Maio 2014 vol. 1 num. 1 - 10th World Congress on Computational Mechanics
Full Article - Open Access.
APPLICATION OF CATENARY CURVES IN HERMETIC COMPRESSOR BASED ON COMPUTATIONAL SIMULATIONS
The techniques used in old buildings, as in suspension bridges, improved in the course of time, generating curved structures that minimize materials and maximize strength. Among the curves used there is the catenary curve, which is an excellent way of building with arches that are supported by the weight and provide stability, flexibility and strength to the structures. The curves catenaries offer better distribution of forces and tensions and its main advantage is that the forces applied in any curve point are divided equally by all her. As a result, structures built in this way have the maximum strength with the least possible use of material. In this work we studied an alternative use in hermetic compressors used in domestic refrigeration, with the objective of reducing material and better thermal efficiency and structural. The catenary curves are applied to the geometry of the cylinder block, keeping the other parts, piston, shaft and connecting rods in their original format. A preliminary study allowed the selection of a viable set of values for the two parameters that determine each catenary. A compressor model was created in the software Claim Space and several simulations were performed in Ansys software for catenary different selected. As criteria for the selection of alternatives sought to maximize the area of heat transfer and minimize the structural tensions. Another important criterion is the minimum thickness of the cylinder to prevent the gas permeability of gray cast iron. Computer simulations showed that the catenary curves produce an efficient temperature distribution, caused by the significant increase in the area. As a result, we obtained an excellent improvement in the rate of heat transfer, so as to minimize the gas temperature at the compressor outlet. Thus the fluid arrives at the condenser with a lower temperature, improving the efficiency of the cooling system. In evaluating the stress simulations showed small variations in the structures, showing the applicability of the catenary in thermomechanical equipment. In addition, there was a noticeable reduction in volume and mass in the compressor cylinder block, to ensure the sustainable use of raw materials. The changes suggested in this work may represent savings in the industry compressors that can be reversed to consumers of household coolers and also industrial.
Palavras-chave: Catenary, Compressor, Simulations,
-  Adair R.P., Qvale E. B., and Pearson, J. T., "Instantaneous Heat Transfer to the Cylinder Wall in Reciprocating Compressors". International Compressor Engineering Conference. Paper 86, 1972.
-  Andreu, A., Gil, L., Roca, P., “A new deformable catenary element for the analysis of cable net structures”. Computers and Structures. P. 1882-1890, 2006.
-  Becerra J.A., Jimenez F.J., Torres M., Sanchez D.T., Carvajal E., “Failure Analysis of Reciprocating Compressor Crankshafts”. Engineering Failure Analysis.Volume 18, 2011.
-  Brok S. W., Touber S., and der Meer J. S. Van, "Modeling of Cylinder Heat Transfer - Large Effort, Little Effect?”. International Compressor Engineering Conference. Paper 305, 1980.
-  Cavallini A., Doretti L., Longo G. A., Rossetto L., Bella B., and Zannerio A., "Thermal Analysis of a Hermetic Reciprocating Compressor" International Compressor Engineering Conference. Paper 1160, 1996.
-  Fagotti F., Todescat M. L., Ferreira R. T. S., and Prata A. T., "Heat Transfer Modeling in a Reciprocating Compressor". International Compressor Engineering Conference. Paper 1043, 1994.
-  Ferreira, E. L. L., “Análise de sistema de válvulas automáticas de compressores alternativos”. Dissertação de Mestrado, Departamento de Engenharia Mecânica, EMC/UFSC,2006.
-  Hermes C.J., “Uma metodologia para a simulação transiente de refrigeradores domésticos”. Tese (Doutorado em Engenharia Mecânica) – Universidade Federal de Santa Catarina, 2006.
-  Longo G.A., Gasparella A., “Unsteady Sate Analysis of the compression cycle of a hermetic reciprocating compressor”. International Journal of Refrigeration. Volume 26, 2003.
-  Mangonon, P. L., “The principles of materials selection for engineering desing”.1ed. New Jersey. Prentice Hall,1999
-  Mansur, S. S., “Simulação numérica do funcionamento de compressores herméticos alternativos considerando as pulsações de gás”. Dissertação de Mestrado, Departamento de Engenharia Mecânica, EMC/UFSC,1986.
-  Prasad, B. G. S. S., “Heat Transfer in Reciprocating Compressors – A Review”. International Compressor Engineering Conference. School of Mechanical Engineering, Purdue University, 1998.
-  Todescat M.L., Fagotti F., Prata A.T., Ferreira R.T.S., Thermal energy analysis in reciprocating hermetic compressors. In: Proceedings of Purdue Int. Compressor Conference, Lafayette, IN, USA. p. 1419–28, 1992.
-  Valipour, H. R., Foster, S. J., “Finite element modelling of reinforced concrete framed structures including catenary action”. Computers and Structures. P. 529-588, 2010.
-  Weinstock R., Calculus of Variations. 2ed. New York: Dover Publications page 30, 1974.
Almeida, C. F.; Paredes, B. M.; Melo, J. V.; Pinto, L. T.; "APPLICATION OF CATENARY CURVES IN HERMETIC COMPRESSOR BASED ON COMPUTATIONAL SIMULATIONS", p. 2003-2013 . In: In Proceedings of the 10th World Congress on Computational Mechanics [= Blucher Mechanical Engineering Proceedings, v. 1, n. 1].
São Paulo: Blucher,
ISSN 2358-0828, DOI 10.5151/meceng-wccm2012-18637
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