Search

CN-121993175-A - Physical simulation device and method for three-phase seepage-free flow coupling of fracture-cavity oil reservoir

CN121993175ACN 121993175 ACN121993175 ACN 121993175ACN-121993175-A

Abstract

The invention provides a physical simulation device and a physical simulation method for three-phase seepage-free flow coupling of a fracture-cavity oil reservoir, wherein the physical simulation device comprises a fluid supply unit, a visual physical model, an observation unit, a control unit and a separation metering unit; the fluid supply unit is connected with an inlet end of the visual physical model, the separation metering unit is connected with an outlet end of the visual physical model, the visual physical model comprises a first flat plate and a second flat plate, a hollow layer is formed between the first flat plate and the second flat plate, and a fracture-cavity structure is etched on the first flat plate. The simulation device and the simulation method can realize the oil-gas-water three-phase seepage-free flow coupling simulation of the fracture-cavity oil reservoir, realize the real-time monitoring of the change of the flow rule through the visual model, acquire the flow change rule and the fluid flow characteristic, and realize the conversion of the oil-gas-water three-phase seepage-free flow coupling problem from numerical simulation to physical experiment simulation.

Inventors

  • WANG QI
  • ZHANG JING
  • WANG ZIZHENG

Assignees

  • 中国石油天然气股份有限公司

Dates

Publication Date
20260508
Application Date
20241108

Claims (10)

  1. 1. A physical simulation device for fracture-cavity oil reservoir oil-gas-water three-phase seepage-free flow coupling, the physical simulation device comprising: The system comprises a fluid supply unit, a visual physical model, a control unit, a separation metering unit and an observation unit; The fluid supply unit is connected with the inlet end of the visual physical model; the separation metering unit is connected with the outlet end of the visual physical model; the visual physical model unit comprises a first flat plate and a second flat plate, a hollow layer is formed between the first flat plate and the second flat plate, and a fracture-hole structure is etched on the first flat plate.
  2. 2. The physical simulation device according to claim 1, wherein the fluid supply unit comprises a gas phase supply device, an oil phase supply device, an aqueous phase supply device, a hydrodynamic device, a gas phase intermediate container, an oil phase intermediate container, and an aqueous phase intermediate container; preferably, displacement sensors are arranged in the gas phase intermediate container, the oil phase intermediate container and the water phase intermediate container.
  3. 3. The physical simulation device according to claim 2, wherein in the fluid supply unit, the gas phase supply device, the oil phase supply device and the water phase supply device are connected to a gas phase intermediate container, an oil phase intermediate container and a water phase intermediate container, respectively, which are connected in parallel to a visual physical model.
  4. 4. A physical simulation device according to any one of claims 1-3, wherein the material of the visual physical model is plexiglass.
  5. 5. The physical simulation device according to any one of claims 1 to 4, wherein the fracture-cavity structure is obtained by laser etching according to a CAD image of the actual form of the fracture-cavity reservoir; preferably, the hole-gap structure is filled with a porous medium mixed by glass beads and epoxy resin; preferably, the porous medium has a packing volume fraction of 0.1-100%; Preferably, the mass ratio of glass beads to epoxy resin in the porous medium is (1-5): 100.
  6. 6. The physical simulation device according to any one of claims 1 to 5, wherein the control unit comprises a six-way valve and a three-way valve; Preferably, the six-way valve is arranged on an inlet pipeline of the visual physical model; preferably, the three-way valve is provided on a gas phase line in the fluid supply unit.
  7. 7. The physical simulation device according to any one of claims 1 to 6, further comprising a pressure sensor provided on the control unit.
  8. 8. The physical simulation device of any of claims 1-7, wherein the observation unit comprises a light source, an image recording device, and a fluid velocity measuring device.
  9. 9. A physical simulation method of fracture-cavity oil reservoir oil-gas-water three-phase seepage-free flow coupling, characterized in that the physical simulation method uses the physical simulation device of any one of claims 1-8, and the physical simulation method comprises the following steps: (1) Starting a fluid supply unit to fill a pipeline of the physical simulation device with fluid and remove air; (2) Weighing the dry weight of the visual physical model, then saturating the visual physical model with simulated oil, calculating the volume of saturated oil, and recording the pressure value; (3) According to the displacement working condition of the experimental scheme, injecting gas and/or water into a visual physical model through a control unit and a fluid supply unit, adjusting fluid parameters to the displacement working condition, enabling the device to stably operate, completing the displacement process, recording pressure values and oil, gas and water three-phase flow data in the displacement process, recording a flow image, and measuring the flow speed change of a coupling interface; (4) And acquiring and analyzing data of the three-phase interface condition in the flowing image, and analyzing the seepage and free flow characteristics of the fluid in the fracture-cavity medium and the seepage free flow interface coupling rule.
  10. 10. The physical simulation method according to claim 9, wherein in the displacement working condition, the pressure is 0.1-0.2MPa; Preferably, in the displacement working condition, the fluid injection speed is 2-10mL/min.

Description

Physical simulation device and method for three-phase seepage-free flow coupling of fracture-cavity oil reservoir Technical Field The invention belongs to the technical field of oil reservoir development, relates to a physical simulation device of a fracture-cavity oil reservoir, and particularly relates to a physical simulation device and method for oil-gas-water three-phase seepage-free flow coupling of the fracture-cavity oil reservoir. Background The carbonate fracture-cavity type oil reservoir is an oil reservoir type with special geological characteristics, has extremely strong heterogeneity, is composed of various structures such as cracks, karst cavities and pores, has the remarkable characteristics of various fracture-cavity forms and complex communication relations, has extremely complex fluid flow rules, increases great difficulty for engineering development and scientific research of the fracture-cavity type oil reservoir, and particularly has the problem that numerical simulation of the fracture-cavity oil reservoir is difficult to accurately simulate an actual reservoir due to uncertainty of reservoir parameters. For fracture-cavity oil reservoirs of fracture-cavity structures, physical experiments are the most effective method for researching the oil reservoirs. The physical experimental research of the fracture-cavity oil reservoir development is from none to deep from exploration attempts to innovation, the research content is from simple to complex, the oil-water two-phase flow in single fracture and single cavity is firstly simple, the two-dimensional and three-dimensional simple fracture-cavity structure combination is achieved, the multi-fracture-cavity arranged fracture-cavity network is achieved, the complex fracture-cavity distribution basically conforming to the actual reservoir characteristics is finally developed, the experimental model manufacturing method is updated and iterated continuously, and the development stages of marble arrangement models, organic glass splicing models, carbonate rock plate models, full-diameter corrosion rock core models, organic glass laser etching models, 3D printing models and the like are experienced, so that the model gradually tends to be mature. For example, lu Zhanguo et al have fabricated a series of physical experimental models (including single fracture model, fracture network model, fracture hole model, etc.) covering fracture hole features using marble stitching method, and have conducted single-phase and two-phase fluid flow law experiments (Lu Zhanguo. Fracture hole medium fluid flow law study [ D ]. Chinese petroleum university, 2010) taking into account factors such as fracture opening, fracture structure combination, hole density, etc. The two laser etched organic glass plates with the slot holes are fixed and sealed by screws to manufacture various large-scale physical experimental models of the slot holes, and the oil-water distribution difference under the factors of different filling degrees, different bottom water intensities and the like is researched (Yang Jiang. Physical simulation research on the water injection development rule of the slot hole type carbonate reservoir in the area of Tahe 6-7 [ D ]. Southwest Petroleum university, 2016). Wang Shijie A full-diameter core is split in half, then a fracture-cavity structure is etched on the two half cores, and finally the two half cores are bonded together, so that a full-diameter etched core model (Wang Shijie. Fracture-cavity reservoir water flooding mechanism based on a real core etching model [ J ]. Proc. Nature science edition, 2011,33 (06): 75-79+207) is manufactured. Zhao Qing after a fracture-cavity structure is etched on a carbonate plate, sealing two sides by using an organic glass plate and a solid adhesive to manufacture a visual carbonate plate fracture-cavity model, and analyzing oil-water distribution differences (Zhao Qing, zhang Jianjun, ding Baodong, and the like) after water flooding and gas flooding by using the model. On the basis of a two-dimensional 3D printing model, gao Songyang et al use a reverse modeling method to manufacture a real three-dimensional karst cave model with various morphological structures based on an actual geological model, and monitor the distribution change of oil and water saturation in the water flooding experiment process in real time by a resistance method (Gao Songyang. The hole-seam model based on 3D printing is used for improving the water flooding mode to study [ D ]. Chinese Petroleum university (China east), 2019). The conventional fracture-cavity type oil reservoir simulation experiment device has the following two problems that on one hand, the experiment device is mainly limited to physical simulation of single-phase oil-water and oil-gas two phases, and a physical simulation experiment device and a technical method for oil-gas-water three-phase coupling flow are not formed yet, and on the other hand, simulation of a fr