| Abstract [eng] |
The permeability of the is an especially important factor in determining the power characteristics of diesel internal combustion engines. The exhaust manifold is one of the critical components that determine efficiency of an engine and environmental impact, because it states how efficiently combustion products are expelled from the engine. When it comes to obtaining the best possible results in terms of ecology while at the same time not affecting efficiency of engine, extensive research analyzes are required. The most used are computational models of finite elements, with which help, exhaust manifolds of optimal shape are created. These parts are tested in the further analysis stage, with the help of software simulations. After the completion of the numerical analysis, experimental studies are also carried out, which confirm or supplement the results obtained during the simulation part of analysis. The shape of the collector, the length of the channels, and the presence of sudden changes in the direction of the channel are considered essential factors to create the most efficient exhaust manifold. By accurately analyzing these geometric parameters and their influence, it is possible to develop more efficient and powerful internal combustion engines. Manufacturers of vehicles and their parts make the necessary modifications to internal combustion engines in order to meet the increasingly stringent ecological standards without reducing the power delivered by the engine. In this case, it is often the exhaust manifold part that is chosen to be modified, as it is the component of an engine that can be modified relatively simply. In this project, simulations and experimental studies are carried out for two exhaust manifolds of a selected manufacturer with different shapes and channel lengths. Numerical analysis is performed using the “Solid Works” program, equipment for measuring the pressures at different points of the manifold is designed and manufactured for experimental studies. Exhaust gas pressures are measured at the inlet of each manifold channel and immediately behind the turbine mounting plane. As a result of this research, it was found that when the length of the exhaust manifold channels or the channel geometry changes, the differences in the gas pressures entering and leaving the channels appear. The sudden change in geometry at the manifold gas outlet increases channel pressure differences throughout the manifold, not just only in specific channels. After the numerical analysis of the finite element model and the experimental studies, it was found that the exhaust gas is removed more efficiently by the exhaust manifold with less changes in channel geometry and more even channel lengths. |
