On-line monitoring of nonaxisymmetric flow profile with a multielectrode inductance flowmeter

A modified filtered backprojection (FBP) algorithm based on a revised S-L filter functions is developed to monitor the velocity profile of nonaxisymmetric flow inside a circular pipe with a multielectrode inductance flowmeter. This algorithm is simpler than the singular value decomposition (SVD) and pseudoinverse-based algorithms and fast enough to be used in on-line monitoring of flow profile. To further improve its realtime performance, a simplified algorithm is also proposed. Three kinds of nonaxisymmetric flow profiles, i.e., profiles with a single peak, with double peaks and with one peak and one reflux are simulated to evaluate the performance of the proposed algorithms. The projection data are obtained by solving the governing electric field equation. With these data the velocity profile of the pipe flow can be reconstructed using the new algorithms. The reconstructed profiles have been compared with those obtained by using simple backprojection methods. Results obtained demonstrate that the algorithms can be used to monitor the velocity profile of nonaxisymmetric pipe flows.