Research Projects

Nanofluids are liquid suspensions with nanoparticles with diameters ranging from 1 to 100 nanometers, which are essential for their enhanced thermal conductivity. However, no models have been able to predict the thermal conductivity of all nanofluids, indicating a lack of understanding of heat transport in nanofluids at molecular-level scales. Self-assembly, or aggregation of nanoparticles, can modify the thermal conductivity of nanofluids through various mechanisms. When dispersed in a fluid, nanoparticles tend to agglomerate due to attractive forces, limiting the effective surface area available for heat transfer. However, self-assembly can also lead to stable structures, such as long-chains, networks, or layers of nanoparticles, which can create more effective heat transfer pathways. This study aims to establish the correlation between self-assembly in nanofluids and thermal conductivity by investigating factors affecting nanoparticle self-assembly and the role of ordered structures on the thermal conductivity of nanofluids. The major challenge is the direct observation of nanoparticle self-assembly due to their nanometre length scales. In-situ liquid phase electron microscopy will be applied, where nanofluids will be encapsulated between electron-translucent 2D material (graphene or SiNx) and observed using a transmission electron microscope. The thermal conductivity of these nanofluids will be tested in an in-house developed thermal conductivity measurement setup. This research will deepen our understanding of the relationship between self-assembly and thermal conductivity in nanofluids, providing guidance for the rational design of high-performance nanofluids for practical applications in energy and heat transfer industries. The results will also be useful in designing and optimizing nanofluids for heat transfer applications.