Abstract
"2-Color Laser-induced Fluorescence" (2C-LIF) is a novel quantitative temperature measurement method in micro fluidic flow. In a conventional method (1-Color LIF), the undesirable spatio-temporal noise could prevent from quantitative measurement, which is originated from unstable excitation light intensity and channel configuration. In contrast, 2C-LIF can eliminate the undesirable influence using a ratio-metric technique with two fluorescence images, because fluorescence intensities can be approximately a linear function of the excitation light. Therefore, it can obtain quantitative temperature distribution, thus simplify temperature calibration in micro channel. In this study, 2C-LIF was applied to micro-electrophoretic flow, and then local Joule heating by loading high electric field could be visualized according to complicated channel configuration. Consequently, the spatial intensity error could be reduced to about 95% as compared with 1-Color LIF image. The temperature distribution in microchannel was quantitatively measured with high resolution 0.12×0.12μm, temperature sensitivity 1.51%/K with accuracy ±0.45%/K.
