Presenting an Optimum Design for LNG BOG Re-liquefaction System with an Entropy Generation Minimization Approach

Document Type : Research Paper

Authors

Department of Mechanical Engineering, School of Engineering, University of Qom, Iran

Abstract

In this paper, the investigation of LNG-BOG re-liquefaction system has been performed, and the considerable system is analyzed based on energy conservation law and entropy generation principles. For these analyses, first the conservation of energy analysis is performed, and thermodynamic properties (pressure and temperature) of the cycle are defined. Then, entropy generation values in all components are calculated. The exergy destruction in each component and exergetic efficiency is calculated based on entropy generation values. Finally, NLP multi-objective function of the refrigeration cycle is performed for lowest entropy generation and highest exergetic efficiency. Results show good improvement in LNG-BOG re-liquefaction system characteristics.
 

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