Package for Machine Design

Finite Element Analysis in Structural Mechanics

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Edge heat transfer

Heat transfer at the edge of an element can be prescribed in the first load case, with the identifier T 1 through T 3, or in any subsequent load case, with the identifier T 11 through T 13. In the first case, the prescription applies to the entire process under consideration; in the other cases, only to the load case in which it was declared.

In the name.iB file, a vector is first defined using a LV set:

LV set number T 1/11 V $\alpha$ $T_o$ ; $\dot q=\alpha\left(T-T_o\right)$

or

LV set number T 2/12 V $c$ $T_o$ ; $\dot q=c\left(T^4-T_o^4\right)$

or

LV set number T 3/13 V $c_1$ $c_2$ $c_3$ $T_o$ ; $\dot q=c_1\left(T^{c_2}-T_o^{c_2}\right)^{c_3}$

and the set thus defined is then assigned to the edge of the selected elements:

AS load case number /$\dots$ /L set number E element number list L edge number /$\dots$

where

  • $T_o~[^\circ\text{C}]$ is the ambient temperature,
  • $\alpha~[\text{W}/\text{m}^2\text{K}]$ is the convective heat transfer coefficient,
  • $c~[\text{W}/\text{m}^2\text{K}^4]$ is the radiation constant,
  • $c_1~[\text{W}/\text{m}^2\text{K}^{c_2+c_3}]$ and $c_2,c_3~[1]$ are the constants of the general heat transfer law.

The dimensions of the quantities follow from the nonzero thickness of the semi-loof element (the edge has an area dimension). For edges and their local numbers, see the Reference Manual.

Note
The components of the vector can depend on the global coordinates $x,y,z$, using any of the available functional dependencies, see the Reference Manual.