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Primitive Shapes and Mesh Densities

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The following presents the results for the primitive shapes at mesh densities between 0.5 and 1.0.  The shapes were also compared to analytic results for sinkage levels of +/- 1.0 meter at a mesh density of 0.7.

 

2.1 Cube Results

 

The cube is 10 meters in length with its vertical center on the horizontal construction plane.

 

Table 2.1.1 Cube Mesh Density 0.5-0.7 Results

 

Table 2.1.2 Cube Mesh Density 0.8-1.0 Results

 

 

Model Sinkage       = -1.0m

Water Density 1025.9 kg/m^3

Mesh Density 0.7

% Error

Analytic

Orca3D

Displaced Volume

400.000

m^3

400

m^3

0.000

VCB

-3.000

m

-3.000

m

0.000

Area Moment of Inertia

833.333

m^4

833.3

m^4

0.004

Waterplane Area

100.000

m^2

100.00

m^2

0.000

Immersed Area

40.000

m^2

40.0

m^2

0.000

Wetted Surface

260.000

m^2

260.00

m^2

0.000

Wetted Girth

18.000

m

18.00

m

0.000

BM

2.083

m

2.083

m

0.016

Table 2.1.3 Cube Negative Sinkage Results

 

Model Sinkage       = 1.0m

Water Density 1025.9 kg/m^3

Mesh Density 0.7

% Error

Analytic

Orca3D

Displaced Volume

600.000

m^3

600

m^3

0.000

VCB

-2.000

m

-2.000

m

0.000

Area Moment of Inertia

833.333

m^4

833.3

m^4

0.004

Waterplane Area

100.000

m^2

100.00

m^2

0.000

Immersed Area

60.000

m^2

60.0

m^2

0.000

Wetted Surface

340.000

m^2

340.00

m^2

0.000

Wetted Girth

22.000

m

22.00

m

0.000

BM

1.389

m

1.389

m

0.008

Table 2.1.4 Cube Positive Sinkage Results

 

2.2 Sphere Results

 

The sphere is 10 meters in diameter with its center on the horizontal construction plane.

 

Table 2.2.1 Sphere Mesh Density 0.5-0.7 Results

 

Table 2.2.2 Sphere Mesh Density 0.8-1.0 Results

 

Model Sinkage       = -1.0m

Water Density 1025.9 kg/m^3

Mesh Density 0.7

% Error

Analytic

Orca3D

Displaced Volume

184.307

m^3

181.4

m^3

1.577

VCB

-2.455

m

-2.454

m

0.022

Area Moment of Inertia

452.389

m^4

451.6

m^4

0.174

Waterplane Area

75.398

m^2

75.33

m^2

0.090

Immersed Area

29.337

m^2

29.3

m^2

0.126

Wetted Surface

125.664

m^2

125.59

m^2

0.059

Wetted Girth

13.694

m

13.69

m

0.032

BM

2.455

m

2.453

m

0.063

Table 2.2.3 Sphere Negative Sinkage Results

 

 

Model Sinkage       = 1.0m

Water Density 1025.9 kg/m^3

Mesh Density 0.7

% Error

Analytic

Orca3D

Displaced Volume

339.292

m^3

339

m^3

0.086

VCB

-1.333

m

-1.333

m

0.025

Area Moment of Inertia

452.389

m^4

451.7

m^4

0.152

Waterplane Area

75.398

m^2

75.34

m^2

0.077

Immersed Area

49.203

m^2

49.2

m^2

0.006

Wetted Surface

188.496

m^2

188.41

m^2

0.045

Wetted Girth

17.722

m

17.72

m

0.009

BM

1.333

m

1.333

m

0.025

Table 2.2.4 Sphere Positive Sinkage Results

 

2.3Vertical Cylinder Results

 

The vertical cylinder is 8 meters in diameter and 12 meters in length.  The horizontal construction plane intersects the cylinder so that is has a 4 meter draft at 0 sinkage.

 

Table 2.3.1 Vertical Cylinder Mesh Density 0.5-0.7 Results

 

Table 2.3.2 Vertical Cylinder Mesh Density 0.8-1.0 Results

 

 

Model Sinkage       = -1.0m

Water Density 1025.9 kg/m^3

Mesh Density 0.7

% Error

Analytic

Orca3D

Displaced Volume

150.796

m^3

150.6

m^3

0.130

VCB

-2.500

m

-2.500

m

0.000

Area Moment of Inertia

201.062

m^4

200.4

m^4

0.329

Waterplane Area

50.265

m^2

50.18

m^2

0.170

Immersed Area

24.000

m^2

24.0

m^2

0.000

Wetted Surface

125.664

m^2

125.55

m^2

0.090

Wetted Girth

14.000

m

14.00

m

0.000

BM

1.333

m

1.331

m

0.175

Table 2.3.3 Vertical Cylinder Negative Sinkage Results

 

 

Model Sinkage       = 1.0m

Water Density 1025.9 kg/m^3

Mesh Density 0.7

% Error

Analytic

Orca3D

Displaced Volume

251.327

m^3

250.9

m^3

0.170

VCB

-1.500

m

-1.500

m

0.000

Area Moment of Inertia

201.062

m^4

200.4

m^4

0.329

Waterplane Area

50.265

m^2

50.18

m^2

0.170

Immersed Area

40.000

m^2

40.0

m^2

0.000

Wetted Surface

175.929

m^2

175.80

m^2

0.073

Wetted Girth

18.000

m

18.00

m

0.000

BM

0.800

m

0.799

m

0.125

Table 2.3.4 Vertical Cylinder Positive Sinkage Results

 

2.4Cone Results

 

The cone has a base diameter of 7 meters and a height of 7 meters.  The cone is orientated tip down and the horizontal construction plane intersects giving it a draft of 5 meters with 0 sinkage.

 

Table 2.4.1 Cone Mesh Density 0.5-0.7 Results

 

Table 2.4.2 Cone Mesh Density 0.8-1.0 Results

 

Model Sinkage       = -1.0m

Water Density 1025.9 kg/m^3

Mesh Density 0.7

% Error

Analytic

Orca3D

Displaced Volume

16.755

m^3

16.7

m^3

0.329

VCB

-2.000

m

-2.000

m

0.000

Area Moment of Inertia

12.566

m^4

12.5

m^4

0.528

Waterplane Area

12.566

m^2

12.55

m^2

0.130

Immersed Area

8.000

m^2

8.0

m^2

0.000

Wetted Surface

28.099

m^2

28.08

m^2

0.069

Wetted Girth

8.944

m

8.94

m

0.048

BM

0.750

m

0.749

m

0.133

Table 2.4.3 Cone Negative Sinkage Results

 

 

Model Sinkage       = 1.0m

Water Density 1025.9 kg/m^3

Mesh Density 0.7

% Error

Analytic

Orca3D

Displaced Volume

56.549

m^3

56.5

m^3

0.086

VCB

-0.500

m

-0.500

m

0.000

Area Moment of Inertia

63.617

m^4

63.4

m^4

0.341

Waterplane Area

28.274

m^2

28.23

m^2

0.157

Immersed Area

18.000

m^2

18.0

m^2

0.000

Wetted Surface

63.223

m^2

63.18

m^2

0.069

Wetted Girth

13.416

m

13.42

m

0.027

BM

1.125

m

1.123

m

0.178

Table 2.4.4 Cone Positive Sinkage Results

 

2.5Horizontal Cylinder Results

 

The horizontal cylinder has a 6 meter diameter and a 10 meter length.  It is orientated on its side with the horizontal construction plane intersecting it giving a 3 meter draft with 0 sinkage.

 

 

Table 2.5.1 Horizontal Cylinder Mesh Density 0.5-0.7 Results

 

 

Table 2.5.2 Horizontal Cylinder Mesh Density 0.8-1.0 Results

 

 

Model Sinkage       = -1.0m

Water Density 1025.9 kg/m^3

Mesh Density 0.7

% Error

Analytic

Orca3D

Displaced Volume

82.502

m^3

82.3

m^3

0.245

VCB

-1.828

m

-1.827

m

0.078

Transverse Area Moment of Inertia

150.849

m^4

150.3

m^4

0.364

Longitudinal Area Moment of Inertia

471.405

m^4

470.9

m^4

0.107

Waterplane Area

56.569

m^2

56.50

m^2

0.121

Immersed Area

8.250

m^2

8.2

m^2

0.609

Wetted Surface

90.358

m^2

90.27

m^2

0.097

Wetted Girth

7.386

m

7.39

m

0.057

BMT

1.8284

m

1.826

m

0.133

BML

5.7139

m

5.719

m

0.090

Table 2.5.3 Horizontal Cylinder Negative Sinkage Results

 

 

Model Sinkage       = 1.0m

Water Density 1025.9 kg/m^3

Mesh Density 0.7

% Error

Analytic

Orca3D

Displaced Volume

200.241

m^3

200

m^3

0.120

VCB

-0.753

m

-0.752

m

0.178

Transverse Area Moment of Inertia

150.849

m^4

150.3

m^4

0.364

Longitudinal Area Moment of Inertia

471.405

m^4

470.9

m^4

0.107

Waterplane Area

56.569

m^2

56.50

m^2

0.121

Immersed Area

20.024

m^2

20.0

m^2

0.120

Wetted Surface

154.686

m^2

154.61

m^2

0.049

Wetted Girth

11.464

m

11.46

m

0.033

BMT

0.7533

m

0.752

m

0.178

BML

2.3542

m

2.355

m

0.035

Table 2.5.4 Horizontal Cylinder Positive Sinkage Results