
y
800.0
z
x
Boundary ΓGL between
global and local mesh
400.0
B
Temperature (rC)
Temperature (rC)
1600.0
0.0
1000.0
Developedfem
method
A
600.0
10.0
20.0
30.0
40.0
0.0
50.0
-0.02
F
-0.03
-0.04
y
-0.05
z
x
E
E
F
-0.06
-0.07
0.0
20.0
40.0
60.0
80.0
20.0
30.0
40.0
50.0
Fig. 10 Comparison of temperature history.㻌
0.45
H
Angular distortion SA (mm)
Transverse shrinkage ST (mm)
St method
- sfem
Existing
10.0
Time (s)
Developed
method
St - fem
ST
Existing
method
x
0.0
Fig. 9 Comparison of maximum temperature distribution.
-0.01
D
C
200.0
Coordinate in y-direction (mm)
0.00
z
D
B
400.0
A’
0.0
y
C
Developed
method
100.0
0.36
0.27
y
z
H
B’
G
x
0.18
Developed
Sa - method
fem
Samethod
- sfem
Existing
0.09
0.00
Coordinate in x-direction (mm)
G
B
0.0
10.0
20.0
30.0
40.0
50.0
Coordinate in y-direction (mm)
Fig. 12 Comparison of angular distortion distribution.㻌
Fig. 11 Comparison of transverse shrinkage distribution.
(MPa)
400.0
345.0
290.0
235.0
180.0
125.0
70.0
15.0
y
-40.0
-95.0
-150.0
z
x
(a) Existing method.㻌
(b) Developed method.㻌
Fig. 13 Distribution of residual stress in x direction (σx).㻌
600.0
A’
A
A
400.0
Stress (MPa)
ྥࡢኚ఩ศᕸࢆ♧ࡍ㸬ྠᅗࡼࡾ㸪㠃እ᪉ྥࡢኚ఩࡟
㛵ࡋ࡚ࡶ㸪㛤Ⓨᡭἲࡣᚑ᮶ᡭἲ࡜࡯ࡰྠ➼ࡢ⢭ᗘ࡛
ゎᯒྍ⬟࡛࠶ࡿࡇ࡜ࡀศ࠿ࡿ㸬
Fig. 13 ࡟ x ᪉ྥࡢṧ␃ᛂຊศᕸࢆ♧ࡍ㸬ࡲࡓ㸪Fig.
14 ࡟ A-A’⥺ୖࡢṧ␃ᛂຊศᕸࡢẚ㍑ࢆ♧ࡍ㸬ࡇࢀ
ࡽࡢᅗࡼࡾ㸪㛤Ⓨᡭἲ࡜㟼ⓗ㝜ゎἲ FEM ࡢゎᯒ⤖
ᯝ࡜༑ศ࡟୍⮴ࡋ࡚࠸ࡿࡇ࡜ࡀศ࠿ࡿ㸬≉࡟㸪࣮ࣟ
࣓࢝ࣝࢵࢩࣗ࡜ࢢ࣮ࣟࣂ࣓ࣝࢵࢩࣗࡢቃ⏺㒊࡟࠾
࠸࡚ࡶ୙㐃⥆ࢆ⏕ࡌࡿࡇ࡜࡞ࡃゎᯒ࡛ࡁ࡚࠸ࡿ㸬
௨ୖࡢ⤖ᯝࡼࡾ㸪ᇶ♏⥅ᡭၥ㢟࡟࠾࠸࡚㸪⇕ఏᑟ
ゎᯒ㸪⇕ᙎረᛶゎᯒ࡜ࡶ࡟㛤Ⓨᡭἲࡣ㸪ᚑ᮶ᡭἲ࡛
࠶ࡿ㝜ゎἲ FEM ࡜࡯ࡰྠ➼ࡢゎᯒ⢭ᗘ࡛࠶ࡿࡇ࡜
ࡀ☜ㄆ࡛ࡁࡓ㸬
y
z
Developed
method
Existing
method
σx
x
Boundary ΓGL between
global and local mesh
200.0
σy
A’
0.0
-200.0
0.0
10.0
20.0
30.0
Coordinate in y-direction (mm)
40.0
Fig. 14 Comparison of residual stress distribution.
―306―
-306-
50.0
㸲㸬」㞧ࣔࢹࣝࡢゎᯒ࡬ࡢ㐺⏝
㸲㸬㸯 ゎᯒࣔࢹࣝ࠾ࡼࡧ᮲௳
ᮏ❶࡛ࡣ㸪㛤Ⓨᡭἲࡢ」㞧ࣔࢹࣝ࡟࠾ࡅࡿ㐺⏝ᛶ㸪୪ࡧ࡟᭷ຠᛶࢆ☜ㄆࡍࡿࡓࡵ࡟㸪Fig. 15 ࡟♧ࡍࣔࢹࣝࡢ
ゎᯒ࡟ᑐࡋ࡚㛤Ⓨᡭἲࢆ㐺⏝ࡍࡿ㸬ྠᅗ࡟♧ࡍ㏻ࡾ㸪ᮏゎᯒ࡛ࡣ㸪እᚄ 200 mm㸪ෆᚄ 160 mm㸪㧗ࡉ 500 mm
ࡢࣃ࢖ࣉ࡜㸪ᖜ㸪㛗ࡉ 1000 mm㸪ཌࡉ 50 mm ࡢ㗰ᯈࡢ⁐᥋ࢆࣔࢹࣝ໬ࡋ࡚࠸ࡿ㸬ࢢ࣮ࣟࣂ࣓ࣝࢵࢩࣗࡢせ⣲ᩘ㸪
⠇Ⅼᩘࡣࡑࢀࡒࢀ㸪1,440㸪2,379 ࡛࠶ࡾ㸪࣮࣓ࣟ࢝ࣝࢵࢩࣗࡢせ⣲ᩘ㸪⠇Ⅼᩘࡣࡑࢀࡒࢀ㸪47,872㸪41,984 ࡛࠶
ࡿ㸬ࡲࡓ㸪ᮏࣔࢹࣝ࡟࠾࠸࡚ࡣ㸪Fig. 15 (a)࡟♧ࡍࡼ࠺࡟㸪ࣃ࢖ࣉ࡜ᯈᮦࡣࢢ࣮ࣟࣂ࣓ࣝࢵࢩࣗ࡟࠾࠸࡚ಶู࡟
ࣔࢹࣝࢆసᡂࡋ࡚࠾ࡾ㸪ࣃ࢖ࣉ࡜ᯈᮦࢆ᥋ྜࡍࡿ⟠ᡤࢆ࣮࣓ࣟ࢝ࣝࢵࢩࣗ࡟࠾࠸࡚ࣔࢹࣝ໬ࡋ࡚࠸ࡿ㸬ࡇࢀ࡟
ࡼࡾ㸪ࢢ࣮ࣟࣂ࣓ࣝࢵࢩࣗ࡟࠾࠸࡚ࣔࢹࣝ໬ࡉࢀࡓྛ㒊ᮦ࡟ᑐࡋ࡚㸪࣮࣓ࣟ࢝ࣝࢵࢩࣗ࡟࠾࠸࡚ࣔࢹࣝ໬ࡉࢀ
ࡓ᥋ྜ㒊ࢆ㔜ࡡྜࢃࡏࡿࡇ࡜࡛㸪ࡑࢀࡒࢀࡢ㒊ᮦࢆ⤖ྜࡍࡿ㸬࡞࠾㸪ࢢ࣮ࣟࣂ࣓ࣝࢵࢩࣗࡢྛ㒊ᮦྠኈࡣ⠇Ⅼ
ࢆඹ᭷ࡋ࡚࠸࡞࠸ࡓࡵ㸪඲ࡃಶูࡢ㒊ᮦ࡜࡞ࡗ࡚࠸ࡿ㸬࣮࣓ࣟ࢝ࣝࢵࢩࣗ࡟࠾࠸࡚ࡣ㸪Fig. 15 (b)ࡢᩳ⥺㒊࡟♧
ࡍ㏻ࡾ㸪ᯈᮦ࡜࣮࣓ࣟ࢝ࣝࢵࢩࣗࡢቃ⏺㸪ࣃ࢖ࣉ࡜࣮࣓ࣟ࢝ࣝࢵࢩࣗࡢቃ⏺ࡢኚ఩ࢆᣊ᮰ࡋ㸪ࣃ࢖ࣉࡢෆ㠃࡟
┦ᙜࡍࡿ⠇Ⅼࡣኚ఩ࢆᣊ᮰ࡋ࡞࠸ࡇ࡜࡛㸪ᯈᮦ㸪ࣃ࢖ࣉ࡜࣮࣓ࣟ࢝ࣝࢵࢩࣗࡢኚ఩ࡢ㐃⥆ᛶࢆ☜ಖࡋ㸪ࣃ࢖ࣉ
࡟ࡼࡿᯈᮦࡢ㈏㏻ࢆ⾲⌧ࡍࡿ㸬ࣃ࢖ࣉ࡜ᯈᮦࡢᮦ㉁ࡣ㸪㌾㗰ᮦࢆ௬ᐃࡋ㸪Fig. 5 ࡢᮦᩱᐃᩘࢆ⏝࠸ࡓ㸬
Pipe
50 mm
Plate
500 mm
㸲㸬㸰 ゎᯒ⤖ᯝ
Fig. 16 ࡟㸪᏶඲෭༷ᚋࡢ x ᪉ྥࡢኚ఩ศᕸࢆ♧ࡍ㸬Fig. 16 ࡼࡾ㸪⁐᥋⥺ᆶ┤᪉ྥ࡟཰⦰ࡢኚᙧࡀศᕸࡋ࡚࠸
ࡿࡇ࡜ࡀ☜ㄆ࡛ࡁࡿ㸬ࡲࡓ㸪ᮏゎᯒࣔࢹࣝࡣ㸪ᯈᮦࡢࢢ࣮ࣟࣂ࣓ࣝࢵࢩࣗ࡜࣮࣓ࣟ࢝ࣝࢵࢩࣗࡢቃ⏺㒊࡟࠾࠸
࡚㸪࣓ࢵࢩࣗศ๭ࡀ᏶඲࡟୍⮴ࡋ࡚࠸࡞࠸ࡀ㸪ቃ⏺㒊࡟࠾࠸࡚㸪㐃⥆ⓗ࡞ኚ఩ศᕸ࡜࡞ࡗ࡚࠸ࡿࡇ࡜ࡀศ࠿ࡿ㸬
ࡇࢀࡣ㸪࣮࣓ࣟ࢝ࣝࢵࢩࣗࡢቃ⏺᮲௳࡜ࡋ࡚㸪ࢢ࣮ࣟࣂ࣓ࣝࢵࢩࣗ࡜ࡢቃ⏺㒊࡟᏶඲ᣊ᮰ࢆ୚࠼ࡓࡇ࡜࡟ࡼࡿ㸬
ྠᵝ࡟㸪Fig. 17 ࡟᏶඲෭༷ᚋࡢ z ᪉ྥࡢኚ఩ศᕸࢆ♧ࡍ㸬z ᪉ྥࡢኚ఩ศᕸ࡟㛵ࡋ࡚ࡣ㸪ゅኚᙧ࡟ࡼࡾ㸪୰ኸ
㒊࡟ᑐࡋ࡚࿘㎶㒊ࡀᣢࡕୖࡀࡿࡼ࠺࡞ኚᙧ࡜࡞ࡗ࡚࠸ࡿࡇ࡜ࡀศ࠿ࡿ㸬ࡲࡓ㸪z ᪉ྥ࡟㛵ࡋ࡚ࡶ㸪ࢢ࣮ࣟࣂࣝ
࣓ࢵࢩࣗ࡜࣮࣓ࣟ࢝ࣝࢵࢩࣗࡢቃ⏺࡛㐃⥆ࡋࡓኚ఩ศᕸ࡜࡞ࡗ࡚࠸ࡿ㸬
௨ୖ♧ࡋࡓࡼ࠺࡟㸪⁐᥋⤌❧ࡢࡼ࠺࡞」㞧࡞ࣔࢹࣝࡢゎᯒ࡟࠾࠸࡚㸪㔜ྜ࣓ࢵࢩࣗἲࢆ⏝࠸ࡿࡇ࡜࡛㸪㒊ᮦ
ࡈ࡜࡟సᡂࡋࡓࣔࢹࣝ࡟ᑐࡋ࡚㸪⁐᥋㒊ࡢヲ⣽࡞ࣔࢹࣝࢆ㔜ࡡྜࢃࡏࡿࡇ࡜࡛ゎᯒࣔࢹࣝࢆᵓ⠏ࡍࡿࡇ࡜ࡀྍ
⬟࡛࠶ࡾ㸪ゎᯒࣔࢹࣝࡢసᡂࢆ኱ᖜ࡟⡆␎໬࡛ࡁࡿྍ⬟ᛶࡀ࠶ࡿࡇ࡜ࡀศ࠿ࡗࡓ㸬
Global mesh
Welding
torch
Local mesh
Inner
surface
of pipe
(a) Whole model.㻌
Boundary
between
global and
local mesh
(b) Zoomed view of welding part.㻌
Fig. 15 Welding assembly analysis model.㻌
(mm)
0.10
(mm)
0.50
0.08
0.43
0.06
0.37
0.04
0.31
0.02
0.24
0.00
0.18
-0.02
0.11
-0.04
0.05
-0.06
-0.08
-0.10
y
z
-0.02
-0.09
x
-0.15
Fig. 16 Distribution of displacement in x-direction.㻌
―307―
-307-
y
z
x
Fig. 17 Distribution of displacement in z-direction.㻌
㸳㸬⤖ゝ
ᮏ◊✲࡛ࡣ㸪⁐᥋ຊᏛゎᯒ࡟࠾ࡅࡿゎᯒᡭἲࡢ㧗ᗘ໬ࢆ┠ⓗ࡟㸪㔜ྜ࣓ࢵࢩࣗἲࢆ⏝࠸࡚⇕ᙎረᛶゎᯒ㸪⇕
ఏᑟゎᯒࡢᐃᘧ໬ࢆ⾜ࡗࡓ㸬㔜ྜ࣓ࢵࢩࣗἲࢆ⏝࠸ࡓ⁐᥋ຊᏛゎᯒᡭἲࡢᵓ⠏࡟ᙜࡓࡾ㸪㔜ྜ࣓ࢵࢩࣗἲࡢ≉
ᛶ࠿ࡽ㸪ィ⟬᫬㛫㸪࣓ࣔࣜᾘ㈝㔞ࡀ⭾኱࡟࡞ࡿྍ⬟ᛶࡀ࠶ࡿࡓࡵ㸪ⴭ⪅ࡽࡀ㛤Ⓨࢆ㐍ࡵ࡚࠸ࡿ⌮᝿໬㝧ゎἲ FEM
࡟ᇶ࡙ࡃᡭἲࢆᑟධࡋࡓ㸬㛤Ⓨᡭἲࡢᛶ㉁࡟ࡘ࠸࡚☜ㄆࡍࡿࡓࡵ࡟㸪ᇶ♏ⓗ࡞ࣅ࣮ࢻ࢜ࣥࣉ࣮ࣞࢺ⁐᥋ၥ㢟ࡢ
ゎᯒ࡟ᑐࡋ࡚㛤Ⓨᡭἲࢆ㐺⏝ࡋ㸪ᚑ᮶ᡭἲ࡟ࡼࡿゎ࡜ࡢẚ㍑ࢆ⾜ࡗࡓ㸬ࡲࡓ㸪㛤Ⓨᡭἲࡢ᭷⏝ᛶࢆ♧ࡍࡓࡵ࡟㸪
ཌᯈ࡜ࣃ࢖ࣉࢆ⁐᥋࡟ࡼࡾ⤌❧࡚ࡿၥ㢟ࡢゎᯒ࡟ᑐࡋ࡚㛤Ⓨᡭἲࢆ㐺⏝ࡋࡓ⤖ᯝ㸪௨ୗࡢ▱ぢࡀᚓࡽࢀࡓ㸬
1) 㛤Ⓨᡭἲࢆࣅ࣮ࢻ࢜ࣥࣉ࣮ࣞࢺ⁐᥋ၥ㢟ࡢ⇕ఏᑟゎᯒ࡟ᑐࡋ࡚㐺⏝ࡋ㸪㝜ゎἲ FEM ࡜ࡢẚ㍑ࢆ⾜ࡗࡓ㸬
ࡑࡢ⤖ᯝ㸪㛤Ⓨᡭἲࡣ ᗘᒚṔ㸪 ᗘศᕸඹ࡟㝜ゎἲ FEM ࡜࡯ࡰྠ➼ࡢゎᯒ⢭ᗘ࡛࠶ࡿࡇ࡜ࢆ☜ㄆࡋࡓ㸬
ࡲࡓ㸪
ࢢ࣮ࣟࣂࣝ࡜࣮࣓ࣟ࢝ࣝࢵࢩࣗࡢቃ⏺㒊࡟࠾࠸࡚ࡶ ᗘศᕸࡀ㐃⥆ⓗ࡜࡞ࡗ࡚࠸ࡿࡇ࡜ࢆ☜ㄆࡋࡓ㸬
2) ࣅ࣮ࢻ࢜ࣥࣉ࣮ࣞࢺ⁐᥋ၥ㢟ࡢ⇕ᙎረᛶゎᯒ࡟ᑐࡋ࡚㛤Ⓨᡭἲࢆ㐺⏝ࡋ㸪㟼ⓗ㝜ゎἲ FEM ࡢゎᯒ⤖ᯝ࡜
ࡢẚ㍑ࢆ⾜ࡗࡓ㸬ࡑࡢ⤖ᯝ㸪㛤Ⓨᡭἲࡣኚ఩ศᕸ㸪ᛂຊศᕸඹ࡟㟼ⓗ㝜ゎἲ FEM ࡜࡯ࡰྠ➼ࡢゎᯒ⢭ᗘ
࡛࠶ࡿࡇ࡜ࢆ☜ㄆࡋࡓ㸬ࡲࡓ㸪ࢢ࣮ࣟࣂ࣓ࣝࢵࢩࣗ࡜࣮࣓ࣟ࢝ࣝࢵࢩࣗࡢቃ⏺㒊࡟࠾࠸࡚ࡶ㸪ኚ఩㸪ᛂຊ
ඹ࡟㐃⥆ⓗ࡞ศᕸࡀᚓࡽࢀ࡚࠸ࡿࡇ࡜ࢆ☜ㄆࡋࡓ㸬
3) ࣃ࢖ࣉ࡜ཌᯈࢆ⁐᥋࡟ࡼࡾ⤌❧࡚ࡿၥ㢟࡟࠾࠸࡚㸪ࣃ࢖ࣉ࡜ཌᯈࢆಶู࡟ࣔࢹࣝ໬ࡋ㸪⁐᥋㒊ࢆ⾲ࡍ࣮ࣟ
࣓࢝ࣝࢵࢩࣗ࡟ࡼࡾࡑࢀࡒࢀࡢ㒊ᮦࢆ⤖ྜࡉࡏࡓゎᯒࣔࢹࣝࢆ⏝࠸࡚㸪㛤Ⓨᡭἲ࡟ࡼࡾゎᯒࢆᐇ᪋ࡋࡓ㸬
ࡑࡢ⤖ᯝ㸪㛤Ⓨᡭἲࡣ」ᩘࡢ㒊ᮦࢆ࣮࣓ࣟ࢝ࣝࢵࢩࣗ࡟ࡼࡾ⤖ྜࡍࡿࡼ࠺࡞ၥ㢟࡟࠾࠸࡚ࡶ⁐᥋ຊᏛゎᯒ
ࢆ⾜࠺ࡇ࡜ࡀ࡛ࡁ㸪㛤Ⓨᡭἲࡣ」㞧ᵓ㐀≀ࡢࣔࢹࣝ໬࡟ᑐࡋ࡚ຠᯝⓗ࡛࠶ࡿࡇ࡜ࢆ♧ࡋࡓ㸬
ཧ⪃ᩥ⊩
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