Refrigeration TechnologyRefrigeration TechnologyХолодильная техника制冷技术0023-124X2782-4241Eco-Vector63461010.17816/RF634610Original Study ArticlesОригинальные исследованияResearch ArticleExperimental investigation of enhanced CO₂ refrigeration systems at varying operating conditionsЭкспериментальное исследование усовершенствованных систем охлаждения на базе CO₂ при различных условиях эксплуатацииDoerffelChristian
Germany
christian.doerffel@tu-dresden.dehttps://orcid.org/0000-0002-8833-7411BartaRiley B.BartaRiley B.
Germany
christian.doerffel@tu-dresden.dehttps://orcid.org/0000-0003-3031-9138ThomasChristiane
Germany
christian.doerffel@tu-dresden.deHesseUllrich
Germany
christian.doerffel@tu-dresden.deTechnische Universität Dresden Institute of Power Engineering, Bitzer Chair of Refrigeration, Cryogenics and Compressor Technology Dresden090920241909202311241952042607202426072024Copyright ©; 2023, Eco-VectorCopyright ©; 2023, Эко-Вектор2023Eco-VectorЭко-Векторhttps://creativecommons.org/licenses/by-nc-nd/4.0https://freezetech.ru/0023-124X/article/view/634610

The efficiency of a CO₂ refrigeration system depends mainly on the operating conditions and the system design. To increase the energy efficiency, advanced system designs include additional components and their combinations such as parallel compression, ejectors, and expansion machines. For a direct comparison of different system designs, measurements were performed on an advanced CO₂ laboratory refrigeration system at different operating conditions. The system behaviour was investigated at different gas cooler outlet temperatures, varying cooling loads, different evaporation temperatures and amounts of superheating. The results of the measurements performed on a baseline system configuration and advanced system designs are presented. It was observed that the influence of operating conditions is less important for certain measures in terms of efficiency improvement than for others. For each system design, operating conditions were identified under which a particularly advantageous behaviour of the respective measures was found. In the future, this will allow the judgment of the efficiency enhancement of each of different respective features for each individual application.

This article is a translation of the article by Doerffel C, Barta R, Thomas C, Hesse U. Experimental investigation of enhanced CO2 refrigeration systems at varying operating conditions. In: Proceedings of the 9th IIR Conference on the Ammonia and CO2 Refrigeration Technologies. Ohrid: IIF/IIR, 2021.

DOI: 10.18462/iir.nh3-co2.2021.0023 Published with the permission of the copyright holder.

Эффективность системы охлаждения на базе CO₂ в основном зависит от условий эксплуатации и конструкции системы. Для повышения энергоэффективности современные системы включают в себя дополнительные компоненты и их сочетания, например, параллельное сжатие, эжекторы и детандеры. Для прямого сравнения различных конструкций систем были проведены измерения на передовой лабораторной холодильной системе на базе CO₂ при различных условиях эксплуатации. Поведение системы было исследовано при различных температурах на выходе из газоохладителя, различных нагрузках на охлаждение, различных температурах кипения и перегревах. Представлены результаты измерений, выполненных на базовой конфигурации системы и на её усовершенствованных конструкциях. Было замечено, что с точки зрения повышения эффективности влияние условий эксплуатации для одних мероприятий менее значимо, чем для других. Для каждой конструкции системы были определены условия эксплуатации, при которых поведение соответствующих мероприятий было особенно благоприятным. В будущем это позволит судить о повышении эффективности каждой из соответствующих функций для каждой отдельной области применения.

Настоящая статья представляет собой перевод статьи Doerffel C, Barta R, Thomas C, Hesse U. Experimental investigation of enhanced CO2 refrigeration systems at varying operating conditions. In: Proceedings of the 9th IIR Conference on the Ammonia and CO2 Refrigeration Technologies. Ohrid: IIF/IIR, 2021.

DOI: 10.18462/iir.nh3-co2.2021.0023 Публикуется с разрешения правообладателя.

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