Bohrlochmessgerät mit Impedanz-Kreuzkorrelation.

摘要

The logging tool comprises a gas void fraction measurement section (37) consisting of a first set (37) of eight longitudinal electrodes (38) extending parallel to the longitudinal axis of the tool and positioned and regularly spaced around said longitudinal axis, a sleeve (40) made of dielectric material and located in contact and around the electrodes for obtaining an electric field pattern distributed essentially radially between the electrodes and the wall (12) of the borehole facing the electrodes (38), a centralizer (32) for substantially centralizing the tool in the borehole, and a circuit means (69-115) for measuring sequentially the capacitance between two adjacent electrodes for each pair of electrodes, said capacitance being characteristic of the gas void fraction of the fluid flowing in the wellbore. The logging tool comprises in addition a cross correlation gas velocity measurement section (28) which includes a second (48) and a third (50) set of electrodes.