No abstract

We present a novel potentially gas-independent thermal flow sensor chip that contains three two-wire calorimetric flow sensors to measure the flow profile and flow direction inside a tube, and a single-wire flowindependent thermal conductivity sensor which detects the type of the gas through a simple DC voltage measurement. All wires have the same dimensions of 2000 µm in length, 5 µm in width and 1.2 µm in thickness. Four different gases Ar, N2, Ne and He were used for the thermal conductivity measurement and the measured output voltage corresponds very well with a theoretical model.

No abstract

This paper presents a novel gas-independent thermal flow sensor chip featuring three calorimetric flow sensors for measuring flow profile and direction within a tube, along with a single-wire flow independent thermal conductivity sensor capable of identifying the gas type through a simple DC voltage measurement. All wires have the same dimensions of 2000 μm in length, 5 μm in width, and 1.2 μm in thickness. The design theory and COMSOL simulation are discussed and compared with the measurement results. The sensor’s efficacy is demonstrated with different gases, He, N2, Ar, and CO2, for thermal conductivity and thermal flow measurements. The sensor can accurately measure the thermal conductivity of various gases, including air, enabling correction of flow rate measurements based on the fluid type. The measured voltage from the thermal conductivity sensor for air corresponds to a calculated thermal conductivity of 0.02522 [W/m·K], with an error within 2.9%.