摘要
新型壁面剪应力传感器的出现为河口海岸工程中水下壁面剪应力的准确测量提供了新的方式。热式壁面剪应力传感器受环境温度影响显著,相关传感器的研究与应用需要准确的标定。本文基于宽扁管道内壁面切应力与沿程压力梯度的关系,研发了一种具有温控功能的水下壁面剪应力传感器静态标定装置,可实现不同水温条件下的壁面剪应力输出。该标定装置可提供的最大水温在35℃。最后通过对MEMS柔性热膜式壁面剪应力传感器在不同水温条件下的静态标定实验,确定了不同水温条件下传感器的标定系数,结果表明标定系数B与水温呈线性相关。
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 Band the water temperature is found.
引文
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