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Methods and apparatuses for detecting radial flows of conductive fluid are provided. In an embodiment of the present invention, shields are used to prevent or reduce circulating electrical currents from causing a voltage difference that would adversely affect the measured voltage difference between

Methods and apparatuses for detecting radial flows of conductive fluid are provided. In an embodiment of the present invention, shields are used to prevent or reduce circulating electrical currents from causing a voltage difference that would adversely affect the measured voltage difference between two adjacent electrodes. The shields may be a conduit through which conductive fluid may flow. Groups of sensors, e.g., two or more, may be placed within the shield. The shields may have any cross-section shape. Generally, once the circulating electrical current flow between the electrode pairs is substantially reduced or eliminated, only the voltage difference from the localized induced electric field remains. This way, a true induced voltage may be measured, and thus an accurate value for the fluid velocity may be determined.

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1. A method of measuring fluid flow in a borehole having an interior wall, the method comprising: traversing the borehole with a tool body having a sensor attached thereto, wherein shields are disposed along the sensor, and wherein voltage sensing electrodes are disposed on interior surfaces of the

1. A method of measuring fluid flow in a borehole having an interior wall, the method comprising: traversing the borehole with a tool body having a sensor attached thereto, wherein shields are disposed along the sensor, and wherein voltage sensing electrodes are disposed on interior surfaces of the shields; anddetecting a radial flow of conductive fluid entering or leaving the borehole interior wall with the voltage sensing electrodes. 2. The method of claim 1, wherein the shields are interconnected. 3. The method of claim 1, wherein the shields comprise a conduit through which fluid may flow. 4. The method of claim 1, wherein the voltage sensing electrodes comprise a point electrode. 5. The method of claim 1, wherein the voltage sensing electrodes comprise a longitudinal electrode. 6. The method of claim 1, wherein the voltage sensing electrodes substantially cover opposing sides of the shields. 7. The method of claim 1, wherein the sensor is a sensor loop. 8. A method of measuring fluid flow in a casing having an interior wall, the method comprising: traversing the casing with a tool body having a plurality of electrodes and a plurality of shields, each shield comprising a conduit through which fluid may flow and having two or more electrodes therein;generating a magnetic field substantially perpendicular to an imaginary line between adjacent electrodes; andmeasuring, with the electrodes, an induced voltage indicative of a substantially radial flow of conductive fluid entering or leaving the casing interior wall. 9. The method according to claim 8, wherein the magnetic field is an alternating magnetic field. 10. The method according to claim 8, further comprising maintaining the plurality of electrodes near the interior wall of the casing. 11. The method according to claim 8, wherein the plurality of electrodes are positioned on a sensor body, and the method further comprises adjusting the sensor body such that the sensor body fits within the casing. 12. The method according to claim 11, wherein the adjusting includes radially moving the sensor body outward from and inward toward a central axis of the casing. 13. The method according to claim 8, wherein the generating a magnetic field comprises generating an alternating magnetic field. 14. A method of measuring radial fluid flow in a borehole having an interior wall, the method comprising: traversing the borehole with a tool body having a sensing device;positioning pairs of voltage sensing electrodes that are disposed along the sensing device adjacent to the borehole interior wall;isolating each of the pairs of voltage sensing electrodes with shields interposed between each of the pairs of voltage sensing electrodes; anddetecting a radial flow of conductive fluid entering or leaving the borehole interior wall. 15. The method of claim 14, wherein the shields are interconnected. 16. The method of claim 14, wherein the shields comprise a conduit through which fluid may flow. 17. The method of claim 14, wherein each voltage sensing electrode comprises a point electrode. 18. The method of claim 14, wherein each voltage sensing electrode comprises a longitudinal electrode. 19. The method of claim 14, wherein each pair of voltage sensing electrodes substantially covers opposing interior sides of their respective shield. 20. The method of claim 14, wherein the isolating comprises isolating each of the pairs of voltage sensing electrodes from ambient electrical current flow between the pairs of voltage sensing electrodes.