Simultaneous 2D temperature and velocity measurement using a one-color-camera PLIF method combined with a physically constrained temperature tagging method.

A time-resolved two-color laser induced fluorescence method is proposed for simultaneous 2D temperature and velocity measurements for complex multi-phase flow. A temperature sensitive dye molecule is used for temperature and velocity tagging at the same time. To effectively eliminate the temperature deviation due to image misalignment, which is commonly seen at the multi-phase boundary, a one-color-camera system is proposed that can decrease the temperature deviation from 30°C-50°C to <10 near the two-phase flow boundary with a high contrast ratio (0.

Temporal characterization of heating in femtosecond laser filamentation with planar Rayleigh scattering.

Temporal and spatial evolution of temperature in femtosecond laser filamentation is investigated using planar Rayleigh scattering combined with optical flow algorithm, the corresponding mechanism is analyzed. The temperature increases sharply with a characteristic time of 4.53μs and reach a maximum value of 418 K within 1∼10μs, then decreases slowly to around 300 K with a characteristic time of 136μs.

Nonlinear temperature calibration equation for Rhodamine B in different solutions for wide-temperature-range applications.

In the two-color laser-induced fluorescence (LIF) ratio thermometry approach, accurate temperature calibration is the key for quantitative temperature measurement, especially in wide-temperature-range applications. In this work, the temperature behavior of Rhodamine B in two common solutions (aqueous and ethanol) in a wide temperature range (-30°C-90°C) is studied by spectroscopy methods. According to the spectral and two-color LIF ratio results, a nonlinear fitting method based on Arrhenius equation is presented for a calibration equation.