engleski

Decomposition Method as a New Type of Second Law Analysis of the Combustion Process at Internal Combustion Engines

This paper presents a new method of thermodynamic analysis of a combustion process in internal combustion engine. It can be compared to exergy analyses, which by definition gives exergy changes of the cylinder content during the whole process in the engine. In doing so, only the availability and its losses are calculated. It is irrelevant for these analyses whether the full availability of the fuel burnt during some portion of the process can or cannot be realised as pΔV-work. The method presented in this paper gives not only the availability loss in each elementary step of the whole process in the engine, but also the insight in how big is part of burnt fuel availability, during an elementary piston motion, which cannot even theoretically be realised as pΔV work. This method also demonstrates how this – in engine unrealisable work – influences the increase of the realisable part during the process that follow. Method is based on decomposition of a complex real process to so call elementary processes equivalent to the real one. Practical application of decomposition method favour antecedence plotting of special u-s diagrams for combustion products.

internal combustion engine; second law analysis; availability; u-s diagram; decomposition method

nije evidentirano