Azimuthing, podded propulsors belong these days to intensely developed rotating machines in shipbuilding industries tracing the way to an all electric concept. They make use of powerful electric motors located in flow suited housings, having one or two propellers suspended on one or two shaft ends as pulling/pushing units. Their respective location at the ship afterbody allows to use them as both propulsive units and steering devices throughout use of vectoring thrust forces. Moreover, they are controlled by state of the art automation systems, flexibly to operational conditions. This specificity gives many advantages like increased propulsive efficiency and very high operability together with high levels of ship safety and positive impacts towards the natural environment. Necessity of modern electric power plants application and lack of internal shaftlines have resulted in innovative approaches to designs of podded ships. All present benefits and new prospects of use high-tech superconductive electric motors and fuel cells based power plants have stimulated European Union to initiate complex research works in order not only to recognize phenomena accompanying podded propulsors but to lay out effective directions of their development as well. That is why CTO could participate in two European projects of the 5th Framework Programme - Optipod and Fastpod, dealing with versatile investigations of podded ships. Especially the second project was directed to very high propulsive powers what resulted in building multipropulsor systems showing out further benefits of this kind of propulsion. This paper presents selected results of wide investigations of the very fast, Panama size Cargo Vessel, distinguishing innovative approaches towards model tests. Thus four pure pods combinations, being the basic concept for Panamax options, were tested as two alternatives: as all pulling pods or as two couples of pods working in the contra-rotating (CRP) mode being installed on the ship hull with a central skeg. From other hand, electric motor based hybrid alternatives were making use from widely known classical concepts like tandem propellers situated behind a central stern bulb and twin skeg hull solution with classical propellers, supported by two pod units interacting also in the contrarotating mode. In each case, the most aft located couple of pods units was used as advanced steering and stopping devices. A risk of cavitation on podded propellers, resulting from their slewing movements, has stimulated CTO researchers to design and investigate dedicated flaps so as to restrain movements of pods and use only flaps for steering at high service speeds. The incoming news from the USA about tested there, small sized superconducting electric motors, are so encouraging that an adequate couple of pods, with seriously reduced dimensions, is a subject of respective investigations at CTO.
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