Open Access

ARTICLE

Numerical Study of Multi-Factor Coupling Effects on Energy Conversion Performance of Nanofluidic Reverse Electrodialysis

Hao Li¹, Cunlu Zhao², Jinhui Zhou¹, Jun Zhang³, Hui Wang¹, Yanmei Jiao^1,*, Yugang Zhao^4,5,*
1 School of Physical and Mathematical Sciences, Nanjing Tech University, Nanjing, 211816, China
2 MOE Key Laboratory of Thermo-Fluid Science and Engineering, Xi’an Jiaotong University, Xi’an, 710049, China
3 Key Laboratory of Unsteady Aerodynamics and Flow Control, Ministry of Industry and Information Technology, Nanjing University of Aeronautics and Astronautics, Nanjing, 210016, China
4 Shanghai Key Laboratory of Multiphase Flow and Heat Transfer in Power Engineering, School of Energy and Power Engineering, University of Shanghai for Science and Technology, Shanghai, 200093, China
5 Key Laboratory of Icing and Anti/De-icing, China Aerodynamics Research and Development Center, Mianyang, 621000, China
* Corresponding Author: Yanmei Jiao. Email: ; Yugang Zhao. Email:
(This article belongs to the Special Issue: Heat and Mass Transfer in Renewable Energy Systems: Challenges and Innovations)

Frontiers in Heat and Mass Transfer https://doi.org/10.32604/fhmt.2025.063359

Received 12 January 2025; Accepted 28 February 2025; Published online 27 March 2025

Abstract

Based on the rapid advancements in nanomaterials and nanotechnology, the Nanofluidic Reverse Electrodialysis (NRED) has attracted significant attention as an innovative and promising energy conversion strategy for extracting sustainable and clean energy from the salinity gradient energy. However, the scarcity of research investigating the intricate multi-factor coupling effects on the energy conversion performance, especially the trade-offs between ion selectivity and mass transfer in nanochannels, of NRED poses a great challenge to achieving breakthroughs in energy conversion processes. This numerical study innovatively investigates the multi-factor coupling effect of three critical operational factors, including the nanochannel configuration, the temperature field, and the concentration difference, on the energy conversion processes of NRED. In this work, a dimensionless amplitude parameter s is introduced to emulate the randomly varied wall configuration of nanochannels that inherently occur in practical applications, thereby enhancing the realism and applicability of our analysis. Numerical results reveal that the application of a temperature gradient, which is oriented in opposition to the concentration gradient, enhances the ion transportation and selectivity simultaneously, leading to an enhancement in both output power and energy conversion efficiency. Additionally, the increased fluctuation of the nanochannel wall from s = 0 to s = 0.08 improves ion selectivity yet raises ion transport resistance, resulting in an enhancement in output power and energy conversion efficiency but a slight reduction in current. Furthermore, with increasing the concentration ratio c_H/c_L from 10 to 1000, either within a fixed temperature field or at a constant dimensionless amplitude, the maximum power consistently attains its optimal value at a concentration ratio of 100 but the cation transfer number experiences a monotonic decrease across this entire range of concentration ratios. Finally, upon modifying the operational parameters from the baseline condition of s = 0, c_H/c_L = 10, and ΔT = 0 K to the targeted condition of s = 0.08, c_H/c_L = 50, and ΔT = 25 K, there is a concerted improvement observed in the open-circuit potential, short-circuit current, and maximum power, with respective increments of 8.86%, 204.97%, and 232.01%, but a reduction in cation transfer number with a notable decrease of 15.37%.

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Keywords

Salinity gradient energy; nanofluidic reverse electrodialysis; energy conversion; nanochannel configuration; multi-factor coupling effect

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