Exergy analysis on the storage performance of the sensible heat storage unit

J. Ocean Eng. Technol. 1988;2(1):176-182.

현열 축열조의 성능에 관한 엑서지 해석

김시범,권순석

동아대학교 기계공학과,동아대학교 기계공학과

Keywords: thermal energy, exergy, exergy storage, entropy generation, sensible heat storage

핵심용어: 축열, 엑서지, 엑서지 저장, 엔트로피 생성, 현열축열

Abstract

The exergy analysis on the heat storage performance of the senible heat storage unit which consists of the heat storage material in the concentric annulus and the hot fluid flowing through the inner tube is performed. Heat transfer characteristics which are necessary for the performance of the exergy analysis is obtained from the energy balance equations and the second law of thermodynamics. As the index of heat storage performance, the exergy lossnumber $N_{s}$, and exergy storage ratio from the concepts of the second law of thermodynamics are defined.
Results
are ovtained for the grometry of the storage unit, the Biot number Bi, ambient temperature $T_{o}$ as parameters. From these results the exergy storage ratio can be considered as the efficiency of the hat storage unit and is introduced as a guide to design.