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A. R. V. Bertrand - One of the best experts on this subject based on the ideXlab platform.

  • Compte rendu partiel du 10e Colloque sur l'Exploitation des Océans, Paris, 20-22 janvier 1982
    EDP Sciences, 2006
    Co-Authors: A. R. V. Bertrand
    Abstract:

    De ce 10e Colloque de l' ASTEO sur l'exploitation des océans (Paris, 20-22 janvier 1982) nous retiendrons les points suivants : - la reconnaissance unanime du rôle primordial joué par le secteur pétrolier dans l'exploitation des richesse océaniques ; - la grande qualité des communications consacrées à l'exploitation pétrolière marine. On retiendra aussi une excellente table ronde consacrée aux sources d'énergie utilisables en propulsion sous-marine et susceptibles de menacer le quasi monopole des classique batteries au plomb. Les batteries évoluées, dont le développement industriel coûterait trop cher en l'absence de débouchés commerciaux suffisants (le marché de la traction électrique automobile paraissant leur échapper), semblent abandonnées. Les piles à combustible à hydrogène et à électrolyte basique (type IFP) et les moteurs Stirling à stockage thermique se présentaient comme les meilleures solutions de remplacement. Mais un conférencier a créé la surprise en présentant un moteur diesel en circuit fermé qui a été certifié par Lloyds Register et dont on parle pour équiper le sous-marin Argyronète

Bertrand A. R. - One of the best experts on this subject based on the ideXlab platform.

  • Compte rendu partiel du 10e Colloque sur l'Exploitation des Océans, Paris, 20-22 janvier 1982 Partial Report on the 10th Symposium on Ocean Exploitation, Paris, 20-22 January 1982
    EDP Sciences, 2006
    Co-Authors: Bertrand A. R.
    Abstract:

    De ce 10e Colloque de l' ASTEO sur l'exploitation des océans (Paris, 20-22 janvier 1982) nous retiendrons les points suivants : - la reconnaissance unanime du rôle primordial joué par le secteur pétrolier dans l'exploitation des richesse océaniques ; - la grande qualité des communications consacrées à l'exploitation pétrolière marine. On retiendra aussi une excellente table ronde consacrée aux sources d'énergie utilisables en propulsion sous-marine et susceptibles de menacer le quasi monopole des classique batteries au plomb. Les batteries évoluées, dont le développement industriel coûterait trop cher en l'absence de débouchés commerciaux suffisants (le marché de la traction électrique automobile paraissant leur échapper), semblent abandonnées. Les piles à combustible à hydrogène et à électrolyte basique (type IFP) et les moteurs Stirling à stockage thermique se présentaient comme les meilleures solutions de remplacement. Mais un conférencier a créé la surprise en présentant un moteur diesel en circuit fermé qui a été certifié par Lloyds Register et dont on parle pour équiper le sous-marin Argyronète. This 10th ASTEO Symposium on Ocean Exploitation (Paris, 20-22 January 1982) concentrated on the following two points: (i) unanimous recognition of the primordial rote played by the petroleum sector in exploiting the wealth contained in the ocean, and (ii) the high quality of the papers devoted to offshore petroleum operations. There was also an excellent round-table discussion devoted to energy sources that can be used for subsea propulsion and that might act as a threat to the quasi-monopoly of conventional lead batteries. So-called sophisticated batteries, for which industrial development would be too expensive in the absence of a sufficient potential market (since the market for electric automotive traction appears to be beyond their reach), appear to have been abandoned. Hydrogen and basic electrolyte fuel cells (IFP type) and thermal-storage Stirling engines appear to be the best alternative solutions. But one speaker created a surprise by describing a closed-circuit diesel engine which has been certified by Llyod's Register and which is being considered for powering the submarine Argyronete

R.d. Oudewortel - One of the best experts on this subject based on the ideXlab platform.

  • Jib Rest Design for Crane Barge Type CB6324 - A New Design Approach
    2015
    Co-Authors: R.d. Oudewortel
    Abstract:

    The Damen Crane Barge type CB6324 is a transhipment barge, designed to operate in harbours, inshore and in near coastal waters worldwide, mainly for the on- and offloading of bulk carriers. In the second generation of this crane barge, optimization of the equipment and overall design is sought, increasing usability of the barge and reducing overall costs. The same is sought in the design of a jib rest, as it is found to be heavy and cost reduction can be realized by reducing weight. Additionally, it is suspected that the jib rest can be hit by the crane grab during operation. The new optimized design is restrained by the need to be able to withstand the load of the crane jib in travel conditions overseas and during its complete operational lifetime. As the barge needs to be able to operate worldwide, identification of Ultimate Limit Loads is key. Lloyds Register provides a conservative method to determine the loads acting on the floating crane barge and its equipment, based on extreme weather conditions. As specific data on the CB6324 is available, a different calculation method is proposed, using motion responses, sea state data and design criteria as an input. The method is based on probability of encountering a sea state, the probability of non-exceedance of a wave in such a sea state, and the operability of the barge, to predict the maximum probable accelerations encountered. Finally, analysis of two first generation crane barges built, show some fatigue crack forming on the jib rests during transport to the operational locations. This signifies an interest of a fatigue analysis and estimation, adding up to three design objectives: A) Finding load cases using modeled motion responses and sea state probability B) Finding a new jib rest design that complies to the criteria set by Damen and with the load cases found with design objective A C) Finding an estimation on the fatigue lifetime on both the first and new generation jib rest For the determination of the accelerations, a tool is developed, which automates the calculations for the maximum expected loads in worldwide near shore operation and transport. The barge motion responses in regular waves are determined and used as the primary input. Secondary input is composed of wave data, direction and spreading. Wind speed, roll, pitch, flooding angles and (bending) stresses in the crane pedestal are used as additional criteria. As an output, it gives an overview of operability over the world, along with a selection of the maximum expected accelerations in the critical directions. Parallel to the load calculations and development of the tool, the design of the new jib rest is made. Starting with a concept and building up detail as more information is brought to light in every calculation step. The resulting design is composed of a 15 ton, hinged, steel A-frame with a weight reduction of approx. 5 ton compared to the first generation. Fatigue prediction shows a significant improvement on the fatigue lifetime, as a transport load case estimates the new design spending approx. 10% of its fatigue lifetime. More weight reduction could be achieved by further research on whether the fr is a reasonable restriction for this barge. The stiffness of the jib rest is increased significantly to comply to this criterium in dropped down position. This weight reduction can only be realised if a less conservative load case calculation method is used, like the one proposed in this thesis.

Oudewortel R.d. - One of the best experts on this subject based on the ideXlab platform.

  • Jib Rest Design for Crane Barge Type CB6324 - A New Design Approach
    2015
    Co-Authors: Oudewortel R.d.
    Abstract:

    The Damen Crane Barge type CB6324 is a transhipment barge, designed to operate in harbours, inshore and in near coastal waters worldwide, mainly for the on- and offloading of bulk carriers. In the second generation of this crane barge, optimization of the equipment and overall design is sought, increasing usability of the barge and reducing overall costs. The same is sought in the design of a jib rest, as it is found to be heavy and cost reduction can be realized by reducing weight. Additionally, it is suspected that the jib rest can be hit by the crane grab during operation. The new optimized design is restrained by the need to be able to withstand the load of the crane jib in travel conditions overseas and during its complete operational lifetime. As the barge needs to be able to operate worldwide, identification of Ultimate Limit Loads is key. Lloyds Register provides a conservative method to determine the loads acting on the floating crane barge and its equipment, based on extreme weather conditions. As specific data on the CB6324 is available, a different calculation method is proposed, using motion responses, sea state data and design criteria as an input. The method is based on probability of encountering a sea state, the probability of non-exceedance of a wave in such a sea state, and the operability of the barge, to predict the maximum probable accelerations encountered. Finally, analysis of two first generation crane barges built, show some fatigue crack forming on the jib rests during transport to the operational locations. This signifies an interest of a fatigue analysis and estimation, adding up to three design objectives: A) Finding load cases using modeled motion responses and sea state probability B) Finding a new jib rest design that complies to the criteria set by Damen and with the load cases found with design objective A C) Finding an estimation on the fatigue lifetime on both the first and new generation jib rest For the determination of the accelerations, a tool is developed, which automates the calculations for the maximum expected loads in worldwide near shore operation and transport. The barge motion responses in regular waves are determined and used as the primary input. Secondary input is composed of wave data, direction and spreading. Wind speed, roll, pitch, flooding angles and (bending) stresses in the crane pedestal are used as additional criteria. As an output, it gives an overview of operability over the world, along with a selection of the maximum expected accelerations in the critical directions. Parallel to the load calculations and development of the tool, the design of the new jib rest is made. Starting with a concept and building up detail as more information is brought to light in every calculation step. The resulting design is composed of a 15 ton, hinged, steel A-frame with a weight reduction of approx. 5 ton compared to the first generation. Fatigue prediction shows a significant improvement on the fatigue lifetime, as a transport load case estimates the new design spending approx. 10% of its fatigue lifetime. More weight reduction could be achieved by further research on whether the fr is a reasonable restriction for this barge. The stiffness of the jib rest is increased significantly to comply to this criterium in dropped down position. This weight reduction can only be realised if a less conservative load case calculation method is used, like the one proposed in this thesis.Floating StructuresODEMechanical, Maritime and Materials Engineerin

George S. Koudis - One of the best experts on this subject based on the ideXlab platform.

  • Airport emissions reductions from reduced thrust takeoff operations
    Transportation Research Part D-transport and Environment, 2017
    Co-Authors: George S. Koudis, Arnab Majumdar, Roderic L. Jones, Marc E.j. Stettler
    Abstract:

    The Sensor Network for Air Quality (SNAQ) at London Heathrow consortium, funded by the UK Natural Environment Research Council (project reference: NE/I007172/1), provided the data that supports this research. G. Koudis received funding from The Lloyds Register Foundation.

  • Airport emissions reductions from reduced thrust takeoff operations
    'Organisation for Economic Co-Operation and Development (OECD)', 2017
    Co-Authors: George S. Koudis, Majumdar A, Jones Roderic, Stettler Mej
    Abstract:

    Given forecast aviation growth, many airports are predicted to reach capacity and require expansion. However, pressure to meet air quality regulations emphasises the importance of efficient ground-level aircraft activities to facilitate growth. Operational strategies such as reducing engine thrust setting at takeoff can reduce fuel consumption and pollutant emissions; however, quantification of the benefits and consistency of its use have been limited by data restrictions. Using 3336 high-resolution flight data records, this paper analyses the impact of reduced thrust takeoff at London Heathrow. Results indicate that using reduced thrust takeoff reduces fuel consumption, nitrogen oxides (NOX) and black carbon (BC) emissions by 1.0–23.2%, 10.7–47.7%, and 49.0–71.7% respectively, depending on aircraft-engine combinations relative to 100% thrust takeoff. Variability in thrust settings for the same aircraft-engine combination and dependence on takeoff weight (TOW) is quantified. Consequently, aircraft-engine specific optimum takeoff thrust settings that minimise fuel consumption and pollutant emissions for different aircraft TOWs are presented. Further reductions of 1.9%, 5.8% and 6.5% for fuel consumption, NOX and BC emissions could be achieved, equating to reductions of approximately 0.4%, 3.5% and 3.3% in total ground level fuel consumption, NOX and BC emissions. These results quantify the contribution that reduced thrust operations offer towards achieving industry environmental targets and air quality compliance, and imply that the current implementation of reduced thrust takeoff at Heathrow is near optimal, considering operational and safety constraints.The Sensor Network for Air Quality (SNAQ) at London Heathrow consortium, funded by the UK Natural Environment Research Council (project reference: NE/I007172/1), provided the data that supports this research. G. Koudis received funding from The Lloyds Register Foundation