Introduction to the structure of outboard motor waterjet propeller

The water jet propeller is an important part of the outboard motor, and according to the outboard motor manufacturer, it is a propeller in which the jet part of the propulsion mechanism is immersed in water, and the reaction force generated by the jet water is used to drive the ship forward. The structures are as follows:
Water jet propulsion is a traditional ship propulsion method. When people understood the function of the water pump, they began to transplant it to the ship for propulsion. The working principle of water jet propulsion is not very complicated. If the water pump is placed on the ship and sprays water to the stern when the water pump is working, a simple ship propulsion process can be realized. To realize the pump of this propulsion mode, the water inlet and outlet mechanism and the control mechanism are equipped with a water jet propulsion device.
Generally speaking, a water jet propulsion system is mainly composed of a water inlet pipe, a pump with an ejector-shaped discharge port, and a set of steering and reversing devices (see Figure 1). The rudder nozzle changes the direction of spraying water to the left or right, so that the steering function can be realized. The reversing thrust is generated by the reversing baffle reflecting the jet water forward, so as to achieve the purpose of reversing.
The inlet pipes are incorporated into the hull structure and are usually manufactured by the shipyard, with drawings provided by the water jet propulsion system manufacturer. The water inlet pipe is designed in the shape of a flow surface. The junction of the tube and the hull is streamlined to avoid turbulence in the water jet pump. The water inlet pipe is connected to the stern sealing plate by means of a flange, and it passes through the interior of the ship to the stern sealing plate from the bottom of the ship to form a water flow channel. A grill is installed at the inlet of the water inlet pipe to prevent large pieces of floating objects from entering the pipe. In case the pump is blocked, debris can be removed through the inspection hole at the top of the inlet pipe. The front part of the pipe passes through the water inlet pipe wall and enters the ship, and a sealing device is arranged at the front part of the pipe to prevent water from entering the ship.