Resistance Estimation

The bare hull resistance is determined at model scale using one of fifteen available empirical methods given below:

• Holtrop and Mennen

• Guldhammer and Harvald

• Dankwardt

• Van Oortmerssen

• BSRA Methodical Series

• Series 60

• Takashiro

• Taylor-Gertler

• Radojcic (Series 62 type hullforms)

• Radojcic (Series 65 type hullforms)

• Savitsky

• Round Bilge (Monohulls)

• Round Bilge (Catamaran)

• ZIPS (Hard Chine Catamaran)

• Pham (Hard Chine Catamaran)

The ship scale bare hull resistance is then derived from the above using the 1978 ITTC Performance Prediction Method. To achieve this, Hydro will determine a suitable form factor for the design, with you then able to alter this value if desired. Similarly the ship-model correlation allowance may be determined by Hydro or equally it can be left to your discretion.

The effective power is then calculated after the inclusion of an appendage resistance, calculated according to the Holtrop and Mennen method.