# Generalized projective method to compute forces in the Import / Export data context

A new method called **Generalized projective method** to create force collections
is available in Flux 2021.2 in the Import / Export data context. This kind of
collection allows to compute forces on a generic mesh (i.e., a set of points) with
the aim to be exported to OptiStruct to setup a NVH analysis of electrical devices,
such as rotating machines. This method and then the collection created may be seen
as an extension of the **Simplified projective method dedicated to rotating
machines** previously named **Force collection dedicated to rotating
machine**.

**data supports**as it is shown in

**(b)**part of the figure below. The set of supports to integrate and compute magnetic pressure can be defined by an extruded compound path, a 2D grid as shown in

**(a)**part of the figure below or an extruded geometric line in an air region. All the components of the magnetic pressure are computed with the Maxwell tensor approach on the set of supports and finally they are projected on the support for the data collect.

Several applications for NVH analysis of axial flux motors, electrical machines with
no-cylindrical air gap or eccentricity studies are now possible. For more
informations about this new feature, see its dedicated documentation by typing in
the dedicated search engine of the Flux user guide the keyword: **Generalized
projective method**.

**Generalized projective method**in 3D it is now possible to compute axial forces while using a surrounding box composed of 2D grids (cylindrical and annular) around the moving part as show below:

**(a)**part of both figures above must be adapted to the device geometry to get accurate results.