The Method to Calculate the Length of the Catenary for Anchored Vessel

The length of the anchor chain released directly influence the holding power of anchor and holding power of anchor decides the safety of the ship in the state of anchoring. In order to calculate the length of the catenary for anchored vessel in static hydraulic condition, Parabola and catenary mathematical model has been used in this paper to the data processing. These two kinds of thoughts are both based on the infinitesimal dividing model. The parabola method is using the Taylor series expansion to calculate the results of former 3~5 terms respectively, while catenary one uses the differential solving method. Through the example analysis to compare the accuracy of results obtained by these two methods, the conclusion can be obtained that parabola method is closely related to Taylor expansion terms. For a certain range of the anchored catenary length, the more Taylor series expansion, the more accurate results we can get; the gap of the results calculated by these two methods can be neglected. The catenary method is more accurate than that of parabolic one when the length of the catenary beyond this range.