Sensitivity formulation for electromagnetic flow tomography considering the conductivity distribution

The electromagnetic flow tomography (EMFT) technique aims to map the flow velocity profile by interrogating the electromotive force (emf) from the boundary of flow that travels in an electromagnetic field. In principle, the induced potential depends on not only the flow velocity but also the conductivity distribution. In the case of an electromagnetic flowmeter (EMF), the conductivity of fluid is assumed uniform or at least axisymmetric. However, in the case of multi-phase flows, the conductivity distribution is non-uniform and will affect the induced potential distributions. Therefore, applying the EMF model in the non-uniform/asymmetric conductivity distributions will inevitably introduce errors in calculating the velocity profile. In this paper, the forward problem of EMFT has been investigated by taking the conductivity distribution into account. Numerical simulations showed that the proposed non-uniform model has the unique capability in dealing with the fluid of asymmetric and non-uniform conductivity distributions.