Estudo teórico em motores térmicos: fundamentos e avanços termodinâmicos para a otimização do desempenho energético

Abstract

This work presents an in-depth theoretical study on heat engines, grounded in the principles of Thermodynamics. We address the historical importance of the field, its applied physical fundamentals, and recent advancements in the pursuit of higher thermal efficiency. To this end, concepts of classical thermodynamic cycles, such as Carnot, Otto, Diesel, Rankine, Brayton, and Stirling, are discussed, focusing on the conversion of thermal energy into mechanical work and the limits imposed by the laws of Thermodynamics. In this context, the impact of irreversibilities (e.g., friction and thermal dissipations) on entropy generation and the consequent limitation of these systems' real efficiency is highlighted. The study also includes modern strategies for optimizing energy efficiency, encompassing loss mitigation through the application of thermal coatings, the refinement of operational cycles, and the employment of high-temperature resistant materials. Furthermore, the implementation of computational modeling tools and the application of Finite-Time Thermodynamics (FTT) are presented as essential bases for the development of more efficient and durable engines. Thus, it is concluded that Thermodynamics plays a crucial role in the optimization of heat engines and that these will continue to be fundamental components for modern society and modern engineering, continuously evolving to face energy efficiency and environmental challenges