In this lecture, we'll cover the following:

• Importing a pre-generated custom mesh into a finite element code.
• Defining support conditions using restrained nodes and degree-of-freedom masks.
• Constructing the global force vector from element contributions.
• Assembling the global stiffness matrix from element stiffness matrices.
• Applying boundary conditions and solving the system for nodal displacements.

In this lecture, we walk through the process of integrating a previously generated mesh into our own custom finite element code and preparing it for analysis. We begin by recreating the model setup, material properties, geometry and mesh, before defining support conditions through a set of restrained nodes. We then translate these supports into restrained degrees of freedom using a masking approach, ensuring that only the relevant vertical displacement constraints are enforced in line with the simplified degrees of freedom per node.

We then move on to assembling the global force vector by looping through each element, computing its equivalent nodal forces, and mapping these contributions into the correct global locations. A similar assembly process is followed for the global stiffness matrix, where each element’s stiffness contribution is computed and inserted using appropriate indexing. After constructing the full system, we apply boundary conditions by reducing both the stiffness matrix and force vector, and finally solve for nodal displacements. This completes the core finite element solution process, setting the stage for post-processing.

Next up

Next, we will compute and visualise the reaction forces from the custom analysis to verify equilibrium and assess the overall response.