Simultaneous measurement of temperature and velocity using two-colour LIF combined with PIV with a colour CCD camera and its application to the turbulent buoyant plume

Abstract

In this present paper, a method for simultaneously measuring the temperature and the velocity in a planar cross-section of fluid flow with a colour CCD camera is described. This technique combines the laser-induced fluorescence (LIF) and particle image velocimetry (PIV). The temperature is evaluated by the two-colour LIF technique using red and green images of the colour CCD camera, while the velocity is obtained from two sequential blue images by PIV. It is found that the temperature sensitivity of the present technique is almost the same as that of the standard two-colour LIF technique by two monochrome CCD cameras with optimum filter setting, but it provides a simple and convenient system for simultaneous measurement of temperature and velocity in thermal flows. The uncertainty in the temperature measurement is found to be a function of concentration ratios of the fluorescent dyes in the two-colour LIF technique and it increases with an increase in the number of tracer particles for velocity measurement. This technique is successfully applied to the simultaneous measurement of temperature and velocity in the turbulent buoyant plume. The statistical properties of the plume, such as mean and turbulence characteristics of the plume as well as turbulent heat fluxes are evaluated in the initial region of the buoyant plume.

Uncertainty assessment of coupled Digital Image Correlation and Particle Image Velocimetry for fluid-structure interaction wind tunnel experiments

“…PIV has been used in literature for simultaneous measures of temperature and different flow components using different light sources and the corresponding bandpass filters (Post et al, 1994;Funatani et al, 2004). Those applications are particularly interesting in the simultaneous measures of DIC and PIV proposed in the current investigations due to the need to isolate different optical systems.…”

LIF Measurement of the Diluting Effect of Surface Waves on Turbulent Buoyant Plumes

“…In future, a coupling of LIF and Particle Image Velocimetry techniques (such as demonstrated in [16]- [18]) could be used to simultaneously produce instantaneous and time-averaged, full field concentration and velocity maps. This would allow a more complete study of the mechanics of a buoyant plume under the influence of surface waves.…”

Simultaneous imaging techniques for temperature and velocity fields in thermal fluid flows

“…The particle images captured in two sequential field images of time interval 1/60 s are analyzed by cross-correlation algorithm with sub-pixel analysis. For details see Funatani et al (2004).…”

“…There were fewer studies on LIF technique in comparison with the liquid-crystal visualization technique, but it is becoming more popular in recent years due to the development of high performance imaging devices. This technique is extended to the simultaneous Regular Paper measurement of temperature and velocity field in recent years in combination with PIV (Hishida and Sakakibara, 2000;Funatani et al, 2004;Reungoat et al, 2007). It is well known that the accuracy of LIF measurement is improved by the introduction of two-color LIF technique (Sakakibara and Adrian, 1999;Funatani et al, 2004;Hirasawa et al, 2007).…”

“…This technique is extended to the simultaneous Regular Paper measurement of temperature and velocity field in recent years in combination with PIV (Hishida and Sakakibara, 2000;Funatani et al, 2004;Reungoat et al, 2007). It is well known that the accuracy of LIF measurement is improved by the introduction of two-color LIF technique (Sakakibara and Adrian, 1999;Funatani et al, 2004;Hirasawa et al, 2007). This technique eliminates the influence of laser intensity fluctuations, which is a significant error source in the temperature measurement by the single LIF.…”