Fabrication and Evaluation of a Flexible MEMS-Based Microthermal Flow Sensor

Sensors

Myoung-Ock Cho¹  Woojin Jang¹  Si-Hyung Lim² 

[1] Department of Mechanical Systems Engineering, Graduate School, Kookmin University, Seoul 02707, Korea;School of Mechanical Engineering, Kookmin University, Seoul 02707, Korea;

关键词: MEMS;    flexible thermal flow sensor;    microheater;    flow measurement;   

DOI  :  10.3390/s21238153

来源: DOAJ

【 摘 要 】

Based on the results of computational fluid dynamics simulations, this study designed and fabricated a flexible thermal-type micro flow sensor comprising one microheater and two thermistors using a micro-electromechanical system (MEMS) process on a flexible polyimide film. The thermistors were connected to a Wheatstone bridge circuit, and the resistance difference between the thermistors resulting from the generation of a flow was converted into an output voltage signal using LabVIEW software. A mini tube flow test was conducted to demonstrate the sensor’s detection of fluid velocity in gas and liquid flows. A good correlation was found between the experimental results and the simulation data. However, the results for the gas and liquid flows differed in that for gas, the output voltage increased with the fluid’s velocity and decreased against the liquid’s flow velocity. This study’s MEMS-based flexible microthermal flow sensor achieved a resolution of 1.1 cm/s in a liquid flow and 0.64 cm/s in a gas flow, respectively, within a fluid flow velocity range of 0–40 cm/s. The sensor is suitable for many applications; however, with some adaptations to its electrical packaging, it will be particularly suitable for detecting biosignals in healthcare applications, including measuring respiration and body fluids.

【 授权许可】

Unknown