4. Heat transfer

Having described the two main sources of heat - internal transfers between the gas and the walls, and friction - it's time to understand how these energy flows are dissipated.

The peak temperature of combustion gases in an internal combustion engine is around 2,500 K. The maximum permissible temperatures for materials, however, are much lower. In such cases, it is necessary to install cooling systems, particularly for the cylinder head, cylinder liners and pistons. In areas where the energy flux transmitted is very high, up to 10 MW/m ² , the thermomechanical stresses generated can lead to material fatigue (cracking), which is critical to the durability of mechanical parts. These phenomena are caused both by excessive temperature levels (above 400 ˚C for cast-iron parts and 300 ˚C for aluminum parts) and spatial thermal...