基于静电传感器的相关流速测量

Correlative flow velocity measurement based on electrostatic sensor

为了解决传统方法测得的气/固两相流流速具有一定波动性等问题,提出一种新的互相关峰值计算方法——最小二乘法拟合寻峰,利用环状静电传感器与互相关测速原理实现了气/固两相流流速测量.通过静电传感器测得气/固两相流中固相颗粒的随机信号,采用FIR数字滤波处理技术,有效提高了信号的信噪比,在测量过程中实现了真正的非接触式测量.经过反复实验确定了最佳采样频率和采样点数量,与传统方法相比,采用最小二乘法拟合互相关函数寻峰可以使离散的相关峰值点连续,测量误差减小.

In order to solve the velocity fluctuation problem of the gas-solid two-phase flow with the traditional measurement method,a new method to search the peak value of cross correlation function,that is the least square fitting peak-search,was proposed. The flow velocity of gas-solid two-phase flow was measured with ring electrostatic sensor and based on cross-correlation theory. The stochastic signals of the solid phase in gas-solid two-phase flow were obtained by electrostatic sensor and disposed with the FIR digital filter technique. Thus,the signal-to-noise ratio gets effectively increased,and the real non-intrusive measurement is realized. The optimal sampling frequency and sampling point number were determined by the repeated experiments. Compared with the traditional peak-search method,to search peak value with the least square fitting cross correlation function make the discrete correlation peak points become continuous,which will reduce the measurement error.