Machines. Technologies. Materials.
Vol. 19 (2025), Issue 12, pg(s) 456-459

MACHINES

Thermodynamic Modeling and Matlab-based Simulation of a Stirling Engine for Micro- Scale Power Generation

  • 1 Energy Department, Mechanical Engineering Faculty, Polytechnic University of Tirana, Tirana, Albania

Abstract

The Stirling engine represents one of the most promising technologies for the efficient conversion of thermal energy into mechanical work, due to its ability to operate with almost any heat source and to achieve theoretical efficiencies approaching the Carnot cycle. This article aims to provide a detailed study of the Stirling cycle, the development of a mathematical model, numerical simulation using MATLAB and the analysis of the engine performance as a function of the main thermodynamic parameters, with special emphasis on applications in micro-power generation. A distinctive aspect of this study lies in the comprehensive treatment of the polynomial dependence of specific heat in all thermodynamic processes, enabling a more accurate representation of real gas behavior compared to idealized classical models. The mathematical model is formulated using the fundamental laws of thermodynamics and the ideal gas equation, as well as the well-known Schmidt model for the analytical description of pressure and volume throughout the cycle. A numerical simulation is then performed in MATLAB, where the work per cycle is calculated, p–V and T–s diagrams are generated, and the theoretical efficiency is evaluated for different operating temperatures and pressures. The simulation results show that increasing the temperature difference and average gas pressure significantly increases the mechanical output of the engine and the power output, while an efficient regenerator significantly improves the overall performance and brings the engine closer to Carnot efficiency. The study shows that the Stirling engine has significant potential for sustainable power generation systems, while the developed modeling and simulation framework provides a solid foundation for further experimental development and design optimization.

Keywords

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