Gas Independent Thermal Flow Meter Based on Real-Time Velocity-Independent k and ρcp Measurement

A thermal flow sensor for gases is presented that measures the flow rate independent of the type of the gas by simultaneously measuring and compensating for the thermal conductivity (k) and volumetric heat capacity (ρc p ) of the gas. A suspended wire on a V-groove cavity is used to measure both fluid parameters independent of the flow rate. The output of the thermal flow sensor is automatically corrected for the medium using these measured parameters.