The present disclosure discloses a method of ship ice resistance model experiment based on non-refrigerated model ice, including the following steps: determining the overall length L.sub.1, breadth B and scale ratio λ of a selected ship model; determining the size A.sub.1 of an experimental area for placing broken ice in the ship ice resistance model experiment; determining the characteristic length of model ice; determining the quantitative proportion of the model ice for each size under the target coverage ratio c of the model; obtaining the number of the model ice for each size under the target coverage ratio according to the quantitative proportion of the model ice for each size under the target coverage ratio c and the total area A.sub.2 of the model ice; determining the geometrical shape and parameters of each size under the target coverage ratio c of the model ice. The present disclosure solves the problems of poor economy and poor operability in a freezing model ice experiment of an ice basin, and provides a design method for carrying out a ship ice resistance model experiment in a towing tank.

Icebreaker (10) for a vessel (12), where the icebreaker (10) is connected to a bow (12a) of a vessel (12) for breaking up solid ice (40) floating on a water surface, the icebreaker (10) comprises a central part (14) sliding on a first side of the ice (40) and two or more side parts (16) sliding on an opposite part of the ice (40). The centre part (14) and the side parts (16) extend in parallel forward and works against each other when breaking the ice (40) to prevent the ice (40) from lifting, wherein a lower edge of the side parts (16), being in contact with the ice (40), is narrow and sharp to initiate breaking lines (50) in the ice (40), and the centre part (14) comprises a forward protruding cam structure (14a) to break the ice (40) between the side parts (16).

Provided is a control system for operating a floating wind turbine under sea ice conditions. The control system includes a detection device configured for detecting a formation of ice in a critical zone around the floating wind turbine, and an ice inhibiting device configured for manipulating the floating wind turbine in such a manner that the critical zone is free of a threshold amount of the detected formation of ice. Furthermore, a floating wind turbine is provided which includes a wind rotor including a wind rotor including a blade, a tower, a floating foundation, and an above-described control system. Additionally, a method for operating a floating wind turbine under sea ice conditions is provided.

The invention relates to the field of shipbuilding and more specifically to the screw propeller for a pod drive of a vessel, particularly an ice-going vessel, providing movement both ahead and astern in icy conditions where the ice is traversable, while also providing steering for the vessel, and to a pod drive comprising said screw propeller. To reduce the weight, and consequently the cost, of the pod drive, the screw propeller comprises a propeller hub, made so that it can be rigidly attached to the conical tailpiece of the propeller shaft, and screw propeller blades, each comprising a blade foil and a blade flange made in one piece, mounted on the propeller hub. The blade foil passes into the blade flange via a fillet joint forming the weakest portion for the possible destruction of the blade in the cross section of its foil, located immediately adjacent to the fillet joint. The outer surface of the blade flange has a profile, in its meridional cross section, curved inwards towards to the propeller axis, to reduce the distance from said blade foil cross section to the propeller axis.

The present disclosure discloses a method of ship ice resistance model experiment based on non-refrigerated model ice, including the following steps: determining the overall length L.sub.1, breadth B and scale ratio λ of a selected ship model; determining the size A.sub.1 of an experimental area for placing broken ice in the ship ice resistance model experiment; determining the characteristic length of model ice; determining the quantitative proportion of the model ice for each size under the target coverage ratio c of the model; obtaining the number of the model ice for each size under the target coverage ratio according to the quantitative proportion of the model ice for each size under the target coverage ratio c and the total area A.sub.2 of the model ice; determining the geometrical shape and parameters of each size under the target coverage ratio c of the model ice. The present disclosure solves the problems of poor economy and poor operability in a freezing model ice experiment of an ice basin, and provides a design method for carrying out a ship ice resistance model experiment in a towing tank.

Icebreaker (10) for a vessel (12), where the icebreaker (10) is connected to a bow (12a) of a vessel (12) for breaking up solid ice (40) floating on a water surface, the icebreaker (10) comprises a central part (14) sliding on a first side of the ice (40) and two or more side parts (16) sliding on an opposite part of the ice (40). The centre part (14) and the side parts (16) extend in parallel forward and works against each other when breaking the ice (40) to prevent the ice (40) from lifting, wherein a lower edge of the side parts (16), being in contact with the ice (40), is narrow and sharp to initiate breaking lines (50) in the ice (40), and the centre part (14) comprises a forward protruding cam structure (14a) to break the ice (40) between the side parts (16).

The invention relates to the field of shipbuilding and more specifically to the screw propeller for a pod drive of a vessel, particularly an ice-going vessel, providing movement both ahead and astern in icy conditions where the ice is traversable, while also providing steering for the vessel, and to a pod drive comprising said screw propeller. To reduce the weight, and consequently the cost, of the pod drive, the screw propeller comprises a propeller hub, made so that it can be rigidly attached to the conical tailpiece of the propeller shaft, and screw propeller blades, each comprising a blade foil and a blade flange made in one piece, mounted on the propeller hub. The blade foil passes into the blade flange via a fillet joint forming the weakest portion for the possible destruction of the blade in the cross section of its foil, located immediately adjacent to the fillet joint. The outer surface of the blade flange has a profile, in its meridional cross section, curved inwards towards to the propeller axis, to reduce the distance from said blade foil cross section to the propeller axis.

A laser-powered ice-penetrating communications payload delivery vehicle for sub-ice submarine missions enables under-ice operations to exchange information with terrestrial facilities or satellite networks with communications methods otherwise blocked by an ice cap. The vehicle comprises an electronics bay, a payload bay, optics bay, and a melt optic with laser. The system and method of establishing communication where the vehicle, tethered to a sub-ice vessel, is released. The vehicle ascends to the bottom of an ice sheet and uses a laser to melt the ice, forming a borehole through which the vehicle continues to ascend. When buoyancy no longer advances the vehicle beyond sea level, the vehicle continues to melt a conical opening through the ice until unobstructed atmosphere is reached and bi-directional communication is established. Where the melting capacity cannot reach ice to continue melting, the vehicle mechanically advances itself toward the surface to establish high bandwidth, bi-directional communication.

A floating drilling platform for offshore oil/gas drilling and exploration in ice-infested polar areas comprises a deck module, a hard compartment, and a soft compartment sequentially connected from top to bottom. The bottom of the deck module is connected to the top of the hard compartment by evenly distributed column. Both the hard and the soft compartments are cylinders centrally arranged with center wells. The deck module is also centrally arranged with a center well. The hard compartment, the soft compartment and the deck module are coincident with a centerline. The outer diameter of the soft compartment, as well as that of the deck module, is larger than that of the hard compartment. The top of the hard compartment is designed with a circular inclined plane upwardly and outwardly arranged at the outer edge. The top of the circular inclined plane is connected to the bottom of the deck module.

A laser-powered ice-penetrating communications payload delivery vehicle for sub-ice submarine missions enables under-ice operations to exchange information with terrestrial facilities or satellite networks with communications methods otherwise blocked by an ice cap. The vehicle comprises an electronics bay, a payload bay, optics bay, and a melt optic with laser. The system and method of establishing communication where the vehicle, tethered to a sub-ice vessel, is released. The vehicle ascends to the bottom of an ice sheet and uses a laser to melt the ice, forming a borehole through which the vehicle continues to ascend. When buoyancy no longer advances the vehicle beyond sea level, the vehicle continues to melt a conical opening through the ice until unobstructed atmosphere is reached and bi-directional communication is established. Where the melting capacity cannot reach ice to continue melting, the vehicle mechanically advances itself toward the surface to establish high bandwidth, bi-directional communication.