基于FVCOM模型建立三维数值模型,对长江口深水航道整治工程的水动力和盐度进行三维数值模拟.在采用盐度实测数据对建立的数学模型进行验证的基础上,采用相同的洪季潮位边界及洪季河流边界,对比不同工期,长江口海域洪季盐度场分布情况,特别是南北槽的盐淡水交汇区域的变化情况.进一步分析深水航道沿程盐度垂向分布变化,说明不同工期盐水楔差异及变化规律.

The unit for characterization of fractured-vuggy reservoirs presents multi-scale feature and cannot be directly simulated by using numerical simulation software based on continuum mechanics.A new dynamic simulation model has been established for fractured-vuggy reservoirs with bottom water based on mechanics of fluid flow through porous media and the characteristic scale of reservoirs.The new model has realized coupling of discrete media and continuous media through special treatment of microfracture,macrofracture and cavern,thus proposed a suitable numerical simulation method for prediction of water flooding performance in fractured-vuggy reservoirs with bottom water.The effectiveness and feasibility of the method have been proved by calculation examples.

In order to further study effect of the permeability distribution on sweep efficiency in the process of water flooding development, the mathematical statistical theory of random distribution model was introduced into the reservoir permeability parameter field construction, combined with flow mechanism in the low permeability reservoir, the parameter field was modified. On this basis, the random distribution model of different permeability, the change laws of sweep efficiency under different development hole pattern, distribution features of injection-production streamline and remaining oil distribution were studied by using numerical simulation method. The field application showed that modified parameter field could better reflect the characteristics of low permeability reservoir heterogeneity. The effect of permeability parameter field generated by three kinds of random distribution models on the sweep efficiency was very large. Since start-up pressure difference existence, a large number of surplus oil flow region existed in low permeability reservoir at the late stage of development. Through appropriate increasing production pressure difference overcome startup pressure difference, let more remaining oil flow area participate in flow so as to effectively improve the recovery degree, but if the production pressure difference was too big, water breakthrough was easily caused.

Based on the characteristics of fractured-vuggy carbonate reservoirs in Tahe Oilfield as well as dynamic and static data from pilot production,visualized models of different combination of fractured and vuggy were built up through similar theory and forward modeling in this study.Comparison and verification of the reservoir space type of corresponding water cut law were done by physical simulation experiment.The result reveals the physical nature of water cut performance,and provides the experimental and theoretical basis for the efficient development of reservoir.The experiment simulation proves that there are five basic types of water cut performance in fractured-vuggy carbonate reservoirs.Each type is related to the specific reservoir geological characteristics,combination relations of vuggy and fracture,water energy and connection between aquifer and deposit.Compared to sandstone reservoirs,carbonate reservoirs have more complicated characteristics in water influx. The influx always happened in fractures and in the cave inside,and the oil-water interface levels up in horizontal position.The coupling of conduit flow and permeation is the direction of research in the future.

由于缝洞型碳酸盐岩油藏储层的复杂性,研究其注水替油的机理就显得很必要.在注水替油的过程中,溶洞未填充并且充满油时,若将水注入到溶洞内,由于油水的密度差异所产生的重力差异必然导致水下沉,产生油水分离,水逐渐占据了下部油的位置,从而油水进行了置换,达到注水替油的目的.所以,重力分离是注水替油中最主要的理论依据之一,因此有必要对油水两相由于重力作用发生分离的过程进行研究.通过物理模拟实验研究表明:注水过程中注入水在溶洞中发生置换作用、驱替作用和水洗油作用,对于孤立溶洞注水替油,置换作用,是注水替油的决定因素;随着注水替油轮次的增加,油水界面逐渐上升,近井地带的含水饱和度增加,产量递减趋势逐渐加快,井底流压呈指数递减,后期递减速度越来越快.

In its development process of the Kela-2 gas field under abnormally high pressure,as the effective overburden pressure is changed dramatically,the reservoir rock deforms easily to cause the porosity and permeability to become smaller,which will have a relatively great impact on the gas field development.Using the actual core in the Kela-2 gas field,the characteristics of stress sensitivity have been studied in laboratory experiments and the research predicted the change laws and affecting factors in the gas field development.Results indicate that in the Kela-2 gas field,the reservoir permeability and porosity are related to the power function with the effective overburden pressure,porosity change laws are relatively consistent and the porosity change intervals are comparatively small;the change of penetration rate is relatively complex:the lower the initial penetration rate of the rock is,with the effective pressure increasing,the sooner the decline rate and the greater the decline rate under the same effective pressure are.As the Kela-2 gas field has been developed with depletion-drive to the abandonment pressure,the reservoir comprehensive physical properties changed insignificantly,the absolute value of porosity reduced from 0.5% to 1.5% and the integrated penetration rate decreased by 18.2%;these changes have little effect on the production capacity of gas reservoir.

The effective well diameter mathematical model is established which is about gas well pressure transient analysis in the composite layer affected by mobility ratio of the inside by outside.Using the relationship of formation permeability and sulfur saturation,the pressure solution at the bottom hole of gas well is obtained affected by different sulfur saturations,and the solution can be used to draw the characteristic curve affected by different sulfur saturations and used to analysis the gas well pressure behavior and well test,and the influence of sulfur saturation on pressure behaviors is analyzed.This research offers the theoretical base of pressure behavior and well test analysis of gas well in sulfur gas reservoir.

The gas well productivity is the basis and foundation for gas field development plan design,gas well production allocation,surface construction and adjustment of development plan.The analysis of gas well productivity can predict the dynamics of gas wells accurately and investigate characteristics of gas bearing formation,which provide sufficient basis for developing the gas field in rational and scientific way.The abnormal productivity test curve and the negative slop appearing in some well data resulted from the characteristics of high single well production and sulfur blocking in some wells in the Luojiazhai and Puguang gas field of the northeastern Sichuan basin.Therefore,starting from seepage mechanics,after having analyzed the seepage model existed in high-sulfur gas reservoir,the productivity well test interpretation models,such as the additional epidermis model,the compound seepage model,have been established.Having processed the measured data of a well in the Luojiazhai gas field of the northeastern Sichuan basin with this model,it is proved that such model has guiding significance for production allocation of high-sulfur gas reservoirs.

According to geology specific fact of Xujiahe gas reservoir in western Sichuan region, the difficulties of hydraulic fracturing technology in deep tight gas reservoir is analyzed comprehensively. Besides, by systematic analyzing the problems of stimulation test case in 148 and 139 well, the corresponding countermeasures in many aspects such as decrease fracture pressure, quality of equipments and material and min-fracture test are given which could provide useful information to do it in deep gas reservoir at the next step.

针对缝洞型碳酸盐岩油藏的实际特点,对其水侵量计算进行了等效法、解析法和物质平衡曲线法等多种方法的研究,并对各种方法的适用性进行了对比分析.所提出的计算理论能够有效地应用于评价各种油藏水体形态下的三重介质缝洞型碳酸盐岩油藏水侵量,对开发此类油藏具有一定的理论价值和实际意义.

A mathematic model for describing percolation in vertical well in heterogeneous fractured-vuggy reservoirs was built based on fluid flow mechanics in porous medium.By using Lord Kelvin point source solution,Bassel integration and superimpose formula,boundary element fundamental solutions(BEFS) are derived for percolation in vertical wells in heterogeous fractured-vuggy reservoirs and a BEFS model of bottom hole pressure in vertical wells in heterogeneous fractured-vuggy reservoirs is also established.Log-log type curves of dimensionless pressures and pressure derivatives vs.dimensionless time are plotted through theoretical calculation;and the effects of wells located in different areas of high-permeability zones and high-permeability zones located in different parts of the reservoirs upon the bottom hole pressure behaviors are analyzed in detail.

Due to the complex distribution and fluid properties of the fractured-cavernous carbonate reservoir, it is difficult to precisely evaluate the reserves. As a result, no economic and effective development plan has been made so far. This paper discusses the current static reserves calculating method and develops a new dynamic reserves calculating method, which is more available to be applied to calculate the reserves in fracture-cavernous carbonate reservoirs. Taking Tahe Oilfield as an example, this paper mentions that the non-uniform distributed fractured caves cannot be exactly described and some geological parameters cannot be acquired based on the current reserves calculating reserves method, which results in the big errors of the reserves calculating results. Therefore, on the basis of the mass balance theory, this paper introduces a new dynamic method, which has no special requirements for the concrete forms and distribution of fractured caves and can analyze and evaluate the reserves of fractured-cavernous carbonate reservoirs more precisely without requiring too many parameters. The new method has been applied to actual oil reservoirs, proving that it is credible and accurate. It is of theoretical and practical significance to the development of similar reservoirs.

By utilizing the spatial analysis function of GIS,the computer,the communication network and the automatic control system,automatic information management can be realized and the whole production process can be dynamically monitored and scheduled with working parameters,pipeline information,and the mode of equipment operation.Based on GIS,this production scheduling system combines geographic information on pipeline and equipment,spatial information,a great variety of graph information,maintenance information,monitoring information etc and presents to the users the running state of pipeline and equipment.At the same time,by using the Supervisory Control and Data Acquisition(SCADA)system,it guarantees that the production of oil gas storage with transport runs economically and reliably,acquires real-time data on production and automatically controls all sorts of operating conditions.It combines forecast,statistics,quotas of economy and norms of technology with the practical situation to accomplish optimized control and rational disposition of the production of oil gas storage with transport.

Basing on the empirical equation of pressure stress-sensitive effect and the basic theory of fluid flowing mechanics in porous medium,a mathematical model for well testing analysis in homogeneous gas reservoirs is established with considerations of permeability sensitivity to stress,effect of wellbore storage,and skin effect.The perturbation technique and Laplace transform method are employed in the calculation of the model to study the features of percolation in stress-sensitive gas reservoirs and the influence of different stress sensitivities on bottom hole pressure behaviors during well opening and shut-in.The results show that along with the stress sensitivity of permeability increases,derivative curve may upturning higher during drawdown test,while the derivative curve may drop down during pressure build-up test.If the damage to permeability caused by stress sensitivity during drawdown/build-up test is irreversible,the permeability can not be fully recovered through pressure boosting and the degree of pressure buildup is still lower.

Jingbian gas reservoir is a reservoir with fixed volume and no side or bottom water. In the formation there exists relatively rich water zone that is subjected to influence of many factors and has negative effects on gas well production. In Jingbian Gasfield, the characteristic of the production well is low yield, fast depletion, and formation water produced on certain wells and varying significantly in quantity in different regions. By classifying the characteristics of water producing wells, this paper studies rich water zone distribution, formation and its impact on production wells and the effects on gas field development because of water production. Also, this paper studies the reasonable production scale and the technologies to keeping this scale in Jingbian gas field through the reservoir simulation. It states that not only high formation water production can be avoided and current development program can be realized by adjusting well pattern and developing proper production program suitable for production wells of various types but also optimum production yields can be obtained. Based on the studies, this paper recommends the reasonable production scale and technologies for steady production, which may be applied in the exploitation of Jingbian Gasfield.

Inter-well interference will greatly affect the well test curve.In this paper,a numerical well test method is presented to study the inter-well interference effect on the well test curve,which used PEBI grid and gave the discrete control equations of oil-water-phase flow.The flow model for pressure drawdown well test was derived,which takes the well-bore storage and skin effect into account.The flow models and controlling equations were coupled,finally.According to comparing and analyzing the result under three patterns of placing well show that log-log curves at early stage coincide with each other,but obviously changing at medium stage and last stage due to the effect of interference wells.And the more interference wells,the faster pressure of testing well draw down and the greater is up-warp extent of well test curves.

采油螺杆泵因具有较高的系统效率而日益受到重视。目前,国内外生产厂家对许多新型螺杆泵进行了大量研究。本文简述了螺杆泵的研发过程,介绍了螺杆泵生产厂家及其产品系列,系统地分析了国内外螺杆泵的新技术、新工艺、新材料的研究进展。针对目前存在的困难,指出了螺杆泵的研发方向。

Gas reservoir development indicates that edge water drive gas reservoir is much lower in recovery efficiency compared to fixed volume gas reservoir. It has remained a challenge of gas development how to enhance edge water drive gas reservoir recovery efficiency. This paper analyzes edge water drive gas reservoir gas-water two phase flow characteristics and mechanism affecting recovery efficiency, then points out that the main factors which affects its' recovery efficiency are abandonment pressure and water invasion index. To increase recovery efficiency, traditional methods have been used to control the development rate and conserving reservoir energy in order to prolong water-free gas production period and control edge water cut rate, which eventually brings about high abandonment pressure and low recovery efficiency. Therefore, it is presented a new point of view, that is, high recovery efficiency for edge water drive gas reservoirs can be achieved by speeding up development, reducing low abandonment pressure, and increasing big water invasion index. It is demonstrated that proposed viewpoint is feasible in theory and exemplifies with real edge water gas reservoir calculation, and the correctness of the approach can be indicated by the outcomes.

Aiming at the problems of the complicated seepage flow mechanism in horizontal well and the difficult for analyzing transient well test data, on the basis of establishing its mathematical model and getting its solution, the paper presents the typical well test curve used to identify each flow stage 、 analyzes seepage flow character, gives out the expression of reservoir parameter by using the characters of each flow stage and demonstrates the rationality of this method. The characteristic value method on analysis for horizontal well test is simple and useful which enriches and develops the theory and method of horizontal well test.

Based on uniform flux analytic model of Ozkan and Raghavan,this paper establishes a computational model of infinite-conductivity horizontal well transient pressure,with discrete numerical method and semi-analytic to calculate transient flux distribution and well- bore pressure.The results indicate that infinite-conductivity horizontal well transient pressure is influenced by variable flux,but it doesn't appear early well-bore radial flow characteristic.The method has flexible extend mechanism and is a fast tool for completed well optimization and inflow performance forecast.