Research on Design Program and Relevant Issues for Upgrading the Propulsion System of a Trailing Suction Hopper Dredger
Type:
Presented during:
WODCON XIX: "Dredging makes the World a better place" - 2010, Beijing, China
Authors:
YU Long, CHEN Xinquan, JIN Hua, ZHANG Ji
Abstract: Chinese domestic dredging projects are booming so dredging equipments are in great demand. Dredging companies not only pay attention to building new ships, but also turn to optimizing existing ships so as to improve dredging efficiency. This paper introduces an upgrade project of a 4500m3 trailing suction dredger, owned by CHEC Dredging Co.Ltd, which has been serving for many years. A pair of new ducted Controllable Pitch Propellers (CPP) is designed and installed on the dredger to replace old ones while main engine, original shafts and pitch adjusting apparatus are kept. The JDC4-55 series, originated by Shanghai Jiao Tong University, with HR nozzle has been taken as a final decision. A design program for design analysis in accord with the regulations has been developed and received the Chinese software copyright. With the aid of the program, it is easier to calculate the performance of new CPP at different pitches by taking advantage of the open water test and model test data embedded in the program. The location of the nozzle has been investigated by a 3D model to avoid interference with the rudder and shaft bracket. The nozzle connecting structure is modelled and its strength is calculated and checked based on an FE model, built by MSC.Patran. After the upgrade was finished, the dredger has worked at the Yangtze Estuary for 5 months and the operation data show that the substitution increases the thrust force when dredging. The amount of production rises at every voyage with equivalent fuel consumption. The new ducted CPP succeeds in saving energy and improving working efficiency.
Keywords: ducted controllable pitch propeller(CPP), open water test, design analysis, strength calculate, saveing energy and improve efficiency