Underground optical fiber flow sensor in oil field

Abstract

The invention relates to a petroleum logging instrument, and particularly to an underground optical fiber flow sensor in an oil field. A light source module of the sensor is connected to a polarization controller; the polarization controller is connected to an optical fiber coupler; the optical fiber coupler is respectively connected to a phase modulator, a Faraday rotating head II and a photoelectric detector; the phase modulator, a Faraday rotating head I and an optical fiber pressure sensing head I are connected sequentially; the Faraday rotating head II is connected to an optical fiber pressure sensing head II; and the photoelectric detector, an amplification circuit and an A / D (Analogue / Digital) converter and an embedded computer are connected sequentially. The underground optical fiber flow sensor in the oil field realizes absence of direct function of a fluid and optical waves, can realizes wholly sealed packaging, satisfies fluid flow measurement in a high-temperature and high-pressure severe environment, has high measurement sensitivity and high measurement precision, and overcomes the disadvantage that the conventional optical fiber sensor cannot be satisfied with the environment requirements of the underground flow measurement of petroleum.

Description

Technical field: [0001] The invention relates to a petroleum logging instrument, in particular to an oil field downhole optical fiber flow sensor. Background technique: [0002] At present, the optical fiber sensors used for liquid flow measurement include turbine optical fiber flow sensors, vortex optical fiber flow sensors, Doppler optical fiber speed sensors, and fiber grating flow sensors. Turbine optical fiber flow sensor has a simple structure and simple signal processing method, but the transmitted light in the optical fiber is projected onto the turbine through the spatial light path, and then the reflected light is received, and the flow measurement is realized by counting. The low flow turbine cannot be started, and the oil The strong absorption of light causes problems such as very weak reflected light, so it cannot meet the requirements of the oil well test environment. The vortex optical fiber flow sensor utilizes the fluid to pass through an obstacle to form two ed...

AI Technical Summary

Problems solved by technology

It overcomes the shortcomings that the existing optical fiber sensors cannot meet the environmental requirements of oil well flow measurement

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