Function
- Generate wave load parameters for static/dynamic analysis.
Call
From the main menu, select [Load] tab > [Type : Misc.] > [Etc.] group > [Wave Loads]
Input
Wave Load parameters dialog box
Enter new or additional wave load parameters.
Click Add.
Modify previously entered wave load parameters.
Select the relevant wave load parameter from the wave load list of the dialog box and click Modify.
When deleting previously entered wave load parameters.
Select the relevant wave load parameter from the wave load list of the dialog box and click Delete.
Display the defined wave load in graph format.
Click Total Wave Load....
Display the defined wave load in the table format.
Click Wave Load Data (Grid Form)....
Total Wave Load...
Display the defined wave load in graph format.
Total Load Parameter List dialog box
Wave Load Data (Grid Form)...
Display the defined wave load in the table format.
Wave Load Data(Grid Form) dialog box
Add/Modify Wave Load parameters dialog box
Generation Type
Generate wave loads based on the input wave information.
Static Load(Nodal Loads) : Wave loads are automatically converted into static nodal loads. Different static load cases are generated by Critical Positions.
Time History Load : Wave loads are automatically converted into time history loads.
In order to convert into time history loads, Time History Load Case must be defined in advance. Click ... button to generate Time History Load Case.
General Parameters
Vertical Coordinate : Select the global axis of vertical direction of the wave load. Horizontal direction is always applied as Global X-axis.
Water Weight Density
Water Depth : Water depth based on the mean sea level (M.S.L)
Mudline Elevation : Vertical level of mud line with respect to the mean sea level (M.S.L)
In the figure above, the left vertical axis is with respect to the mean sea level. The right vertical axis is with respect to the Mudline and will be used in the modeling. Wave loads are not applied to the elements located below mud line, or elements marked in gray in the figure above.
Wave Load Parameters
1. Drag & Inertia Coefficients
You can enter the form coefficients to calculate the drag force (Cd) and the inertia force (Cm).
Type
Constant : Apply the identical drag coefficient regardless of section diameter.
Linear Interpolation : Apply the drag coefficient by section diameters. The program performs linear interpolation for the diameters not specified in the table.
Drag & Inertia Coefficient
Diameter : The projected diameter of the member in the wave direction
Drag Coefficient Cd : Drag coefficient applied to the perpendicular direction of an element
Tangential Drag Coefficient Cdt : Drag coefficient applied to the tangential direction of an element
Inertia Coefficient Cm : Inertia coefficient applied to the perpendicular direction of an element
Tangential Inertia Coefficient Cmt : Inertia coefficient applied to the tangential direction of an element
Override Coefficients with Structure Group
Enter the drag and inertia coefficient by structure group.
2. Water Characteristics
Type : The available wave theories for consideration are as follows:
Airy Wave
Airy Wave (mean position)
Stokes V Wave
Stream Function w/ Current Effect
Stream Function w/o Current Effect
Cnoidal Wave
Solitary Wave
Function Order : Order of Stokes wave theory
Wave Direction : Wave load direction. Enter the degree from Global X-axis in counterclockwise direction.
Wave Height
Wave Length
Wave Period : Wave period and wave velocity through one wavelength.
Kinematics Factor : Factor considering irregular behavior of wave load. 0 ＜ Kinematics factor ≤ 1
Current Velocity
Surface(M.W.L) : Velocity of current at the mean water level (M.W.L)
Bottom : Velocity of current at the bottom of sea
Validation Check of Specifide Wave Theory : Validate the specified wave load data based on the wave theory.
3. Current Profile
Current loads will be generated by entering data in the Current Profile and will be included in the wave load cases. Note that these data will be neglected when "Stream Function with Current Effect" type is selected for the wave load type.
Direction : Refer to the figure below for wave direction.
Current Blockage Factor : Blockage factor of current due to structure
Elevation : 0 ≤ Elevation ≤ Depth of water(h)
Velocity : Velocity of current
4. Flood Condition
Select the member that is filled with seawater inside the cross-section. Pre-assign the corresponding member to a group and choose the group that represents the Flooded Member.
5. Marine Growth
Consider the variation in thickness of the structure due to marine growth.
Crest Position
Enter the Critical Position and Step for Wave Load calculation.
Critical Position : Generate nodal loads which will cause one of the following items depending on the position of crest.
Maximum Moment at Bottom
Minimum Moment at Bottom
Maximum Shear at Bottom
Minimum Shear at Bottom
Maximum Force Upward
Maximum Force Downward
Initial Position : Initial position/degree/time of wave load
Increase Step : Increment of crest position
Number of Positions : Number of positions to be calculated