Assessment and optimization of friction losses and mechanical efficiency in internal combustion engines
- Autores: Antonio José Jiménez Reyes
- Directores de la Tesis: Bernardo Vicente Tormos Martínez (dir. tes.)
- Lectura: En la Universitat Politècnica de València ( España ) en 2022
- Idioma: español
- Tribunal Calificador de la Tesis: José María Desantes Fernández (presid.), Francisco José Jiménez-Espadafor Aguilar (secret.), Hannes Allmaier (voc.)
- Programa de doctorado: Programa de Doctorado en Sistemas Propulsivos en Medios de Transporte por la Universitat Politècnica de València
- Materias:
- Enlaces
- Tesis en acceso abierto en: RiuNet
- Resumen
Currently, the field of light-duty vehicle transport is undergoing a major shift towards decarbonisation. Increasingly, European authorities are restricting emissions of greenhouse gases into the atmosphere from these vehicles. Alternative solutions to fossil fuel propulsion, such as the implementation of electric or hybrid vehicles, are not sufficiently developed to replace internal combustion engine alternatives (ICEs), due to their still high production cost and low infrastructure to meet the demand for electric power.
In this context, the transition towards sustainable and renewable mobility continues to be based on increasing efficiency and reducing fuel consumption in internal combustion engines. An alternative to improving efficiency is the reduction of mechanical frictional losses, or in other words, optimisation of tribology. Tribology in an MCIA is associated with mechanical aspects such as the optimisation of the surface finishes of the different components that make up the engine and the optimisation of the physical, chemical and rheological properties of the oil that makes up the engine. This last solution presents a high benefit/cost ratio, as its implementation does not involve any hardware modification and its implementation is straightforward.
One of the objectives of the Doctoral Thesis is to develop a 1D model that contains the tribological information of an internal combustion engine that cannot be obtained experimentally, which contributes to the understanding and optimisation of mechanical friction losses and saves the experimental cost associated with understanding tribology from an empirical point of view. These parameters range from the oil film thickness between two tribological components to the contribution to friction of the hydrodynamic and roughness components of each friction element. In addition, a quasi-stationary model has been developed to quantify the energy dissipated by friction in a real driving cycle and the associated fuel consumption.
Thus, through this model, solutions ranging from rheologically optimised oils to low roughness surface finishes are implemented, understanding the phenomenology associated with each technology and providing key parameters for the optimisation of the solution. Finally, the savings in terms of fuel consumption that can be achieved with these solutions implemented using the quasi-stationary model in real driving conditions are estimated.
