Soot limit
The soot limit , even smoke limit, ( English soot limit or black smoke limit ) is a parameter for the operation of diesel engines . It describes the point in the stoichiometric fuel ratio curve from which the amount of fuel supplied is greater than that of the oxygen required for combustion . If this is the case, the mixture is said to be too “rich” . In this respect, the requirement applies to let the engine work with a "lean" mixture in order to prevent the unburned fuel from being deposited as soot on the inner wall of the combustion chamber . This deposit, especially on the piston and the cylinder running surface , leads to long-term engine damage . Modern diesel engines are designed in such a way that they reach the soot limit at a combustion air ratio ( lambda ) = 1.3. Externally, the exceeding of the soot limit is noticeable due to the significantly blacker exhaust gas compared to normal operation .
See also
literature
- Klaus Mollenhauer, Helmut Tschöke (Ed.): Manual Diesel Engines . Springer, Berlin a. a. 2007, ISBN 978-3-540-72164-2 .
- Yvan Gauthier: Injection pressure in modern passenger car diesel engines: Influence on soot emissions . Vieweg + Teubner, Wiesbaden 2009, ISBN 978-3-8348-0936-0 .