Development of Nuclear Fuel Rod Testing Technique Using ...

KR9700258KAERI/RR-1680/96

Development of Nuclear Fuel Rod Testing Technique

Using the Ultrasonic Resonance Phenomena

29 - 0j

KAERI/RR-1680/96

Development of Nuclear Fuel Rod Testing Technique

Using the Ultrasonic Resonance Phenomena

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1997 \i 2 € I7°i

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i.

^ ^ p r e s s u r i z e d water reactor: PWR)H

300 7fl^ ^^ .^^-^( fue l bundle)!-^-

^ 200 <^7fl^ <23.-g-(fuel rod)^)-, ^

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examination: PIE) -f-ofl

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£ 71*113. 7}^% S )^ -^ , 2 ) ^ - ^ 4 « A f o ^ 7^(gap)oH

, ( ultrasound

spectroscopy system: RUSS)# ^ W . S.^:, ^ ^ ^ fl-S^l ^ ^ - ^

(leak-defective fuel rod detection system: LFRDS)-

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vii ISSXT FAGE(S)left BLANK

SUMMARY

I. Project Title

Development of Nuclear Fuel Rod Inspection Technique Using Ultrasonic

Resonance Phenomena

II. Objective and Importance of the Project

The core of the pressurized water reactors contain about three hundred fuel

bundles. Each fuel bundle, which is of type of rectangular parallelpipe, consists of about

two hundred fuel rods, some guide tubes, spacer grids, and top and bottom nozzles. Each

fuel rod consists of uranium dioxide pellets, a Zircaloy-4 cladding tube, plenum spring(s),

etc. The ends of the rod are sealed with end plugs by welding. Plenum is the internal

space for accumulating the fission gases. For the safe and economic operation of a

nuclear power plant, it is very important to secure the structural integrity of the cladding

tube, which is the first barrier against the release of radioactive fission gases. Therefore a

number of non-destructive testing (NDT) methods have been applied in the various

stages of fuel manufacturing, in-service inspection (ISI) and post-irradiation examination

(PIE).

The current NDT methods to evaluate the extent of failure of in-service or spent

fuel rods are the eddy current testing (ECT) and the ultrasonic testing (UT). The former

is used to examine flaws in the cladding tube and the latter to detect the presence of

water in the gap between cladding tube and pellet, which is indicative of cladding tube

ix

failure. ECT is also used to measure the thickness of oxide layer on the outside surface of

the cladding tube and it is rather simpler than UT in view point of detecting flaws in the

cladding tube, but it requires disassembling of the fuel bundle for testing. UT does not

require the disassembling but its reliability is not so high that, in ISI, the leak-defective

fuel rods detected by UT have been re-examined by ECT. There were many cases that a

rod evaluated as a leak-defective fuel rod by UT is evaluated as a sound rod by ECT, and

vice versa.

Recently, a new UT technique has been developed, which has potential of

detecting the water presence as well as flaws, dimensions and material property change

of the cladding tube. This new technique takes advantage of ultrasonic resonance

phenomenon which is attributed to elastic waves circumnavigating the tube (so-called

"circumferential waves"). In the simulation experiment using a pre-irradiated fuel rod, it

was already shown that this technique can detect the presence of water clearly. The

purpose of this project is to apply the new UT technique to ISI and PIE.

HI. Scope and Contents of the Project

In the first year (1995) of this project, some basic techniques had been developed

for modeling of the acoustic resonance scattering (ARS) by a nuclear fuel rod,

measurement of ultrasonic resonances, and design and manufacturing process of thin

(less than 2 mm) ultrasonic sensors. Particularly, an experimental system for measuring

the resonances of a disassembled spent fuel rod was constructed at the post-irradiation

examination facility (PIEF) in our institute and excellent detection ability of the new UT

for the leak-defective fuel rods was successfully demonstrated.

In the second year(1996), the ARS modeling code developed in the first year has

been extended to be applicable to an multilayered cylindrical shell. An empty cladding

tube, a fluid-filled cladding tube, a pre-irradiated fuel rod with helium gas gap, a leak-

defective fuel rod with water gap, and an in-service or spent fuel rod with zirconium

oxide layer on the outer and/or inner surfaces of the cladding tube can be dealt as an

example of the multilayered cylindrical shell. And the resonant ultrasound spectroscopy

system (RUSS) has been constructed to evaluate the effectiveness of the developed ARS

modeling code. The leak-defective fuel rod detection system (LFRDS) of a laboratory

scale has been also constructed to develop the ISI technique taking advantage of the

resonances of the cladding tube.

IV. Results and Proposal for Applications

The scattering of plane acoustic waves normally incident on a multilayered

cylindrical shell has been formulated using the global matrix approach. This is to

represent each boundary condition as a matrix (so-called "boundary matrix") equation

and to simply add all boundary matrix equations. Therefore this approach allows us to

represent all boundary conditions as a single matrix (so-called "global matrix" or

"system matrix") equation and to obtain the elements of the system matrix for any shell

with arbitrary structure easily and correctly.

A simple approach to formulate a non-resonant background component in the field

scattered by an empty elastic shell has been founded. This is to replace the surface

XI

admittance for the shell with the zero-frequency limit of the surface admittance for the

analogous fluid shell (i.e., where the shear wave speed in the elastic shell is set to zero).

Justification for this replacement comes from noticing that, when the waves that give rise

to resonances in the shell are damped out, the surface admittance is well approximated

by that for the analogous fluid shell and is practically constant as a function of frequency.

Therefore it can be hypothesized that the constant part of the surface admittance should

be used to obtain the background and the simplest way to obtain this part for a

nonattenuating shell, given there are no resonances to modify the surface admittance at

zero frequency, is to extract it as the zero-frequency limit of the surface admittance for

the fluid shell. It has been analytically and numerically shown that the background thus

obtained, which is named "inherent background" here, is exact and applicable for shells

of arbitrary thickness and material makeup, and over all frequencies and mode numbers.

The exact expressions of the background components for multilayered shells of

arbitrary structure have been founded using the inherent background approach and their

effectiveness has been also demonstrated. The inherent background approach is

applicable to other goemetries; for an example, the approach for spherical geometry is

identical to that for cylindrical geometry, with the exception of replacing the cylinder

functions by the corresponding spherical functions.

RUSS has been constructed to measure the resonance spectrum of a single fuel rod

and to evaluate the effectiveness of the developed ARS modeling code. It consists of an

ultrasonic system, a scanner system, and a computer system. The ultrasonic system

contains ultrasonic transducers, a pulser and receiver, and a waveform digitizer. The

xu

scanner system contains a water tank, a stepping motor driving turn-table and two-axis

slide unit, and a motor controller. The computer system controls the scanner controller,

the pulser and receiver, and the waveform digitizer, and it acquires and analyzes the

scattered signals. The resonance spectrum of a fuel rod is obtained using the mono-static

pulse-echo method, and the order of each resonance is determined using the bi-static

pulse-echo method. The measured resonance spectrum is in good agreement with the

spectrum predicted by the ARS modeling code.

LFRDS of a laboratory scale has been constructed to develop the ISI technique. It

consists of an ultrasonic flaw detector, an ultrasonic probe of thin (thickness of 1.2 mm)

strip type, a scanner system, a standard (non-irradiated) fuel bundle, and a computer

system. The scanner system contains an water tank, a stepping motor driving three-axis

slide unit, and a motor controller. The computer system controls the scanner controller

and it acquires and processes signals from the flaw detector. Particularly, all techniques

and processes necessary for manufacturing the ultrasonic probe have been developed and

some prototype probes have been manufactured.

I &EXT PAQE(S)left BLANK

iii

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xvi

Figure 2-1. (a) The modal surface admittance (divided by the fluid-loading-

parameter) GJ,L) of the lowest order (« = 0) partial wave for the liquid shell

(h = 05 and CL=57%Qms~l) without any consideration of structural

damping in water (C, = 1480 m.?"1), and (b) the real parts of the modal

surface admittance for various structural-damping coefficients /3L, plotted as

a function of frequency. 13

Figure 2-2. G(nL)(0+) of the first six (n = 0 ~ 5) partial waves plotted as a

function of relative shell-thickness. 17

Figure 2-3. (a) Moduli and (b) phases (in radian) of the total backscatteringform functions of the inherent backgrounds for the 2% (dash-and-dot line) and99% (solid line) thick, empty, stainless-steel shells in water, as well as those ofthe rigid (dotted line) and soft (dash-and-two dots line) backgrounds. 19

Figure 2-4. Moduli of the residual backscattering form functions, | / n - / n( A ) | ,

for the lowest six (n - 0 ~ 5) partial waves for the 2% thick, empty, stainless-steel shell in water. 21

Figure 2-5. Geometry of a plane acoustic wave scattering from a multilayeredcylindrical shell. 25

Figure 2-6. Geometry of a plane acoustic wave scattering from an emptydoublelayered elastic cylindrical shell. 45

Figure 2-7. Comparison between the inherent background amplitudes(dottedline) and the backscattering amplitudes (solid line) of the partial waves for an12% thick, empty Zircaloy shell with 10// m thick ZrO2 layer. 47

Figure 2-8. Resonance spectra of the partial waves for an 12% thick, emptyZircaloy shell with 10 // m thick ZrO2 layer. 48

Figure 2-9. Resonance spectra of the (a) «=4 and (b) n=10 partial waves for12% thick, empty Zircaloy shells with the various thickness (10/an, 20//m,50/an, 100/an) of ZrO2 layer 49

xvu

Figure 3-1. Schematic diagram of the resonant ultrasound spectroscopy system. • • 53

Figure 3-2. Overall view of the resonant ultrasound spectroscopy system: (a)scanner, (b) turn table, (c) computer, (d) scanner controller, (e) waveformdigitizer, and (f) pulser & receiver. 54

Figure 3-3. Signal waveform and frequency spectrum of the 0.5 MHztransducer 57

Figure 3-4. Signal waveform and frequency spectrum of the 1.0 MHztransducer. 58





Figure 3-9. Signal waveform and frequency spectrum of the 10 MHztransducer. 63

Figure 3-10. Drawing of the turn table. 64

Figure 3-11. Photograph of the turn table. 65

Figure 3-12. Backscattering echoes obtained from the fuel rod using the 1MHz transducer. c-i

Figure 3-13. Backscattering echoes obtained from the fuel rod using the 2.25MHz transducer. 68

Figure 3-14. Resonance spectrum of the cladding tube obtained using 1 MHztransducer. Here, n denotes the normal mode number. Left number in theparenthesis is resonance frequency measured experimentally and right numberis resonance frequency calculated theoretically. 70

xvin

Figure 3-15. Resonance spectrum of the cladding tube obtained using 2.25MHz transducer. Here, n denotes the normal mode number. Left number in theparenthesis is resonance frequency measured experimentally and right numberis resonance frequency calculated theoretically. 71

Figure 4-1. Different vendors' probes of ultrasonic testing (quoted fromReference [2]). 74

Figure 4-2. Schematic diagram of the leak-defective fuel rod detection system. • • • 78

Figure 4-3. Overall view of the leak-defective fuel rod detection system: (a)scanner, (b) xy slide unit, (c) fuel assembly, (d) computer, (e) scannercontroller, (f) flaw detector, and (g) waveform digitizer. 79

Figure 4-4. Photograph of the ultrasonic probe. 82

Figure 4-5. The ultrasonic probe mounted in the xy slide unit. 84

Figure 4-6. Drawing of the slide unit. 85

Figure 4-7. Schematic diagram of the ultrasonic sensor designed for fuelassembly inspection. 87

Figure 4-8. Drawing of the ultrasonic sensor housing. 90

Figure 4-9. Drawing of the probe strip 92

Figure 4-10. Drawing of the probe strip holder. 94

x ix

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complex conjugate <>]4. 22) )^ , ^^-^-^r Sn-&

(scattering phase shift) 5n ^ ^ . S . i ^ ^ ^ $icf:

5n=exp(2/5J. (35)

- 3 3 -

2.4.

2.2

^nl1i^£l zero-

frequency limits. tflSfl f- - 3 H 4 . ol

o f l ^ u l ^ ^ ^ AOU|. - - 1 ^ofl

o] ^ - ^ AJ W.-O- ^ ^ 7].^- - ^ - ^ HOV^^. z e r o frequency e ^

^^r-s ^ ^ ^ 1 ^ ^ ° 1 § 1 ^ AoV4 -n- 11 € ^ 1 zero-frequency

limit ^ 1 °] ^ ^ ^ 1 W f ^ ^ 1 4

^ ^ 1 , W -fV ll ^ ^ ^ ^ l ^ r S ^ afl-Einm^-I- -fVS^cf. H?)3L 0}

^ 1 ^ ^ ^ zero-frequency limit 1-

Zircaloy-4

- 3 4 -

2.4.1. -^(analogous) T

2-5

36-38

-9-si y(=2,3,..., m -

(36)»=o

n=0

=£eBi-[(7;(I))>yj,(*wr)]cosiie . (38)N=0

^7 = ^ + i ' UJ = UJ+I U = l2,...,m-\). (40)

2.3.2^H H ^ 5J4 ^-^ €^1-1- 4 ^ ^ , ^ 23 4 ^-4-

- 3 5 -

Jn{Xj)XjJn'(Xj)

Pm-l

E -

(41a)

(41b)

(41c)

(41d)

(41e)

(41f)

(41g)

-§•4

P2

(42)

- 3 6 -

*-y2^±. (45)P 2 Jniyi)

44

^ 4A]

Hankel ^ - ^ / ^ l ) ( ^ 2 ) 4 ° 1 ^ Hankel

2)^1 Ai ^Aj^o^w.^

^ 1 °14. o] nfl,

- 3 7 -

P. ,. ^•(y2)(SiL))2+H?)'(y1) (47)

£>„

P2

PiP2

(48)

4 3 4 AI 44

" P2

(49)

Bessel t H r ^ Neumann f-^rt- Hankel ^ 1 : 49 fe- 4 ^ 4

47

40.4

- 3 8 -

D ={0} i$ n

P2

o J,0 x^

-

0

0

44

^ 4 ^ 4 7 -0)

(50)

2Hn

P3 JJ

^ ^ 45 °11

. Bessel tJ^rir Hankel

4 7 01

(5^)3 = 1.

(51)

(52)

52

(53)

- 3 9 -

{L)) =^±v. - i ^ — (55)

53 1- ^ 55°fl tfl^*}1^, 4-5-^f £ £ ^^^(recurrence relation)^:

JYB

JYD

^ 1 °)B.S.,

- 4 0 -

(56a)

= Jn'(yJ)Yn'(xJ)-Jn'(xJ)Yn'(yj) , (56b)

= Jn\yj)Yn{xJ)-Jn(xj)Yn\yj) , (56c)

= Jn(yJ)Yn'(xj)-Jn'(xJ)Yn(yJ) , (56d)

= y, (^. )yB (Xj ) - yB (x,. )Yn (yj ) . (56e)

2.4.2. :H

2.2.5

» D(57)

oflôlîô] Zero-frequency limit

10o)l M-E vfl B e s s e l -%^ Neumann ^-^r^ ^ 4 ^ 1 : ^ : ^ 56 °fl

P, l-ln(l-A,)(Fn( i )(0+

(58a)

(58b)

q.=n J-^ . (58c)

- 4 1 -

(59)

^ n ] ^ ^ F n( L ) (0 + ) ^ ^ 58^1

(60)

^g-f,

2.2.3 11-1-

- 4 2 -

.+£-

2.4.3.

<?l Zircaloy-4 2)

1 0 - 2 0 0 ^ m ^ ^ ^ oiA]-^-xl5.3.^-(ZrO2)

- 4 3 -

( 6 2 )

(63)

2-6 4

1, *\ 3, ZL51JL ^] 9 ^

D?

{0}{0}

D: {0,}

{0} D](64)

Fn^(0+) =- P i

(65a)

1 +

F£Ho*)=*±n . ,, 1;(!.-*')2'\2n

P2

p 3 1 - O -

(65b)

l, Df±. 3 x 1 , £ ) ^ 3x2 , D * ^ D ^ 4x4 ,

^ 2 x 4 9 x 9

C i

- 4 4 -

Figure 2-6. Geometry of a plane acoustic wave scattering from an emptydoublelayered elastic cylindrical shell.

- 4 5 -

fe JL

ZrO2

Zircaloy-4 ^ 4 ^ 6 f l ^^fl ^ ^ t t 4 . ^ ^ - ^ ^ ] ^ f l

>JL ^B]D-]-fi) AJ"ifl-T^ll(/»2)^ 0.1%, 0.2%, 0.5%, 1.

19mm ?1 9 | l ^ * ) ~ f ^ 17x17 < ? ! ^ s ] 4 : a ^ ^-f, ° l ^ ^ r 0.57mm

=0-100, Ax, =0.05

p2=5.6gcm-3, p3 =6.55gcm-3, C, = 1480ms"1,

C2£ =7100ms-1, C^SSOOms"1, C\ = 4600ms"1, C3

r =

Zl^ 2 - 7 ^ 0.1% M|i*l -a-^-^nj.^- ^ ^ - s]^-^ofl tfl*> ^ cf^ 7fl

2-8

Lamb 4°fl 7l«]^4. ^ ^ 2-9

- 4 6 -

20 40 60 80 100

Figure 2-7. Comparison between the inherent background amplitudes(dotted line)and the backscattering amplitudes(solid line) of the lowest five(n=0~4) partial wavesfor the 12% thick, empty Zircaloy shell with lOfam thick ZrO2 layer.

- 4 7 -

3

O

20 40 60

k.,a

80

n=0

n=1

n=2

n=3

n=4

n=12

n=16

n=20

100

Figure 2-8. Resonance spectra of the partial waves for the 12% thick, emptyZircaloy shell with lOjam thick ZrO2 layer.

- 4 8 -

20 40 60 80 100

60 80 100k.,a

Figure 2-9. Resonance spectra of the (a) «=4 and (b) «=10 partialwaves for 12% thick, empty Zircaloy shells with the various thickness

, 20fim, 50|am, lOO^m) of ZrO2 layer.

- 4 9 -

rt]. 3 3 . ^

- 5 0 -

3.1.

ol -(resonance scattering theory: RST)°fl

: 1981 Vl S . ^ Le Havre t f l ^ RipOche iL^r ^ H 5]«fl ^

^- JL^S] $4.[25-28] Quasi-harmonic MIIR(Method of Isolation and Identification of

Resonances)^.

toneburst

4 ^fl^Hl ^3. 7}

, Rayleigh

normal mode number)"^)

- 5 1 -

short-pulse MIIR ofl ^«fl # ^ € T £ &4.[29-30]

FFT(Fast Fourier Transform)^"°-£.tf ^ i ^ j S ^ ^ - Q&ty. °1 yo>

wJ-^l-(quasi-harmonic MIIR 4 short-pulse

^ o)

3.2.

3-1 4 H ^ 3-2^

-52 -

Transmitter/ReceiverTransducer

ReceiverTransducer

Water

Scanner

Pulser & Receiver

(Ritec RAM 10000)

Waveform Digitizer

(Tek.RTD710A)

ADAC4801A GPIB

RS232C

Computer

Controller Printer

Figure 3-1. Schematic diagram of the resonant ultrasound spectroscopy system

- 5 3 -

Figure 3-2. Overall view of the resonant ultrasound spectroscopy system: (a)scanner, (b) turn table, (c) computer, (d) scanner controller, (e) waveformdigitizer, and (f) pulser & receiver.

- 5 4 -

S ] ^ 3(x, y, z)

^ scanner^ turntable, H^JL J2.B]-

5.*}- ^S l -e i , ^^

^ monostatic pulse-echo (MPE) u j " ^ A S <ô] x l ^ z]- ^-ô) ^ > ^ ^ ^ A | &•

^•AQ ^r^l ^-#^1-71- ^ e ) 5 i ^ bistatic pulse-echo (BPE) " J ^

BPE 1 W H ^r^l ^ ^ r f e turn table

. 4 -¥- -

Litec 4^1 RAM-0.25-17.5 Mark VI Mr *}-%-*}Sm. °1 ^ ^ 1 ^ 250

î 10 MHz ^ o f H ^cfl 1.5 kW (in RMS), 17.5 MHz

1.0 kW(in RMS)^ RF toneburst ^ ^ 1 - V ^ A 1 ^ ^r 9X^-, 78 dB

ADAC4801A ?>=.-!• -i-«l| IBM 586PC °fl

Tektronix/Sony RTD 710A1- ^}-%-t}<^t\; ^ cfl sampling rate fe 200 MHz,

^ ^ r 10 bit, ^ l l i e l ^ 640kB <>14. GPIB 5

- 5 5 -

-^c: Tektronix SPD(signal processing and display) i 5 . S

Panametrics * H VideoScan series(0.50, 1.00, 2.25, 3.50, 5.00, 7.50, 10.00

MHz)t- 4-g-*>^4. ^ 3-3 <HH n ^ 3-9 4*1TT °1

"l-5f Metrotek 4 ^ C403 system^-

1.1 m(L) x 0.6 m(W) x 0.5 m(H) olcf. ^ 2 :

o] ol ig;E<>11 5]«fl ^p-g-ilfe 3(x, y, z)-% scanner 7> ^2)"^cf. o] scanner fe

^ 0.05 mm o)cf. %$-B\9}- SLt\-

fe RS232CS <31€4.

i ] ^ ^ ^ ^ ^ ^ ^ ^^\] %n^= BPE

turn table °fl £]«fl QtfQty. ^l^Nl-c- °1 turn tabled

QQ ^- 3 ^ scanner °fl ^ 2 } - ^ -^-^^1 l l^l l^ jig °fl

3-10 4 ^ - ^ 3-11 r turn tabled 7])x\

- 5 6 -

SIGNAL WAVEFORM

( 2 USEC / DIVISION )

FREQUENCY SPECTRUM1.0

0.8

0.6 ~

0.4 —

0.2 —

0.0

-

-

-

-

.31

j

/

j

1

(

-6dB

\

V615

\

\ ^ _.

\

—I k0 0 0.5

(MHz)1.0

Figure 3-3. Signal waveform and frequency spectrum of the 0.5 MHz transducer.

- 5 7 -

SIGNAL WAVEFORM0.8

0.4 -

0.0

-0.4 —

-0.8

-

-

-

1 1 1

-

-

-

A\fV

( 1 USEC / DIVISION )

FREQUENCY SPECTRUM1.0

0.8 —

0.6 —

0.4 -

0 2

0.0

-

-

-

-

6

j

I

/

/

/

.

6dB

\

\\

.2V\\

..

V

1

(MHz)


- 5 8 -

WAVEFORMVERTICAL SENSITIVITY:HORIZONTAL RESOLUTION:

200 mv/div.50 us/div

L

JL.

Ar

——

—

/

\\

\

\\ \\\

\0 2 .5SPECTRUMVERTICAL: LINEAR FORMATHORIZONTAL: (MHZ)

5 . 0


- 5 9 -

SIGNAL WAVEFORM0.8

0.0

-0 .4 —

-0 .8

-

-

-

<

-

-

-

1\\l

A/ '

( .2 USEC / DIVISION )

1.0

0.8 -

0.6 -

0.4 -

0.2 -

0.00.0

FREQUENCY SPECTRUM

-

-

-

-

2.2

/r /J

I/

> // -/

'\\IdB

\j4.4

\

\

y5.0

(MHz)130


- 6 0 -


BOO mv/div.20 us/div

s

r

///

Y\\\

0 5 .0SPECTRUMVERTICAL: LINEAR FORMATHORIZONTAL: (MHZ)

10.0


- 6 1 -


200 mv/dlv.10 us/div

s

AI 1\

/I 111J

V

J

/

/

f\/T~

\\\

\\

\ \0 10.0SPECTRUMVERTICAL: LINEAR FORMATHORIZONTAL: (MHZ)

20.0


- 6 2 -

WAVEFORMVERTICAL SENSITIVITY: 200 mv/rlivHORIZONTAL RESOLUTION: • 1° u s / 1 i \

A A

A 1.1M

///

//

:

\\\V\

1

0 10.0SPECTRUMVERTICAL: LINEAR FORMATHORIZONTAL: (MHZ)

20.0

Figure 3-9. Signal waveform and frequency spectrum of the 10 MHz transducer.

- 6 3 -

mracnoN TABU

Figure 3-10. Drawing of the turn table.

Figure 3-11. Photograph of the turn table.

- 6 5 -

turn table 3\$\ sliding guided *!*13£- jig °fl

Turn tabled 3 3 £ r 500 mm °\5L IM^r^r ^?H1 A}°)^\ 7]$^ 200 mm

tabled 0.5

turn tabled i ^ ^ S-Er^ EJ-O|XJJ ^ E ^ ] s]«fl

scanner 5] z

5 turn

3.3. £

3-12 ^ H ^ 3-13

Westinghouse 14x14

MPE ^ ^ A

o] 10.6 mm < ]J1 ^ ^ ^ 0.6 mm

H.2%

4 4 1 MHz Sf 2.25 MHz

. Zircaloy-4 2 ) 4 ^ «e|-g- 7>^5] ^- *}6\7}

3-13

- 6 6 -

I

I» 03

1 -

-1 -

-2

liSllli I i

•Hil 11 N H|fffTfw

50}isec

• i

Time (

Figure 3-12. Backscattering echoes obtained from the fuel rod using the 1 MHztransducer.

I

20 40

Time(^s)60

Figure 3-13. Backscattering echoes obtained from the fuel rod using the 2.25 MHztransducer.

f n J | - FFT &6. 3-

14 3-15

So

A,

°1

BPE

14 , 1 MHz

2.25 MHz

0} n^i-

- 6 9 -

1.0 -

0.0

n=8 (1.035, 1.032)

n=9 (1.157, 1.156)

n=10 (1.284, 1.280)

n=11 (1.401, 1.402)

n=12 (1.523, 1.523)

n=13 (1.641, 1.642)

0.25 0.50 0.75 1.00 1.25Frequency (MHz)

1.50 1.75 2.00

Figure 3-14. Resonance spectrum of the cladding tube obtained using 1 MHz transducer.Here, n denotes the normal mode number. Left number in the parenthesis is resonancefrequency measured experimentally and right number is resonance frequency calculatedtheoretically.

1.0

0.8

<u

0.0

2.1

n=13 (2.705, 2.

2.4

n=14 (2.788, 2.780)

n=16 (2.954, 2.952)

2.7

Frequency (MHz)

3.0 3.3

5BFigure 3-15. Resonance spectrum of the cladding tube obtained using 2.25 MHztransducer. Here, n denotes the normal mode number. Left number in the parenthesis isresonance frequency measured experimentally and right number is resonance frequencycalculated theoretically.

4.1. MB

BBR *\4\ FFRDS(failed fuel rod detection system),[31] D]^- B&W(Bobcock and

Wilcox) 4 5 ] Echo330,[32] ANF(American Nuclear Fuel) *}$] Ultratest [33] %-°)

£ 2-3 mm) ^ L ^ S ^ e 7 r

) 100%

(Zircaloy-4/1-) ^ ^ 1 ^ ^ H H ^ ^

- 7 3 -

Receiver

Transmitter

Probe

Path of Ultrasonic Pulse

Fuel Rod

a) B & W Type

Transmitter

Fuel Rod

Receiver


b) BBR Type

Fuel Rod

Probe


c) ANF Type

Figure 4-1. Different vendors' probes of ultrasonic testing (quoted from Reference [2]).

-74-

Si71 nfl-g-o]cf.

FFRDS ^ ^

34.

o] 2:^.

i~2 ^isec

, 36]

BBR

FFRDS °fl^

3.7]

34.

O] 7 ^ ^ tfl7fl

- 7 5 -

30 S. zM-

330^: ^r^l^ i^g-4 ^151^ $3.^ #3^7}

^fi.^- ifl^-5] #21 ^ o H-cHl n -E). ^ A l ^ ^ ^ - ^ A}Jr^

717]- ^*>4. nl£) £ 3 3 ^ ^ 1 - ^'HM-^ 3713]

Echo330^r

. Ultratest °

71 fi] 9\^$\ ^ ^ 1 ^ 4 . Echo330^1M- Ultratest^ ^-

7fl -ofl xltj.. o]

wave)S

- 7 6 -

(So)

. So

MHz

^-4 -ffl S #1-71

3 MHz 4 dB ^ £ 2 1 «OU}

(A,)

a.-9-s.

4.2.

4-2 Sf a ^ 4-3^8: 4 4 711^3.

- 7 7 -

Ultrasonic strip sensor

Water \Fuel rods

Scanner

Flaw Detector

(Sonic 237)

AD

Waveform Digitizer

(Tek. RTD710A)

RS232C

GPIB

Computer

Controller Printer

Figure 4-2. Schematic diagram of the leak-defective fuel rod detection system

- 7 8 -

Figure 4-3. Overall view of the leak-defective fuel rod detection system: (a)scanner, (b) xy slide unit, (c) fuel assembly, (d) computer, (e) scannercontroller, (f) flaw detector, and (g) waveform digitizer.

- 7 9 -

^ 3(x, y,

z) ^ scanner, o] ^ # 3 } - ^ ^ - * } ^ ^ -g -4 H.S.«-1-

slide unit, ^L^Jl SLE]- ^ S

4.2.1. S ^

Staveley Instruments ^>^ Sonic 237 i - i - ^ ^ ^ 7 ] (flaw detector)!- ^

. °1 ^ ^ 1 ^ " dual voltage square wave pulser, RF display mode, dual flaw

gates ^--i: S.®*\JL &6.*\ RS232 1- -*fl

Pulser

Type Square wave

Pulse Amplitude Selectable 150 or 300 volts

Pulse Width 30 to 1,000 ns

Modes Pulse Echo, Dual, or Through Transmit

Receiver

Bandwidth 0.3 to 20 MHz (-3dB)

- 8 0 -

Gain

Display

Timebase

Pulse Repetition Rate

Delay Range

DualjGate

Gate Functions

Gate Start and Width

Analog Output

Oto lOOdB in 0.2dB steps

RF, Halfwave+, Halfwave-, Fullwave

150 Hz to 10 kHz in 50 Hz steps

-10 to 3,200 \is

Gate 1: peak detection and flaw alarm

Gate 2: peak detection and selectable thickness

or flaw alarm

0 to 3,200 us

0 to 5 volts full scale for 0 to 100% full screen

height signal.

Updated at the repetition rate.

4 *J J xJS.ui H P Id*L»L* -*— n -**r — - E - —

4-4

BNC

: 1.2 mm)

i , BNC Tfl ?)

- 8 1 -

Figure 4-4. Photograph of the ultrasonic probe.

- 8 2 -

4.3 ^ H *HI*1

4.23.

Metrotek A>^ C403 system^:

1.1 m(L)x0.6m(W)x0.5 m(H)

} ^ 3(x, y, z )# scanner 7} ^ ^ ^ t j - . ZL^ 4-5 °fl

l ^ slide unit oil # ^ 4 . °1 slide unit ^ z

scanner^ 2

-al- £SHf (x, y)

mm RS232

l fe slide unit

°1 (x, y)

4 - 6 ^ : slide unit £]

^ 0.05

7>o]

4.2.4.

Westinghouse 14x14

- 8 3 -

Figure 4-5. The ultrasonic probe mounted in the xy slide unit.

- 8 4 -

,1 „ Iw I,

I

8

©<D

l±JLd

0--~- 8

F i .j I j .

X-AX/S SMOKE 250

X-JX/S

m

IT-AXB SUDE UNIT

, . . i- — i—.

Figure 4-6. Drawing of the slide unit.

4.3.

4.3.1.

1.2 mm

mechanical damping factor 1- ^ ) ^ air backing *1 °fl JE.

^ ^ r c f l^^-^ : ^VJL, £;E<2}- »8-A].^O)| H I J E ^ ^ ^ lead

m e t a n i o b a t e 4 | ] ] § l l > ^ 4 l J ^ f ^ ^ ^ ^ ^ 4

Frequency : 3.0 MHz

Thickness: 0.5 mm

Acoustic impedance : 20.5x10^ kg/m^sec

- 8 6 -

LM Crystal(0.5 mm)

Backing Layer(0.5 mm)

Figure 4-7. Schematic diagram of the ultrasonic sensor designed for fuelassembly inspection.

- 8 7 -

°J A 4 (= sin"1 (CxICp)* 14.3°

.6 min)

1480 m/s o]5L Cp^ 3.0 MHz °1H A,

6000 m/s

. Air backing^: ^ l * f ^ i

0.2 mm -T^ I I^ aluminum foill-

air backing^

0.5 mm 7>

o]

"3! -i" Teknovit 3040^1 1/4

Acoustic impedance : 2.6x10^ kg/m^sec

Acoustic velocity : 2400 m/sec

Density: 1.1 g/m^

3.0 MHz ^ ^ - 4 ^ 1/4 4 ^ ^ : 0.2 mm

- 8 8 -

4.3.2.

impulse response

Impulse response ^ ^ ^ w l s . ^ UltraPac ^1^.^-i- 4-§-^>S^^. °1 A l ^

2\ ^ - § - 4 ^ ^ A i 7 ] ^ Accu-TronInc.^ Model 101OPR

4-8^: 4.3.1 ^ H ^ ^ ^ ^j^S] ^ i f -fr*W7l^ €>H housing

f. °1 housing^ 4^^

^•^•a 1.2 mm ^ . € ^ # strip ^

7} -g-olsl-SL^ o] housing^ t f l^e l^ 2^^ -S . ^3j-i|$jl4. vfl-?- ^B^-el^ 7V

slit 4 ^-^^r z | ^ ^^r^l tf^ldfc^H ^ ^ ^ ^ silver ribbon^ v)*H -§-

die

die $] ^fl^-cr ^• is^-T?!om-. ^ A i ^l2l'A] housing £•

- 8 9 -

0.3

2-00.6 0.6

Figure 4-8. Drawing of the ultrasonic sensor housing

- 9 0 -

°1 die

^ 3 3 8 mm, £°1 0.25 mm

0.2 mm

Micro-Coax Components,

0.58 mm °]JL 3.°}$] ^ j^^r 0.13 mm

^ ° f l , ^ l 3 1 ! ^ sensor housing 3) slit °fl

housing^ silver ribbon «>fl ^1 «B

Silver ribbon

•a-^i^-^- * H ^ ^ >floll"i- ^ l*>7l fl«fl A>-g- cf. n]^- California

Fine Wire Company 5] *flf-°-5. 3.7)^ 0.001 x 0.025 (mil) °}JL £5.^ 99.99%

Probe strip

-g-1- 4 ° l S . €%^1 ° 1 ^ 1 ^r 51^^- 0.5 mm ^ 1 ^ SUS plate

- 9 1 -

7. in L | VB

112 11 . 910

U r . AI11

T

109 ~ ^

3340

I

Figure 4-9. Drawing of the probe strip.

fixture 7} ^ . 1 ^ 2 S £M $1 cf

Strip holder

4-10 £ 1 S 1 i l l W ^ l *H4 £ ^ o l 4 . °1 * ^ , ^ 4-5

, slide unit°fl ^^"S]^ H S H i S ^ ^ l 'S-S.-g-i: ^}°}S.

. °] *C1 ^°fl^ *M) - ^^ 711 o]#3)- BNC

4.3.3.

. -g-

1) ^ u l ^ ^ r M " 5 ! impulse response -t #^^f^ ^4) ^4^r(3.0 MHz

2) \kn3--z: 2M- ^r-g-^M < tf^4i41- i l * l€ 3.7|(2 mm x 4

impulse reponse 4r 4^1

- 9 3 -

1EL

NO|P/NUIC

SSgSraB

™ ~ " - • —

*s*

MATERM. | Q'TY | SPEOTICWON j RCMARK

• u

U/T PROBE HOLDER

YL-KO2OO " " * ntOBEDO | "

Figure 4-10. Drawing of the probe strip holder.

3) °^±7\-S.t^ 0.2 mm ^ i ^ 3.7]$] aluminum foil •§•

4) i r u l € aluminum foil ^ -fre)^: ^ofl ^-JL H $)<=)) silver ribbon tfi°] 10

mm ^JE) #^-g- ^ H ^ t f . ^nfl, snVer ribbon °1 4*\ housing £] -f- ^

aluminum foil °fl tfl silver ribbon ^ $\ *) °ll -

5) 4 ^ 4)°fl>H § « 1 ^ aluminum foil 4 silver ribbon-§: ^ SJ-g- ^ tape S.,

] * } - ^ 7}#z}B\7} silver ribbon ^ ^ | aluminum foil 5] 71-^fel-i- 0.1

mm

6) 4 ^ 5) 1 1 4 1 - i - -n-^^r°flAi tfl^^^ aluminum foil

tape i ^

°fl#Al7> aluminum foil 4

air backing ^ 3 ° 1

7) # S l i * f 3 a)"^ ^ 7 1 - ^ ) - ^ ^ t a p e ^ . ^ . s H3^vfl

4 silver ribbon ^ -r" ^ ^ ^ - S . *}<$ impulse response 1r

8) ^ 4 ^ 1)~8)^- ^-^-*>^ air backing -g- aluminum foil 4 silver ribbon

9) ^o]7> 40 mm ^§£^1 ^1^1 - ^ ^ ?H^1- 2 7flt-

- 9 5 -

11)

housing^

housing •§- ^ J ^

îl^-R- die 3] ^°o> l-#^-7> ^ ^ housing^

die <H1 ^r^^l-71) # ^ ^JL, 4 ^ 1)~9H^ ^ w ] ^ ^ ^ ^ 4 1 " die

14) 4Ui housing ^^-°fl^1 ^ ^ ^ . 4 ^ 1 silver ribbon # ^ " 4 Âfl

2 4 ? } housing 4 3 # 3 * 1 # ^ < a i € ^r 9XS.^ ribbon 4 3.*}$

15) <y-#:fc*}fi] siver ribbon

silver ribbon 4

silver ribbon A

housing^ w>ôfl f- - ^-g.^- ^ i J E ^ # die

- 9 6 -

die

die

housing^

>H housing T2-^ -SMW silver paste

20) Teknovit 3040 ^ - ^ * ^^-ôfl ^ ^ # 4

housing Ml- -ofl 7rt.Vcf. ol

21)ol)S.A]7l- ^^ i* l ^ - ^ cf-g- ^ M ^ dieoflA^ t^)^ vflc}. ^ 1 ^ housing

tb ^ , impulse response

23) €>H housing^ slit -¥-fl ^^<^1 ^ 2mm ^ £ ^ ) ^ 'S- i - #

24) Siver ribbon 5] ^ #-^-^-ofl ^"^r =7fl ^^1 ^ , 10 mm

# 4 . 4 ^ 24)<Hl i n v # ^ ^1 ^-ig ^ ^ 5 . o] silver ribbon •§:

°1 Sa^- -¥-fl^- °J"^4iXH ^ o i ^-o} o j ^ « - ^ ^ ^Q^ housing^ slit

ofl fl^l^tj-. ^ ^ 4 i 4 5 | -2 .*!34 silver ribbon^: ^ 7 l « ? ] ^ ^ <?!^?!:4.

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#-8: ^lî housing 2] slit <Hl J\$\ ^ ^ ^ silver paste

- 9 7 -

25) Teknovit 3040 ^ - ^ *

housing vflofl &^r ##4:*1- ^ ^ ^ 71-3:4. ° H . S i ^ ^ 4 ^ 24) >H

, housing^

sand paper 3 . i ^ ^ i ^ T f l ^ ^ j - ^ A ^ ^JA^O] im p u i s e response

28) M ^ 4 BNC ^ol l-g- ^ S ^ ^C-H ^-oj^. ^ o] ^ d ifloJH n]Afl

BNC Tflol-g-g. 0^^3:4 o] <g^

- 9 8 -

#?*:•§• ^3) I ' l l (global matrix approaches *r*l3j- t\

^l (boundary matrix)"

o) «OV^ . 4 0 ^ ^ tfl«. ^ t - ^ -^ ^ ^ <?lS -oll tfl

*n ii(jn. n n vfl^si ^ 4 1 - ^ I ^ - ^ - f H tfltt i ^ "D^Dj^^o] zero.

frequency limits, cfl^l^^ ^°14. °1 $\*\}^ 4 ^ 4

o)

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frequency limit S . ^ 0} #>=. ^ H . ^ . .O] - ufl^ ^

- 9 9 -

£ 1

. O] X\ +

, i>a^ S.4°fl 2(x, y) ^ slide unit 4 turn table,

^l-ei -f-

^ . ^ § 1 - ^ monostatic pulse-echo (MPE)

bistatic pulse-echo (BPE) UO

V)^^- BPE turn

table

- 1 0 0 -

^ 3(X) y>

z) ^ slide unit, 3.^3. £.Ef

HiXTleft BLANK

A.

5 x 5

rf!3 =(2«2 -x r2 )y n (x i ) -2^ i K r t ' ( ^ ) ) rfI4 =2n[xTJn\xT)-Jn{xT)l

dl5 =2n[xTYn'(xT)-Yn(xT)], d2l =-xlHin1)'(xi),

d2i^xLJn'(xL), dn=xLYn'(xL), du=nJn(xT), d25=nYn(xT),

di2 =2n[Jn(xL)-xLJn'(xL)], di3 =2n[Yn{xL)-xLYn\xL)],

du=2xTJn'(xT) + [xT2 -2n2)Jn(xT), d35 =2xTYn'(xT) + [xT

2 -2n2]Yn(xT),

dn =(2n2 -yT2)Jn(yL)-2yLJn'(yL), dA3={2n2 -yT

2)Yn(yL)-2yLYn\yL),

d44 =2n[yTJn'(yT)-Jn(yT)], d45 =2n[yTYn\yT)- Yn(yT)],

d* -2n[Jn(yL)-yLJn'(yL)], d5i =2n[Ytt(yL)-yLYn'(yL)],

[yTz -2n2]Jn(yT), d55 =2yTYn<(yT) + [yT

2 -2n2]Yn(yT),

- 1 0 3 -

B. c« S2|- ZL

scattered

1st medium

P2

du dn dn du

d2l d22 d2i d24

*31 33

top

2nd layer

du =[2n2 -{yT2)

2\Jn{y^-2y$Jn'{yh

dn =[2n2 -(yT2)

2]Yn(y$)-2y2LYn'(y2

L)

du=2rHyT2Yn\y

T2)-Yn{yT

2)]

dn=2n[Yn(y2l)-y2

LYn'(y2L)]

dv=2yT2Jn'(y

T2)-[2n2 -{yT

2)2]Jn{yT

2)

34 =2ylYn'(yl)-[2n2 -(yT2)

2}Yn{yT2)

d22=y2Yn\yL

2)

-105-

dn dn dn dH

i\

i\

42

top

7th layer

d3l =

j )2 }Y(yj-{2n2 - (yj )2 }Yn(yj

- 1 0 6 -

dudn

dn

dn

dnd22

dndn

dud23

dll

dt3

dud*dudAA

bottom

yth layer

du=nYn(xJ)

=Yij[2xTjJn'{xT

j)-{2n2 -

- 1 0 7 -

d2X d22

top

mth layer

d22=yl,Jn\yTm)

TmJn'{yT

m)- Jn{yTm)}

43 =iim[2yTmJn'(y

Tm)-{2n2 -(yT

m

—P2

^ 71

xjT=yj'T(l-hj) (J=2,3,..,m-\)

y (/=2,3,...,/«)^ 4

-108-

Lame constant^

dn

i-l)th layer

dn={2n2 -{xTm_x

dn=2n[xTm_xJn\x

Tm_x)-

-2n2]JAxTm_x),

- 1 0 9 -

bottom

(m-l)th layer

du={2n2

du={2n2

diA =

"21 = Xm-

dn=2n[Yn{xLm-X)-xL

m_xYn'{xLm-X)l

d,3=2xTm_xJn'(x

Tm_x) + [(xT

m_x)2 -2n2]Jn(xLx),

d» =2xTm_xYn'(x

Tm_x) + [(xT

m_x)2 -2n2]Yn(x

Tm_x).

-110-

[".]•u

0

top

with layer d2l=-ymrn'(ym)

Kl-'31 *32

M3 U14

" 2 3 " 2 4

^ 3 3 ^ 3 4

bottom

(/-l)thlayer

du={2n2 -(xU)

du={2n2 -{xl,

dn=2n[xlxJn\xJ_x)-Jn{xU)\

d24=nYn(xlx).

d33 =2xJ_xJn'{

di4 =2xlxYn\

-2n2]Jn(xU),

-2n2\Yn{xlx).

- I l l -

"21

0

" 1 2

* 2 2

0

top

Ah fluid layer

—Pf-l

11 dn

"21 " 2 2

0 0

bottom

fth fluid layer

P/+1

Pi

- 1 1 2 -

^11 ^12 ^13 ^14

d2\ d22 d2l d2i

d3i dn da dMj

top

(/+l)th layer

dn={2n2 -(ylx

yix)2 -2n2}Jn(ylx)

J+x)2 -2n2]YM(ylx).

-113-

= m-\ %•*]

3x2 DflE^i

22

top

mth layer

du ={2n2 -{yTm)2Jn{y!;,)-2yL

mJn<{yLa),

dn=2n[yTmJn\y

Tm)-Jn{yT

m)l

n={2n2 -{yTm)2)Jn{yT

m)-2yTmJn\y

Tm).

- 1 1 4 -

Mi o | ^

9x9

={2n2 -{yT2)

2}JM)-2y^Jn\

dv=2r,[Yn(y2L)-y2

LYn'(y21)],

i5=2y2TYn'(y2

T) + [(y2T)2 -2n2]Yn{yT

2),

ds2 ="Jn(x2),

</21 =-*,#<'>'(*,),

u =nJn{xT2),

15i=nYn(x2L), dsl=-nYn{y$]

d59=-y^

- 1 1 5 -

d62 ={2n2 -(x2T)2}Jn(x2

L)-2x2LJn'(x2

L),

db,={2n2 -(x2T)2}Yn(x2

L)-2x2LYn'(x2

L),

dM=2n[x2TJn'(x2

T)-Jn(x2T)],

d65=2n[x2TYn'(x2

r)-Ytt(x2T)],

d69 = -(fi3/fi2 )2»D>3rYn\yl) - Yn(yl)l

d72=2n[x2LJn'(x2

L)-Jn(x2L)],

dn=2n[x2LYn'(x2

L)-Yn(x2L)],

dli={2n2 -{xT2)

2}Jn(xT

2)-2xlJn\xT

2),

d15={2n2 -{xT2)

2)Yn{xT2)-2xT

2Yn\xT

2),

d16 =-(ii3/ii2 )2n[y3L Jn • (y3

L) - Jn (y,L)],

= 2x\Jn'(x3L [(jc3

r )2 - 2n2 ]Jn (xt),

[(xl)2 -2n2]Yn(x3L),

d96=xlJn'(xiL),

dg7=x,LYn'(XiL),

d9S =

-116-

x}=k}aJt x]=k]Oj, y^-k^aj, yl,=kTJ+xaJ (,=1,2) o)

^(/=2,3)^ 4 * ^ Lame

constants

« i * (e,,«2,0,0,0,0,0,0,0)^.3.

4

I HiXT PAQI(S)!ef 18LANK

S"

1. J. T. A. Roberts, "Nuclear fuel NDE", The 3rd International Conference

Proceedings on the Nondestructive Evaluation in the Nuclear Industry(1980), pp.

23-45.

2. 3 $ i f , " C E ^ fS\<^S. A i « | i 7 | # £>*J", KAERI/EP-113/88 (1988), pp.

24, 66; "KWU 4 ^ 1 *%<&£- - H H 1 ^ 7 ] £ £ - ^ ", KAERI/IM-95/87 (1987), pp. 5.

3. M. S. Choi, M. S. Yang and H. C. Kim, "Detection of leak-defective fuel rods using

the circumferential Lamb waves excited by the resonance backscattering of

ultrasonic pulses", Ultrasonics 30, 221-223 (1992).

4. 3 M 34*1, "-S-4^

*1 ^ 074872 3. (1994).

5. 3 ^ ^ 2 ? 1 , «a-S-3|

# 7fl^",KAERI/RR-1545/94 (1995).

6. J. D. Murphy, J. George, A. Nagl and H. Uberall, "Isolation of the resonance

component in acoustic scattering from fluid-loaded elastic spherical shells", J.

Acoust. Soc. Am. 65, 368-373 (1979).

7. V. M. Ayres and G. C. Gaunaurd, "Acoustic resonance scattering by viscoelastic

objects", J. Acoust. Soc. Am. 81, 301-311 (1987).

8. N. D. Veksler, "Intermediate background in problems of sound waves scattering by

elastic shells", Acustica 76, 1-9 (1992).

- 1 1 9 -

9. M. F. Werby, "The acoustical background for a submerged elastic shell", J. Acoust.

Soc. Am. 90, 3279-3287 (1991).

10. G. C. Gaunaurd, "Hybrid background coefficients to isolate the resonance

spectrogram of submerged shells", J. Acoust. Soc. Am. 92, 1981-1984 (1992).

11. A. N. Norris and N. Vasudevan, "Acoustic wave scattering from thin shell

structures", J. Acoust. Soc. Am. 92, 3320-3336 (1992).

12. P. M. Morse and K. U. Ingard, Theoretical Acoustics (McGraw-Hill, Inc., New

York, 1968), pp. 425-426.

13. D. G. Crighton, A. D. Dowling, J. E. Ffowcs Williams, M. Heckl, and F. G.

Leppington, Modern Methods in Analytical Acoustics: Lecture Afote^Springer-

Verlag, New York, 1992), pp.510-523.

14. A. N. Norris and D. A. Rebinsky, "Acoustic coupling to membrane waves on

elastic shells," J. Acoust. Soc. Am. 95, 1809-1829 (1994).

15. X. Y. Huang, "Energy dissipation in sound scattering by a submerged cylindrical

shell," Acustica 77, 221-231 (1992).

16. L. W. Anson and R. C. Chivers, "Ultrasonic scattering from spherical shell

including viscous and thermal effects," J. Acoust. Soc. Am. 93, 1687-1699 (1993).

17. J. P. Lee, J. H. Song, and M. S. Choi, "The effects of material attenuation on

acoustic resonance scattering from cylindrical tubes, Ultrasonics 34, 737-745

(1996).

18. G.N. Watson, A Treatise on the Theory ofBessel Functions(Cambridge University

Press, London, 1966), 2nd ed., pp.199.

- 1 2 0 -

19. G.C. Gaunaurd and M.F. Werby, "Acoustic resonance scattering by submerged

elastic shells," Appl. Mech. Rev. 43, 171-208 (1990).

20. M. J. Lowe, "Matrix techniques for modeling ultrasonic waves in multilayered

media," IEEE Trans, on ultrasonics, ferroelectrics and freq. control, 42(4), 525-542

(1995).

21. C. Randall and F. E. Stanke, "Mathmatical model for internal ultrasonic inspection

of cylindrically layered structures," J. Acoust. Soc. Am. 83, 1295-1305 (1988).

22. W. T. Thomson, "Transmission of elastic waves through a stratified solid medium,"

J. Appl. Phys. 21, 89-93 (1950).

23. N. A. Haskell, "Dispersion of surface waves on multilayered media," Bull. Seism.

Soc. Am. 43, 17-34(1953)

24. L. Knopoff, "A matrix method for elastic wave problems," Bull. Seism. Soc. Am.

54,431-438(1964)

25. G. Maze, B. Taconet, and J. Ripoche, "Influence des ondes de "galeri a echo" sur la

diffusion d'une onde ultrasonore plane par un cy;indre," Physics Letters 84A, 309-

312(1981).

26. G. Maze, J. Ripoche, A. Derem, and J. L. Rousselot, "diffusion d'une onde

acoustique plane par des cylindres solides immerges: etude experimentale et theorie

des resonances," Austica 50, 39-50 (1982).

27. A. Derem, J. L. Rousselot, G. Maze, J. Ripoche, and A. Faure, "Diffusion d'une

onde ultrasonore par des tubes remplis d'air immerges dans I'eau," Austica 55, 69-

85(1984).

- 1 2 1 -

28. J. Ripoche, G. Maze, and J. L. Izbicki, " A new acoustic spectroscopy: resonance

spectroscopy by the MIIR," J. of NDE 5, 69-79 (1985).

29. G. Quentin, M. de Billey, and Hayman, "Comparison of backscattering of short

pulse by solid spheres and cylinders at large ka" J. Acoust. Soc. Am. 70, 870-878

(1981).

30. M. de Billey, "Determination of the resonance spectrum of elastic bodies via the

use of short pulse and Fourier transform theory," J. Acoust. Soc. Am. 79, 219-221

(1986).

31. F. D'Annucci and R. Scharpenberg, "Operational experience of ultrasonic testing on

fuel assemblies with FFRDS", Nuclear Europe .5, 23-24 (1985).

32. Bobcock and Wilcox, "Echo sounds out failed fuel", Nucl. Eng. Int. 31, 45-46

(1986).

33. T.R. Blair and L.F. Van Swam, "Looking for leaks with ultratest", Nucl. Eng. Int.

31,44-45(1986).

34. %%^ $\ 5*1, " 3 ^ 3 . 4 £ « l £ £ . ^ ^ l - f ^ H ^ " , KAERI/RR-638/87

(1987).

35. £ ^ « £ , % 1 ^ 2] 23 «?!,

T02 (1990).

36. # 3 1 3} 4<y,

1609/96 (1996).

", KRC-88N-

", KAERI/RR-

- 1 2 2 -

37. H. C. Kim, M. S. Choi and M. S. Yang, "Resonance scattering of acoustic waves

from circular cylindrical shell and circumferential wave propagation", J. Korean

Phys. Soc., Vol.22(1989), pp. 176-180

38. M. S. Choi, H. C. Kim and M. S. Yang, "Propagation characteristics of elastic

circumferential waves in nuclear fuel cladding tubes", Ultrasonics.30, 213-219

(1992).

- 1 2 3 -

INIS

KAERI/RR-1680/96

^ ^ -9(»1 Bj-^iS 7}7l#

1997. 2.

123 p. -B-(O), -¥-( ) 71 26 cm

«i

^ ^ ( s c a t t e r e d field)ofl>Hll (background)

^Di^A-s. ^(analogous)

i ^ P l ^ i ^ zero-frequency limits,

105]

1.2

Bibliographic Information SheetPerforming Org.

Report No.

KAERI/RR-1680/96

Title

Sponsoring Org.

Report No.Standard

Report NoIMS Subject

Code

Development of Nuclear Fuel Rod Inspection Technique UingUltrasonic Resonance Phenomenon

Project Manager

Researcher and Dep.

Pub. Place

Page

Note

Classified

Sponsor

Myoung-Seon Choi (NDE R&D Dept.)

Young-Sang Joo, Hyun-Kyu Jung, Yong-Moo Cheong(NDE R&D Dept.)

Taejon

123 p.

Pub. Org.

111. and tab.

KAERI

Yes(O), No( )

Pub. Date

Size

1997. 2

26 cm

1996 Research Project

Open(O), Outside( ), Class Report Type

Contract No.

Research Report

Abstract

The scattering of plane acoustic waves normally incident on a multilayeredcylindrical shell has been formulated using the global matrix approach And asimple way to fomulate the non-resonant background component in the fieldscattered by an empty elastic shell has been found. This is to replace thesurface admittance for the shell with the zero-frequency limit of the surfaceadmittance for the analogous fluid shelKi.e., the shear wave speed in the elasticshell is set to zero). It has been shown that the background thus obtained isexact and applicable to shells of arbitrary thickness and material makeup, andover all frequencies and mode numbers. This way has been also applied toobtain the expressions of the backgrounds for multilayered shells.

The resonant ultrasound spectroscopy system has been constructed tomeasure the resonance spectrum of a single fuel rod. The leak-defective fuelrod detection system of a laboratory scale has been also constructed. Prticularly,all techniques and processes necessary for manufacuring the ultrasonic probe ofthin (1.2 mm) strip type have been developed.

Keywords

resonance, scattering, fuel rod, multilayered shell, ultrasonic testing

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