Thermo-liquid crystal (TLC) thermography for the 3D temperature characterization of liquid microflows

• Applicant: Professor Dr. Christian Joachim Kähler
• Subject Area: Fluid Mechanics
• Term: from 2017 to 2021
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 329301939

The field of microfluidics is growing exponentially as is its impact in modern industrial applications ranging from the pharmaceutical/medical sector, to consumer electronics, reaching all the way to aerospace and large scale machinery. A great amount of such microfluidics applications, involve heat transfer solutions which employ sophisticated microfluidic devices with complex geometries and flow structures. However, all these innovations have been developed in the absence of an experimental time-resolved means of simultaneously characterizing the 3D velocity and temperature fields of the flow that runs through the microfluidic chips. The ability to understand the flow with this degree of precision will empower scientist and engineers to correct mistakes and device failures before they happen and save substantial costs in development of complex designs.The aim of this research project is to further develop the thermo-liquid crystal (TLC) thermography measurement technique in order to materialize the long awaited simultaneous 3D reconstruction of temperature and velocity fields in liquid flows. Over the last few years, the foundation of the method has been laid out, but further improvements in the fabrication of the TLC particles, acquisition hardware and software, color evaluation algorithms and calibration procedures are necessary to bring the technique to the point where flows in real industrial and scientific applications can be measured reliably. Furthermore, critical questions regarding the nature and color response of the TLC materials, which have remained unanswered for many years, will also be assessed but also the time response of their color signal and the effect of strong shear forces on their color will be examined.

• DFG Programme: Research Grants