- 目录
### Analysis of Random Characteristics of Seepage Fiel

#### WANG Fei, WANG Yuan

##### Seepage field, Random field, Discretion of local average, First order Taylor series stochastic finite element method

The paper have analyzed and discussed the 3-D steady seepage field by SFEM. Based on first order Taylor series stochastic finite element method, the formulas of response variables (water level and hydraulic gradient) in stochastic seepage analysis are deduced, and then the stochastic analysis of seepage field is performed, and the relevant program is developed. The permeability tensor of infiltration domain is dealt with 3-D anisotropic random field and vector separable local average method is adapted to discretion of random field, the random variables derived by discretion will be various if the parameter is selected with different values. Finally, an example is given, and the results of random seepage field are derived in cases with different number of variables. Comparison with the results which are derived if the permeability tensor is only dealt with random variables, the feasibility of the proposed approach is proved.

### A Novel Method for Tortuous Stream Tubes in Porous

#### WU Jinsui, YIN Shangxian

##### Tortuosity, Permeability, Fractal, Radius of particle

In this paper a novel fractal method for measuring tortuosity is derived based on the definition of tortuosity and the relation of permeability and tortuous stream tubes in porous media. The tortuous stream tubes in porous media are expressed as a function of porosity, fractal dimension and the radius of particle. There is no experimental constant in the function and the theory is verified by the experiment easily.

### Study of Fractal Parameters in Porous Media

#### KONG Xiangyan, LU Detang

##### Flow in porous media, Fractal dimension of capillary diameters, Fractal dimension of fracture widths, Low-permeability reservoir, Fractal dual-media

This paper presented the mathematical formula of fractal permeability and fractal porosity along with their dynamical meanings. Starting from the available study of tortuosity in natural porous media, the varying range of fractal dimension of tortuosity is calculated. By analysis of scaling law and comparing with the relativity of inhomogeneous capillaries (or fractures), fractal dimension of capillary diameters and fracture widths are studied. The calculation method of permeability and porosity of inhomogeneous capillaries (or fractures) for classical flow study in porous media is discussed as well. At the end of the paper, a fractal model for porous dual-media is proposed, which provides a new method for the study of compact reservoir.

### Research on High Temperature Compound Gas Drive Oi

#### LIU Yifei, FAN Yao

##### Heavy oil, Steam drive, N2, CO2, Non-Newtonian

Based on the analysis of the viscosity-temperature characteristics and rheological characteristics of heavy oil, this paper systematicaly investigates seepage characteristics and oil displacement mechanism of exploiting heavy oil by steam drive and high temperature compound gas drive. The experimental results indicate that, according to the displacement efficiency from strong to weak, each displacement method can be ranked as following: compound gas (steam, N2 and CO2) drive, compound gas (steam and N2) drive, compound gas (steam and CO2) drive, steam drive. The main stimulation mechanism of high temperature compound gas drive is to reduce viscosity by heating, to improve the sweep efficiency, to improve oil phase permeability and oil-water mobility ratio, to maintain and enhance formation pressure, to expand heavy oil volume and so on. The results of this research provide theoretical criterion for application of high temperature compound gas drive in heavy oil field.

### Study on the Occurrence Status of Formation Water

#### YANG Zhengming, GUO Hekun, JIANG Hanqiao

##### Volcanic gas reservoir, Nuclear magnetic resonance, Formation water, Water vapor, Free water, Occurrence state

Volcanic reservoir is now one of the main exploration and development fields of natural gas in China. Nowadays, there are lots of new discoveries in Songliao basin, Zhungeer basin, Bohai gulf, etc. The reserve is over 3 thousand billion cube meters. It is a very hot focus in the field of exploration and development. In this study, the content of the water in volcanic reservoir is quantitatively estimated through nuclear magnetic resonance under different temperatures. The result shows that this method for estimating the content of water is feasible and the experiment is easily operated. Water exists in two kinds of state in volcanic reservoir, free water and water vapor. The content of water vapor is related to the temperature of the gas reservoir. The higher the temperature is, the higher the content of water vapor.

### Study on Improving Coal Penetrability with Water P

#### ZHANG Yinghua, HUANG Zhian

##### Methane, Water pressure blasting, Coal seam, Penetrability

The characters of water pressure blasting, traditional crack- made by infusing and traditional crack- made by blasting are analyzed and the mechanism of water pressure blasting which cause split in coal seam is also analyzed. The field test of water pressure blasting was carried out in Niuerzhuang coal mine of Fengfeng mining bureau. The attenuation rule of natural flux and the change of methane from the hole pre-and-aft blasting were observed. Finally the test results have proved that water pressure blasting is the better method to improve the penetrability of coal seam effectively and the pump flux of the hole pre-and-aft blasting increased 3 times.

### Recovery Ge from Pulverized Fuel Ash Through the M

#### PU Shikun, LAN Yaozhong, LI Yanjun

##### Pulverized fuel ash, Sulfuric acid, Ammonium fluoride, Sodium chlorate, Ge extraction

This paper has conducted conditional tests and discussion on the process parameters which will influence recovery of Ge from pulverized fuel ash, including the dosage of Sulfuric acid, ammonium fluoride, sodium chlorate, tannic acid and extraction time to find out the prior controlling condition of Ge recovery. Under this prior condition, leaching rate of Ge is as high as 84%, and tannic sinking rate of Ge is as high as 98%. The pulverized fuel ash, after recovering Ge, can be used to backfill the mine pit, besides, most of the lixivium after recovering Ge can be recycled, and the rest of it will be released after neutralized up to the standard by lime. This process enjoys the following quality: higher Ge recovery rate, less time used during the process, less consumption of auxiliary material, easier to control the process, avoiding the potential pollution on the environment and lower cost involved in it. Therefore, it is a kind of efficient and economic process of recovering Ge from pulverized fuel ash.

### The Drag Reduction Performances of Surfactant in M

#### SONG Fuquan, ZUO Jiachuan, WANG Jiandong

##### Surfactant, Drag reduction, Hydrophilic, Hydrophobic, Micro-channel

The characteristics of drag reduction of surfactant for deionized water in micro-channels are analyzed by experiments in which Cetyl Trimethyl Ammonium Bromide (CTAB) was used as the adsorption in this paper. The experiments show that the flow rate of water in micro-channel without CTAB agrees with the prediction of the conventional Hagen-Poisseuille equation. However, the flow rate in micro-channel increases clearly after CTAB being adsorbed. This indicates that the friction of water flow reduces 6.3% in micro-channel after CTAB being adsorbed in micro-channel with 50 micron diameter. The reason is that the adsorption of CTAB changes the wet ability of micro-channel from hydrophilic to weak hydrophobic, and there is flow slippage at the interface between solid and liquid. The relation between the efficiency of drag reduction and the time of adsorption is also studied, the results suggest that: there are a maximum in the adsorption of CTAB, and there are two steps in the course of adsorption: mono-layer adsorption and double-layers adsorption. The wettability of micro-channel changes from hydrophilic to weak hydrophobic in the course of mono-layer adsorption, and the efficiency of drag reduction will be the most value for saturated mono-layer adsorption.

### Effect of Groundwater Seepage on Heat Transfer in

#### WU Jianlin, ZOU Zuxu, GONG Jing

##### Heat transfer models, Analysis of groundwater advection, Affecting of ground-loop heat exchanger

This paper reviews the heat transfer model and calculation methods on the ground-coupled heat pump (GCHP), and found that almost all the model did not consider the influence of groundwater seepage, although groundwater seepage on the pipe heat exchanger has a big influence. Based on the theory of groundwater seepage and heat transfer theory, a new mathematical model coupled with groundwater flow and heat transferring between heat exchanger and ground soil mass are established, which conceded of the heat conduction and the role of the common groundwater seepage of infiltration coupled heat transfer model, which can provides a theoretical support for the calculation and analysis of ground-coupled heat pump heat exchanger.

### esearch on Effect Law of Protected Coal Seam Perme

#### BI Yewu, LIANG Bing

##### Protective coal seam mining, Permeability, Numerical simulation, Coal and gas outburst

To obtain changing law of protected coal seam permeability induced by mining protective coal seam, a number of numerical simulation tests were carried out using the numerical analysis code FLAC3D to investigate stress distribution of surrounding rock of protective seam. The results show that the more mining length of protective coal seam in a cetrain length along tilt direction, the higher permeability of upper and lower protected coal seam. Influence degree to permeability of lower protected coal seam is less than upper protected coal seam induced by mining protective coal seam. The largest influence area is located at the above middle position of goaf along inclination direction in mine area. This result has important guiding significance in precaution and treatment of outburst of coal and gas.

### Research of Nonlinear Flow Numerical Simulation of

#### YU Rongze, YANG Zhengming

##### Ultra-low permeability reservoir, Nonlinear flow, Reservoir numerical simulation, Seepage, Well pattern

According to the seepage characteristics of ultra-low permeability reservoir, the nonlinear flow numerical simulation software for ultra-low permeability reservoir is developed. The unit of the inverted nine spot well pattern of Eastern 16 block of Daqing Yushulin Oil field is taken as the research object. Under the condition of keeping the bottom hole flowing pressure of the production wells and water injection wells constant, the simulation of the formation pressure gradient distribution is made under different Producer-injector Spacing by using the numerical simulation software. At last, different fluid flow region, effective driving pressure system and reasonable well pattern deployment are achieved to provide references to the well pattern arrangement of the injection and production wells for this kind of ultra-low permeability reservoir.

### Application of Visual MODFLOW on Groundwater Resea

#### ZHANG Ye, LV Lin, CHAI Yabin

##### Groundwater, Water saving as resources, Groundwater model MODFLOW, Reduced exploitation

In this paper, chief work contents and methods on Tianjin groundwater research by GEF are introduced, and several issues that should be of great importance during the work are discussed. It is considered that the keys of a successful project are: the complete implementation of the concept of water saving as resources, the application of groundwater model, MODFLOW and remote sensing technology and taking the working way of integration.

### A Comparative Study on Enhancing Oil Recovery of C

#### ZHANG Shuo, SHAN Wenwen

##### Gas MMP, Near miscible displacement, EOR, Low permeability

Efficiency of oil recovery with water flooding process is poor in low permeability oil reservoirs. By contrast, gas flooding is an efficient technology to improve oil recovery of such reservoirs. Considering good results of previous miscible displacements, experiments of physical model are performed by using the long core flow test, and variations of recovery factors and pressure are obtained under the different flooding processes in miscible pressure condition. In this paper, it includes pure gas flooding, pure water flooding, gas flooding after water flooding, water flooding after gas flooding and WAG. The research will provide the principle for selection of reasonable development manner of low permeability reservoirs and basic data for further numerical simulation.

### Numerical Simulation of Influence of Different Tim

#### ZHENG Chao*, LIU Jianjun

##### Steam huff and puff, Casing stress, Thermal-Mechanical coupling, Numerical simulation

The influence of different time of shutdown on casing stress in thermal recovery well was studied by numerical simulation based on theory of thermal-mechanical coupling. The simulation results showed that the longer the time of shutdown, the greater the decline in value of casing stress, then the casing stress was greater when continuing to inject steam to the stabilized state of the casing, so the shutdown had greater impact on casing security. The simulation results are very helpful to choose a reasonable time of shutdown and the casing protection in oil fields.

### Calculation of Earth Pressure on the Condition of

#### TONG Huawei, CHEN Haiying

##### Excavation, Seepage, Earth pressure

Non-water-proof retaining structure is often adopted when excavation is carried on in thick clayed soil layers with low permeability. So the impact from the groundwater seepages should not be ignored on the calculation of the earth pressure. When the seepage exits in clayed soil layers, a larger deviation occurred between standard calculation and the measured value of earth pressure. Seepage path on both sides of excavation are took into account in this paper, and a new calculation method for the earth pressure is obtained under the terms of seepage in non-waterproof retaining structure.

### The Research of Unsteady Seepage Flow Based on Sat

#### FU Junfeng, JIN Sheng

##### Saturation, Unsteady seepage, Saturated and unsaturated seepage, Finite element method

In this paper, a numerical model simulating the unsteady seepage flow through aquifer was presented and it used two variables: saturation and water head to describe the seepage domain. Experiments of unsteady seepage flow through dam were conducted in laboratory and provided data to verify the model. The performance of the model was also assessed by comparing with analysis solutions. The examples have proved that the accuracy and reliability of the model to deal with seepage flow problems with complex conditions. It also has demonstrated that the method of confirming the seepage face through the saturation description is natural and logical in physical concept and actual application. The method predigested the computing scheme, comparing with those tradition methods.

### Coupling Thermo-hydro-elastodynamic Response Model

#### LIU Ganbin, YE Junneng

##### Thermo-hydro-mechanical, Dynamic response, Cavity, Laplace transform

In this paper, an attempt has been made to investigate the thermo-hydro-elastodynamic response in porous elastic medium with a cylindrical cavity that is subject to a time dependent thermal/mechanical source. To obtain the analytical results, a fully coupled thermo-hydro-mechanical model is introduced, the numerical results are also performed by using the technique of Laplace transform and are used to analyze the nature of variations of the field variables, i.e. the coefficient of thermo-osmosis, and are compared with the dynamic response results of thermo elasticity to ascertain the validity and the difference between two models.

### Coupled Model of Gas Flow–Solid Distortion in Coal

#### YANG Tianhong, CHEN Shikuo

##### Gaseous coal, Gas permeability, Gas-solid coupled model, Numerical simulation, Gas pressure relief

On the basis of seepage theory of gas flow in coal seams, elastic theory of coal deformation, together with the coupling relationship between gas permeability and porosity, a mathematical model for coupled gas flow in coal collieries was established. By using the gas flow model, the mining induced pressure relief, the gas pressure changes, gas drainage, the associated characteristics of gas permeability and gas pressure in coal seam during mining were numerically simulated. The numerical simulations are helpful for understanding the gas drainage mechanisms and taking effective measures to prevent the occurrences of gas outbursts in collieries.

### The Study on Time-dependent Permeability of Fractu

#### DU Xinlong, KANG Yili, YOU Lijun

##### Permeability, Time-dependent, Effective stress, Fracture, Micro-bulges, Pressure solution

The permeability of fractured core decreases not only with raising the effective stress, but also with time. In this paper the core flow test had been conducted by use of the outcrop with different fracture width from western Sichuan basin, the test fluids were nitrogen and brine (3% KCl). The study shows that the decrease of permeability is up to almost 48% and the time of equilibrium is more than 1.5 hour under the 3MPa effective stress. But when the effective stress is 10MPa, the decrease was below 30% and the time of equilibrium is less than 1 hour. And the reduction of time-dependent permeability tested with gas (nitrogen) is below 15% when effective stress is 3MPa; however the permeability tested by brine decreases as much as 48% under the same effective stress. The study analyzes that the saturated core fracture has been propped by micro-bulges, which are easier to be embedded into each other and slide. In the process of fracturing, the fracture surface becomes weak consolidation, this can cause fine migration. The hydrated clay minerals on the fracture surface have a buffer effect, so the stress could not be fully loaded immediately. In addition, some minerals such as feldspar on the fracture surface could be dissolved during the brine flows through the fracture under higher effective stress; this can cause the aperture to become smaller. During the development of the reservoir, the accumulated water in the fracture and the working fluids should be withdrawn as quickly as possible. And in the processes of formation damage assessment, the effect of time-dependent permeability should be eliminated as much as possible.

### Evaluation of Sealing Ability of L Gas Field Under

#### HU Shuyong, LIU Xue, HUANG Jing

##### Underground gas storage, Sealing ability of cap rocks, Lateral sealing ability of faults, Vertical sealing ability of the faults, Shale smear factor algorithm

Gas storage is an important means to realize natural gas reserve and energy security. For underground gas storage, gas can be stored in a reservoir and kept for a finite time as required. Evaluation of sealing ability of abandoned gas field is a key factor to underground gas storage reservoir successfully. And the most important indicators are the sealing properties of faults and cap rocks. L gas field which has two faults was an abandoned gas field and has been constructed as gas storage reservoir. The sealing ability of the cap rocks is macroscopically evaluated by comprehensive geologic analytical method and microscopically evaluated by a series of experiments. Moreover, two sets of fault lithology connection relationship are considered to evaluate the vertically and laterally sealing ability of the faults. At the same time the shale smear factor algorithm is applied to quantitatively evaluate the sealing ability of the faults. All the evaluation results show that the sealing ability of the fault and cap rocks can fulfill the requirement of the gas storage.