Man B&W S50ME-B9.3-TII, Руководство по проекту

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MAN B&W 2.11
Page 1 of 1
MAN Diesel
MAN B&W MC/MC-C/ME/ME-C/ME-B/-GI engines 198 38 43-4.5
Once the specified MCR (M) of the engine has
been chosen, the specific fuel oil consumption at
an arbitrary point S
1
, S
2
or S
3
can be estimated
based on the SFOC at point ‘1’ and ‘2’.
These SFOC values can be calculated by using
the graphs for the relevant engine type for the
propeller curve I and for the constant speed curve
II, giving the SFOC at points 1 and 2, respectively.
Next the SFOC for point S
1
can be calculated as
an interpolation between the SFOC in points ‘1’
and ‘2’, and for point S
3
as an extrapolation.
The SFOC curve through points S
2
, on the left
of point 1, is symmetrical about point 1, i.e. at
speeds lower than that of point 1, the SFOC will
also increase.
The abovementioned method provides only an
approximate value. A more precise indication of
the expected SFOC at any load can be calculated
by using our computer program. This is a service
which is available to our customers on request.
Power, % of M
110%
100%
90%
80%
70%
80% 90% 100% 110%
Speed, % of M
M
5
7
2
1
S
2
S
1
S
3
4 3
I II
Fig. 2.11.01: SFOC at an arbitrary load
198 95 962.2
Fuel Consumption at an Arbitrary Load