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*WINDPOL,NAME = DIODORE_STRUCTURE_NAME

Data format:

One line comprising 4 values followed by an arbitrary number of line comprising 4 values each

XV YV ZV SURFV
ANGV(1) CXV(1) CYV(1) CMZV(1)
...
ANGV(n) CXV(n) CYV(n) CMZV(n)

Status :

Optional

Purpose :

To define the aerodynamic coefficients of the floating structure that yield wind forces.

Restriction :

The WINDPOL keyword must be associated with WIND to be taken into account

Details :

Parameter	Description
DIODORE_STRUCTURE_NAME	name of one of the mecanical structure in the hydrodynamic analysis with DIODORE : 8 characters maximum
without blank in the name
XV	x-Coordinates of the centre of the wind forces.
YV	y-Coordinates of the centre of the wind forces.
ZV	z-Coordinates of the centre of the wind forces.
SURFV	Reference Sv surface for computing forces
AINGV	Value of the incidence (in degrees).
CXV	Hydrodynamic coefficient CXVI along OX
CYV	Hydrodynamic coefficient CYVI along OY
CMZV	Hydrodynamic moment coefficient CMZVI around OZ

Note

Coefficients must be entered for increasing values of the angle of incidence between 0 and 360 degrees., The relation between coefficient and loads is the following \(F_{wind}=\frac{1}{2}\rho S_v C_d V^2\)

where \(C_d\) is a drag coefficient, \(S_v\) the effective (or projected) surface in the wind direction of the topsides. The relation with the \(CXV\) values to input and the \(C_d\) values is :

\(CXV = \frac{S_v C_d}{S_{ref}}\)
Where \(S_{ref}\) is the constant reference surface given as input. The sign of the \(CXV\) coefficient defines the direction of the loads. For example, a current heading of 180 degrees (negative x-axis) provides a current loads directed towards x negative axis. The \(CXV\) coefficient has to be negative;

Example :

*WINDPOL,NAME=FPSO
0.00 0. 10.10
1.00 0. 0.
45.00 1.14 1.14 0.2
90.00 0 -1 0.