Highly efficient desiccant-coated heat exchanger-based heat pump to decarbonize rail transportation

Shao, Zhao (author), Wang, Z. G. (author), Poredoš, Primož (author), Ge, T. S. (author), Wang, Ruzhu (author)

In the rail sector, air conditioning accounts for 30% of the total operational energy consumption, thus, it is crucial to enhance the efficiency of air conditioning units (ACUs) to reduce overall energy consumption. Traditional ACUs for train vehicles usually have a low coefficient of performance (COP), often less than 2, because of condensation-based dehumidification and a consequent reheating process and also the restricted spaces to install ACUs on the rooftop of the cabinet. Herein, we present a novel ACU with an integrated structural design that uses desiccant-coated heat exchangers (DCHEs) coupled with heat pumps, providing comfortable air conditioning on the metro or high-speed trains. This approach provides a direct method for reducing the air temperature and humidity simultaneously, thus realizing the decoupling of temperature and humidity treatments on a single heat exchanger. Using this design, experimental results show that the proposed system can improve the COP by ∼40% under standard conditions compared with existing ACUs (2.5 vs. 1.8). In addition, the proposed system achieves the highest COP of 2.8 under Shenzhen ground conditions (high humidity and temperature conditions) and exhibits high adaptability to various climate zones. The application of the DCHE-based system in the rail sector can significantly contribute to the decarbonization of the sector and make rail transportation sustainable and ready for a green transformation.

• Language: English
• Keywords: heat pumps, sorption materials, desiccant coated heat exchangers, air-conditioning, rail sector
• Work type: Article
• Typology: 1.01 - Original Scientific Article
• Organization: FS - Faculty of Mechanical Engineering
• Publication status: Published
• Publication version: Author Accepted Manuscript
• Year: 2023
• Number of pages: 11 str.
• Numbering: Vol. 271, art.127014
• PID: 20.500.12556/RUL-154505
• UDC: 621.577
• ISSN on article: 1873-6785
• DOI: 10.1016/j.energy.2023.127014
• COBISS.SI-ID: 185939971
• Publication date in RUL: 19.02.2024

Record is a part of a journal

• Title: Energy
• Publisher: Elsevier Science
• ISSN: 1873-6785
• COBISS.SI-ID: 15306011

Secondary language

• Language: Slovenian
• Keywords: toplotne črpalke, energetska učinkovitost, sorpcijska sredstva, desikativni prenosniki toplote, železniški promet

Projects

• Funder: Other - Other funder or multiple funders
• Funding programme: National Natural Science Foundation of China
• Project number: 51336004

• Funder: Other - Other funder or multiple funders
• Funding programme: National Natural Science Foundation of China
• Project number: 51922070