On the specific heat capacity enhancement in nanofluids.

Area of Science:

• Materials Science
• Thermodynamics
• Renewable Energy

Background:

• Molten salts are crucial for heat transfer and storage in solar power plants.
• Nanoparticles can enhance the specific heat capacity of base salts, an effect not fully understood.
• Current models often rely on nanolayer assumptions, which are debated.

Purpose of the Study:

• Critically review experimental literature on nanoparticle-enhanced molten salts.
• Discuss existing phenomenological models for specific heat enhancement.
• Propose a new theoretical model to explain the observed effects.

Main Methods:

• Literature review of experimental studies on molten salt nanofluids.
• Analysis of existing phenomenological models.
• Development of a new theoretical model based on long-range nanoparticle interactions.

Main Results:

• Existing models based on nanolayers are insufficient to explain all experimental observations.
• A proposed model considers long-range interfacial layers around nanoparticles.
• This model explains the specific heat capacity maximum observed at higher nanoparticle concentrations.

Conclusions:

• The specific heat enhancement in molten salt nanofluids is likely due to long-range nanoparticle interactions.
• The proposed model offers a new explanation for observed phenomena, particularly the heat capacity maximum.
• Further research is needed to validate this new theoretical framework.