Evaluación de tensiones en un tanque cilíndrico para gas natural vehicular

Abstract

El presente trabajo trata sobre la evaluación de tensiones en un tanque cilíndrico para gas natural vehicular, utilizando el método analítico, estudiado por Lamé en 1833, por simulación numérica mediante el uso de un software comercial Cosmo Works, aplicando la técnica de elementos y por el método experimental (strain gages) El objetivo fundamental del estudio es, evaluar las tensiones y deformaciones de un tanque cilíndrico para GNV, para verificar la resistencia de los tanques que se están utilizando en la conversión vehicular. El estudio permitirá determinar el nivel de los esfuerzos y deformaciones para verificar la resistencia de los cilindros para gas natural vehicular a la presión de operación de 20 Mpa. En el país se ha iniciado la conversión vehicular para el uso del gas natural, para lo cual los kits y los tanques de almacenamiento instalados en los vehículos, son importados, los cuales están ingresando al país sin ningún control de calidad. Actualmente, en el Perú, la tecnología sobre la fabricación de los cilindros para altas presiones no se ha desarrollado aún.

This paper deais with the assessment of tensions ¡n a cylindrical tank for natural gas vehicle, using the analytical method, studied by Lamé ¡n 1833, by numerical simulation using a commercial software Cosmos Works, applying the technique of finite element and the experimental method (strain gages). The fundamental objective of the study is to assess the stresses and strains of a cylindrical tank for VNG, to verify the strength of tanks being used in the conversión vehicle. The study will determine the level of effort and deformations to verify the resistance of cylinders for natural gas vehicles operating pressure of 20 MPa. In the country, has begun converting vehicles to use natural gas, for which kits and storage tanks installed in vehicles are imported, which are entering the country without any quality control. Today, in Perú, the technology on the production of cylinders for high pressure has not been developed yet. The method of numerical simulation, has allowed simúlate the behaviour of the cylinder to the pressure of operation with the distribution of tensions with results very similar to the analytical method, with only a discrepancy of 0.3% above the analytical method. However, the FEM, has an advantage that facilitates determine tensions in the curvatura and the neck of the cylinder. And the valúes of tensions determined by the experimental method with respect to the analytical method and the finite element method there is a discrepancy of 9% below, for both cases. In light of the results we can say that the methods used to determine the mínimum thickness are adequate. The cylinders are slightly over-thickness. KEYWORD: Cylinder, tensions, numerical simulation, analytical calculations, experimental method, deformations.