Middle speed diesel engine (EcoDiesel SAVETEN) was developed in order to achieve very low fuel consumption and meet the IMO NOx regulation. Generally, the fuel consumption and smoke generation should be increased when NOx emission is reduced. This also means that the production of CO2 (a so-called green house gas) will increase. This is one of the most difficult subjects on engine development. But EcoDiesel SAVETEN has realized“lower fuel consumption”and“lower NOx emissions”at the same time, without causing a increase in smoke emission.
We thought out a new combustion concept for lower fuel consumption without increasing maximum cylinder pressure and injection pressure by using a simplified cyclic simulation. In order to realize the new combustion concept, the newly designed fuel injection system, combustion chamber and intake&exhaust system were applied. This com-bustion system is called the ASSIGN (Available Space Scattering Injection Geometric Nexus) combustion system. This realized the 10g/kWh lower fuel consumption than the conventional engines on the equivalent NOx emissions. And this is applied to the marine auxiliary diesel engines from 360kW to 3500kW.This is one of the YANMAR' s solutions for the marine environmental protection.
