ISSN (Print): 1844-6116 ISSN (Online): 1884-6116
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Journal of Marine technology and Environment Year 2019, Vol.2 5.2 The effect of the wind velocity variation on the output
power at a ship speed of 20 nd and the other parameters are maintained constant Parameters C rot =5, CL = 12,5 and C D = 0,2
changed due to the change in the value of the rotation coefficient C rot . The variation in the net output power is calculated for a rotation coefficient C rot of 2, 3, 4, 5, 6. We can see
remain constant. It can be seen here that the variance model is the same as in the previous case, but the magnitude of the net power is higher when the ship speed increases from 15 knots to 20 knots.
that the higher the coefficient of rotation, the net output power decreases. The calculations were made for CL = 12,5, C D = 0,2, Vt = 5 m/s and
Vs = 15 Nd.
Table 1.4: Output power values for three suitable winds from different directions: Output net power (kW) Degre es (ď § ) 70 180 260 Figure 5 Net output power (kW) generated by the Flettner Rotor at various wind speeds, the ship's speed remaining constant at 20 Nd
C rot
C rot
C rot
C rot
C rot
=2
=3
=4
=5
=6
40,36 -4,73 54,18
39,48 -8,58 52,31
37,82 -15,76 48,81
35,18 -27,22 43,23
31,34 -43,87 35,12
5.4 Effect of rotation coefficient C rot on the power consumed Pcon
5.3 Effect of rotation coefficient C rot on the net output
The power consumed is calculated for values of the rotation coefficient C rot of 2, 3, 4, 5, 6. Power
power Pnet
consumption increases with the increase of the rotation coefficient C rot . The calculations were performed for constant values of
CL = 12,5, C D = 0,2,
Vt = 5
m and Vs = 15 Nd. s
Figure 6 The effect of the rotation coefficient C rot on the net output power Pnet at a ship speed of 15 Nd The rotation coefficient is the ratio of the rotational speed of the rotor to the apparent wind speed. In the figure above we can see how the net power output has
Figure 7 Effect of rotation coefficient on power consumption (kW) at a ship speed of 15 Nd
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