DOWNHOLE TOOL FOR DETERMINING FLOW VELOCITY Russian patent published in 2017 - IPC G01F1/66 

FIELD: mining; measurement equipment.

SUBSTANCE: present invention relates to a downhole tool for determining flow velocity of fluid inside a borehole or borehole casing. Downhole tool comprises a tool housing extending along a longitudinal axis and having a circumference which is perpendicular to longitudinal axis, said tool housing being adapted to be lowered inside borehole or borehole casing, longitudinal transducer transmitting a probing signal substantially longitudinally from an end part of tool housing into a fluid flowing in said borehole or borehole casing, so that transmitted probing signal is exposed to reflective entrained surfaces in flowing fluid, and longitudinal transducer receiving a reflected signal reflected substantially from reflective entrained surfaces in fluid flowing in said well along a longitudinal direction towards end part of tool housing, and whereby a flow velocity of fluid may be extracted from consecutive received signals, a plurality of electrodes spaced apart around longitudinal axis in periphery of tool so that fluid flows between electrodes and a borehole wall or borehole casing wall, and a measuring means for measuring capacitance between two electrodes in all combinations giving n⋅(n-1)/2 capacitance measurements for n electrodes, wherein downhole tool has a space between every two electrodes, which space is substantially filled up with a non-conductive means in order to determine properties of fluid.

EFFECT: creation of improved downhole tool, configured to determine flow rates of fluid media with complex flow modes and in mixed fluid media inside borehole or borehole casing.

17 cl, 8 dwg