Contribución al estudio experimental de la fricción pistón-camisa en un motor de combustión interna

Abstract

The main focus of this thesis is to study piston assembly friction force in a real engine at low speed, analysing several factors that affect it in which the piston material is included (aluminium and graphite).A thorough experimental research has been carried out in order to measure the piston assembly friction on a real gasoline engine using the IMEP Method (Indicated Mean Effective Pressure) at realistic engine conditions and elements without any major machine modifications.The experiments were planned using the design of experiments methodology. The conclusions obtained are statistically correct and describe the effect of factors and their interactions on piston assembly friction.The effect of piston material was also studied. Friction obtained using aluminium piston was compared with friction obtained using graphite piston. It is found that overall friction losses are reduced using graphite piston under fired conditions.The effect of factors on piston assembly friction depends on both the engine operation and the interaction between variables.