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• Introduction to Design and Analysis of Torsional Vibration Dampers in Vehicle Industry

  310-324

  Márk Venczel

  Árpád Veress

  Views:

  343

  The crankshaft of today’s internal combustion engines with high performance output are exposed to harmful torsional oscillations originated from the unbalanced gas and inertial forces. To avoid the fatigue damage of engine components, caused by the undesired vibrations, torsional vibration dampers can be applied. Viscodampers are one type of the torsional vibration dampers, which operational fluid is silicone oil. For cost-effective R&D activities and production, finite element and finite volume numerical discretization methods based calculation techniques must be involved into the engineering work supported by the modern computer technology. The aim of this paper is to provide an insight into the multidisciplinary design and development process of visco-dampers in vehicle industry applications. Four different examples as structural, fatigue, CFD analyses and structural optimization have been introduced in the present work. It turned out from the static structural and fatigue analyses, that the investigated damper has safety factor over the limit for both static structural and fatigue analyses, so it is suitable for the given load conditions. In the structural optimization process 34.36% mass reduction has been achieved. According to the coupled fluid dynamic and heat transfer simulations a rather stagnating air zone evolved between the engine and the damper during the operation, which can cause efficiency reduction of cooling fins mounted onto the housing. In light of the numerical results, the suitable damper position has been determined for the highest heat transfer.

• Parametric Programming Applied to the Optimal Production Structure in Determining

  375-389

  Lajos Nagy

  Margit Csipkés

  Views:

  138

  The agricultural planning often the question arises, how the different input (fertilizer, feed, irrigation, etc) from what to use on a production (land, animals) unit basis, and to what intensity. The input transformational efficiency experiments by setting analysis and evaluation. For example examined the nutrient replenishers fertilization experiments, the effect of nutritional values of the feed on the body weight gain, milk production in animal experiments. The input input efficiency to the external environment (weather, soil conditions, unexpected events), the technology used and the biological factors both influence. The farmer must be chosen in each sector, taking into account the magnitude of these inputs and environmental requirements. The economic optimum is usually trying to approach the sectoral level, which serves as the basis for future planning data. The mathematical programming models using relatively simply and quickly determine the optimal production structure. The models provide the specific resource requirements for, and the limitations of the objective function coefficients are calculated on the basis of sectoral. This becomes a deterministic model, and we can get the appropriate sectoral analyzes outstanding results of production structures. Therefore the relationships within sectors directly incorporate mathematical programming model and corporate interests placed above the interests of the industry to determine the intensity of the sectoral inputs. in their article a fertiliser application example, we present the production structure and the plant production sector fertiliser input of a time optimization, in which the fertilizer for specified sectoral relationships appear in the model objective function.