Engineering thermodynamics

Solid Desiccant Heat Pump Fresh Air Unit using Composite Silica Gel

  • YANG Tianyu ,
  • GUO Defang ,
  • GE Tianshu
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  • 1. Institute of Refrigeration and Cryogenics, Shanghai Jiao Tong University, Key Laboratory of Power Mechanical Engineering, MOE China, Shanghai 200240, China
    2. Qingdao Haier A/C Electronic Co., Ltd, Qingdao 266101, China

Online published: 2024-07-15

Supported by

The authors acknowledge the financial support from the National Natural Science Foundation of China (No. 51922070). This work was supported by “the Fundamental Research Funds for the Central Universities”.

Copyright

Science Press, Institute of Engineering Thermophysics, CAS and Springer-Verlag GmbH Germany, part of Springer Nature 2024

Abstract

The introduction of fresh air into the indoor space leads to a significant increase in cooling or heating loads. Solid desiccant heat pump fresh air unit which can handle the latent and sensible load of fresh air efficiently have been proposed recently. To improve the performance of the solid desiccant heat pump fresh air unit in the fresh air handling process, in this paper, the application of composite silica gel in a heat pump fresh air unit was investigated. The comparison between silica gel coating (SGC) and composite silica gel coating (CSGC) shows that the adsorption rate and water uptake capacity of CSGC are more than two times higher than those of SGC. An experimental setup for the solid desiccant heat pump fresh air unit was established. The performance of SGC and CSGC was tested in the setup successively. Results show that under summer conditions, compared with the solid desiccant heat pump fresh air unit using silica gel (SGFU), the average moisture removal and COP of the one using composite silica gel (CSGFU) increased by 15% and 30%, respectively. Under winter conditions, compared with SGFU, the average humidification and COP of CSGFU increased by 42% and 17%. With optimal operation conditions of 3 min switchover time and 40 r/s compressor frequency, the COP of CSGFU under summer conditions can reach 7.6. Results also show that the CSGFU and SGFU have higher COP and dehumidification rate under higher outdoor temperature and humidity ratio.

Cite this article

YANG Tianyu , GUO Defang , GE Tianshu . Solid Desiccant Heat Pump Fresh Air Unit using Composite Silica Gel[J]. Journal of Thermal Science, 2024 , 33(4) : 1286 -1300 . DOI: 10.1007/s11630-024-1964-6

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