Modelling the hydrodynamic response of a floating offshore wind turbine – a comparative study

This paper summarises the work conducted within the 1st FOWT (Floating Offshore Wind Turbine) Comparative Study organised by the EPSRC (UK) ‘Extreme loading on FOWTs under complex environmental conditions’ and ‘Collaborative computational project on wave structure interaction (CCP-WSI)’ projects. The hydrodynamic response of a FOWT support structure is simulated with a range of numerical models based on potential theory, Morison equation, Navier-Stokes solvers and hybrid methods coupling different flow solvers. A series of load cases including the static equilibrium tests, free decay tests, operational and extreme focused wave cases are considered for the UMaine VolturnUS-S semi-submersible platform, and the results from 17 contributions are analysed and compared with each other and against the experimental data from a 1:70 scale model test performed in the COAST Laboratory Ocean Basin at the University of Plymouth. It is shown that most numerical models can predict similar results for the heave response, but significant discrepancies exist in the prediction of the surge and pitch responses as well as the mooring line loads. For the extreme focused wave case, while both Navier–Stokes and potential flow base models tend to produce larger errors in terms of the root mean squared error than the operational focused wave case, the Navier-Stokes based models generally perform better. Given the fact that variations in the solutions (sometimes large) also present in the results based the same or similar numerical models, e.g., OpenFOAM, the study highlights uncertainties in setting up a numerical model for complex wave structure interaction simulations such as those involving a FOWT and therefore the importance of proper code validation and verification studies

Les chevauchements de Mamirolle et de Gonsans (Doubs)

Abstract Concludes that the overthrusts in the Jurassic terrain of the Mamirolle-Gonsans region, Doubs, France, were produced by north-south tangential pressures and that the Gonsans fault represents an extension of the Mamirolle fault.</jats:p

Etude geologique de la region sud d'Orchamps-Vennes; les chevauchements du Mont-Miroir et du cirque de N.-D.-de-Consolation

Abstract Discusses the structure of the Jurassic-Cretaceous terrain of the southern Orchamps-Vennes region, France, with special reference to a zone of overthrust to which both the Mont-Miroir and Notre-Dame-de-Consolation thrust faults are related.</jats:p

Computer-Assisted Elaboration of Job Histories

AbstractThree ways are proposed to help the occupational physician in constructing a worker’s job history or Curriculum Laboris (CL) with a PC. The quality and, therefore, the usefulness of any job history is greatly conditioned by the method and quality of data collection. The Curriculum Laboris method explained in a previous article has been briefly summarized as a basis of departure. Then, the workers who were submitted to special medical surveillance were considered. After this, the scrolling menu technique was applied in the elaboration of a job history. Finally, the authors show how the representation of company organization by means of a job exposure matrix (JEM) can help to efficiently elaborate job histories.</jats:p

Surveillance of Occupational Risks Using Job-Exposure Matrices

AbstractThis article deals with the problem of surveillance of occupational risks of workers. Computer-assisted elaboration of the job history (JH) for each worker was achieved by means of a job-exposure matrix (JEM) for each company. The final aim of the project is to find correlations between the exposure data of JHs and the health data of corresponding medical records.As a first experiment, some JEMs were computed using rectangular arrays even though it was realized that this simple structure was not really adequate. Later on, the structure of the computerized JEM included the following questions: (1) what types of information are involved; (2) how can the job-exposure correspondence be represented in the computer; (3) what characteristics of a company should be used for the elaboration of a JEM; (4) who is to construct each JEM, and how? This article shows the inadequacy of some occupational names for evoking the appropriate risks, a drawback which can be surmounted if the company organization is included in the JEM. Based on our analysis, several specifications useful for JEM computerization have been suggested.</jats:p