Straight wall constant wetted length slideway type round bilge speed boat shape

Abstract

The invention discloses a straight wall constant wetted length slideway type round bilge speed boat shape which is characterized in that a boat body comprises two straight wall constant wetted length round bilge lateral bodies in left-right symmetry, slideway tops and slideways, the straight wall constant wetted length round bilge lateral bodies are formed by straight wall contour lines, slideway contour lines, stern cross section lines, stern bottom oblique ascensions, midship cross section lines and midship bottom oblique ascensions. The straight wall constant wetted length slideway type round bilge speed boat shape has the advantages that the wetted length is constant, during sailing, waves and flying foams on the outer side of the boat body are reduced greatly, the waves, flying foams and air flows on the inner side of the boat body flow through the slideways and flow out towards the rear of the boat at high speed, parts of the energy of the waves and flying foams on the inner side of the boat body are recycled by the slideways (equals to wave and foam elimination) and converted into the dynamic lifting force of the boat body along with the air flows, the operability, navigability and seakeeping performance of the boat shape are increased greatly, and the boat shape is applicable to sea conditions 1-2 levels higher than those which traditional speed boats are applicable to. In addition, due to the fact that the wetted length of the boat shape is constant, the performance of the boat shape can be favorably and theoretically analyzed and researched by using length Froude number.

Description

technical field [0001] The invention relates to a speedboat type, in particular to a military and civilian double-hull speedboat suitable for a Froude number greater than 0.5 to 1.3 in length and capable of normal navigation under relatively high sea conditions, and belongs to the technical field of ship type. Background technique [0002] The round bilge speedboat has greater wave-making resistance and smaller droplet resistance when navigating in the transition state, and the sum of these two resistances accounts for more than 50% of the total resistance. The proportion of foam resistance increases, and the proportion of the sum of these two resistances to the total resistance continues to increase, even exceeding 70% of the total resistance. Waves and droplets are inherent physical phenomena when speedboats sail, and they are unavoidable. The current catamaran speedboat hardly improves the resistance, but only keeps the hull in a relatively stable sailing state supported ...

AI Technical Summary

Problems solved by technology

[0003] When the traditional catamaran round bilge speedboat sails in low-speed displacement state, due to the small length-to-width ratio of the speedboat, it has greater wave-making resistance compared with the catamaran displacement ship. The soaked length will be significantly reduced. At this time, there is an obvious wave-making resistance peak, and the wave-making resistance is relatively large; The motion stability performance is greatly reduced, the seakeeping performance is deteriorated, and even in slightly higher sea conditions, it cannot sail normally, thus limiting the range of operating conditions of traditional catamaran round bilge speedboats

Different from conventional displacement ships, as a dynamic lift ship, the speedboat will change its navigation state with the change of speed when sailing, mainly the wetted length of the hull, hull draft and hull pitch angle. , which makes it inconvenient to use the length Froude number to analyze its performance

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