The water level in refrigerator must be controlled accurately in order to adjust the refrigerator's temperature, namely, a
flow sensor needs to be designed to precisely measure the water flow into the flume according to the structure of hydrovalve.
So the mechanical model of the turbine impeller's vane was first done through the analysis of the vane's beard
driving and dragging force torques, and the instrument constant of the flow sensor was deducted, the dynamic
measurement characteristics of the flow sensor was then analyzed to analyze the measurement precision of the flow
sensor. The structure of flow sensor has been designed according to the results of theoretical analysis, and the flow field
simulation of the turbine flowmeter has been done using the software of FLUENT. The theoretical and experimental
results show that the mechanical model of the turbine flowmeter is reasonable and the mathematical expression of the
ideal instrument constant can be adopted as the design reference of the flow sensor.