bluuebunny/crossref_metadata_2025_split huggingface dataset:
Synthetic Fluid Selection for High-Pressure Gas Condensate Flow Tests
Authors: Singh Kameshwar , Whitson Curtis Hays 
Published: March 2017

Abstract
High-pressure steady-state flow tests on gas condensates are needed to determine relative permeabilities and their dependence on capillary number. Such experiments require large quantities of reservoir fluids. Other laboratory challenges using reservoir fluids include H2S content and high temperatures.
This paper presents a method that has been used successfully to create synthetic hydrocarbon mixtures that closely mimic reservoir fluid PVT, viscosity and IFT behavior at relevant reservoir pressures. The synthetic mixtures typically consist of 3-4 hydrocarbon compounds, and are readily created in the laboratory in large quantities.
The selection of a synthetic mixture starts with a known description of reservoir fluid PVT properties, from laboratory measurements and/or EOS modeling. Typical PVT include constant composition and constant volume depletion data, viscosities, and gas-oil interfacial tensions (IFT).
The procedure for creating an appropriate synthetic fluid that mimics the reservoir fluid PVT behavior is selection of 3-4 available hydrocarbon compounds, always consisting of methane, at least one light intermediate (C2 to C10), and at least one heavy compound (most often Diphenylmethane DPH-C1). An automated selection process has been developed. We used the SRK EOS with zero BIPs (binary interaction parameters) to describe phase and volumetric behavior of the synthetic fluid system.
With a given group of selected compounds, the amount of each compound is determined by regression to minimize the mismatch between synthetic fluid PVT and reservoir fluid PVT. The synthetic mixture component slate that gives the best match is then chosen from the many possible combinations.
This method has been used for some twenty reservoir gas condensates during the past 15 years. In this paper we illustrate the method for some twelve "public" reservoir gas condensates ranging from lean- to rich fluids, with some containing significant H2S and CO2 content.
The accuracy of synthetic fluid mixtures to mimic actual reservoir gas condensate behavior is surprisingly good. Laboratory applications of the methods presented in this paper have been made without experimental difficulties. In general, the modeled synthetic fluid PVT behavior predicted by an EOS are quite close to the measured laboratory PVT of the synthetic fluids.
The paper provides, for the first time, documentation that 3-4 component synthetic mixtures can be used to represent reservoir gas condensate fluids covering a wide range of composition and PVT behavior.
Study of Slip Flow in Shale and Tight Gas Reservoir Rocks Using Lattice Boltzmann Method
Authors: Moghaddam Rasoul Nazari , Jamiolahmady Mahmoud 
Published: March 2017

Abstract
Development and production from unconventional resources require understanding of flow mechanisms and rock/fluid interactions, which are different from those in conventional reservoirs. Several flow regimes including continuum, slip and transition can dominate the fluid flow in these reservoirs due to the presence of various pore sizes from micro to nanoscale. Accurate prediction of flow behaviour requires suitable simulation techniques for modelling the flow regimes active in unconventional reservoir rocks. Recently, the lattice Boltzmann method (LBM) has received great attention as a well-accepted method for the simulation of fluid flow in nanoscale systems. However, the impact of different boundary conditions to model such fluid-rock interactions have not been investigated so far. In addition, the LBM simulation results have rarely been compared with the experimental data.
In this study, the two-relaxation-time (TRT) based Lattice Boltzmann approach was adopted to simulate the gas flow in nanoscale single pipe. Different boundary conditions including bounce back, specular reflection, diffusive reflective and bounce back-specular reflection (BSR) were used to capture the gas slippage at the wall surface. For validation, the simulation results were compared with the results of other simulation techniques such as Direct Simulation Monte Carlo and Information Preservation methods reported in the literature. After validation, the impacts of different boundary conditions and various tangential momentum accommodation coefficients (TMAC) were studied. In addition, gas flow in a simplified porous medium (a system of pore body/throat) was modelled and the simulation results were compared with those obtained for gas flow in a single channel. Furthermore, the simulation results of gas flow in a single channel and in the simplified porous medium were compared with the scaled experimental data measured on three shale rock samples.
The results show that, among different boundary conditions, BSR is the most suitable one for gas flow simulations in shale rock samples. However, the LBM simulation with the BSR boundary condition using the TMAC literature value of 0.8 underestimated the permeability enhancement (due to gas slippage) in these shale rocks. It was found that a TMAC value of 0.6 could better estimate the permeability enhancement. It was also shown that the characteristic length of porous media could be better described by the average of "pore throat" rather than "pore body" sizes. Moreover, the permeability was overestimated for Kn&gt;0.1, when the gas flow was simulated in a single micropipe or microchannel rather than the considered porous medium.
The results obtained in this study can be used for more realistic predictions of shale matrix permeability, when the slip or transition flow regime is dominant. It also improves our understanding of using LBM for simulation of fluid flow in unconventional reservoir rocks.
STACK Well Performance, a Multi-Pad Completion Comparison
Authors: Van Sickle S. , Galloway J. , Owen T. , Wearly J. , Snyder D. 
Published: March 2017

Abstract
An operator working in Oklahoma's STACK play continues to analyze its completion program in an effort to identify the optimal balance between cost-effectiveness and production. A recent study of field results from four pads with two different completion methods on each pad, shows a difference in fracture performance between the two methods, as well as resulting production.
Each of the four well pads was developed with one ball-activated uncemented multistage completions and a cemented liner completion using either sliding sleeves or plug-and-perf. The methods on each pad targeted the same horizon in the STACK play, which is made up of multiple formations.
The wells on each pad were stimulated with the same treatment program, and the performance of the wells was analyzed using microseismic, sidewall cores and extensive logs. Additionally some of the pads were also tested with diverter. Daily OWG rates were also reviewed, and a cost comparison between the two completions on each pad was conducted.
The STACK play is predominantly completed using plug-and-perf methods. These wells have long laterals and are typically stimulated with large amounts of fluid and proppant. All the wells in this study were completed with common stimulation programs for the area. Despite the typical estimated frac length, three of the subject wells experienced offset stimulation interference from offsetting wells or pads. These "frac hits" contributed negatively on the producing wells for a period of time.
On all the pads, the wells completed using uncemented multistage completion systems had lower CAPEX Quicker completions and easier millouts helped contribute to the lower upfront CAPEX. The uncemented multistage wells also flowed back initially at higher rates.
This paper compares a new completion method attempted in one of the most active plays in the United States. As well as the diagnostic, completion and cost comparisons, the impacts of a "frac hit" on producing wells and suggestions to reduce negative outcomes from the hits will be discussed.
Systematic Uncertainty Analysis and Management in Waterflooding Development for a Large Sandstone Reservoir in Middle East
Authors: Yong Li , Changbing Tian , Baozhu Li , Yixiang Zhu , Benbiao Song 
Published: March 2017

Abstract
For reservoir development study, there are a lot of uncertainties in different research aspects. But if these uncertainties are ignored, reservoir performance could be much worse than expected because of wrong development options possibly selected and applied. Therefore, uncertainty analysis should be addressed during reservoir development study, and uncertainty parameters should be analyzed and their impact should be evaluated in order to reduce the corresponding risks. The paper proposes that uncertainty analysis should run through the whole study process of reservoir development plan.
Based on the reservoir development stage and reservoir geological features, all related uncertainty factors are identified. And the uncertainty range of each factor are determined with upside, expected and downside values or models. Then all factors are embedded into the static and dynamic models, and the uncertainty impact on reservoir performance are quantitatively evaluated based on the upside, expected and downside dynamic models respectively. After that, uncertainty parameters are ranked into differernt groups.
Take one large multi-layered sandstone oilfield in Middle East for example, uncertainty analysis methods are illustrated. The large sandstone reservoir in Middle East is at its primary depletion development stage with only 5% recovery factor currently, and waterflooding is urgert. Firstly, key uncertainty parameters are determined, which can be mainly classified into two categoriesgeological model and dynamic model. Then according to the characteristic of this reservoir and uncertainties understanding of geological study, 3 static models with same probability are built. After that, uncertainties understanding of dynamic analysis are included into static models, and 3 dynamic models representing Upside, Expected and Downside models are generated in order to fully characterize all the uncertainties. So development options and development schemes optimization can be studied based on the 3 models in order to determine the uncertainties of water flooding performance. Finally the induced risks of each main uncertainty parameter are quantitatively evaluated, and corresponding treatments are proposed.
This paper offers the methodology and a case study on uncertainty analysis and management within the waterflooding development for a large multi-layered sandstone reservoir, and the results are valuable for the following development options decision making. It also provides a reference for uncertainty management of similar reservoir.
Reservoir Rock and Fluid Characterization Using Distributed Temperature Sensing DTS Systems Data
Authors: Xu Bohan , Forouzanfar Fahim 
Published: March 2017

Abstract
The variation of temperature profile of the sandface and wellbore offers important indicators for the occurrence of various downhole phenomena, as functions of reservoir formation and fluid properties. This paper aims to investigate the assimilation of temperature and production data for robust and efficient estimation of reservoir formation properties and fluid characterization. Very few previous work in the literature used Distributed Temperature Sensing (DTS) data for the characterization of the reservoir fluid and geostatistical description. The main contribution of this work lies in the proposed methodology for integration of temperature data from DTS systems to obtain a robust estimation of the reservoir fluid description, as well as introducing the integration of temperature data as an alternative and/or complementary data for integrative reservoir characterization. Two synthetic reservoir examples are investigated. In the first example, we focus on resolving the geostatistical description of a 3D multi-phase reservoir under water flooding. An ensemble-based data assimilation algorithm is used to compare the characterization of reservoir formation porosity and permeability by integration of temperature profile and well production data as opposed to the integration of production logging tool (PLT) data. Our results show that the DTS temperature data shows good potential as an alternative to the PLT data for reservoir rock characterization, although there may be a risk of model overfitting due to the large amount of data. In the second example, we attempt to estimate the original composition of the reservoir fluid as well as reservoir rock properties using downhole temperature profile data. A relatively simple multi-layer radial reservoir model is considered in this case. However, in order to honor the physical bounds on the various model parameters, a constrained ensemble-based data assimilation algorithm based on Lagrange multipliers is adopted. The computational results show that the original reservoir fluid composition could be excellently estimated for a case with known reservoir properties. Presence of uncertainty in the reservoir formation properties resulted in an poor estimation of the original reservoir fluid composition.
Methane Transport through Nanoporous Shale with Sub-Irreducible Water Saturation
Authors: Li Jing , Li Xiangfang , Wu Keliu , Chen Zhangxin John , Wang Kun , Zhong Minglu , Bai Zhijun 
Published: March 2017

Abstract
Characteristics of gas transport in nanopores are topics of great interest for evaluation of unconventional reservoirs. The apparent permeability model for single-phase gas flow has been extensively investigated. Few models, however, have been established for the gas transport in gas/liquid two-phase flow condition. Unfortunately, initial water always exists under reservoir condition. Although it is regarded as immobile state, the impact of which on gas flow capacity should not be simply neglected.
In this work, firstly, the state of sub-irreducible water saturation in unconventional reservoirs have been carefully investigated, and the thickness of thin film bound on inorganic pore surface (e.g. clay or quartz) has been quantified. Subsequently, by considering the impact of the water film on the effective hydraulic diameter, gas slip-flow model is established. Noting that the gas phase in moist conditions is mainly composed of both methane and vapor rather than single-component methane. Thus, the methane-vapor binary gas state equation has been introduced to describe the real gas effect under high pressure and temperature condition. Our proposed model has been directly verified by the laboratory tests, and the gas relative permeability in different cases with varying Knudsen numbers has been computed.
To our surprise, the calculated relative permeability curves for gas transport in narrow pores demonstrate as convex shape, which indicates that the influence of water on gas flow weakens as the increase of irreducible water saturation. This phenomenon become obvious especially in large Knudsen number condition. In fact, as the increase of Knudsen number, the gas slippage becomes significant and the relative impact of pre-adsorbed water reduces. For a typical tight gas reservoir with initial water saturation of 30%, the effective permeability for gas transport will reduce about 15%~30%, which depends on the Knudsen number for gas transport. Therefore, neglecting the effect of two-phase interaction might overestimate the gas deliverability.
Peningkatan kemampuan membaca permulaan melalui media video compact disc pada anak usia 5– 6 tahun
Authors: Sulistyawati Elisabeth Eka , Sujarwo Sujarwo 
Published: March 2017

Penelitian ini bertujuan untuk meningkatkan kemampuan membaca permulaan anak melalui media VCD di TK Kudup Sari Sidoluhur, Godean, Sleman. Kemampuan membaca pada anak terlihat dalam kemampuan menyebutkan simbol-simbol huruf vokal dan konsonan, menghubungkan gambar dengan kata, membaca gambar yang memiliki kata sederhana dan membaca nama sendiri.Penelitian ini adalah penelitian tindakan kelas kolaboratif yang menggunakan model Kemmis dan Mc Taggart. Penelitian ini terdiri dari dua siklus dan setiap siklus terdiri dari tiga pertemuan. Data diperoleh melalui observasi dan dokumentasi. Subjek pada penelitian ini adalah anak kelompok B TK Kudup Sari yang berjumlah 26 anak. Analisis data dilakukan secara deskriptif kualitatif.Kata kunci: kemampuan membaca permulaan, VCD, anak usia 5-6 tahun. Improvement of Early Reading Competence Using Video Compact Disc Media on 5-6 Year-Old AbstractThis research aims to improve early reading competence using VCD media on the pupils of TK Kudup Sari Sidoluhur, Godean, Sleman. The pupil reading competence can be shown by mentioning symbols of vocal and consonant letters, connecting pictures and words, reading pictures that have simple words and reading their own names.This is a collaborative classroom action research applying a model of Kemmis and Mc Taggart. It consists of two phases and each phase contains three meetings. Data were taken by observation and documentation. The subjects of the research are 26 pupils as the Group B of TK Kudup Sari. Analysing data was done using qualitative description. Keywords: early reading competence, VCD, 5-6-year-old pupils.
Implementasi model pembelajaran mandiri program pendidikan kecakapan hidup perempuan
Authors: Saripah Iip , Shantini Yanti 
Published: March 2017

Penelitian ini bertujuan untuk mengkaji implementasi model pembelajaran mandiri program pendidikan kecakapan hidup perempuan di PKBM Bina Cipta Ujungberung. Penelitian ini menggunakan pendekatan kualitatif deskriptif. Adapun lokasi penelitian dipilih dilaksanakan di PKBM Bina Cipta Ujungberung Kota Bandung. Hasil dari penelitian ini yaitu: (1) proses pembelajaran model pembelajaran mandiri pada program kecakapan hidup perempuan, meliputi kegiatan perencanaan mencakup kegiatan menentukan tujuan, menetukan instruktur, mengalokasikan waktu, merekrut peserta, menyusun kurikulum, menyusun materi, menentukan sumber belajar, menyiapkan saran dan prasarana, menyusun pembiayaan, kegiatan pelaksanaan mencakup kegiatan pengelolaan kelas dan peserta didik, pengelolaan instruktur, mennetukan metode dan media pembelajaran; kegiatan evaluasi mencakup evaluasi hasil belajar dan evaluasi proses pembelajaran. (2) penerapan model pembelajaran mandiri pada program kecakapan hidup perempuan, mencakup kegiatan pemberian motivasi, penyampian materi, pengaplikasian materi dan refleksi hasil belajar (3) hasil penerapan model pembelajaran mandiri pada program kecakapan hidup perempuan meliputi pengetahuan, afektif dan psikomotorik.Kata Kunci: model pembelajaran mandiri, pendidikan kecakapan hidup, PKBM. IMPLEMENTATION OF SELF DIRECTED LEARNING MODEL LIFE SKILLS EDUCATION PROGRAM WOMEN IN BINA CIPTA UJUNGBERUNG CLC AbstractThis study aims to assess about implementation of models of independent learning life skills education program in the CLC women Bina Cipta Ujungberung. This study used descriptive qualitative approach. The location of the research been conducted at CLC Bina Cipta Ujungberung Bandung, The results of this study are: (1 ) learning model of independent learning in life skills programs women, includes planning includes activities set goals, determine the instructor, allocate time, recruiting participants, develop curricula, organizing material, to determine the source of learning, to prepare suggestions and improvements, arrange financing, implementation activities include classroom management activities and learners, instructors management, menentukan methods and learning media; evaluation activities include evaluation of learning outcomes and learning process evaluation. (2) the application of self-learning model in female life skills programs, covers the activities of motivation, penyampaian material, the application of the material and reflection of learning outcomes (3) the results of the application of self-learning model in female life skills program include knowledge, affective and psychomotor.Keywords: learning model, life skills education, CLC
Morfología de Passiflora: una guía para la descripción de sus especies
Authors: Bonilla Morales Miguel Macgayver , Aguirre Morales Adriana Carolina , Agudelo Varela Oscar Manuel 
Published: March 2017

<p>Las pasifloras son un grupo de plantas que tienen uso desde periodos precolombinos por el sabor de sus frutos, sin embargo, en los últimos siglos<br />se han encontrado compuestos de importancia farmacéutica para la salud humana. Desde esta perspectiva, conocer las especies mediante sus caracteres morfológicos permitirá explorar la variabilidadexistente a nivel intra e inter especifico, y también definir a futuro su importancia económica<br />por su uso potencial. Por tal motivo, el objetivo de esta investigación fue definir e ilustrar los caracteres morfológicos más utilizados en Passiflora L. para estudios de diversidad, caracterización y taxonomía en Colombia. De esta manera, se establecieron los ítems de hábito, raíz, tallo, estípula,<br />hoja, flor, inflorescencia, fruto y semilla con sus respectivas descripciones que relacionan la taxonomía actual de Passiflora. Adicional, se añadió<br />un componente de polinización que determinó las principales relaciones florísticas y polinizadores como insectos, aves y mamíferos. Se concluye<br />que el entendimiento de las estructuras morfológicas en Passiflora servirá de guía para trabajos de caracterización de germoplasma y revisiones<br />taxonómicas como eje para describir nuevas especies. </p>
Modelación hidrodinámica y determinación de la calidad del agua en el río Botello, Facatativá, Cundinamarca, Colombia
Authors: Antonio Paiba Angel Oswaldo , Monroy Avila Edinson Fabian 
Published: March 2017

<p>La presente investigación plantea estudiar el comportamiento hidrodinámico de un tramo del Río Botello comprendido en la zona de influencia de la cabecera municipal de Facatativá, departamento de Cundinamarca, Colombia. En la primera fase, se determinaron las variables hidrodinámicas esenciales para realizar el modelamiento hidrodinámico, además, se determinaron las variables para estudiar la calidad del agua. Para la parte hidrodinámica, se recopiló información de velocidades, áreas transversales, y batimetría. Con respecto a la calidad, se determinaron temperatura, acidez, color, coliformes, sólidos disueltos, DBO5, DQO, nitratos, nitritos, manganeso y hierro. En la segunda fase, se procesó la información para finalmente generar el modelamiento hidrodinámico del río Botello. Se concluyó que la modelación del río Botello se constituye como una herramienta indispensable para la gestión integral del recurso hídrico en el municipio de Facatativá. En los puntos de muestreo hay razones de variación de las variables hidrodinámicas de acuerdo con el tramo analizado y de la calidad del agua, las cuales están fuertemente influenciadas por las actividades agropecuarias e industriales que se realizan en la zona circundante del sistema hídrico, lo cual acarrea grandes problemas de calidad a la oferta del recurso hídrico para los habitantes del municipio que suplen sus necesidades básicas del río Botello. En cuanto a inundaciones, se precisa que el municipio de Facatativá se encuentra en una zona de riesgo en períodos de alta precipitación.</p>