BriefFiniteElementNet / BriefFiniteElement.Net

BriefFiniteElementDotNET (BFE.NET) is a library for linear-static Finite Element Method (FEM) analysis of solids and structures in .NET
https://www.bfe-framework.net
GNU Lesser General Public License v3.0
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GetExactInternalDisplacementAt #31

Closed peacelvirene closed 4 years ago

peacelvirene commented 4 years ago

The method GetExactInternalDisplacementAt is like this

        public Displacement GetExactInternalDisplacementAt(double xi)
        {
            throw new NotImplementedException();
        }
        #endregion

so it's still not done? and the GetInternalDisplacementAt is to get the dispacement by the Local CoordinationSystem?

Now I want to draw the dispacement of the structure, how can I get the dispacement?

epsi1on commented 4 years ago

Hi, You should be able to get internal displacement with method GetInternalDisplacementAt method and that is in local coordination system. To convert it to global one, use like this:

var xi = -0.5; //x = L/4
var disp = barElement.GetInternalDisplacementAt(xi);
var trMgr = barElement.GetTransformationManager();
var global = trMgr.TransformLocalToGlobal(disp);

the GetExactInternalDisplacementAt() is not simple enough to implement. Maybe be deleted next unless i be able to find a straightforward theory for using superposition principle for deflection of a beam under three type of load: uniform, concentrated and most general one nonuniform.I think the solution should be something like an numeric integral... not sure anyways...

peacelvirene commented 4 years ago

Thanks! I will.