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4.5 Comparison of Powering Performance
Figure 14 & 15 show the comparison of CR curves and Admiralty coefficients (Cadm) for the trimaran
and the similar mono-hull ships, respectively. The propulsion efficiency of trimaran is almost same as
the others. The trimaran shows good powering performance in most speed range though the wetted
surface area is increased by 28% comparing to the others.

05

Figure 14: Comparison of CR curves Figure 15: Comparison of Adimiralty coefficients

5 CONCLUDING REMARKS
The 2,500ton class trimaran was designed and the powering performance was investigated. The
results obtained from the research can be summarized as follows.
- The longitudinal location of side-hull has a large influence on the wave resistance of the
trimaran while the side-hull form and transverse location has a small influence on it.
- The symmetry side-hull shows comparatively good performance on wave resistance among
three kinds of side-hull forms.
- The optimum location of side-hull is changed according to the ship's speed. Then the optimum
location moves to the stem or stern part as the trimaran runs fast.
- The trimaran shows favorable resistance performance when the side-hull stem is located near
the primary wave hollow generated by the main hull.
- The trimaran is superior to the similar mono-hull ships in powering performance except the
low speed range though the wetted surface area is increased by 28% comparing to the latter.
- The optimization of principal dimensions and the hydrodynamic performance including
seakeeping and maneuvering characteristics for the trimaran should be studied synthetically.
References

Benjamin B. Ackers et al. (1997). An Investigation on the Resistance Characteristics of Powered
Trimaran Side-Hull Configurations. SNAME Transactions 105,349-373.
http:llwww. trimaran.dera.gov.uW
Kang, K. J., et al. (2000). Development of the Core Technologies of Hydrodynamic Performance for
Large High Speed Special Ship (4/4). KRISO report UCEOO918-2296
Kim, D. H., et al. (1999). Estimation of the Optimum Position for the Side Hulls of a Trimaran by
Panel Method. 4th J-K Joint Workshop on Ship & Marine Hydrodynamics, Fukuoka, Japan
RNA (2000). RV 'TRIT0N':Trimaran Demonstrator Project. InternationaZ conference proceeding