Thermodynamic analysis and heat exchanger calculations of transcritical high-temperature heat pumps

Zhao, A.; Pecnik, Rene; Peeters, J.W.R.

doi:10.1016/j.enconman.2024.118172

Thermodynamic analysis and heat exchanger calculations of transcritical high-temperature heat pumps

Title

Thermodynamic analysis and heat exchanger calculations of transcritical high-temperature heat pumps

Author

Zhao, A. (TU Delft Energy Technology)
Pecnik, Rene (TU Delft Energy Technology)
Peeters, J.W.R. (TU Delft Energy Technology)

Date

2024

Abstract

Heating in industrial processes is responsible for approximately 13% of greenhouse gas emissions in Europe. Switching from fossil-fuel based boilers to heat pumps can help mitigate the effect of global warming. The present work proposes novel high-temperature transcritical heat pump cycles targeted at heating air with a mass flow rate of 10 kg/s up to 200 °C for spray drying processes. Four low-GWP refrigerants, R1233zd(E), R1336mzz(Z), n-Butane, and Ammonia are considered as the candidate working fluids. The pressure ratio of the compressor is optimized to achieve a maximum coefficient of performance (COP) for the four working fluids. A shell & tube heat exchanger is considered as the gas cooler. Using a generalized version of the ϵ-NTU method, the gas cooler is sized and a second law analysis is conducted. Striking a balance between the first- and second-law performance and size of the gas cooler, the R1233zd(E) transcritical heat pump cycle with a COP of 3.6 is judged to be the most promising option.

Subject

Heat pump
Low-GWP refrigerants
Second law analysis
Transcritical

To reference this document use:

http://resolver.tudelft.nl/uuid:f7d604b6-cb03-43be-8091-743dd2ccbe3f

DOI

https://doi.org/10.1016/j.enconman.2024.118172

ISSN

0196-8904

Source

Energy Conversion and Management, 303

Part of collection

Institutional Repository