Optical fibre sensors for imaging concentration profile

The work presented here aims to investigate the use of optical fibre sensors arranged in multiple projections around a vertical transparent flow pipe for measurement of gas bubbles being conveyed by water. Light is injected through the measurement section and detected by fibre optic sensors, which transfer the light energy to photodiodes. These provide an electrical output, which is amplified, signal processed and fed to a PC for further analysis. The sensors measure the changes in absorption or attenuation of the conveyed material and information obtained in this way allows an image of the cross-section of the flow to be reconstructed by a computer.