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This is an Open Access document downloaded from ORCA, Cardiff University's institutional repository: http://orca.cf.ac.uk/102950/ This is the author’s version of a work that was submitted to / accepted for publication. Citation for final published version: Peng, Xuan, Atroshchenko, E., Kerfriden, Pierre and Bordas, Stephane Pierre Alain 2017. Isogeometric boundary element methods for three dimensional static fracture and fatigue crack growth. Computer Methods in Applied Mechanics and Engineering 316 , pp. 151-185. 10.1016/j.cma.2016.05.038 file Publishers page: http://dx.doi.org/10.1016/j.cma.2016.05.038 <http://dx.doi.org/10.1016/j.cma.2016.05.038> Please note: Changes made as a result of publishing processes such as copy-editing, formatting and page numbers may not be reflected in this version. For the definitive version of this publication, please refer to the published source. You are advised to consult the publisher’s version if you wish to cite this paper. This version is being made available in accordance with publisher policies. See http://orca.cf.ac.uk/policies.html for usage policies. Copyright and moral rights for publications made available in ORCA are retained by the copyright holders.

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Page 1: Isogeometric boundary element methods for three dimensionalorca.cf.ac.uk/102950/1/102950 - Isogeometric boundary... · 2021. 1. 20. · Isogeometric boundary element methods for three

This is an Open Access document downloaded from ORCA, Cardiff University's institutional

repository: http://orca.cf.ac.uk/102950/

This is the author’s version of a work that was submitted to / accepted for publication.

Citation for final published version:

Peng, Xuan, Atroshchenko, E., Kerfriden, Pierre and Bordas, Stephane Pierre Alain 2017.

Isogeometric boundary element methods for three dimensional static fracture and fatigue crack

growth. Computer Methods in Applied Mechanics and Engineering 316 , pp. 151-185.

10.1016/j.cma.2016.05.038 file

Publishers page: http://dx.doi.org/10.1016/j.cma.2016.05.038

<http://dx.doi.org/10.1016/j.cma.2016.05.038>

Please note:

Changes made as a result of publishing processes such as copy-editing, formatting and page

numbers may not be reflected in this version. For the definitive version of this publication, please

refer to the published source. You are advised to consult the publisher’s version if you wish to cite

this paper.

This version is being made available in accordance with publisher policies. See

http://orca.cf.ac.uk/policies.html for usage policies. Copyright and moral rights for publications

made available in ORCA are retained by the copyright holders.

Page 2: Isogeometric boundary element methods for three dimensionalorca.cf.ac.uk/102950/1/102950 - Isogeometric boundary... · 2021. 1. 20. · Isogeometric boundary element methods for three

s♦♦♠tr ♦♥r② ♠♥t ♠t♦s ♦r tr ♠♥s♦♥

t r r♦t

❳ P♥1 tr♦s♥♦2 P rr♥1 P ♦rs3,1,4¶

1♥sttt ♦ ♥s trs ♥ ♥ ♥tr♥ r ❯♥rst②

2♣rt♠♥t ♦ ♥ ♥♥r♥ ❯♥rst② ♦ ♥t♦

3❯♥rsté ①♠♦r té s ♥s ♥♦♦ t ♦♠♠♥t♦♥

r r ♦♥♦r ①♠♦r sr ❯♥t ♥ ♥♥r♥

♥ ♠♣s rr

4♦♥♦rr② Pr♦ss♦r ♥t♥t ②st♠s ♦r ♥ ♦rt♦r② ♦♦ ♦ ♥ ♥

♠ ♥♥r♥ ❯♥rst② ♦ ❲str♥ str tr♥ ②

r② ❲ str

s♦♦♠tr ♦♥r② ♠♥t ♠t♦ s ♦♥ ❯ s ♦♣t t♦ ♠♦

rtr ♣r♦♠ ♥ ❯ ss ♥t♦♥s r s ♥ ♦t r r♣rs♥tt♦♥

♥ ♣②s q♥tt② ♣♣r♦①♠t♦♥ st qrtr s♠ ♦r s♥r ♥trt♦♥ s

♣r♦♣♦s t♦ ♥♥ t r♦st♥ss ♦ t ♠t♦ ♥ ♥ t ② st♦rt ♠♥t

♦♥r♥ st② ♥ r ♦♣♥♥ s♣♠♥t s ♣r♦r♠ ♦r ♣♥♥②s♣ r ♥

♣t r ♦ ②s t♦ ①trt strss ♥t♥st② t♦rs s t ♦♥t♦r M ♥tr

♥ rt r ♦sr ♥tr r ♠♣♠♥t s ♦♥ t r♠♦r ♦ ♥tr

qt♦♥s ♥ ♦rt♠ s ♦t♥ ♥ t t♦ st ♦r t r r♦t t♥s

t♦ t s♠♦♦t♥ss ♥♦t ♦♥② ♥ r ♦♠tr② t s♦ ♥ strsss s♦t♦♥ r♦t ②

②❲♦rs s♦♦♠tr ♥②ss ❯ ♥r st rtr ♦♥r② ♠♥t ♠t♦

r r♦t

¶♦rrs♣♦♥♥ t♦r ①♠ rssst♣♥♦rs♠♥♦rtstr♥

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♥tr♦t♦♥

s♠t♦♥ ♦ t t rtr ♣r♦♣t♦♥ s ♥♦t ♦♥② r t♦ ♣r♦r♠ t ♠

t♦r♥ ssss♠♥t ♦r ♣rt t sr♥ ♦ ♠♥ ♦♠♣♦♥♥t t s♦ t♦ ♣ t

♥rst♥ ♦ t ♠♥s♠ ♦ strtrs r ♥ ♥♥r♥ ❱rst ♥♠r ♠t♦s

♥ tt♠♣t ♦r ♠♦♥ t rtr t t ♦♣♠♥t ♦ ♦♠♣tt♦♥

♠♥s ♥ ♣st s ♥s ♦r ♥♠r rtr ♠♦♥ ♣r♠r② ♥ t

♠s♥r♠s♥ ♣r♦r s t ♥tt♦♥ ♦ t rs r s② t♦ ♦r ♠♦r ♦rrs

s♠r ♥ ♦♠tr② s③ t♥ t ♦♠♣♦♥♥ts r♥t s ♦ t rs ♥ ♦♠♣♦♥♥ts

rqrs ♦ r♥ ♠s ♦r t ♥t♦♥ ♦ t ts ♥ r♠s♥ ♦♠ ♥ssr②

♦r rt s♠t♦♥ ♥ t rs ♣r♦♣t

♥t ♠♥t ♠t♦ ♥ ♣♣ t♦ s♠t t r ♣r♦♣t♦♥ rt② t

rt♥ ♣t r♠s♥ ♦♣rt♦♥ ❬❪❬❪❬❪ ♦♠ s♦tr ♣s ♥ ♦♣

s ♦♥ ts ❬❪❬❪ ♥ r ♣♣r ♥ rrr ❬❪ rtss t r♠s♥

♦♠s ♠rs♦♠ ♦r ♠trs ♦r ♦r r② ♦♠♣t ♦♠♣♦♥♥ts s t ♦♠♣①t② s

♥rs t♦ t ♣rs♥ ♦ rs s ♥tr♥ ♦♥rs

♦ ♣rtt♦♥ ♦ ♥t② P❯ ♥r♠♥t s ♥ ♣r♦♣♦s t♦ rs t ♠s r♥

♥ rtr ♠♦♥ ❬❪ t♦ t t♦♥ ♥r♠♥t ♥t♦♥s t s♦♥t♥ts r

♥tr♦ ♥t♦ t ♠♦ ♥ t r♣rs♥tt♦♥ ♦ t r ♦♥② ♠s ♦r ♥tt♥ t ♥

r♠♥ts ♠s t r ♠s ♥♣♥♥t r♦♠ t ♦♠♣♦♥♥ts ♠s ①t♥

♥t ♠♥t ♠t♦ ❳ ❬❪ s② ♦♣ t t st ♥t♦♥s s ♥ ♠♣t

r♣rs♥tt♦♥ ♦ t r s ♥ ♠♣♠♥t ♦r r r♦t ♣r♦♠ ❬❪❬❪❬❪❬❪

s s ♦r ♥str ♣♣t♦♥s ❬❪❬❪❬❪ ♠sr ♠t♦s s♦ ♥ ♣r♦

♣♦s t t ♠ ♦ rtr r♥ t ♠s r♥ ♦r ♥st♥ t ♠♥tr r♥

❬❪ ♥ t ①t♥ ❳ ❬❪❬❪❬❪ ♦r ♠♦r ts t rrs ♦

rr t r ♣♣r ② ②♥ t ❬❪

rtr ♠♦♥ ② t ♦♥r② ♠♥t ♠t♦ ①ts ♠♦r ♥ts t♥

② ♥ tr♠s ♦ ♠sr♠s ♦rts s ♦♥② t ♦♥r② srt③t♦♥ s rqr ♥

♥ ♦rr t♦ ♣♣r♦①♠t t q♥tt② ♦ ♥trst ❲♥ rs ♦ ♦♥② t ♦♥r②

srs r ♣t ♥st ♦ r♥rt♥ t ♦♠ ♠s ♥ ♦rr t♦ r♠♥t t

s♥r s②st♠ s ② t ♦♣s srs ♥ rtr ♦♥ ♥ ♥ ❬❪ ♣r♦♣♦s

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t ♦♥r② ♥tr r♣rs♥tt♦♥s ② ♥tr♦♥ t ②♣rs♥r qt♦♥ r

r♦♠ t s♦♥r② ❬❪ s ♦ ♦♥r② ♥tr qt♦♥ ♠s t r

♣r♦♣t♦♥ s♠t♦♥ ♠♦r t tr♦ s♥ ♦♠♥ ♥ t ♦rrs♣♦♥♥

s ssq♥t② ♠♣♠♥t ♦r ♥ rtr ❬❪❬❪❬❪ ♥ s ①t♥ t♦

♠tr♥♦♥♥r rtr ❬❪❬❪ ♥ ②♥♠ r ♣r♦♣t♦♥ ❬❪ ♦♠♠r ♣s

s ♦♥ r ❨ ❬❪ ♥ ❬❪ ♣rt r♦♠ t s ♦♥ t

♦♦t♦♥ ♠t♦ t r♥ ♥ ♣rtr t s②♠♠tr r♥

s s♦ r♥ tt♥t♦♥ ♥ t ♣♣t♦♥ ♦r rtr ♥②ss ❬❪❬❪❬❪ s②♠♠tr

♠tr① s②st♠ ♦ s♦ tts t ♦♣♥ t ❬❪❬❪

s♦♦♠tr ♥②ss s rst ♥tr♦ ② s t ❬❪ s ♦

s t♦ s t s♠ s♣♥ ss ♥t♦♥s t♦ r♣rs♥t t ♦♠trs ♥ ♣♣r♦①

♠t t ♣②s q♥tts ♦ ♥trst ♥ t ♥stt♦♥ ♦♥ t ♦♥t ♦ ♥

s ♥rs♥② r♥ tt♥t♦♥ r♥t② s♥ ♦♥② t ♦♥r② r♣rs♥tt♦♥ ♦

t ♦♠tr② s rqr ♥ tts t ♥trt♦♥ ♦ s♥ ♥ ♥②ss

s r② ♥ ♣♣ ♥ ♠♥② s ❬❪❬❪❬❪❬❪❬❪❬❪❬❪❬❪ ♥ s

♥ rtr ♦♣ t ♠♦r ♥♠r s♣ts s s t P❯ ♥r♠♥t ❬❪❬❪ t

tr♠♠ ❯ ❬❪❬❪ t st s♦t♦♥ ❬❪ t r♥ ♦r♠ ❬❪❬❪ t ♥t ♦

s♠♦♦t♥ss t♦ ♦♥r② ♥trs s r♦t ② s ♥stt ♥ ❬❪

s♦♦♠tr ♥②ss s ♥ ♣♣ t♦ rtr ♥ ♦r♣♦rt♦♥ t ❳ ❬❪❬❪❬❪❬❪

❱r♦♦s t ♣rs♥t s♠ t♦ ♠♦ ♦s r ♣r♦♣t♦♥ ② s♥ s♣♥s t♦

♥rt t ♦ s♦♥t♥ts ❬❪ ②♥ t ♣♣ t s♣♥ s t♦ s♠t

t ♥ ♠♥t♦♥ ♥ ♦♠♣♦sts ❬❪ s♣ s♥stt② ♥②ss ♦ strss ♥t♥

st② t♦rs ♦r r rs s ♣r♦r♠ ② ♦ ♥ ♦ ❬❪ ♠t t ♣r♦♣♦s ♥

♥r s ♦♥ t ♥s♣r r ♣rtt♦♥ ♦ ♥t② ♦♠♣♦st♦♥s

♥ t ♠t♦ ♥ts r♦♠ r♦st ♥ ♥♦♥trt ♥♠r st♥ ♦♥strt♦♥

❬❪❬❪ ♦♥ t ♣r♦♣♦s ♦♠tr ♠♣♣♥ ② ♣s♦rrs ♦ s♣♥s r♦♠

t ♣r♠tr s♣ ♥t♦ t ♣②s s♣ s tt t s♥rt② ♦ t②♣ r1/2 ♥ ♣

tr ♥ ♥r st rs ❬❪❬❪ tr♥ t ♥♥ t s♦♦♠tr ♥②ss ②

t s ♦♥r② ♥t ♠♥t ♠t♦ ♥rts ♦t ♥ts ♦ ♥

rt♥ ss♦♥ ♦ t ♦♠♥ ♥s t♦ ♦♥ ♦r ♦♠♣t ♦♠tr② ♥

♦rr t♦ ♦t♥ t s♥ ♥tr ❬❪ ♣♦t t♣s ♦ t ♣♣t♦♥ ♥ rtr ♥ t

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r♠♦r ♥ ♦♥ s

r♦rr ♦♥t♥t② ♠♣r♦s t r② ♦ t strss ♥r t r t♣

s r t♦ rtr ♥②ss ♥ t rs ♦ r♦♠ s r ♦♠♣r t♦ t C0

r♥ ss

rtr t♥♥t ♥ ♥♦r♠ t♦rs r ①t② rt♥ ♥ ♦ t♥s t♦

t ①t r♣rs♥tt♦♥ ♦ t r rs

♦ r t♣ r♦♥t s②st♠ ♥ ♦♥strt rt② s ♦♥ t s♣♥s

r ♦r srr♣rs♥t rs ♣s t♦ rt② t t rtr ♣r♠trs

♦♥♣t ♦ ♥trt♦♥ tr♦ s♥ t♦ ♥②ss ts t ♠♥strtr

s♥ s ♦♥ t t rtr ♥②ss

♥ ts ♦r t ♣♣t♦♥ ♦ ♥ rtr ♥②ss ♥ t r r♦t

①♣♦r ss s♥ t ♦♥♥t♦♥ ♦♥r② ♥tr qt♦♥ s ♦r stt②

t ②♣rs♥r ♥tr qt♦♥ s ♥tr♦ t♦♥② ② ①♣♦t♥ t s♠♦♦t♥ss

♦ ❯ ♦♠trs ♥ ♦ s♥rt② r♠♦♥ t♥q ♣r♦♣♦s ② ♥ ❬❪

s ♣♣ ♦♥ t r♦s ♦rrs ♦ s♥r ♥trs ♣ t♦ ②♣rs♥r O(1/r3) ♥ ts

♠♣r♦ rs♦♥ t♦r t♦ st♦rt ♠♥ts ♦r t s♣t rt♦ ♦♠♠♦♥② rs

♥ s♦♦♠tr s ♠t♦s s ♦r♠t r s ①♣t② r♣rs♥t ② ❯

sr s ♥tr♥ ♦♥r② ♥ ♥ ♦rt♠ s ♦t♥ t♦ sr t r ♣r♦♣t♦♥

s tt t s♠♦♦t♥ss ♥ ♦♠tr② r♦t ② ♥ ♥ s♦t♦♥ r♦t ② s ②

♥stt ♦r ①trt♥ t strss ♥t♥st② t♦rs ♥ r r♦t

rst ♦ t ♣♣r s ♦r♥③ s ♦♦s t♦♥ rs t ♦♥r② ♥tr qt♦♥s

s tt ♣♣ ♥ rtr ♠♦♥ t♦♥ strts t ❯ ss ♥t♦♥s ♦♥

srs ♥ t ♦♦t♦♥ s♠ t♦♥ ♦t♥s t ♠♣r♦ s♥r ♥trt♦♥

s ♦♥ t s♥rt② strt♦♥ t♥q ❬❪ r r♦t rt ♦r s t

♥ st♦♥ ♥♥ ♣t♥ t r sr ♦♠tr② ♦♠♣t♥ t strss ♥t♥st②

t♦rs ♥ t t rtr r t Prs ♠r ①♠♣s ♦r ♦t stt rtr

♥②ss ♥ r r♦t r ♥ ♥ st♦♥ ❲ ♦♥ ♦r ♦r ♥ ♣r♦♣♦s t tr

rsr ♦ ♥trst ♥ t st st♦♥

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♦♥r② ♥tr qt♦♥s ♦r r ♠♦♥

♦♥sr ♥ rtrr② ♦♠♥ Ω ♦♥t♥s r s ♥ r ♦♥r② ♦ t

♦♠♥ ∂Ω = S + Sc+ + Sc− r S s ♦♠♣♦s ♦ Su r rt ♦♥r② ♦♥t♦♥s

r ♣rsr ♥♦♥ s♣♠♥t u St r ♠♥♥ ♦♥r② ♦♥t♦♥s r ♣rsr

♥♦♥ trt♦♥ t s♣♠♥t s ♥ ② ♥♥ u ♥ t s tt

cij(s)uj(s) =

∂ΩUij(s,x)tj(x)S(x)−−

∂ΩTij(s,x)uj(x)S(x),

r t Uij Tij r ♥♠♥t s♦t♦♥s ♥ ♦r ♥r stt②

Uij(s,x) =1

16πµ(1− ν)r[(3− 4ν)δij + r,ir,j ] ,

Tij(s,x) = − 1

8π(1− ν)r2

∂r

∂n[(1− 2ν)δij + 3r,ir,j ]− (1− 2ν)(r,inj − r,jni)

,

r µ = E/[2(1 + ν)] E s ❨♦♥s ♦s ♥ ν P♦ss♦♥s rt♦ s s t s♦r ♣♦♥t ♦r

♦♦t♦♥ ♣♦♥t s t♦ tr♠s s ♥tr♥② ♥ t r♠♥r ♣rt ♦ ts

♣♣r −∫

♥♦ts t ♥tr s ♥tr♣rt ♥ t ② Pr♥♣ ❱ s♥s trt♦♥

s ♦t♥ ② r♥tt♦♥ ♦ t s♣♠♥t t rs♣t t♦ s ♥ ♠t♣t♦♥

② t st t♥s♦r Eijkl

cij(s)tj(s) = −∫

∂ΩKij(s,x)tj(x)S(x)−=

∂ΩHij(s,x)uj(x)S(x),

Hij(s,x) = Eikpq∂Tpj(s,x)

∂sqnk(s), Kij(s,x) = Eikpq

∂Upj(s,x)

∂sqnk(s),

r =∫

♥♦ts t ♠r ♥t Prt ♥tr

♦ t ♦♥r② ♠♥t ♠t♦ s t♦ srt③ t ♦♥r② ♦♠tr② ♥ t

♣②s s s♥ sts ♦ ss ♥t♦♥s sq♥t② t s♦r ♣♦♥t s ♣ t t

♦♦t♦♥ ♣♦♥ts ♥ t s♣♠♥t s tr♥s♦r♠ ♥t♦ t s②st♠ ♦ ♥r r

qt♦♥s ♦r ♥ t ♦♠♥ ♦♥t♥s r t ♦♦t♦♥ ♣♦♥ts ♦♥ t ♦r♣♣♥

srs Sc+ ♥ Sc− ♦ ♦♥ rr t♦ r ♥ t♥ t s②st♠ ♠tr①

♦♠s s♥r ♦ ②s t♦ t ts ♣r♦♠ r r ♥ t ♦♦♥ st♦♥s

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r r ♠♦

qt♦♥s

t② s ② t ♦♣s r srs s r♠♥t tr♦ t s ♦

qt♦♥s ② ♣rsr♥ t s♣♠♥t qt♦♥ ♦♥ ♦♥ r sr Sc+ ♥

♦♥ t rst ♦ t ♦♥r② S ♦r t ♦♦t♦♥ ♣♦♥t s+ ♦♥ t r sr Sc+ qt♦♥

♥ rrtt♥ s

cij(s+)uj(s

+) + cij(s−m)uj(s

+) =

SUij(s

+,x)tj(x)S(x)−∫

STij(s

+,x)uj(x)S(x)

−−∫

Sc+

Tij(s+,x+)uj(x

+)S(x)−−∫

Sc−

Tij(s−m,x

−)uj(x−)S(x)

+

Sc+

Uij(s+,x+)tj(x

+)S(x) +

Sc−

Uij(s−m,x

−)tj(x−)S(x).

♥ ♥♦♦s② t trt♦♥ qt♦♥ ♦♥ t ♦tr r sr Sc− ♥ r

♦♠s

cij(s−)tj(s

−) + cij(s+m)tj(s

−) =

SKij(s

−,x)tj(x)S(x)−∫

SHij(s

−,x)uj(x)S(x)

−=

Sc−

Hij(s−,x−)uj(x

−)S(x) + =

Sc+

Hij(s+m,x

+)uj(x+)S(x)

+−∫

Sc−

Kij(s−,x−)tj(x

−)S(x)−−∫

Sc+

Kij(s+m,x

−)tj(x+)S(x).

s−m ♥♦ts t ♠rr♦r ♣♦♥t ♦ s+ ♦♥ t Sc− ♠♥s s−m ♥ s

− sr t s♠ ♣②s

♥ ♣r♠tr ♦♦r♥t t t ♥♦r♠ t♦rs t r ♦♣♣♦st st t♦ tr♠s ♦

♦t qt♦♥s ♥ t ♥ s ♦ qt♦♥ r ♦♠tt t♦ t rt♦♥r r

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t♦ t ♦♣s ♦♥r② ♥ rtr ♣r♦♠ t♦ ♠♣ tr♠s rs ♥ ♥

♦♣rt♦r ♥♦t ♦♥② ①ts s♥rt② ♦♥ t r sr r t ♦♦t♦♥ ♣♦♥ts ♦t

t s♦ ♦♥ t ♦♥ r t ♠rr♦r ♣♦♥ts ♦ t ♦♦t♦♥ ♣♦♥ts ♦t

r ♦♣♥♥ s♣♠♥t qt♦♥

♦♥r② ♥tr qt♦♥ ♦r r ♣r♦♠ ♥ s♦ r♦r♠t ② stt♥ t

♦♥r② q♥tt② s r ♦♣♥♥ s♣♠♥t ♦r ♦♣ ♦ r srs t t s♦r

♣♦♥t ♣♣r♦ t♦ s♥ r sr ♦r ①♠♣ Sc = Sc+ ♥ ♥♦t tt n = n+ = −n

cij(s+)uj(s

+) + cij(s−)uj(s

−) =

SUij(s

+,x)tj(x)S(x)−−∫

STij(s

+,x)uj(x)S(x)

+

Sc

Uij(s+,x+)(tj(x

+) + tj(x−))S(x)

−−∫

Sc

Tij(s+,x+)(uj(x

+)− uj(x−))S(x).

♦rrs♣♦♥♥ trt♦♥ s

cij(s+)tj(s

+)− cij(s−)tj(s

−) = −∫

SKij(s

+,x)tj(x)S(x)−=

SHij(s

+,x)uj(x)S(x)

+−∫

Sc

Kij(s+,x+)(tj(x

+) + tj(x−))S(x)

−=

Sc

Hij(s+,x+)(uj(x

+)− uj(x−))S(x).

qt♦♥ ♥ s ♦♥ ♦♥② t ♣rs♥t s t ♥♥♦♥ ♦r t

rtr ♣r♦♠ ♦r t s♣♠♥t ♥s t♦ ♥♦♥ ♦♥ t r srs

qt♦♥ s♦ s♦ s♦ t S → ∞ ♥ ♥♦t tt trt♦♥r r srs r

ss♠ rr t

0 = t∞j (s)−=

Sc

Hij(s,x)Juj(x)KS(x).

Juj(x)K = uj(x+)−uj(x−) s t r ♦♣♥♥ s♣♠♥t t ssr♣ts ❵ r ♦♠tt

s♥ t ♥tr s ♦♥② ♦r s♥ r sr t∞ s ♥tr♣rt s t s♦t♦♥ ♥ t ❵♥♦

r s♣

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❯ srt③t♦♥ ♥ ♦♦t♦♥

❯ ss ♥t♦♥s r t ♥r③t♦♥ ♦ s♣♥ ♥t♦♥s tt ♦s ❵♣r♦t♦♥

r♦♠ sqr ♥ ♦♠♥s t♦ ♦r♠ ♦♠♣① ♦♠trs ♦ t s ♦♥♣t ♦ s♣♥ s

rst ♦t♥ s♣♥ ss ♥t♦♥s r ♥ ♦r ♥♦t t♦r s ♥♦♥rs♥

sq♥ ♦ r ♥♠rs ♥ ♥ t ♣r♠tr s♣ ♥♦t t♦r s ♥♦t s Ξ =

ξ1, ξ2, ..., ξn+p+1 r ξi ∈ R s t it ♣r♠tr ♦♦r♥t ♥♦t p s t ♦rr ♦ t

♣♦②♥♦♠ ♥ s♣♥ ss ♥t♦♥s n s t ♥♠r ♦ t ss ♥t♦♥s ♦r ♥ ♦rr

p t s♣♥ ss ♥t♦♥s Ni,p t 1 6 a 6 n r ♥ ② t ♦① ♦♦r rrs♦♥

Ni,0(ξ) =

1 ξi 6 ξ < ξi+1

0 ♦trs

t♥ ♦r p > 0

Ni,p(ξ) =ξ − ξiξi+p − ξi

Ni,p−1(ξ) +ξi+p+1 − ξ

ξi+p+1 − ξi+1Ni+1,p−1(ξ).

♦♥t♥t② ♦ s♣♥ ss ♥t♦♥s t ξi ♥ rs ② r♣t♥ t ♥♦t sr

t♠s ξi s ♠t♣t② k ξi = ξi+1 = ... = ξi+k−1 t♥ t ss ♥t♦♥s r Cp−k

♦♥t♥♦s t ξi Prtr② ♥ k = p t ss s C0 ♥ k = p+1 s t♦ s♦♥t♥t②

t ξi t rst ♥ st ♥♦t k = p + 1 t ♥♦t t♦r s ♥ ♦♣♥ ♥♦t t♦r

♦r ts ♥ rrr ♥ ❬❪

♥ t ♥♦t t♦rs Ξ = ξ1, ξ2, ..., ξn+p+1 ♥ H = η1, η2, ..., ηm+q+1 ♥ t ♦♥tr♦

♣♦♥ts ♥t Pi,j s♣♥ sr S(ξ, η) s ♥ ② t t♥s♦r♣r♦t ♦ s♣♥ ss

♥t♦♥s ♥ ♥ ♣r♠tr ♦♠♥ [ξ1, ξn+p+1]× [η1, ηm+q+1]

S(ξ, η) =n∑

i=1

m∑

j=1

Ni,p(ξ)Mj,q(η)Pi,j ,

r Ni,p(ξ)Mj,q(η) r t s♣♥ ss ♥t♦♥s ❯ ss ♥t♦♥s ♥

♦♥strt ② rt♦♥③♥ t t♥s♦r♣r♦t s♣♥ ss ♥t♦♥s s

Ri,j(ξ, η) =Ni,p(ξ)Mj,q(η)wi,j

∑nk=1

∑ml=1Nk,p(ξ)Ml,q(η)wk,l

,

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r t sr r wi,j s t t ss♦t t t ♦♥tr♦ ♣♦♥t Pi,j ♦r ♥trt♦♥

♣r♣♦s t ❯ ss ♥t♦♥s r s② t ♥ t ♠♥t ♥ ② t

♥♦♥③r♦ ♥♦t ♥trs [ξi, ξi+1]× [ηj , ηj+1] r t ss♥ r ♥ ♣♣ ❬❪

r sss s ♥ s t♦ ♥rt t ♦♦t♦♥ ♣♦♥ts ♦r ♦s ♦♠♥

♦♠♣♦s ② tr♠ss ♥ ♦♠♣t ❯ ♣ts t ♥♠r ♦ ♦t♥ ♦♦t♦♥

♣♦♥ts ② t r sss s ♥t t♦ t ♥♠r ♦ ♦♥tr♦ ♣♦♥ts ♦r ss ♥t♦♥s

♠♥s ♦♥ ♦♦t♦♥ ♣♦♥t s ss♦t t ♦♥ ♦♥tr♦ ♣♦♥t ♦r t♦s ♦♦t♦♥

♣♦♥ts ♥ t sr♣ s ♦r ♦r♥rs ♦r ♥ s♦♥t♥♦s ss ♥t♦♥s r ♥ ts

♦♦t♦♥ ♣♦♥ts ♦st r♦♠ t ♦r♥ ♣ ②

ξs,i = ξs,i + α(ξs,i+1 − ξs,i), ♦r

ξs,i = ξs,i − α(ξs,i − ξs,i−1), α ∈ (0, 1).

♦t tt ♥ ts s t ss♦t ♦♥tr♦ ♣♦♥ts s♦ ♦ s tt t s♦♥t♥

♦s ss ♥t♦♥s r ♦t♥ ♦r t s ♦♥ t ♦st ♦♦t♦♥ ♣♦♥ts s♦ ♠r

♥t♦ ♦♥ s tt t ♥♠r ♦ qt♦♥s ♥ ♥♥♦♥s ♣s ♦♥sst♥

♠r ♥trt♦♥

t♦ t s♥rts ♥ s tr s♥r ♥trt♦♥ ♥ ♥♦♥s♥r ♥trt♦♥

tr srt③t♦♥ ♦r t ♠♥t ♦♥t♥♥ t ♦♦t♦♥ ♣♦♥t s♥r ♥trt♦♥ s

♣r♦r♠ ♥ t ♠♥t ♦♥s t♦ s♥r ♠♥ts ♠♥ts ① t ♦♦t♦♥

♣♦♥t r ♥♦♥s♥r ♠♥ts s♥r ♥trt♦♥ ♥s t♦ r② trt ♥

❱r♦s ♥♠r ♠t♦s ♥ ♣r♦♣♦s ♥ ♣st s ♥ ♦♥ ♥ rr t♦

r ♦r ♥ ❬❪ r♦st t♥q ♦♣ ♥ ❬❪ ♥ ♣♣ t♦ rr③ t

s♥r tr♠s ♥t♦ ② s♥r t s ♦ s♠♣ s♦t♦♥ ♦ rr③t♦♥

t♥q s ♦♥ s♠♣ s♦t♦♥s s ♥ ♣♣ ♦r rtr ♦♣ ♥ t r♠♦r

♦ ❬❪❬❪❬❪ ♦r ts ♠t♦ s ♥ ♥ t ♦♣♥ srs s s

rs ❬❪ ♥ t ♣rs♥t ♦r s t s♥rt② strt♦♥ t♥q ♣r♦♣♦s

② ♥ ❬❪❬❪ t♦ r♠♦ t s♥rts rs ♥ ♦t s s ♥t ♠t♦

♦r t trt♠♥t ♦ s♥r ♥trs rrss ♦ ♠s rt③t♦♥ ♥ ♣r♦ t♦ ♥t

♦r rtr ❬❪

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♥rt② strt♦♥ t♥q ♦r s♥r ♥trs

tr♥s♦r♠s r♦s ♦rrs ♦ s♥r ♥trt♦♥ ♥t♦ ② s♥r ♦♥ s ♦♥

t ♥tr♥s ♦♦r♥t s②st♠ ♦ t s♥r ♠♥t tr srt③t♦♥ ♥ t ②

s♥r ♥trt♦♥ tr♥s t♦ rr t qrtr s ♣r♦r♠ ♥ t ♣♦r ♦♦r♥ts

② ①♣♥♥ t ♥tr♥ ♥t♦ srs t rs♣t t♦ t ♥tr♥s ♦♦r♥t t s♥rt②

♥ r♣rs♥t ①♣t② ♥ t s♥r tr♠s r strt r♦♠ t ♥tr♥ ♥

t r♠♥♥ t♦ rr ♦r rr ss♥ r s ♣♣ t strt tr♠s r

s♠♥②t② ss♠ tt t ♦♦r♥t ♦ ♣♦♥t ♦ ♥trst s x(xi = x, y, z)

♥ ♣②s s♣ ξ(ξi = ξ, η) ♥ ♣r♠tr s♣ ♦ ❯ ss ♥t♦♥s ξ(ξi = ξ, η) ♥

♣r♥t s♣ [−1, 1]× [−1, 1] ♦r t ②♣rs♥r ♥tr ♦ t ♦r♠

I = =

SH(s,x(ξ))R(ξ)J(ξ)S,

r H(s,x(ξ)) s t ②♣rs♥r r♥ R(ξ) s t ❯ ss ♥t♦♥ ♥ J(ξ) s t

♦ tr♥s♦r♠t♦♥ r♦♠ ♣r♥t s♣ t♦ ♣②s s♣ r ♣♦r ♦♦r♥ts

ρ(ρ, θ) ♥tr t t s♦r ♣♦♥t r ♥tr♦ ♥ t ♣r♥t s♣ ♣r♥t ♦♠♥ s

s ♥t♦ tr♥s ♦r qrtr ♥tr② ♦r ♣♦♥t ξ ♥ t str♥s

ξ = ξs + ρ♦sθ,

η = ηs + ρs♥θ,

tr t ♣♦r ♦♦r♥t tr♥s♦r♠t♦♥ qt♦♥ ♦♠s

I = limε→0

∫ 2π

0

∫ ρ(θ)

α(ε,θ)H(ρ, θ)R(ρ, θ)J(ρ, θ)ρρθ,

r ρ(θ) = h/♦sθ h s t s♦rtst st♥ r♦♠ t s♦r ♣♦♥t t♦ t ♠♥t ♥

θ s t ♥ r♦♠ ♣r♣♥r rt♦♥ t♦ t ♣♦♥t s ♥ r ♥ θ0 s

t ♥ ♦ t ♣r♣♥r ♥ t♥ t ♥ t♦ t ♣♦♥t ♥ ♦♠♣t s

θ = θ + θ0.

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r r♥s♦r♠t♦♥ t♥ ♦♦r♥t s②st♠ ♦r

♥tr♥ F (ρ, θ) = H(ρ, θ)R(ρ, θ)J(ρ, θ)ρ s ①♣♥ s

F (ρ, θ) =F−2(θ)

ρ2+F−1(θ)

ρ+ F0(θ) + F1(θ)ρ+ F2(θ)ρ

2 + · · · =∞∑

i=−1

Fi(θ)ρi.

rst t♦ s♥r tr♠s ♦♥ t rt ♥ s r strt ♥ s♠

♥②t② rst♥ ♥

I = I1 + I2,

I1 =

∫ 2π

0

∫ ρ(θ)

0

[

F (ρ, θ)− F−2(θ)

ρ2− F−1(θ)

ρ

]

ρθ,

I2 =

∫ 2π

0I−1(θ)♥

ρ(θ)

β(θ)θ −

∫ 2π

0I−2(θ)

[ γ(θ)

β2(θ)+

1

ρ(θ)

]

θ,

r I1 s rr ♥ I2 r rr ♥ ♥trs ♦t ♥ ♣♣ t ss♥ qr

tr r t♦♥ ♦ α(ε, θ) β(θ) ♥ γ(θ) s s t ♠t♥ ♣r♦ss r ♥ ♥

♣♣♥① ♥ ♠♦r ts ♥ rrr ♥ ❬❪

♦♥♦r♠ ♠♣♣♥ ♦r

t s ♥ r ② ♦♥ t ❬❪ tt t ①♣♥s♦♥ ♦♥ts Fi(θ) ♥ qt♦♥

①ts r♦s ♦rrs ♦ ♥rs♥rt② ♥ t ♥r θ rt♦♥ t♦ t s♥rt②

♥ t r ρ rt♦♥ s ♥ ② ♥ s ♥rs♥rt② s s♥st t♦ t s♣

♦ t ♠♥t ♥ ♦♠s sr ♥ t ♠♥t s ② st♦rt Fi(θ) ♥

r♣rs♥t s

Fi(θ) =Fi(θ)

Ap(θ)=

Fi(θ)

[0.5(|ms1|2 + |ms

2|2)(ωs♥(2θ + ϕ) + 1)]p/2,

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r Fi(θ) r t rr tr♦♥♦♠tr ♥t♦♥s ♥ ♥tr ❵p s t ♦rr ss♦t t

❵i r♥r ss t♦rs msi = mi|ξ=ξs

, (i = 1, 2) ♥ r t s

m1 =[∂x

∂ξ,∂y

∂ξ,∂z

∂ξ

]

,

m2 =[∂x

∂η,∂y

∂η,∂z

∂η

]

.

♥tr♦♥ t♦ ♣r♠trs

λ = |ms1|/|ms

2|,

♦sψ = ms1 ·ms

2/|ms1||ms

2|,

s tt

ϕ = rt♥λ2 − 1

2λ♦sψ,

ω =

1− 4s♥2ψ

(λ+ λ−1)2< 1.

♥ t ♥ ♦♥ tt ♥ t ♠♥t s♣t rt♦ s r ♦r ♥ t♥ t♦

ss t♦rs t♥s t♦ 0 ♦r π s♥ψ → 0 A(θ) t♥ t♦ 0 rst♥ t ♥rs♥rt② ♦

Fi(θ) ♦t s♥r♦s ♥t st♦rt s♣ ♦ t s♥r ♠♥t r ♦♠♠♦♥

♣♥♦♠♥♦♥ ♥ s♦♦♠tr ♥②ss

♦♥ t ❬❪ ♦♥strt t ♦♥♦r♠ ♠♣♣♥ r♦♠ t ♣r♥t s♣ (ξ, η) t♦ ♥

♣r♠tr s♣ (ξ, η) r t t♦ r ♥r ss t♦rs ♥ t ♥ ♣r♠tr s♣

r ♦rt♦♦♥ ♥ ♥t ♥t t♦ ♦tr

ms1 · ms

2 = 0,

|ms1| = |ms

2|.

♥ A(θ) ♦♠s ♦♥st♥t ♠s t ♥trt♦♥ ♥♦♥s♥st t♦ t ♠♥t s♣

t srs s ①♣♥ ♥ t ♥ s♣ qrtr ♦r t s♥r ♥tr tr♥s t♦

st rrss t st♦rt ♠s

♠♣♣♥ ♣r♦♣♦s ② ♦♥ t s t♦r ♦r tr♥r ♠♥t ♥ ts ♦r ①t♥

t ♥t♦ t qrtr ♠♥t r ♥ ❬❪ t ♦♥ tr♥s♦r♠t♦♥ ♠tr① T

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r♦♠ (ξ, η) t♦ ♥ ♣r♠tr s♣ (ξ, η) s

T =

1 δ1

0 δ2

, s♦ tt ξ = Tξ,

r δ1 = ♦sψ/λ δ2 = s♥ψ/λ ♥ t ♥ ss t♦rs

[

ms1 m

s2

]

=

[

ms1 m

s2

]

T−1 =

[

ms1 −(δ1/δ2)m

s1 + (1/δ2)m

s2

]

sts② t rt♦♥ ♥ qt♦♥s ♥r ♥tr♣♦t♦♥ s s r♦♠ (ξ, η) t♦ t

♥ ♣r♠tr s♣ (ξ, η) ♦r qrtr ♠♥t

ξ =

4∑

I=1

NI(ξ)ξI,

N1 = 0.25(ξ − 1)(η − 1),

N2 = 0.25(ξ + 1)(η − 1),

N3 = 0.25(ξ + 1)(η + 1),

N4 = 0.25(ξ − 1)(η + 1).

♦♠♥♥ qt♦♥s ♥ t ♥♦ ♦♦r♥ts ξI♥ ♦t♥ s ξ

1(1+ δ1, δ2)

ξ2(−1+ δ1, δ2) ξ

3(−1− δ1,−δ2) ♥ ξ

4(1− δ1,−δ2) t s♦ ♥♦t tt s♥ 0 < ψ < π

δ2 > 0 t qrtr ♠♥t s r♥t t♦ ♣♦st r ♦♥ ♣♦ss ♣♦t s s♦♥

♥ r s rqrs t s♦r ♣♦♥t s♦ ♥♦t ♦t ♥ t ♥rt ♣♦♥t

♥ t ♦♠tr② r |msi | 6= 0

t ♥ rrr r♦♠ r tt t s♣ ♦ t ♠♥t ♥ ♦♥♦r♠ s♣ s ♦♥tr♦

② t ♦♥ts δ1 ♥ δ2 s ♠♥s tt λ rt ♠♥t s♣t rt♦ ♥ ♦sψ

rt ♠♥t st♦rt♦♥ t r♦♠ t ♦♥♦r♠ ♠♥t s s rst

♥ str♥s t θ ♣♣r♦s t♦ ±π/2 t ♣♦♥t ♦s t♦ t s ♥t t♦ t

s♦r ♣♦♥t ♦ t str♥s r s ρ(θ) = h/♦sθ s ♥♦t t rt②

♦ t ts ♥r s♥rt② ♥ ρ(θ) t ♦♦♥ ♠♦ tr♥s♦r♠t♦♥ s ♣♣ ♥

t ♥r rt♦♥ s tt t ♥trt♦♥ ♣♦♥ts str t♦ t s r t

♥rs♥rt② s sr ♣t② ♦r♥ t♦ t θ ❬❪

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w(θ) =1

π

(

θ +π

2

)

, θ ∈ (−π2,π

2), z ∈ (0, 1)

z = z(s) = w(θ1) +1

2(s+ 1)(w(θ2)− w(θ1)), s ∈ (−1, 1), z ∈ (z(θ1), z(θ2)) ⊂ (0, 1)

f(z) =zm

zm + (1− z)m,

θ = πf(z)− π

2,

J−1(θ) =∂θ

∂s=π[w(θ2)− w(θ1)]mf(z)

m−1

2(f(z)m + (1− f(z))m)2,

r s s t ss ♣♦♥t r♦♠ ♥tr (−1, 1) t rt♦♥ ♦ θ ♥ θ ♥ ♦♥ ♥ qt♦♥

♠r qrtr

♥ ♥♠r ♠♣♠♥tt♦♥ ss♥ r s ♣♣ ♥ ♦t r ♥ ♥r rt♦♥

ss ♣♦♥ts r s ♥ t r rt♦♥ ss ♣♦♥ts r s ♥ ♥r rt♦♥ ♦

str♥ ♦r ♦♥♦r♠ ♥ss s♣ ♣rtr② ♦r ♥♦♥s♥r ♠♥t

♥ ♣t ss♦♥ s♠ s s ♦r♥ t♦ t rt st♥ t♥ t ♠♥t

♥ ♦♦t♦♥ ♣♦♥t t rs r s ♠♣r② t♦t ♥② rr♦r ♦♥tr♦ ♦rt♠

r r♦t

♣♣r♦s s t♦ r♣rs♥t ♥ tr t r ♣r♦♣t♦♥ ♥ ss ♥t♦ t♦

♠♥♦s t ♠♣t ♠t♦ ♥ t ①♣t ♠t♦ t②♣ ♣♣t♦♥ ♦ t ♦r♠r

♠t♦ ♦ t st ♠t♦ ❬❪ s ♦♣ ♥ t ❳ t♦ r♣rs♥t

♥ ♦ t s♦♥t♥t② ❬❪❬❪ st ♥t♦♥ s s♥ st♥ ♥t♦♥ t♦

t r sr ♥ ♦♥ t ♥r②♥ ♠s ♦ ♦♥sst♥t t t ♠s

srt③t♦♥ ♦ t ♣r♦♠ ♦r ♥♣♥♥t strtr ♠s ♥ t rs r ♦♣♥

srs ♦♥ ♠♦r st ♥t♦♥ s♦ ♥ ♣r♣♥r t♦ t r sr

s rqr ♥ ♦rr t♦ sr t r r♦♥t qt② t♦ r♣rs♥t t r sr

♣♥s ♦♥ t rs♦t♦♥ ♦ t ♥r②♥ ♠s rt② sr♥ t r sr

s② ♥tr♦s t♦♥ ♦♠♣tt♦♥ ①♣♥s ❬❪ t♦♥t②♣ qt♦♥s s♦

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s♦ s♦ s t♦ ♣t t r r♦♥t ♥ t r ♦s ❬❪ ♥rss t

♦♠♣tt♦♥ ♦rt ♦♣♣ ♥ ♠r ❬❪ ♣r♦♣♦s t st ♠r♥ ♠t♦ t♦ ♣t

t r r♦♥t ♦t♦♥ ts tt♥ t ♣r♦ss ♦ ♣t♥ t r sr ❬❪ rs

♥ ②♦♥ ❬❪ ♣r♦♣♦s ♥ ♠♣t①♣t ♠t♦ ♥ t st r♣rs♥t r

s ①♣t② rt③ ② tr♥r ts sr ♥♦♦s ♣r♣♦s ♦ t t♦r

st ♠t♦ ❬❪ s ♠t♦s t ♥t ♦ t st r♣rs♥tt♦♥ ♦r t P❯

♥r♠♥t ♦♥ t♦ ♣t t r sr ② s♦♥ t qt♦♥s t♦♥②

sr♣ tr♥s ♥ ♥s ♥ rt♥ ② s ♦ ①♣t r srs rtr t♥ ♣r

sts

ttr ♠t♦ ss sts ♦ tr♥r ♦r qrtr ts t♦ srt③ t r sr

rt② ♦r ♥t ♠♥t s ♠t♦s t r ♦t♦♥ ♣r♦ss s s② ♦♠♣♥

t t♦♠t r♠s♥ ♦♣rt♦♥ ♦r ❳ ♣♣t♦♥s t ss♦♥ ♦ t

s♦ ♠♥ts ♥s t♦ ♣r♦r♠ ♦r t ♥trt♦♥ ♣r♣♦s ♦t r② ♦♥

♦♣ ♠s♥r♠s♥ ♣s ❬❪❬❪ ①♣t r♣rs♥tt♦♥ ♦ r srs

② tr♥t♦♥ s ♥ s ♥ ♠sr ♠t♦s s ❬❪ t s♦ ♥♦t tt ts

r♣rs♥tt♦♥ ♠t♦ s② rsts ♥ C0 r sr ♥ t r r♦♥ts r ♦♠♣♦s

♦ ♥ s♠♥ts s t♦ t st t♦ s♦rt♦♠♥s t r r♦♥t s ♥♦t ♣

tr ①t② ♥ ♦♠♣tt♦♥ s♣t ♥ ts ♥r② ♥ t ①trt♦♥ ♦ t

rtr ♣r♠trs ♦r ①♠♣ t s r♦♠ t ♥♠r s♦t♦♥ ♥ ♦♠tr② ♣♣r♦①

♠t♦♥ rr♦r ♠t t t r r♦t t ♦ r r♦♥t ♦♦r♥t

s②st♠ s ♥♦t ♥ ♥ t t♦♥ ♥ s s♦♥t♥♦s rst♥ ♥ t ♥♦♥♥q

r♥ ♥r♠♥t ♦r s♦♠ ♦ t♣ ♥tr ♦♥ t r r♦♥t ♥ss t r♥ ♥r♠♥t

s ♥♦♥ ❬❪ s r♠② t r r♦♥ts ♥ t♦ s♠♦♦t tr♦ s♦♠ ♥♠r

t♥qs ❬❪❬❪ ♠r s♥r♦ ♦rs ♥ r♥ s ♦r rtr ♠♦♥

ss Ps③♥② ♥ ❩♠♠r♠♥ ❬❪ ♣♦♥t ♦t tt r ♥♠rs ♦ ts r ♥ ♥ ♦rr

t♦ ♠♦r rt② r♣rs♥t t r sr ♥ t st♦r ♥rss r♣② t rs♣t t♦

t r ♦ t r sr ♥ r ♣r♦♣ts ♥ t② ♣r♦♣♦s t s ♦ ♣r♠t

r sr t ❯ ♣t t♦ sr t r ♣r♦♣t♦♥ ♥ tr ♣♣r♦ t

r r♦t s r③ ♦♠tr② ② ♦r♠♥ t ❯ sr tr♦ t ♠r♥

r ♦rt♠ ❬❪ t♦ ♠♦ t ♦♥tr♦ ♣♦♥ts t♦ t ♣r♠tr③t♦♥ ♦ t ❯

♣t t r t♣ ♥ s♠♣ ♥②r ♦♥ t r r♦♥t ts t st♦r ♦r r

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r r r♦♥t ♣t♥ C(ξ) s t ♦ r r♦♥t r C′(ξ) s t ♥ r r♦♥tr tr trt♦♥

srt③t♦♥ ♥rss ♠② ♥ t ♦ r r♦♥t ♦♦r♥t s②st♠ s sts

♦♥ t s♠♦♦t ♦♠tr② ♦r ts ♠t♦ s ♦♥ r♠s♥ t ♥t ♠♥ts

♠s r♥rt♦♥ ♥s t♦ r② ♦♥tr♦ t♦ ♥sr t ♠s qt② ♥t② ♠t

t ♣r♦♣♦s ♥ ①♣t② r♣rs♥t ♦r♠♥s♦♥ ♦♠tr② trs ② ❯ ❬❪❬❪

tr♦ t ♣rtt♦♥ ♦ ♥t② ♣♣r♦①♠t♦♥ ♥st ♦ s♥ sts t ♦r♠♥s♦♥

trs s s rs r rt② sr tr♦ t t♦♥ ♦ t st♥ ♥

♥ ♥t ♥♦♥trt ② ♣r♦♥ ♣r♦♠s♥ tr♥t t♦ ♦ s♦♥t♥t② ♥ t

r♠♦r ♦r ♠♦r st ♥♠r qrtr s♠ s sr ♥ ♦rr

t♦ ② ①♣♦t t ①t r♣rs♥tt♦♥ ♥ ♦♠tr②

♥ t ♣rs♥t ♦r s ❯ ♣ts t♦ srt③ t r srs r r♦♥t

s ①t② sr ♥ t ♦ r t♣ s②st♠ s ♥ ♥tr② ♥ ♥q② s ♦♥

t ❯ ♣t ♥ t ♣②s q♥tts r s♦ ♣♣r♦①♠t ② t ❯

ss ♥ t s♣rt ♦ s♦♦♠tr ♥②ss ♦♠♥♥ t t s♠♦♦t♥ss ♥ ♦♠tr②

♥ strss s♦t♦♥ s ② ①♣♦t t♦ t t rtr ♣r♠trs ♥ ♦ t r

♥ st ♠♥♥r

r sr ♣t♥ ♦rt♠

r ♣r♦♣t♦♥ s r③ ♦♠tr② ② ♥♥ t r r♦♥t s♦ tt t ♥ r

r♦♥t r C′(ξ) s ♣ss tr♦ t ♥ ♣♦st♦♥s ♦ t s♠♣ ♣♦♥ts ♦♥ t ♦ r r♦♥t

r C(ξ) s ♣r♠tr③ ② t ♥♦t t♦r Ξ = ξ1, ξ2, ..., ξn+p+1 n s t ♥♠r

♦ ss ♥t♦♥s ❲ ♥ t s♠♣ ♣♦♥ts ♦♥ C(ξ) t♦ Mj = M(ξj), j = 0, 1, ..., N − 1

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♥ t st ♦ ♦rrs♣♦♥♥ ♥ ♣♦st♦♥s t♦ M ′j N ♥ ♣♦st♦♥s ♦ s♠♣ ♣♦♥ts

r sr s t ♦♥str♥ts r♥ t ♦r♠t♦♥ ♣r♦ss r♦♠ C(ξ) t♦ C′(ξ) ♥ st

N = n r ❲ ♦♣t t ♦rt♠ sr ♥ ❬❪ ♥ ts ♦rt♠ t ♦r♠t♦♥ ♦

r ♥r ♠t♣ ♦♥str♥ts s trt♦♥ ♣r♦ss ♦r tt trt♥ st♣ ♥ t

rr♦r t♦r s

ej,t =−−−−→Mj,tM

′j .

‖et‖ < tol t trt♦♥ ss ♥ t ♥ r r♦♥t r s ♦t♥ tol = 1.e − 4 ♥

ts ♦r

♦ ♣t t ♦♥tr♦ ♣♦♥ts Pi, i = 0, 1, ..., n− 1 ♥ ♠♦♠♥t t♦r m s tt ♥

tt trt♥ st♣

Pi,t = Pi,t−1 +mi,t

♠♦♠♥t t♦r mt ♥ ♦♠♣t s

mi,t =1

N

N−1∑

j=0

fijej,t−1,

r fj = f(ξj) r t ♥♥ ♥t♦♥s ♦rrs♣♦♥♥ t♦ ♦♥str♥t M ′j ❲ ♦♦s

t ♥♥ ♥t♦♥s t♦ t ❯ ss ♥t♦♥s r s t♦ sr t r

fj = Rj ♦ ♠ sr t ♥♥ ♥t♦♥s fij = fi(ξj) ss♦t t ♦♥str♥t

M ′j r ♥r② ♥♣♥♥t s♦ tt t ♦♥str♥t s t t♦ t ♦r♠t♦♥ ♦ t r

t ♣r♠tr ♦♦r♥t ξj ♦ Mj s♦ sts② ξj ∈ [ξi, ξi+p+1] s s t r

sss t♦ ♥rt t s♠♣ ♣♦♥ts

♥② t rr♦r t♦r s t ♥ rrs ②

ej,t = ej,t−1 −1

N

N−1∑

k=0

〈Rj , fk〉ek,t−1

ts ♦r ♣t♥ t r r♦♥t s ♥ ♥ ♦rt♠ ♥ t ♥ r r♦♥t

r s ♦t♥ t ♥ r srs ♥ ♥rt ② ♦t♥ ♦♥ t r ①t♥s♦♥

rt♦♥ r♦♠ t ♦ r t♦ t ♥ r ♥rt r srs s ♠r

♥t♦ t ♦ r srs t C0 ♦♥t ♦r C1 ♦♥t ♥ ts ♦r C0 ♠r s ♦♣t

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♦rt♠ r r♦♥t ♣t♥ ♦rt♠

t ♦ r r♦♥t r C(ξ) s♠♣ ♣♦♥ts Mj ♥ ♣♦st♦♥s ♦ s♠♣ ♣♦♥ts M ′j

st ♥ r r♦♥t r tt ♣sss tr♦ M ′j

t = 0tol = 1.e− 4

ej,0 =−−−−−→Mj,0M

′j

‖et‖ > tol ♦t = t+ 1mi,t =

1N

∑N−1j=0 fijej,t−1

Pi,t = Pi,t−1 +mi,t

ej,t = ej,t−1 − 1N

∑N−1k=0 〈Rj , fk〉ek,t−1

♦♠♣tt♦♥ ♦ strss ♥t♥st② t♦rs

r♥ ♦r ♦r t ♦t♦♥ ♦ t rtr s rtr③ ② s♦♠ rtr ♣

r♠trs s s t strss ♥t♥st② t♦rs s ♥ ①trt r♦♠ t ♥♠r

s♦t♦♥ t rtr ♣r♠trs r ♦♠♣t s ♦♥ t ♣♦♥ts t♣s ♦♥ t r

r♦♥t ♥♣♥♥t② t ♥ rr s ♦ ♣♣r♦ ② t♦r t♦ ♦♠♣t

rt② t s ♥ t ♦ ♣♣r♦ s t♦ ♦ t srt③t♦♥ ♥ ♣t ♣♥♥ s

♠ s ♣♦ss ❱r♦s ♠t♦s ♥ ♦♣ t♦ ①trt t s ♥ t r♠♦r

♦ ♥ s♣♠♥t ♦rrt♦♥ ♠t♦ ❬❪ t ♦r t♦t t rt♣

s♥r ♠♥t s s♠♣ ♥ st ② ♦r ts ♠ rtss ♣t ♣♥♥ ♦

ts ♠t♦ ♥ ♥♦t ♥t ♥ ♥ ①tr♣♦t♦♥ t♥q s ♣r♦r♠ ♣♦♥ r♦♣ ♦

t♦♥s rt r ①t♥s♦♥ ♠t♦ ❱ ❬❪❬❪ s ♣♣ t♦ ♦♠♣t s

s ♦♥ t t♦♥ ♦ t rs str♥ ♥r② ♣r rt r ①t♥s♦♥ ♦r♥

❱ rs ♦♥ t ♦♥strt♦♥ ♦ strtr ♠s ♦♥ t r r♦♥t ♥rss t

♠s r♥ ♦r t s♦ ♥♦t tt t rt♦♥ ♦r♠ ♦ t str♥ ♥r②

♥♦s t ♥r② rs rt ♥ t r ①t♥s♦♥ s ♥ ♣♣ ♦r t♦♠t r

r♦t ❬❪❬❪ r t r ①t♥s♦♥ s ss♥ t ♣②s ♥tr♣rtt♦♥ s ♠t♦

♠♥♠③ t str♥ ♥r② ♥ ♦ s♥s ts ♥ t♦ s♥♥t r♥ r♦♠ ♦

♣♣r♦ ♥ s r♥t② ♥ ♥stt ♥ t r♠♦r ♦ ❳ ❬❪

rt r ♦sr ♥tr ❱ ♠t♦ s ♣r♦♣♦s s ♦♥ t rt r ①

t♥s♦♥ s ♥♦tr tr♥t t♦ ①trt s ♥ ♥r st rtr t♦ t s♠♣t②

♥ r② t ❱ s ♥ ② s ♥ ♥ ❬❪ ❲ t s♦ ♥♦t

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r r t♣ ♦♦r♥t s②st♠

tt ts ♠t♦ rqrs t ♠♥t ♥r t r r♦♥t ♥ ♥ ♦♥sst♥ t t ♥♦r

♠ rt♦♥ ♦ t r r♦♥t ♣t♥♣♥♥t J ♥tr ♣r♦♣♦s ② ❬❪ s ♥

ttrt ♠t♦ t♦ ts r♦st♥ss rr♥ t rt ♥♣♥♥ ♥ srt③t♦♥

♥ ♣t ♦ ♥tr ♠t♦ s♦♦♥ s ①t♥ ♥t♦ ♠♥② r♥s ♥ ♦♦

rsts ♥ ♦t ♥ ❬❪❬❪❬❪❬❪❬❪ ♦♥t♦r J ♥tr s s t♦ st ♥t♦

t q♥t ♦♠♥ ♥tr ♦r♠ ♥ s t ♥♦ strss s ♥♦t strt♦rr s♦t♦♥

♥ rqr♠♥t ♥ ♠s srt③t♦♥ s r① ❲ ♥ t ♦♥t♦r ♥t♦♥ ♥

♦♣t rt② ❬❪ ♥ ♦rr t♦ ①trt ♠① ♠♦ s r♥t t♥qs r ♦♣

Jx ♥trs x = 1, 2, 3 s t ♦♠♣♦♥♥ts ♦ J ♥tr ♥ rt② s t♦ t

t s ♦r t t♦♥ ♦ J2 ♥ J3 ♦r GIII ①ts ♥♠r t② t♦

t s♥rt② ❬❪ J1 ♥tr ♦r J ♥tr ♥ s♦ ♥ s t♦ ①trt ♠① ♠♦

s t s♦♠ ①r② ♦♣rt♦♥ ♥ ② s t♦ ♦♠♣♦s t s♣♠♥t ♥ strss

s ♥t♦ s②♠♠tr ♥ ♥ts②♠♠tr ♣♦rt♦♥s t strtr ♠s ♦♥ t r r♦♥t

t♥ tr ♠♦s ♦ J ♥tr ♥ t rt② ❬❪❬❪❬❪❬❪ ♦tr ♠t♦

♥♠ M ♥tr ♦r ♥trt♦♥ ♥r② ♥tr s ♦♣ ② ♥tr♦♥ s②♠♣t♦t

s s t ①r② s♦t♦♥ ❬❪ s ♥ ①t♥ ♥ ❳ ❬❪❬❪ ♥ ❬❪

♦t t ❱ ♥ ♦♥t♦r M ♥tr ♥ ♥stt ♦r t t♦♥ ♦ s ♥

t rtr ♥②ss s♦♦♠tr ♣♦♥ts r t♣ ♦♦r♥t s②st♠ s

sts ♦♥ t r r♦♥t s ♥ r ♣②s q♥tts r ♥ t r t♣

♦ ♦♦r♥t s②st♠ ts t s♣rsr♣t ❵♦ s ♦♠tt ♥ ts st♦♥

♦♥t♦r M ♥tr

♥t♦♥ ♦ Jk ♥tr st♠s r♦♠ t♦ ♠♥s♦♥s s

Jk := limΓǫ→0

Γǫ

(Wδjk − σijui,k)njΓ = limΓǫ→0

Γǫ

PkjnjΓ, k = 1, 2

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r Pkj s t s② t♥s♦r W = 1/2σijǫij s t str♥ ♥r② ♥st② Γǫ s s♠

♦♥t♦r t rs R ♥tr t r t♣ ❵o ♥ t ❵xo − yo ♣♥ ♥ nj s t ♥t ♦tr

♥♦r♠ ♦ Γǫ

t ♥ ①t♥ t♦ tr ♠♥s♦♥ ♣♦♥ts ♥t♦♥ ② t♥ tr sr r♦♥

t r r♦♥t ❲♥ t ♦♥t♦r Γǫ s s♠ ♥♦ t ♣♥ str♥ ♦♥t♦♥ s ♣♣r♦①

♠t② sts ❲ ♦ s t ♦♥t♦r ♥t♦♥ rt② ♦♥ t ♣r♠s tt s♠

♦♥t♦r s ss♠

t s ♥♦♥ tt t J ♥tr J1 ♥ t s t rt♦♥s♣

J = GI +GII +GIII =1− ν2

EK2

I +1− ν2

EK2

II +1

2µK2

III ,

r Gi ♥ Ki i = I, II, III r t ♥r② rs rts ♥ s ♦r t tr ♠♦s ♦

rtr

② ♣♣②♥ t J ♥tr ♥r t♦ stts ♦♥ t r stt ♥♦t t s♣rsr♣t ❵

t ♦tr t ①r② stt s♣rsr♣t ❵ t♥ ♥ t♠ t♦tr t ♠① tr♠ M

♥ ♦t♥

J (1+2) =

Γǫ

[

0.5(σ(1)ij + σ

(2)ij )(ǫ

(1)ij + ǫ

(2)ij )δ1j − (σ

(1)ij + σ

(2)ij )

∂(u(1)i + u

(2)i )

∂x1

]

njΓ

rr♥♥ t t♦ stt tr♠s s

J (1+2) = J (1) + J (2) +M (1,2)

r

M (1,2) =

Γǫ

[

W (1,2)δ1j − σ(1)ij

∂u(2)i

∂x1− σ

(2)ij

∂u(1)i

∂x1

]

njΓ

W (1,2) = σ(1)ij ǫ

(2)ij = σ

(2)ij ǫ

(1)ij

♦♠♥ t qt♦♥ t ♦♦♥ rt♦♥s♣ ♥ ♦t♥ ♦r t M ♥tr

M (1,2) =2(1− ν2)

E(K

(1)I K

(2)I +K

(1)II K

(2)II ) +

1

µK

(1)IIIK

(2)III .

♥ s ♥ ①trt rs♣t② ♦r ①♠♣ t stt t ♣r ♠♦ III s②♠♣

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t♦t s t K(2)I = 0 K

(2)II = 0 K

(2)III = 1 ♥ KIII ♥ r stt 1 ♥ ♦♥ s

K(1)III = µM (1, ♠♦ III)

KI ♥ KII ♥ ♥ ♥ s♠r s♦♥ r t rst ♦rr s②♠♣t♦t s♣♠♥t ♥

strss s♦t♦♥s s ♣♣♥① r st s t ①r② s

❱rt r ♦sr ♥tr

♥ t ❱ t str♥ ♥r② rs rt s q t♦ t ♦r ♦♥ ② ♦s♥ t rt

r ①t♥s♦♥ r ♠♦s ♦ t str♥ ♥r② rs rt r ♥ ②

GI =1

2R

∫ R

0σyy(x)Juy(R− x)Kx,

GII =1

2R

∫ R

0σxy(x)Jux(R− x)Kx,

GIII =1

2R

∫ R

0σyz(x)Juz(R− x)Kx,

r OP ′ = R s t rt r ♥ ♦r t t♦♥ ♦ Juj(R − x)K ♦♥ PO t

♣♦♥t ♥rs♦♥ ♦rt♠ ♥s t♦ ♣r♦r♠ ♥ ♦rr t♦ ♥ t ♣r♠tr ♦♦r♥t ♥

t r ♠♦ ② ❯ sr ❬❪ ♦♠♥s ♦ ts ♥trs OP ′ ♥ PO r

rt③ ② s♥ ♥r ♠♥t ❬❪ ♥ t R s ♥t ♦r t r t♣s ♥ KI

KII ♥ KIII ♥ ♦♠♣t ♦r♥ t♦ qt♦♥

Prs

Prss s ♥ s t♦ sr t st② stt r r♦t ♥ t t

r ♣r♦ss ❲ s t ♦r♥ Prs s ♦♦s

a

N= C(∆K)m,

r N ♥♦ts t ♥♠r ♦ ♦ ②s C ♥ m r t ♠tr ♣r♠trs ∆K s t

r♥ ♦r ♠① ♠♦ r t K s t♥ s t q♥t Keq s ♥ s

❬❪

Keq =√

K2I +K2

II + (1 + ν)K2III

Page 23: Isogeometric boundary element methods for three dimensionalorca.cf.ac.uk/102950/1/102950 - Isogeometric boundary... · 2021. 1. 20. · Isogeometric boundary element methods for three

❲ s♣② t ♠①♠♠ r ♥ ∆amax s♦ tt t ♥♠r ♦ ♦ ②s ♥

♦t♥ ♦r♥ t♦ t t s♦ ♥♦t tt t r ♣r♦♣t♦♥ ♦t② ♦

r ♦r t r t♣s ♦♥ t r♦♥t ♥ s♥ ♣r♦♣t♦♥ st♣ t r ♥ ♦r

r t♣ s rr③ ② t ∆amax

∆ai = C(∆Kieq)

m ∆amax

C(∆Kmaxeq )

= ∆amax( ∆Ki

eq

∆Kmaxeq

)m.

♠①♠♠ ♦♦♣ strss rtr♦♥ s s t♦ tr♠♥ t rt♦♥ ♦ r ♣r♦♣t♦♥

❲ ss♠ tt t r ♣r♦♣ts ♥ t rt♦♥ θc s tt t ♦♦♣ strss s ♠①♠♠

s ♥ ② t ♦♦♥ ①♣rss♦♥ ❬❪

θc = 2rt♥

[

−2(KII/KI)

1 +√

1 + 8(KII/KI)2

]

.

♠r ①♠♣s

♥ ts st♦♥ ♥♠r ①♠♣s ♦t t ♣♥♥②s♣ r ♥ ♣t r

♥ ♠♦ ♥ ♥♥t ♦♠♥ t t qt♦♥ ♥ ♥ ♥t ♦♠♥ t t

qt♦♥s ♥ ♦♥r♥ ♥ s ♦♠♣r ♥ t ♥♠r s r

t ② ♦t ❱ ♥ M ♥tr ♥ t r r♦t ♦rt♠ s

❨♦♥s ♠♦s E = 1000 ♥ P♦ss♦♥s rt♦ ν = 0.3 ♦r t ss

P♥♥②s♣ r

♣♣♦s ♣♥♥②s♣ r s st t♦ t r♠♦t t♥s♦♥ σ0 t∞ = (0, 0, σ0)

rs ♦ r s a ♥♥t♦♥ ♥ s ϕ ♥ rr ♥ θ s ♥ ♥ t r ♣♥

Oxy s ♥ r ♥②t s♦t♦♥ ♦ s rs

KI =2

πσ0

√aπ♦s2ϕ,

KII =4

π(2− ν)σ0

√aπ♦sϕs♥ϕ♦sθ,

KIII =4(1− ν)

π(2− ν)σ0

√aπ♦sϕs♥ϕs♥θ.

Page 24: Isogeometric boundary element methods for three dimensionalorca.cf.ac.uk/102950/1/102950 - Isogeometric boundary... · 2021. 1. 20. · Isogeometric boundary element methods for three

r ♦♠tr② ♦r ♣♥♥②s♣ r a = b ♥ ♣t r a 6= b

♥ ♣rtr ♥ t r ♣♥ s ♦r③♦♥t ϕ = 0 t ♥②t ♥♦r♠ s♣♠♥t

s ♥ s

uz(r, θ, 0) =2(1− ν)σ0

πµ

a2 − r2, r 6 a.

♥r ♥trt♦♥ tst

♣r♦♠ s ♠♦ ② qt♦♥ s♦ tt ♦♥② s♥ ❯ ♣t s s t♦

r♣rs♥t t r ♥ t ♥♠r ♦♠♣r t t ♥②t s♦t♦♥

♦♦t♦♥ ♣♦♥ts r ♠♦ s r♦♠ t ♣♦ ♥ ♦rr ♥♦t t♦ ♦t t t ♥rt ♣♦♥t

❯ ss ♥t♦♥s ss♦t t t ♣♦ ♦r r ♥♦r t♦ C0 tr♦ t

♦rrs♣♦♥♥ ♦♥tr♦ ♣♦♥ts sr♥ t s♠ rs ♦ r♦♠ s r♦♠ ts ♠♦

♦♦t♦♥ ♣♦♥ts r ♠r t♦ ♦♥ qt♦♥

❲ ♥♦t tt t s♦t♦♥ ♦♥② rs ♥ r rt♦♥ ♣♥ t s♠ ♥ ♥r

rt♦♥ ts ♠♥ts r s ♥ ♥r rt♦♥ s t♦ s♣t rt♦ ♦

♠♥t t t r♥♠♥t ♥ r rt♦♥ r ♦♠♣rs t L2 ♥♦r♠ rr♦r

♥ ♦r ϕ = 0 ❵♥♣❴s ♥♦ts t ♥♠r ♦ ss ♣♦♥ts ♥ ♥r rt♦♥ ♥

str♥ ♦r♥ ♠♥s rt s ♦ t ♠t♦ ♥ ♠♣r♦ ♥♦ts t

t ♦♥♦r♠ ♠♣♣♥ t ♥ ♦sr tt

• ♥ ♥♣❴s= 30 t ♦r♥ ♥ ♠♣r♦ t ♦♠♣r rr♦r ♦r

t rr♦r r♦♠ ♦r♥ s ♥♦♥♥♦r♠② strt st t ♠♣r♦ ts

♠♦r ♥♦r♠ rr♦r strt♦♥

Page 25: Isogeometric boundary element methods for three dimensionalorca.cf.ac.uk/102950/1/102950 - Isogeometric boundary... · 2021. 1. 20. · Isogeometric boundary element methods for three

• ♥ ♥♣❴s= 18 t rr♦r r♦♠ ♦r♥ ts r eL2=

♠♣r♦ ♣s t s♠ r② s t r♦♠ ♥♣❴s= 30

• t rr♦r ♦♠s ♥r t r r♦♥t s s t♦ t r t♣ s♥rt②

s ♦♥ tt ♦r♥ ♥ ♠♦r ss ♣♦♥ts ♥ ♦rr t♦ t rs♦♥

r② ♠♦ t ♥♦t η = 0.875 ♥①t t♦ t r r♦♥t ♥ r rt♦♥ ♦sr t♦

t r r♦♥t η = 0.94 ♥ r♣t ♦♠♣rs♦♥ s ♥ r ❲ ♥ tt ♥ ♥♣❴s= 30

♦r♥ st s rr♦r t ♠♣r♦ ♠t♦ s♦s r r② t♥

♦r ❲ ♥ rr tt t♦ t r t♣ s♥rt② r♥ ♠s ♥r t r r♦♥t

s♦ ttr r② ♥ t t ♦r♥ s s♥st t♦ t ♠♥t st♦rt♦♥

♥ s r rsts ♠♣r♦ ♣rs♥ts r♦st ♣♣t♦♥ ♦r ts ♥ ♦

♠s ♦♥rt♦♥

♦r♥ ♥♣❴s eL2= ♠♣r♦ ♥♣❴s eL2

=

♦r♥ ♥♣❴s eL2= ♠♣r♦ ♥♣❴s eL2

r rr♦r ♥ r ♦♣♥♥ s♣♠♥t ♦r ♣♥♥② r ❵♥♣❴s ♥♦ts t ♥♠r♦ ss ♣♦♥ts ♥ ♥r rt♦♥ ♥ str♥ ♥♦t t♦rs ♥r rt♦♥ξ❬❪ r rt♦♥ η❬❪

Page 26: Isogeometric boundary element methods for three dimensionalorca.cf.ac.uk/102950/1/102950 - Isogeometric boundary... · 2021. 1. 20. · Isogeometric boundary element methods for three

♦r♥ ♥♣❴s eL2 ♠♣r♦ ♥♣❴s eL2

♦r♥ ♥♣❴s eL2 ♠♣r♦ ♥♣❴s eL2

r rr♦r ♥ r ♦♣♥♥ s♣♠♥t ♦r ♣♥♥② r ♥♦t t♦rs ♥r rt♦♥ξ❬❪ r rt♦♥ η❬❪

Page 27: Isogeometric boundary element methods for three dimensionalorca.cf.ac.uk/102950/1/102950 - Isogeometric boundary... · 2021. 1. 20. · Isogeometric boundary element methods for three

r ❯p = q = 2 r♣rs♥t r sr ♠ss t ♥ ♥♦r♠r♥♠♥t ♥ r rt♦♥ ♦♦ ② r r♥ ♠♥ts t s ♦s t♦r r♦♥t ♦ts r ♦♦t♦♥ ♣♦♥ts

♦♥r♥ tst

❯♥♦r♠ ♠s r♥♠♥t ♥ t ♣r♠tr s♣ s ♣r♦r♠ ♥ t t ♠♥t

s③ h s h =√

Smaxe r Smax

e ♥♦ts t ♠①♠♠ r ♦ t ♠♥t ♦♥r♥

r s ♣♦tt ♥ r r ♦♠♣r ♦t t qrt ♥ ❯ ss

♥t♦♥s t ♥ ♦♥ tt t r t♦♥ ♣s t♦ ♠♣r♦ t r② t

t ♦rr ♦ ♦♥r♥ rt oc ♣s ♠♦st t s♠ oc = 1 tr♦t oc s

t♦ t ♣②s s♥rt② ♦♥ t r r♦♥t

s stt ♥ t ♦ st♦♥ t ♥♦r♠ r♥♠♥t s ♥♦t ♥ ♥t ② t♦ ♠♣r♦ t

r② ♦r ♣♥♥② r s ♠s ♦♥rt♦♥s r s♥ tr♦ ♣♥ t

♠♥t ♥♠r ♥ ♥r rt♦♥ t ♠s s ♥♦r♠② r♥ t t ♠♥t ♥♠r

♥ ♥ r rt♦♥ t♥ t ♠♥t t r r♦♥t s rtr r② r♥

♦♥st ♥♦t ♥srt♦♥ ♥ ♦rr t♦ r t rr♦r s ② r t♣ s♥rt②

r s♦s ♠s ♥ r ♣♦ts t rst ♦r ♦♥r♥ st② t ♥

s♥ tt t r② s ♠♣r♦ ♠♦st ② ♦♥ ♦rr ♥ t ♥ st♠t ♦♥r♥ rt

s t♦ t♠s r t♥ t ♥♦r♠ r♥♠♥t s ♥ts t ♥② ♦ ♥

t ♣♣t♦♥ ♦ rtr s♠t♦♥

trss ♥t♥st② t♦r tst

♥ ts sst♦♥ t ♦♠♣tt♦♥ ♦ s s ♥st ♦ s♥ qt♦♥ t♦ ♠♦

t ♣♥♥②s♣ r ♥ t ♥♥t ♦♠♥ ♣t t♦ ♦r♣♣ r srs ♥

Page 28: Isogeometric boundary element methods for three dimensionalorca.cf.ac.uk/102950/1/102950 - Isogeometric boundary... · 2021. 1. 20. · Isogeometric boundary element methods for three

10−1

100

10−2

10−1

100

h

L2

no

rm e

rro

r in

CO

D

p=2

p=3

1

0.99

1

1.00

r L2 ♥♦r♠ rr♦r ♦ ♦r ♣♥♥②s♣ r

102

103

10−3

10−2

10−1

100

Degrees of freedom

L2

no

rm e

rro

r in

CO

D

p=2, uniform

p=3, uniform

p=2, graded

0.60

1.41

1

1

0.59

1

r L2 ♥♦r♠ rr♦r ♦ ♦r ♣♥♥②s♣ r

Page 29: Isogeometric boundary element methods for three dimensionalorca.cf.ac.uk/102950/1/102950 - Isogeometric boundary... · 2021. 1. 20. · Isogeometric boundary element methods for three

0.02 0.03 0.04 0.05 0.06 0.07 0.08−0.1

−0.08

−0.06

−0.04

−0.02

0

0.02

0.04

0.06

0.08

0.1

distancegtogcrackgfrontg(R/a)

err

or

VCCI

Mgintegral

r Pt ♥♣♥♥ ♦r ❱ ♥ M ♥tr

t s③ L = 200a s tt ♦ ♦♠♣r t ♥♠r s t t ♥②t s♦t♦♥

♦r ♥♥t ♦♠♥ qt♦♥s r s ♦r ts s

r ♥stts t ♣t ♥♣♥♥ ♦ t ♥tr ♥ ❱ ♦r ♠♦ I ♣♥♥②

s♣ r r ❵R ♥♦ts t rt r ♥ ♥ ❱ ♥ t rs ♦ t ♦♥t♦r

♥ M ♥tr t ♥ s♥ tt ♥ R/a s r♦♠ 0.02 t♦ 0.08 ♦t ♠t♦s s♦ ♣t

♣♥♥t ♦r ♦r M ♥tr t rr♦r rs t♥ ❲♥ t rs ♦ ♦♥t♦r s

s♠ KI ♦♥rs t♦ ♥②t ♥rs♥ R s♥ t strss ♦r t r

t♣ s ♥♥ ② ♦tr t♣s ♥ t r r♦♥t ♣♥ str♥ ♦♥t♦♥ s ♥♦t sts ♣r♦♣r②

t ♠t♦ ♦♠s ♥rt ♦r ❱ t rr♦r rs t♥ ♥ ♥r② s♠

rt r ♥ s ♥ ♦r R s t♦♦ s♠ t② ♥ ♥♠r t♦♥

♦ strss ♥ ♦s t♦ r r♦♥t rs t♦ t ♥r② ♦ KI r♦♠ t

r ♥ s♦ rr tt M ♥tr ♣rs♥ts s♠r rt♦♥ ♥ rr♦r t♥ ❱

r ♦♠♣rs t s ♦t♥ r♦♠ M ♥tr t R = 0.02a ♥ ❱ t R =

0.04a ♦r t ♠① ♠♦ ♣♥♥②s♣ r t ♥♥t♦♥ ♥ ϕ = π/6 t s s♥ tt

♦t ♠t♦s r t t ♥②t s♦t♦♥ KIII r♦♠ M ♥tr s♦s t♦♥

♥r θ = π/2 ♥ 3π/2 ♣rs♥ts t rr♦r t θ = 0 π/4 ♥ π/2 t ♥ ♦sr

tt t rr♦r ♦ KI ♥ KII s t♥ ② ♦t ♠t♦s t♥ ♦r KIII ② M

♥tr ♥ ♦♥ tt t ♥ ♣r♦ rt s ♥ t ♥♠r

Page 30: Isogeometric boundary element methods for three dimensionalorca.cf.ac.uk/102950/1/102950 - Isogeometric boundary... · 2021. 1. 20. · Isogeometric boundary element methods for three

0 1 2 3 4 5 6

−0.4

−0.2

0

0.2

0.4

0.6

θ (rad)

SIF

s

KI

KIII

KII

Analytical

M integral

VCCI

r trss ♥t♥st② t♦rs ♦r ♣♥♥② r t ϕ = π/6

s ♦♥ r r♦♥t s qt s♠♦♦t t♦ t ♦♥② ♠♥ts ♥ ♥r rt♦♥ ♥

t♦t ♥② s♠♦♦t♥ss ♦♣rt♦♥ s s t ♣r♠s ♦r st ♦t♦♥ ♦r t r

r♦t s♠t♦♥

KII KIII

❱ M ♥tr ❱ M ♥tr

θ = 0

θ = π/4

θ = π/2

rr♦r ♦ s ♦r ♣♥♥②s♣ r t ϕ = π/6

♣t r

♣♣♦s ♥ ♣t r s st t♦ t r♠♦t t♥s ♦♥ σ0 ♥ t ♥♦r♠ rt♦♥

t∞ = (0, 0, σ0) s♠♠♦r ①s s a s♠♠♥♦r ①s b ♥♥t♦♥ ♥ s ϕ

♥ ♣t ♥ θ s ♥ ♥ t r ♣♥ s ♥ r ♥②t s♦t♦♥ ♦

Page 31: Isogeometric boundary element methods for three dimensionalorca.cf.ac.uk/102950/1/102950 - Isogeometric boundary... · 2021. 1. 20. · Isogeometric boundary element methods for three

s rs

KI =σ02(1 + ♦s2ϕ)

√bπf(θ)

E(k),

KII =σ02s♥2ϕ

√bπk2(b/a)♦sθ

f(θ)B(k),

KIII =σ02s♥2ϕ

√bπk2(1− ν)s♥θ

f(θ)B(k),

k2 = 1− b2

a2,

f(θ) = (s♥2θ +b2

a2♦s2θ)1/4,

B(k) = (k2 − ν)E(k) + νb2

a2K(k),

r K(k) ♥ E(k) r ♣t ♥trs ♦ t rst ♥ ♥ s♦♥ ♥ rs♣t②

K(k) =

∫ π/2

0

1√

1− k2s♥2θθ,

E(k) =

∫ π/2

0

1− k2s♥2θθ.

♥ ♣rtr ♥ ϕ = 0 t s♣♠♥t ♥ t r ♥♦r♠ rt♦♥ rs

uz(x, y, 0) =2(1− ν)σ0

µ

b

E(k)

1− x2

a2− y2

b2.

r♥ ♦ t ♣t r ♥ ♣♥♥② r s tt t ♠♦ s ♥♦t ♦♥st♥t

t♦ t rt♦♥ ♦ rtr ♦♥ t r r♦♥t ♣r♦♠ s ♠♦ ②

qt♦♥ ♥ ♠s ♦♥rt♦♥ ♥ ♦♦t♦♥ s ♥♦♦s t♦ ♣♥♥②s♣ r

t♣ ♥ ♥♠r s♣t s ♦r ♣t r t ♠♥ts ♠♥t s♣t rt♦ s

s ♥♦♥♦rt♦♦♥ ss t♦rs r s♦s tt ♦r♥ ♣rs♥ts rr♦♥♦s

rst t ss ♣♦♥ts ♥ ♥r rt♦♥ ❲ t ♠♣r♦ s rs♦♥

♥ rr♦r strt♦♥

♦r t ♦♥r♥ st② rst t rst ♦ ♥♦r♠ r♥♠♥t ♥ ♣r♠tr s♣

♥ r ♥ t s♠ r ♠s ♦♥rt♦♥s ♦r ♣t r r ♥rt s

♦♥ ♦r ♣♥♥② r s ♥ r r ♦♠♣rs t rst t♥ ♥♦r♠ ♠s ♥

r ♠s ♦♥r♥ tr s ♠♦st t s♠ s tt ♦ ♣♥♥② r ♥ ♥

♦♥ tt t s♦ sts ♦r ♠♦♥ ♣t r

♦r t tst ♦ s ♦♠♣tt♦♥ ♣t t♦ ♦r♣♣ r srs ♥ t s③

Page 32: Isogeometric boundary element methods for three dimensionalorca.cf.ac.uk/102950/1/102950 - Isogeometric boundary... · 2021. 1. 20. · Isogeometric boundary element methods for three

♦r♥ ♥♣❴s eL2 ♠♣r♦ ♥♣❴s eL2

r rr♦r ♥ r ♦♣♥♥ s♣♠♥t ♦r ♣t r ♥♦t t♦rs ♥r rt♦♥ ξ❬❪ r rt♦♥ η❬❪

r ❯p = q = 2 r♣rs♥t r sr ♠ss t ♥ ♥♦r♠r♥♠♥t ♥ r rt♦♥ ♦♦ ② r r♥ ♠♥ts t s ♦s t♦r r♦♥t ♦ts r ♦♦t♦♥ ♣♦♥ts

10−1

10−2

10−1

100

h

L2

no

rm e

rro

r in

CO

D

p=2

p=3

1

0.96

1

0.98

r L2 ♥♦r♠ rr♦r ♦ ♦r ♣t r

Page 33: Isogeometric boundary element methods for three dimensionalorca.cf.ac.uk/102950/1/102950 - Isogeometric boundary... · 2021. 1. 20. · Isogeometric boundary element methods for three

102

103

10−3

10−2

10−1

100

Degrees of freedom

L2

no

rm e

rro

r in

CO

D

p=2, uniform

p=3, uniform

p=2, graded

0.58

0.58

1.28

1

1

1

r L2 ♥♦r♠ rr♦r ♦ ♦r ♣t r

L = 200a s tt ♦ ♦♠♣r t ♥♠r s t t ♥②t s♦t♦♥ ♦r

♥♥t ♦♠♥ qt♦♥s r s r ♦♠♣rs t s ♦t♥ r♦♠ M

♥tr t R = 0.02b ♥ ❱ t R = 0.02b ♦r t ♠① ♠♦ ♣t r t

♥♥t♦♥ ♥ ϕ = π/6 ♣rs♥ts t rr♦r t θ = 0 ♥ π/2 ♦r t ♥ tr

♠♦s t ♥ s♥ tt t rr♦r ♦r t s s t♥ ♥ t s ♦♥ t r

r♦♥t s s♠♦♦t ❲ ♥♦t tt t s r② ♦ ♣t r s t ♦rs t♥ ♣♥♥②

r s t♦ t r rtr ♦♥ t r r♦♥t ♥ t ① R s s t

s♥rt② t t s♠♣ ♣♦♥ts ♥r t s♠♠♦r ♥ s♠♠♥♦r ①s ♦ r♥t

t♦ ♥r② ♥ s t♦♥ ♦r st ② t♦ st♠t t s ♦r

♣t r ♦ ♦♥ ♦ t tr ♦r

KI KII KIII

❱ M ♥tr ❱ M ♥tr ❱ M ♥tr

θ = 0

θ = π/2

rr♦r ♦ s ♦r ♣t r t ϕ = π/6

t r r♦t

♥ ts st♦♥ t r sr ♣t♥ ♦rt♠ s tst ♦♠♥ t t Prs

❲ st t r r♦t ♦ t ♦r③♦♥t ♣♥♥② r ♥r t ♥♦r♠ t♥s♦♥ r♦♠

Page 34: Isogeometric boundary element methods for three dimensionalorca.cf.ac.uk/102950/1/102950 - Isogeometric boundary... · 2021. 1. 20. · Isogeometric boundary element methods for three

0 1 2 3 4 5 6−0.4

−0.3

−0.2

−0.1

0

0.1

0.2

0.3

0.4

0.5

0.6

θ (rad)

SIF

s

KI

KIII

KII

Analytical

M integral

VCCI

r trss ♥t♥st② t♦rs ♦r ♣t r t ϕ = π/6

st♦♥ t ♣r♠trs m = 2.1 ♥ t s♣ ∆amax = 0.2a ❲ ♣r♦♣t

st♣s ♥ ♠ ♦♠♣rs♦♥ t t ①t rst ♥ t rst r♦♠ t ❳

st ♠t♦ ❬❪ s ♥ r ♥ t ♥ ♦sr tt t r r♦♥t ♦r

st♣ rs t ①t s♦t♦♥ ② t r r♦♥t ts r② r♦♠

t ①t s♦t♦♥ t t r r♦t ② ❳ st ♠t♦ t♦ t t tt t

st ♠t♦ s rstrt ♥ sr♥ t r r♦♥t ①t② ♥ ts ♥r②

♠t st♣ ② st♣ ❲ t♥ ♦♠♣t t r ♣r♦♣t♦♥ ♦r m = 5 ♥ t rst

s ♣rs♥t ♥ r ❲ ♥ tt t ♥♠r r r♦♥t st rs t t

①t r♦♥t t♦ t ♥① s s♣♣♦s t♦ ①rt t rr♦r ♦ ♦ts ♦

t s♠♣ ♣♦♥ts s tst s♦s t ♣r♦♣♦s r ♣r♦♣t♦♥ s♠ ♦♥s t t② t♦

♦ t r ♥ st ♠♥♥r t♥s t♦ t s♠♦♦t♥ss ♥ t ♥♠r strss ♥ s

s♦t♦♥ ♥ ①t r♣rs♥tt♦♥ ♥ r ♦t♦♥ ♥② s♠t t r r♦t ♦r

♣t r t ♥♥t♦♥ ♥ ϕ = π/6 ♠♦ ② t qt♦♥s ♥ ♥t ♦♠♥

t♥ r♦♠ st♦♥ r strts t ♥ t ♦ t ♣r♦♣t♦♥ st♣

♦♥s♦♥s

♦r♠t♦♥ ♥ ♠♣♠♥tt♦♥ ♦ s♦♦♠tr ♦♥r② ♠♥t ♠t♦s

♦r s♠t♥ t rtr ♣r♦♠ r ♦t♥ ♥ ts ♣♣r s♠ ❯ ss

♥t♦♥s r s ♦r t srt③t♦♥ ♦ ♦♠tr②r ♥ t ♣♣r♦①♠t♦♥ ♦ s♣

Page 35: Isogeometric boundary element methods for three dimensionalorca.cf.ac.uk/102950/1/102950 - Isogeometric boundary... · 2021. 1. 20. · Isogeometric boundary element methods for three

−2 −1 0 1 2−2

−1.5

−1

−0.5

0

0.5

1

1.5

2

x

y

Exact

IGABEM

m = 2.1 ❳ m = 2.1 ♠r t

−2 −1 0 1 2−2

−1.5

−1

−0.5

0

0.5

1

1.5

2

x

y

Exact

IGABEM

m = 5

r t r r♦t ♦ t rst st♣s ♦ ♣♥♥② r

t♣ t♣ t♣

r t r r♦t s♠t♦♥ ♦ ♥ ♣t r

Page 36: Isogeometric boundary element methods for three dimensionalorca.cf.ac.uk/102950/1/102950 - Isogeometric boundary... · 2021. 1. 20. · Isogeometric boundary element methods for three

♠♥ttrt♦♥ ♥ t s♦♦♠tr r♠♦r s♥rt② strt♦♥ t♥q

♣r♦♣♦s ♥ ❬❪ ♦r t trt♠♥t ♦ ②♣rs♥r ♥trs ♥ ♠♣r♦

❬❪ s ♥ ①t♥ t♦ qrtr ♠♥t s tt t ♥ ♣♣ t♦ t♥s♦r♣r♦t

❯ ss ♥t♦♥s ♦t t ♦r♠ ♥ qt♦♥s ♦ ♥ r

③ ♦r t r ♠♦♥ ♥ t t♦ ②s t♦ ①trt s t ♦♥t♦rs M ♥tr

♥ ❱ r ♦♠♣r ♥ ♦rt♠ t♦ ♣r♦♣t t ❯r♣rs♥t r sr s

♣rs♥t ♥ t ts ♦ ts ♦r ♥

♣r♦♣♦s s♥r ♥trt♦♥ s♠ ♥ ♣rsr t qrtr r② ♦r ②

st♦rt ♠♥ts ①st ♦♠♠♦♥② ♥ s t ♥s r♦st ♠♣

♠♥tt♦♥

② st♥ t r ♠s r♥♠♥t ♥ t rt♦♥ r t r t♣ s♥rt②

rs t ♦♥r♥ rt ♥ ♠♣r♦ ② t♠s ♥ r② ♥ ♠♣r♦ ② ♦♥

♦rr t♥ t ♥♦r♠ r♥♠♥t s s♦s t ♥② ♦ ♥ t ♣♣t♦♥

♦ rtr ♣r♦♠

♦ r t♣ s②st♠ s st♣ ♥tr② ♥ ♥q② t♥s t♦ t ❯ r♣r

s♥tt♦♥ ♦ t r sr ♦♠♥♥ t t ♦♥t♥t② ♥ strss s♦t♦♥ ♥ t

♦t♥ s ♦♥ t r r♦♥t r s♠♦♦t ♥ rt

♣r♦♣♦s ♦rt♠ ♦r r ♣r♦♣t♦♥ s t t♦ st ♥ ♦r ♥①

♥ Prs t♦ t s♠♦♦t♥ss ♥ r r♦♥t ♦♠tr② ♥ ♥♠r s

tr ♦r ♦s ♦♥ t sr rs ♣r♦♠ r t r ♥trst♦♥

t t ♦② ♦♠tr② ♥ t st s♦t♦♥ s ♣r♦♣♦s ♥ ❬❪ s s♦ ♣♦♥t ♦

♥trst

♥♦♠♥ts

rst ♥ st t♦rs ♦ t♦ ♥♦ t ♥♥ s♣♣♦rt ♦ t r♠♦r

Pr♦r♠♠ ♥t r♥♥ t♦r ♥♥ ♥r r♥t ♥♠r ❵♥trt♥ ♠r

♠t♦♥ ♥ ♦♠tr s♥ ♥♦♦② P ♦rs s♦ t♥s ♣rt ♥♥

♦r s t♠ ♣r♦ ② t ❯ ♥♥r♥ ♥ P②s ♥ sr ♦♥ P

♥r r♥t P ♥ srtst♦♥ strts ♦r ❵t♦♠st ♥♥♦ s♠

t♦♥ t P ♥r r♥t P ❵♥rs t② ♦r ♥str② ♥t

Page 37: Isogeometric boundary element methods for three dimensionalorca.cf.ac.uk/102950/1/102950 - Isogeometric boundary... · 2021. 1. 20. · Isogeometric boundary element methods for three

t♦♠t r r♦t ♠t♦♥ t t ❳t♥ ♥t ♠♥t t♦ ♥ t

r♦♣♥ sr ♦♥ trt♥ ♥♣♥♥t sr r♥t t r♥t r♠♥t ♦

♥tt ❵♦rs r t♠ ♠ts s♠t♦♥ ♦ tt♥ ♥ ♥♦♥♥r ♠trs

t ♣♣t♦♥s t♦ sr s♠t♦♥ ♥ ♦♠♣tr srr② tr♦s♥♦ s

♣rt② s♣♣♦rt ② ♦♥②t r♥t ♥♠r ♥tt ❵♦♥r② ♠♥t ♠♦♥

♦ r ♣r♦♣t♦♥ ♥ ♠r♦♣♦r ♠trs

♣♣♥①

♦ ①♣♥s♦♥s ♥

♣♣♦s♥ t ♣r♠tr ♦♦r♥t ξ(ξ, η) s ♥ t ♥♦t ♥tr [ξ1, ξ2]×[η1, η2] t ♠♣♣♥

t♥ ♣r♠tr ♦♦r♥t ♥ ♣r♥t ♦♦r♥t s

ξ =1

2(ξ2 − ξ1)ξ +

1

2(ξ2 + ξ1),

η =1

2(η2 − η1)η +

1

2(η2 + η1).

♥ t ♦♥ tr♥s♦r♠t♦♥ ♦r ts ♦

Jξ =∂ξ

∂ξ=

1

2(ξ2 − ξ1),

Jη =∂η

∂η=

1

2(η2 − η1),

J(ξ) = JξJη.

②♦r ①♣♥s♦♥ ♦ xi − si t rs♣t t♦ t s♦r ♣♦♥t ♥ t ♣r♥t s♣ ♦

xi − si =[∂xi∂ξ

ξ=ξs

(ξ − ξs) +∂xi∂η

ξ=ξs

(η − ηs)]

+[∂2xi∂ξ2

ξ=ξs

(ξ − ξs)2

2

+∂2xi∂ξ∂η

ξ=ξs

(ξ − ξs)(η − ηs) +∂2xi∂η2

ξ=ξs

(η − ηs)2

2

]

+ · · ·.

Page 38: Isogeometric boundary element methods for three dimensionalorca.cf.ac.uk/102950/1/102950 - Isogeometric boundary... · 2021. 1. 20. · Isogeometric boundary element methods for three

♦t tt∂xi∂ξ

=∂xi∂ξ

∂ξ

∂ξ=∂xi∂ξ

Jξ,

∂xi∂η

=∂xi∂η

∂η

∂η=∂xi∂η

Jη,

∂2xi∂ξ2

=∂2xi∂ξ2

(∂ξ

∂ξ

)2=∂2xi∂ξ2

J2ξ ,

∂2xi∂η2

=∂2xi∂η2

(∂η

∂η

)2=∂2xi∂η2

J2η ,

∂2xi∂ξ∂η

=∂2xi∂ξ∂η

∂ξ

∂ξ

∂η

∂η=

∂2xi∂ξ∂η

JξJη

♦ t ♣♦r ♦♦r♥ts ρ(ρ, θ) ♥tr t t s♦r ♣♦♥t r ♥tr♦ ♥ t ♣r♥t s♣

s ♥ r ♣r♥t ♦♠♥ s s ♥t♦ ♦r tr♥s ♦r qrtr ♥tr②

tr♥ s rr s ♥rt sqr [−1, 1]×[−1, 1] t t♦ ♣♦♥ts ♦♥t t♦tr

♣♣♦s♥ ♣♦♥t ρ(ρ, θ) ∈ [0, ρ(θ)]×[θ1, θ2] ♥ t tr♥ ♥r ♠♣♣♥ t♥ t ♣♦r

♦♦r♥ts ♥ t sqr ♦♦r♥ts s②st♠ ξ(ξ, η) s ♣r♦r♠ s

ρ =1

2(η + 1)ρ(θ),

θ =1

2(θ2 − θ1)ξ +

1

2(θ2 + θ1).

♥ t ♦♥ tr♥s♦r♠t♦♥ ♦r ts ♦

Jρ =∂ρ

∂η=

1

2ρ(θ),

Jθ =∂θ

∂ξ=

1

2(θ2 − θ1),

J(ρ) = JρJθ.

qt♦♥ ♦♠s

xi − si = ρ[∂xi∂ξ

ξ=ξs

♦sθ +∂xi∂η

ξ=ξs

s♥θ]

+ ρ2[∂2xi∂ξ2

ξ=ξs

♦s2θ

2+∂2xi∂ξ∂η

ξ=ξs

♦sθs♥θ +∂2xi∂η2

ξ=ξs

s♥2θ

2

]

+O(ρ3)

: = ρAi(θ) + ρ2Bi(θ) +O(ρ3).

Page 39: Isogeometric boundary element methods for three dimensionalorca.cf.ac.uk/102950/1/102950 - Isogeometric boundary... · 2021. 1. 20. · Isogeometric boundary element methods for three

♥ ♥

A :=

(

3∑

k=1

[Ak(θ)]2

)

1

2

,

C :=3∑

k=1

Ak(θ)Bk(θ).

rts ♦ r = |x− s| r

r,i =xi − sir

=Ai

A+

(

Bi

A−Ai

C

A3

)

ρ+O(ρ2)

:= di0 + di1ρ+O(ρ2).

tr♠ 1/r3 s1

r3=

1

A3ρ3− 3C

A5ρ2+O(

1

ρ)

:=S−2

ρ3+S−1

ρ2+O(

1

ρ).

❯ ss ♥t♦♥ s s♦ ①♣♥ s

Na(ξ) = Na(ξs) + ρ[∂Na

∂ξ

ξ=ξs

Jξ♦sθ +∂Na

∂η

ξ=ξs

Jηs♥θ]

+O(ρ2)

:= Na0 +Na1(θ)ρ+O(ρ2).

♦r t sr ♣♦♥t ξ(ξ, η) ♥ t ♥♦t ♥tr [ξ1, ξ2] × [η1, η2] ♥ t♦ t♥♥t

t♦rs ♦♥ t ξ ♥ η rt♦♥s rs♣t② s

m1 =[∂x

∂ξ,∂y

∂ξ,∂z

∂ξ

]

,

m2 =[∂x

∂η,∂y

∂η,∂z

∂η

]

.

♥ ♥ t t ♥♦r♠ t♦rs tr♦

n = m1 ×m2 =[∂y

∂ξ

∂z

∂η− ∂z

∂ξ

∂y

∂η,∂z

∂ξ

∂x

∂η− ∂x

∂ξ

∂z

∂η,∂x

∂ξ

∂y

∂η− ∂y

∂ξ

∂x

∂η

]

.

♦♥ ♦r tr♥s♦r♠t♦♥ r♦♠ ♣r♠tr s♣ t♦ ♣②s s♣ s t ♥t ♦ t

Page 40: Isogeometric boundary element methods for three dimensionalorca.cf.ac.uk/102950/1/102950 - Isogeometric boundary... · 2021. 1. 20. · Isogeometric boundary element methods for three

♥♦r♠ t♦r n

J(ξ) =[(∂y

∂ξ

∂z

∂η− ∂z

∂ξ

∂y

∂η

)2+(∂z

∂ξ

∂x

∂η− ∂x

∂ξ

∂z

∂η

)2+(∂x

∂ξ

∂y

∂η− ∂y

∂ξ

∂x

∂η

)2]1/2

: =[

3∑

k=1

J2k (ξ)

]1/2

♥t ♥♦r♠ t♦r n ♦ ①♣rss s

n(ξ) =n

J(ξ).

♦♠♣♦♥♥t Ji(ξ) ♥ ①♣♥ t t s♦r ♣♦♥t ♦r ♥st♥

J1(ξ) = J1(ξs) + ρ[∂J1∂ξ

ξ=ξs

Jξ♦sθ +∂J1∂η

ξ=ξs

Jηs♥θ]

+O(ρ2)

: = J10 + J11(θ)ρ+O(ρ2),

∂J1∂ξ

=∂

∂ξ

(∂y

∂ξ

∂z

∂η− ∂z

∂ξ

∂y

∂η

)

.

♦ ♥ ♦t♥ Ji(ξ) s

Ji(ξ) = Ji0 + Ji1(θ)ρ+O(ρ2).

♦♠♥♥ t qt♦♥ rr t

ni(ξ) =1

J(ξ)[Ji0 + Ji1(θ)ρ+O(ρ2)].

♦ t tr♠s r ♣r♣r ♦r t ①♣♥s♦♥ ♦ t ♥tr♥ ts t s♠♣ ①♠♣

I = =

S

r,ini(ξ)Na(ξ)

r3S.

tr srt③t♦♥

I =

∫ 2π

0

∫ ρ(θ)

0

r,iniNa

r3J(ξ)J(ξ)ρρθ,

r J(ξ) s r♦♠ ♣r♥t t♦ ♣r♠tr s♣ ♥ ♥ qt♦♥ J(ξ) r♦♠ ♣r♠tr

t♦ ♣②s s♣ ♥ ♥ qt♦♥ ρ(θ) s t ♣♣r ♦♥ ♦ ρ ♥ ♥ s♥ ♥

r

Page 41: Isogeometric boundary element methods for three dimensionalorca.cf.ac.uk/102950/1/102950 - Isogeometric boundary... · 2021. 1. 20. · Isogeometric boundary element methods for three

♥ ssttt qt♦♥s ♥t♦ t srt③t♦♥

I =

∫ 2π

0

∫ ρ(θ)

0

[

di0 + di1ρ+O(ρ2)] 1

J(ξ)

[

Ji0 + Ji1ρ+O(ρ2)][

Na0 +Na1ρ+O(ρ2)]

[S−2

ρ3+S−1

ρ2+O(

1

ρ)]

J(ξ)J(ξ)ρρθ

=

∫ 2π

0

∫ ρ(θ)

0

[

di0Ji0Na0 + (di1Ji0Na0 + di0Ji1Na0 + di0Ji0Na1)ρ+O(ρ2)]

[S−2

ρ2+S−1

ρ+O(1)

] 1

ρJ(ξ)J(ξ)J(ξ)ρρθ

=

∫ 2π

0

∫ ρ(θ)

0

(I−2

ρ2+I−1

ρ+O(1)

)

J(ξ)ρθ,

r I−2 I−1 r ♦♥② ♥t♦♥s ♦ θ

I−2 = S−2di0Ji0Na0,

I−1 = S−1di0Ji0Na0 + S−2(di1Ji0Na0 + di0Ji1Na0 + di0Ji0Na1).

trt♥ t ①♣t s♥r ♣rt ♥ t ♦r♥ ♥tr♥ ♥ qt♦♥ t rr

♥tr ♦t♥

Ir =

∫ 2π

0

∫ ρ(θ)

0

[r,iniNa

r3J(ξ)ρ− I−2

ρ2− I−1

ρ

]

J(ξ)ρθ,

s ♦ ♥tr ♥ t s♥ ♥♦r♠ ss♥ r ♥ t ①♣t ♣rt t♥

♥ trt ♥ s♠♥②t ② ♦r t s♦r ♣♦♥t ♦t ♥ t

s♥r ♠♥t s♠ r s rt t♦ ① t s♦r ♣♦♥t rs ε ♥ ♣②s

s♣ ❲♥ ♠♣♣♥ t r ♥t♦ t ♥tr♥s ♣♦r ♦♦r♥t t r st♦rt

♥r② ♣♦r ♦♦r♥t ρ s r♣rs♥t t rs♣t t♦ ε s

ρ := α(ε, θ) = εβ(θ) + ε2γ(θ) +O(ε3).

♦ t t ♦♥ts β ♥ γ t rs ♦ t r s ♥ s t ②♦r ①♣♥s♦♥ ♥

♥tr♥s ♣♦r ♦♦r♥ts s

ε = ρA(θ) + ρ2C(θ)

A(θ)+O(ρ3).

Page 42: Isogeometric boundary element methods for three dimensionalorca.cf.ac.uk/102950/1/102950 - Isogeometric boundary... · 2021. 1. 20. · Isogeometric boundary element methods for three

rrs♦♥ ♦ ts srs s

ρ = α(ε, θ) = ε1

A− ε2

C

A4+O(ε3).

s t

β =1

A,

γ = − C

A4,

r ♦♥② ♥t♦♥s ♦ θ ♥ ts rst ♦♦ t t ①♣t str♦♥ s♥r ♣rt ♥ ♥

t ♠t ♦r♠ s

limε→0

∫ 2π

0

∫ ρ(θ)

α(ε,θ)

I−1(θ)

ρJ(ξ)ρθ

= limε→0

∫ 2π

0

∫ ρ(θ)

α(ε,θ)

I−1(θ)

ρJ(ξ)J(ρ)ηξ

= limε→0

∫ 2π

0I−1(θ)J(ξ)Jθ

[

∫ ρ(θ)

α(ε,θ)

1

ρJρη

]

ξ

= limε→0

∫ 2π

0I−1(θ)J(ξ)Jθ

[

∫ ρ(θ)

α(ε,θ)

1

ρρ]

ξ

= limε→0

∫ 2π

0I−1(θ)J(ξ)Jθ[♥ρ(θ)− ♥α(ε, θ)]ξ

=

∫ 2π

0I−1(θ)J(ξ)♥ρ(θ)Jθξ − lim

ε→0

∫ 2π

0I−1(θ)J(ξ)♥α(ε, θ)Jθξ

=

∫ 2π

0I−1(θ)J(ξ)♥ρ(θ)Jθξ − lim

ε→0

∫ 2π

0I−1(θ)J(ξ)♥εβ(θ)Jθξ

=

∫ 2π

0I−1(θ)J(ξ)♥

ρ(θ)

β(θ)Jθξ − J(ξ)♥ε lim

ε→0

∫ 2π

0I−1(θ)θ

=

∫ 2π

0I−1(θ)J(ξ)♥

ρ(θ)

β(θ)Jθξ,

r J(ρ) s r♦♠ ♣♦r t♦ sqr ♦♦r♥ts ♥ ♥ qt♦♥ ♦t tt t st

tr♠ s ♥ s♥∫ 2π

0I−1(θ)θ = 0.

tr ♥trt♥ t s♥r tr♠ t rs♣t t♦ ρ ♥②t② ♥ t t s ♦ qt♦♥s

t ①♣t str♦♥ s♥r ♥tr♥ s tr♥srr s rr ♦♥♠♥s♦♥ ♥

tr ♥ ♥♦r♠ ss♥ r t♥ ♥ ♣♣ ♠r trt♠♥t ♣♣s t♦ t ①♣t

Page 43: Isogeometric boundary element methods for three dimensionalorca.cf.ac.uk/102950/1/102950 - Isogeometric boundary... · 2021. 1. 20. · Isogeometric boundary element methods for three

②♣rs♥r tr♠ t♦♥ ♦r qt♦♥ s ♦t♥

I = Ir +

∫ 2π

0I−1(θ)J(ξ)♥

ρ(θ)

β(θ)Jθξ −

∫ 2π

0I−2(θ)J(ξ)

[ γ(θ)

β2(θ)+

1

ρ(θ)

]

Jθξ

①r② s♣♠♥t ♥ strss s ♥ M ♥tr

①r② strss σ(2)ij ♥ s♣♠♥t u

(2)j r ♥ s

σxx =K

(2)I√2πr

♦sθ

2

(

1− s♥θ

2s♥

2

)

− K(2)II√2πr

s♥θ

2

(

2 + ♦sθ

2♦s

2

)

σyy =K

(2)I√2πr

♦sθ

2

(

1 + s♥θ

2s♥

2

)

+K

(2)II√2πr

s♥θ

2♦s

θ

2♦s

2,

τxy =K

(2)I√2πr

s♥θ

2♦s

θ

2♦s

2+

K(2)II√2πr

♦sθ

2

(

1− s♥θ

2s♥

2

)

,

τyz =K

(2)III√2πr

♦sθ

2,

τzx = − K(2)III√2πr

s♥θ

2,

τzz = ν(σxx + σyy),

ux =KI

r

2π♦s

θ

2

(

κ− 1 + 2s♥2θ

2

)

+(1 + ν)KII

E

r

2πs♥

θ

2

(

κ+ 1 + 2♦s2θ

2

)

,

uy =KI

r

2πs♥

θ

2

(

κ+ 1− 2♦s2θ

2

)

+(1 + ν)KII

E

r

2π♦s

θ

2

(

1− κ+ 2s♥2θ

2

)

,

uz =2KIII

µ

r

2πs♥

θ

2.

r (r, θ) r t r t♣ ♣♦r ♦♦r♥ts ♥ µ = E2(1+ν) κ = 3− 4ν

①r② str♥ ♥ ♦t♥ ② r♥tt♥ uj t rs♣t t♦ t ♣②s

♦♦r♥t

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r♥s

❬❪ rt P ❲r③②♥ ♥ ♥r rtrr② r r♣rs♥tt♦♥ s♥

s♦ ♠♦♥ ♥♥r♥ t ♦♠♣trs

❬❪ ❱ rtt♥ ❱ ♦♦ ♥ ② ♥ r♠s♥ t♥qs ♦r ♦♠♣①

r ♣r♦♣t♦♥ ♥

❬❪ ♦ ♥ ♦s♠ ♥ ③ r r♦t ♠♦♥ t♦

♠t ♣t ♠s r♥♠♥t s ♦♥ ♠♦P t♥q ♣♣ t♠t

♦♥

❬❪ ö♠♥♥ ♥ ♥ r ♦♣♠♥t ♦ ♥ s♦tr ♦r ♣t

r r♦t s♠t♦♥s ♥ strtrs ♥♥r♥ rtr ♥s

♥r②

❬❪ ♥♦ rt♥♠ ♥ ♥ ❲♠s tr♠♥s♦♥

♥♠r st② ♦ t r r♦t s♥ r♠s♥ t♥qs ♥♥r♥ rtr

♥s

❬❪ r♥♦ ❱ ♥t♥s ♥ ♦st r ♦♥ ♣t r♠s♥ t♥qs

♦r r r♦t ♠♦♥ ♥♥r♥ rtr ♥s ♥

❬❪ ♦ës ♦♦ ♥ ②ts♦ ♥t ♠♥t ♠t♦ ♦r r r♦t t♦t

r♠s♥ ♥tr♥t♦♥ ♦r♥ ♦r ♠r t♦s ♥ ♥♥r♥

❬❪ ♠r ♦ës ♦r♥ ♥ ②ts♦ ①t♥ ♥t ♠♥t ♠t♦

♦r tr♠♥s♦♥ r ♠♦♥ ♥tr♥t♦♥ ♦r♥ ♦r ♠r t♦s ♥

♥♥r♥

❬❪ ♠r ♦♣♣ ét ♥ ♦ës r♠♥s♦♥ ♥♦♥♣♥r r

r♦t ② ♦♣ ①t♥ ♥t ♠♥t ♥ st ♠r♥ ♠t♦ ♥tr♥t♦♥

♦r♥ ♦r ♠r t♦s ♥ ♥♥r♥

❬❪ r♦ ♦ës ♥ ②ts♦ ♦♥♣♥r r r♦t ② t ①t♥

♥t ♠♥t ♥ stsPrt st ♣t ♥tr♥t♦♥ ♦r♥ ♦r ♠r

t♦s ♥ ♥♥r♥

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❬❪ ♦ës r♦ ♥ ②ts♦ ♦♥♣♥r r r♦t ② t ①t♥ ♥t

♠♥t ♥ stsPrt ♥ ♠♦ ♥tr♥t♦♥ ♦r♥ ♦r ♠r

t♦s ♥ ♥♥r♥

❬❪ t♦s t③ P ♦rs ♥ ss ♦♥t♦♥ ♥ ♦♣t♠②

♦♥r♥t ❳ ♦r ♥r st rtr ♥tr♥t♦♥ ♦r♥ ♦r ♠r

t♦s ♥ ♥♥r♥ ♣s ♥♥

❬❪ ♦rs ♥ ♦r♥ ♥r ♥t ♠♥ts ♥ sts ♦r ♠ t♦r♥ s

sss♠♥t ♦ ♦♠♣① strtrs ♥♥r♥ rtr ♥s

❬❪ P ♦rs ♥ ♦t rt r♦r② ♥ ♣♦str♦r rr♦r st♠t ♦r ①

t♥ ♥t ♠♥ts ♦♠♣tr t♦s ♥ ♣♣ ♥s ♥ ♥♥r♥

❬❪ ❲②rt ♦t ♦♦♥ P rt♥② Pr♦♥ ♠ ♥ ♥

strtr♥ ❳ ♣♣r♦s ♣♣ t♦ tr♠♥s♦♥ r ♣r♦♣t♦♥ ♦r♥

♦ ♦♠♣tt♦♥ ♥ ♣♣ t♠ts

❬❪ P r②s ♥ ②ts♦ ♠♥t r r♥ ♠t♦ ♦r ②♥♠ ♣r♦♣t♦♥

♦ rtrr② rs ♥tr♥t♦♥ ♦r♥ ♦r ♠r t♦s ♥ ♥♥r♥

❬❪ ❱♥tr ❳ ❳ ♥ ②ts♦ t♦r st ♠t♦ ♥ ♥ s♦♥t♥t②

♣♣r♦①♠t♦♥s ♦r r r♦t ② ♥tr♥t♦♥ ♦r♥ ♦r ♠r t♦s

♥ ♥♥r♥

❬❪ ③ ♦rs ♥ ❩ ♥ tr♠♥s♦♥ ♠♦♥ ♦ r r♦t s♥

♣rtt♦♥ ♦ ♥t② ♠t♦s ♦♠♣trs trtrs ♠r

❬❪ P ♦rs ③ ♥ ❩ r♠♥s♦♥ r ♥tt♦♥ ♣r♦♣t♦♥

r♥♥ ♥ ♥t♦♥ ♥ ♥♦♥♥r ♠trs ② ♥ ①t♥ ♠sr ♠t♦ t♦t

s②♠♣t♦t ♥r♠♥t ♥♥r♥ rtr ♥s

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❬❪ ❱ P ②♥ ③ ♦rs ♥ ♦t sss ♠t♦s r ♥

♦♠♣tr ♠♣♠♥tt♦♥ s♣ts t♠ts ♥ ♦♠♣trs ♥ ♠t♦♥

❬❪ ♦♥ ♥ ♥ rt♦♥s ♦ ♥tr qt♦♥s ♦ stt② ♦r♥ ♦ ♥♥r

♥ ♥s

❬❪ ♥ ♥ ♦♥ ♦ ♦♥r② ♠♥t ♠t♦s t ♠♣ss ♦♥

②♣rs♥r ♥trs ♥ r♥t srs ♣♣

❬❪ P♦rt ♥ P ♦♦ ♦♥r② ♠♥t ♠t♦

t ♠♣♠♥tt♦♥ ♦r r ♣r♦♠s ♥tr♥t♦♥ ♦r♥ ♦r ♠r t♦s ♥

♥♥r♥

❬❪ ❨ ♥ ♦♥r② ♠♥t ♠t♦ ♦r tr♠♥s♦♥ rtr

♠♥s ♥②ss ♥♥r♥ ♥②ss t ♦♥r② ♠♥ts

❬❪ P s♥♦ ♥ ♦♥r② ♠♥t ssss♠♥t ♦ tr♠♥s♦♥

t r r♦t ♥♥r♥ ♥②ss t ♦♥r② ♠♥ts

❬❪ P s♥♦ ♥ r♠♥s♦♥ ♦♥r② ♠♥t ♥②ss ♦ t

r r♦t ♥ ♥r ♥ ♥♦♥♥r rtr ♣r♦♠s ♥♥r♥ rtr ♥s

st

❬❪ ❱ tã♦ ♥ P ♦♦ ♦♥r② ♠♥t ♦r♠t♦♥ ♦r

st♦♣st rtr ♠♥s ♥tr♥t♦♥ ♦r♥ ♦r ♠r t♦s ♥ ♥

♥r♥

❬❪ P ♥s ♥ P ♦♦ ♦♥r② ♠♥t ♠t♦ ♥

②♥♠ rtr ♠♥s ♥♥r♥ ♥②ss t ♦♥r② ♠♥ts

♥r②

❬❪ ♥s ♥ ❲ ②♥♠ t♦♠t t r r♦t ♥

Prssr ❱sss ♥ P♣♥ ♦♥r♥ ♣s ♠r♥ ♦t② ♦ ♥

♥♥rs

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❬❪ rtr P ❲r③②♥ ♥ ♥r t♦♠t r r♦t s♠t♦♥

♥tr♥t♦♥ ♦r♥ ♦r ♥♠r ♠t♦s ♥ ♥♥r♥

❬❪ r ♥ ❳♦ ②♠♠tr ♦r♠ ♥tr qt♦♥ ♠t♦ ♦r tr

♠♥s♦♥ rtr ♥②ss ♦♠♣tr t♦s ♥ ♣♣ ♥s ♥ ♥♥r♥

❬❪ r♥ rtr ♣r♦♣t♦♥ ♥ ② t s②♠♠tr r♥ ♦♥r② ♠♥t

♠t♦ ♥tr♥t♦♥ ♦r♥ ♦ rtr

❬❪ r♥ ♦t ♣r♥tt ♥ ♦③③ rtr ♥②ss ② t s②♠♠tr

r♥ ♦♠♣tt♦♥ ♥s

❬❪ P s♦ Pr ♥ tr tr♥t♥ ♠t♦ ♦r ♥②③♥

♥♦♥♣♥r rs ♥ tr r♦t ♥ strtr ♦♠♣♦♥♥ts ♦♠♣tr ♦♥ ♥

♥♥r♥ ♥s

❬❪ r♥ ♥ ♦t ♦♣♥ ♦r rtr ♠♥s ♣♣t♦♥s

♦♠♣tt♦♥ ♥s

❬❪ s ♦ttr ♥ ❨ ③s s♦♦♠tr ♥②ss ♥t ♠♥ts

❯ ①t ♦♠tr② ♥ ♠s r♥♠♥t ♦♠♣tr t♦s ♥ ♣♣ ♥s

♥ ♥♥r♥

❬❪ ♦tt ♠♣s♦♥ ♥s ♣t♦♥ P ♦rs s ♥

❲ rr s♦♦♠tr ♦♥r② ♠♥t ♥②ss s♥ ♥strtr s♣♥s

♦♠♣tr t♦s ♥ ♣♣ ♥s ♥ ♥♥r♥

❬❪ ♠♣s♦♥ P ♦rs r②♥ ♥ ③ t♦♠♥s♦♥ s♦♦

♠tr ♦♥r② ♠♥t t♦ ♦r st♦stt ♥②ss ♦♠♣tr t♦s ♥ ♣♣

♥s ♥ ♥♥r♥

❬❪ ♠♣s♦♥ ♦tt s ♦♠s ♥ ♥ ♦st s♦♦♠tr

♦♥r② ♠♥t ♥②ss ♦♠♣tr t♦s ♥ ♣♣ ♥s ♥ ♥♥r♥

♣ ♣t

❬❪ ❩♥ ♥ s♦♦♠tr ♥②ss ♥ ♦r ♣♦t♥t ♣r♦♠

♥♥r♥ ♥②ss t ♦♥r② ♠♥ts

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❬❪ ♥ ❳ ♥ s♦♦♠tr ♥②ss ♥ s♣ ♦♣t♠③t♦♥ ♦♥r② ♥tr

♦♠♣tr s♥

❬❪ P♦ts ♥♥s P s sss ♥ rr ♥ s♦♦♠tr ♦r

①tr♦r ♣♦t♥t♦ ♣r♦♠s ♥ t ♣♥ ♥ ♦♥t ♦♥r♥ ♦♥

♦♠tr ♥ P②s ♦♥ P ♣s ❨♦r ❨ ❯

❬❪ ♥♥s ❱ ♦sts P♦ts P s sss P r♦stts

♦tt ♥ s s♦♦♠tr ♦♥r②♠♥t ♥②ss ♦r t

rsst♥ ♣r♦♠ s♥ s♣♥s ♦♠♣tr t♦s ♥ ♣♣ ♥s ♥ ♥

♥r♥ ♣t♠r

❬❪ ❱ ♦sts ♥♥s P♦ts ♥ P s ♣ s♣ ♦♣t♠③t♦♥ t

s♣♥ s s♦♦♠tr s♦r ♦♠♣tr t♦s ♥ ♣♣ ♥s ♥

♥♥r♥ rr②

❬❪ P r②♥ ♥ ♦ts ①t♥ s♦♦♠tr ♦♥r② ♠♥t ♠t♦

❳ ♦r t♦♠♥s♦♥ ♠♦t③ ♣r♦♠s ♦♠♣tr t♦s ♥ ♣♣

♥s ♥ ♥♥r♥

❬❪ P r②♥ ♥ ♦ts ①t♥ s♦♦♠tr ♦♥r② ♠♥t

♠t♦ ❳ ♦r tr♠♥s♦♥ ♠♠ ♦st sttr♥ ♣r♦♠s ♦♠

♣tr t♦s ♥ ♣♣ ♥s ♥ ♥♥r♥ rr②

❬❪ r rss ❩♥r ♥sr ♥ P rs ♦♥r② ♠♥t ♥②ss

t tr♠♠ ❯ ♥ ♥r③ ♣♣r♦ r①♦r

❬❪ ❨ ❲♥ ♥s♦♥ ♥ P ② ♠t♣t ♥♦♥s♥r s♦♦♠tr ♦♥r②

♠♥t ♠t♦ s♥ tr♠♠ ♠♥ts ♦♠♣tt♦♥ ♥s

❬❪ rss ❩♥r r ♥ P rs st s♦♦♠tr ♦♥r② ♠♥t

♠t♦ s ♦♥ ♥♣♥♥t ♣♣r♦①♠t♦♥ ♦♠♣tr t♦s ♥ ♣♣

♥s ♥ ♥♥r♥

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❬❪ s ♥t♥r ♥ Prt♦rs ♥ ♥t ♣♦str♦r rr♦r st♠

t♦♥ ♦r ♣t ④⑥ ♦♥r② ♠♥t ♠t♦s ♦r ②s♥r ♥tr qt♦♥s

♦♠♣tr t♦s ♥ ♣♣ ♥s ♥ ♥♥r♥

❬❪ ♠ ♥t ♠♣♦ ♥ st♥ s♦♠tr ♥②ss ♥ s②♠♠tr

r♥ ♥♠r st② ♣♣ t♠ts ♥ ♦♠♣tt♦♥ ♣s

❬❪ s ♦♥ ♥ s s♦♦♠tr ♥②ss ♦ ♦♥r② ♥tr

qt♦♥s r♣♦rt

❬❪ ②r ♥s♦♥ ②ts♦ ❨ ③s ♥ s ❳ ♥ s♦♦♠t

r ♥②ss ♦r ♥r rtr ♠♥s ♥tr♥t♦♥ ♦r♥ ♦r ♠r t♦s

♥ ♥♥r♥

❬❪ ♦rs ❱③ ♥ ♦♠♠ ①t♥ s♦♦♠tr ♥②ss ♦r s♠

t♦♥ ♦ stt♦♥r② ♥ ♣r♦♣t♥ rs ♥tr♥t♦♥ ♦r♥ ♦r ♠r t♦s

♥ ♥♥r♥

❬❪ ❱ P ②♥ ♥ts P ♦rs ♥ ③ s♦♦♠tr ♥②ss ♥

♦r ♥ ♦♠♣tr ♠♣♠♥tt♦♥ s♣ts t♠ts ♥ ♦♠♣trs ♥ ♠

t♦♥ ♥

❬❪ ②♥♥ ❱③ ②♥ ②♥❳♥ ❳ ❩♥ P rs

❩ ❨ ③s ♦r♥③s ♥ ③ ♥ ①t♥ s♦♦♠tr t♥ s

♥②ss s ♦♥ r♦♦ t♦r② ♦♠♣tr t♦s ♥ ♣♣ ♥s ♥

♥♥r♥ rr②

❬❪ ❱ ❱r♦♦s ♦tt ♦rst ♥ s ♥ s♦♦♠tr ♣♣r♦

t♦ ♦s ③♦♥ ♠♦♥ ♥tr♥t♦♥ ♦r♥ ♦r ♠r t♦s ♥ ♥♥r♥

❬❪ ❱ P ②♥ P rr♥ ♥ P ♦rs ♦ ♥ tr♠♥s♦♥ s♦♦♠tr

♦s ♠♥ts ♦r ♦♠♣♦st ♠♥t♦♥ ♥②ss ♦♠♣♦sts Prt ♥♥r♥

♣r

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❬❪ ♦ ♥ ♦ s♦♦♠tr s♣ s♥ s♥stt② ♥②ss ♦ strss ♥t♥st②

t♦rs ♦r r r ♣r♦♠s ♦♠♣tr t♦s ♥ ♣♣ ♥s ♥ ♥♥r♥

♣t♠r

❬❪ ♠t ♥ r②♥ s♦♦♠tr ♥r ♣♣r♦①♠t♦♥s ♦♠♣tr

t♦s ♥ ♣♣ ♥s ♥ ♥♥r♥ t♦r

❬❪ ❯♣rt ♦♥ ♠t ♥ r②♥ r st♥ st♠t♦♥s ♦r

♥r s♦♦♠tr ♥②ss ♦♠♣tr t♦s ♥ ♣♣ ♥s ♥ ♥♥r♥

t♦r

❬❪ ❲ ♦♥ ♥ ♥ ♠ ♣♣♥ t♥qs ♦r s♦♦♠tr ♥②ss ♦

♣t ♦♥r② ♣r♦♠s ♦♥t♥♥ s♥rts ♦♠♣tr t♦s ♥ ♣♣

♥s ♥ ♥♥r♥ rr②

❬❪ ♠ ♥ ❲ ♦♥ ♥r s♦♦♠tr ♥②ss ♦ ♣t ♦♥r②

♣r♦♠s ♥ ♦♠♥s t rs ♥♦r ♦r♥rs ♥tr♥t♦♥ ♦r♥ ♦r ♠r

t♦s ♥ ♥♥r♥ ♥r②

❬❪ tr♥ ❲♥ ♦♥ ♥ r s♦♦♠tr ♥②ss ♥♥ ② t s

♦♥r② ♥t ♠♥t ♠t♦ ♦♠♣tr t♦s ♥ ♣♣ ♥s ♥ ♥♥r

♥ ♥r②

❬❪ ♥ ♦r♠t♦♥ ♥ ♥♠r trt♠♥t ♦ ♦♥r② ♥tr qt♦♥s t

②♣rs♥r r♥s ♥r ♥trs ♥ ♦♥r② ♠♥t ♠t♦s ♣s

❬❪ P ♥ ❲ r ❯ ♦♦ s♣r♥r

❬❪ ❨ ♥ ♦♣ ♦♠ ♥tts ♦r ♥♠♥t s♦t♦♥s ♥ tr ♣♣t♦♥s

t♦ ②s♥r ♦♥r② ♠♥t ♦r♠t♦♥s ♥♥r♥ ♥②ss t ♦♥r②

♠♥ts

❬❪ ❨ ❲♥ ♥ ♥s♦♥ t♣t ♥♦♥s♥r s♦♦♠tr ♦♥r② ♠♥t

♥②ss ♥ ♦♠♣tr t♦s ♥ ♣♣ ♥s ♥ ♥♥r♥

st

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❬❪ ♥ rs♥s♠② ♦♣ ♥ ③③♦ ♥r ♦rt♠ ♦r t

♠r ♦t♦♥ ♦ ②♣rs♥r ♦♥r② ♥tr qt♦♥s ♦r♥ ♦ ♣♣

♥s

❬❪ ♦♥ ❲♥ ♥ ❳♦ ♥② ♠♣r♦♠♥t ♦ t ♣♦r ♦♦r♥t tr♥s♦r♠t♦♥

♦r t♥ s♥r ♥trs ♦♥ r ♠♥ts ♥♥r♥ ♥②ss ❲t

♦♥r② ♠♥ts

❬❪ sr ♥ st ♠t♦s ♥ ②♥♠ ♠♣t srs ♦♠

♣r♥r ♥ s♥ss

❬❪ ♦ës ♦r P rtr ♥ ♠ ♦♠♣tt♦♥ ♣♣r♦ t♦ ♥

♦♠♣① ♠r♦strtr ♦♠trs ♦♠♣tr t♦s ♥ ♣♣ ♥s ♥

♥♥r♥ ②

❬❪ rt ♥ t♥ ♠r ♠s ♦r t ♠t♦♥♦ ♥ t

qt♦♥s ♦♥ r♥t ♦♠♥s ♦r♥ ♦ ♦♠♣tt♦♥ P②ss

♣t♠r

❬❪ ♦♣♣ ♥ ♠r t r ♣r♦♣t♦♥ ♦ ♠t♣ ♦♣♥r rs

t t ♦♣ ①t♥ ♥t ♠♥tst ♠r♥ ♠t♦ ♥tr♥t♦♥ ♦r♥ ♦

♥♥r♥ ♥ ②

❬❪ P rs ♥ ②♦♥ r ♣r♦♣t♦♥ t t ①t♥ ♥t ♠♥t ♠t♦

♥ ②r ①♣t♠♣t r sr♣t♦♥ ♥tr♥t♦♥ ♦r♥ ♦r ♠r

t♦s ♥ ♥♥r♥

❬❪ Ps③♥② ♥ ❲ ❩♠♠r♠♥ ♠r s♠t♦♥ ♦ ♠t♣ rtr ♣r♦♣

t♦♥ s♥ rtrr② ♠ss ♦♠♣tr t♦s ♥ ♣♣ ♥s ♥ ♥♥r♥

rr②

❬❪ r③♦♥ P r rt ♥❲ ttr ♠♣r♦♠♥ts ♦ ①♣t r sr

r♣rs♥tt♦♥ ♥ ♣t t♥ t ♥r③ ♥t ♠♥t ♠t♦ t ♣♣t♦♥

t♦ tr♠♥s♦♥ r ♦s♥ ♥tr♥t♦♥ ♦r♥ ♦r ♠r t♦s ♥

♥♥r♥

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❬❪ Ps③♥② ♥ ❲ ❩♠♠r♠♥ ♠r rtr r♦t ♠♦♥ s♥ s♠♦♦t

sr ♦♠tr ♦r♠t♦♥ ♥♥r♥ rtr ♥s

❬❪ r ♥ ♥ ♦ ♦r♠t♦♥ ♦ ❯ rs t♠t

♠t♦s ♦r rs ♥ srs r♦♠s♦ ♣s

❬❪ ♥ ♥ ❲ ❲s♦♥ ♥ t ♥t ♠♥t ♠t♦ ♥ ♥r rtr

♠♥s ♥♥r♥ rtr ♥s ②

❬❪ ♥ ♥ t ♠t♦ ♦ rt r ①t♥s♦♥s ♥tr♥t♦♥ ♦r♥ ♦r ♥♠r

♠t♦s ♥ ♥♥r♥

❬❪ ♥ P ❲r③②♥ ♥ ♥r ♥ t rt r ①t♥s♦♥ ♠t♦

♦r t♥ t rts ♦ ♥r② rs rts ♦r ♣♥r r ♦ rtrr②

s♣ ♥r ♠♦ ♦♥ ♥♥r♥ rtr ♥s ②

❬❪ s P ❲r③②♥ ♥ ♥r s♠t♦♥ ♦ rtrr② r

r♦t s♥ ♥ ♥r②s ♦r♠t♦♥ Prt P♥r r♦t ♥♥r♥ rtr

♥s

❬❪ s P ❲r③②♥ ♥ ♥r ♠t♦♥ ♦ rtrr② ①♦

r r♦t ❯s♥ ♥ ♥r②s ♣♣r♦ ♥ ② rr♦ ♥ ♠♥t ②

t♦rs rtr t r ♥ ♠ ♦t♦♥ ❱♦♠ ♦♥r♥ Pr♦

♥s ♦ t ♦t② ♦r ①♣r♠♥t ♥s rs ♣s ♣r♥r ♥tr♥t♦♥

Ps♥

❬❪ t P ♦rs P rr♥ ♥ rt♠② ♦ ♥r② ♥♠③t♦♥

♦r tr r♦t ♥ ♥r st rtr s♥ t ①t♥ ♥t ♠♥t

t♦s t ❲♦r ♦♥rss ♦♥ ♦♠♣tt♦♥ ♥s ❲ ❳ r♦♥

❬❪ rr ❱rt r ♦sr t♥q st♦r② ♣♣r♦ ♥ ♣♣t♦♥s ♣♣

♥s s

❬❪ ♣t ♥♣♥♥t ♥tr ♥ t ♣♣r♦①♠t ♥②ss ♦ str♥ ♦♥♥tr

t♦♥ ② ♥♦ts ♥ rs ♦r♥ ♦ ♣♣ ♠♥s

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❬❪ tr♥ r ♥ ♥♠ ♦♥t♦r ♥tr ♦♠♣tt♦♥ ♦ ♠①♠♦

strss ♥t♥st② t♦rs ♥tr♥t♦♥ ♦r♥ ♦ rtr

❬❪ ❨ ❲♥ ♥ ♦rt♥ ♠①♠♦ r ♥②ss ♦ s♦tr♦♣ s♦s

s♥ ♦♥srt♦♥ s ♦ stt② ♦r♥ ♦ ♣♣ ♥s

❬❪ P ❲♥ ♥ P ♦♦ ♦♥t♦r ♥tr ♦r t t♦♥ ♦ strss

♥t♥st② t♦rs ♣♣ ♠t♠t ♠♦♥

❬❪ ♥ r ♣♦st♣r♦ss♥ ♣♣r♦ ♥ t ♥t ♠♥t ♠t♦ Prt

t♦♥ ♦ strss ♥t♥st② t♦rs ♥tr♥t♦♥ ♦r♥ ♦r ♥♠r ♠t♦s

♥ ♥♥r♥

❬❪ P Prr ♥ rt ①trt♦♥ ♦ strss ♥t♥st② t♦rs r♦♠ ♥r③ ♥t

♠♥t s♦t♦♥s ♥♥r♥ ♥②ss t ♦♥r② ♠♥ts ♣r

❬❪ ② ♥ ①♠♦ ♥tr ♠t♦ ♦r ♥②ss ♦ rtr

♣r♦♠s s♥ ♥♥r♥ ♥②ss t ♦♥r② ♠♥ts

❬❪ ♥ ♥ ❲ trss ♥t♥st② t♦r ♦♠♣tt♦♥ ♦♥ ♥♦♥♣♥r r

r ♥ tr ♠♥s♦♥s ♥tr♥t♦♥ ♦r♥ ♦ ♦s ♥ trtrs

❬❪ P s♦ ♥ tr t♦♥ ♦ rtr ♠♥s ♣r♠trs ♦r ♥ r

trr② tr♠♥s♦♥ r ② t ❵q♥t ♦♠♥ ♥tr ♠t♦ ♥tr♥t♦♥

♦r♥ ♦r ♠r t♦s ♥ ♥♥r♥

❬❪ ♠r ♥ ♥ q♥t ♦♠♥ ♥tr ♠t♦ ♦r tr

♠♥s♦♥ ♠①♠♦ rtr ♣r♦♠s ♥♥r♥ rtr ♥s

❬❪ r ♥ ♥ ♥ t ♦♠♣♦st♦♥ ♦ t ♥tr ♦r r

♣r♦♠s ♥tr♥t♦♥ ♦r♥ ♦ rtr

❬❪ ② ♥ ♦♠♣♦st♦♥ ♦ t ♠①♠♦ ♥trrst

♥tr♥t♦♥ ♦r♥ ♦ ♦s ♥ trtrs

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❬❪ ♦s③ ♥ ♦r♥ ♥ ♥trt♦♥ ♥r② ♥tr ♠t♦ ♦r ♦♠♣tt♦♥ ♦ ♠①

♠♦ strss ♥t♥st② t♦rs ♦♥ ♥♦♥♣♥r r r♦♥ts ♥ tr ♠♥s♦♥s ♥♥r

♥ rtr ♥s

❬❪ P s♥♦ ♥ rt③ ♦♥r② ♠♥t ♥②ss ♦ tr♠♥s♦♥ ♠①♠♦

rs t ♥trt♦♥ ♥tr ♦♠♣tr t♦s ♥ ♣♣ ♥s ♥ ♥

♥r♥ r

❬❪ r ♥ ❲r♦ ♦♥r② ♠♥t ♠t♦ ♦r ①s②♠♠tr r

♥②ss ♥tr♥t♦♥ ♦r♥ ♦ rtr

❬❪ r♦♥ ♥ ♥ t r①t♥s♦♥ ♥ ♣ts ♥r ♣♥ ♦♥ ♥ tr♥srs

sr ♦r♥ ♦ s ♥♥r♥

❬❪ ♠r ♦♣♣ ♥ ♦r♥ ①t♥ ♥t ♠♥t ♠t♦ ♥ st ♠r♥

♠t♦ ♦r tr♠♥s♦♥ t r ♣r♦♣t♦♥ ♥♥r♥ rtr ♥s

♥r②