Transactions of the Korean Society of Mechanical Engineers B (대한기계학회논문집B)

The Korean Society of Mechanical Engineers (대한기계학회)
권호 표지
DOI QR코드

DOI QR Code

Optimal Analysis of Irreversible Carnot Cycle Based on Entransy Dissipation

엔트랜시 소산에 기반한 비가역 카르노 사이클의 최적 해석

  • Kim, Kyoung Hoon (Dept. of Mechanical Engineering, Kumoh Nat'l Institute of Technology)
  • 김경훈 (금오공과대학교 기계공학과)
  • Received : 2016.08.04
  • Accepted : 2016.11.27
  • Published : 2017.02.01
Download PDF
⟨ Previous Next ⟩

Abstract

The concept of entransy has been proposed recently as a potential heat transfer mechanism and could be useful in analyzing and optimizing the heat-work conversion systems. This work presents an entransy analysis for the irreversible Carnot cycle by systematic balance formulations of the entransy loss, work entransy, and entransy dissipations, which are consistent with exergy balances. Additionally, several forms of system efficiency are introduced based on entransy for the appreciation of the optimal system performance. The effects of the source temperature and irreversible efficiencies on the optimal conditions for system efficiencies are systematically investigated for both dumping and non-dumping cases of used source fluid. The results show different trends in entransy efficiencies when compared to the conventional efficiencies of energy and exergy, and represent another method to assess the effective use of heat source in power generation systems.

최근 들어 열전달 포텐셜에 해당하는 엔트랜시 개념이 제안되었으며 이는 열-일 변환 시스템의 해석이나 최적화에 유용하게 사용될 수 있다. 본 논문에서는 비가역 카르노 사이클에 대해 엑서지 균형방정식 해석과 대응해서 체계적인 엔트랜시 손실, 일 엔트랜시, 엔트랜시 소산의 개념에 기반한 엔트랜시 해석을 수행한다. 또한 시스템의 최적 성능을 나타내기 위해서 엔트랜시에 기반한 몇 가지 형태의 시스템 효율을 도입한다. 한번 사용된 열원이 추가적으로 사용되는 경우와 그렇지 않은 경우, 즉 덤핑 경우와 비덤핑인 경우에 대해 시스템 효율의 최적 조건에 대한 열원온도나 비가역 효율의 영향을 체계적으로 조사한다. 해석 결과는 엔트랜시에 의한 효율은 전통적인 에너지나 엑서지에 기반한 효율과는 다른 경향을 보여주며, 이는 열동력 시스템에서 또 다른 열원의 효과적인 사용 방법을 제시한다.

Keywords

References

  1. Guo, Z. Y., Zhu, H. Y. and Liang, X. G., 2007, "Entransy-a Physical Quantity Describing Heat Transfer Ability," Int. J. Heat Mass Transfer, Vol. 50, pp. 2545-2556. https://doi.org/10.1016/j.ijheatmasstransfer.2006.11.034
  2. Cheng, X. T., Liang, X. G. and Guo, Z. Y., 2011, "Entransy Decrease Principle of Heat Transfer in an Isolated System," Chin. Sci. Bull., Vol. 56, pp. 847-854. https://doi.org/10.1007/s11434-010-4328-4
  3. Cheng, X. T. and Liang, X. G., 2013, "From Thermomass to Entransy," Int. J. Heat Mass Transfer, Vol. 62, pp. 174-177. https://doi.org/10.1016/j.ijheatmasstransfer.2013.02.063
  4. Chen, Q., Liang, X. G. and Guo, Z. Y., 2013, "Entransy Theory for the Optimization of Heat Transfer - a Review and Update," Int. J. Heat Mass Transfer, Vol. 63, pp. 65-81. https://doi.org/10.1016/j.ijheatmasstransfer.2013.03.019
  5. Xu, M., "The Thermodynamic Basis of Entransy and Entransy Dissipation," Energy, Vol. 36, pp. 4272-4277.
  6. Liu, W., Liu, Z. C., Jia, H., Fan, A. W. and Nakayama, A., 2011, "Entransy Expression of the Second Law of Thermodynamics and its Application to Optimization in Heat Transfer Process," Int. J. Heat Mass Transfer, Vol. 54, pp. 3049-3059. https://doi.org/10.1016/j.ijheatmasstransfer.2011.02.041
  7. Cheng, X. T. and Liang, X. G., 2013, "Discussion on the Entransy Expressions of the Thermodynamic Laws and Their Applications," Energy, Vol. 56, pp. 46-51. https://doi.org/10.1016/j.energy.2013.04.061
  8. Qian, X. and Li, Z., 2011, "Analysis of Entransy Dissipation in Heat Exchangers," Int. J. Therm. Sci., Vol. 50, pp. 608-614. https://doi.org/10.1016/j.ijthermalsci.2010.11.004
  9. Cheng, X., Zhang, Q. and Liang, X., 2012, "Analyses of Entransy Dissipation, Entropy Generation and Entransy-dissipation-based Thermal Resistance on Heat Exchanger Optimization," Appl. Therm. Eng., Vol. 38, pp. 31-39. https://doi.org/10.1016/j.applthermaleng.2012.01.017
  10. Chen, Q., 2013, "Entransy Dissipation-based Thermal Resistance Performance Design and Optimization," Int. J. Heat Mass Transfer, Vol. 60, pp. 156-162. https://doi.org/10.1016/j.ijheatmasstransfer.2012.12.062
  11. Guo, J. and Xu, M., 2012, "The Application of Entransy Dissipation Theory in Optimization Design of Heat Exchanger," Appl. Therm. Eng., Vol. 36, pp. 227-235. https://doi.org/10.1016/j.applthermaleng.2011.12.043
  12. Qian, S, Huang, L., Aute, V., Hwang, Y. and Radermacher, R., 2013, "Applicability of Entransy Dissipation Based Thermal Resistance for Design Optimization of Two-phase Heat Exchangers," Appl. Therm. Eng., Vol. 55, pp. 140-148. https://doi.org/10.1016/j.applthermaleng.2013.03.013
  13. Xu, Y. C. and Chen, Q., 2013, "A Theoretical Global Optimization Method for Vapor-compression Refrigeration Systems Based on Entransy Theory," Energy, Vol. 60, pp. 464-473. https://doi.org/10.1016/j.energy.2013.08.016
  14. Chen, Q., Xu, Y. C. and Hao, J. H., 2014, "An Optimization Method for Gas Refrigeration Cycle Based on the Combination of Both Thermodynamics and Entransy Theory," Appl. Energy, Vol. 113, pp. 982-989. https://doi.org/10.1016/j.apenergy.2013.08.039
  15. Cheng, X. and Liang, X., 2012, "Entransy Loss in Thermodynamic Processes and its Application," Energy, Vol. 44, pp. 964-972. https://doi.org/10.1016/j.energy.2012.04.054
  16. Cheng, X. and Liang, X., 2012, "Heat-work Conversion Optimization of One-stream Heat Exchanger Networks," Energy, Vol. 47, pp. 421-429. https://doi.org/10.1016/j.energy.2012.08.041
  17. Zhou, B., Cheng, X. T. and Liang, X. G., 2013, "Power and Heat-work Conversion Efficiency Analyses for the Irreversible Carnot Engines by Entransy and Entropy," J. Appl. Phys., Vol. 113, 124904. https://doi.org/10.1063/1.4797494
  18. Cheng, X. T. and Liang, X. G., 2013, "Analyses of Entropy Generation and Heat Entransy Loss in Heat Transfer and Heat-work Conversion," Int. J. Heat Mass Transfer, Vol. 64, pp. 903-909. https://doi.org/10.1016/j.ijheatmasstransfer.2013.05.025
  19. Wang, W. H., Cheng, X. T. and Liang, X. G., 2013, "Entropy and Entransy Analyses and Optimizations of the Rankine Cycle," Energ. Convers. Manage., Vol. 68, pp. 82-88. https://doi.org/10.1016/j.enconman.2012.12.020
  20. Kim, K. H. and Kim, K., 2015, "Comparative Analyses of Energy-exergy-entransy for the Optimization of Heat-work Conversion in Power Generation Systems," Int. J. Heat Mass Transfer, Vol. 84, pp. 80-90. https://doi.org/10.1016/j.ijheatmasstransfer.2015.01.002
  21. Han C. H. and Kim, K. H., 2016, "Entransy and Exergy Analysis for Optimization of Heat-Work Conversion with Carnot Cycle," J. Therm. Sci., Vol. 25, pp. 242-249. https://doi.org/10.1007/s11630-016-0856-9
  22. Zhou, B., Cheng, X. T., Wang, W. H. and Liang, X. G., 2015, "Entransy Analyses of Thermal Processes with Variable Thermophysical Properties," Int. J. Heat Mass Transfer, Vol. 90, pp. 1244-1254. https://doi.org/10.1016/j.ijheatmasstransfer.2015.07.037