Patent ID: 6046587
Filing Date: 2000-04-04
Classification: E21B,G01F,G01N,G01R,G01V,Y02A

Abstract:
A flowmeter for a fluid flowing through a flow channel, comprising:a pre-polarizer for polarizing said fluid;a NMR sensor for providing NMR output data from the polarized fluid;an NMR detector for powering said NMR sensor at the NMR frequency and for amplifying and detecting an NMR signal induced in said sensor from the polarized and energized liquid flow; anda processor programmed to calculate flow velocity by obtaining a first NMR signal emitted by completely polarized and energized fluid in said NMR sensor, obtaining a second signal emitted by said fluid after a delay time less than the time required for said fluid to flow out of said NMR sensor, and comparing the amplitudes of the said first NMR signal and said second NMR signal;wherein said processor is further programmed to calculate a gas fraction of said fluid from the NMR signal amplitude and from temperature and pressure measurements.