Options for Excluding Hydrostatic Pressure from Fluid Loads Calculations

It is common in marine hydrodynamics simulations to calculate the thrust of a propulsion system on individual surfaces, such as the hull, propeller, or rudder. These thrust calculations are performed on open boundaries and are dependent on the chosen reference pressure or reference height. Hence, when the reference pressure or reference height is increased, the locally calculated forces also increases. Although this behavior is physically correct it complicates the comparison between different simulations or designs.

Pressure Option

This property lets you exclude the hydrostatic pressure in the following types of reports:

• Center of Loads
• Force
• Force Coefficient
• Moment
• Moment Coefficient

Pressure Option	Child Nodes and Properties
No Correction	Leaves hydrostatic calculations at their default.
Removes Hydrostatic Pressure based on Reference Height Removes a correction (subtracts the rho*g*h correction) from the force based on a reference height.	Reference Position Reference Position—specifies the reference position as a vector or as an expression. Reference Gravity Reference Gravity—obtains the value from the Gravity reference value node in the continuum. See "Reference Values" in Gravity Model Reference.
Removes Hydrostatic Pressure based on Generated Waves Removes a correction from the static pressure force based on the dynamic hydrostatic pressure of a VOF wave.	Reference Vof Wave Reference Vof Wave—obtains the value from your selected VOF wave. For more information, see Modeling VOF Waves. Reference Gravity Reference Gravity—obtains the value from the Gravity reference value node in the continuum. For more information, see "Reference Values" in Gravity Model Reference.
Removes Hydrostatic Pressure based on Nominal VOF Wave Removes a correction from the static pressure force based on the nominal hydrostatic pressure of a VOF wave.	Reference Vof Wave Reference Vof Wave—obtains the value from your selected VOF wave. For more information, see Modeling VOF Waves.
Difference in Hydrostatic Pressure between Generated Waves and Nominal VOF Wave Removes a correction from the dynamic hydrostatic pressure force of a VOF wave based on the nominal hydrostatic pressure of that VOF wave.	Reference Vof Wave Reference Vof Wave—obtains the value from your selected VOF wave. For more information, see Modeling VOF Waves. Reference Gravity Reference Gravity—obtains the value from the Gravity reference value node in the continuum. See "Reference Values" in Gravity Model Reference.
Provides Hydrostatic Pressure based on Reference Height Reports on a force correction based on a reference height.	Reference Position Reference Position—specifies the reference position as a vector or as an expression. Reference Gravity Reference Gravity—obtains the value from the Gravity reference value node in the continuum. See "Reference Values" in Gravity Model Reference.
Provides Hydrostatic Pressure based on Generated Waves Reports on a force correction based on the dynamic hydrostatic pressure force of a VOF wave.	Reference Vof Wave Reference Vof Wave—obtains the value from your selected VOF wave. For more information, see Modeling VOF Waves. Reference Gravity Reference Gravity—obtains the value from the Gravity reference value node in the continuum. See "Reference Values" in Gravity Model Reference.
Provides Hydrostatic Pressure based on Nominal VOF Wave Reports on a force correction based on the nominal hydrostatic pressure force of a VOF wave.	Reference Vof Wave Reference Vof Wave—obtains the value from your selected VOF wave. For more information, see Modeling VOF Waves.