1,264,153. Reducing resistance to propulsion. H. T. LUNDELL. 19 Feb., 1969 [19 Feb., 1968], No. 9115/69. Heading B7M. In a vessel having a non-bulbous bow and a block-coefficient of less than about 0À85 the resistance to motion of the vessel is reduced by positively driving, a flow or stream of water forward from the bow of the vessel below the water-line to set up ahead of the vessel a wave system which is out-of-phase with the bow wave system set up by the motion of the vessel. The interaction of the two systems results in a reduction in the wave-making resistance of the vessel to motion. In the embodiment shown the forepart 30 of a vessel has a vertical centrally located flow tunnel or duct 32 having an outlet below the inlet, the duct forming a reversing path for water flowing in at the top. Impeller 34 in the duct drives the outflowing water forward to produce the requisite out-of-phase wave system. In another embodiment a high velocity, swingable jet of water is directed forward.
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