Similarity principle based multi-physical parameter unification and comparison in salinity-gradient osmotic energy conversion

Qinlong Ren, Huangyi Zhu, Kelei Chen, J.F. Zhang and Z.G. Qu

Applied Energy, 2022, vol. 307, issue C, No S0306261921015683

Abstract: Nanofluidic osmotic energy conversion has the potential of directly converting renewable salinity-gradient energy into electricity. Existing research mainly focuses on the ion selectivity and robustness of nanoporous membranes. However, the multi-physical governing parameters of salinity-gradient osmotic energy conversion have never been unified and compared. In the current study, a similarity principle is constructed for ion selective transport in nanofluidic channel through dimensionless analysis, which lays a theoretical foundation for experimental design and data analysis to develop engineering correlations in osmotic energy conversion under a salinity-gradient. The derived dimensionless governing parameters are grouped into four categories with different physical meanings including ion driving source, ion selectivity, ion transport characteristics, and nanoporous membrane configuration. Particularly, a key dimensionless governing parameter named “IonS” is developed for ion selectivity of nanofluidic channel, indicating that the ion selectivity has a positive linear correlation with the nanochannel surface charge density and a negative linear correlation with ion concentration and nanofluidic channel radius. Considering the similarity phenomena in salinity-gradient osmotic energy conversion, future experimental burden is dramatically alleviated. In addition, a sensitivity analysis using Taguchi method is carried out to evaluate the dominance order of multi-physical parameters in salinity-gradient osmotic energy conversion. The ion concentration and nanofluidic channel radius are found to be dominant for maximum output power and energy conversion efficiency because of their significant influences on the thickness of electric double layer and its overlapping degree. The current dimensionless analysis based similarity principle and sensitivity analysis of multi-physical parameters offer an intrinsic insight for ion selective transport in nanofluidic channels, contributing to the development of salinity-gradient osmotic energy conversion for practical applications.

Keywords: Salinity-gradient osmotic energy conversion; Ion selective transport; Similarity principle; Dimensionless analysis; Sensitivity analysis (search for similar items in EconPapers)
Date: 2022
References: View references in EconPapers View complete reference list from CitEc
Citations: View citations in EconPapers (1)

Downloads: (external link)
http://www.sciencedirect.com/science/article/pii/S0306261921015683
Full text for ScienceDirect subscribers only

Related works:
This item may be available elsewhere in EconPapers: Search for items with the same title.

Export reference: BibTeX RIS (EndNote, ProCite, RefMan) HTML/Text

Persistent link: https://EconPapers.repec.org/RePEc:eee:appene:v:307:y:2022:i:c:s0306261921015683

Ordering information: This journal article can be ordered from
http://www.elsevier.com/wps/find/journaldescription.cws_home/405891/bibliographic
http://www.elsevier. ... 405891/bibliographic

DOI: 10.1016/j.apenergy.2021.118312

Access Statistics for this article

Applied Energy is currently edited by J. Yan

More articles in Applied Energy from Elsevier
Bibliographic data for series maintained by Catherine Liu ().