توجه: محتویات این صفحه به صورت خودکار پردازش شده و مقاله‌های نویسندگانی با تشابه اسمی، همگی در بخش یکسان نمایش داده می‌شوند.
۱A Detailed Modeling for Enhanced Fluid Percolation in Fractured Porous Media by Application of Low_ Frequency Elastic Waves: An Extension of Previous Models to Fractured Reservoirs
نویسنده(ها): ، ، ،
اطلاعات انتشار: ششمین کنگره بین المللی مهندسی شیمی، سال
تعداد صفحات: ۶
Application of elastic vibration technologies in fluid flow through porous media is outspreading day after day, but lack of knowledge about the governing mechanisms is the Achilles heel of this technology. During past few years, models for predicting the flow behavior under radiation of elastic waves have been presented for granular porous media by geosciences Researchers. But till now, no mathematical model is presented to be applied in fractured media. This will be more noticeable when we bear in mind that several reservoirs in Middle East region are fractured. In this work the current model applied on granular medium is extended to fractured systems, and the effects of elastic waves on capillary trapping and mobility of Bingham plastic fluids in fractures have been investigated. Eventually, a model for predicting the influence range of the wave in fractured reservoirs is presented. Oil is considered as Bingham plastic and water as Newtonian fluid. The Gravitational forces are assumed to be negligible and the wave range of frequency is considered below the critical frequency in fractured reservoirs, 100 Hz. So, the time derivation in modeling of wave propagation could be neglected. The results of this study clarified that radiation of wave with low frequency and intensity extremely increases the flow rate and decreases the minimum pressure gradient required for flow of Bingham plastic fluids in fractured porous media. In addition, the fractional flow of Bingham plastic fluid is increased dramatically.<\div>

۲Ultrasonic Waves Effect on Removing Skin from Near Wellbore Region: A Modeling and Experimental Approach
نویسنده(ها): ، ، ،
اطلاعات انتشار: ششمین کنگره بین المللی مهندسی شیمی، سال
تعداد صفحات: ۷
Although the concept of high frequency acoustic waves, for improving production from oil wells have been applied from many years ago but yet the mechanisms related to this method are not well understood. Nowadays, ultrasonic waves are applied to remove skins formed near wellbore due to asphaltene deposition and fine particles. Despite the fact that there is no document about ultrasonic wave effect on removing gas condensate in field scale studies, but it seems that this method can be used for solving this problem as well. Different mechanisms can govern these removalprocesses through porous media in the presence of ultrasonic field. In this paper at the first part we are going to study the effects of ultrasonic wave irradiation on relative production increase by removing phase trap induced skin due to gas condensate formation near well bore by reducing interfacial tension. To this aim firstly a mathematical model of wave influence on interface of fluids is proposed then in experimental part a modified pendant drop setup is employed and a wave generator with varying output power, 55 to 100 watts, and a constant frequency of 45 kHz is applied. It is illustrated that how ultrasonic wave’s radiation could change the shape and volume of drops of oil ejecting from capillary tip which is a simplified pore in our experiment. Also it is observed that we have about 10 to 15 percent increases in cumulative production from a capillary tube at the presence of ultrasonic field. At the second part of this paper, based on the trend of viscosity versus time curves under ultrasonic wave field, resolution and scattering of asphaltene aggregates is concluded and it is confirmed by visualization under microscope based on buckley previousworks on asphaltene instability analysis.<\div>

۳Precision Evaluation of RPCs in HRSI Orientation of Geoeye_1
نویسنده(ها): ،
اطلاعات انتشار: پنجمین کنفرانس بین المللی پیشرفتهای علوم و تکنولوژی، سال
تعداد صفحات: ۹
Nowadays physical and abstract mathematical models are used with pushbroom satellite imagery, the imagery vendors do not provide ephemeris data (or ancillary data) for the end users, so one has to rely on mathematical sensor models for extracting 3D geospatial information. Rational functions are often applied in photogrammetric and remote sensing processing to represent the transformation between the image space and the object space whenever the rigorous model is made unavailable to the users intentionally or unintentionally. The RPC sensor model is considered to be a simple and effective way to approximate a rigorous camera model. However it has been seen that using RPC without the aid of ground control points contributes to geo positioning errors. This can be corresponding to terrain inherent interior and exterior orientation errors in the rigorous sensor model. These errors in geo positioning can be compensated by additional parameters in the image space that affect a translation of image coordinates. Therefore one needs to refine the supplied–RPC to achieve higher accuracy.This study reviews the developments in ground point determination from HRSI via the model of rational polynomial coefficients (RPCs). For geometrical accuracy improvement, the RPC sensor models by applying control points will be corrected.The potential for RPC block adjustment to yield sub–pixel geo positioning accuracy from HRSI is illustrated using results from experimental testing with two Geoeye_1 stereo images. Finally error propagation issues in RPC block adjustment of HRSI in various methods (supplied–RPC, supplied–RPC with compensated bias, generated RPCs with users) are considered.<\div>

۴Report of a Documented Case of Encapsulating Peritoneal Sclerosis in Iran
اطلاعات انتشار: گوارش، سال
تعداد صفحات: ۵۵
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