A suite of midlife alterations, some to the hull, are being considered for MV WARSASH to reduce the ship's future environmental impact and running costs. A model has been built of MV WARSASH incorporating a stern flap and bulbous bow. the model has a 1:20 scale. The model is to be used to determine the total resistance of MV WARSASH at a speed of 9.2kts and a displacement of 7350t. The hope is that the hull modifications will dramatically reduce the ship's resistance, and that this would make Engine Power Limitation (EPL) a practical way of reducing CO2 emissions and fuel costs. At a displacement of 7350t MV WARSASH has a wetted surface area of 2040m2 (including the surface area of the proposed stern flap and bulbous bow).

Determine the following. a) The required model speed, mass in fresh water and wetted surface area. b) The frictional resistance of the model and ship using the ITTC method. c) The viscous resistance of the model and ship using the following formula for form factor. (1 + k) = 2.76(L/V1/3)-0.4 'Couser et al. .. an empirical form factor formula for monohulls' d) The model and ship residual resistance given a measured model total resistance of 42.ON. e) The ship's total resistance. The ship correlation factor is 1.15 (SCF), the hull efficiency is 101% (nH), the propeller efficiency 65% (np), the transmission efficiency is 97% (nT), and the mechanical efficiency is 82% (nm). f) The required naked effective power (PEN), effective power (PE), thrust power (PT), delivered power (PD), shaft (brake) power (Ps) and indicated (installed) power (PI). Further model tests have been commissioned to build a curve of ship resistance to enable the effectiveness of hull form changes to be evaluated over a broad speed spectrum. The following table details recorded total model resistance at a range of Froude numbers. FN 0.15 0.20 0.25 0.30 0.35 0.40 RTM (N) 42.0 84.0 87.4 173.0 179.8 222.6 g) Curves of viscous, residual, and total resistance for the ship at a displacement of 7350t