Dynamic Model Prediction and Validation for Free-Piston Stirling Engines Considering Nonlinear Load Damping

자유피스톤 스털링 엔진의 비선형 부하 감쇠를 고려한 동역학 모델 예측 및 검증

  • Sim, Kyuho (Dept. of Mechanical System Design Engineering, Seoul Nat'l Univ. of Sci. and Tech.) ;
  • Kim, Dong-Jun (Dept. of Mechanical System Design Engineering, Seoul Nat'l Univ. of Sci. and Tech.)
  • 심규호 (서울과학기술대학교 기계시스템디자인공학과) ;
  • 김동준 (서울과학기술대학교 기계시스템디자인공학과)
  • Received : 2015.04.29
  • Accepted : 2015.07.16
  • Published : 2015.10.01


Free-piston Stirling engines (FPSEs) have attracted much attention in the renewable energy field as a key device in the conversion from thermal to mechanical energy, and in the recycling of waste energy. Traditional Stirling engines consist of two pistons that are connected by a mechanical link, while FPSEs are formed as a vibration system by connecting each piston to a spring without a physical link. To ensure the correct design and control of operations, this requires elaborate dynamic-performance predictions. In this paper, we present the performance-prediction methodology using a linear and nonlinear dynamic analytical model considering the external load of FPSEs. We perform linear analyses to predict the operating point of the engine using the root locus technique. Using nonlinear analysis, we also predict the amplitude of pistons by performing numerical integration considering both the linear and nonlinear damping terms of the external load. We utilize the predicted dynamic behavior to predict the engine performance. In addition, we compare the experiment results and existing model predictions for RE-1000 to verify the reliability of the analytical model.


Free-Piston Stirling Engine;Dynamics;Nonlinearity


Supported by : 서울과학기술대학교


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