Table 2. Principal dimension of the simulated ship

Fig.5 Characteristics of propeller force

Fig.6 Robinson's curve of the simulated ship.

　

3.3 Simulated results

Using above mathematical model, typical simulated results are shown. In each simulation, the main engine is governed a constant revolution (=450rpm).

　

(1) Acceleration and Deceleration of ship

Fig.7 shows the simulated accelerating motion from DEAD SLOW to HALF and deceleration from HALF to STOP. The simulated propeller revolution fairly responds to the ordered one, even in the decelerating zone.

　

Fig.7 Results of acceleration (DS→S→H→STOP)

Fig.8 Results of acceleration (F→astern H)

　

(2) Stopping and Astern of ship

Fig.8 shows the simulated typical stopping maneuver from HARBOR FULL to ASTERN HALF. The propeller revolution well gets astern soon and ship can stop easily.

　

4. CONCLUSION

　

The following conclusions are obtained from this research.

1) FPP's revolution can be easily changed in the slipping zone by using this system, although the main engine is governed constant revolution.

2) Astern and ahead maneuvering can be also performed by this system.

3) The mathematical model for this simulation including engine, clutch, propeller and ship is useful for the design and evaluation of the whole propulsion system.

References

[1] Tamori Y. et al., "Electronically Controlled Clutch", Jou. of the M.E.S.J., Vol.32, No.4 (1997), p297 (Japanese)

[2] Dundone M. W., "Power Division by the Omega Drive System", S.AE, N0.730737(1973), p.1

[3] Van Lammeren, W.P.A, et. al The Wageningen B-Screw Series" Trans of S.N.A.M.E vol.77 (1969), p.269

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