Man V8-1200 - Page 57

Propeller system
55
Power consumption of propeller too great
The power consumption of the propeller is greater
than the maximum power of the engine. The
engine can therefore not reach its nominal speed
(operating point Ã).
À Engine power curve
Á Propulsion resistance curve
 Speed/power reduction curve
à Operating point for a propeller that is too big
Power consumption of propeller too small
The propeller cannot absorb and transmit the
power available from the engine. The engine
speed is significantly higher than the rated speed
(operating point Ã).
À Engine power curve
Á Propulsion resistance curve
 Speed/power reduction curve
à Operating point for a propeller that is too small
0
10
20
30
40
50
60
70
80
90
100
40 50 60 70 80 90 100 110 120
Rpmin%
Powerin%
1
2
3
4
0
10
20
30
40
50
60
70
80
90
100
40 50 60 70 80 90 100 110 120
Speedin%
Powerin%
1
2
3
4