斜坡上非線性波浪傳動特性之研究 the characteristics of nonlinear wave transformation...

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斜坡上非線性波浪傳動特性之研究斜坡上非線性波浪傳動特性之研究

The Characteristics of Nonlinear Wave Transformation oThe Characteristics of Nonlinear Wave Transformation on Sloping Bottomsn Sloping Bottoms

Overall Project Duration: Month Overall Project Duration: Month AprilApril Year Year 20022002 – –

Month Month MarchMarch Year Year 20052005

((甲甲 -91-E-FA09-7-3)-91-E-FA09-7-3)

National Cheng Kung University

Overall Prospectus for Promoting University Academic Excellence of

Universities

卓越計畫卓越計畫 ----斜坡上非線性波浪傳動特性之研究斜坡上非線性波浪傳動特性之研究

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1.Research Manpower1.Research Manpower

• Chief Investigator• Prof. H. H. Hwung (黃煌煇 ) National Cheng-Kung University

• Co-Investigators• Prof. L. H. Huang (黃良雄 ) National Taiwan University• Prof. J. F. Lee (李兆芳 ) National Cheng-Kung University• Prof. C. P. Tsai (蔡清標 ) National Chung-Hsing University

• Foreign Consultants• Prof. Philip L-F. Liu Cornell University• Prof. Chan Eng Soon National University of Singapore


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• Research Staffs

• Students• Mr. H. C. Hsu (許弘莒 ) PhD student

• Mr. C. W. Zheng(鄭志維 ) PhD student

• Mr. Y. S. Lin (林宇銜 ) PhD student

• Ms. C. H. Lin (林均樺 ) M.S. student

• Mr. H. C. Zeng (曾鴻棋 ) M.S. student

• Mr. J. C. Huang(黃志誠 ) M.S. student

• Mr. K. C. Hu (胡凱程 ) M.S. student

• Ms. Y. X. Wu (吳怡荁 ) M.S. student

• Ms. C. W. Lee (李嘉文 ) M.S. student

• Mr. Y. P. Lee (李昱博 ) M.S. student

Dr. K. S. Hwang (黃國書 ) Associate Researcher

Dr. C. C. Liu (劉正琪 ) Associate Researcher

Dr. S. C. Hsiao (蕭士俊 ) Assistant Researcher

Mr. W. S. Chiang (江文山 ) Assistant Researcher

Mr. Y. H. Chang (張裕弦 ) Assistant Researcher


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2.Basic Information of the Project2.Basic Information of the Project

Overall Project Title: The Characteristics of Nonlinear Wave Transformation on Sloping Bottoms

Serial No.: 甲 -91-E-FA09-7-3Academic Affiliation: National Cheng Kung University

Serial No. Project TitlePrincipal

Investigator

TitleAcademic Affiliation

Overall Project

The characteristics of nonlinear wave

transformation on sloping bottoms

Hwung-Hweng Hwung

Professor


Sub-Project 1

Nonlinear modulation of progressive waves

Hwung-Hweng Hwung

Professor


Sub-Project 2

The transmission of wave envelopes

Hwung-Hweng Hwung

Professor


Liang-Hsiung Huang

Professor

National Taiwan University

Sub-Project 3

The generation of infragravity waves

Jaw-Fang Lee

Professor


Sub-Project 4

The studies on wave breaking and related flow

fields

Hwung-Hweng Hwung

Professor


Ching-Piao Tsai

Professor

National Chung Hsing University


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3.Overall Prospectus3.Overall Prospectus The dynamics of nonlinear wave interaction in the ocean

are really complicated, interesting and attractive phenome-n

on. Especially, the wave modulation that includes the move

ments of chasing, composing, splitting and evolving among

waves have been investigated by a lot of researchers since

1960.

A number of experimental studies, although far less in co

mparison with those of theoretical studies in quantity, were

afterward conducted by Benjamin and Feir(1967), Lake et al.

(1977), Ramamonjiariso and Mollo- Christensen(1979), Mel

ville(1982), Su et al.(1982),


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Bonmarin and Ramamonjiarisoa(1985), Blien et al.(1986). Tulin

and Waseda(1999) and Westhuis(2001). Fruitful results have be

en accomplished with these studies.

However, most of them used shorter wave lengths, normally l

ess than 1.0 m, or conducted under a single frequency and with

un-seeded wave board motion for the facilities limits. Therefore,

the mechanisms of wave modulation are not fully understood. R

eferring to the description above, the transformation of wave pro

pagation, nonlinear wave interaction, wave modulation and the d

ynamics after wave breaking as well as the related flow field are

deserved to offer more researches on this issues.


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Thus in the three- year integrated project, the general prop

osal is suggested according to the following four Themes:

(1) Nonlinear modulation of progressive wave

(2) The transmission of wave envelopes

(3) The generation of infragravity waves

(4) The studies on wave breaking and related flow fields

The scope of the proposed research may be broadly divid

ed into two complementary components: one is on the enha

ncement of numerical methodologies in simlulating the


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generation and transformation of wave envelopes as well

as the breaking process from wave steepening to turbule

nt mixing, and the other is on the experimental study of t

he same process at a sufficiently large scale. In order to

obtain the completeness with systematical results, seven

teen sub- projects have been planned as following:


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1) Measurements on surface elevation and interior flow field of the wave modulation in uniform water depth

2) Measurements on surface elevation and interior flow field of the wave envelopes in uniform water depth

3) Measurements on the highest wave and the related flow field after wave breaking in uniform water depth

4) Measurements on the characteristics of wave modulation on sloping bottoms

5) Measurements on the characteristics of wave envelopes on sloping bottoms

6) The generation of infragravity waves

7) Energy transmission of infragravity waves

8) Measurements on the interior flow field of infragravity waves

9) The measurements of wave breaking on sloping bottoms


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10) The measurements of the related flow field after breaking on sloping bottoms

11) The analysis on parameters indices of wave nonlinearity

12) The interaction between waves and structures on sloping bottoms

13) Wave models for regular and irregular wave in uniform water depth

14) Model for regular wave on sloping bottoms

15) Model for irregular wave on sloping bottoms

16) Breaking wave model for regular wave on sloping bottoms

17) Breaking wave model for irregular wave on sloping bottoms


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Scope of Research

MeasurementOn surface elevation and interior flow field

Model(13) (14) (15)

(16) (17)

Sloping bottoms(4) (5) (9)

(10) (11) (12)

Uniform water depth(1) (2) (3)

Infragravity waves

(6) (7) (8)


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4.Annual Prospectus for year 20024.Annual Prospectus for year 2002 In order to understand the principal characteristics of

nonlinear wave transformation, four sub- projects have been carried out in the first year, they are:

(1) Measurements on surface elevation and interior flow field of the wave modulation in uniform water depth.

(2) Measurements on surface elevation and interior flow field of the wave envelopes in uniform water depth.

(3) Measurements on the highest wave and the related flow field after wave breaking in uniform water depth.

(4) Wave models for regular and irregular wave in uniform water depth.


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5. Annual Performance for year 20025. Annual Performance for year 2002• 5.1Facilities : Super Tank

47 m 238 m

m

Wave

generator

Wave

generator

Wav

e ab

sorb

erW

ave

abso

rber

300 m

5 m

47 m 238 m

5.2

m

Wave

generator

Wave

generator

Wav

e ab

sorb

erW

ave

abso

rber

300 m

5 m

Wave generator design water depth : 2.5~3.5 m

optimal period : 1~13.5 sec design maximum wave height : 1 m

drive system : servo-hydraulic


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InstrumentationsInstrumentations

• Wave gage

– capacitance-type, designed and manufactured

by THL

– Resolution:12 bits on a dynamic range of 4.5 m.

– Linearity: 0.5%

– distributed at 66 stations, each gage was

mounted at 40 cm away from the sidewall.


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InstrumentationsInstrumentations• Velocimeter

– acoustic Doppler velocimeter (ADV) × 1• SonTek YSI 10-MHz ADV

– three-components velocity measurement– sampling volume less than 0.2 cm3 – accuracy: 1% of measured range – velocity range: 1 mm/s to 2.5 m/s

– electromagnetic (EM) current meters × 8• ALEC ACM250-A

– two- components velocity measurement– sampling volume =5 mm – accuracy: 2% of measured range – velocity range: 25 cm/s to 2.5 m/s


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5-2 Facilities Examination:5-2 Facilities Examination:

• The key factors to well model the long time evolution of nonlinear wavetrains depend strongly on the scale of wave flume, the capability of wave generator, the instrumentation and data analysis. Therefore, to ensure the capabilities of the facilities was necessary before the elaborate tests.


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Wave Generator Regular wave condition Case: Reg19F , T=1.6 sec

0 1 2 3 4 5freq u en cy ( H z )

1 E -0 0 61 E -0 0 50 .0 0 0 1

0 .0 0 10 .0 1

0 .11

PS

D (

m2 se

c )

2 3 0 0 2 3 0 5 2 3 1 0 2 3 1 5 2 3 2 0 2 3 2 5 2 3 3 0 2 3 3 5 2 3 4 0tim e (s ec)

-0 .1 0

-0 .0 5

0 .0 0

0 .0 5

0 .1 0

S (m)

d isp lacem en t o f w av e b o ard

0 1 2 3 4 5freq u en cy ( H z )

1 E -0 0 6

1 E -0 0 5

0 .0 0 0 1

0 .0 0 1

0 .0 1

0 .1

ampl

itude

( m

)

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Experimental Conditions of Experimental Conditions of Regular WaveRegular Wave

Depth of waterDepth of water

dd == 2.5 m , 3.5 m2.5 m , 3.5 m

Period Period TT == 1.1 ~3.0 sec1.1 ~3.0 sec

Wave steepnessWave steepness

kaka00 == 0.05~0.400.05~0.40 0 0 .4 0 .8 1 .2 1 .6

d /L 0

0

0 .1

0 .2

0 .3

0 .4

0 .5

k a 0

d = 2 .5 md = 3 .5 m


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Regular wave Case:Reg19F

0 5 1 0 1 5 2 0 2 5 3 0

-0 .2

0

0 .2

(m)

2 0 2 5 3 0 3 5 4 0 4 5 5 0

-0 .2

0

0 .2

(m)

1 0 1 5 2 0 2 5 3 0 3 5 4 0tim e ( sec )

-0 .1

0

0 .1

S ( m )

th eo re tica l v a lu e

g au g e : ch 1 , x = 1 5 m

d isp lacem en t o f w av e_ b o a rd


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4

1

2

2

)sin()sin()sin(

0

22220

kkkk

bbaa

tbtbta

c

c

c

cc

Experimental Conditions of Experimental Conditions of SeededSeeded Waves System

c

ak

ˆ

00

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Experimental Conditions of Experimental Conditions of SeededSeeded Waves System

Depth of water =Depth of water =3.5 m3.5 m

Period Period =1.3 , 1.6 , 2.0 sec=1.3 , 1.6 , 2.0 sec

Wave steepness Wave steepness kaka= = 0.08~0.230.08~0.23

Side band amplitudeSide band amplitude 0.05 , 0.1 , 0.3

Side band frequency Side band frequency parameterparameter 0.1~2.2

0/ ab

0 .4 0 .6 0 .8 1 1 .2 1 .4

d /L 0

0 .0 5

0 .1

0 .1 5

0 .2

0 .2 5

0 .3

k a 0

d = 3 .5 m


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Seeded Waves System Case:T63F

0 5 1 0 1 5 2 0 2 5 3 0 3 5 4 0

-0 .2

0

0 .2

(m)

2 0 2 5 3 0 3 5 4 0 4 5 5 0 5 5 6 0

-0 .2

0

0 .2

(m)

1 0 1 5 2 0 2 5 3 0 3 5 4 0 4 5 5 0tim e ( sec )

-0 .1

0

0 .1

S ( m )

in p u t d a ta

g au g e : ch 1 , x = 1 5 m



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Experimental Conditions of Experimental Conditions of TwoTwo Waves System

2202

1101

21

2

2

2

2

coscos2

T

dtTT

T

dtTT

ttH

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Experimental Conditions ofExperimental Conditions ofTwoTwo Waves System

Depth of waterDepth of water

dd == 3.5 m3.5 m

Period Period TT == 1.4, 1.6, 2.0 sec1.4, 1.6, 2.0 sec

dtdt == 0.1~0.4 sec0.1~0.4 sec

Wave steepnessWave steepnessHH == 0.05~0.30 m0.05~0.30 m

KaKa00 == 0.10~0.250.10~0.25 0 .4 0 .6 0 .8 1 1 .2

d /L 0

0 .0 8

0 .1 2

0 .1 6

0 .2

0 .2 4

0 .2 8

k a 0

d = 3 .5 m


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Two Waves System Case:B1163F

0 5 1 0 1 5 2 0 2 5 3 0 3 5 4 0 4 5 5 0 5 5 6 0

-0 .2

0

0 .2

(m)

2 0 2 5 3 0 3 5 4 0 4 5 5 0 5 5 6 0 6 5 7 0 7 5 8 0

-0 .2

0

0 .2

(m)

2 0 2 5 3 0 3 5 4 0 4 5 5 0 5 5 6 0 6 5 7 0 7 5 8 0tim e ( sec )

-0 .1

0

0 .1

S ( m )

in p u t d a ta

g au g e : ch 1 , x = 1 5 m

d isp lace m en t o f w av e_ b o a rd


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Experimental Conditions of Experimental Conditions of Wave Packet Wave Packet

Depth of water d =3.5 m

Period T =1.2, 1.3, 1.6 sec

Wave amplitude a =0.045~0.1 m

2

2

( ) exp( ( / 5 ) )sin( ), 16 16 , 2 /

( ) exp( ( / 3 ) )sin( ), 16 16 , 2 /

t a t T t T t T T

t a t T t T t T T


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Wave Packet Case:P07F1

0 2 0 4 0 6 0 8 0 1 0 0

-0 .1

0

0 .1

(m)

0 2 0 4 0 6 0 8 0 1 0 0

-0 .1

0

0 .1

(m)

0 2 0 4 0 6 0 8 0 1 0 0tim e ( sec )

-0 .0 5

0

0 .0 5

S ( m )

in p u t d a ta

g au g e : ch 1 , x = 1 5 m



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5-3 Results5-3 Results(ka0=0.1207)


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(a) t=30 sec

(b) t=130 sec

(c) t=300 sec

(d) t=2000 sec

Contour of wave amplitude in log scale for wave ka0=0.2038


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2300 2320 2340 2360 2380 2400tim e, sec

R E G 19F 1L on g tim e an d space evo lu tion o f w ave pro file

-0 .2

0 .0

0 .2

surf

ace

elev

atio

n(m

)

ch : 1 x = 1 5 m

ch : 1 6 x = 9 1 m

ch : 2 0 x = 1 0 6 m

ch : 3 0 x = 1 3 6 m

ch : 4 2 x = 1 7 2 m

ch : 5 0 x = 1 9 6 m

ch : 5 8 x = 2 2 0 m


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xox ebb

~


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ka0=0.1386


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ka0=0.118


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ka0=0.1538


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Experimental condition(reg04)Experimental condition(reg04)

– Wave height : 0.1552+/- 0.0018 m– Wave period : 1.597 +/- 0.0056 sec– Still water depth : 3.5 m– Wave steepness : ka=0.1207 (3rd order)– Relative depth : d/L=0.8667


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Experimental condition(reg28)Experimental condition(reg28)

– Wave height : 0.179+/- 0.003 m (1.67%)– Wave period : 1.597 +/- 0.0038 sec (0.24%)– Still water depth : 3.5 m– Wave steepness : ka=0.1386 (3rd order)– Relative depth : d/L=0.86


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0 0 .1 0 .2 0 .3 0 .4k a o

0

0 .1

0 .2

0 .3

0 .4

0 .5ka

ma

x

d / L = 0 .5 1~ 1 .5 4break in g

n o n -b reak in g

u n sa tu ra ted


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Ka=0.1118


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Ka=0.1258


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Ka=0.1651


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Ka=0.2515


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100.0 120.0 140.0 160.0 180.0time (sec)

-0.3

0.0

0.3

-0.4

-0.2

0.0

0.2

0.4

u z/h=-0.27

z/h=-0.43

z/h=-0.64

velocity record compared with the linear random wave theorykaka00=0.15, =0.15, ff00=0.5, =0.5, bb±±/a/a00=0.3=0.3

Yellow – measured

White – computed


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1-D Bicromatic Sine Waves Over Uniform Water Depth1-D Bicromatic Sine Waves Over Uniform Water Depth(B39)(B39)

• Wave Conditions: (Water Depth = 3.5m)– Wave Height = 0.15m (H_in/2H = 0.02143) , – Wave Period = 1.80 sec , Wavelength = 5.04

3m (kh = 4.3487, ka = 0.09318)– Wave Period = 2.20 sec , Wavelength = 7.04

9m (kh = 2.9268, ka = 0.06271)


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1-D Bicromatic Sine Waves Over Uniform Water Depth(B39) - 1-D Bicromatic Sine Waves Over Uniform Water Depth(B39) - 2-Layer Model2-Layer Model


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1-D Bicromatic Sine Waves Over Uniform Water Depth(B39) - 1-D Bicromatic Sine Waves Over Uniform Water Depth(B39) - 3-Layer Model3-Layer Model


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Experimental condition(b47)Experimental condition(b47)

– Wave height : 0.15 m– T1: 1.90 sec– T2: 2.10 sec– Still water depth : 3.5 m


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6. Publications for year 20026. Publications for year 20021) H.H. Hwung(2002): Experiments on Nonlinear Wave Tr

ansformation and Wave Modulation. Proceeding of the 24th Ocean Engineering Conference in Taiwan, pp78-84. (in Chinese)

2) P.Lynett, P.L.F.Liu, H.H.Hwung and W.S.Chiang(2003): Multi-Layer Modeling of Wave Groups from Deep to Shallow Water. Proceedings of OMAE 2003 pp1-8

3) H.H. Hwung, W.S.Chiang, P.L.F.Liu and P.Lynett(2003): Sideband Evolution of Initially Uniform Deep Water Wave. (Submitted to I.C.C.E)

4) W.S. Chiang, H.H. Hwung and Y.H. Chang(2003): Experiments on the Front of Uniform Wave Train in a Super Tank. (Submitted to I.C.C.E)


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5) P. Lynett, P.L.F.Liu and H.H.Hwung(2003): A Multi-Layer Approach to Boussinesq- type Modeling. (Submitted to I.C.C.E)

6) H.C. Hsu , Y.Y. Chen and H.H. Hwung(2003): Surface Wave Evolution in Water of Varying Depth. (Submitted to I.C.C.E)

7) W.S. Chiang, H.H. Hwung, Y.H. Chang and K.C. Hu(2003): Evolution of Transient Wave Front. (Submitted to Journal of Coastal and Ocean Engineering) (in Chinese)

8) H.H. Hwung, K.S. Hwang, H.H.Chen, Y.H.Chang and K.J. Hwung(2003): Velocity Measurements in Modulated Side-Bands. (accepted by the 25th Ocean Engineering Conference in Taiwan, October 2003) (in Chinese)


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9) W.S. Chiang, H.H. Hwung, Y.H. Chang and K.C. Hu(2003): Evolution of Transient Wave Front. (accepted by the 25th Ocean Engineering Conference in Taiwan 2003) (in Chinese)

10) H.H.Hwung and W.S.Chiang(2003): Wave Modulation in Uniform Water Depth. (Keynote lecture in the 27th National Conference on Theoretical and Applied Mechanics, November,2003)

11) S.C. Hsiao, C.C. Liu and H.H. Hwung(2003): Numerical Simulation of Nonlinear Waves over a Uniform Water Depth by Multi-Layer Approach. (Preparing and will be submitted to International Journal of Numerical Methods in Fluids)


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12) H.H. Hwung, K.S.Hwang and C.P. Tsai(2003): Measure-ments and Predictions on the Internal Flow Fields of Modulated Waves. (Preparing and will be submitted to J. Waterway Port, Coastal and Ocean Engineering)

13) H.H. Hwung, W.S. Chiang and P.L.F. Liu(2003): Experiments on Wave Modulation in Deep Water. (preparing and will be submitted to Journal of Fluid Mechanics)

14) H.H. Hwung, W.S. Chiang and L.H. Hwang(2003): The Growth of Wave Modulation in Deep Water. (preparing and will be submitted to Physics in Fluids)

斜坡上非線性波浪傳動特性之研究 the characteristics of nonlinear wave transformation...

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