A Dual Mode Ultrasound and Electrical Capacitance Process Tomography Sensor

The tomographic imaging of process parameters in industrial applications can be based on different sensing modalities, e.g. ultrasonic waves and electrical capacitance, all of which are sensitive to specific properties of the materials to be imaged. They have shown to be useful tools for process monitoring in different industries. However, the achievable image quality and resolution are generally limited in practice due to the ill-posedness of the inverse problem and limited available data. To further improve the results, the fusion of ultrasound transmission tomography (UTT) and electrical capacitance tomography (ECT) for monitoring two-phase flows is proposed in this paper. The two methods offer complementary properties, making them well suited for data fusion. The ultrasound image is used as a priori information for the finite element method-based capacitance reconstruction algorithm. A tentative dual-mode sensor and static measurements of gas-solid two-phase material distributions are presented. The results indicate that a significant improvement in image quality can be achieved with the proposed sequential tomography sensor fusion