Finite element space discretization

The thermal solver uses a Galerkin based finite element method [1] to discretize the governing heat conduction equation over an element in space.

where the temperature in each element is approximated using the element shape function ξj given by:

where:

  • m is the number of nodes in an element.
  • Tj(t) is the time-dependent temperature of nodes.

Applying the Gauss theorem and boundary conditions, where only Neumann boundary conditions are evaluated at ΩN, the conduction equation becomes:

where i and j are the nodes.

The previous equation can be expressed in a matrix form:

where the global mass matrix is:

the element stiffness matrix is defined as:

and the nodal loads vector is: