Development of ice resistance estimation system using empirical formula

In the beginning stage of icebreaking vessel design, the estimation of ice resistance with high reliability using empirical formula is very important to decide power of ship. This paper deals with the prediction methods considering hull form under the loaded waterline. Main idea comes from several empirical formulas as like B. P. Ionov, Enkvist and Shimansky methods. These empirical formulas show very useful results when designing vessels with icebreaking bow shape, because the ice resistance of designed hull forms can be estimated in advance. Authors developed the methods to calculate respective components of ice resistance. Modified prediction methodology for icebreaking and buoyancy components is suggested so that the hull shape under loaded waterline can be directly reflected in the calculation of ice resistance. Especially calculated clearing plane was replaced with DLWL (design load water line) plane in Ionov method. GUI (graphical user interface) skills were applied in the system to easy control the input and output data of hull form. Some results are compared between results of model test and calculation results. Accuracy of estimation program will be discussed in this paper.