Hi
Starting to use simulation for a shelf, and have a question about the external loads: what would be better to use,force, remote load, or distributed mass; the force seems to be more straightforward to understand (at least to me), same could be for distributed mass, whereas remote load is a bit more confusing.
Which one would you use for a simple shelf, imagine two brackets on which a straight piece is sitting (no bonding between them).
The load could be anything, i.e. books, or relatively heavy tools/objects.
Does the force mean that on each given point of the shelf there is such a load?
I am not an engineer so please be patient.
Thank you
Force will probably be what you want to use getting started.
If you apply a Force to a vertex (point) it will be a concentrated force. If you apply it to an edge it will be a force distributed along that edge. Most often you will probably want to apply a Force to a face, and when you apply to a face it gets distributed evenly along that face. The arrow symbols do a pretty good job representing it.
If the weight in real life is evenly distributed, then that's great. If however, you wanted to have a heavy object on the middle of the shelf, then you would want to represent that by applying the force only in that area.
You can do this by creating Split Lines (Features -> Curves -> Split Line) and using a sketch to split up the faces where you want to apply loadings. You can also create Splits right within the Force creation if you prefer. Alternatively you can use a "nonuniform" load distribution, but Split Lines are generally easier.
Here is an example where the same total force is applied to a smaller area to represent a heavy item placed in the middle of the shelf:
Remote Load is useful if you want to represent a weight or force application that is cantilevered off in space. It allows you to specify the location where that force/weight is centered and connects back to the faces you have selected with links.
See an example of remote load application here, representing the force being applied some distance off in space:
This is useful if you want to represent a bracket or some other component that would connect there, but isn't in your model. You have to be careful with remote loads as the links it uses to connect back may stiffen the model somewhat depending on your settings.
Anything that applies mass will also require gravity or some other acceleration to be turned on to produce force ( Force = mass * acceleration)
So if I apply a 100 lbf load, that should be equivalent to applying a 100 lb distributed mass and turning on gravity "load" (really an acceleration) with the default settings.
The benefit to using masses comes in if you ever need to vary the acceleration loading. For instance, shock tests may specify a 10 g (10 * gravity), 20 g, 50 g acceleration loading. They also have an effect in vibration / frequency studies.