- The development of a continuous and reliable cooling method for computer chips is an evolving subject requiring continuous research in both computer science and thermal management. Two-dye laser induced fluorescence (LIF) provides a minimally invasive way to investigate electronics cooling fluid behavior. Dielectric fluids are of particular interest as they allow full contact with the electronics and have low boiling points, opening the door to two-phase cooling applications.
To validate the non-intrusive properties and viability of the application to dielectric fluid, two-dye planar laser induced fluorescence was used to experimentally capture the temperature profile above a horizontal copper surface using PF-5060 as the dielectric working fluid. Natural convection was examined at heat fluxes ranging from 0.16 to 0.76 W/cm2 and ambient temperatures of 20-45°C. A two-color LIF technique with an Nd:YAG laser was used in order to implement an in situ calibration standard. Sulforhodamine 101 is used as the calibration standard as its fluorescent intensity profile is independent of fluid temperature. Rhodamine B, which has a fluorescent intensity profile that does vary with respect to temperature, is compared to that of the in-situ calibration standard. Since the attenuation experienced by the fluorescing light from both dyes is the same as they travel through the same path to reach the camera’s CCD, the ratio of these intensities produced a reliable calibration standard for experimental measurements. A repeatable and unobtrusive method for measuring temperature profiles have been established in the single phase. This validated technique can be carried over to future two-phase and/or heterogeneous mixture studies.