Effect of laser irradiation on thermal conductivity of ZnO nanofluids

This work examines a laser particle fragmentation process to enhance the thermal conductivity of nanofluids. A Q-switched Nd:YAG laser is employed to change the size of the suspended ZnO nanoparticles in water. The influence of laser irradiation on the suspended particles is analyzed by transmission electron microscopy and absorption spectroscopy. The thermal conductivity of the nanofluid is measured by the transient hot-wire method. The results show that laser irradiation leads to partial fragmentation of some particles. However, the partial size reduction results in substantial enhancement of the thermal conductivity.