GAS FLOW RATE MEASUREMENT

摘要

Measurement of gas flow in a nearly-horizontal ascending borehole utilising a pair of correlated spaced sensors (49n, 49f) that can detect "directly" the difference between gas (11) and liquid (13: oil and/or water), which sensor pair (49) is carried on a logging tool (41) positioned within the borehole (20) itself such that the individual sensors (49) are disposed so as to be actually in the path of any gas bubbles (12) likely to be in the fluid. The correlated output of the sensor pair (49) allows a determination of the gas flow velocity, and if at the same time measurements are taken that provide an indication of the hold-up of the gas bubbles there may by calculation be determined the flow rate both of the gas and of the fluid.