Improving simultaneous two-color PLIF and PIV temperature and velocity field measurements through a single three-chip color camera

In this paper, we present a simple and cost-efficient single-camera measurement setup for simultaneous temperature and velocity field measurements by two-color Planar Laser Induced Fluorescence (PLIF) and Particle Image Velocimetry (PIV). The camera we used is a three-chip color camera, which utilizes an optical prism to separate the incoming light into the three primary colors: red, green, and blue, each captured by an individual monochromatic camera sensor. Compared to conventional color filter array color cameras, a three-chip camera features significantly less color cross-talk and increased spatial resolution. By illuminating PIV tracers and exciting the fluorescent dyes Rhodamine 110 and RuPhen with a blue 450 nm laser light sheet in water, the camera is capable of recording time-resolved PIV images in the blue color channel, and two-color PLIF images were recorded in the green and red color channels simultaneously. We achieve a high temperature sensitivity of up to 5\,% ∘C⁻¹ 5 % ∘ C - 1 and demonstrate the feasibility of the proposed measurement approach on a Rayleigh–Bénard convection (RBC) experiment at a Rayleigh number Ra = 1.2 × 10⁸ Ra = 1.2 × 10 8 and Prandtl number Pr = 6.1 Pr = 6.1 . The resulting simultaneous temperature and velocity data reveal detaching plumes near the heating and cooling plates and enable a direct analysis of heat transfer. The probability density function (PDF) of the dimensionless heat transfer of a short measurement shows the typical skew toward positive values.