scholarly journals Experimental Study of the Use of Tracing Particles for Interface Tracking in Primary Cementing in an Eccentric Hele–Shaw Cell

Energies ◽  
2021 ◽  
Vol 14 (7) ◽  
pp. 1884
Author(s):  
Amir Taheri ◽  
Jan David Ytrehus ◽  
Bjørnar Lund ◽  
Malin Torsæter
Keyword(s):  
Co2 Storage ◽  
Real Field ◽  
Interface Tracking ◽  
Vertical Flow ◽  
Pressure Gradients ◽  
High Quality ◽  
Neutral Buoyancy ◽  
Primary Cementing ◽  
Fluid Rheology ◽  
Hele Shaw Cell

We present the results of the displacement flows of different Newtonian and Herschel–Bulkley non-Newtonian fluids in a new-developed eccentric Hele–Shaw cell with dynamic similarly to real field wellbore annulus during primary cementing. The possibility of tracking the interface between the fluids using particles with intermediate or neutral buoyancy is studied. The behaviors and movements of particles with different sizes and densities against the primary vertical flow and strong secondary azimuthal flow in the eccentric Hele–Shaw cell are investigated. The effects of fluid rheology and pumping flow rate on the efficiency of displacement and tracing particles are examined. Moreover, the behavior of pressure gradients in the cell is described and analyzed. Successful results of tracing the interface using particles give us this opportunity to carry out a primary cementing with high quality for the cases that the risk of leakage is high, e.g., primary cementing in wells penetrating a CO2 storage reservoir.

scholarly journals Use of Concentric Hele-Shaw Cell for the Study of Displacement Flow and Interface Tracking in Primary Cementing

Energies ◽  
2020 ◽  
Vol 14 (1) ◽  
pp. 51
Author(s):  
Amir Taheri ◽  
Jan David Ytrehus ◽  
Bjørnar Lund ◽  
Malin Torsæter
Keyword(s):  
Yield Stress ◽  
Drilling Fluid ◽  
Co2 Storage ◽  
Main Idea ◽  
Real Field ◽  
Interface Tracking ◽  
Pressure Gradients ◽  
Cell Geometry ◽  
Primary Cementing ◽  
Hele Shaw Cell

We present our new designed concentric Hele-Shaw cell geometry with dynamic similarity to a real field wellbore annulus during primary cementing, and then, the results of displacement flow of Newtonian and yield-stress non-Newtonian fluids in it are described. The displacement stability and efficiency, the effect of back, front, and side boundaries on displacement, bypassing pockets of displaced yield-stress fluid in displacing fluid, and the behavior of pressure gradients in the cell are investigated. Applications of intermediate buoyant particles with different sizes and densities intermediate between those of successively pumped fluids for tracking the interface between the two displaced and displacing fluids are examined. The main idea is to upgrade this concentric Hele-Shaw cell geometry later to an eccentric one and check the possibility of tracking the interface between successive fluids pumped in the cell. Successful results help us track the interface between drilling fluid and spacer/cement during primary cementing in wells penetrating a CO2 storage reservoir and decreasing the risk of CO2 leakage from them.

High quality SWCNT synthesis in the presence of NH3 using a vertical flow aerosol reactor

2009 ◽  
Vol 246 (11-12) ◽  
pp. 2507-2510 ◽  
Author(s):  
Toma Susi ◽  
Albert G. Nasibulin ◽  
Paola Ayala ◽  
Ying Tian ◽  
Zhen Zhu ◽  
...  
Keyword(s):  
Vertical Flow ◽  
High Quality

Pressure Drop During Condensation in Microchannels

2013 ◽  
Vol 135 (9) ◽  
Author(s):  
Hua Sheng Wang ◽  
Jie Sun ◽  
John W. Rose
Keyword(s):  
Experimental Data ◽  
Pressure Gradient ◽  
Void Fraction ◽  
Annular Flow ◽  
Gradient Methods ◽  
Pressure Gradients ◽  
High Quality ◽  
Friction Pressure ◽  
Flow Condensation ◽  
Approximate Equations

The paper reports calculations of friction pressure gradient for the special case of laminar annular flow condensation in microchannels. This is the only flow regime permitting theoretical solution without having recourse to experimental data. Comparisons are made with correlations based on experimental data for R134a. The correlations differ somewhat among themselves with the ratio of highest to lowest predicted friction pressure gradient typically around 1.4 and nearer to unity at high quality. The friction pressure gradients given by the laminar annular flow solutions are in fair agreement with the correlations at high quality and lower than the correlations at lower quality. Attention is drawn to the fact that the friction pressure gradient cannot be directly observed and its evaluation from measurements requires estimation of the nondissipative momentum or acceleration pressure gradient. Methods used to estimate the nondissipative pressure gradient require quality and void fraction together with equations which relate these and whose accuracy is difficult to quantify. Quality and void fraction can be readily found from the laminar annular flow solutions. Significant differences are found between these and values from approximate equations.

Accuracy in estimating basal areas for forest inventories: comparison of Android-based virtual relascope and Spiegel Relaskop

2021 ◽  
Vol 51 (1) ◽  
pp. 132-137 ◽  
Author(s):  
Mònica Aguilera ◽  
Antonio Villasante ◽  
Cristina Fernandez
Keyword(s):  
Forest Inventory ◽  
Low Cost ◽  
Field Conditions ◽  
Real Field ◽  
High Quality ◽  
Forest Inventories ◽  
Low Performance ◽  
Counting Trees ◽  
Quality Measurements

The potential for using smartphones extends to forest inventory. Several applications allow the estimation of basal areas, transforming the device into a low-cost virtual relascope. The accuracy of the Bitterlich relascope application was analyzed using four low-performance devices. The results were compared with those of a Spiegel Relaskop. The measurements were taken with artificial targets; this increased the discrimination of the results in comparison with tests made by counting trees. To check the accuracy in real field conditions, the Bitterlich relascope application was compared with a Spiegel Relaskop. No significant differences in accuracy were found between the data obtained by the traditional relascope and that obtained by the Android devices, neither for the artificial target nor in field conditions. The obtained biases were also similar between the Spiegel Relaskop and the devices tested. To achieve high-quality measurements with the smartphones, a realistic calibration resembling forest inventory is needed.

scholarly journals Ways to increase soil fertility

2019 ◽  
pp. 23-34
Author(s):  
Yu Vozhik
Keyword(s):  
Organic Matter ◽  
Soil Fertility ◽  
Animal Husbandry ◽  
Organic Fertilizers ◽  
Real Field ◽  
Plant Residues ◽  
High Quality ◽  
Agricultural Producers ◽  
Natural Means ◽  
Practical Recommendations

Purpose. Improve soil fertility Ukraine. Methods. The scientific and practical concepts of the use of natural means for the industrial production of cheap organic fertilizers in real field conditions are used in the work. Results. By analyzing the results of scientific research and practical recommendations of agricultural producers, the real ways are recommendations are made for obtaining high quality organic fertilizers using inexpensive and natural ingredients. Conclusions. It is established that the deficit of organic matter in the soils of Ukraine, which was created due to landslide reduction of animal husbandry and natural manure, is quite realistically compensated by the use, of cheap natural materials such as peat, sapropels, siderates and vegetable residues, composting them in a stationary environment. with the use of microbiological preparations. The features of the technology of their use are identified and the necessary technical means. Keywords: organic fertilizers, peat, sapropels, siderates, plant residues, microbiological preparations, composts.

New Hybrid Hole Cleaning Model for Vertical and Deviated Wells

2019 ◽  
Vol 142 (3) ◽  
Author(s):  
Ahmed Abdulhamid Mahmoud ◽  
Mahmoud Elzenary ◽  
Salaheldin Elkatatny
Keyword(s):  
Drilling Fluid ◽  
Drill Pipe ◽  
Real Field ◽  
Oil Well ◽  
Hole Size ◽  
Drilling Mud ◽  
Rate Of Penetration ◽  
Hole Cleaning ◽  
Fluid Rheology ◽  
Pipe Size

Abstract Drilled cuttings transportation from the bottom hole to the surface to maintain efficient hole cleaning is a challenging issue while drilling vertical, deviated, high angle, and extended reach wells. This is attributed to the huge number of the parameters affecting the ability of the drilling fluid to leave the drilled solids. Drilling fluid rheology, density, and flowrate, hole size, drill pipe size, hole inclination, and rate of penetration are all confirmed experimentally to affect the effectiveness of the drilling mud to lift the fluid and keep a clean hole. Several parameters were developed earlier to account for the hole cleaning conditions, most of these parameters lake to including many of the parameters influencing the hole cleaning conditions. In this study, a new hole cleaning parameter was developed, which is called hole cleaning factor (HCF). The HCF parameter was developed based on the cutting carrying index (CCI) parameter, and it considered the effect of the drilling fluid rheology, density, and flowrate, the hole size, drill pipe size, hole inclination, and rate of penetration to identify the hole cleaning condition. The HCF model was applied in an oil well from North Africa to predict the hole cleaning condition at different 135 points where the depth ranges from 33 to 12,854 ft. The outcomes of the HCF were well correlated with the real-field scenarios, where the crew members faced by erratic torque with differentiation in drilling parameters resulting in worst stuck pipe conditions at the same depths as predicted by the HCF parameter. The developed HCF model will help the drilling engineers to avoid many issues while drilling such as cutting accumulation and drill pipe sticking. The predictability of the HCF model was compared with commercially available software, and the results indicated a good match between the predictability of the HCF model and the commercial software.

scholarly journals Leakage dynamics of fault zones: experimental and analytical study with application to CO2 storage

2021 ◽  
Vol 931 ◽  
Author(s):  
Kieran A. Gilmore ◽  
Chunendra K. Sahu ◽  
Graham P. Benham ◽  
Jerome A. Neufeld ◽  
Mike J. Bickle
Keyword(s):  
Porous Medium ◽  
Co2 Storage ◽  
Gravity Current ◽  
Fault Zones ◽  
Analytical Models ◽  
Fluid Distribution ◽  
Pressure Gradients ◽  
Storage Security ◽  
Darcy Velocity ◽  
Basin Scale

Fault zones have the potential to act as leakage pathways through low permeability structural seals in geological reservoirs. Faults may facilitate migration of groundwater contaminants and stored anthropogenic carbon dioxide (CO $_2$ ), where the waste fluids would otherwise remain securely trapped. We present an analytical model that describes the dynamics of leakage through a fault zone cutting multiple aquifers and seals. Current analytical models for a buoyant plume in a semi-infinite porous media are combined with models for a leaking gravity current and a new model motivated by experimental observation, to account for increased pressure gradients within the fault due to an increase in Darcy velocity directly above the fault. In contrast to previous analytical fault models, we verify our results using a series of analogous porous medium tank experiments, with good matching of observed leakage rates and fluid distribution. We demonstrate the utility of the model for the assessment of CO $_2$ storage security, by application to a naturally occurring CO $_2$ reservoir, showing the dependence of the leakage rates and fluid distribution on the fault/aquifer permeability contrast. The framework developed within this study can be used for quick assessment of fluid leakage through fault zones, given a set of input parameters relating to properties of the fault, aquifer and fluids, and can be incorporated into basin-scale models to improve computational efficiency. The results show the utility of using analytical methods and reduced-order modelling in complex geological systems, as well as the value of laboratory porous medium experiments to verify results.

Experimental Study of Laminar Displacement Flows in Narrow Horizontal Eccentric Annuli

2020 ◽  
Author(s):  
Alondra Renteria ◽  
Yee Voon Liew ◽  
Ian Frigaard
Keyword(s):  
Viscosity Ratio ◽  
High Sensitivity ◽  
Secondary Flows ◽  
Flow Loop ◽  
Fluid Displacement ◽  
Eccentric Annulus ◽  
Model Predictions ◽  
Dimensional Parameters ◽  
Primary Cementing ◽  
Fluid Rheology

Abstract Wells with poor cement jobs are prone to develop paths where the hydrocarbons might leak to the surface. Such events cause environmental risks and costly repairs. Even though horizontal wells have been drilled since the 1980s, studies on the dynamics of the fluid-fluid displacement under this configuration are scarce. In this work, we present experiments on the displacement of two Newtonian fluids in laminar regime in a horizontal uniform annulus. The minimum non-dimensional parameters required to describe the flow under such conditions include a buoyancy number (b), viscosity ratio (μ2/μ1) and eccentricity (e). We have designed and built a flow loop that mimics the annular displacement under controlled and dimensionlessly comparable conditions found in field. Within this apparatus we can set key process parameters: flow rate, eccentricity, fluid rheology and density. Data acquisition is through imaging with high sensitivity cameras and partially automated instrumentation. Preliminary results of the experiments show that there is a subtle balance between eccentricity and buoyancy. Sufficiently high values of |b| will end up in stratification of the fluids. The secondary flows created in an eccentric annulus compete against a positive buoyancy, driving the flow to the wide side (top) at moderate values of b. The effect of the viscosity ratio is most relevant at small values of b. The experimental data from this work can be compared against both mathematical model predictions and computational simulations used in the design of primary cementing jobs.

Secondary convection in a Hele Shaw cell

1975 ◽  
Vol 71 (4) ◽  
pp. 675-687 ◽  
Author(s):  
Lloyd L. Green ◽  
Theodore D. Foster
Keyword(s):  
Salt Water ◽  
Water Layer ◽  
Density Field ◽  
Pressure Gradients ◽  
Theoretical Comparison ◽  
Horizontal Pressure ◽  
Wavelength Variation ◽  
Rayleigh Numbers ◽  
Horizontal Wavelength ◽  
Hele Shaw Cell

A convective instability is produced by salt water diffusing onto the surface of a fresh-water layer in a Hele Shaw cell. Although the horizontal wavelength of the initial instability is small, an increase in the horizontal wavelength of the convective flow with time and depth is observed as the resulting two-dimensional convection develops. The phenomenon of wavelength variation is confirmed numerically, but quantitative observational and theoretical comparison is limited to small Rayleigh numbers. It is shown that perturbations in the density field cause horizontal pressure gradients, which in turn cause convective elements to combine.

Some problems of objective-prism spectra classification

1966 ◽  
Vol 24 ◽  
pp. 51-52
Author(s):  
E. K. Kharadze ◽  
R. A. Bartaya
Keyword(s):  
Short Wave ◽  
High Quality ◽  
Stellar Spectra ◽  
Objective Prism

The unique 70-cm meniscus-type telescope of the Abastumani Astrophysical Observatory supplied with two objective prisms and the seeing conditions characteristic at Mount Kanobili (Abastumani) permit us to obtain stellar spectra of a high quality. No additional design to improve the “climate” immediately around the telescope itself is being applied. The dispersions and photographic magnitude limits are 160 and 660Å/mm, and 12–13, respectively. The short-wave end of spectra reaches 3500–3400Å.

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