On-line EM wave sensor for water fraction metering

摘要

The University of Liverpool has developed, in conjunction with Solartron ISA, an on-line water fraction monitoring system. This sensor transmits low power (<20mW) radio frequencies (RF) in the range of 100MHz-1GHz and detects resonant frequencies using a Marconi 6200 test set. The multiple resonances from each captured RF spectrum are analysed to determine the water fraction in the pipeline. The sensor is non-invasive, and relies on the relatively high dielectric constant of the water phase. This is a volumetric sensor, it is not designed to detect slippage. An industrial version of the sensor for a 102mm (4 inch) diameter pipe has been constructed, based upon a laboratory prototype, and trials have been conducted on the test loop at the National Engineering Laboratories (NEL) in the UK with dispersed and annular flow regimes. Laboratory and NEL results will be presented.