Simultaneous PIV-LIF Measurements With A SCMOS Color Camera Using RuPhen
J. Shah (1,2), C. Mucignat (2), I. Lunati (2), T. Rösgen (1)
(1) Institute of Fluid Dynamics, Department of Mechanical and Process Engineering, ETH Zürich, Switzerland
(2) Laboratory of Multiscale studies in Building Physics, Empa Dübendorf, Switzerland
DOI:
Simultaneous velocity and temperature measurements are important in understanding the heat and momentum transfer in thermal fluid flow applications. PIV measures the displacement of a constellation of tracer particles using cross-correlation to obtain the velocity field, while LIF uses temperature-dependent fluorescence emission to map the intensity to temperature using a calibration. In this work, we present a low-cost PIV-LIF system to simultaneously measure velocity and temperature fields in aqueous flows with a single color camera, a CW laser (λe = 465 nm) and a novel dye RuPhen. The technique can also be extended to 3D LIF/3D2C PIV using a scanning light sheet. We find that the RuPhen dye is well-suited due to its peak absorption in the blue, emission in the red, and a strong temperature-dependent emission with a sensitivity coefficient of -4%/ °C. We also propose a method to use the red and green channels to correct for any laser power fluctuations. We demonstrate the technique by studying the flow past and inside a heated hollow hemisphere in a small water tunnel.
