Automobiles powered by gasoline and Diesel engines are still sharing a large percentage of public and individual transport. Facing finite energy resources and pollution problems caused by cars implies an enormous challenge to improve internal combustion engines. To meet forthcoming exhaust gas legislation a thorough understanding of the complex in-cylinder processes is essential.
The optical diagnostic data provide complementary information to the traditional measurements (engine pressure, exhaust emission) and give invaluable insight for a better understanding of internal combustion engines. Moreover, they are often the only way to validate computed fluid dynamics (CFD) codes.