Diseño y validación de un modelo computacional que permita evaluar el cumplimiento de la norma QCCJT003-2014 de sistemas de escape del modelo M4 para Ciauto Ambato

Abstract

For the design and validation of the exhaust system of the vehicle model M4 of the GREAT WALL brand, section included between the pre-muffler, several stages were suggested: the lifting of plans and applications of reverse engineering, then, to digitize the system geometry of CAD software and to obtain the virtual model for its later analysis through the computational fluid dynamics (CFD), using the software ANSYS-FLUENT. The input parameters for the CFD model were taken directly from the installations of the CIAUTP S.A. assembly company, which were: velocity, temperature and volumetric flow of the combustion gases, measured at the exit of the catalyst and in three main phases of engine operation: slingshot, measurement and full load. After entering the necessary parameters to perform the simulation of the CFD model, it was possible to visualize the trajectories of the combustion gases and the critical points; then the exhaust system validation was performed through the comparison of results obtained by the CFD model and by analytical calculation against the actual values taken at the exit of the exhaust system. In addition, the leakage and leakage tests established in QCJT003-2014 were used to determine the reliability of the system. By means of the comparison of obtained errors in the three methods, it was possible to evaluate that the system complies with the standard, so the model used in the M4 vehicle is reliable.