A wall shear stress measurement system based on flexible hot film sensor is developed to realize wall shear stress on-line measurement.Through analysis on working principle of flexible hot film sensor

a high precision constant current drive circuit based on LTZ1000 voltage standard is developed

and a 18 bit real differential simultaneous data acquisition module which based on DSP2812

&

AD7609 are developed

temperature compensation method is used to revise environmental temperature drift of sensor output signal.System character test indicates that the shear stress measurement system achieves a resolution prior to 0.2 Pa at fluid temperature 10

3

0 ℃

at range 0

1

0Pa

and an output signal deviation of system is 0.6 %/℃

which meet wall shear

stress measurement requirement of actual fluid.