Development and application of triaxial rock shear - self-supporting fracture conductivity experiment system

In the case of fracturing of the reservoirs using fracturing fluids, the size of damage to the proppant conductivity caused by treatment fluids is significant, which greatly influence the effective execution of hydraulic fracturing operations. The fracturing fluid should be characterized by the minimum damage to the conductivity of a fracture filled with proppant. A laboratory research procedure has been developed to study the damage effect caused by foamed and non-foamed fracturing fluids in the fractures filled with proppant material. The paper discusses the results for high quality foamed guar-based linear gels, which is an innovative aspect of the work compared to the non-foamed frac described in most of the studies and simulations. The tests were performed for the fracturing fluid based on a linear polymer (HPG—hydroxypropyl guar, in liquid and powder form). The rheology of nitrogen foamed-based fracturing fluids (FF) with a quality of 70% was investigated. The quartz sand and ceramic light proppant LCP proppant was placed between two Ohio sandstone rock slabs and subjected to a given compressive stress of 4000–6000 psi, at a temperature of 60 °C for 5 h. A significant reduction in damage to the quartz proppant was observed for the foamed fluid compared to that damaged by the 7.5 L/m3 natural polymer-based non-foamed linear fluid. The damage was 72.3% for the non-foamed fluid and 31.5% for the 70% foamed fluid, which are superior to the guar gum non-foamed fracturing fluid system. For tests based on a polymer concentration of 4.88 g/L, the damage to the fracture conductivity by the non-foamed fluid was 64.8%, and 26.3% for the foamed fluid. These results lead to the conclusion that foamed fluids could damage the fracture filled with proppant much less during hydraulic fracturing treatment. At the same time, when using foamed fluids, the viscosity coefficient increases a few times compared to the use of non-foamed fluids, which is necessary for proppant carrying capacities and properly conducted stimulation treatment. The research results can be beneficial for optimizing the type and performance of fracturing fluid for hydraulic fracturing in tight gas formations.

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The Static Mechanical Property of Concrete at Elevated Temperature

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.261-263.212 ◽

2011 ◽

Vol 261-263 ◽

pp. 212-216

Author(s):

Jun Lin Tao ◽

Li Bo Qin ◽

Kui Li ◽

Bin Jia

Keyword(s):

Mechanical Property ◽

Elevated Temperature ◽

Room Temperature ◽

Critical Strain ◽

Plain Concrete ◽

Constitutive Relationship ◽

Heating Method ◽

Experiment System ◽

Wave Heating ◽

Static Mechanical

Using micro-wave heating method, the previous disadvantages of heating slowly and non-uniform are broken through. And plain concrete high temperature loading experiment system is composed of the method and material experiment machine. Many experiments of self-made concrete are carried out from room temperature to 600°C by this system. The strength and critical strain of concrete with temperature are obtained, and through analysis of the compressive stress-strain curves under different temperature, the constitutive relationship is established. The result shows that this constitutive relationship is greatly agrees with experiment. Meanwhile, the phenomenon is analyzed and explained in the progress of experiment.

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Design and Application of Pocket Experiment System Based on STM32F4

2020 The 8th International Conference on Information Technology: IoT and Smart City ◽

10.1145/3446999.3447007 ◽

2020 ◽

Author(s):

YANYUN ZHOU ◽

FEI SHI ◽

JUAN CHEN

Keyword(s):

Experiment System ◽

Design And Application

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Performance Evaluation of Enzyme Breaker for Fracturing Applications under Simulated Reservoir Conditions

Molecules ◽

10.3390/molecules26113133 ◽

2021 ◽

Vol 26 (11) ◽

pp. 3133

Author(s):

Yuling Meng ◽

Fei Zhao ◽

Xianwei Jin ◽

Yun Feng ◽

Gangzheng Sun ◽

...

Keyword(s):

Hydraulic Fracturing ◽

Shear Resistance ◽

Ammonium Persulfate ◽

Fracturing Fluid ◽

Medium Temperature ◽

Fracture Conductivity ◽

Wide Range ◽

Reservoir Conditions ◽

Alkaline Conditions ◽

Resistance Performance

Fracturing fluids are being increasingly used for viscosity development and proppant transport during hydraulic fracturing operations. Furthermore, the breaker is an important additive in fracturing fluid to extensively degrade the polymer mass after fracturing operations, thereby maximizing fracture conductivity and minimizing residual damaging materials. In this study, the efficacy of different enzyme breakers was examined in alkaline and medium-temperature reservoirs. The parameters considered were the effect of the breaker on shear resistance performance and sand-suspending performance of the fracturing fluid, its damage to the reservoir after gel breaking, and its gel-breaking efficiency. The experimental results verified that mannanase II is an enzyme breaker with excellent gel-breaking performance at medium temperatures and alkaline conditions. In addition, mannanase II did not adversely affect the shear resistance performance and sand-suspending performance of the fracturing fluid during hydraulic fracturing. For the same gel-breaking result, the concentration of mannanase II used was only one fifth of other enzyme breakers (e.g., mannanase I, galactosidase, and amylase). Moreover, the amount of residue and the particle size of the residues generated were also significantly lower than those of the ammonium persulfate breaker. Finally, we also examined the viscosity-reducing capability of mannanase II under a wide range of temperatures (104–158 °F) and pH values (7–8.5) to recommend its best-use concentrations under different fracturing conditions. The mannanase has potential for applications in low-permeability oilfield development and to maximize long-term productivity from unconventional oilwells.

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Study on Influence of Diameter on Detonation Acoustic Characteristics of Pulse Detonation Engine

International Journal of Turbo and Jet Engines ◽

10.1515/tjj-2020-0003 ◽

2020 ◽

Vol 0 (0) ◽

Author(s):

Gui-yang Xu ◽

Chun-guang Wang ◽

Yan-fang Zhu ◽

Hong-yan Li ◽

Lun-kun Gong ◽

...

Keyword(s):

Acoustic Characteristic ◽

Pulse Detonation Engine ◽

Acoustic Characteristics ◽

Experiment System ◽

Pulse Detonation ◽

Impact Noise ◽

Maximum Duration ◽

Detonation Engine ◽

Set Up ◽

Different Diameters

AbstractThe experiment system of pulse detonation engine is set up to investigate on influence of diameter on detonation acoustic characteristic. The research of detonation acoustic characteristic of pulse detonation engine for four different diameters in different angles is carried out. Results from the test show that as the PDE diameter increasing, there are increases in amplitudes of impact noise in all angles, and the growth rate of amplitude of impact noise in the 90° direction is generally greater than that in the 0° direction. The smaller PDE diameter is, the distance of most obvious directivity at 0° turning to most obvious directivity at 30° is shorter. When the distance is shorter, such as 200 mm, the duration of detonation acoustic is increasing with the increase of PDE diameter, however, when the distance is longer, such as 3000 mm, it is just the opposite. The maximum duration of detonation acoustic is appeared in 3000 mm under 30 mm PDE diameter which reaches to 1.44 ms.

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