A Life-cycle Cost Analysis of the Application of a Hull Vane to an Offshore Patrol Vessel

The consequences of applying a Hull Vane to a Holland Class 108 m Oceangoing Patrol Vessel of the Royal Netherlands Navy were studied by means of a Computational Fluid Dynamics study using Fine/Marine. The effect on the annual fuel consumption was determined by linking the savings percentages at several speeds to the operational speed profile. This paper demonstrates that - from propulsion point of view - a reduction in total fuel consumption can be achieved of 12.5% if a Hull Vane is installed, along with a small modification to the ship’s hull. At the speed at which most fuel is consumed annually (17.5 knots), the total resistance is reduced by 15.3%. Further operational benefits were quantified, such as a reduction of the vertical accelerations at the helicopter deck when sailing in head waves (-13%), a reduction of the turbulent zone just behind the slipway enabling small craft launch and recovery (from 5 to 2.5 meters), an increased range (from 5,000 nautical miles to 5,850 nautical miles at 15 knots) and an increased top speed (from 21.5 knots to 22.1 knots).

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Solar Photovoltaic Optimal Tilt Angles in Public Building

Environmental and Climate Technologies ◽

10.2478/rtuect-2020-0102 ◽

2020 ◽

Vol 24 (3) ◽

pp. 265-277

Author(s):

Valeria Annibaldi ◽

Alessia Condemi ◽

Federica Cucchiella ◽

Marianna Rotilio

Keyword(s):

Inclination Angle ◽

Environmental Performance ◽

Life Cycle Cost ◽

Fossil Fuels ◽

Point Of View ◽

Photovoltaic System ◽

Life Cycle Cost Analysis ◽

Solar Photovoltaic ◽

Renewable Sources

AbstractThe reduction of the consumption of fossil fuels that cause climate change and the encouragement of the use of cleaner renewable sources, appears to be a fundamental objective for achieving the climate aims agreed in Paris. Moreover, the sustainability of the implementation of solutions for energy efficiency in public administration buildings has played a fundamental role in recent years, strengthened also by the regulatory context of energy and environmental policies of European countries. The research fits into this context and it intends to promote a methodology that is able to evaluate the economic and environmental performance of a photovoltaic system applied in a school located in Italy when only the roof inclination angle changes. The economic and environmental performances are evaluated respectively through Life Cycle Cost Analysis and the avoided CO2 emissions. The results show that although the case study does not present the optimal roof inclination angle, there are economic and environmental advantages. Furthermore, the research notes that, considering the characteristics of the photovoltaic system concerned, the optimal roof inclination angle is equal to 40 degrees from an economic and environmental point of view. This methodology could easily support the decision-making process of designers and administrators to make the energy upgrading choices for the promotion of renewable sources. It was applied to a case study, that is a school located in Italy, in the Abruzzo region, in the province of L’Aquila, but it could be easily replicated in other existing public buildings in different locations.

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Use of Life Cycle Cost Analysis and Multiple Criteria Decision Aid Tools for Designing Road Vertical Profiles

Sustainability ◽

10.3390/su11247127 ◽

2019 ◽

Vol 11 (24) ◽

pp. 7127 ◽

Cited By ~ 1

Author(s):

Amara Loulizi ◽

Youssef Bichiou ◽

Hesham Rakha

Keyword(s):

Life Cycle ◽

Cost Analysis ◽

Fuel Consumption ◽

Co2 Emissions ◽

Life Cycle Cost ◽

Decision Aid ◽

Multiple Criteria ◽

Life Cycle Cost Analysis ◽

Current Design ◽

Multiple Criteria Decision Aid

The current design practice for the vertical profile of roads in rolling and mountainous terrains is to follow the existing grades in order to minimize earthwork costs. This means that the only criterion considered during the design phase is the initial cost. It would be preferable to include other criteria that are directly related to sustainability, particularly fuel consumption and CO2 emissions. Therefore, this paper describes a proposed design procedure that starts by finding feasible alternatives with different grades. Then, a microsimulation traffic tool is used to simulate the movement of predicted vehicles (volume and type) over the different alternatives. The microsimulation tool provides reliable estimates of travel times, fuel consumption, and CO2 emissions for the different alternatives. With these data, it is possible to use life cycle cost analysis (LCCA) or multiple criteria decision aid (MCDA) tools to select the “optimal” alternative. The proposed procedure was used on a case study involving a 6-km highway section with different proposed grades ranging from 2% to 8%. Using LCCA and an MCDA tool, it was revealed that the current design alternative is not the optimal alternative in most considered scenarios (various fuel values for LCCA and different “Cost” weights for MCDA).

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Numerical Analysis of Planing Boats in Regular and Irregular Head Waves Using a 2D+t Method

10.5957/fast-2015-057 ◽

2015 ◽

Author(s):

Hendrik Haase ◽

Jan P. Soproni ◽

Moustafa Abdel-Maksoud

Keyword(s):

Numerical Analysis ◽

High Speed ◽

The State ◽

Operating Conditions ◽

Head Waves ◽

Calm Water ◽

Rough Water ◽

Small Craft ◽

Vertical Accelerations ◽

Hydrodynamic Evaluation

A large number of small craft with a demand of high speed are planing vessels (Faltinsen, 2005). Their hulls are designed to plane, a condition, in which the boat's weight is carried mainly by hydrodynamic rather than hydrostatic forces. In order to reach the state of stable planing, planing hulls usually have hard chines, a transom stern and a certain deadrise angle, which is often constant in the aft and becomes larger towards the bow. Smaller deadrise angles are associated with a higher dynamic lift, which is often beneficial for the calm water performance. However, smaller deadrise angles also lead to higher vertical accelerations the crew is exposed to when the boat travels in rough water. To ensure good performance in all operating conditions, a hydrodynamic evaluation of the boat's behaviour both in calm water and in waves is important.

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