Análise numérica da influência da geometria do coletor de admissão sobre a eficiência volumétrica em motores ICE

Abstract

This work presents a numerical analysis of the effects of the intake manifold geometry on the performance of an internal combustion engine with spark ignition. The understanding of these effects is extremely important for achieving better engine efficiency and power in order to meet the current requirements regarding the emission of pollutants and the constant desire of the customer to reconcile economy and power. For the accomplishment of the present work the BOOST software of the manufacturer AVL was used. For the analysis, the characteristic torque and power curves were constructed, as well as the volumetric yield curve for different lengths of intake conduits, and the same were compared to each other. Through the theoretical knowledge acquired throughout the course, it was possible to present the advantages, disadvantages and limits of the effects of the intake manifold geometry on the engine performance. It is worth noting that the numerical simulation of the motor behavior is still quite complex, mainly due to its transient nature. Restrictions on air intake, air mixture quality, turbulence level, cylinder intake and exhaust processes, and flame speed during combustion are strongly influenced by the engine operating conditions. The software used has the advantage of great simplicity, speed of response and low computational cost when compared to results of CFD (Computational Fluid Dynamics), allowing preliminary analyzes and comparisons. The results presented in this work show the performance gains obtained through the variation of the length of the conduits, presenting results consistent with the literature.