Influence of Implementation of Composite Materials in Maritime Industry on CO2 Emission’s Reduction

The future of the composites market looks attractive with opportunities in the transportation, construction, wind energy, pipe - tank, marine, consumer goods, electrical and electronics, aerospace, and others. The composite materials market is expected to reach an estimated $40.2 billion by 2024 and it is forecast to grow at a CAGR of 3.3% from 2019 to 2024. The composite materials that have started to be used in the production of tourist boats, especially those of the yacht type, have proved in practice the designers' expectations for the great advantages they have brought compared to steel. The performance of the new generation ships of this millennium, will require the ever-increasing use of new and innovative materials, to meet the also growing demands of potential buyers of these vehicles. On the other hand, based on the already sanctioned principles of the European Community for the observance of the norms set for CO2 emissions from maritime transport - (Green shipping) in respect of the Kyoto Protocol on Climate Change, it becomes more necessary to produce marine vehicles that significantly reduce the weight of marine vessels, consequently engine power and fuel consumption by significantly reducing CO2 emissions. This study aims to bring a specific analysis of the impact of composite materials to the CO2 emission’s reduction.

Analysis of propulsion performance of wave-propelled mechanism based on fluid-rigid body coupled model

Wave-propelled mechanisms are applied to propel unmanned marine vehicles such as Wave Glider and wave-powered boats, which can convert wave energy directly into propulsion. In this paper, a fluid-rigid body coupled dynamic model is utilized to investigate the propulsion performance of the wave-propelled mechanism. Firstly, the coupled dynamic model of the wave-propelled mechanism is developed based on relative motion principle by combining rigid body dynamics model and CFD method. Then, the motion responses of wave-propelled mechanism are calculated. The relationship between the propulsion force, heave and pitch motion of hydrofoil are analyzed by using phase diagrams and the actual operation conditions of propulsion mechanism are obtained. Besides, the effects of restoring spring stiffness and wave heights on the propulsion performance are also investigated, and the vortex evolution is illustrated at different moments of movement and different restoring stiffness. These works can be helpful for the design and optimization of different kinds of wave-propelled vehicles.

AERODYNAMIC LIFT FORCES ON MULTIHULLED MARINE VEHICLES

The need for high-speed high-payload craft has led to considerable efforts within the marine transport industry towards a vehicle capable of bridging the gap between conventional ships and aircraft. One such concept uses the forward motion of the craft to create aerodynamic lift forces on a wing-like superstructure and hence, reduce the displacement and skin friction. This paper addresses the specific aerodynamic design of multihull for optimal lift production and shows that significant efficiency can be achieved through careful shaping of a ducted hull, with lift-to-drag ratios of nearly 50 for a complete aerodynamic hull configuration. Further analysis is carried out using a hybrid vehicle stability model to determine the effect of such aerodynamic alleviation on a theoretical planing hull. It is found that the resistance can be halved for a fifty metre, three hundred tonne vehicle with aerodynamic alleviation travelling at 70 knots. Results are presented for a candidate vessel.

STATIC STABILITY OF AERODYNAMICALLY SUPPORTED PLATFORMS MOVING ABOVE WATER

The motion stability is the most important problem of high-speed marine vehicles that utilize aerodynamic support. A simplified analysis and calculations of longitudinal static stability of several basic platforms moving above water are carried out in this study. The analysis is based on the extreme ground effect theory and the assumption of hydrostatic deformations of the water surface. Effects of the underlying surface type, Froude number, and several geometrical parameters on main aerodynamic characteristics, including the static stability margin, are presented. If the underlying surface is water instead of a rigid plane, the static stability worsens for platforms with flat or S-shaped lower surfaces, but it slightly improves for a horizontal platform with a flap. The static stability margin remains positive for S-shaped profiles at sufficiently low Froude numbers, while it is negative for other configurations.

Lightweight Material Optimization of Aquatic Vehicles’ Propeller Based on Fatigue Life Using Hydro Structural Interaction Simulation

Generally, inward and outward effects are huge and prime in the rotating components. Based on the working environments of a rotor, the complexity is increased furthermore. Similarly, this work also deals the complicated problem, which is fatigue life estimation of Marine Vehicles’ propeller for different lightweight materials under given Ocean environments by using Ansys Fluent 16.2. The conceptual design of the ship propeller is modeled with the help of CATIA. Fatigue life estimation on the rotor is a key and complex output of this work, so advanced methodology is mandatory for computation. For that purpose, the following advanced methodology has been implemented for this work, which is Hydro Structural Interaction (HSI) and Moving Reference Frame (MRF) techniques are associated in Computational Fluid Dynamics (CFD). Hydro-Fluid properties such as density and operating pressure are used as per the working vehicles’ environment, which has been easily, defined in Ansys Fluent 17.2. Thus this computational platform is perfect to handle hydrodynamic simulations, even though the gird convergence study is conducted for the better outcomes. In the case of structural simulation, the existing materials such as Aluminium alloy and Stainless Steel are used for fatigue life estimation under HSI loading conditions. Finally, the fatigue life estimation of Marine Vehicles’ propeller is extended for composite materials to compare the life of a rotor. Both the Hydrostatic and Hydrodynamic loading conditions are tested on Aquatic Vehicle’s rotor and thereby the suitable material is chosen and given to the future input for real-time applications.