Verification of SubDyn and HydroDyn

Results Summery

Evan Gaertner

Case 1: MonopileDistributed Buoyancy

0 20 40 60 80-0.5

0

0.5

Time (s)

Buo

yanc

y F

orce

, X

(kN

/m) HydroDyn

0 20 40 60 80-0.5

0

0.5

Time (s)

Buo

yanc

y F

orce

, X

(kN

/m) Analytical

0 20 40 60 80-0.5

0

0.5

Time (s)

% D

iffer

ence

Z = -20

Z = -16

Z = -12Z = -8

Z = -4

Z = 0

0 20 40 60 80-0.5

0

0.5

Time (s)

Buo

yanc

y F

orce

, Y

(kN

/m) HydroDyn

0 20 40 60 80-0.5

0

0.5

Time (s)

Buo

yanc

y F

orce

, Y

(kN

/m) Analytical

0 20 40 60 80-0.5

0

0.5

Time (s)

% D

iffer

ence

Z = -20

Z = -16

Z = -12Z = -8

Z = -4

Z = 0

0 20 40 60 80-0.5

0

0.5

Time (s)

Buo

yanc

y F

orce

, Z

(kN

/m) HydroDyn

0 20 40 60 80-0.5

0

0.5

Time (s)

Buo

yanc

y F

orce

, Z

(kN

/m) Analytical

0 20 40 60 80-0.5

0

0.5

Time (s)

% D

iffer

ence

Z = -20

Z = -16

Z = -12Z = -8

Z = -4

Z = 0

Case 2: TripodBuoyancy

Distributed Buoyancy:

A) Horizontal (Member 45)

B) Vertical, Tapered (Member 46)

C) Angled (Member 20)

Tripod: Total BuoyancyFBx [N]

FBy [N]

FBz [N]

MBx [Nm]

MBy [Nm]

MBz [Nm]

HydroDyn -1.113E+02 2.930E-02 2.829E+06 -1.346E+00 7.741E+02 4.194E-02OTC: HydroDyn* 0 0 7.330E+06

OTC: STAR-CCM+* 0 0 7.460E+06

* Includes joint overlap

0 20 40 60 80-0.5

0

0.5

Time (s)

Buo

yanc

y F

orce

, Z

(kN

/m) HydroDyn

0 20 40 60 80

1.1372

1.1372

1.1372

1.1372

1.1373

x 104

Time (s)

Buo

yanc

y F

orce

, Z

(kN

/m) Analytical

0 5099.5

100

100.5

Time (s)

% D

iffer

ence

X = -6.201, Y = -10.74X = -9.9213, Y = -8.592

X = -13.6416, Y = -6.444

X = -17.3619, Y = -4.296

X = -21.0822, Y = -2.148X = -24.8025, Y = 0

0 20 40 60 80-0.5

0

0.5

Time (s)

Buo

yanc

y F

orce

, Z

(kN

/m) HydroDyn

0 20 40 60 80

1.762

1.764

1.766

1.768x 10

5

Time (s)

Buo

yanc

y F

orce

, Z

(kN

/m) Analytical

0 20 40 60 8099.5

100

100.5

Time (s)

% D

iffer

ence

Z = -34.7133Z = -34.2083

Z = -33.7033

Z = -33.1983

Z = -32.6933Z = -32.1883

Case 2: TripodDistributed Buoyancy

Horizontal Vertical, Tapered Angled

0 20 40 60 801.3768

1.3769

1.3769x 10

4

Time (s)

Buo

yanc

y F

orce

, Z

(kN

/m) HydroDyn

0 20 40 60 80

1.3773

1.3774

1.3774

1.3774

1.3774x 10

4

Time (s)

Buo

yanc

y F

orce

, Z

(kN

/m) Analytical

0 20 40 60 80

-0.4

-0.2

0

0.2

0.4

Time (s)

% D

iffer

ence

Z = -19.6538Z = -17.723

Z = -15.7923

Z = -13.8615

Z = -11.9308Z = -10

Case 3: JacketTotal Buoyancy

Jacket: Total BuoyancyFBx

[kN]FBy

[kN]FBz

[kN]MBx

[kNm]MBy

[kNm]MBz

[kNm]External 0 0 -1.96E+04 0 0 0Internal 0 0 -1.86E+04 0 0 0

Total 0 0 -3.81E+04 0 0 0Total

(H. SongNo Overlap)

0 0 3.88E+03

Hyd

roD

yn

Case 4: MonopileMorison LoadsCurrent: Linear velocity distribution from 0 to 2 m/s at MSL

0 20 40 60 80-0.5

0

0.5

Time (s)

Dyn

. P

ress

. F

orce

, X

(kN

/m)

HydroDyn

0 20 40 60 80-0.5

0

0.5

Time (s)

Dyn

. P

ress

. F

orce

, X

(kN

/m)

Analytical

0 20 40 60 80-0.5

0

0.5

Time (s)

% D

iffer

ence

Z = -20

Z = -16

Z = -12Z = -8

Z = -4

Z = 0

0 20 40 60 80-0.5

0

0.5

Time (s)

Iner

tial F

orce

, X

(kN

/m) HydroDyn

0 20 40 60 80-0.5

0

0.5

Time (s)

Iner

tial F

orce

, X

(kN

/m) Analytical

0 20 40 60 80-0.5

0

0.5

Time (s)

% D

iffer

ence

Z = -20

Z = -16

Z = -12Z = -8

Z = -4

Z = 0

0 20 40 60 80

0

2000

4000

6000

8000

Time (s)

Dra

g F

orce

, X

(K

N/m

)

HydroDyn

0 20 40 60 80

0

2000

4000

6000

8000

Time (s)

Dra

g F

orce

, X

(K

N/m

)

Analytical

0 20 40 60 80

0

2

4

6

x 10-6

Time (s)

% D

iffer

ence

Z = -20Z = -16

Z = -12

Z = -8

Z = -4Z = 0

Case 5: MonopileMorison LoadsRegular Waves: T = 10s, Hs = 6m

0 20 40 60 80-0.5

0

0.5

Time (s)

Dyn

. P

ress

. F

orce

, X

(kN

/m)

HydroDyn

0 20 40 60 80-0.5

0

0.5

Time (s)

Dyn

. P

ress

. F

orce

, X

(kN

/m)

Analytical

0 20 40 60 80-0.5

0

0.5

Time (s)

% D

iffer

ence

Z = -20

Z = -16

Z = -12Z = -8

Z = -4

Z = 0

0 20 40 60 80

-1000

0

1000

Time (s)

Dra

g F

orce

, X

(K

N/m

)

HydroDyn

0 20 40 60 80

-1000

0

1000

Time (s)

Dra

g F

orce

, X

(K

N/m

)

Analytical

0 20 40 60 80

-5

0

5

x 10-3

Time (s)

% D

iffer

ence

Z = -20Z = -16

Z = -12

Z = -8

Z = -4Z = 0

0 20 40 60 80

-2

0

2

x 104

Time (s)

Iner

tial F

orce

, X

(kN

/m) HydroDyn

0 20 40 60 80

-2

0

2

x 104

Time (s)

Iner

tial F

orce

, X

(kN

/m) Analytical

0 20 40 60 80-6

-4

-2

0

2

4x 10

-3

Time (s)

% D

iffer

ence

Z = -20Z = -16

Z = -12

Z = -8

Z = -4Z = 0

Case 6: MonopileMorison LoadsIrregular Waves: JONSWAP T = 10s, Hs = 8m

0 20 40 60 80-0.5

0

0.5

Time (s)

Dyn

. P

ress

. F

orce

, X

(kN

/m)

HydroDyn

0 20 40 60 80-0.5

0

0.5

Time (s)

Dyn

. P

ress

. F

orce

, X

(kN

/m)

Analytical

0 20 40 60 80-0.5

0

0.5

Time (s)

% D

iffer

ence

Z = -20

Z = -16

Z = -12Z = -8

Z = -4

Z = 0

0 20 40 60 80

-2

0

2

x 104

Time (s)

Dra

g F

orce

, X

(K

N/m

)

HydroDyn

0 20 40 60 80

-2

0

2

x 104

Time (s)

Dra

g F

orce

, X

(K

N/m

)

Analytical

0 20 40 60 80

-0.01

-0.005

0

0.005

0.01

Time (s)

% D

iffer

ence

Z = -20Z = -16

Z = -12

Z = -8

Z = -4Z = 0

0 20 40 60 80-4

-2

0

2

x 105

Time (s)

Iner

tial F

orce

, X

(kN

/m) HydroDyn

0 20 40 60 80-4

-2

0

2

x 105

Time (s)

Iner

tial F

orce

, X

(kN

/m) Analytical

0 20 40 60 80

-5

0

5

x 10-3

Time (s)

% D

iffer

ence

Z = -20Z = -16

Z = -12

Z = -8

Z = -4Z = 0

Case 7: Natural Frequencies Monopile

Ansys[Hz]

SubDyn[Hz] Difference

1 0.290 0.288 -0.80%2 0.290 0.288 -0.80%3 2.365 2.361 -0.17%4 2.365 2.361 -0.17%5 6.126 6.134 0.12%6 6.126 6.134 0.12%7 7.111 7.106 -0.07%8 11.487 11.414 -0.64%9 11.687 11.731 0.37%

10 11.687 11.731 0.37%11 19.051 19.450 2.10%12 19.051 19.450 2.10%13 23.034 23.394 1.56%14 26.823 27.240 1.56%15 27.385 29.941 9.33%16 27.385 29.941 9.33%17 34.881 36.123 3.56%18 36.023 41.244 14.49%19 36.023 41.244 14.49%20 45.211 46.649 3.18%

Tripod

Ansys[Hz]

SubDyn[Hz] Difference

1 0.321 0.323 0.62%2 0.321 0.323 0.62%3 2.649 2.750 3.82%4 2.649 2.750 3.82%5 3.883 4.045 4.17%6 3.883 4.045 4.17%7 3.897 4.060 4.16%8 3.915 4.078 4.17%9 3.915 4.078 4.17%

10 3.935 4.099 4.17%11 4.309 4.493 4.26%12 4.602 4.799 4.29%13 4.602 4.799 4.30%14 5.589 5.719 2.33%15 6.004 6.262 4.30%16 6.004 6.262 4.30%17 6.193 6.447 4.11%18 6.941 7.230 4.17%19 6.941 7.231 4.18%20 7.324 7.637 4.27%

Jacket

Ansys[Hz]

SubDyn[Hz] Difference

1 2.676 2.650 -0.98%2 2.676 2.650 -0.98%3 4.826 4.813 -0.27%4 5.281 5.205 -1.44%5 7.484 7.337 -1.97%6 7.484 7.337 -1.97%7 8.285 8.128 -1.89%8 8.582 8.585 0.04%9 9.018 9.030 0.13%

10 9.575 9.583 0.08%11 9.575 9.583 0.08%12 10.201 10.213 0.12%13 10.947 10.972 0.23%14 11.317 11.137 -1.59%15 11.680 11.705 0.21%16 11.684 11.705 0.18%17 11.768 11.794 0.22%18 11.929 11.881 -0.40%19 11.929 11.881 -0.40%20 11.983 12.005 0.18%

To Transition PieceTo Tower TopTo Tower Top

Natural Frequencies, TripodTripod

Old New

Ansys[Hz]

SubDyn[Hz] Difference SubDyn

[Hz] Difference

1 0.321 0.323 0.62% 0.323 0.62%2 0.321 0.323 0.62% 0.323 0.62%3 2.649 2.750 3.82% 2.750 3.82%4 2.649 2.750 3.82% 2.750 3.82%5 3.883 4.045 4.17% 4.045 4.17%6 3.883 4.045 4.17% 4.045 4.17%7 3.897 4.060 4.16% 4.060 4.16%8 3.915 4.078 4.17% 4.078 4.17%9 3.915 4.078 4.17% 4.078 4.17%

10 3.935 4.099 4.17% 4.099 4.17%11 4.309 4.493 4.26% 4.493 4.26%12 4.602 4.799 4.29% 4.799 4.29%13 4.602 4.799 4.30% 4.799 4.30%14 5.589 5.719 2.33% 5.719 2.33%15 6.004 6.262 4.30% 6.262 4.30%16 6.004 6.262 4.30% 6.262 4.30%17 6.193 6.447 4.11% 6.447 4.11%18 6.941 7.230 4.17% 7.230 4.17%19 6.941 7.231 4.18% 7.231 4.18%20 7.324 7.637 4.27% 7.637 4.27%

Case 8: Reaction Loads

Ansys[N]

SubDyn[N] Difference

Monopile 8.5610E+06 8.5577E+06 0.04%Tripod 1.4972E+07 1.4729E+07 1.62%Jacket 5.7942E+06 5.6957E+06 1.70%

Under Self Weight

OC4 Paper: Jacket Masses

Figure 2: HydroDynMass (t)

RNA 350TowerJacket 671.6243

OC4 Paper: Jacket Masses

Figure 3: HydroDynMass (t)

Hydrodynamic added mass to MSL -3,883.8Water mass in free flooded legs to MSL 183Growth mass 189.84