To get the most from applying electrical tomography sensing techniques to the understanding of multiphase flows it is necessary to use dual modality sensors.
The ERT sensing capability can characterise the water continuous phase whilst ECT sensing capability characterises the oil continuous phase. Whilst often turbulent flows are one system or the other, it is necessary to have both capabilities in place in order to measure both flow regimes, particularly if phase inversion occurs, switching between the necessary modalities.
ITS has also developed software to fuse dual modality data sets, where ERT is used to define regions which are aqueous, and ECT is used to define the remaining regions as either oil or gas.
In addition, it is necessary to have both modalities in place for the appropriate measurement of stratified flows.
ITS is the only organisation in the world that has developed ERT / ECT dual modality sensors for the study of multiphase flows and has provided these to research groups in several flow research facilities around the world.
As ERT sensors are inside the pipe (adjacent to the flow) and ECT sensors are separated from the flowing materials by a liner, it is possible to co-locate the sensing planes. However for greater flexibility (and ease of manufacture) generally the sensing planes are independent of each other.
Sensors have been designed to operate in challenging environments and designed to be ATEX rated as well as capable of working under high pressure (120 bar) and extreme temperatures (from -30℃ to 120℃).