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Wave LoaderPowered by the WAVE LOADS software developed byFluid Mechanics Institute, University of Hannover, Germany

This program is used to generate a wave load on a ROBOT structure model. The user enters waveparameters (a theory used to approximate wave kinematics, water depth, wave height, time period,etc.) and structure geometry (the geometry is imported from a ROBOT file). As a result, wave loadsare generated in a ROBOT project in the manner specified by the user (for the maximal effects only orfor each time step).Data: structure geometry (imported from the ROBOT file or the current program session) wave parameters (theory, dimensions, a simulation time, a time step, etc.)Results: wave load cases generated directly in the ROBOT project (separate load cases for the maximal

base shear and the maximal overturning moment or separate load cases for each time step)1. General interface

The whole interface is included within one module. The main menu (A) contains five items:1. Import model for model import options.2. Wave load parameters for detailed load parameters.3. Generation options for structure specific generation options.4. Drawing options for the graphical viewer (B) options.5. Generate to start load generation.

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There is also a data field in the worksheet (C), allowing edition of some of the general quantities like: awave theory, a transport model, water depth, a wave period or length, a current velocity and astructure rotation angle.The table (D) contains information concerning structure bars. Wave generation algorithms assume allthe bars to be tubes so the table contains the equivalent diameter column and the user editableincrease column enabling the user to change a value of the precalculated diameter. The table alsoallows edition of the following data for each bar: Cd (drag coefficient) and Cm (inertia coefficient),coefficients of Morissons formula, a number of subdivisions of a bar (forces generated are applied atthe points of subdivisions), a bar analysis flag (whether the bar is analysed or not). The following picture contains example of wave loads generated in a ROBOT model:

2. The model import dialog

This dialog lets the user choose the way a model should beimported. One can import the current ROBOT model or selecta file to import a model from.

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3. The wave load parameters dialog

In this dialog box the user may set up parameters concerninga wave model. The possible wave theories are: Airy wave theory (Stokes first order theory) Stokes second order theory Stokes third order theory Lagrangian formulation by Woltering Stokes fifth order theory Stream-function theory in formulation by Sobey Stream-function theory in formulation by Fenton Stream-function theory in formulation by DalrympleOther parameters like general ones (water depth, wave height,wave length/period, etc.) and more specific to the theories (anorder of stream function, a number of surface points for theapproximation of a wave profile, etc.) are also specified withinthe dialog.

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4. The generation options dialog

This dialog enables the user to set up some defaults andoptions for the loads to be generated inside a ROBOT model.First, as it is assumed that a wave direction is aligned with theglobal X axis, the user can specify the rotation angle of astructure. This way arbitrary configurations of the structure

with respect to the wave direction can be achieved. Fields concerning the number of subdivisions, the Cd and Cmcoefficients allow the user to set up defaults that will beapplied to all bars after an import.The user can also specify a way loads are generated insidethe ROBOT model. For now there are two possibilities ofdoing this. 1. One load case can be generated for each timestep2. Load cases can be generated for the maximal static effectsonly.To be able to calculate an overturning moment at least onemoment reduction point must be specified. This is the caseafter an import of any structure a default moment reduction

point is added automatically. The user can then add/deleteadditional moment reduction points (the overall number ofthem is restricted up to five).

5. The drawing options dialogThis dialog enables selection of several properties of the

graphical viewer. The user can enable/disable wave profileanimation, bars numbering, etc.