Research on the calibration device with temperature control for underwater wall shear stress sensor

The appearance of new wall shear stress sensors provides new methods for measuring the underwater bed shear stress in estuarine and coastal engineering. The thermal wall shear stress sensor is affected by the ambient temperature significantly. The relevant research and application of these sensors are inseparable from the accurate calibration. Based on the relationship between the wall shear stress and the pressure gradient along the duct with high aspect ratio, a static calibration device for underwater wall shear stress sensor with temperature control is developed. This device can produce wall shear stress for calibration at different water temperature. The calibration device can provide a maximum water temperature of 35℃. A static calibration experiment of the MEMS flexible hot-film wall shear stress sensor is conducted using the device, and the calibration coefficients under different water temperature conditions are determined. The linear relation between the calibration coefficient B and the water temperature is found.