Property Study And Simulation Analysis Of Lubricant Oil Based On Al₂O₃/TiO₂ Nano-composites

Cylinder liner-piston ring was the main source of friction consumption in engine.The friction pair endured lots of thermal load in engine cycle and it could cause the degradation of oil film.Futhermore,it could cause the film's function disappear,the wear increase and the engine shut down.If we could take some ways to improve the lubricating and friction environment and energy utilization inside engine,it may make a big difference in the power and economy properties of engine.A lot of research showed that adding nano materials to lubricating oil can improve the property of oil film and the lubricating environment inside engine.In this thesis,the Al₂O₃/TiO₂ nano-composites were added to oil,and its application value for engine was studied by the way of computer simulation and experiment.This thesis is mainly as follows:?1?In order to study the property of oil,a friction test bench was designed.The Al₂O₃/TiO₂ nano-composites oil was prepared with different surface modifiers to hold its great steady property and the best result with 2%silane coupling agent was proved.The experiment work based on different concentration/proportion/speed/load was conducted to study the change of friction coefficient and wear,and the Al₂O₃/TiO₂ nano-composites oil had better anti-friction property than base oil.The lubrication mechanism was analyzed by the way of 3D profiler and scanning electron microscope,and self-repair film was formed on the friction surface?2?The viscosity and thermal conductivity were measured.Compared with base oil,the Al₂O₃/TiO₂ nano-composites oil had a better viscosity property.Futhermore,its thermal conductivity was improved which indicated the Al₂O₃/TiO₂ nano-composites could improve the thermal conductivity of oil.The model of viscosity and thermal conductivity were got according to experiment result.?3?Put up simulation model of lubricating oil and introduced the thermal parameter model of Al₂O₃/TiO₂ nano-composites oil to study the impact of Al₂O₃/TiO₂ nano-composites on lubricating oil.The results of thicker film thickness,lower friction and power loss was calculated when Al₂O₃/TiO₂nano-composites oil was used in the simulation model.?4?The nano lubricating oil was used in engine test and the impact of Al₂O₃/TiO₂nano-composites on engine power and fuel economy property was studied by the way of motored engine/load property test/speed property test.Both of the properties were improved when the Al₂O₃/TiO₂ nano-composites oil was used in engine.Al₂O₃/TiO₂ nano-composites could improve the anti-wear and friction property of lubricant oil so as to the viscosity and thermal conductivity property.The power and fuel economy property was improved when the Al₂O₃/TiO₂ nano-composites oil was used in engine.