Comparative performance analysis of a simplified Curzon-Ahlborn engine

This paper presents a finite-time thermodynamic optimization based on three different optimization criteria: Maximum Power Output (MP), Maximum Efficient Power (MEP), and Maximum Power Density (MPD), for a simplified Curzon-Ahlborn engine that was first proposed by Agrawal. The results obtained for the MP are compared with those obtained using MEP and MPD criteria. The results show that when a Newton heat transfer law is used, the efficiency values of the engine working in the MP regime are lower than the efficiency values (τ) obtained with the MEP and MPD regimes for all values of the parameter τ = T₂/T₁, where T₁ and T₂ are the hot and cold temperatures of the engine reservoirs (T₂ < T₁), respectively. However, when a Dulong-Petit heat transfer law is used, the efficiency values of the engine working at MEP are larger than those obtained with the MP and the MPD regimes for all values of τ. Notably, when 0 < τ < 0.68, the efficiency values for the MP regime are larger than those obtained with the MPD regime. Also, when 0.68 < τ < 1, the efficiency values for the aforementioned regimes are similar. Importantly, the parameter τ plays a crucial role in the engine performance, providing guidance during the design of real power plants.