Study on Dynamic Characteristics and Control Strategies of Large Scale Cyclopentane Flooded Organic Rankine Cycle System

ABSTRACT Gas turbine exhaust temperatures typically exceed 500°C, with waste heat recovery significantly improving thermal efficiency. As a mainstream recovery technology, the organic rankine cycle (ORC) utilizes cyclopentane working fluid that has high evaporation temperatures but carries flammability risks. The combined dry and flooded heat exchangers stabilize flow while ensuring superheat, requiring strict liquid level safety. This study investigates dynamic characteristics and control strategies of a flooded ORC system with cyclopentane. Within safe liquid level ranges, pump speed affects system power by merely 0.48% maximum, eliminating the need for regulation; cooling water flow control yields no benefits, while an optimal 0.1 split ratio exists in heat transfer oil. The system maintains safe levels through pump speed adjustment according to operating condition variations and maximizes output power via heat transfer oil split ratio modulation. This study provides theoretical foundations for the operation and control of cyclopentane and flooded ORC systems.