A New Medium-Speed Diesel Engine Series
J. Sato* (Niigata Engineering Co.,Ltd., Japan), K. Sonobe*, T. Sato*, H. Nagasawa**, D. Koishi**, H. Kido**, and Y. Sarai**
Environmental pollution such as global warming due to excessive CO2 emissions and IMO-directed NOx regulation are of worldwide concern. This paper introduces a series of advanced medium-speed marine engines developed with these environmental disruptions in mind. These engines feature increased maximum combustion pressure (Pmax), increased piston speed, longer stroke, to enhance specific fuel consumption (SFC) efficiency and smaller cylinder diameter, downsize engine dimensions, and increase engine output. In addition, these engines employ fire rings to reduce lubricating oil consumption (LOC). We verified through engine performance testing and actually deployment that running costs were reduced. To shorten the development time of this new series of engines and to cut the cost of their manufacture, we undertook a concurrent engineering approach and in-depth analysis of a database cataloguing past problems.
Key Words: Maximum Combustion Pressure, NOx, Valve Timing, Lubricating Oil Consumption, Fire Ring
We are the first producer of diesel engines in Japan. For our steady success and progress in this field we acknowledge the endorsement of our loyal customers, for whom we have long field experience and peripheral systems to meet their environmental and technical needs, and the needs of the times. IMO regulation on NOx emissions control with regard to diesel marine engines of output of 130 kW or more for new vessels built in and after January 2000, critical environmental disruption such as global warming due to CO2 emission, and incipient fossil-fuel depletion are all strong incentives for the development of new diesel engines with reduced NOx and CO2 emissions.
Further, there is an idea with the life cycle cost, which reduces quantity with the total energy to use by scrap from the manufacture of the engine. The engine builder must do the design to have considered that the life cycle cost reduces.
2. A NEW MEDIUM-SPEED DIESEL ENGINE SERIES
The new medium-speed engine series introduced in this paper, models 22HLX, 28HLX, and 34HLX, was developed on the basis of actual performance to data and on the test results and service experience under the important objective of production of environmentally-friendly engines.
This lineup of marine-vessel engines, consisting of three models for a total of 13 types, was designed with the objectives of maintaining, as far as possible, thermal efficiency, and of complying with IMO regulation values. Principal characteristics of the engines are tabulated in Table 1.