Simultaneous velocity and temperature measurements in turbulent Rayleigh-Bénard convection based on combined Tomo-PIV and PIT

A non-intrusive measurement technique for the simultaneous assessment of the three-dimensional (3D) velocity and temperature �elds in thermal and mixed convection is presented. It is based on the combination of Tomographic Particle Image Velocimetry (Tomo-PIV) and Particle Image Thermometry (PIT) and applied on turbulent Rayleigh-B�enard convection in a water-glycol mixture at Ra = 9 � 109 and Pr = 42. The approach is based on the work ow of Tomo-PIV which provides the particle positions in the fluid volume for PIT. Thermochromic liquid crystals serve as tracer particles and thermometers. Applying this new technique, we measured the instantaneous 3D velocity �elds and the temperature �elds in terms of hue-values