Utilization of a Fifth-Order Model for Analyzing Stirling Oscillators

In this study, for the first time, the design of a free-piston Stirling oscillator (FPSO) using a fifth-order model is addressed. Initially, the free-piston Stirling oscillator is introduced. Then, considering the limited heat transfer coefficient, the fifth-order mechanical model of the oscillator is derived. Subsequently, the design parameters, including the stiffness and mass of the power piston and displacer piston, as well as the cross-sectional area of the rod connecting to the displacer piston, are examined. Then, the design parameters are estimated based on the objectives (a desired frequency between ۷۰ and ۱۰۰ rad/s, and the real value of the dominant closed-loop pole between ۵ and ۱۷) and the fifth-order mechanical model. Nonlinear analysis is then performed to investigate the effects of variations in frequency and the real value of the dominant closed-loop poles on the output power and phase difference between the pistons of the oscillator. The results of this study demonstrate that the use of a fifth-order model offers a more accurate evaluation and analysis of the dynamic behavior of this type of oscillator.

کلیدواژه ها:

free piston Stirling oscillators ، Fifth-Order Model ، renewable energy ، dynamic analysis