Experiments on surface deformation arising from a subsurface fracture

1995 ◽  
Vol 32 (6) ◽  
pp. 1024-1034 ◽  
Author(s):  
Gang Wang ◽  
Maurice B. Dusseault ◽  
Jerzy T. Pindera
Keyword(s):  
Large Scale ◽  
Surface Deformation ◽  
Scale Effects ◽  
Model Simulation ◽  
Laboratory Data ◽  
Nonlinear Problems ◽  
Laboratory Simulation ◽  
Scale Model ◽  
Laboratory Model ◽  
Hydraulic Fractures

Laboratory model simulation of large-scale earth processes is rarely undertaken because of scale effects, nonlinearity, and questions of representativeness with respect to the real case. Hydraulic fractures generate distortion fields that can be measured with high precision both in the laboratory and in the field. A combination of field and laboratory data allows us to test our ability to measure displacements, make forward predictions, and invert real measurements; thus it is important to have some means of simulation, other than purely numerical simulation. This paper contains the results of a set of experiments on the surface deformation arising from a pressurized fracture, using laser holography and Fizeau interferometry of noncontacting techniques to precisely sample the displacement field above a scale model. The results are remarkably accurate and consistent, and compare reasonably well with analytical and numerical model predictions. The techniques have potential applications in geomechanics and geotechnical engineering for laboratory study of various linear and nonlinear problems. Key words : laboratory simulation, holographic, Fizeau interferometry, hydrofractures.

Workflow for Oil Recovery Design by Polymer Flooding

2018 ◽  
Author(s):  
Vitor Hugo de Sousa Ferreira ◽  
Rosangela B. Z. L. Moreno
Keyword(s):  
Data Integration ◽  
Oil Recovery ◽  
History Matching ◽  
Large Scale ◽  
Laboratory Data ◽  
Polymer Flooding ◽  
Laboratory Simulation ◽  
Laboratory Model ◽  
Heavy Oils ◽  
Production Forecast

Polymer flooding dates from the 1960s. Early applications targeted onshore medium-to-heavy oils up to 100 cP, with limited reservoir temperature and water formation salinity. The number of implemented polymer flooding projects followed oil prices. Since its early days, polymer flooding had overcome many technical obstacles. Advances in polymer manufacturing technology, cost reduction and the use of horizontal wells have pushed polymer flooding as a feasible EOR method. A better understanding of the physical phenomena associated with polymer flow through porous media and technology advancement have extended polymer flooding applications to more viscous oil, higher salinity, and temperature level, as well as to offshore prospects. Meaningful advantages of polymer flooding over conventional methods are consolidated in the literature, such as oil recovery anticipation, incremental oil recovery and reduced volumes of injected and produced water to reach a target recovery factor. Despite all technological advances, polymer flooding needs to be tailored for the specific conditions of the target reservoir. Collect and integrate laboratory, simulation, and field information are essential for a successful polymer flooding application. This paper aims to correlate critical information to the various stages necessary for polymer flooding evaluation and production forecast. First, successfully implemented field cases allow the establishment of ranges for the method application. Once the applicability of polymer flooding is certified, the polymer solution to be injected is designed according to the reservoir characteristics and target conditions. Laboratory tests are performed to determine phase mobilities, polymer retention, and polymer degradation. These parameters are assessed through different experiments, and normalized variables provide data integration. Once the required parameters are determined, it is possible to build a base simulation model. History matching this base model to the laboratory data certifies its validity. An upsized analysis of this model is required to include some degradation phenomena. The 1D laboratory model is extended to a 3D model that incorporates permo-porosity distributions to analyze well characteristics in their radius of influence. The final step is large scale simulation and production forecast. Data integration along each stage and among then all allow the tailoring of the polymer flooding to EOR. The use of normalized parameters to evaluate the results is useful for analysis at different scales, from the laboratory to the reservoir. The proposed workflow can contribute to the design, planning, evaluation, and implementation of polymer flooding in a target field.

scholarly journals An adsorption theory of heterogeneous nucleation of water vapour on nanoparticles

2015 ◽  
Vol 15 (15) ◽  
pp. 21883-21906
Author(s):  
A. Laaksonen ◽  
J. Malila
Keyword(s):  
Water Vapour ◽  
Heterogeneous Nucleation ◽  
Large Scale ◽  
Laboratory Data ◽  
Theoretical Description ◽  
Nucleation Theory ◽  
Cloud Formation ◽  
Scale Model ◽  
Adsorption Theory ◽  
Ice Cloud

Abstract. Heterogeneous nucleation of water vapour on insoluble nuclei is a phenomenon that can induce atmospheric water and ice cloud formation. However, modelling of the phenomenon is hampered by the fact that the predictive capability of the classical heterogeneous nucleation theory is rather poor. A reliable theoretical description of the influence of different types of water-insoluble nuclei in triggering the water condensation or ice deposition would help to decrease uncertainty in large scale model simulations. In this paper we extend a recently formulated adsorption theory of heterogeneous nucleation to be applicable to highly curved surfaces, and test the theory against laboratory data for water vapour nucleation on silica, titanium dioxide and silver oxide nanoparticles. We show that unlike the classical heterogeneous nucleation theory, the new theory is able to quantitatively predict the experimental results.

scholarly journals An adsorption theory of heterogeneous nucleation of water vapour on nanoparticles

2016 ◽  
Vol 16 (1) ◽  
pp. 135-143 ◽  
Author(s):  
A. Laaksonen ◽  
J. Malila
Keyword(s):  
Water Vapour ◽  
Heterogeneous Nucleation ◽  
Large Scale ◽  
Laboratory Data ◽  
Theoretical Description ◽  
Nucleation Theory ◽  
Cloud Formation ◽  
Scale Model ◽  
Adsorption Theory ◽  
Ice Cloud

Abstract. Heterogeneous nucleation of water vapour on insoluble nuclei is a phenomenon that can induce atmospheric water and ice cloud formation. However, modelling of the phenomenon is hampered by the fact that the predictive capability of the classical heterogeneous nucleation theory is rather poor. A reliable theoretical description of the influence of different types of water-insoluble nuclei in triggering the water condensation or ice deposition would help to decrease uncertainty in large-scale model simulations. In this paper we extend a recently formulated adsorption theory of heterogeneous nucleation to be applicable to highly curved surfaces, and test the theory against laboratory data for water vapour nucleation on silica, titanium dioxide and silver oxide nanoparticles. We show that unlike the classical heterogeneous nucleation theory, the new theory is able to quantitatively predict the experimental results.

scholarly journals Micromechanical study of potential scale effects in small-scale modelling of sinker tree roots

2021 ◽  
Author(s):  
Xingyu Zhang ◽  
◽  
Matteo Ciantia ◽  
Jonathan Knappett ◽  
Anthony Leung ◽  
...  
Keyword(s):  
Particle Size ◽  
Large Scale ◽  
Scale Effects ◽  
Distinct Element ◽  
Scaling Law ◽  
Scale Model ◽  
Small Scale ◽  
Tree Roots ◽  
Scale Modelling ◽  
Element Method

When testing an 1:N geotechnical structure in the centrifuge, it is desirable to choose a large scale factor (N) that can fit the small-scale model in a model container and avoid unwanted boundary effects, however, this in turn may cause scale effects when the structure is overscaled. This is more significant when it comes to small-scale modelling of sinker root-soil interaction, where root-particle size ratio is much lower. In this study the Distinct Element Method (DEM) is used to investigate this problem. The sinker root of a model root system under axial loading was analysed, with both upward and downward behaviour compared with the Finite Element Method (FEM), where the soil is modelled as a continuum in which case particle-size effects are not taken into consideration. Based on the scaling law, with the same prototype scale and particle size distribution, different scale factors/g-levels were applied to quantify effects of the ratio of root diameter (𝑑𝑟) to mean particle size (𝐷50) on the root rootsoil interaction.

Creep Characteristics of Organic Soft Clay Soil Using Large–Scale Model

2021 ◽  
Author(s):  
Raid Al-Omari ◽  
◽  
Mohammed Fattah ◽  
Mudhafar Hameedi ◽  
◽  
...  
Keyword(s):  
Large Scale ◽  
Large Fraction ◽  
Soft Clay ◽  
Laboratory Data ◽  
Soil Surface ◽  
Organic Content ◽  
Scale Model ◽  
Secondary Compression ◽  
Large Scale Model

The long-term settlements in organic clay can create a kind of an engineering challenge that appear in most facilities design and construction in areas with deep deposits of soft clay. Peat ground is widely distributed throughout the southern part of Iraq. Peat contains a large amount of organic matter and has a very high natural water content. Three soil samples were collected from depths of 1.5 m, 2.5 m, and 3.5 m, below the soil surface in Halfaya oilfield, which lies east of Missan governorate southern Iraq. A series of tests were conducted in a large-scale model using a plate footing and considering three different percent of organic content. The percent of secondary settlement found is dependent on the stress level applied. A large fraction of the total settlement may be due to secondary compression. The assumption of a constant coefficient of secondary compression, Cα, may not be valid for a long-term settlement of peats. Laboratory data indicate that Cα generally increases with time. Thus, settlement predictions using constant Cα may underestimate field settlement.

scholarly journals Deflection characteristics of Unbound Base Course During a Large Scale Model Experiment

2015 ◽  
Vol 2 (1) ◽  
pp. 1
Author(s):  
Makhaly Ba ◽  
Meissa Fall ◽  
Oustasse Abdoulaye Sall
Keyword(s):  
Cyclic Loading ◽  
Model Experiment ◽  
Large Scale ◽  
Scale Effects ◽  
Base Layer ◽  
Scale Model ◽  
Pavement Materials ◽  
Elastic Deflection ◽  
Large Scale Model ◽  
Base Course

This paper evaluates de deflections (measured at the surface and/or at the top of the subgrade) of unbound pavement materials under cyclic loading. Deflections of three base course materials (Bakel Red Quartzite, Bakel Black Quartzite and Diack Basalt) were investigated using a large-scale model experiment (LSME). The LSME is a prototype-scale pavement test apparatus where cyclic loading is applied and deflections are measured. The LSME replicates field conditions and accounts for scale effects. The LSME results showed that the total, plastic and net plastic deflections of a pavement increase progressively as the number of loading cycles increases. The total deflection decreases as the thickness of the base layer increases. Plastics deflections at the top of the subgrade decrease progressively as the thickness of the base layer is increased. The elastic deflections of the surface and of the base layer decrease gradually with the increasing loading cycles. The elastic deflection at the top of the subgrade decreases with increasing thickness of the base layer. So, rutting can be limited by limiting the elastic deflection at the top of the subgrade. However, this criterion does not account for the rutting caused by the unbound base layers and that of the asphalt concrete.

scholarly journals Non-Repeatability, Scale- and Model Effects in Laboratory Measurement of Impact Loads Induced by an Overtopped Bore on a Dike Mounted Wall

2019 ◽  
Author(s):  
Maximilian Streicher ◽  
Andreas Kortenhaus ◽  
Corrado Altomare ◽  
Steven Hughes ◽  
Krasimir Marinov ◽  
...  
Keyword(s):  
Large Scale ◽  
Scale Effects ◽  
Vertical Wall ◽  
Scale Factor ◽  
Scale Model ◽  
Small Scale ◽  
Length Scale ◽  
Force Measurements ◽  
Impact Forces ◽  
Small Scale Model

Abstract Overtopping bore impact forces on a dike mounted vertical wall were measured in similar large-scale (Froude length scale factor 1-to-4.3) and small-scale (Froude length scale factor 1-to-25) models. The differences due to scale effects were studied, by comparing the up-scaled force measurements from both models in prototype. It was noted that if a minimum layer thickness, velocity of the overtopping flow and water depth at the dike toe were maintained in the small-scale model, the resulting differences in impact force due to scale effects are within the range of differences due to non-repeatability and model effects.

Scattering by hydraulic fractures: Finite‐difference modeling and laboratory data

Geophysics ◽  
2000 ◽  
Vol 65 (2) ◽  
pp. 612-622 ◽  
Author(s):  
Jeroen Groenenboom ◽  
Joachim Falk
Keyword(s):  
Finite Difference ◽  
Hydraulic Fracture ◽  
Large Scale ◽  
Seismic Waves ◽  
Laboratory Data ◽  
Small Scale ◽  
Hydraulic Fractures ◽  
Grid Spacing ◽  
Fine Grid ◽  
Arrival Times

Reservoir production can be stimulated by creating hydraulic fractures that effectively facilitate the inflow of hydrocarbons into a well. Considering the effectiveness and safety of the operation, it is desirable to monitor the size and location of the fracture. In this paper we investigate the possibilities of using seismic waves generated by active sources to characterize the fractures. First, we must understand the scattering of seismic waves by hydraulic fractures. For that purpose we use a finite‐difference modeling scheme. We argue that a mechanically open hydraulic fracture can be represented by a thin, fluid‐filled layer. The width or aperture of the fracture is often small compared to the seismic wavelength, which forces us to use a very fine grid spacing to define the fracture. Based on equidistant grids, this results in a large number of grid points and hence computationally expensive problems. We show that this problem can be overcome by allowing for a variation in grid spacing in the finite‐difference scheme to accommodate the large‐scale variation in such a model. Second, we show ultrasonic data of small‐scale hydraulic fracture experiments in the laboratory. At first sight it is difficult to unravel the interpretation of the various events measured. We use the results of the finite‐difference modeling to postulate various possible events that might be present in the data. By comparing the calculated arrival times of these events with the laboratory and finite‐difference data, we are able to propose a plausible explanation of the set of scattering events. Based on the laboratory data, we conclude that active seismic sources can potentially be used to determine fracture size and location in the field. The modeling example of fracture scattering illustrates the benefit of the finite‐difference technique with a variation in grid spacing for comparing numerical and physical experiments.

scholarly journals UNDISTORTED FROUDE MODEL FOR SURF ZONE SEDIMENT TRANSPORT

1986 ◽  
Vol 1 (20) ◽  
pp. 95 ◽  
Author(s):  
D.L. Kriebel ◽  
W.R. Dally ◽  
R.G. Dean
Keyword(s):  
Sediment Transport ◽  
Large Scale ◽  
Surf Zone ◽  
Scale Effects ◽  
Scale Model ◽  
Small Scale ◽  
Wave System ◽  
Governing Parameter ◽  
Fall Time ◽  
Offshore Transport

Small scale movable bed wave tank experiments were carried out according to undistorted Froude model laws with the sediment fall time, H/wT, as the governing parameter for scaling the model sediment. Four questions addressed in this study included: (a) the ability to reproduce larger scale model results for both erosional and accretive conditions, (b) the effects of more realistic concave upward initial beach profiles instead of the more usual planar initial slopes, (c) the criterion for onshore-offshore sediment transport, and (d) the capability of the model to simulate post-storm recovery. Based on a comparison with large scale results of Saville (1957), it was found that the model provided good agreement for erosive conditions. For accretive conditions, the results were less conclusive although the general patterns of profile change were similar. The final beach profiles resulting from concave upward initial profiles were found to be substantially different from those for an initially planar profile. It appears that the initially planar profile unrealistically affects the breaker type and results in a more pronounced longshore bar and offshore slopes that are steeper than found in nature. Tests conducted to evaluate the criterion separating onshore-offshore transport suggested a higher value of the fall time parameter, H/wT, than was originally proposed by Dean (1973); this is interpreted to be due to scale effects in most of the model data used in the original development. Tests to simulate post-storm recovery were affected by the presence of "reflection bars" associated with a partial standing wave system. The reflection bars appear to strongly affect the sediment transport limiting the post-storm profile recovery. The most effective recovery was induced by continually changing wave conditions to maintain the wave breakpoint slightly landward of the bar crest.

scholarly journals LARGE-SCALE AND SMALL-SCALE EFFECTS IN WAVE BREAKING INTERACTION ON VERTICAL WALL ATTACHED WITH LARGE RECURVE PARAPET

2020 ◽  
pp. 22
Author(s):  
Rajendran Ravindar ◽  
V Sriram ◽  
Stefan Schimmels ◽  
Dimitris Stagonas
Keyword(s):  
Wave Breaking ◽  
Large Scale ◽  
Impact Force ◽  
Scale Effects ◽  
Vertical Wall ◽  
Impact Pressure ◽  
Scale Model ◽  
Small Scale ◽  
Scaling Method ◽  
The Impact

Two sets of experiments on the vertical wall attached with recurve parapets performed at 1:1 and 1:8 scale are compared to study the influence of scale, model and laboratory effects. The small-scale (1:8) experiment scaled to large-scale (1:1) using Froude scaling, and Cuomo et al. (2010) method are compared. Comparing both the methods for scaling impact pressure, Cuomo et al. (2010) predicts well in the impact zone, whereas Froude scaling is better in the up-rushing zone. In estimating integrated impact force, Froude scaling method over-estimates compared to Cuomo et al. (2010). Overall, Cuomo et al. (2010) work better for scaling up impact pressure and forces compared to Froude scaling method. These preliminary observations are based on one type of recurved parapets only.Recorded Presentation from the vICCE (YouTube Link): https://youtu.be/w9WipBjMWzw

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