Design And Simulation of Microfluidic Based Carbon Monoxide Gas Sensor Using COMSOL Multiphysics®

The severe problem of Gas Geyser Syndrome calls for the need for a gas sensor that can detect the change in concentration of Carbon Monoxide (CO) gas. The existing gas sensors have limitations of low sensitivity and selectivity; accurate detection of CO is important in the case of Gas Geyser. Microfluidic sensors are generally recommended to improve sensitivity and selectivity. This research work proposes the development of a Microfluidic sensor. The principle working is to measure the change in resistance when the gas is exposed to a sensing layer, and micro-heaters are used to provide temperature uniformity to this layer. The geometry of the structure and the environment for sensing the gas was developed using COMSOL Multiphysics® 5.3a. The Meshing of the geometries was done using a combination of both physics-controlled and user-controlled geometry. To test the sensor, a material was specially created which had the properties of CO gas since it is not readily available in software. After filling the chamber with CO gas, the sensor's response was observed by plotting various parameters to ensure the proper working of the sensor in given environmental conditions. For the supply voltage of (1.2V), the uniform temperature profile was observed to be (640K).