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It has been about 40 years since nuclear-powered merchant ships were seriously discussed in the naval architecture community. But recent developments in commercial shipping include bigger, faster, and more powerful ships, where nuclear propulsion may be an option worth considering. The development of advanced ship designs opens an opportunity for high-speed maritime transportation that could create new markets and recover a fraction of the high value goods currently shipped only by air. One of the vessels being considered is FastShip, a large monohull ship that would require 250 MW in 5 gas turbine-waterjet units. An estimate of the operation cost of FastShip reveals that its success relies heavily, among other things, on the fuel price, a single factor that comprises more than one third of the total operating costs. The alternative, a nuclear FastShip, would save, per trip, almost 5000 tons of exposure to fuel price fluctuation, and about half of this savings would further be available for additional cargo and revenues. Nuclear power results in a more stable operation due to the relatively constant low price of nuclear fuel. The nuclear power option is suitable for high-power demand and long-haul applications and a reactor pack could be available within the decade. A candidate design would be the helium-cooled reactor, which has been revisited by several nuclear reactor design teams worldwide. For the FastShip a suggested plant would consist of two modular helium reactors, each one with two 50 MW helium turbines and compressors geared to waterjet pumps, plus a single 50 MW gas turbine. This vessel becomes more expensive to build but saves in fuel, and still provides margin for cost, weight and size optimization. This paper discusses general characteristics of a FastShip with such a nuclear power plant and also highlights the benefits, drawbacks, pending issues and further opportunities for nuclear-powered high-speed cargo ships.

In the case of conventional (displacement) hulls, model testing is based on the assumption (with or without certain refinements) that the total resistance can be expressed as:RT=RF+RR(1)where Rt is measured in the towing tank, and the frictional resistance, Rf, can be accurately estimated by the application of a friction line and the use of the calm-water wetted surface. It is assumed that the dimensionless residuary resistance RR is the same for the model and the prototype vessel. Our article may be considered to be an extension of the classic article by Wilson, Wells, and Heber (1978) to the more complex case of the surface-effect ship, as follows. Specifically, we opine that:RT=RF+RW+RH+RS+RM+RSPRAY(2)Here, Rw is the wave resistance of the vessel (caused by a combination of the actions of the cushion pressure and the two sidehulls), RH is the transom (hydrostatic) drag, Rs is the seal drag, Rm is the momentum drag, and RspRay is the spray drag. Rt is the only one of these quantities that is measured during the model test. The other components require the use of a variety of estimates. In the article, we present specific examples of our approach as applied to a number of tests on surface-effect ship models that we have studied in recent years.

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