Abstract
The amount of the land transportation is limited due to the traffic congestion and environmental pollution in Japan.
In order to solve this problem, the way of the transportation is to be sifted from trucks to sea way.
To realize the change, high speed vessels with light and high efficient machinery are required. Especially for the main engine, it is required maximum power with minimum weight.
To cope with this requirement, the authors developed ultra high power, high speed diesel engine having the bore 320 mm, which is the largest high speed engine in the world.
Advanced technology including two-stage turbocharging and Miller systems in a field of large four-stroke diesel engine are adopted in order to achieve such ultra high power.
Finally, more than two times as high power as the conventional engine with the same bore could be achieved. (bmep = 2.89 MPa, mean piston speed =12.0 m/s, 700 kW/cyl, 1000 rpm.)
