Influence of Oriented Perforation Design on Refracture Reorientation: Simulation and Experiment

2018 ◽  
Vol 140 (8) ◽  
Author(s):  
Minhui Qi ◽  
Mingzhong Li ◽  
Tiankui Guo ◽  
Chunting Liu ◽  
Song Gao ◽  
...  
Keyword(s):  
Hydraulic Fracturing ◽  
Large Scale ◽  
Simulation Models ◽  
Fracture Initiation ◽  
Simulation Method ◽  
Induced Stress ◽  
Study Results ◽  
Simulation Results ◽  
Fracturing Experiments ◽  
The Impact

The oriented perforating is the essential technique to guide the refracture reorientation, but the influence of the oriented perforation design on the refracture steering radius is still unclear. In this paper, the factors influencing the refracture reorientation were studied by simulation models and experiments. The effects of initial fracture, well production, and perforations on the refracture initiation and propagation were analyzed. Three-dimensional finite element models were conducted to quantify the impact of perforation depth, density, and azimuth on the refracture. The large-scale three-axis hydraulic fracturing experiments guided by oriented perforations were also carried out to verify the fracture initiation position and propagation pattern of the simulation results. The research results showed that perforations change the near-wellbore induced stress distribution, thus changing the steering radius of the refracture. According to the simulation results, the oriented perforation design has a significant influence on the perforation guidance effect and refracture characteristics. Five hydraulic fracturing experiments proved the influence of perforating parameters on fracture initiation and morphology, which have a right consistency between the simulation results. This paper presents a numerical simulation method for evaluating the influence of the refracture reorientation characteristics under the consideration of multiple prerefracturing induced-stress and put forward the oriented perforation field design suggestions according to the study results.

scholarly journals Experimental Study of Fracture Propagation: The Application in Energy Mining

Energies ◽  
2020 ◽  
Vol 13 (6) ◽  
pp. 1411 ◽  
Author(s):  
Yuxiang Cheng ◽  
Yanjun Zhang
Keyword(s):  
Hydraulic Fracturing ◽  
Large Scale ◽  
Production Efficiency ◽  
Fracture Initiation ◽  
Reservoir Simulations ◽  
Injection Flow ◽  
Complex Process ◽  
Injection Power ◽  
Fracturing Experiments ◽  
Rock Specimens

Hydraulic fracturing has been widely used in recent years as a key technology to improve energy mining efficiency in petroleum and geothermal industries. Laboratory hydraulic fracturing experiments recently were completed in six large-scale 300 × 300 × 300 mm rock specimens to better understand this complex process of hydraulic fracturing. When injection flow rate increases from 5 to 30 mL/min. The fracture initiation pressures and breakdown pressures increase, the propagation times and post-fracturing pressures decrease. The fracture geometries are observed and analyzed, mean injection power is proposed and results show that it could be used to roughly estimate the fracture total lengths. Moreover, the fracture permeabilities based on the pressure data are calculated and linearly ascend with the increase of injection flow rates. These results can provide some reasonable advice for implementing hydraulic fracturing reservoir simulations and improving energy production efficiency on application to field-scale operation.

scholarly journals Impact study of NOOR 1 project on the Moroccan territorial economic development

2021 ◽  
Vol 6 ◽  
pp. 8
Author(s):  
Amale Laaroussi ◽  
Abdelghrani Bouayad ◽  
Zakaria Lissaneddine ◽  
Lalla Amina Alaoui
Keyword(s):  
Economic Development ◽  
Renewable Energy ◽  
Economic Impact ◽  
Large Scale ◽  
Solar Power ◽  
Local Level ◽  
Concentrated Solar Power ◽  
Professional Literature ◽  
Study Results ◽  
The Impact

Morocco is one of the countries investing more and more in Renewable Energy (RE) technologies to meet the growing demand for energy and ensure the security of supply in this sector. The number of solar projects planned and implemented, as well as solar thermal projects in the form of Concentrating Solar Power (CSP) installations is steadily increasing. Many of these installations are designed as large utility systems. In order to provide strong evidence on local, regional and even national impacts, this article examines the impacts of large-scale renewable energy projects on territorial development, based on a case study of the NOOR 1 (Concentrated Solar Power (CSP)) project in Ouarzazate, Morocco. The data collected during this study, conducted through semi-structured interviews with experts, stakeholders, local community representatives and combined with an analysis of documents provided by the NOOR 1 project managers, investors and consulting firms specialized in the field of Renewable Energy, provide detailed evidence on the type and magnitude of impacts on the economic development of the Moroccan southern region where the NOOR 1 plant is located. The data collected is analyzed using NVIVO software. The study results in a consolidated list of many impacts with varying levels of significance for different stakeholder groups, including farmers, youth, women, community representatives and small and medium firms owners. It should be noted that the importance of analyzing the economic impact of large infrastructure projects is widely recognized, but so far, there is little published in the academic and professional literature on the potential impacts of these projects at the local level. Even less information is available on the local impacts of large-scale project implementation in Morocco. While many macroeconomic studies have fed the recent surge in investment in RE projects with the promise of multiple social, economic, environmental, and even geopolitical benefits at the macro level, public debates and discussions have raised considerable doubts. The question of whether these promises would also leave their marks at the local level has also arisen. Despite these uncertainties, very few academics and practitioners have conducted research to empirically develop a good understanding of the impact of RE projects at the local level. To fill this research gap, the economic impact analysis of NOOR 1 provides a detailed empirical overview, which allows a better understanding of the effects that the infrastructure developments of Concentrated Solar Power (CSP) plants can have on the economic environment in which they are located.

Behavior Selection Using Utility-Based Reinforcement Learning in Irregular Warfare Simulation Models

2013 ◽  
Vol 4 (3) ◽  
pp. 61-78 ◽  
Author(s):  
Sotiris Papadopoulos ◽  
Francisco Baez ◽  
Jonathan Alt ◽  
Christian Darken
Keyword(s):  
Reinforcement Learning ◽  
Adaptive Learning ◽  
Simulation Models ◽  
The Body ◽  
Irregular Warfare ◽  
Agent Based ◽  
Body Of Knowledge ◽  
Learning Techniques ◽  
Study Results ◽  
The Impact

The Theory of Planned Behavior (TPB) provides a conceptual model for use in assessing behavioral intentions of humans. Agent based social simulations seek to represent the behavior of individuals in societies in order to understand the impact of a variety of interventions on the population in a given area. Previous work has described the implementation of the TPB in agent based social simulation using Bayesian networks. This paper describes the implementation of the TPB using novel learning techniques related to reinforcement learning. This paper provides case study results from an agent based simulation for behavior related to commodity consumption. Initial results demonstrate behavior more closely related to observable human behavior. This work contributes to the body of knowledge on adaptive learning behavior in agent based simulations.

scholarly journals Impact Anlysis of Bow Flap on LHA-1 Ship Airwake

2018 ◽  
Vol 179 ◽  
pp. 03007
Author(s):  
Jinling Wang ◽  
Guangwen Jiang ◽  
Jun Shen ◽  
Chujun Hu
Keyword(s):  
Numerical Simulation ◽  
Simulation Method ◽  
Equation Model ◽  
Separation Region ◽  
Operating Environment ◽  
Study Results ◽  
Helicopter Landing ◽  
Hybrid Grid ◽  
Under Construction ◽  
The Impact

The sharp 90°corner of bow found on American Tarawa class general amphibious assault ship LHA-1 will produce large separated region in the airwake over the ship, and the turbulence in the separation region seriously affects the operation safety of the helicopter. In order to reduce the separation in bow region of the LHA-1, and optimize the helicopter operating environment, the numerical simulation method is used to study the influence of the bow flap on the airwake of LHA-1. The study results show that: the ANSYS k-ε two equation model based on the hybrid grid can be used to predict the steady-state characteristics of the ship airwake; the bow flap can improve the flow field downwind of the flap installation position, and the impact range can cover two spots; in headwind, the optimal installation angle of the bow flap is 15°~25°. The research results of this paper can provide modification and improvement reference for the amphibious assault ship in-service and under construction, so as to achieve the purpose of optimizing the ship airwake, thereby improving the safety of helicopter landing process and extending the service life.

scholarly journals Full-waveform-based characterization of acoustic emission activity in a mine-scale experiment: a comparison of conventional and advanced hydraulic fracturing schemes

2020 ◽  
Vol 222 (1) ◽  
pp. 189-206 ◽  
Author(s):  
Peter Niemz ◽  
Simone Cesca ◽  
Sebastian Heimann ◽  
Francesco Grigoli ◽  
Sebastian von Specht ◽  
...  
Keyword(s):  
Acoustic Emission ◽  
Hydraulic Fracturing ◽  
Induced Seismicity ◽  
Large Scale ◽  
Sampling Rate ◽  
Fracture Plane ◽  
B Values ◽  
Full Waveform ◽  
Scale Experiment ◽  
Fracturing Experiments

SUMMARY Understanding fracturing processes and the hydromechanical relation to induced seismicity is a key question for enhanced geothermal systems (EGS). Commonly massive fluid injection, predominately causing hydroshearing, are used in large-scale EGS but also hydraulic fracturing approaches were discussed. To evaluate the applicability of hydraulic fracturing techniques in EGS, six in situ, multistage hydraulic fracturing experiments with three different injection schemes were performed under controlled conditions in crystalline rock at the Äspö Hard Rock Laboratory (Sweden). During the experiments the near-field ground motion was continuously recorded by 11 piezoelectric borehole sensors with a sampling rate of 1 MHz. The sensor network covered a volume of 30×30×30 m around a horizontal, 28-m-long injection borehole at a depth of 410 m. To extract and characterize massive, induced, high-frequency acoustic emission (AE) activity from continuous recordings, a semi-automated workflow was developed relying on full waveform based detection, classification and location procedures. The approach extended the AE catalogue from 196 triggered events in previous studies to more than 19 600 located AEs. The enhanced catalogue, for the first time, allows a detailed analysis of induced seismicity during single hydraulic fracturing experiments, including the individual fracturing stages and the comparison between injection schemes. Beside the detailed study of the spatio-temporal patterns, event clusters and the growth of seismic clouds, we estimate relative magnitudes and b-values of AEs for conventional, cyclic progressive and dynamic pulse injection schemes, the latter two being fatigue hydraulic fracturing techniques. While the conventional fracturing leads to AE patterns clustered in planar regions, indicating the generation of a single main fracture plane, the cyclic progressive injection scheme results in a more diffuse, cloud-like AE distribution, indicating the activation of a more complex fracture network. For a given amount of hydraulic energy (pressure multiplied by injected volume) pumped into the system, the cyclic progressive scheme is characterized by a lower rate of seismicity, lower maximum magnitudes and significantly larger b-values, implying an increased number of small events relative to the large ones. To our knowledge, this is the first direct comparison of high resolution seismicity in a mine-scale experiment induced by different hydraulic fracturing schemes.

A Fundamental Study on Collision of a Tsunami Drifting Objects Against Structures Using MPS Method and FEM

2018 ◽  
Author(s):  
Koichi Masuda ◽  
Tomoki Ikoma ◽  
Daichi Murata ◽  
Hiroaki Eto ◽  
Akihiro Matsuoka ◽  
...  
Keyword(s):  
Finite Element ◽  
Large Scale ◽  
Steel Structure ◽  
Simulation Method ◽  
Coastal Areas ◽  
Numerical Calculations ◽  
Fundamental Study ◽  
Mps Method ◽  
Acrylic Plate ◽  
The Impact

The large-scale tsunami generated by the Great East Japan Earthquake on March 11, 2011 caused a great deal of damage. In addition to tsunami hydrodynamic forces, loads generated by drifting objects such as ships and cars can cause destruction in coastal areas. As such, impact forces due to collisions of drifting objects are an important consideration in the design and planning of structures in coastal areas. Depending on the size of the drifting object, it is difficult to evaluate the effect of the impact force at the time of collision through tank experiments. Therefore, it is necessary to develop a numerical simulation method that can reasonably evaluate such effects. Such a method must consider the nonlinear interactions among drifting objects, a fluid, and fixed structures. In the present study, we used the moving particle semi-implicit (MPS) and finite element methods to calculate the effect of collisions between drifting objects and structures, and then verified the results experimentally. The MPS method was applied to calculate the loads and pressures due to the collisions. These results were then used to simulate the deformation of the structure using the finite element method. A tank experiment was then conducted in order to confirm the accuracy of the numerical calculations. The deformation of a rod-shaped steel structure was measured following collision with a floating acrylic plate. The experimental results confirmed the accuracy of the numerical calculations.

scholarly journals Study on Fluorine Pollution in a Slag Yard

2019 ◽  
Vol 9 (5) ◽  
pp. 847
Author(s):  
Lide Wei ◽  
Changfu Wei ◽  
Sugang Sui
Keyword(s):  
Numerical Simulation ◽  
Experimental Investigation ◽  
Numerical Simulations ◽  
Solute Transport ◽  
Large Scale ◽  
Three Dimensional ◽  
Simulation Method ◽  
Laboratory Studies ◽  
Survey Results ◽  
Simulation Results

This paper suggests a large-scale three-dimensional numerical simulation method to investigate the fluorine pollution near a slag yard. The large-scale three-dimensional numerical simulation method included an experimental investigation, laboratory studies of solute transport during absorption of water by soil, and large-scale three-dimensional numerical simulations of solute transport. The experimental results showed that the concentrations of fluorine from smelting slag and construction waste soil were well over the discharge limit of 0.1 kg/m3 recommended by Chinese guidelines. The key parameters of the materials used for large-scale three-dimensional numerical simulations were determined based on an experimental investigation, laboratory studies, and soil saturation of survey results and back analyses. A large-scale three-dimensional numerical simulation of solute transport was performed, and its results were compared to the experiment results. The simulation results showed that the clay near the slag had a high saturation of approximately 0.9, consistent with the survey results. Comparison of the results showed that the results of the numerical simulation of solute transport and the test results were nearly identical, and that the numerical simulation results could be used as the basis for groundwater environmental evaluation.

Nano-Indentation Simulation Study Based on Parallel Computing

2012 ◽  
Vol 500 ◽  
pp. 696-701
Author(s):  
Ying Zhu ◽  
Sen Song ◽  
Ling Ling Xie ◽  
Shun He Qi ◽  
Qian Qian Liu
Keyword(s):  
Molecular Dynamics ◽  
Parallel Computing ◽  
Molecular Dynamics Simulation ◽  
Large Scale ◽  
Dynamics Simulation ◽  
Parallel Computer ◽  
Nano Indentation ◽  
Simulation Results ◽  
The Impact ◽  
Simulation Time

This method of parallel computing into nanoindentation molecular dynamics simulation (MDS), the author uses a nine-node parallel computer and takes the single crystal aluminum as the experimental example, to implement the large-scale process simulation of nanoindentation. Compared the simulation results with experimental results is to verify the reliability of the simulation. The method improves the computational efficiency and shortens the simulation time and the expansion of scale simulation can significantly reduce the impact of boundary conditions, effectively improve the accuracy of the molecular dynamics simulation of nanoindentation.

Numerical Simulation and Laboratory Experiments of Hydraulic Fracturing of Highly Deviated Well

2013 ◽  
Vol 275-277 ◽  
pp. 278-281 ◽  
Author(s):  
Hai Yan Zhu ◽  
Jing Gen Deng ◽  
Song Yang Li ◽  
Zi Jian Chen ◽  
Wei Yan ◽  
...  
Keyword(s):  
Numerical Simulation ◽  
Hydraulic Fracturing ◽  
Fracture Initiation ◽  
Element Model ◽  
Simulation Method ◽  
Horizontal Stress ◽  
Initiation Point ◽  
Strength Failure ◽  
Fluid Penetration ◽  
Maximum Horizontal Stress

Considering the combined action of the fluid penetration and the casing, the seepage coupled deformation finite element model of the highly deviated casing perforation well is established by using the tensile strength failure criterion and applied on the BZ25-1 oil filed. The results show that the increasing of the perforation angle and the well azimuth and the decreasing of the inclination would lead to a higher fracture initiation pressure. The fracture initiation point always locates on the wellbore face when the influence of the casing is considered. When the casing is ignored: when the perforation angle is 0°-45°, the fracture initiation point locates on the root of the tunnel; when the angle is 45°-90°, the fracture initiation point may be on the wellbore face or the perforation biased toward the maximum horizontal stress direction; when the angle is near to 90°, the hydraulic fracturing difficultly fractures the rock through the perforation tunnels. The laboratory hydraulic fracturing simulation experiments of 45° deviated well are carried through 400mm3 cement specimen so as to obtain the fracture initiation point and geometric shape under different perforation angles, the results verify the accuracy of the numerical simulation method.

Study of Sub-Synchronous Control Interaction (SSCI) Based on the Test Signal Method

2014 ◽  
Vol 989-994 ◽  
pp. 2980-2984
Author(s):  
Ben Feng Gao ◽  
Jin Liu ◽  
Shu Qiang Zhao
Keyword(s):  
Transmission Lines ◽  
Large Scale ◽  
Simulation Method ◽  
Test Signal ◽  
Equivalent Model ◽  
Series Compensation ◽  
Synchronous Control ◽  
The Impact ◽  
Signal Method ◽  
Control Interaction

Large-scale wind turbine generators with power electronic converters that operate near series compensated transmission lines are susceptible to un-damped sub-synchronous oscillations. This sub-synchronous oscillation is called Sub-synchronous Control Interaction (SSCI). Based on PSCAD / EMTDC simulation platform the establishment of Double Fed Induction Generator (DFIG) equivalent inverter controlled sources and network model, and verify the correctness of the equivalent model. Analysis the impact of series compensation and rotor-side converter PI parameters characteristic of the SSCI based on test signal method and time-domain simulation method. The results show that increasing the degree of series compensation , inner gain constant increases and inner integral time decreases will help increase SSCI, outer ring of PI parameters has little effect on the SSCI .

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