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Hi,

I have a cantilever, clamped at one end, 100 units long. It bends under its own weight (so, add a body load in the z direction of solid.rho*g_const).

Now, since this cantilever is bending downwards, the top surface will be stretched and will be longer than 100 units (like, 100.1 units or something) and the bottom will be shorter (like, 99.9 units or something). I need to calculate the length along the top surface of the cantilever. So the output number I desire is 100.1 or something.

To do this, I try: Model 1 > Definitions > Right click and add Integration > select the edge running down the side of the cantilever > Call it intop1. Solve the model and then collect the result under Results > Derived Value > Global Evaluation > Expression = intop1(1). I am integrating unity here so that I get the length in units of meters. Integral of 1 with respect to dx is just the length.

Now, I have tried this with Frame = Mesh, Geometry, Material, Spatial. None of them work. They all give me an answer of 100 rather than 100.1.

How do I integrate along the length of the DEFORMED cantilever?

I have attached a similar model in case you need to take a look. Though this model has a few extra things.

Thanks!

(Of course this is a simple example so you may say I should do it analytically - in fact the actual model is more complicated and there is no analytical solution. So COMSOL it is!)