Numerical and Experimental Optimization Study on a Fast, Zero Emission Catamaran (original) (raw)
Related papers
International Shipbuilding Progress
The present work focuses on the application of simulation-based design for the resistance optimization of waterjet propelled Delft catamaran, using integrated computational and experimental fluid dynamics. A variable physics/variable fidelity approach was implemented wherein the objective function was evaluated using both low fidelity potential flow solvers with a simplified CFD waterjet model and high fidelity RANS solvers with discretized duct flow calculations. Both solvers were verified and validated with data for the original hull. The particle swarm optimizer was used for single speed optimization at Fr=0.5, and genetic algorithms were used for multi speed optimization at Fr=0.3, 0.5, and 0.7. The variable physics/variable fidelity approach was compared with high fidelity approach for the bare-hull shape optimization and it showed an overall CPU time reduction of 54% and converged to the same optimal design at Fr=0.5. The multi-speed optimization showed design improvement at Fr=0.5 and 0.7, but not at Fr=0.3 since the design variables were obtained based on sensitivity analysis at Fr=0.5. High fidelity simulation results for the optimized barehull geometry indicated 4% reduction in resistance and the optimized waterjet equipped geometry indicated 11% reduction in effective pump power required at self-propulsion. Verification was performed for the optimized hull form and its reduction in powering will be validated in forthcoming experimental campaign.
Influence of the Hull Shape on the Energy Demand of a Small Inland Vessel with Hybrid Propulsion
Polish Maritime Research
Recently, there has been a significant development of ecological propulsion systems, which is in line with the general trend of environmentally friendly “green shipping”. The main aim is to build a safe, low-energy passenger ship with a highly efficient, emission-free propulsion system. This can be achieved in a variety of ways. The article presents the main problems encountered by designers and constructors already at the stage of designing the unit. The research conducted made it possible to create a design with an effective shape of the hull, with the prospect of an energy-efficient and safe propulsion system with good manoeuvrability. The scope of the research included towing tank tests, recalculation of the results in full-scale objects and a prediction of the energy demand of the propulsion system. The results obtained were compared to indicate power supply variants depending on the hull shape.
Review of the Design and Technology Challenges of Zero-Emission, Battery-Driven Fast Marine Vehicles
Journal of Marine Science and Engineering
The paper deals with a critical review of unique problems and challenges related to the design and technology of zero-emission, battery driven, fast marine vehicles. The uniqueness of the ensuing ship design problem is the request to fit maximum battery capacity and to ensure minimum required power in order to achieve the set operational requirements for high service speed and sufficient range. The high-speed requirement is inherently connected with the request for minimum structural and lightship weight, while the design needs also to comply with set regulatory safety constraints. The underlying research is in the frame of the EU funded project TrAM (Transport: Advanced and Modular) and leads to the development and construction of a physical demonstrator for operation in the Stavanger area in Norway. The paper discusses the incurring critical issues, discusses the feasibility of the concept and concludes on the way ahead.
HULL-FORM OPTIMIZATION OF HIGH SPEED VESSELS WITH RESPECT TO WASH AND POWERING
With the substantial increase of the number, size and service speed of high speed ferries during the last decade, environmental and safety problems related to the impact of ship generated waves on the coastline attracted the interest of Maritime Authorities, ship designers and operators, environmental organizations and local communities. Excessive wash waves may have considerable impact on the marine environment and often they may represent a serious danger to small boats, fishermen and swimmers. To address this problem from the ship design and operational point of view, a hull form optimization procedure for minimum wash and total resistance of high speed vessels has been developed and is herein presented, based on the integration of three software packages: a ship design software package (namely NAPA) is used for the generation of a series of hull forms, based on a number of design variables. Shipflow, a well-known CFD solver is used to perform the hydrodynamic evaluation of each hull form, applying nonlinear potential-flow calculations. The hull form optimization is performed by modeFrontier, a general-purpose optimization software, applying the method of Genetic Algorithms. Results from the application of the above procedure to the design of two vessels, a semi-displacement monohull and a high-speed catamaran are herein presented and discussed.
Progress in Marine Science and Technology
This paper supports decarbonisation in the marine industry by demostrating that a proper design methodology and state of the art technologies can significantly reduce greenhouse gas emissions. The paper demonstrates the possibility of reducing the environmental footprint of Marine High-Speed passenger transportation with innovative propulsion plant designs. The challenging solutions to designing a high-speed hybrid catamaran ferry, that satisfy design criteria and requirements, are presented and applied to a realistic case study. The design process investigated the potential electrification of the vessel to reduce its carbon footprint without compromising function and performance and a quantitative comparison to a conventional propulsion plant was carried out and presented.
Hydrodynamic Analysis in Redesigning a Monohull Passenger Ship into a Catamaran
E3S Web of Conferences, 2021
In line with technological developments, many studies have led to the factors that consider hull shape planning. Therefore, innovations in hull form planning are the primary basis for obtaining a hull that is considered efficient in reducing ship resistance and fuel consumption. This study aims to modify the design of a monohull and transform it into a catamaran while maintaining the total length and Displacement ratio. The ship model used is the Monohull passenger ship with a rounded shape and modified to become a catamaran with a chine shape. The hull chine symmetrical was determined by stagger to the length ratio of S/L 0.3. The hydrodynamic investigations and calculations of models using Computational Fluid Dynamic (CFD). Analysis hydrodynamic on both hulls carried out on the components of total resistance, viscous resistance, friction resistance, and wave resistance with variations of Froude number: 0.3: 0.5: 0.7: 0.9 and 1.2. From the results of the analysis, it is found that ...
A Methodology for the Hull Forms Design of a Passenger Catamaran for the Venice Lagoon
Progress in Marine Science and Technology
The proper definition of the main geometric coefficients and the hull forms of a passenger catamaran must be carried out from the early design stage, due to its strong impact on the resistance, propulsion and the generated wave pattern. This is a primary concern especially in fragile environments, such as the Venice Lagoon, where waves increase erosion phenomena. In this work, a two-phase methodology for the definition of the hull forms of a passenger catamaran, based on both a parametric and CFD analysis, is presented. In the first phase, systematic series data are used to parametrically evaluate possible combinations of main hull dimensions (breadth of the demi hull, deadrise angle), selecting the best one to fit a specific operative scenario (minimisation of required energy). Then, after the validation of mesh parameters with a benchmark hull, the best hull forms are assessed through CFD simulations. To study the interference between the two hulls and select the proper configurat...
Optimization Modelling of a Catamaran Hull Form towards Reducing Ship’s Total Resistance
CFD Letters
Due to the increasing of fuel prices and volatile of environmental regulations, it is a challenge for Naval Architects to design a ship dealing with an optimum ship’s total resistance. The conventional design of catamaran hull has not satisfied yet to reduce the ship’s total resistance. This paper presents a numerical investigation into gaining sufficient reduction of the ship’s total resistance of catamaran through optimizing her hull form. To achieve this research objectives, a numerical optimization modelling coupled with a Computational Fluid Dynamics (CFD) approach has been successfully conducted. Several parameters such as length, beam and draft of catamaran hull have been taken into account towards reducing the ship’s total resistance. Here, the simulation constraints are applied to obtain the optimum dimension, where the length, beam and draft of the catamaran hull were optimized within the range of 1.2 m to 1.5 m, 0.11 m to 0.14 m and 0.07 m to 0.08 m, respectively. In gene...
Energy Conversion and Management, 2019
Shipping has been facing significant challenges due to strict limits imposed by the International Maritime Organization (IMO) to become more environmentally sustainable. In this regard, the use of solar energy, as a viable way to deal with the pollutant emissions caused by ships, has been attracted considerable attention. However, considerable investment costs, high area demands, and low performances of ships equipped with the photovoltaic systems have until recently been some of the significant challenges in the use of solar energy in the shipping industry. This paper proposes a novel method for the optimal performance of ships through the simultaneous optimisation of the hull-propulsion-building integrated photovoltaic (BIPV) system. Using the proposed method, the interaction effects among the ship hull, the BIPV system, and the propulsion system, as well as the impact of the wind and ship speeds on the BIPV system efficiency are considered. Ship operational conditions, including the sunshine duration, the clearness index, the ambient temperature, the latitude of the region, the view factor of the sky to ground, the wind and ship speeds, and the ship lifetime hour are also examined. Moreover, a probabilistic speed profile is employed to avoid a suboptimal design at a single ship speed. The performance of the suggested method is evaluated by designing a planing ship equipped with a waterjet propulsion system that operates in the Karun river, Iran. The non-dominated sorting genetic algorithm (NSGA-II) is used to solve the multi-objective optimisation problem of a planing hull-waterjet-BIPV system. Eight cases are compared to demonstrate the effectiveness and the promise of the proposed approach in different ship design problems with different displacements and BIPV area-to-deck area ratios. The results show the high performance of the adopted approach in cutting operating costs and greenhouse gas (GHG) emissions. Based on the results, the investment costs due to the BIPV system have been recouped within a year in different studied cases and scenarios. It is also found out that the interaction effects among the ship hull, the BIPV system, and the propulsion system are important to ensure the optimal performance of a ship.