Tag Archives: modeling
In geophysics, one of the most important areas isgeothermy – science about the study of the thermal field of the Earth. One of the main problems of geothermy is to determine the undisturbed temperature of rocks. The geothermal field parameters (natural rock temperature, geothermal gradient, heat flux) can be used as search attributes of oil and gas deposits. Knowing the natural temperature of rocks is also necessary for wellbore thermal data interpretation. In borehole thermometry, the geothermal distribution as the unperturbed natural rock temperature is the background in the detection and analysis of temperature anomalies associated with productive layers and casing integrity damage. Today, there are no generally accepted methods for determining the unperturbed temperature of rocks. The methods used in practice have a number of problems and allow only to estimate approximately the natural temperature of the rocks. When drilling, the temperature field in the surrounding rocks varies and it takes a considerable time to restore it. This process can continue from a few days to several months-in the case of deep wells, so the natural temperature of the rocks can be measured directly only in a small amount of long time of idle wells.
The known methods for determining equilibrium temperature of rocks are analyzed in the article. A new method based on recording the non-stationary temperature in the well after stopping drilling and determining the equilibrium temperature of rocks based on the use of a simulator of non-stationary temperature in drilled wells is proposed. The mathematical model of the simulator, the formulation of inverse problems and algorithms of their solutions are discussed.
Underground main oil pipelines are very extended objects which pass not only through stable areas with steady soil, but also areas with active manifestations of soil changes, including through bogs, the rivers, seismic breaks, is long-term – frozen soil, sites with karst manifestations, slopes and ravines. At long operation of pipelines on such sites it is necessary to watch the happening changes and to take anticipatory measures for safety of pipelines.
In article research of dependences of interaction of the pipeline with soil in a landslide zone from various factors is considered. The problem is solved by method of physical and mathematical modeling. The model of interaction of the pipeline with soil in a landslide zone represents a valuable contribution to the solution of the actual scientific and technical problem connected with safety of pipeline systems.
As a result of work the state equation in the form of the differential equation is received. Methods and features of the decision in some simple cases when reaction of soil is expressed by analytical expressions are investigated. At determination of tension from external forces difficult correctly and precisely to describe regularities of interaction of a pipe with soil which besides change at soil changes. Other complexity that in many cases boundary conditions for the considered pipeline site are in advance unknown; they are defined only during the solution of a task. Therefore in article decision methods in real cases when reaction of soil can’t be described by means of simple analytical expressions are considered. For these cases the algorithm based on numerical methods with consecutive approximations is made.
Electronic training complexes play an important part understanding of new studying material. They help to understand the complicated processes that are often hidden from view. Various operations connected with the calculations, drawings and visual representation of the object cause difficulties. There are several types of electronic training complexes, their aim is to systematize educational material, mathematical calculations and modeling of mechanical and technological processes.
Owing to the three-dimensional modeling electronic training complexes give information, allow to observe the mechanical processes, to examine technical device of machines and apparatus.
For solving the problem of mechanical gears visualization the variant of training complex is suggested. It is a collection of the main types reducers’ dismantling video demonstrations.
In the work the main stages of computer program are analyzed development.
The gear models were created in program “Compass 3D” with the help of three-dimensional computer modeling. Their usage helps to demonstrate mechanism dismantling. An interface of the complex, allows a user to select the desired gearbox for visualization.
An application of training complex will help to solve the problem of the mechanisms’ spatial representation and to optimize the studying process of the subject “Machine parts and bases of designing”.
In order to lower the risks in the processes of field development and waterflooding systems planning geologic and simulation models are built on the base of core material examinations, geophysical well logging (GWL) and seismic survey, flow well test (FWT), downhole samples. The crucial moment in simulation is the integration of all methods available of data obtaining that will allow constructing the best detailed and accurate geologic and simulation model, as the disadvantages of one method are compensated by the advantages of another and allow forming the notion of the object under study. The given article is devoted to studying causes of variety of uncertainties that arise during construction of geologic and simulation field model.
Within the work the causes of arising uncertainties have been classified according to the type of measurement (direct or indirect), the scope of research by area, the vertical resolution capacity, and according to the nature of uncertainties causes. They, in turn, are subdivided into measurement problems (equipment error and non-compliance with measurement procedures) and problems of application in modeling (interpretation problems and problems of constructing the model).
In order to reduce uncertainties we can define two possible ways. The first is minimisation of uncertainties in the frames of a separate method. The second way is the integration of all available information in a manner of reducing the uncertainty band by means of measurement’s mutual constraints, imposed on each other, i.e. the use of complex system approach to applying initial data obtained by different methods.
Instant assessment of field-geologic information and taking it into consideration when correcting geologic and simulation model allow producer to acquire practical instrument for operating and, if necessary, adjusting field development process, which includes taking into account location of the zones of remaining oil reserves the possibility for developing scenarios of enhancing reservoirs’ recovery, performing justified calculations of forecasts of production and financial risks reduction.
Under the optimization of technical systems generally understood comprehensive selection variable (technical) indicators system to achieve the most advantageous in terms of its functioning, factors. In fact, optimization is the aim of uniting the processes of monitoring and control tasks are for technical hydraulic systems were considered in the first chapter. Proposed model for the calculation of the flow distribution in addition, allows you to control, manage and design systems for reservoir pressure maintenance (RPM), makes it possible to optimize it in some way. As is known, the whole system operation is determined and its operational targets. Typically, the optimization of reservoir pressure maintenance systems begins with the design phase in the selection process of operational properties of objects and structures transport hydraulic system (THS). Performance properties are selected primarily on the basis of compliance with the established regimes injection project to develop standards; secondarily, on the basis of minimum capital costs of the structure , and the third , from the minimum operating costs of individual objects , and the system as a whole. Optimization of reservoir pressure maintenance systems by changing the structural scheme rests on the mental apparatus of man. Ie currently automate this process quite difficult, as in the selection and construction of one or another variant of the block diagram should be guided by a plurality of source and output data. In addition, each option should be clearly "thought" (analyzed), taking into account not only the parameters of the simulated system, but also a variety of other limiting factors. Naturally, to automate the process of structural optimization should solve the problem of "artificial intelligence", and that at this stage it is not possible. So here we touch only aspects of the optimization state of the system by changing the performance of the individual to control the most important elements. .