Vapor generation in a nanoparticle liquid suspension using a focused, continuous laser
This letter discusses experimentation with optically induced phase change in nanoparticle liquid suspensions?commonly termed nanofluids. Four different types of nanofluids at five concentrations were exposed to a ?120?mW, 532 nm laser beam to determine the minimum laser flux needed to create vapor. Laser irradiance was varied between 0?770?W?cm?2. While the experiments were simple, they involved many complex, interrelated physical phenomena, including: subcooled boiling, thermal driven particle/bubble motion, nanoparticle radiative absorption/scattering, and nanoparticle clumping. Such phenomena could enable novel solar collectors in which the working fluid directly absorbs energy and undergoes phase change in a single step.