8.1.8. Moonpool Pressure from a Hydrodynamic Diffraction Analysis

Click the   icon to add a Moonpool Pressure object to the Static Structural analysis.

Alternatively, follow these steps:

  1. Right-click the Static Structural analysis.

  2. Select Insert > Moonpool Pressure from the context menu.


Note:  A Moonpool Pressure object may only be added after a Hydrodynamic Pressure object has been added to the Static Structural analysis. Ensure that the number of Moonpool Pressure objects in the Static Structural analysis is the same as the number of Moonpools defined in the upstream Hydrodynamic Diffraction analysis.


8.1.8.1. Configuring the Moonpool Pressure Object

Configure options for the Moonpool Pressure object in the Details panel:

Figure 8.20: Details of Moonpool Pressure

Details of Moonpool Pressure

The Activity field sets the suppression state of the Moonpool Pressure object. Set it to Suppressed to exclude the object from the analysis.

8.1.8.1.1. Scope: Moonpool

Use Scope: Moonpool to select the surfaces to map moonpool hydrodynamic pressures onto. Surfaces are selected either by Named Selection, or by Geometry Selection from the Graphical window.

8.1.8.1.2. Moonpool Details

After selecting the moonpool surfaces in the Static Structural model, you must associate them with the corresponding Moonpool in the Hydrodynamic Diffraction analysis. Moonpool Name in HD Analysis lists the names of the Moonpools that are defined in the Hydrodynamic Diffraction analysis, which are associated with the structure selected in the Hydrodynamic Pressure object. Select the appropriate Moonpool from this list.

The Number of Pressure Modes defined in the Hydrodynamic Diffraction analysis for the selected Moonpool is displayed for reference.

8.1.8.1.3. Displayed Pressures

In some instances, the Moonpool Pressures shown in the Graphical window may be out of date. In this case, the Refresh Graphical Window option will appear, in an invalid state, and should be changed from Required to Not Required. The option will then disappear, and the state of the Moonpool Pressure object will change to show that it requires an update. Right-click the Moonpool Pressure object, and select Generate to display the correct Moonpool Pressures.

8.1.8.1.4. Imported Moonpool Pressures

After generating the Moonpool Pressure object, the Minimum and Maximum Moonpool Pressures on diffracting panel elements are reported. Where applicable, values are displayed for the wave case and phase angle selected in Display for Wave Case and Display Pressures/Accelerations At Phase Angle, respectively, as defined in the associated Hydrodynamic Pressure object.

8.1.8.2. Generating Moonpool Pressures

Once the Moonpool Pressure object is configured, right-click it and select Generate to start the pressure transfer process. The following parameters for the pressure transfer process are copied from the Hydrodynamic Pressure object:

  • Wave Case Definition

  • Wave Frequency/Period

  • Wave Direction

  • Incident Wave Amplitude

  • Wave Position

  • Specified Phase Angle or Number of Phase Increments

  • Include Hydrostatic Pressure

The output data files from the Hydrodynamic Diffraction calculation are read to determine the moonpool hydrodynamic pressures at the structural mesh nodes for the requested wave case(s).


Note:  The Hydrodynamic Pressure Add-on takes into account any difference in the unit systems that are employed in the Hydrodynamic Diffraction and Static Structural systems.


The transferred pressures are displayed in the Graphical window, and can be compared to the Moonpool Pressures shown in the Pressures and Motions result object in the upstream Hydrodynamic Diffraction system. The pressure Component Selection may need to be matched to those included in the Hydrodynamic Pressure object for such a comparison to be made.