Wave Characteristics Form

Additional form: Wave Data Table, User Wave Data

Use the Wave Characteristics form to define the characteristics of a wave. The appearance of the form changes depending on the Wave Type selected. The form has the following input options.

Wave Characteristic Name edit box. Use the default or specify a new name in this edit box for the wave characteristics definition
Wave Factors.
- Wave Kinematics Factor edit box. The wave kinematics factor accounts for wave directional spreading and irregularity in the wave profile shape that is not typically accounted for in two-dimensional wave kinematics. Typical wave kinematics factors range from 0.85 to 1.
- Storm Water Depth edit box. Storm depth is the depth measured from the storm water level to the mud line. The specified storm water depth is added to the specified mud line elevation to obtain the storm water level.
Wave Type. Choose to define the wave according to a published theory or define the wave yourself.
- From Selected Wave Theory option. When this option is selected for wave type, also specify any one of the following Wave Theory types to calculate the wave water particle velocities and accelerations:
- - Airy Wave Theory (Linear)
  - Stokes Wave Theory. Also specify the Order.
  - Cnoidal Wave Theory. Also specify the Order.
  - Wave Data options. This area of the form displays when From Selected Wave Theory is the Wave Type.
  - - Wave Height edit box. The wave height is distance from the wave trough to the top of the wave. The distance from the storm water level to the top of the wave is equal to half the wave height.
    - Wave Period edit box. The wave period is the period of the wave as seen by a stationary observer.

- User Defined option. When this option is selected for wave type, the wave is specified by defining a rectangular grid of points in a horizontal cut through the wave and then inputting the water particle velocity and acceleration at each point in the grid. The following areas appear on the form for a user defined wave type:
- - Number of Horiz. Points and Number of Vert Points edit boxes. Use these edit boxes to specify the number of horizontal and vertical points in the grid used to define the wave. After values have been entered in these edit boxes, fill in the horizontal grid line locations and the wave surface elevation (measured from the vertical reference datum; see Global Z Coordinate of Vertical Datum item on the Wave Load form) at each horizontal grid line in the Horizontal Coordinates and Surface Elevation spreadsheet. The horizontal grid locations should start at zero and proceed in ascending order to define a full wave length cycle. The horizontal grid lines typically are, but are not necessarily, equally spaced.

Similarly, fill in the vertical grid line locations (relative to the vertical reference datum; see Global Z Coordinate of Vertical Datum item on the Wave Load form) in the Vertical Coordinates spreadsheet. The vertical grid locations should start at the top of the wave and proceed in descending order to the mud line elevation. The vertical grid lines are typically more closely spaced near the top of the wave.

- - - Modify/Show Wave button. Click the Modify/Show Wave button to display the User Wave Data form. The number of horizontal and vertical points that display in the grid area of this form correspond to the Number of Horiz. Points and Number of Vert Points specified on the Wave Characteristics form.

Note: The User Wave Data form and the Wave Data Table form are essentially the same. The Wave Data Table form is accessed by clicking the Show Wave Table button on this form or on the Wave Plot form.

Choose a Display Option: All, At Horizontal Coordinate, or At Vertical Coordinate. Use the At Horizontal Coordinate and At Vertical Coordinate drop-down boxes to select the appropriate point. The grid area will update depending on the selection made.

In the grid, the Horiz Loc (Horizontal Location) and Vert from Datum (Vertical from Datum) columns are automatically filled. Fill in the Horiz Wave Vel (Horizontal Wave Velocity), Horiz Wave Acc (Horizontal Wave Acceleration), Vert Wave Vel (Vertical Wave Velocity) and Vert Wave Acc (Vertical Wave Acceleration) columns.

When entering data in the grid, enter zero if the considered point lies above the wave surface. The one exception to this rule is when the wave surface does not lie exactly at a specified grid vertical elevation. In that case, the velocities and accelerations at the wave surface are input at the point that lies immediately above the wave surface. It is understood by the program that these values apply at the wave surface, not at the grid location immediately above the wave surface.

Tip: When user waves are defined, it may be convenient to first define a wave from theory and then modify the resulting velocities and accelerations as desired. To do this, define the data for the wave from selected theory. Then, click the Show Wave Plot button or Show Wave Table button on the Wave Load form. This will cause the velocities and acceleration to be calculated based on the selected wave theory. Return to the Wave Load form and click the Modify button associated with the wave characteristics to redisplay the Wave Characteristics form. Then change the wave type to user defined and update the data as necessary.