초록 ▼

A method and apparatus for a total and individual flow measurement of a multi-phase gas/liquid medium with wide range of gas to liquid ratio provides high accuracy and tolerance of hydraulic and mechanical disturbances. The flow meter sensing element includes a hollow pendulum having two oscillators

A method and apparatus for a total and individual flow measurement of a multi-phase gas/liquid medium with wide range of gas to liquid ratio provides high accuracy and tolerance of hydraulic and mechanical disturbances. The flow meter sensing element includes a hollow pendulum having two oscillators symmetrically positioned about its first portion and second portion. Non-fading oscillations of the pendulum provided by these oscillators are maintained constant at resonant frequency by the control unit by adjusting the amount of energy supplied to both oscillators regardless of the disturbances caused by Coriolis forces from the flowing medium. The total flow is computed based on the difference in the electrical energy supplied to both oscillators. Detection of the "zero drift" is based on the sum of electrical currents supplied to both oscillators. In one embodiment, the shape of the pendulum is straight. In another embodiments, a plurality of parallel pendulums are assembled together and in one plane to increase the flow capacity of the flow meter. In yet another embodiment, a pair of pendulums are forming a "tuning fork". The apparatus allows for accurate measurements of the total and individual flow rates of a multi-component medium such as gas-oil-water mixtures coming out of an oil well.

대표청구항 ▼

[ What I claim is:] [1.] An apparatus for a total and individual flow measurement of a multi-phase gas/liquid medium, said apparatus comprising:a hollow pendulum having an inlet, a midpoint, and an outlet, the inlet and the outlet being fixed in place, said pendulum having a first portion between th

[ What I claim is:] [1.] An apparatus for a total and individual flow measurement of a multi-phase gas/liquid medium, said apparatus comprising:a hollow pendulum having an inlet, a midpoint, and an outlet, the inlet and the outlet being fixed in place, said pendulum having a first portion between the inlet and the midpoint and a second portion between the midpoint and the outlet, said portions being symmetrical about a line forming an axis of symmetry of said pendulum, said line going through said midpoint and a midway point between the inlet and the outlet of said pendulum;a first pair of electromagnets and a second pair of electromagnets for causing non-fading oscillations of said pendulum, said medium flowing through said pendulum from the inlet to the outlet causing Coriolis forces to disturb said oscillations, said first pair of electromagnets positioned about the first portion of said pendulum, said second pair of electromagnets respectively positioned about the second portion of said pendulum, said first and second pairs of electromagnets positioned symmetrically about the axis of symmetry of said pendulum, said first pair of electromagnets having a first electromagnet and a second electromagnet positioned opposite said first electromagnet about said pendulum and forming a closed electromechanical loop with said first portion, said second pair of electromagnets having respectively a third electromagnet and a fourth electromagnet positioned opposite said third electromagnet about said pendulum and forming a closed electromechanical loop with said second portion; anda control unit for said first and second pairs of electromagnets, said unit individually adjusting electrical currents supplied to said first and second pairs of electromagnets to compensate for oscillation disturbances caused by said Coriolis forces, said unit computing the total flow of the medium through said pendulum and the flow rates of all components of the medium based on the difference in electrical currents supplied to said first and second pairs of electromagnets and the change in frequency of said pendulum oscillations caused by the flowing medium.