ADDED RESISTANCE IN WAVES OF INTACT AND DAMAGED SHIP IN THE ADRIATIC SEA

In this paper the ship added resistance in regular head waves and at different sea states in a certain frequency range at different forward speeds was calculated.Calculations were conducted using hydrodynamic software.Since after a maritime accident a damaged ship often has to be removed from the place where the accident occurred, the seakeeping characteristics of the damaged ship were also calculated.The response of the damaged ship was simulated using two models: damage simulated as an increase in the ship displacement mass and as a flooded tank within the midship area.Calculations are based on the linear potential flow theory and added resistance was determined by the wave drift force as the second order wave load.The quadratic transfer function QTF which describes low-frequency second order wave loads was approximated by its zeroth term only, i.e. by the drift load at incoming wave frequencies.The mean added resistance values of the intact and the damaged ship were compared.The calculation results show that added resistance in waves of the damaged ship with a flooded tank differs slightly from the added resistance in waves of the damaged ship with an increased displacement.