scholarly journals Review of the Design and Technology Challenges of Zero-Emission, Battery-Driven Fast Marine Vehicles

2020 ◽  
Vol 8 (11) ◽  
pp. 941
Author(s):  
Apostolos D. Papanikolaou

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.

2020 ◽  
Vol 21 (6) ◽  
pp. 619
Author(s):  
Kostandin Gjika ◽  
Antoine Costeux ◽  
Gerry LaRue ◽  
John Wilson

Today's modern internal combustion engines are increasingly focused on downsizing, high fuel efficiency and low emissions, which requires appropriate design and technology of turbocharger bearing systems. Automotive turbochargers operate faster and with strong engine excitation; vibration management is becoming a challenge and manufacturers are increasingly focusing on the design of low vibration and high-performance balancing technology. This paper discusses the synchronous vibration management of the ball bearing cartridge turbocharger on high-speed balancer and it is a continuation of papers [1–3]. In a first step, the synchronous rotordynamics behavior is identified. A prediction code is developed to calculate the static and dynamic performance of “ball bearing cartridge-squeeze film damper”. The dynamic behavior of balls is modeled by a spring with stiffness calculated from Tedric Harris formulas and the damping is considered null. The squeeze film damper model is derived from the Osborne Reynolds equation for incompressible and synchronous fluid loading; the stiffness and damping coefficients are calculated assuming that the bearing is infinitely short, and the oil film pressure is modeled as a cavitated π film model. The stiffness and damping coefficients are integrated on a rotordynamics code and the bearing loads are calculated by converging with the bearing eccentricity ratio. In a second step, a finite element structural dynamics model is built for the system “turbocharger housing-high speed balancer fixture” and validated by experimental frequency response functions. In the last step, the rotating dynamic bearing loads on the squeeze film damper are coupled with transfer functions and the vibration on the housings is predicted. The vibration response under single and multi-plane unbalances correlates very well with test data from turbocharger unbalance masters. The prediction model allows a thorough understanding of ball bearing turbocharger vibration on a high speed balancer, thus optimizing the dynamic behavior of the “turbocharger-high speed balancer” structural system for better rotordynamics performance identification and selection of the appropriate balancing process at the development stage of the turbocharger.


2021 ◽  
Vol 152 (A2) ◽  
Author(s):  
A G W Williams ◽  
M Collu ◽  
M H Patel

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.


2015 ◽  
Author(s):  
William A. Hockberger

The Quadrimaran was invented in France in the mid-1980s by Daniel Tollet. It was an inspired design and a radical departure from traditional ship design by a man from outside the marine industry unconstrained by industry technical practices and education. Technical experts could see it would entail more structure and subsystems than other high-performance vessels, but its promise was that those penalties would be more than offset by its claimed low power and fuel consumption. A prototype/demonstrator, Alexander, was built in 1990 and operated for five years carrying and impressing many hundreds of riders. Alexander performed beautifully and appeared to bear out what was claimed. Contracts for several Quadrimarans of different sizes came quickly, especially considering how conservative an industry this is. That was significantly due to Tollet's personal charisma and skill in selling riders on the dream of carrying passengers and freight over the water fast and in comfort, yet economically. Great skepticism prevailed in some quarters, especially among naval architects knowledgeable about AMVs (advanced marine vehicles) and early-stage whole-ship design. At technical meetings, one Quadrimaran principal would comment, for example, "Why would you carry freight across the Atlantic at 38 knots on 230,000 horsepower (a reference to the planned Fastship Atlantic TG-770) when you could do it at 60 knots on only 65,000 horsepower?" Listeners would ask how this could be possible, and he would assert again that the Quadrimaran could do it, but would decline to explain. Respected technical people were working with Tollet and his company and becoming convinced of the Quadrimaran's merit. Along with the contracts came engineers with experience in ship detail design and construction (very different from early-stage whole-ship design), or responsibilities for assessing and approving ships for service. Others were with engine and equipment suppliers. Their opinion that there was something unique and special about the Quadrimaran gave it credibility and influenced more people to accept the major claims made for it. Some dismissed the most extreme claims but still accepted the idea that the Quadrimaran was capable of unusually high performance - considerably less than was being claimed, perhaps, but high nevertheless. In hindsight it is clear the skeptics were right. Results never met expectations, nor could they have. In reality, the Quadrimaran has aspects that inherently prevent it from achieving the characteristics and performance its inventor believed attainable. It cannot be built in a commercially useful size and actually perform as intended. Why this is so will be explained. A crucial fact in the Quadrimaran's history is that Daniel Tollet and his close associates believed strongly that naval architects and engineers who had been immersed in working with the existing ship types would be unable to give the Quadrimaran the very different treatment they believed it required. (Their own educations and professional work were nontechnical.) Such people were excluded from the development of Quadrimaran designs, and the belated discovery of many fundamental technical problems can be attributed to this. The company Tollet established had a number of names over the years, and other associated entities were created at times for various purposes. In this paper they are referred to collectively as QIH (Quadrimaran International Holdings) so as not to confuse things unnecessarily. In 2004 QuadTech Marine LLC was established and acquired the Quadrimaran patent (US Patent No. 5,191,849) and related intellectual property from QIH. QuadTech laid out an extensive R&D program to close gaps in the technical background and address identified issues. In the process, additional information on earlier QIH projects and products was obtained and studied, which brought to light problems that significantly compromised the Quadrimaran's prospective performance and utility. The resulting much-reduced set of potential uses and users led the company to effectively stop pursuing Quadrimaran projects after 2009. (Note: The author was Chief Technology Officer for QuadTech Marine during 2006-9, studying the Quadrimaran and planning the R&D.)


2017 ◽  
Vol 25 (51) ◽  
pp. 77-94
Author(s):  
Giovanni Giulio Valtolina ◽  
Marina D’Odorico

Abstract Despite the increasing social impact of unaccompanied migrant minors (UAMs) in many European Union (EU) member states, EU regulations on UAMs are still inadequate and the necessary protection measures are thus insufficient. More specifically, the “best interest of the child”, stated in a large number of international documents, may not be properly guaranteed. In addition, there is often a discrepancy between the rights of migrant children, according to the international legislation, and the actual protection they receive. Moreover, despite the declared aim of reaching a common standard of reception and inclusion, policies and practices across Europe are still very different. The paper attempts to highlight and discuss some critical issues regarding UAMs in Europe. Over and beyond the need for the EU to develop a common framework, greater efforts should be made in order to improve inclusion of UAMs, especially to ensure the management of the phenomenon beyond the current emergency.


In 2005 the European Hematology Association developed the European Hematology Curriculum. This was distributed as a printed booklet and the intention was that junior hematologist could use it for personal competence development. In the EU-funded project H-net this Curriculum has been adapted into the a web environment by using RDF and placed inside a web portfolio system. How this is done is further described in this article. Furthermore, the possibilities of reusing the curriculum in ways that was not initially intended is described, such as describing Learning Resources inside the web-portfolio system with how they relate to different parts of the curriculum. That way a search for learning resources inside the portfolio by using the curriculum is enabled. And, since the medical field of hematology is closely related to other medical fields the design of the web-version of the curriculum was done in a way that builds for possible combination with any other curriculum in another medical field.


Energies ◽  
2021 ◽  
Vol 14 (20) ◽  
pp. 6610
Author(s):  
Raka Jovanovic ◽  
Islam Safak Bayram ◽  
Sertac Bayhan ◽  
Stefan Voß

Electrifying public bus transportation is a critical step in reaching net-zero goals. In this paper, the focus is on the problem of optimal scheduling of an electric bus (EB) fleet to cover a public transport timetable. The problem is modelled using a mixed integer program (MIP) in which the charging time of an EB is pertinent to the battery’s state-of-charge level. To be able to solve large problem instances corresponding to real-world applications of the model, a metaheuristic approach is investigated. To be more precise, a greedy randomized adaptive search procedure (GRASP) algorithm is developed and its performance is evaluated against optimal solutions acquired using the MIP. The GRASP algorithm is used for case studies on several public transport systems having various properties and sizes. The analysis focuses on the relation between EB ranges (battery capacity) and required charging rates (in kW) on the size of the fleet needed to cover a public transport timetable. The results of the conducted computational experiments indicate that an increase in infrastructure investment through high speed chargers can significantly decrease the size of the necessary fleets. The results also show that high speed chargers have a more significant impact than an increase in battery sizes of the EBs.


2004 ◽  
Vol 20 (03) ◽  
pp. 183-187
Author(s):  
Richard Birmingham ◽  
Jon McGregor ◽  
Severine Delautre ◽  
Jean-Claude Astrugue

Due to the congestion of the traditional transport infrastructure across Europe, the EU has developed the EU Common Transport Policy. This policy endorses the use of waterborne craft to ease onshore congestion. In addition to this there have been follow-up measures in the form of "short sea shipping" and lately the concept of "quality shipping" has surfaced to allay concerns arising from the standards of shipping. It is with this backdrop that an increase in demand for high-speed craft (HSC) has occurred. This in turn has created new concerns of how the safety of HSC can be assured when there is such a lack of historical data. To deal with these concerns, there has been a call for new design tools and methodologies to be developed that raise the profile of safety issues from the very beginning of the design process. It was with this in mind that funding was granted for an EU project called Safety at Speed (S@S), the details of which are described in the paper. S@S is made up of 15 partners spread throughout the EU. The partners come from all areas of the marine industry, including universities, designers/builders, class societies, and operators. The project has been split into six research areas. These are collision and grounding, motions, foundering, containment of damage and fire, integration, and case study. The paper is written from the perspective of the integration work package and describes in detail the driving "vision" behind the project. The perceived structure of the project is examined. The problems that the partners have had to overcome are laid out. These problems have led to an evolution of the interrelationships of work packages. The paper goes on to discuss the use of parameters and how their different forms can be incorporated into the design tool with reference to vast fluctuations in quality of input data. Finally, there is a discussion of how the output results from use of the tool, both for risk and cost, can most usefully be presented.


Author(s):  
Jean-Baptiste R.G. Souppez ◽  
Ermina Begovic ◽  
Pradeep Sensharma ◽  
Fuhua Wang ◽  
Anders Rosén

The rules and regulations inherent to the design pressures and scantlings of high-speed powercrafts are numerous, and regularly reviewed. Recently, the new ISO 12215-5:2019 made notable changes to the way high-speed crafts are analysed, including extending the acceleration experienced up to 8 g in certain circumstances. Nevertheless, despite the multiple iterations and variety of regulatory bodies, the seminal work undertaken on planing crafts throughout the 1960s and 1970s remains the foundation of any rule-based design requirement. Consequently, this paper investigates an array of recently published rules though a comparative design case study, the current state-of-the-art across a number of regulations, and the ultimate impact on scantlings. The study reveals that, despite divergence in intermediate calculations and assumptions, similar requirements are ultimately achieved. Eventually, discussion on the comparison undertaken and future trends in high-speed marine vehicles is provided, tackling the relevance of classical planing theory in light of contemporary innovations.


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