Screen Printed Thermal Flow Velocity Sensor for Microfluidic Devices Featuring Intrinsic Compensation of Spurious Heat Transfe

摘要

We present a fully screen printed sensor for measuring the flow velocity inside microfluidic chips based on a modified anemometer principle. In contrast to previously reported sensor concepts, this device is designed to automatically compensate for the spurious heat propagation in the substrate and heat conduction in the liquid of interest. Using this approach it is possible to measure the flow velocity of any liquid in a channel directly by means of a single voltage without the need to correct for thermal side effects in a post-processing step. Additionally, fabrication by screen printing allows for integration of the sensor without disturbing the fluid flow.