Textos de Apoio (pdf)

at all running speeds, and better control of other
exhaust emissions.
Not only do RT-flex engines have a lower partload
fuel consumption than RTA engines but they
can be adapted through Delta Tuning so that their
part-load fuel consumtion is even lower. [1]
Owing to the interaction between fuel economy
and NO X
emissions, there is always the possibility
that fuel saving measures will have an impact on
NO X
emissions. As with all new marine engines
nowadays, Wärtsilä RTA and RT-flex engines are all
fully compliant with the NO X
emission regulation of
Annexe VI of the MARPOL 1973/78 convention.
Moreover, the engines in the Wärtsilä portfolio will
be adapted to meet the coming IMO NO X
reduction
level Tier II.
also possibly a higher propeller efficiency.
It must also not be forgotten that any fuel savings
achieved at the ship design stage will have benefits in
also reducing exhaust emissions.
If you have a project for which you wish to
explore the fuel-saving possibilities through derating
as set out in this paper, then please contact your
nearest Wärtsilä office. Our experts will be delighted
to calculate various alternatives for your evaluation.
References
1. German Weisser, ‘Fuel saving with RT-flex’,
Wärtsilä Switzerland Ltd, July 2004.
Conclusion
The paper shows that there are techniques to achieve
worthwhile reductions in the fuel consumption
of Wärtsilä low-speed engines when designing
newbuildings. The key approach is to use the
flexibility offered by the full power/speed layout field
to select a better layout point with a lower BSFC and
Published June 2008 by:
Wärtsilä Switzerland Ltd
PO Box 414
CH-8401 Winterthur
Tel: +41 52 262 49 22
Fax: +41 52 262 07 18
www.wartsila.com
— 11 — © Wärtsilä Corporation, June 2008