Is the water jet propeller good or propeller propeller good?
However, the ship tends to be large, and the stern vibration, structural damage, noise and erosion caused by propeller vibration are problems when the main engine is used. The fundamental reason lies in the spiral blade propeller exciting load, on the ship after work in the wake of the uneven prone unstable cavitation locally, which leads to the pressure acting on the hull propeller, amplitude and phase are constantly changing.
Water jet propulsion has the advantages of excellent maneuverability and flexibility, high speed and high efficiency, promote the host is not easy to overload, suitable for shallow water navigation, generally used in high speed and high performance ships, and gradually applied to large and medium-sized ships.Propeller blade: by hub and a plurality of radial fixed to the hub on the composition of the propeller, commonly known as propellers. The propeller is installed below the stern line and rotated by the main engine (see the ship's power unit) to push the water toward the ship and push the boat forward with the counterforce of the water. The propeller is simple in structure, light in weight and efficient, and is protected below the waterline. The propeller is the main propulsion tool of modern ships. Nowadays most ships are propelled by propellers.
The water jet propeller of a speedboat has the advantages of propeller and propeller.Jet propulsion: a propeller that produces thrust by the action of a jet of water. Water jet propulsion consists of water pumps, water pipes, water pipes, powered by water pump, water will be sucked from the bottom hole, by the side of the pipe, the water is discharged from the ship after the direction, by the reaction of water propulsion ship. The mechanical part is mounted in the ship and is well protected. The nozzle is variable in direction and convenient for ship handling. But the nozzle is limited in diameter, the efficiency of the pipeline and pump is not high, so the efficiency of the whole system is low, and because the water in the water pump and nozzle increases the weight of the ship, so it is seldom used in the general speedboat.
