A new methodology for predicting the real instantaneous in-cylinder volume in the combustion chamber of a reciprocating internal combustion engine is implemented. The mathematical model developed as part of this methodology, takes into consideration the deformations due to pressure and inertial forces, via a deformation constant adjusted through ANSYS®, using a high-precision CAD model of a SOKAN SK-MDF300 engine. The deformation constant was obtained from the CAD model using the computational tool ANSYS® and the pressure data was obtained from the engine running at three regimes: 1500, 2500, and 3500 rpm. The results were compared with previous models reported in the literature, showing that the deformation constant obtained has a smaller variation among cycles, which leads to a more precise value of the mechanical deformations. Furthermore, to have a more accurate model of the instantaneous volume variation, a factor taking into consideration the lubricant film behavior is introduced to calculate volumetric variation due to geometrical clearances. The influence of the introduced volumetric variation was evaluated through a process of combustion diagnosis, evidencing the improvement in the predictive capacity of thermodynamic modeling and, therefore, the correct prediction of heat release rate.

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Atmospheric contaminants from marine-industrial environments could cause corrosion damage on steel A36 usually used in equipment and machinery. Therefore, it is desirable to study the corrosion phenomena in different micro-environments and formulate adequate protection measures. In this study, three micro-environments were selected and categorized according to ISO-12944-2 standard as C5-I and C5-M. Four multilayer-coating schemes were used on each exposure site to evaluate their performance. Corrosion products were analyzed using XRD, raman and UV-Vis techniques. The results showed that the best system was composed of a flake-filled-epoxy/polyamides/epoxy-siloxane. The results confirmed the influence of atmospheric contaminants on overall behavior from different location.