In this FDS example a simple radiator in a room is simulated.
1. Description
In a room with dimensions of 4 x 3 x 3 m, the radiator is simulated by modeling obstruction with a high surface temperature.

2. Mesh
The computational volume is divided into several meshes.
The meshes increase in definition as their proximity to the radiator increases.

&MESH ID='Grid 01', IJK=15, 15, 15, XB=0, 3, 0, 3, 0, 3/
&MESH ID='Grid 02', IJK=6, 30, 15, XB=3, 3.6, 0, 3, 0, 3/
&MESH ID='Grid 03', IJK=5, 60, 30, XB=4, 3.6, 0, 3, 0, 3/
3. Radiator
The radiator is simulated through different obstructions (OBST) which is assigned a surface (SURF) whose temperature is high. This is done via the TMP_FRONT command.
&OBST XB=3.8, 4, 1.8, 1.85, 0.2,1, COLOR= 'WHITE', SURF_ID='radiator' /
….
….
&OBST XB=3.8, 4, 1.9, 1.95, 0.2,1, COLOR= 'WHITE', SURF_ID='radiator' /
&SURF ID='radiator', TMP_FRONT=70. /
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4. Outputs
As outputs there are slice files that measure the speed and temperature of the air in the environment.
