ECT技术对成像的影响——用低介电参数物质标定

电容层析成像技术是20世纪80年代发展起来的一种多相流参数检测技术.它是利用多相介质具有不同的介电常数,通过电容传感器测量获得介电常数分布而获得介质分布的图像.可以用来测量多相流尤其是气固两相流的流动分布,该方法具有快速,不干扰流场、结构简单、无辐射、成本低的特点.但该方法对于测量低介电参数材料固体流动或稀相流动比较困难.提出使用更低介电参数的物质进行标定,可以提高ECT的成像效果.应用Ansoft仿真软件计算了方形管道内存在圆棒时的成像效果,比较了用高低不同介电参数物质进行标定的成像效果,通过方形传感器验证了该结论的正确性.

The Influence of Image Quality of Calibrating --With Low Permittivity Material in ECT

Electrical capacitance tomography is a measure technology for measuring flow styles in multi-phase flow and concentration profile in gas/solid flow from the 1980s. By using multiphase medium with different permittivity, the image of medium distribution could be obtained through measuring the obtained permittivity by capacitance sensor. It has the characteristics of fast image, non-intrusion, non-radiation, low cost. It is difficult to measure low permittivity solids concentration especially dilute concentration using ECT. Using low permittivity material to calibrate can improve the quality of image. The image effect is calculated by using Ansoft emulation software. The image effects calibrated by low or high permittivity materials are compared. This conclusion is validated through simulation and experiment.