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일반적인 음원에 의해 발생되는 파의 종류를 그림(5.1)에 나타내었으며, 각각의 환경 에 대해 파가 존재하는 조건이 다양하므로 실제 환경에 대해 존재하는 현상을 이해하 기 위해 좀더 많은 연구를 필요로 한다. 특히 구형의 층상화에 대한 음향 에너지 전달 의 경우 이론적인 공식에서 의하면 유체/ 탄성 영역은 크게 소실되어 지는 것으로 알 려져 있지만 실제 환경에 적용하기 위해서는 구형의 층상화에 대해 해석적 해를 구해 야 한다.

본 논문에서 개발된 모델은 기본적으로 세 개의 층으로 구성된 접수 평판의 환경에 대해 적용된 것이지만 좀 더 현실적인 문제에 있어 수중 음향 반향체의 코팅에 의한 반사 손실을 측정하기 위한 모델이나 앞서 언급한 유체 소음 판(plate) 또는 표면 처리 된 판(coated plat)에서 음향 에너지의 방사 형태에 관한 모델링을 위해 확장할 수 있 다.

A ppe ndix

A 1. D ip S lip

▷ Potentials

= M0

4 w2 eiwt

0

- 0. 5 s in 2 ( 2 2+ k2)J0( kr ) - 2 cos 2 k s in J1( kr ) - 0. 5 s in 2 k2cos 2 J2( kr )

e- | z - zs|k dk

= M0

4 w2 eiwt

0

- 1. 5 s in 2 J0( kr ) - cos 2 2k2- k22

k s in J1( kr ) - 0. 5 s in 2 cos 2 J2( kr )

e- | z - zs|k dk

= M0

4 w2 eiwt

0

+ cos 2 k2

k cos J1( kr ) - 0. 5 s in 2 k2s in 2 J2( kr )

e- | z - zs|k dk

▷ Dis place me nts and s tres s e s

F or zeroth order,

wm = eiwt 4 w2 M0

0

[

0. 5 s in 2 ( 2 2+ k2) e - | z - zs|

]

- 1. 5 s in 2 k2e- | z - zs| J0( kr ) k dk

um+ vm= eiwt 4 w2 M0

0

0. 5 s in 2 ( 2 2+ k2) k

e- | z - zs| - 1. 5 s in 2 k e- | z - zs|

J1( kr ) k d k

um- vm= eiwt 4 w2 M0

0

- 0. 5 s in 2 ( 2 2+ k2) k

e- | z - zs| 1. 5 s in 2 k e- | z - zs|

J- 1( kr ) k dk

m

z z= eiwt 4 w2 M0

0

- 0. 5 s in 2 ( 2 2+ k2)( 2 2- k2) 1

e- | z - zs| + 3 s in 2 k2 e- | z - zs|

J0( kr ) k dk

m

r z+ mz= eiwt 4 w2 M0

0

[

+ 1. 5 s in 2 k (- s in 2 k ( 2 22+ k+ k22) e) e-- | z - z| z - zs|s|

]

J1( kr )k dk

m

r z- mz= eiwt 4 w2 M0

0

[

+ s in 2 k ( 2 2+ k2) e- | z - zs|

]

- 1. 5 s in 2 k ( 2+ k2) e- | z - zs| J- 1( kr )k dk

F or s in order,

wm= eiwt 4 w2 M0

0

2 cos 2 k e- | z - zs| - cos 2 ( 2 k2- k2m) k

e- | z - zs|

J1( kr ) k dk

um+ vm= eiwt 4 w2 M0

0

[

- 2 cos 22 cos 2 k2ke2e-- | z - z| z - zs|s|

]

J2( kr ) k dk um- vm= eiwt

4 w2 M0

0

[

- 2 cos 2+ 2 cos 2 k22ee-- | z - z| z - zss||

]

J0( kr ) k dk

m

z z= eiwt 4 w2 M0

0

[

+ 2 cos 2- 2 cos 2 k ( kk ( k22++ 22) e)e-- | z - z| z - zss||

]

J1( kr ) k dk

m

r z+ mz= eiwt 4 w2 M0

0

- 4 cos 2 k2e- | z - zs| + cos 2 k2

( 3 3+ k2) e- | z - zs|

J2( kr )k dk

m

r z- mz= eiwt 4 w2 M0

0

4 cos 2 k2e- | z - zs| - cos 2 ( 2 3+ k4

+ k2) e- | z - zs|

J0( kr )k dk

F or cos 2 order,

wm = eiwt 4 w2 M0

0

[

+ 0. 5 s in 2 k2e- | z - zs|

]

- 0. 5 s in 2 k2e- | z - zs| J2( kr ) k d k

um+ vm= eiwt 4 w2 M0

0

0. 5 s in 2 k3

e- | z - zs| - 0. 5 s in 2 k3

e- | z - zs|

J3( kr ) k dk

um- vm= eiwt 4 w2 M0

0

- 0. 5 s in 2 k3

e- | z - zs| - 0. 5 s in 2 ( k2- 2 2) k

e- | z - zs|

J1( kr ) k dk

m

z z= eiwt 4 w2 M0

0

- 0. 5 s in 2 ( k2+ 2) k2

e- | z - zs| + s in 2 k2 e- | z - zs|

J2( kr ) k d k

m

r z+ mz= eiwt 4 w2 M0

0

[

-+ s in 2s in 2 kk33ee-- | z - z| z - zss||

]

J3( kr )k dk

m

r z- mz= eiwt 4 w2 M0

0

[

- s in 2s in 2 kk3e2-e-| z - z| z - zs| s|

]

J1( kr )k dk

A .2 S trike- S lip

▷ Potentials

= - M0

4 w2 eiwt

0

[

s in s in 2 k2J2( kr )

]

- 2 cos cos k J1( kr ) e- | z - zs|k dk

r= - M0

4 w2 eiwt

0

[

s in s in 2 k J1( kr )

]

- cos cos J0( kr ) e- | z - zs|k dk

= - M0 4 w2 eiwt

0

[

s in s in 2 k J1( kr )

]

+ cos cos J0( kr ) e- | z - zs|k dk

z= M0

4 w2 eiwt

0 cos cos k J1( kr ) e | z - zs|k d k

또는,

= - M0

4 w2 eiwt

0

[

s in s in 2 k2J2( kr )

]

- 2 cos cos k J1( kr ) e- | z - zs|k dk

= M0

4 w2 eiwt

0

cos cos k 2k2- k22 k J1( kr ) - s in cos 2 J2( kr )

e- | z - zs|k d k

= M0

4 w2 eiwt

0

cos s in k2m k J1( kr ) + s in cos 2 k2J2( kr )

e- | z - zs|k dk

▷ Dis place me nts and s tres s e s

F or cos order,

wm= eiwt 4 w2 M0

0

- 2 cos k e- | z - zs| cos ( 2 k2- k2m ) k

e- | z - zs|

J1( kr ) k dk

um+ vm= eiwt 4 w2 M0

0

[

- 2 cos+ 2 cos kk22ee-- | z - z| z - zss||

]

J2( kr ) k dk um- vm= eiwt

4 w2 M0

0

[

+ 2 cos- 2 cos k22ee-- | z - z| z - zss||

]

J0( kr ) k dk

m

z z= eiwt 4 w2 M0

0

2 cos k ( 2k2- k2m)e- | z - zs| - 2 cos k ( 2k2- k2m) e- | z - zs|

J1( kr ) k dk

m

r z+ mz= eiwt 4 w2 M0

0

4 cos k2e- | z - zs| - cos ( k4

+ 3 k2) e- | z - zs|

J2( kr )k d k

m

r z- mz= eiwt 4 w2 M0

0

- 4 cos k2e- | z - zs| cos ( 2 3+ k4

+ k2) e - | z - zs|

J0( kr )k dk

F or s in 2 order,

wm = eiwt 4 w2 M0

0

[

-s ins in kk22ee-- | z - z| z - zs|s|

]

J2( kr ) k d k um+ vm= eiwt

4 w2 M0

0

s in k3

e- | z - zs| - s in k3

e- | z - zs|

J3( kr ) k d k

um- vm= eiwt 4 w2 M0

0

- s in k3

e- | z - zs| - s in ( k2- 2 2) k

e- | z - zs|

J1( kr ) k d k

m

z z= eiwt 4 w2 M0

0

- s in ( 2k2- k2m)k2

e- | z - zs| + 2 s in k2 e- | z - zs|

J2( kr ) k d k

m

r z+ mz= eiwt 4 w2 M0

0

[

- 2 s in+ 2 s in kk33ee-- | z - z| z - zss||

]

J3( kr )k dk

m

r z- mz= eiwt 4 w2 M0

0

[

- 2 s in2 s in kk3e2-e-| z - z| z - zs| s|

]

J1( kr )k d k

A .3 T ens ile Crac k

M1 = M0, 1= 90。

M2 = M0, 2= + 90。 , an d M3 = + 2

M0, 3 =

ex cept that M1 = - M0 w hen m = 2, cos 2 order.

▷ Potentials

=

k = 1 'k( r , , z : k, Mk)

r=

k = 1 'r , k( r , , z : k, Mk)

=

k = 1 ' , k( r , , z : k, Mk)

z=

k = 1 'z , k( r , , z : k, Mk)

w here the potentials w ith prim e (' ), w hich is a s ingle couple w ithout m om ent, are

'k= - Mkeiwt 4 w2 0

[

+ 0. 25 cos 2- 0. 25( k2k- 2( k2+ 22) 2)

]

J0( kr )

- s in 2 ks in k J1( kr ) - 0. 25 ( 1 - cos 2 k) cos 2 k2J2( kr )

e- | z - zs|k dk

'r , k= - Mkeiwt 4 w2 0

- 0. 5 s in 2 ks in J0( kr )

[

0. 25( 1 - cos 2 k)

- 0. 25 ( 1 - cos 2 k) cos 2 k

]

J0( kr )

e- | z - zs|k dk

' , k= - Mkeiwt

4 w2 0

[

- 0. 5 s in 2 kcos J0( kr )

]

0. 25( 1 - cos 2 k) cos 2 k J0( kr ) e- | z - zs|k dk

'z , k= - Mkeiwt

4 w2 0

[

- 0. 5 ( 1 + cos 2 k) J0( kr )

]

- 0. 5 s in 2 ks in k J0( kr ) e- | z - zs|k dk

▷ Dis place me nts and s tres s e s

wm( r , z ) =

3

k = 1wmk ( r , z ) um( r , z ) + vm( r , z ) =

3

k = 1umk ( r , z ) + vmk ( r , z )

F or zeros order,

wmk = eiwt 4 w2 Mk

0

[ 0. 25( k2- 2 2) - 0. 25 cos 2 k( k2+ 2 2) ] e- | z - zs| ( 0. 25 + 0. 7 5 cos 2 k) k2e | z - zs|

J0( kr ) kd k

umk+ vmk = eiwt 4 w2 Mk

0

0. 25( k2- 2 2) k

- 0. 25 cos 2 k( k2+ 2 2) k e- | z - zs| ( 0. 25 + 0. 7 5 cos 2 k) k e | z - zs|

J1( kr ) kdk

umk- vmk = eiwt 4 w2 Mk

0

- 0. 25( k2- 2 2) k

- 0. 25 cos 2 k( k2+ 2 2) k e- | z - zs| - ( 0. 25 + 0. 75 cos 2 k) k e | z - zs|

J- 1( kr ) kdk

m

z z , k= eiwt 4 w2 Mk

0

- k2+ 2

[

- 0. 25 cos 20. 25( k2- 2k( k2+ 22) 2)

]

e- | z - zs|

- ( 0. 5 + 1. 5 cos 2 k) k2e | z - zs|

J0( kr ) kdk

m

r z , k+ m, k = eiwt 4 w2 Mk

0

[

+ 0. 5 cos 2- 0. 5( k2k- 2( k2+ 22) k2) k

]

e- | z - zs|

- ( 0. 25 + 0. 75 cos 2 k) k ( s2+ 2) e | z - zs|

J1( kr ) kdk

m

r z , k- m, k = eiwt 4 w2 Mk

0

[

- 0. 5 cos 20. 5( k2- 2k( k2+ 22) k 2) k

]

e- | z - zs|

( 0. 25 + 0. 7 5 cos 2 k) k ( s2+ 2) e | z - zs|

J- 1( kr ) kdk

F or s in order,

wmk = eiwt 4 w2 Mk

0

k s in 2 ke- | z - zs| - 0. 5 k

( 2+ k2) e- | z - zs|

J1( kr ) kdk

umk+ vmk = eiwt 4 w2 Mk

0

+ k2s in 2 ke- | z - zs| - k2s in 2 ke- | z - zs|

J2( kr ) kdk

umk- vmk = eiwt 4 w2 Mk

0

- 2 s in 2 k k2e- | z - zs| + 2 s in 2 k 2e- | z - zs|

J0( kr ) kdk

m

z z , k= eiwt 4 w2 Mk

0

- 2 s in 2 k k ( k2+ 2) e- | z - zs| + 2 s in 2 k k ( k2+ 2) e- | z - zs|

J1( kr ) kd k

m

r z , k+ m, k = eiwt 4 w2 Mk

0

- 2 s in 2 k k2e- | z - zs| + 0. 5 s in 2 k k2

( 2 2+ k2) e- | z - zs|

J2( kr ) kdk

m

r z , k- m, k = eiwt 4 w2 Mk

0

2 s in 2 k k2e- | z - zs| - s in 2 k( 3+ 0. 5k4

+ 0. 5 k2) e- | z - zs|

J0( kr ) kdk

F or cos 2 order

wmk = eiwt 4 w2 Mk

0

+ 0. 25 k2( 1 - cos 2 k) e- | z - zs| - 0. 25 k2( 1 - cos 2 k)e- | z - zs|

J2( kr ) kdk

umk+ vmk = eiwt 4 w2 Mk

0

+ 0. 25k3

( 1 - cos 2 k) e- | z - zs| - 0. 25k3

( 1 - cos 2 k) e- | z - zs|

J3( kr ) kdk

umk- vmk = eiwt 4 w2 Mk

0

- 0. 25k3

( 1 - cos 2 k) e- | z - zs| - 0. 25 ( k2- 2 2)k

( 1 - cos 2 k) e - | z - zs|

J1( kr ) kd k

m

z z , k= eiwt 4 w2 Mk

0

- 0. 25( k2+ 2)k2

( 1 - cos 2 k) e- | z - zs| + 0. 5k2 ( 1 - cos 2 k) e- | z - zs|

J2( kr ) kdk

m

r z , k+ m, k = eiwt 4 w2 Mk

0

- 0. 5 k3( 1 - cos 2 k) e- | z - zs| + 0. 5 k3( 1 - cos 2 k) e- | z - zs|

J3( kr ) kd k

m

r z , k- m, k = eiwt 4 w2 Mk

0

[

- 0. 5 k+ 0. 5 k3e2e-- | z - z| z - zs|s|

]

J1( kr ) kdk

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