Supermarket application with CO2. New solution and system design for the evaporators overfeeding in cabinet and cold rooms in transcritical booster.

Natural refrigerants are today more and more proposed as a ready to use solution in commercial refrigeration. For this reason there is a constant technological improvement of “green” system, with special reference to CO2 trans critical installations. The key to success is to simplify trans critical technology and enhance efficiency and reliability. This paper present a new solution called FTE (Full Trans critical Efficiency) that has been developed in order to increase reliability and efficiency in a simple design of the system. This solution adds to the system an intermediate liquid receiver located between refrigerated cabinet and the compressors which permits to overfeed the refrigerated loads operating without any superheat and, as consequence, to increase the evaporator temperature and the efficiency. This additional intermediate liquid receiver collects the liquid that’s coming out from the refrigerated loads and delivers the liquid accumulated directly to the frozen loads. FTE is a system solution that can be adopted in all the climates and that increase the efficiency during the whole year. This study has the scope to describe and demonstrate the benefit of the FTE comparing to standard trans critical system. To support the theoretical analysis real consumption of a store installed in South of Europe will be highlighted.

当前，天然制冷剂作为可直接投入使用的解决方案，在商业制冷领域的应用愈发广泛。为此，各类绿色制冷系统的技术迭代持续推进，其中尤以二氧化碳跨临界（trans critical）制冷装置为重点优化对象。此类技术落地的核心关键在于简化跨临界制冷流程，并提升系统的能效与可靠性。本研究提出一种名为FTE（Full Trans critical Efficiency，全跨临界效率系统）的全新解决方案，旨在通过简化系统设计，同步提升运行可靠性与能效水平。该方案在制冷机柜与压缩机之间增设中间储液器，可实现对制冷负载的过供液，使负载能够在无过热度的状态下运行，进而提升蒸发器温度与系统整体能效。该额外增设的中间储液器可收集制冷负载排出的液态制冷剂，并将积存的液态冷媒直接输送至冷冻负载处。FTE系统可适配全气候环境，且能全年提升系统运行效率。本研究旨在阐述并验证FTE系统相较于标准跨临界系统的性能优势。为支撑理论分析，本文将结合欧洲南部某门店的实际运行能耗数据进行实例说明。