Non-wetted thermal micro flow sensor

This paper proposes the micro liquid flow sensor for microreactor applications. The standout feature of the developed micro flow sensor is its high resistance to corrosive liquid by making all the wetted surface of the micro flow sensor of glass and placing the sensing elements non-wetted. The micro flow sensor is made by MEMS process. The numerical simulation by 3D-FEM analysis is carried out in order to design and evaluate the micro flow sensor. The normalized difference of temperature is introduced in order to realize the wide flowrate range thermal micro flow sensor. From the experimental evaluation with water, the developed micro flow sensor shows the following performance results. The flowrate range is from 1 muL/min to 200 muL/min, measurement accuracy is plusmn5% of reading, and zero drift is less than 0.2 muL/min/90 days. These results indicate that the micro flow sensor has good performance for micro plant applications.