A novel refrigerant-direct radiant cooling system: Numerical simulation-based evaluation

Split air-conditioners have deficiency in thermal comfort due to draught sensation and fan noise. The existing radiant cooling systems adopt chilled water as circulating medium, resulting low energy efficiency because of the requirement secondary heat exchange. To address these problems, a novel refrigerant-direct (RDRC) system is proposed. Experiments are conducted climate chamber evaluate performance this system. Results show that RDRC terminal surface temperature distributed homogenously has excellent stability. mathematical economic models established model validated with experimental data. effects different structural parameters on performances investigated, then optimized by orthogonal design method. capacity for per exterior area considered objective function initial cost less than 121.1 $ taken constraint condition. indicate fin height 40.0 mm, copper pipe diameter 6.0 spacing mm aspect ratio 0.88 recommended.