| Resumo: |
The determination of trawls shapes and tensions is a very complex problem. At this time only the static aspect has been considered, the trawl being placed into a uniform current. Three types of difficulties have been met : - Firstly, the hydrodynamic behaviour of the meshes is not well known ; - Secondly, a net is a complete flexible structure with no own shape unless submitted to the action of external forces, but so we are facing an actual " fluid-structure interaction" problem ; - Thirdly, a flexible reticulate structure is made of an anisotropie and discontinus material. ln this paper, the net studied is a trawl for which, the only parameters known are the drawing and the characteristics of the cables which link it to the trawler. The method that we propose to determine the shape and the tensions in the net consists in writing the equilibrium equations at each knot of the net and resolve this system by an iterative method.
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