Temperature drift characteristics and compensation study of double-winding thermal mass flow meter

Abstract

Thermal mass flow meters are broadly used in different parts of industry for flow metering objectives. One of the most widely used thermal flow meters is capillary tube type. Aiming at the traditional thermal flow sensor, which has the problems of low flow measurement accuracy and temperature drift, based on the principle of fluid flow and heat transfer, a double-winding distributed thermal flow sensor with constant temperature operation is developed. The thermal flow measurement principle is studied and the sensor temperature field is simulated by COMSOL software. The effect of ambient temperature on the measurement results under different structural parameters and operating parameters is investigated by simulation. The optimal sensor operating parameters are determined, and the sensor temperature adaptability is improved. In addition, under the condition of structural error, the influence of structural error on the measurement is analyzed. Simulation calculations are carried out at different ambient temperatures to obtain the corrected relationship between the measured value and the ambient temperature. Finally, according to the simulation results, the sensor is designed and processed, and tested by the standard flow output device. The temperature correction algorithm is obtained according to the experimental results. And the effectiveness of this temperature correction algorithm is verified under different ambient temperatures and different flow inputs. The experiments show that through this correction algorithm, the test error of the sensor has been significantly reduced in the range of the sensor, and the temperature adaptability of the sensor has been improved.