Measurement of velocity profiles in transient single and multiphase flows using inductive flow tomography

Velocity profile reconstructions from the EMFM device, both in single phase and multiphase flow, show that when the valve is suddenly opened or closed, the flow downstream of the valve oscillates - with the velocity profile successively changing between a very peaky profile with a much higher than expected velocity at the pipe centre to a velocity profile where the velocity at the pipe centre is much lower than expected. This oscillation occurs until steady state conditions are again reached. It is believed that these novel measurements of transient velocity profiles demonstrate hitherto unseen flow behaviour which may explain some of the damaging effects associated with the phenomenon of 'water hammer'.