I am using FEniCs to apply a load on particular point of a square mesh. When checking people has proposed to use Pointwise but it seems to be a method to fix a displacement, others has proposed to use PointSource but this also is used for one component of a vector or I don’t how to use it correctly. …

values[0] is of the dimension of a scalar function space (print x to see this). This means that you are evaluating your function at a set of coordinates at once. This, if you want to control a specific value in this array, you need to identify which entry you would like to change (by inspecting x).

Hi, Hope you are ok. I am trying to solve a 3D (Orthotropic) linear elasticity in FEniCs but still getting an error message that I am not understanding very well. Code from ufl import * from dolfin import * import numpy as np import matplotlib.pyplot as plt #****************…

Hi, you cannot use the UFL inv operator to invert the 6x6 compliance matrix. As said in the corresponding doc, inv is implemented only for 2x2 or 3x3 since it uses a symbolic formula for the inversion. You must therefore either implement yourself the expression of C or go through numpy for instance …

Hi, I hope you are ok, I am trying to solve a linear elasticity problem. [Figure 2021-06-02 162139] But my objective is to assign different Young modulus to the different parts of the mesh above. For instance I want to assign E1 to the yellow part, E2 to the green part… Please can you show me t…

See for instance: [image] How to define different materials / importet 3D geometry (gmsh) Following Dolfinx discontinous expression , this code can be modified for the syntax in dolfin as follows: import dolfin mesh = dolfin.UnitCubeMesh(9, 9, 9) V = dolfin.FunctionSpac…

Sorry Dokken, I see my error Thanks

Hi, Thank you again for the help, I have now solved the problem of defining subdomains with different Young modulus. Now suppose I have a domain meshed with 3 node triangles like the figure below: [Figure 2021-06-03 114705] And I want to give two different Young modulus to triangles among the t…

You need to make a minimal example, as I have already linked you to how to make a discontinuous dolfin function that can store different material properties on each cell. Please follow the structure of the posts highlighted in Read before posting: How do I get my question answered? - #4 by nate

How to apply a load on a single point or a node

dokken June 2, 2021, 8:36pm 14

See for instance:

Or
https://fenicsproject.org/olddocs/dolfin/latest/python/demos/subdomains-poisson/documentation.html?highlight=subdomain

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How to apply a load on a single point or a node

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