基于ECT/EST双模信息融合的磨粒图像重建算法

Abrasive Image Reconstruction Algorithm Based on ECT/EST Dual Mode Information Fusion

电容层析成像(ECT)技术因其非侵入、无辐射、可视化、响应快、成本低等优势在两相流测量中获得了广泛应用,但在发动机油路中,因摩擦产生的能量释放使磨粒荷电,对ECT传感器电容值的测量产生扰动,严重影响成像质量。为提高荷电颗粒存在情况下电容层析成像的图像重建质量,提出电容层析成像(ECT)与静电层析成像(EST)双模信息融合成像方法。该方法通过测量荷电颗粒在传感器矩形电极上感应的电荷值,得到荷电磨粒的信息;通过ECT系统得到一组电容值,并利用加权融合的修正方法,对ECT中畸变的电容值进行修正;用修正后的电容值进行图像重建。仿真实验证明:该方法能够弥补单一ECT模态的成像质量不高的不足,减弱荷电颗粒对ECT电容值测量的干扰,明显提高了图像重建质量,降低了成像误差;采用双模态重建图像方法可正确识别环状流、泡状流、核心流等几种典型流型。

Electrical capacitance tomography (ECT) technology has been widely used in two phase flow measurement due to its non invasive,non radiative,visual,fast response,and low cost advantages.In the oil circuit of the engine,the energy released by the friction causes the abrasive particles to be charged,causing disturbance to the measurement of the capacitance value of the ECT sensor,which seriously affects the imaging quality.In order to improve the image reconstruc tion quality of capacitive tomography in the presence of charged particles,two mode information fusion imaging method of the abrasive particles based on ECT and electrostatic tomography (EST) technologies was presented.In this method,by measuring the charge value of charged particles on the rectangular electrode of the sensor,the information of charged abra sive particles was obtained,by correcting the distortion capacitance values of a set of capacitance values obtained by the ECT system with weighted fusion method,the image reconstruction was performed by the corrected capacitance values.Sim ulation experiments show that this method can improve image quality compared with the single ECT mode,and reduce the interference of charged particles on the capacitance measurement by the ECT system,so the image reconstruction quality is significantly improved,and the imaging error is reduced.Several typical flow patterns,such as annular flow,bubbly flow and core flow,can be correctly identified by using two mode information fusion imaging method.