Estudo das ondas de pressão formadas na admissão de um motor de combustão interna com a presença de um ressonador

Abstract

Numerical analysis has become a tool of great importance in the search for solutions of increasingly complex engineering problems. This is due both to the technological advancement with respect to the computers’ processing power, and to the techniques used to discretize and solve equations that would be impossible to solve manually and even numerically a few years ago. However, it is neither possible nor advisable to abandon the experimental part, since it is through the experimental results that the numerical results are validated so that from there the computational side can gain more representativeness and credibility. Based on this, this work compares the results obtained through numerical simulation with experimental data of pressure waves in the admission of an internal combustion engine, with the presence of a resonator. These data were found by Hanriot, 2001 and will be used as boundary conditions in the AVL FIRE software and also as a comparison of the numerical model used. AVL FIRE uses the Finite Volume Method, which was better described in the paper. Firstly, a review was done on internal combustion engines, ranging from basic engine operation to some of the equations representative of it. Then there was a brief explanation of Helmholtz's resonator so that, finally, one can approach the numerical and experimental methods used. Numerically, the analysis of pressure waves made in this work generates difficulties to be simulated, because the problem of the compressibility of the fluid in addition to the low values of the speed of the flow can lead to difficulties of convergence of the problem. Fortunately, the numerical methods developed are already capable of solving such problems, but it is still necessary to continue advancing more and more towards discovering new methods or perfecting existing methods, so that solutions are increasingly accurate and methods spend each time less processing time.