Creation of sub-element conductance

The elemental conductance, Gi , for a sub-element i is computed as:

where:

  • k is the thermal conductivity.
  • L is the characteristic length, which is determined as follows depending on the element type:
    • For a beam element, it is the distance from the element center to the ends.
    • For a shell element, it is the length of the perpendicular line going from the element center to an element's edge.
    • For a solid element, it is the length of the perpendicular line going from the element center to a side surface.

    The thermal solver computes a negative value for L when the element center falls outside the sub-element. For example, in an obtuse triangle, the conductance between edge li and the element center is negative.

  • A is the characteristic area, which is determined as follows depending on the element type:
    • For a beam element, it is the specified cross-sectional area.
    • For a shell element, the area of each edge is given by the shell thickness times the edge length.
    • For a solid element, it is the area of each side surface.