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A decline in oil-related revenues challenges Norway to focus on new types of offshore installations. Often, ship-mounted crane systems transfer cargo or crew onto offshore installations such as floating windmills. This project analyzes the motion of a ship induced by an onboard crane in operation using a new theoretical approach to dynamics: the moving frame method (MFM). The MFM draws upon Lie group theory and Cartan's moving frames. This, together with a compact notation from geometrical physics, makes it possible to extract the equations of motion, expeditiously. While others have applied aspects of these mathematical tools, the notation presented here brings these methods together; it is accessible, programmable, and simple. In the MFM, the notation for multibody dynamics and single body dynamics is the same; for two-dimensional (2D) and three-dimensional (3D), the same. Most importantly, this paper presents a restricted variation of the angular velocity to use in Hamilton's principle. This work accounts for the masses and geometry of all components, interactive motor couples and prepares for buoyancy forces and added mass. This research solves the equations numerically using a relatively simple numerical integration scheme. Then, the Cayley-Hamilton theorem and Rodriguez's formula reconstruct the rotation matrix for the ship. Furthermore, this work displays the rotating ship in 3D, viewable on mobile devices. This paper presents the results qualitatively as a 3D simulation. This research demonstrates that the MFM is suitable for the analysis of "smart ships," as the next step in this work. [ABSTRACT FROM AUTHOR]

Deepwater risers are susceptible to vortex-induced vibrations (VIV) when subjected to currents. When responding at high modes, fatigue damage in the inline (IL) direction may become equally important as the crossflow (CF) components. Accurate calculation of both IL and CF responses is therefore needed. Empirical VIV prediction programs, such as VIVANA "Passano et al. (2016, "VIVANA--Theory Manual Version 4.8," Trondheim, Norway)," SHEAR7 "(Vandiver, J. K., and Li, L., 2007, "Shear7 v4.5 Program Theoretical Manual," Department of Ocean Engineering, Massachusetts Institute of Technology, Cambridge, MA)," and VIVA "Triantafyllou et al. (1999, "Pragmatic Riser VIV Analysis," Offshore Technology Conference, Houston, TX, May 3-6, Paper No. OTC-10931-MS.)" are the most common tools used by the offshore industry. Progress has been seen in the prediction of CF responses. Efforts have also been made to include an IL load model in VIVANA. A set of excitation coefficient parameters were obtained from rigid cylinder test and adjusted using measured responses of one of the flexible cylinder VIV tests. This set of excitation coefficient parameters is still considered preliminary and further validation is required. Without an accurate IL response prediction, a conservative approach in VIV analysis has to be followed, i.e., all current profiles have to be assumed to be unidirectional or acting in the same direction. The purpose of this paper is to provide a reliable combined IL and CF load model for the empirical VIV prediction programs. VIV prediction using the existing combined IL and CF load model in VIVANA is validated against selected flexible cylinder test data. A case study of a deepwater top tension riser (TTR) has been carried out. The results indicate that VIV fatigue damage using two-dimensional directional current profiles is less conservative compared to the traditional way of using unidirectional current profiles. [ABSTRACT FROM AUTHOR]

This paper presents an analysis of stratification-dependent mean velocity profiles measured in a Norwegian coastal wind climate, and its comparison with models available in the literature. For this purpose, we use 3 years of observations from a 100 m meteorological mast located at the Frøya island (150km west of Trondheim, Norway), equipped with a set of two-dimensional (2D) ultrasonic anemometers. The presented analysis is preceded by a general description of the site wind climate, the atmospheric stratification, the roughness length, and the surface layer height. Finally, the measured wind velocity profile is compared with selected models: the basic power and logarithmic law and the stability-corrected models: stability-corrected logarithmic wind profile, the Panofsky and Dutton model, the Peña boundary layer height corrected model, and the correlation-based Smedman-Högström model. [ABSTRACT FROM AUTHOR]

This paper presents the potential of composting oil wet drill cuttings as a drilling waste disposal option. The potential is substantiated by results from several laboratory and field experiments. Artificially oil wetted drill cuttings were prepared by adding commonly used base oils from Norwegian offshore operations to a representative clay. Degradation of the hydrocarbon components in the oily wet cuttings by vermicomposting was successfully accomplished. The composts were beneficially used as part of growing media for landscape plants; ryegrass, coniferous, and deciduous trees, and the fertilization effect was compared with commercial NPK fertilizers. The plant growth studies showed that the composts produced by treating artificial oily drill cuttings by vermicomposting had considerable fertilizing effect on ryegrass and trees. [ABSTRACT FROM AUTHOR]

Located approximately 120 km offshore, Ormen Lange, with an estimated 400×109 m3 of natural gas, is the second-largest gas discovery on the Norwegian shelf. The water depth is up to 850 m, making Ormen Lange the first deepwater project on the Norwegian continental shelf. The development of Ormen Lange is under shared operatorship between Norsk Hydro and Shell. Ormen Lange's untreated well stream will be transported to shore in two 120 km long, 30 in. diameter pipelines to a processing plant at Nyhamna, Norway. From there, gas will be exported via a 42 in., 1200 km subsea pipeline (Langeled) to Easington at the east coast of the UK. The pipelines have to pass over the Storegga slide edge, which rises 200-300 m toward the continental shelf in very steep slopes, which are also encountered in the nearshore Björnsundet area. The uneven and steep seabed conditions require the use of approximately 2.8×106 tons of rock to support and stabilize the pipelines. The sea bottom conditions on the Norwegian continental shelf are characterized by many outcrops as well as very soft clay deposits. The immediate settlement of the rock supports during installation forms a significant amount of the total required rock volume. In this paper a procedure is presented on how to assess these immediate settlements recognizing four contributing components all being discussed separately. The calculation results are compared with a back analysis, performed during the execution of the Ormen Lange rockworks, proving the suitability of the calculation method. [ABSTRACT FROM AUTHOR]

The global learning initiative at Northeastern University is focused on fostering intercultural communication skills. The Dialogue of Civilization (DOC) program serves as a mechanism to achieve such a goal by offering faculty-led international experiences. In this paper, we have presented a detailed account of a DOC program that took place in Norway. The primary objective of the program was to teach mechanical engineering and bio-engineering students computational skills while stimulating critical thinking about the cultural and social aspects of technology and engineering in Norway. The program focused on two courses: a technical course and a special topics course. The technical course introduced students to finite element analysis, with practical applications and site visits in Norway to enhance experiential learning. In the special topics course, the interplay between modern technologies, like green energy, state policies, and the rights and traditions of the indigenous Sámi people was explored. The course highlighted both the progressive social policies in Norway and the historical discrimination against the Sámi. Student feedback was positive and experiential learning components such as guest lectures and site visits were particularly appreciated. Additional surveys showed that students' self-confidence was higher following the DOC program. In addition, female-identifying students had higher confidence in their future success after completion of this program as compared to their male-identifying counterparts. Our paper is expected to serve as a resource for educators seeking to integrate technical education with intercultural experiences and discussions on social and cultural impacts in engineering., (Copyright © 2024 by ASME; reuse license CC-BY 4.0.)