PROPERTY LOADS

            

A FEMGEN load definition is made up of a load type (e.g. PRESSURE), an optional loadcase number, a geometric part to which the load is applied and some real number data to describe the load magnitude and possibly direction. The part to be loaded may be specified from the keyboard or selected with the cursor.

This load data is extrapolated to the finite element mesh associated with the FEMGEN part in a variety of ways depending upon the load type. For example FORCE loads are extrapolated to nodes, PRESSURES to element faces or edges, GRAVITY to element centroids.

It is important to note that a separate item of geometry must be located where the load is to be applied (unless a Load Mask is used) and that the magnitude of all loads is constant over the loaded part (except for HYDROSTATIC or where a Space Curve is used). The following command illustrates the simplest form of load definition; for more complex load definitions see section 2.14.5.1.

PROPERTY LOAD PRESSURE S1 100 0

 

Figure 2.108: Example Load

FEMGEN includes a number of default load types (listed below) in what is referred to as the NEUTRAL Environment. Other load types may be available if an analysis environment has been selected via the PROPERTY FE command. Where an analysis environment has been selected the Interface Program User guide for that analysis package should be consulted for definitions of the loads which appear in the FEMGEN menus.

In the FEMGEN NEUTRAL environment PROPERTY LOADS has the following sub-commands:

2.14.5.2 PROPERTY LOADS CENTRIFU - Define a centrifugal force load.

2.14.5.3 PROPERTY LOADS DEFINE - Used for model archiving purposes only; do not use.

2.14.5.4 PROPERTY LOADS DISPLACE - Define a prescribed displacement.

2.14.5.5 PROPERTY LOADS FORCE - Define a force load.

2.14.5.6 PROPERTY LOADS GRAVITY - Define a gravity load.

2.14.5.7 PROPERTY LOADS HEAT - Define a heat load.

2.14.5.8 PROPERTY LOADS HYDROSTA - Define a hydrostatic load.

2.14.5.9 PROPERTY LOADS PRESSURE - Define a distributed load.

2.14.5.10 PROPERTY LOADS TEMPERAT - Define a temperature load.

In some FEMGEN environments, a moving load type is available in FEMGEN when it has been included by the Interface Programmer in the selected analysis environment (refer to the Interface Program User guide). The load type name that appears in the FEMGEN menu is defined by the Interface Programmer and can be any name up to 8 characters, however the name 'TRUCK' is used here for reference purposes.

2.14.5.11 PROPERTY LOADS TRUCK - Define a moving load.