Czesław Dymarski

Computational model for simulation of lifeboat motions during its launching from ship in rough seas

ABSTRACT This paper presents a computational model which describes motion of an object of six degrees of freedom (DoF), intended for simulation of spatial motion of one- or two- rope-sling lifeboat or rescue boat during its launching from ship in rough sea. This is a complex model which accounts for sea conditions as well as elasticity and damping properties of davit’s elements and mechanisms, rope and boat hull. Also, are presented results of example calculations for an assumed set of technical parameters of davit and boat as well as sea conditions.

An integrated hydraulic drive system of a novel device for launching lifeboats from large passenger ships

An integrated hydraulic drive system of a novel device for launching lifeboats from large passenger ships This paper presents a continuation of the projects [5, 6] dealing with the novel concepts of evacuating people from large passenger ships. A novel integrated drive and control system for chain lift with lifeboats fastened on it as well as for stern port- ramp, is presented. Additional novel elements is the application of the stern port - ramp fitted with a buoyancy element, and its increased capability of automatic adjusting its operational deflection in the case of a large forward trim of ship. It increases safety and comfort of evacuation in the difficult conditions, but to obtain it a more complex drive and control system has been required to be designed.

A concept of drive and control system of a novel device for people evacuating from large passenger ships

A concept of drive and control system of a novel device for people evacuating from large passenger ships Year-after-year increasing number and size of sea-going passenger ships make it necessary to search for novel methods of evacuation of passengers from such large objects or to improve those which have been applied so far. This paper presents a concept of one of the original methods, in which, a.o., chain lifts have been applied to hold up life boats during voyage as well as to launch them in case of evacuation. Technical assumptions and requirements as well as schematic diagram of the hydraulic drive and control system of the lift, is presented.

Design of Structure of Tension Leg Platform for 6 MW Offshore Wind Turbine Based On Fem Analysis

Abstract The article presents the calculation and design stages of the TLP platform serving as a supporting construction of a 6 MW offshore wind turbine. This platform is designed to anchor at sea at a depth of 60 m. The authors presented the method of parameterization and optimization of the hull geometry. For the two selected geometry variants, the load and motion calculations of the platform subjected to wind, wave and current under 50-year storm conditions were performed. The maximum load on the structure was determined in these extreme storm conditions. For these loads, the MES calculation of the designed platform was performed for the selected variant. Authors have presented a method for calculating maximum wind, wave and current stresses on the structure during the worst storm in the past 50 years. For these loads the MES endurance calculations of the designed platform were made. Based on the results of these calculations, the required structural changes and recalculations have been made in succession to the structural design of the platform, which meets the design requirements and has the required ad hoc strength. The article contains stress analysis in „difficult“ nodes of constructions and discusses ways of solving their problems. The work is part of the WIND-TU-PLA project from the NCBR Research Agreement (Agreement No. MARTECII / 1/2014).

A Numerical Model to Simulate the Motion of a Lifesaving Module During its Launching from the Ship’S Stern Ramp

Abstract The article presents a numerical model of object motion in six degrees of freedom (DoF) which is intended to be used to simulate 3D motion of a lifesaving module during its launching from a ship using a stern ramp in rough sea. The model, of relatively high complexity, takes into account both the motion of the ship on water in changing sea conditions, and the relative motion of the ramp with respect to the ship. The motion of the ramp changes and strongly depends on its constructional and geometrical parameters. The presented model takes into account the displacement of the submerged part of the ramp, as well as its damping in the water and the interaction with the module moving on it. The results of test simulation of a module launching from the ship in still water are included.

Computational Simulation of Motion of a Rescue Module During its Launching from Ship at Rough Sea

Abstract This paper is a continuation of the work titled: “A computational model for simulation of motion of rescue module during its launching from stern ramp of a ship at rough sea”. It presents results of computer simulations of motion of a rescue module with embarked persons during its launching on rollers along stern ramp of a ship at rough sea. Te simulations were conducted for a selected ship fitted with a launching ramp, for a few selected scenarios of sea conditions. It was assumed that during this operation the ship drifts across direction of wave propagation.

Laboratory Test Rig for Examining Aggregate Mining from Seabed Using the Airlift Method

Abstract The use of the Airlift method for transporting the mined aggregate from the seabed to the deck of the mining ship is an alternative for presently used solutions, such as suction pumps or scoop transport for instance. Building the laboratory test rig was preceded by tests in natural conditions. The rig was designed in such a way as to model these conditions as close as possible, and to have potential for further development.

Technology Concept of TLP Platform Towing and Installation in Waters with Depth of 60 m

Abstract The article is part of the design and research work conducted at the Gdansk University of Technology, Faculty of Ocean Engineering and Ship Technology, in cooperation with a number of other research centres, which concerns offshore wind farms planned to be built in the Polish zone of the Baltic sea in the next years. One of most difficult tasks in this project is building suitable foundations for each power unit consisting of a tower and a wind turbine mounted on its top. Since the water regions selected for building those wind farms have different depths, there was need to study different possible technical variants of this task, with the reference to both the foundation structures themselves, and the technology of their transport and setting, or anchoring. The article presents the technology of towing, from the shipyard to the setting place, and installation of the foundation having the form of a floating platform of TLP (Tension Leg Platform) type, anchored by tight chains to suction piles in the waters with depth of 60 m.

Searching for Critical Conditions During Lifeboat Launching – Simulations

Abstract The article describes numerical simulations of the process of lifeboat launching at the ship’s side. The research aimed at finding the values of ship motion parameters which appear to be most dangerous for people in the lowered lifeboat due to the generated accelerations. The simplified model of ship hull motion adopted at this research stage bases on a superposition of harmonic motions with given amplitudes and periods in six degrees of freedom. The range of the amplitude of motion for each degree of freedom corresponds approximately to that of possible motion of the PANAMAX type ship on the Baltic sea. In total, 120 960 cases of ship hull motion were examined.

Novel Design of an Ocean Wave Power Device

The paper presents a novel device for capturing the energy of sea-waves and the construction of its model for conducting test in a towing-tank. The paper also presents the research program and general analyses on selecting the hull form and systems of anchoring and propulsion. In addition, it includes remarks and observations gathered following initial tests and measurements of the device operating in regular wave conditions.