Probing the thermal resistance of solid-liquid interfaces in nanofluids with molecular dynamics
Iván Carrillo-Berdugo1,2, Javier Navas1, Ricardo Grau-Crespo2
1Department of Physical Chemistry, Faculty of Sciences, University of Cadiz, 11510 Puerto Real, Cádiz, Spain.
The Journal of Chemical Physics
|January 4, 2024
Summary
Interfacial thermal resistance in metal-oil nanofluids was studied. Stronger chemical interactions at the interface reduce thermal resistance, enabling smaller particle sizes for enhanced heat transfer fluids.
Area of Science:
- Materials Science
- Nanotechnology
- Thermodynamics
Background:
- Interfacial thermal resistance (ITR) significantly impacts nanofluid thermal conductivity but remains poorly quantified.
- Nanofluids are promising heat transfer fluids, especially for concentrating solar power applications.
- Understanding ITR is crucial for optimizing nanofluid performance.
Purpose of the Study:
- To investigate the interfacial thermal resistance in metal-oil nanofluids.
- To elucidate the role of chemical interactions in determining ITR.
- To provide insights for designing improved nanofluids for solar thermal applications.
Main Methods:
- Utilized density functional theory (DFT) and molecular dynamics (MD) simulations.
- Analyzed metal-oil nanofluid systems relevant to heat transfer.
- Quantified ITR based on simulated interfacial properties.
Main Results:
- Revealed a direct correlation between chemical interaction strength and ITR: stronger interactions lead to lower ITR.
- Demonstrated that ITR in these metal-oil nanofluids is sufficiently low.
- Showcased that particle size can be reduced without compromising thermal conductivity enhancement.
Conclusions:
- Stronger interfacial chemical interactions are key to reducing thermal resistance in nanofluids.
- Optimized nanofluid design allows for smaller particle sizes, mitigating stability and rheological challenges.
- These findings facilitate the development of more efficient heat transfer fluids for concentrating solar power.
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