WÄRTSILÄ WARTSILA 50DF, Product Manual

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Table 13-1 ISO 8178 test cycles
100 100 100 100 100 Speed (%) D2: Constant-speed
auxiliary engine applica-
tion
10 25 50 75 100 Power (%)
0.1 0.3 0.3 0.25 0.05 Weighting
factor
100 100 100 100 Speed (%) E2: Constant-speed
main propulsion applica-
tion including diesel-
electric drive and all
controllable-pitch pro-
peller installations
25 50 75 100 Power (%)
0.15 0.15 0.5 0.2 Weighting
factor
Idle Intermediate Rated Speed C1: Variable -speed and
-load auxiliary engine
application
0 50 75 100 10 50 75 100 Torque
(%)
0.15 0.1 0.1 0.1 0.1 0.15 0.15 0.15 Weighting
factor
Engine family/group
As engine manufacturers have a variety of engines ranging in size and application, the NO
x
Technical Code allows the organising of engines into families or groups. By definition, an
engine family is a manufacturer’s grouping, which through their design, are expected to have
similar exhaust emissions characteristics i.e., their basic design parameters are common.
When testing an engine family, the engine which is expected to develop the worst emissions
is selected for testing. The engine family is represented by the parent engine, and the
certification emission testing is only necessary for the parent engine. Further engines can be
certified by checking document, component, setting etc., which have to show correspondence
with those of the parent engine.
Technical file
According to the IMO regulations, a Technical File shall be made for each engine. The Technical
File contains information about the components affecting NO
x
emissions, and each critical
component is marked with a special IMO number. The allowable setting values and parameters
for running the engine are also specified in the Technical File. The EIAPP certificate is part of
the IAPP (International Air Pollution Prevention) Certificate for the whole ship.
IMO NOx emission standards
The first IMO Tier 1 NOx emission standard entered into force in 2005 and applies to marine
diesel engines installed in ships constructed on or after 1.1.2000 and prior to 1.1.2011.
The Marpol Annex VI and the NO
x
Technical Code were later undertaken a review with the
intention to further reduce emissions from ships and a final adoption for IMO Tier 2 and Tier
3 standards were taken in October 2008.
The IMO Tier 2 NOx standard entered into force 1.1.2011 and replaced the IMO Tier 1 NOx
emission standard globally. The Tier 2 NOx standard applies for marine diesel engines installed
in ships constructed on or after 1.1.2011.
13-2 Wärtsilä 50DF Product Guide - a16 - 9 September 2016
Wärtsilä 50DF Product Guide 13. Exhaust Emissions