Ansys Learning Forum Forums Discuss Simulation 3D Design Applying volumetric force at each node Reply To: Applying volumetric force at each node

NickFL
Subscriber

Sorry for the late reply. I have a broken elbow, so I am typing like a rooster.

And sorry, again, for recommending pressure (surface force) when you clearly had a volumetric force in the title. Instead of having forces, you will have a force per volume (such as N/mm³). This is typically used in Emag simulations. When you create the csv with the appropriate units, there will be the option to use the applied imported load as a body force density (or volume force density-I cannot recall the terminology Mechanical uses). There can be a force density in each component direction. This was added in a recent version of ANSYS, so if you are using an old unsupported version I recommend you upgrade.

To understand why you need a force density and not just the forces, consider the following thought experiment. If you have a linear cube element, and you applied 1 [N] at each node, you would have 8 [N] acting on that element. If we use a finer mesh, so two elements in each direction, we then end up having 27 nodes and therefore 27 [N] applied. We are solving a different problem! By using the force density, the smaller element size will shrink the applied force on each node. ANSYS is great in that it keeps all the bookkeeping hidden from us. That is why we pay the big bucks for the software--not to have to consider such things.

What physical process are you modeling to have these external forces?