Method for predicting wellbore pressure and temperature field simulation as well as hydrate through deep-water test

Abstract

The invention relates to a method for predicting wellbore pressure and temperature field simulation as well as hydrate through deep-water test. The method comprises the following steps: preparing parameters; initializing a wellbore temperature field and pressure field; solving formation flow and bottom-hole pressure distribution information by using a seepage flow mathematical model for gas reservoir; inputting the formation flow and bottom-hole pressure distribution information into a wellbore flow model for iteration to solve a wellbore pressure profile and determine whether the wellbore pressure is converged or not; calculating thermophysical parameters, and calculating a total heat transfer coefficient of a formation section and a seawater section; substituting the wellbore pressure and the total heat transfer coefficient into a wellbore temperature field model to calculate the wellbore temperature profile of each node; determining whether the wellbore temperature profile is converged; determining whether tn is less than (tn+1) or not, if yes, outputting a well temperature-well depth curve and a hydrate generation temperature-well depth curve corresponding to the wellbore pressure, and determining whether a hydrate is generated according to the curves; or else, returning to predict the conditions of wellbore pressure and temperature field simulation as well as hydrate. According to the invention, the method can be widely used in the oil exploration process.

Description

technical field [0001] The present invention relates to a deep water test wellbore pressure, temperature field and hydrate prediction method, in particular to a deep water test wellbore pressure, temperature field simulation and method under the influence of seawater temperature under the steady state heat transfer and unsteady state heat transfer of the wellbore. Hydrate prediction method. Background technique [0002] At present, the form of my country's energy development is becoming more and more serious, and the deep water area of ​​the ocean has gradually become the focus of exploration and development. However, for deep-water oil and gas fields, they generally have the characteristics of deep burial, high temperature, high pressure, and good permeability of the reservoir. That is, under normal circumstances, production wells in deep-sea oil and gas fields are often high-yield wells. Gas combined with the cooling effect of seawater and multi-stage throttling for high ...

AI Technical Summary

Problems solved by technology

However, the simulation prediction of wellbore temperature field and pressure profile by PIPESIM software has the following disadvantages: 1. The prediction of wellbore pressure profile is based on the assumption that the wellbore temperature profile changes linearly. The result is very biased

2. The unsteady heat transfer between the wellbore and the formation is not considered in the short-term process of oil testing

3. Does not consider sea temperature changes

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