摘要
为实现流体壁面剪应力在线测量,设计了一种基于柔性热膜传感器的流体壁面剪应力测量系统。通过分析柔性热膜传感器作用机理,研发了基于LTZ1000电压基准的高精度恒流驱动电路,开发了基于DSP2812,AD7609的18位真差分同步高速数据采集模块,并通过温度补偿方法对传感器输出信号进行了环境温漂修正。系统性能测试表明:当流场温度在10～30℃范围变化时,剪应力测量分辨率在0～10 Pa范围内优于0.2 Pa,流体温度变化引起的系统输出信号偏差为0.6%/℃,满足实际流体壁面剪应力测量要求。
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 -30 ℃ ,at range 0 -10Pa,and an output signal deviation of system is 0.6 %/℃ ,which meet wall shear stress measurement requirement of actual fluid.
出处
《传感器与微系统》
CSCD
北大核心
2013年第7期101-105,共5页
Transducer and Microsystem Technologies
基金
国家自然科学基金资助项目(51105317)
关键词
壁面剪应力
柔性热膜
测量系统
恒流驱动
温度补偿
wall shear stress
flexible hot film
measurement system
constant current drive
temperature compensation
