Application of a mathematical model for the analysis of the behavior of the otto MCI cycle under manipulation of environmental parameters

Abstract

The objective of bibliographic and experimental research on the behavior of the thermodynamic cycle in internal combustion engines is to verify changes in behavior, using mathematical solutions to analyze changes in values in terms of pressure, volume and rotation of the crankshaft. The power output of a four-stroke gasoline engine with compression in the engine is proportional to an exponent of 1.34 of the polytropic coefficient and the compression ratio. The effects of pressure and temperature variations on the performance of internal combustion engines that operate at different heights above sea level, which is why it was studied taking advantage of the fact that our country Ecuador has many geographical changes, since quantifying the effects of temperature and pressure is vital to establishing the ability to operate spark ignition engines at altitudes much higher than those for which they were designed. The effects of atmospheric conditions showed that temperature dominates pressure and resulted in a power loss and compression drop of around 1.5% for every 100 m increase in altitude. Engine efficiency dropped approximately 1.54 percentage points for every 300 m increase in altitude. The research was captured in Excel for the development of the mathematical model, in which the pressure vs volume diagram graphs, pressure vs angle of rotation of the crankshaft and the dispersion of forces acting on the piston, connecting rod and crankshaft were obtained.