Analysis of modified CO2 based combined power and ejector-expansion refrigeration cycle with dual evaporators activated by engine exhaust

Yan Zhu; Youcai Liang; Yaling Liang; Bo Kong; Mingzhang Pan; Zongrun Wang; Haiying Deng

doi:10.1080/15435075.2023.2195483

Analysis of modified CO₂ based combined power and ejector-expansion refrigeration cycle with dual evaporators activated by engine exhaust

Yan Zhu, Youcai Liang^*, Yaling Liang, Bo Kong, Mingzhang Pan, Zongrun Wang, Haiying Deng

^*Corresponding author for this work

Chemical Engineering

Research output: Contribution to journal › Article › peer-review

1 Scopus citations

Abstract

In this research, a combined system consisting of a supercritical CO2 Brayton cycle and an ejector-expansion refrigeration cycle with dual evaporators is presented with the aim to harness the engine exhaust heat effectively. Cascade ejectors are adopted to further reduce the destruction caused by the isenthalpic expansion process, which also can be considered as pressure recovery process. Comparative analysis in terms of thermodynamic and economic is performed between the previously reported system and the modified system under the combined power, refrigeration, and freezing mode (mode 1) and combined refrigeration and freezing mode (mode 2). It is found that improvements of 0.57% and 10.22% in exergy efficiency under mode 1 and mode 2 were achieved by the modified system, respectively, and the sum unit cost of product is reduced by 7.72% compared to the basic system. In the optimized condition, cooling capacities of 18.79 kW and 33.80 kW can be provided for refrigerated zone and freezing zone, respectively. And the exergy efficiency and sum unit cost of product of the system are 16.95% and 108.64 $/GJ, respectively, with a dynamic payback period of 4.994 years.

Original language	English
Journal	International Journal of Green Energy
DOIs	https://doi.org/10.1080/15435075.2023.2195483
State	E-pub ahead of print - 2 Apr 2023

Keywords

Waste heat recovery
supercritical carbon dioxide
power and refrigeration cycle
ejector
refrigerated truck applications

Access to Document

10.1080/15435075.2023.2195483

Cite this

@article{b67aac2c76b54aafbd1e80194c902784,

title = "Analysis of modified CO2 based combined power and ejector-expansion refrigeration cycle with dual evaporators activated by engine exhaust",

abstract = "In this research, a combined system consisting of a supercritical CO2 Brayton cycle and an ejector-expansion refrigeration cycle with dual evaporators is presented with the aim to harness the engine exhaust heat effectively. Cascade ejectors are adopted to further reduce the destruction caused by the isenthalpic expansion process, which also can be considered as pressure recovery process. Comparative analysis in terms of thermodynamic and economic is performed between the previously reported system and the modified system under the combined power, refrigeration, and freezing mode (mode 1) and combined refrigeration and freezing mode (mode 2). It is found that improvements of 0.57% and 10.22% in exergy efficiency under mode 1 and mode 2 were achieved by the modified system, respectively, and the sum unit cost of product is reduced by 7.72% compared to the basic system. In the optimized condition, cooling capacities of 18.79 kW and 33.80 kW can be provided for refrigerated zone and freezing zone, respectively. And the exergy efficiency and sum unit cost of product of the system are 16.95% and 108.64 $/GJ, respectively, with a dynamic payback period of 4.994 years.",

keywords = "Waste heat recovery, supercritical carbon dioxide, power and refrigeration cycle, ejector, refrigerated truck applications",

author = "Yan Zhu and Youcai Liang and Yaling Liang and Bo Kong and Mingzhang Pan and Zongrun Wang and Haiying Deng",

year = "2023",

month = apr,

day = "2",

doi = "10.1080/15435075.2023.2195483",

language = "英语",

journal = "International Journal of Green Energy",

issn = "1543-5075",

publisher = "Taylor and Francis Ltd.",

}

TY - JOUR

T1 - Analysis of modified CO2 based combined power and ejector-expansion refrigeration cycle with dual evaporators activated by engine exhaust

AU - Zhu, Yan

AU - Liang, Youcai

AU - Liang, Yaling

AU - Kong, Bo

AU - Pan, Mingzhang

AU - Wang, Zongrun

AU - Deng, Haiying

PY - 2023/4/2

Y1 - 2023/4/2

N2 - In this research, a combined system consisting of a supercritical CO2 Brayton cycle and an ejector-expansion refrigeration cycle with dual evaporators is presented with the aim to harness the engine exhaust heat effectively. Cascade ejectors are adopted to further reduce the destruction caused by the isenthalpic expansion process, which also can be considered as pressure recovery process. Comparative analysis in terms of thermodynamic and economic is performed between the previously reported system and the modified system under the combined power, refrigeration, and freezing mode (mode 1) and combined refrigeration and freezing mode (mode 2). It is found that improvements of 0.57% and 10.22% in exergy efficiency under mode 1 and mode 2 were achieved by the modified system, respectively, and the sum unit cost of product is reduced by 7.72% compared to the basic system. In the optimized condition, cooling capacities of 18.79 kW and 33.80 kW can be provided for refrigerated zone and freezing zone, respectively. And the exergy efficiency and sum unit cost of product of the system are 16.95% and 108.64 $/GJ, respectively, with a dynamic payback period of 4.994 years.

AB - In this research, a combined system consisting of a supercritical CO2 Brayton cycle and an ejector-expansion refrigeration cycle with dual evaporators is presented with the aim to harness the engine exhaust heat effectively. Cascade ejectors are adopted to further reduce the destruction caused by the isenthalpic expansion process, which also can be considered as pressure recovery process. Comparative analysis in terms of thermodynamic and economic is performed between the previously reported system and the modified system under the combined power, refrigeration, and freezing mode (mode 1) and combined refrigeration and freezing mode (mode 2). It is found that improvements of 0.57% and 10.22% in exergy efficiency under mode 1 and mode 2 were achieved by the modified system, respectively, and the sum unit cost of product is reduced by 7.72% compared to the basic system. In the optimized condition, cooling capacities of 18.79 kW and 33.80 kW can be provided for refrigerated zone and freezing zone, respectively. And the exergy efficiency and sum unit cost of product of the system are 16.95% and 108.64 $/GJ, respectively, with a dynamic payback period of 4.994 years.

KW - Waste heat recovery

KW - supercritical carbon dioxide

KW - power and refrigeration cycle

KW - ejector

KW - refrigerated truck applications

U2 - 10.1080/15435075.2023.2195483

DO - 10.1080/15435075.2023.2195483

M3 - 文章

SN - 1543-5075

JO - International Journal of Green Energy

JF - International Journal of Green Energy

ER -