Unlock instant, AI-driven research and patent intelligence for your innovation.

Three-dimensional numerical model design for sand production of oil well

A three-dimensional numerical and model design technology, applied in the direction of calculation, 3D modeling, image data processing, etc., can solve the problems of difficult determination of fluid boundary conditions, complex interactions, and inability to accurately explain the occurrence and development process of sand production. Feasibility and stability, effect to ensure effectiveness

Inactive Publication Date: 2013-05-01
CHONGQING UNIV
View PDF3 Cites 4 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0003] For the actual reservoir production, the fluid movement during the perforation process and the interaction between the formation force and the fluid are complex, and the mechanical properties of the sandstone during the sand production process of the oil well are also complex. Conventional laboratory test methods and equivalent continuum analysis methods cannot reflect For the mesoscopic characteristics of sandstone particles, although some scholars have started mesomechanical analysis based on the theory of soil mechanics, the two-dimensional discrete element model based on Darcy seepage cannot accurately reflect the occurrence and development of sand production in oil wells
Especially in conventional water injection production, considering that the fluid movement in the perforation process is mainly in the radial direction, if the fluid movement is still studied in the Cartesian coordinate system, it is difficult to determine the fluid boundary conditions in the numerical simulation and cannot accurately describe the perforation. The porosity change and fluid-solid coupling effect in the pore process cannot accurately explain the occurrence and development process of sand production

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Three-dimensional numerical model design for sand production of oil well
  • Three-dimensional numerical model design for sand production of oil well
  • Three-dimensional numerical model design for sand production of oil well

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0043] This embodiment discloses a specific three-dimensional numerical simulation method for oil well sand production, which mainly includes the following steps, namely:

[0044] The first step: read in the data of the actual oil well, and establish a three-dimensional numerical model of the oil well in the cylindrical coordinate system. Among them, the most important thing is to establish the three-dimensional numerical model of the perforation in the cylindrical coordinate system according to the specific size and position of the perforation.

[0045] The perforation three-dimensional numerical model has an inner hole radius, an outer radius of the perforation model, and an elastic-plastic boundary. The actual perforation is distributed in the sandstone around the oil well, including the through inner hole and the sandstone around the inner hole. The sandstone near the inner hole is the plastic area, and the periphery of the plastic area is the elastic area. see figure 1...

Embodiment 2

[0061] In this embodiment, according to the method disclosed in Embodiment 1, fluid-solid coupling analysis is performed.

[0062] With the fluid unit N in embodiment 1 i For example, get t=t 1 porosity and the fluid pressure gradient and drag forces acting on the particles. Due to the movement of particles under force, the position of particles is redistributed, and the porosity of the fluid unit changes. The change of the porosity in turn causes the change of the drag force and the fluid pressure gradient, thereby causing the change of the micro-mechanical effect of the particles and the macro-mechanical properties of the model. As an implementation, the time increment step Δt, obtain t=t 1 Porosity at +Δt and fluid pressure gradient and drag forces acting on the particles. According to the calculated drag coefficient and fluid pressure coefficient The fluid-structure interaction force acting on the particles is obtained:

[0063] Forces acting on sandstone grains ...

Embodiment 3

[0067] In this embodiment, the specific reservoir sandstone is selected, and the ratio of the largest particle to the minimum particle radius of the sandstone, the density of the sandstone particle, the normal stiffness and tangential stiffness of the parallel bond, the friction coefficient of the particle, the normal stiffness and the tangential stiffness of the particle are set. Tangential stiffness, normal strength and tangential strength of parallel bonding, minimum particle radius and bonding radius ratio of bonding degree, average diameter of particles along radial direction average particle velocity and the average velocity u of the fluid element f，r . The above parameters are obtained according to the actual oil well perforation test, and the parallel bond stiffness and particle stiffness are determined according to engineering experience and tests. According to the method disclosed in Example 1, the porosity of each fluid unit, the drag force and pressure gradient...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

PropertyMeasurementUnit
Particle sizeaaaaaaaaaa
Login to View More

Abstract

The invention aims at providing a model design method which takes perforation test characteristic into account and reflects macroscopic and microscopic mechanical properties of sandstone in a perforation test. The technical scheme for implementing the purpose of the invention is as follows: the three-dimensional numerical model design for sand production of the oil well comprises the following steps of: (1) reading-in the geometric dimension of an actual oil well and establishing a three-dimensional numerical perforation model under a cylindrical coordinate system; (2) dividing the three-dimensional numerical perforation model into a plurality of units according to the actual situation of the perforation test process; (3) calculating the porosity of each unit according to the rock particle distribution of the three-dimensional numerical perforation model; (4) calculating the fluid pressure gradient force and the dragging force according to the porosity, wherein the fluid pressure gradient force and the dragging force cause redistribution of rock particles in the three-dimensional numerical perforation model; and (5) repeating the step 3 and the step 4 till a computing process is converged.

Description

technical field [0001] The invention relates to the field of petroleum engineering, in particular to the design of a three-dimensional numerical model for oil well sand production. Background technique [0002] According to statistics from the National Bureau of Statistics, the dependence on crude oil imports soared from 24.8% in 2000 to 57.16% in 2012, exceeding the safety warning line of 50%. One of the bottlenecks in the sustainable development of oil exploitation is the problem of sand production in oil wells. Sand production not only brings a lot of trouble to the oil recovery process, but also affects the oil recovery rate and oil and gas recovery rate of the reservoir. In severe cases, it will cause the well wall to collapse and the casing to be damaged. Even oil wells are scrapped. Therefore, the problem of reservoir sand production has brought a huge challenge to oil production. Sand production prediction and prevention are research hotspots and difficulties in the...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
IPC IPC(8): G06T17/00
Inventor 刘先珊许明
Owner CHONGQING UNIV