scholarly journals Research on small-scale sand fracturing and puff technology

2021 ◽  
Vol 329 ◽  
pp. 01001
Author(s):  
Qian Wang ◽  
Zuohao Wu ◽  
Jiapeng Zheng ◽  
Junkai Lu ◽  
Menghong Yu

Affected by complex fault blocks, sedimentary environment and reservoir physical properties, Jidong Oilfield generally develops small-scale sand bodies, accounting for 24.2% of the produced reserves of medium and low permeability reservoirs. Such sand bodies rely on elastic energy to develop and are difficult to use effectively. In this paper, through the three-dimensional hydraulic physical model experiment and the analysis of the oil layer-dry layer-mudstone mixed sand body, the reasons that affect the model parameters are obtained. The results show that: the length of the high-permeability reservoir area, the length of the intermediate-permeability dry layer area, the rate of change of permeability parameters, the viscosity of the construction fluid, and the construction displacement have an impact on the effect of fracturing enhanced injection energy storage.

2021 ◽  
pp. 014459872199560
Author(s):  
Zhaosheng Wang ◽  
Lianbo Zeng ◽  
Jiangtao Yu ◽  
Zhenguo Zhang ◽  
Siyu Yang ◽  
...  

Carbon dioxide (CO2) flooding is an effective method to enhance oil recovery in low-permeability reservoirs. Studying key geological factors controlling oil displacement efficiency is of great significance to the CO2 injection scheme design in low-permeability reservoirs. Focusing on low-permeable H reservoir in Songliao Basin, China, this paper describes the contact and connection of sand bodies, natural fractures and high-permeability zones with core samples, log data and experiment firstly. After that, the impact of interaction of sand body connection, natural fracture and high-permeability zone on oil displacement efficiency is determined by using geological and dynamic data in CO2 injection area. Results indicate that the connection of single sand bodies between injectors and producters wells primarily controls CO2 flooding in low-permeability reservoirs. Furthermore, coupling of sand body connection, natural fractures and high-permeability zones is the key geological factor governing oil displacement efficiency of CO2 injection in low-permeability reservoirs, where well or generally-connected sand bodies can improve the efficiency significantly. Meanwhile, the dominant seepage channels in other directions have no influence on producers, which is beneficial to improve CO2 flooding efficiency.


2021 ◽  
pp. 1-36
Author(s):  
Zhangqing Sun ◽  
Xingguo Huang ◽  
Hongliang Li ◽  
Anguai Lei ◽  
Nuno Vieira da Silva ◽  
...  

The current energetic transition policies reenabled the importance of producing nuclear energy in producing electricity. Uranium is the principal fuel used in nuclear power plants, and mineral deposits containing this element are of strategic importance. The successful development of sandstone uranium deposits benefits from three-dimensional (3D) geophysical characterization of sand bodies in uranium reservoir. To solve this problem, a method based on 3D geostatistical resistivity inversion is adopted. Firstly, we analyze the application of that method to the problem in hand and introduce a workflow for analyzing the data. Secondly, through petro-physical sensitivity analysis, we identify the logging parameters that can characterize sandstone in this context, and we use that as the parameter estimated by the geostatistical inversion outlined herein. Then, the 3D data of inversion representing the sandstone of uranium reservoir is obtained by the 3D geostatistical resistivity inversion, demonstrating an accuracy well within an acceptable level of accuracy. Finally, the 3D data of inversion is applied to 3D spatial characterization of a sand body in uranium reservoir inverting a field dataset. Our method is useful in determining the location of drilling wells for exploration and development of sandstone uranium deposits.


2013 ◽  
Vol 731 ◽  
pp. 95-116 ◽  
Author(s):  
Marc Wolf ◽  
M. Holzner ◽  
B. Lüthi ◽  
D. Krug ◽  
W. Kinzelbach ◽  
...  

AbstractWe report on effects of mean shear on the turbulent entrainment process, focusing in particular on their relation to small-scale processes in the proximity of the turbulent/non-turbulent interface (TNTI). Three-dimensional particle tracking velocimetry (3D-PTV) measurements of an axisymmetric jet are compared to data from a direct numerical simulation (DNS) of a zero-mean-shear (ZMS) flow. First, conditional statistics relative to the interface position are investigated in a pseudo-Eulerian view (i.e. in a fixed frame relative to the interface position) and in a Lagrangian view. We find that in a pseudo-Eulerian frame of reference, both vorticity fluctuations and mean shear contribute to the vorticity jump at the boundary between irrotational and turbulent regions. In contrast, the Lagrangian evolution of enstrophy along trajectories crossing the entrainment interface is almost exclusively dominated by vorticity fluctuations, at least during the first Kolmogorov time scales after passing the interface. A mapping between distance to the instantaneous interface versus conditional time along the trajectory shows that entraining particles remain initially close to the TNTI and therefore attain lower average enstrophy values. The ratio between the rate of change of enstrophy in the two frames of references defines the local entrainment velocity ${v}_{n} = - (\mathrm{D} {\omega }^{2} / \mathrm{D} t)/ (\partial {\omega }^{2} / \partial {\hat {x} }_{n} )$, where ${\omega }^{2} $ is enstrophy and ${\hat {x} }_{n} $ is the coordinate normal to the TNTI. The quantity ${v}_{n} $ is decomposed into mean and fluctuating components and it is found that mean shear enhances the local entrainment velocity via inviscid and viscous effects. Further, the analysis substantiates that for all investigated flow configurations the local entrainment velocity depends considerably on the geometrical shape of the interface. Depending on the surface shape, different small-scale mechanisms are dominant for the local entrainment process, i.e. viscous effects for convex shapes and vortex stretching for concave shapes, looking from the turbulent region towards the convoluted boundary. Moreover, turbulent fluctuations display a stronger dependence on the shape of the interface than mean shear effects.


1992 ◽  
Vol 156 ◽  
pp. 41-46
Author(s):  
T Olsen

Upper Cretaceous deltaic sediments from the Atane Formation are well exposed in a series of steep-sided gullies at Paatuut on the south coast of Nuussuaq. The large exposures within the gullies allowed a large-scale sedimentological investigation of delta stratigraphy, sand-body geometry and fluvial style of the distributary channels. Multi-model photogrammetry was applied in several ways. Photogrammetric mapping of good exposures within the area produced accurate vertical sections up to 2 km long and 0.5 km high. A bed to bed stratigraphy of the delta cycles was established and the sand-bodies within each cycle correlated. The horizontal extent of the sand-bodies was subsequently mapped photogrammetrically using the already orientated stereomodels. This mapping allowed a three-dimensional interpretation of the sand-body geometry. Cross-sections of the sand-bodies and the sand-body geometry formed the basis for the interpretation of the fluvial style of the distributary channels. Using the three-dimensional photogrammetric data the width/thickness ratio, the sinuosity and the shape of sand-bodies as well as of palaeochannels are described. These data are useful when modelling the reservoir geometry in deltaic hydrocarbon fields.


2013 ◽  
Vol 868 ◽  
pp. 164-167
Author(s):  
Yong Qing Zhang ◽  
Shi Zhong Ma ◽  
Yu Sun ◽  
Jin Yan Zhang

Based on 22 well cores and logging data of nearly 800 well, sedimentary characteristics of Fuyu oil layer in the southern Fuxin uplift was analyzed. It is shown that types of sandstone in the Fuyu oil layer are main feldspathic litharenite, debris arkose and minor litharenite. Granularity probability curve is displayed as a typical of two-stage or three-stage. A large number of parallel bedding, one-way oblique bedding, small-scale cross bedding, the bottom scour structure and syngenetic deformation structure can be seen in the Fuyu oil layer. Mudstone color is main fuchsia, grey purple massive mudstone and gray-green, gray, dark gray massive mudstone. Combined with the analysis of the sedimentary facies sign, Fuyu oil layer in the southern Fuxin uplift is large fluvial-dominated shallow water delta deposition. The skeletal sand bodies in the delta system are distributary channelsand bodies that are large, dense, narrow strip, continuous distribution. The overall is south-southwest trending. Sand body is continuous and far underwater extension until it disappears into thin sandsheet. multi-branch fluvial-dominated ribbon-like bodies are formed.


Geology ◽  
2020 ◽  
Vol 48 (9) ◽  
pp. 903-907
Author(s):  
Hiranya Sahoo ◽  
M. Royhan Gani ◽  
Nahid D. Gani ◽  
Gary J. Hampson ◽  
John A. Howell ◽  
...  

Abstract Despite the importance of channel avulsion in constructing fluvial stratigraphy, it is unclear how contrasting avulsion processes are reflected in stratigraphic-stacking patterns of channelized fluvial sand bodies, as a proxy for how river depocenters shifted in time and space. Using an integrated, geospatially referenced, three-dimensional data set that includes outcrop, core, and lidar data, we identify, for the first time in an outcrop study, a predictive relationship between channelized sand body architecture, paleochannel mobility, and stratigraphic-stacking pattern. Single-story sand bodies tend to occur in vertically stacked clusters that are capped by a multilateral sand body, indicating an upward change from a fixed-channel system to a mobile-channel system in each cluster. Vertical sand body stacking in the clusters implies reoccupation of abandoned channels after “local” avulsion. Reoccupational avulsion may reflect channel confinement, location downstream of a nodal avulsion point that maintained its position during development of the sand body cluster, and/or aggradation and progradation of a backwater-mediated channel downstream of a nodal avulsion point. Sand body clusters and additional multilateral sand bodies are laterally offset or isolated from each other, implying compensational stacking due to “regional” switching of a nodal avulsion point to a new, topographically lower site on the floodplain. The predictive links between avulsion mechanisms, channel mobility, and resultant sand body distributions and stacking patterns shown in our findings have important implications for exploring and interpreting spatiotemporal patterns of stratigraphic organization in alluvial basins.


2019 ◽  
Vol 24 (42) ◽  
pp. 4991-5008 ◽  
Author(s):  
Mohammed S. Algahtani ◽  
Abdul Aleem Mohammed ◽  
Javed Ahmad

Three-dimensional printing (3DP) has a significant impact on organ transplant, cosmetic surgery, surgical planning, prosthetics and other medical fields. Recently, 3 DP attracted the attention as a promising method for the production of small-scale drug production. The knowledge expansion about the population differences in metabolism and genetics grows the need for personalised medicine substantially. In personalised medicine, the patient receives a tailored dose and the release profile is based on his pharmacokinetics data. 3 DP is expected to be one of the leading solutions for the personalisation of the drug dispensing. This technology can fabricate a drug-device with complicated geometries and fillings to obtain the needed drug release profile. The extrusionbased 3 DP is the most explored method for investigating the feasibility of the technology to produce a novel dosage form with properties that are difficult to achieve using the conventional industrial methods. Extrusionbased 3 DP is divided into two techniques, the semi-solid extrusion (SSE) and the fused deposition modeling (FDM). This review aims to explain the extrusion principles behind the two techniques and discuss their capabilities to fabricate novel dosage forms. The advantages and limitations observed through the application of SSE and FDM for fabrication of drug dosage forms were discussed in this review. Further exploration and development are required to implement this technology in the healthcare frontline for more effective and personalised treatment.


Hydrology ◽  
2021 ◽  
Vol 8 (3) ◽  
pp. 102
Author(s):  
Frauke Kachholz ◽  
Jens Tränckner

Land use changes influence the water balance and often increase surface runoff. The resulting impacts on river flow, water level, and flood should be identified beforehand in the phase of spatial planning. In two consecutive papers, we develop a model-based decision support system for quantifying the hydrological and stream hydraulic impacts of land use changes. Part 1 presents the semi-automatic set-up of physically based hydrological and hydraulic models on the basis of geodata analysis for the current state. Appropriate hydrological model parameters for ungauged catchments are derived by a transfer from a calibrated model. In the regarded lowland river basins, parameters of surface and groundwater inflow turned out to be particularly important. While the calibration delivers very good to good model results for flow (Evol =2.4%, R = 0.84, NSE = 0.84), the model performance is good to satisfactory (Evol = −9.6%, R = 0.88, NSE = 0.59) in a different river system parametrized with the transfer procedure. After transferring the concept to a larger area with various small rivers, the current state is analyzed by running simulations based on statistical rainfall scenarios. Results include watercourse section-specific capacities and excess volumes in case of flooding. The developed approach can relatively quickly generate physically reliable and spatially high-resolution results. Part 2 builds on the data generated in part 1 and presents the subsequent approach to assess hydrologic/hydrodynamic impacts of potential land use changes.


2021 ◽  
Vol 9 (6) ◽  
pp. 585
Author(s):  
Minghao Wu ◽  
Leen De Vos ◽  
Carlos Emilio Arboleda Chavez ◽  
Vasiliki Stratigaki ◽  
Maximilian Streicher ◽  
...  

The present work introduces an analysis of the measurement and model effects that exist in monopile scour protection experiments with repeated small scale tests. The damage erosion is calculated using the three dimensional global damage number S3D and subarea damage number S3D,i. Results show that the standard deviation of the global damage number σ(S3D)=0.257 and is approximately 20% of the mean S3D, and the standard deviation of the subarea damage number σ(S3D,i)=0.42 which can be up to 33% of the mean S3D. The irreproducible maximum wave height, chaotic flow field and non-repeatable armour layer construction are regarded as the main reasons for the occurrence of strong model effects. The measurement effects are limited to σ(S3D)=0.039 and σ(S3D,i)=0.083, which are minor compared to the model effects.


Author(s):  
Christopher J. Arthurs ◽  
Nan Xiao ◽  
Philippe Moireau ◽  
Tobias Schaeffter ◽  
C. Alberto Figueroa

AbstractA major challenge in constructing three dimensional patient specific hemodynamic models is the calibration of model parameters to match patient data on flow, pressure, wall motion, etc. acquired in the clinic. Current workflows are manual and time-consuming. This work presents a flexible computational framework for model parameter estimation in cardiovascular flows that relies on the following fundamental contributions. (i) A Reduced-Order Unscented Kalman Filter (ROUKF) model for data assimilation for wall material and simple lumped parameter network (LPN) boundary condition model parameters. (ii) A constrained least squares augmentation (ROUKF-CLS) for more complex LPNs. (iii) A “Netlist” implementation, supporting easy filtering of parameters in such complex LPNs. The ROUKF algorithm is demonstrated using non-invasive patient-specific data on anatomy, flow and pressure from a healthy volunteer. The ROUKF-CLS algorithm is demonstrated using synthetic data on a coronary LPN. The methods described in this paper have been implemented as part of the CRIMSON hemodynamics software package.


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