Nanofluids as Advanced Heat Transfer Fluids for the Next Generation Solar Thermal Energy Systems

Solar Thermal Energy Systems and Nanofluids Research
📌 Dr. Salah is a researcher at CPUT in South Africa, focusing on developing nanofluids as advanced heat transfer fluids to enhance Concentrated Solar Power (CSP) systems.
⚙️ CSP technology has historical roots dating back to Archimedes, with modern applications demonstrating capacities up to 6.3 gigawatts produced globally by July 2022.
🔬 Research focuses on optimizing parabolic trough solar collectors by enhancing the heat transfer fluid, which is central to energy transport efficiency.

Nanofluids Production and Characterization
🧪 Nanofluids are created by adding nanoparticles (single or hybrid) to conventional fluids (like water or ethylene glycol) to boost thermal conductivity, as solids generally have higher conductivity than liquids.
⚡ The Pulsed Laser Ablation in Liquid (PLAL) method is highlighted as a clean, green, and cost-effective technique for scaling up the production of pure nanoparticles compared to chemical reduction/hydrothermal methods.
📈 Experimental results showed that Copper ($\text{Cu}$) nanoparticles produced using a 515 nm laser yielded a 30% enhancement in thermal conductivity at a very low volume fraction of 0.002% in ethylene glycol.

Theoretical Modeling and Simulation
⚛️ Molecular Dynamics (MD) simulations are employed as a crucial virtual laboratory tool to understand and predict the thermophysical properties of nanofluids at the atomic level.
🛠️ MD simulations utilize potentials (like Lennard-Jones for the liquid base and Embedded Atom Model for metallic nanoparticles) derived from Ab initio (quantum mechanical) calculations to model complex interactions accurately.
🔬 Theoretical models, such as the modified Maxwell model incorporating a nanolayer of absorbed solvent molecules, confirmed that nanoparticle size below 10 nm is critical for maximizing enhancement due to high surface energy effects.

Key Points & Insights
➡️ Nanofluids are a key enabler for the next generation of CSP systems, contributing to a decarbonized economy by providing high-efficiency, zero-carbon emission energy production.
➡️ The PLAL technique is highly attractive for commercialization because it produces pure nanoparticles, avoiding extra purification costs associated with chemical synthesis methods.
➡️ Research priority is maximizing thermal enhancement at the lowest possible volume fraction (\text{0.002%} achieved), conserving raw materials for future applications like water desalination and milk pasteurization.
➡️ When synthesizing nanoparticles, the laser wavelength matters: a 515 nm laser produced smaller, more effective nanoparticles (average size $\text{2.5 nm}$) compared to a $1064 \text{ nm}$ laser ($\text{4.8 nm}$), resulting in higher thermal enhancement.

📸 Video summarized with SummaryTube.com on Jan 12, 2026, 21:56 UTC