## 3. Heated wire in black body enclosure

The test checks the 1D radiation overlay elements and demonstrates radiation capability of B2000++. A heated wire with surface temperature Ts is placed in a black body enclosure of temperature Tinf. The heat flux qs from the surface of the wire is then

qs = s e (Ts4 - Tinf4)

where s is the Boltzmann constant (5.6710-8 W/m2/K-4) and e the emissivity (here: 1.0), The wire material is copper (k=400 W/m) and the wire radius is 0.001 m.

A slice one element wide is modelled with axisymmetric heat conduction elements. Boundary conditions are:

• (1) Symmetry along the left and right side, which means 'free' edges, i.e. no ebc and nbc conditions applied.

• (2) T=Ts in the body. Setting along y=0 will propagate T=Ts through the body.

• (3) Radiation on the surface by applying radiation elements, see epatch 2 definition in the input file.

The test checks the heat flow qs through the wire surface of the wire against the above solution by extracting the heat flow field HEAT_RADCONV for the top element and comparing the values to the theoretical ones.