A novel generator–condenser heat exchange coupled auto-cascade absorption refrigeration cycle for low-grade heat utilization
Year: 2026
Type: article
Abstract: To improve the thermodynamic performance of auto-cascade absorption refrigeration (ACAR) systems driven by low-grade heat, a generator–condenser heat exchange coupled cycle (GCX-ACAR) is proposed. Unlike conventional generation-absorber heat exchanger (GAX) systems that recover low-grade absorption heat, the proposed cycle utilizes higher-temperature condensation heat from non-azeotropic refrigerant mixtures, enabling more effective internal heat recovery over a wider operating range. A thermodynamic model of the GCX-ACAR cycle is developed and validated, and the effects of key operating parameters, including high-side pressure, generation temperature, and absorption temperature, are systematically investigated. The results show that the proposed cycle significantly reduces generator heat input while maintaining comparable cooling capacity. A minimum refrigeration temperature of -105°C is achieved and the maximum coefficient of performance (COP) reaches 0.0409, representing an improvement of 45%-114% compared with the conventional ACAR cycle. The enhanced performance is mainly attributed to the efficient utilization of temperature glide during the condensation process of non-azeotropic mixtures and the cascade recovery of condensation and rectification heat. The proposed cycle provides a promising pathway for improving the efficiency of low-grade heat-driven refrigeration systems and has potential applications in LNG precooling and hydrogen liquefaction processes.
Institution: Zhejiang University
Language: English
Subfield: Mechanical Engineering
Field: Engineering
Domain: Physical Sciences
Open Access status: hybrid
Estimated APC paid: $3,000
Award: G9000361797
OpenAlex ID: W7212020276