Thermal radiation is the emission of thermal energy from bodies due to their temperature. This energy is transferred as electromagnetic waves and is emitted by all bodies that have a temperature above absolute zero. Radiation is very significant at high temperatures as the amount of radiated power is proportional to the fourth power of the absolute temperature of bodies.
In SOLIDWORKS Simulation, radiation is defined by an emissivity of the surface and the ambient temperature of the surrounding environment.
In the below example, the bulb of the light assembly is made of glass and due to its temperature it radiates power to the surrounding bodies. A new simulation study is created and “thermal” simulation is selected from the type of analysis.
The radiation condition can be accessed from the “Thermal loads” menu.
Radiation command manager, the “surface to surface” or “surface to ambient” type of radiation can be selected. The “surface to surface” radiates the energy from one surface to other surfaces in the model. In the “surface to ambient” radiation usually there are no surfaces near the radiating surface. (as an example, the case of sun radiating at a car can be mentioned)
The “open system” option, accounts for the fact that some heat can be radiated directly to space rather than other surfaces in the model. This option needs to be unchecked for fully closed systems where all the radiated energy is transferred to the surfaces of the model.
In the next boxes the temperature of the radiating body and its emissivity needs to be entered.