Method for calculating gas phase flow by utilizing gas holdup of low-yield gas well

Abstract

The invention relates to a method for calculating a gas phase flow by utilizing a gas holdup of a low-yield gas well. The method is characterized in that a hydrodynamic parameter calculation model under a flowing state is especially practically established according to a basic multiphase flow theory model. The method comprises the following steps according to the conditions: S1) collecting the related data of the gas well, including gas holdup, pipe diameter, gas and liquid density, gas and liquid surface tension and local gravitational acceleration; S2) judging gas and liquid two-phase flow type, wherein when the gas holdup is less than 0.8, the flow is static liquid and is a gas upward flowing foamy flow, and when the gas holdup is more than 0.8, the flow is a gas-carrying-water sectional blocking flow; and S3) utilizing a gas flow formula to calculate a gas phase flow QG of a low-yield gas-carrying-water well according to a judging result of the step S2). According to the method provided by the invention, the gas phase flow of the low-yield gas-carrying-water well can be calculated; a new physical model system is established; the calculation result is accurate; and the method can effectively meet the onsite requirement.

Description

technical field [0001] The invention relates to a method for calculating gas phase flow by using gas holdup in a low-yield gas well, and belongs to the technical field of oil and gas field development. Background technique [0002] In the process of oil and gas field development, well logging is required to determine downhole parameters. For gas wells, the traditional method is to use a series of seven parameters (natural gamma ray, magnetic signal, temperature, pressure, density, gas holdup, turbine flow rate) for logging. Among them, the density, gas holdup and turbine flow data are mainly used to determine the phase holdup and flow of each phase of the fluid. For general gas wells, this logging series is effective, and its logging data can accurately determine the gas production profile. However, when the gas well production is low, the trace water produced in the formation will accumulate at the bottom of the well to form a hydrostatic column, and when the liquid level...

AI Technical Summary

Problems solved by technology

When there is water-carrying flow in the gas well, the log curve of the central turbine flowmeter fluctuates greatly. In addition, the turbine flowmeter is seriously affected by the start-up speed in low-production wells

Therefore, under the above circumstances, the rotor speed of the turbine flowmeter does not satisfy the linear relationship with the fluid flow rate, so the logging data of the turbine flowmeter cannot be used to determine the gas flow rate in the wellbore.

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