Análise modal de vibrações de um motor de combustão interna: enfoque em um sistema monocilíndrico de quatro tempos

Abstract

The study of the vibrations of a mechanical system allows the evaluation of extremely influential parameters for its good functioning, allowing to obtain fundamental results to prevent failures or abnormal behavior of this system throughout its useful life. Using this analysis as a starting point, it can be ensure that the structure responsible for the stability and functioning of an alternative engine, for instance, never reaches frequencies that when reached possibly will act destructively on the system, producing excessive wear and fatigue that tend to shorten its useful life. The general objective of the present work is to use a modal analysis of vibrations to verify the operation of a certain internal combustion engine - used in conventional vehicles. So the development of knowledge regarding the operation of these systems is essential, as well as the detailed study of the vibration phenomenon for the theoretical basis of the analysis. As an analysis tool, it is possible to use software that allows the development of structural and dynamic analysis in a simple and intuitive way, basically depending on a good modeling of the system, on techniques related to software manipulation, and on the ability to interpret the responses and operation the same. Therefore, with the aid of these computational tools, it is possible to develop a modeling of a project following the actual dimensions of the system (as the system for the reciprocating motion of an internal combustion engine, analyzed in the present work), as well as performing structural analysis from finite element methods. With the results obtained, it is possible to reach preventive and essential conclusions in the development of a system, avoiding raw material and labor wastes (besides providing a reference of results for the analysis) that allow the safe production of a certain line of products.