Search

To investigate the fracture propagation mechanism of horizontal wells during hydraulic fracturing, a new semi-analytical and semi-numerical simulation method for multiple fractures propagation was established to simulate the competitive propagation of multiple fractures by combining the dimensionless approximate solution with the energy conservation. A high-precision and high-efficiency fracture propagation program named C5Frac was developed. The method was used to simulate the propagation of single and multiple fractures, and implicit level set algorithm(ILSA) II was used for comparative verification. The results show that for single fracture propagation, the error between fracture radius, width at fracture mouth and fluid efficiency calculated by C5Frac and the reference solution is within 1% . For multiple fractures propagation, the simulation results of dimensionless fracture radius, flow rate inside fracture and width at fracture mouth calculated by C5Frac are very close to ILSA II, and the error of total fracture area is within 5% . In addition, the computational efficiency is significantly improved. The method can greatly reduce computational time while ensuring the accuracy of the results, which provides a new approach for the numerical simulation of multiple fractures propagation. [ABSTRACT FROM AUTHOR]

Copyright of Science Technology & Engineering is the property of Chinese Society of Technology Economics and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Petroleum Geology & Recovery Efficiency is the property of Petroleum Geology & Recovery Efficiency and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Plastics Science & Technology / Suliao Ke-Ji is the property of Plastics Science & Technology Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Nanjing Medical University: Natural Sciences is the property of Journal of Nanjing Medicial University (NMU) Medical Publications Center and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Shenzhen University Science & Engineering is the property of Editorial Department of Journal of Shenzhen University Science & Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Surface dielectric barrier discharge can produce atmospheric low temperature plasmas, which has great application potential in the field of air purification.To investigate the effects of electrode gap on the generation of ozone and nitrogen oxides in surface dielectric barrier discharge, a two-dimensional fluid model was developed.The numerical simulation results indicated that the number and amplitude of current pulses decreased with the increase of electrode gap in the rising phase of microsecond-pulse voltage.Ozone density can be improved by decreasing the electrode gap, but increasing electrode gap was favorable for the improvement of ozone yield.NO density decreased with the increase of electrode gap, while the other nitrogen oxides remained almost unchanged.This study provided a comprehensive simulation analysis of the useful and harmful substances in the surface dielectric barrier discharge, which can provide some help for the design and optimization of the surface dielectric barrier discharge ozone generator. [ABSTRACT FROM AUTHOR]

Ion-induced secondary electron emission (SEE) was the fundamental physical process for low temperature plasmas.The dielectric surface charge played an important role in the process of SEE,which affects the dynamics of plasma discharge.Compared to the previous model which simplifies the electronic structure and the parameter of surface charges, a more accurate method based on Auger neutralization and the density functional theory (DFT) model was applied to calculate the secondary electron emission coefficient (SEEC) of MgO with accumulated surface charge in the atmospheric pressure helium dielectric barrier discharge (DBD) with nitrogen impurities.It discussed the influence of SEEC considering dielectric surface charge on the spatiotemporal characteristics of DBD.In order to observe the effect of dielectric surface charge on the secondary electron emission process, it introduced the peak-leveled voltage which carry little dielectric surface charge during the discharge process to compare with the sinusoidal voltage.The simulation results showed that when the SEE process considering the dielectric surface charge, the current waveform done not change obviously under the peak-leveled voltage.However, under the sinusoidal voltage, the phase of the discharge moment was advanced, the current amplitude was significantly reduced and the spatial distribution of electrons was more dispersed.The result further verifies the effectiveness of the DFT model in our work, and lays a theoretical foundation for the further study of the physical process of DBD discharge. [ABSTRACT FROM AUTHOR]

Copyright of China Plastics / Zhongguo Suliao is the property of Journal Office of CHINA PLASTICS and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Acta Sedimentologica Sinica is the property of Acta Sedimentologica Sinica Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Natural Gas Geoscience is the property of Natural Gas Geoscience and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Research & Exploration in Laboratory is the property of Research & Exploration in Laboratory and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)