Design of microcalorimetric mass flowmeter based on constant power

In this paper, a design method of a thermal mass flowmeter based on constant power is proposed. The purpose is to measure the flow of a small amount of fluid. The principle is to arrange two temperature sensors in the pipeline to heat the speed-measuring temperature sensor. The principle calculates the flow. The polynomial least squares method is used to establish the mathematical model between the fluid flow and the sensor output voltage, and the output signal is processed by the single chip microcomputer. The experimental results show that the relative error of the designed thermal mass flowmeter is within 1.5%. The flowmeter has the advantages of large measurement range, high measurement accuracy and good repeatability.