METHOD AND DEVICE FOR LIQUID FLOW RATE MEASUREMENT IN WELL Russian patent published in 2006 - IPC E21B47/10 G01P5/18 

FIELD: oil well survey, particularly to determine liquid flow rate in well.

SUBSTANCE: method involves heating liquid flow in impulse mode; measuring liquid temperature by temperature sensors and comparing signals of two temperature sensors located in common line and spaced from heater; determining liquid flow rate from mathematic relation by the first and the second sensor signals correlation, determination of heat wave delay time between sensor locations, wherein heat wave lengths are maintained so that the heat wave lengths are equal to double distance between the sensors. Pulse relative duration is continuously measured with period 3-5 times exceeding pre-selected heat impulse period. Device for above method realization comprises impulse liquid flow heater, current pulses generator of heater, amplifiers, demultiplexer, analog-digital converter, receiver-transmitter unit, automatic heater current pulse period regulation unit, which regulates heater current period in correspondence with flow rate, one or more temperature sensors installed in line and spaced from heater. Distance between the sensors is not more than double distance between the heater and temperature sensor, which is the nearest to the heater.

EFFECT: increased accuracy of liquid flow rate determination due to elimination of thermal inertia of heater generating heat waves.

6 cl, 4 dwg