공랭식 냉각기를 사용한 열에너지저장시스템 및 초임계이산화탄소 발전 사이클 열역학적 분석 = Thermodynamic Analysis of a Thermal Energy Storage System Coupled with a sCO2 Power Cycle Using an Air-Cooled Cooler

국문 초록 (Abstract)

소듐을 저장매체로 하는 열에너지저장시스템은 고온탱크와 저온탱크의 온도차를 크게 운전함으로써 에너지 저장밀도를 높일 수 있다. 본 연구는 이러한 운전조건에 적용할 수 있는 초임계이산화탄소 발전 사이클을 제안한다. 초임계이산화탄소 발전 사이클의 설계 변수에 대한 매개변수 분석을 수행하고 최적화된 열평형을 도출하였다. 열에너지저장시스템의 설치위치에 대한 제약을 없애고 수자원이 부족한 내륙 지역에도 설치가 가능하도록 공랭식 냉각기의 적용성을 평가하였다. 이를 위하여 초임계이산화탄소 발전 사이클의 공랭식 냉각기 설계 코드 개발 및 검증을 수행하였다. 공랭식 냉각기에 대한 설계를 수행하여 최종적으로 공랭식 냉각기의 크기를 도출하고, 이를 적용했을 때 초임계이산화탄소 발전 사이클 효율 변화를 검토하였다.

다국어 초록 (Multilingual Abstract)

Thermal energy storage (TES) systems utilizing sodium as the storage medium can enhance energy storage density by operating under substantial temperature differences between the hot and cold tanks. This study proposes a novel sCO2 Brayton cycle tailored for such operating conditions. A parametric study of the sCO2 design parameters is used to derive the optimized thermal equilibrium. In addition, the study evaluates the applicability of air-cooled coolers, mitigating constraints on the installation location of the TES system and facilitating inland deployment where water is scarce. Consequently, a design code for the sCO2 air-cooled cooler is developed and validated. Furthermore, the sizing of the air-cooled cooler assesses the impact of air-cooled coolers on the efficiency of the sCO2 Brayton cycle.

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