Module: Force ()

Description:

This module computes the pressure force vector and the pressure moment vector generated on a surface or a set of surfaces of an object when this object is subject to a fluid flow. In numerical terms, the force is the integral of the product of the pressure and the surface area vector:

where (resp. ) and (resp. ) are the pressure and area vector (resp. at a face center). The pressure moment is the moment of the pressure force at the force origin C about the moment center P:

where is a face center.

The drag D, lift L and side force S can be computed with respect to one of the three main planes xy, yz or xz. For example, in the xy plane, provided the angle between the flow direction and the x direction:

where is the force vector.

Connections:

Data [required]
A 3D Unstructured Model.

Pressure [required]
A 3D Unstructured Model Field scalar field containing pressure values. If one and only one pressure field is found, it is suggested by default.

Ports:

Moment center

Coordinates of the moment center (see P in the above pressure moment formula).

Lift and drag computation

Enables or disables the computation of lift and drag.

Flow plane

Plane in which the drag and lift will be computed. This port is only displayed when Lift and drag computation is enabled.

Angle of attack

Angle in degrees between the flow direction and the x (resp. y, resp. z) direction when the flow plane is xy (resp. yz, resp. xz). This port is only displayed when Lift and drag computation is enabled.

Spreadsheet

The computation results are written in a spreadsheet. Choose append to append the existing spreadsheet, or new to open a new one.

Compute

Choose globally to get one result corresponding to the surface composed of all the selected boundaries. Choose per boundary to compute the result on each selected boundary.

Boundaries

Select the grid boundaries where the computation should be done.

Boundary types

Select the type of boundaries where the computation should be done. Effectively select/deselect all boundaries od specific type.