Large engineering ship propeller - installation gap between ship propeller and hull

Large engineering ship propeller - installation gap between ship propeller and hull

Large engineering ship propeller - increase the installation gap between the propeller and the hull.

Large engineering ship propellers - the clearance should be above 0.12D to 0.2D, with larger propeller diameters and larger clearances to reduce surface excitation forces transmitted to the hull, taking into account the actual situation of the ship.

Large engineering ship propellers - When the clearance cannot be increased, a vibration reduction hole can be set up on the hull, which is a concave "hole" above the corresponding hull of the propeller. The size of the "hole" and the concave size correspond to the size of the propeller diameter, which is equivalent to using the spring effect of water quality points to reduce the surface excitation force transmitted to the hull.

Large container propellers - equipped with damping materials.

Large container propellers - steel or rubber damping materials are laid in a sufficiently large area above the propellers inside the ship's hull. When laying, attention must be paid to the cleanliness of the steel structure surface to ensure the bonding effect between the damping materials and the steel structure. The damping materials are used to generate tensile, bending, shear and other deformations inside, absorb a large amount of incident energy, and convert vibration energy into thermal energy for consumption.

Large container propeller - increase the number of blades.

Large container propellers - Generally speaking, increasing the number of blades can improve the balance of the propeller, thereby reducing the surface force generated by the propeller on the main hull.

Large container propeller - improving the line shape of the rear of the ship.

30M patrol boat propeller - can improve the wake distribution at the stern and enhance the uniformity of the wake field. 30M patrol boat propeller - of course, considering the complexity of the wake field, it needs to be combined with ship model tests to better achieve this. Qualitatively speaking, adopting a dual tail shape and adding a tail fin can effectively improve tail wake.

30M patrol boat propeller - to avoid generating air bubbles.

The fundamental cause of the NCP series adjustable propeller cavitation phenomenon is the rapid water flow velocity on the blade section, significant pressure drop, and excessive pressure per unit area of the propeller. Cavitation not only causes erosion of the propeller, but also induces excitation of the propeller. NCP series adjustable propeller - improves the cavitation phenomenon of the propeller, which can be alleviated by increasing the blade surface ratio and reducing the propeller speed.

NCP series adjustable propeller - equipped with a guide pipe.

NCP series adjustable propeller - For propellers with high loads, ducted propellers can be used. The NCP series adjustable propeller - guide tube can improve the efficiency of the propeller on the one hand, and on the other hand, it can improve the distribution of the wake, while bearing a considerable part of the load originally acting on the propeller, thereby avoiding the generation of air bubbles and vibration in the propeller.