CLC number: TU831.5
On-line Access: 2020-01-04
Received: 2019-06-06
Revision Accepted: 2019-12-22
Crosschecked: 2019-12-27
Cited: 0
Clicked: 3573
Dong-gen Peng, Shun-yi Li, Dan-ting Luo, Yu-ting Fu, Xiao-song Cheng, Yin Liu. Efficiency comparison and performance analysis of internally-cooled liquid desiccant dehumidifiers using LiCl and CaCl2 aqueous solutions[J]. Journal of Zhejiang University Science A, 2020, 21(1): 44-63.
@article{title="Efficiency comparison and performance analysis of internally-cooled liquid desiccant dehumidifiers using LiCl and CaCl2 aqueous solutions",
author="Dong-gen Peng, Shun-yi Li, Dan-ting Luo, Yu-ting Fu, Xiao-song Cheng, Yin Liu",
journal="Journal of Zhejiang University Science A",
volume="21",
number="1",
pages="44-63",
year="2020",
publisher="Zhejiang University Press & Springer",
doi="10.1631/jzus.A1900241"
}
%0 Journal Article
%T Efficiency comparison and performance analysis of internally-cooled liquid desiccant dehumidifiers using LiCl and CaCl2 aqueous solutions
%A Dong-gen Peng
%A Shun-yi Li
%A Dan-ting Luo
%A Yu-ting Fu
%A Xiao-song Cheng
%A Yin Liu
%J Journal of Zhejiang University SCIENCE A
%V 21
%N 1
%P 44-63
%@ 1673-565X
%D 2020
%I Zhejiang University Press & Springer
%DOI 10.1631/jzus.A1900241
TY - JOUR
T1 - Efficiency comparison and performance analysis of internally-cooled liquid desiccant dehumidifiers using LiCl and CaCl2 aqueous solutions
A1 - Dong-gen Peng
A1 - Shun-yi Li
A1 - Dan-ting Luo
A1 - Yu-ting Fu
A1 - Xiao-song Cheng
A1 - Yin Liu
J0 - Journal of Zhejiang University Science A
VL - 21
IS - 1
SP - 44
EP - 63
%@ 1673-565X
Y1 - 2020
PB - Zhejiang University Press & Springer
ER -
DOI - 10.1631/jzus.A1900241
Abstract: internally-cooled dehumidifiers are efficient liquid desiccant dehumidifiers, whose performance is mainly determined by the device structure and operating conditions. Based on energy and mass conservation in the air, solution, and cooling water in the device, mathematical models are built and their theoretical performance is simulated and analyzed in this paper. A novel measure of dehumidification efficiency is introduced to evaluate the performance of internally-cooled dehumidifiers, in which the equilibrium humidity ratio of the inlet solution is calculated according to the minimum temperature in the inlet solution and the cooling water. Numerical simulations show that a counter flow between air and solution is always the most efficient, followed by cross flow, and parallel flow is the least efficient. Cooling water with the same flow direction as the solution performs better than that with a counter flow, with approximately a 5% improvement in efficiency. Compared with CaCl2, the dehumidification efficiency of a LiCl solution is greater by 60%, while its exergy efficiency is less by 16%. dehumidification efficiency can be improved with the number of air-solution heat transfer units (NTUa-s) increasing, and reduced with the air mass flow rate raised. With NTUa-s increasing, exergy efficiency can be improved, and an increase in mass flow rate of cooling water results in a decrease of efficiency. Higher solution concentration and lower inlet temperature of solution and air can achieve both higher dehumidification efficiency and exergy efficiency.
The paper provides a robust analysis and evaluation of ICDs systems. The paper is well written and well presented. The paper provide novel methodology to deal with similar configurations and provide tools for optimization of these systems.
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