Study On The Key Technologies In General Design Of Emergency Rescue And Salvage Tug

A study on the key technologies involved in the general design of a 8000kW muti-purpose tug is presented in this thesis, as well as optimizes propulsion system layout and hull form of the tug. It provides a support for further improving the general design technology of the multi-purpose tug development.The mainly research work and conclusions of this thesis are as follows:(1) In terms of functional requirement, working capacity, equipment, system configuration and economic aspect, a comparison of the different applications of propulsion type in multi-purpose tug is conducted.As well as an optimal propulsion system solution for multi-purpose tug is determined. The results indicate that:compared with conventional propeller solution, a compact Azipod propulsion solution has higher overall cost-effectiveness. Meantime, as Azipod propulsion system equipment is becoming sophisticated, numerous advantages such as high efficiency, energy-saving and environment-friendliness are shown in terms of operation and management of multi-purpose tug.(2) The emergency rescue tug should have a high speed as well as a large pull force when at low speed, thus normal hull form has no bovious resistance reduction.Through hull form optimization,an effectively reduces energy loss created by the wave-making of hull is botained, making it particularly suitable for multi-purpose tug.(3) Multi-purpose tug needs to be designed in such manner to sufficiently guarantee the long time safty working in rough sea state with good motion performance. Based on a comnined method of numerical analysis and model test, the hydraulic performance characteristics of multi-purpose tug are determined. As a result, the dynamic response of vessels under iregular wave conditions are obtained, thus providing a basis and reference for analysis of the actual working condition of multi-purpose tug, and providing a realistic guide for engineering practices.