The Experts below are selected from a list of 102 Experts worldwide ranked by ideXlab platform
Mohd Faisal Rasdi - One of the best experts on this subject based on the ideXlab platform.
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diagnosing fracture network pattern and flow regime aids production performance analysis in unconventional oil reservoirs
SPE EAGE European Unconventional Resources Conference & Exhibition - From Potential to Production, 2012Co-Authors: Mohd Faisal RasdiAbstract:Many tight or shale gas wells exhibit a linear flow regime that can last for years. However, production analysis in unconventional oil reservoirs, such as the Bakken, shows that the linear flow regime is not the only dominant flow regime. Field data suggest that the duration of boundary-dominated flow influenced by the stimulated-reservoir volume (SRV) and compound-linear flow generally overshadow the early-time linear flow regime. Depending on the fracture network or SRV patterns, formation linear flow in unconventional oil reservoirs may only last for a few months but contribute about 30% of the total estimated ultimate recovery (EUR). This study develops a procedure for identification of different fracture network patterns and inference of related flow parameters based on analytical methods. The reservoir description so derived is transported to a numerical reservoir-flow simulation model to capture the Effects of compaction, multiphase flow behavior, and various flow regimes in an unconventional oil reservoir system. This coupled approach helps illuminate reservoir performance, which allows insights into history matching. In particular, we demonstrate (a) fracture network patterns and flow regime diagnosis through rate-transient analysis; (b) coupled numerical reservoir simulation with analytical modeling results for performance-constrained history matching; (c) sensitivity analysis on the Heterogeneity Effect, compaction Effect, and multiphase flow Effects; and (d) field application of the proposed procedure on Bakken wells. This proposed method demonstrates that analytical methods should be used before undertaking a detailed numerical reservoirflow simulation study. This understanding paves the way for much improved reservoir characterization in unconventional oil reservoirs.
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diagnosing fracture network pattern and flow regime aids production performance analysis in unconventional oil reservoirs
SPE EAGE European Unconventional Resources Conference & Exhibition - From Potential to Production, 2012Co-Authors: Mohd Faisal RasdiAbstract:Many tight or shale gas wells exhibit a linear flow regime that can last for years. However, production analysis in unconventional oil reservoirs, such as the Bakken, shows that the linear flow regime is not the only dominant flow regime. Field data suggest that the duration of boundary-dominated flow influenced by the stimulated-reservoir volume (SRV) and compound-linear flow generally overshadow the early-time linear flow regime. Depending on the fracture network or SRV patterns, formation linear flow in unconventional oil reservoirs may only last for a few months but contribute about 30% of the total estimated ultimate recovery (EUR). This study develops a procedure for identification of different fracture network patterns and inference of related flow parameters based on analytical methods. The reservoir description so derived is transported to a numerical reservoir-flow simulation model to capture the Effects of compaction, multiphase flow behavior, and various flow regimes in an unconventional oil reservoir system. This coupled approach helps illuminate reservoir performance, which allows insights into history matching. In particular, we demonstrate (a) fracture network patterns and flow regime diagnosis through rate-transient analysis; (b) coupled numerical reservoir simulation with analytical modeling results for performance-constrained history matching; (c) sensitivity analysis on the Heterogeneity Effect, compaction Effect, and multiphase flow Effects; and (d) field application of the proposed procedure on Bakken wells. This proposed method demonstrates that analytical methods should be used before undertaking a detailed numerical reservoirflow simulation study. This understanding paves the way for much improved reservoir characterization in unconventional oil reservoirs.
Habib Safigholi - One of the best experts on this subject based on the ideXlab platform.
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su e t 378 evaluation of an analytical model for the inter seed attenuation Effect in 103 pd multi seed implant brachytherapy
Medical Physics, 2015Co-Authors: Habib Safigholi, Soleimani A Meigooni, D Han, A Soliman, W SongAbstract:Purpose: Brachytherapy treatment planning systems based on TG-43 protocol calculate the dose in water and neglects the Heterogeneity Effect of seeds in multi-seed implant brachytherapy. In this research, the accuracy of a novel analytical model that we propose for the inter-seed attenuation Effect (ISA) for 103-Pd seed model is evaluated. Methods: In the analytical model, dose perturbation due to the ISA Effect for each seed in an LDR multi-seed implant for 103-Pd is calculated by assuming that the seed of interest is active and the other surrounding seeds are inactive. The cumulative dosimetric Effect of all seeds is then summed using the superposition principle. The model is based on pre Monte Carlo (MC) simulated 3D kernels of the dose perturbations caused by the ISA Effect. The cumulative ISA Effect due to multiple surrounding seeds is obtained by a simple multiplication of the individual ISA Effect by each seed, the Effect of which is determined by the distance from the seed of interest. This novel algorithm is then compared with full MC water-based simulations (FMCW). Results: The results show that the dose perturbation model we propose is in excellent agreement with the FMCW values for a case with three seeds separated by 1 cm. The average difference of the model and the FMCW simulations was less than 8%±2%. Conclusion: Using the proposed novel analytical ISA Effect model, one could expedite the corrections due to the ISA dose perturbation Effects during permanent seed 103-Pd brachytherapy planning with minimal increase in time since the model is based on multiplications and superposition. This model can be applied, in principle, to any other brachytherapy seeds. Further work is necessary to validate this model on a more complicated geometry as well.
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su e t 525 developing a gyn cs selectron brachytherapy treatment planning software accounting for inter source applicator and Heterogeneity Effects
Medical Physics, 2013Co-Authors: Habib Safigholi, M Moslehshirazi, Dariush Sardari, S Karbasi, F Massicano, H Yoriyaz, S Sina, Karimi S Jashni, Guedes R Possoni, Ali S. MeigooniAbstract:Purpose: In this project new treatment software based on TG‐43U1 and Monte Carlo (MC) simulations for treatment of GYN cancers were developed. This treatment software accounted for inter‐source Effect, applicator attenuation, and tissue Heterogeneity for Cs‐137 selectron machine. Methods: MC Linear TG‐43U1 functions for combination of 8 active‐inactive pellets with 2 cm physical length for filling tandem and ovoid were obtained. Total length of tandem and ovoid filled with three and one linear sources, respectively. With this approach inter‐source Effect and applicator attenuations have been hidden in TG‐43U1 functions. To account Heterogeneity Effect in software design, the library of dose inhomogeneity correction factor (DICF) for various different thickness and position respect to one active Cs pellet for air and aluminum (as a bone) were simulated. A non‐homogen GYN polyethylene phantom were designed, which contain a cylinder of air as a rectum, and two symmetric aluminum spheres as a femur bone heads. GYN reference dosimetry points for TLD detectors were machined in the phantom according ICRU‐38 report. Finally reference points dose rate were compared using new software, STPS software, TLD measurements and full MC simulations. Results: New software data have good agreement with TLD and MC simulations (up to 5%). However STPS data for more reference points are less than TLD and MC simulation (up to 3%) due to not considered applicators and inter‐source attenuation. For tip of tandem and ovoid STPS data are more than TLD, and MC about 26% and 17%, respectively. More over DICF data can create data with accuracy of 2% in comparison to TLD and MC measurements. Conclusion: In this project for first time developed a 3D GYN‐Cs‐Selectron treatment planning software (TPS) based on Linear TG‐43U1 functions and libraries of MC simulations which modified inter‐source Effect, applicator attenuations, and Heterogeneity Effects.
Reza Barati - One of the best experts on this subject based on the ideXlab platform.
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a review of the current progress of co2 injection eor and carbon storage in shale oil reservoirs
Fuel, 2019Co-Authors: Jyunsyung Tsau, Reza BaratiAbstract:Abstract CO2 injection is a promising method to rejuvenate the shale oil reservoirs after the primary production. In this work, we comprehensively reviewed the CO2 injection enhanced oil recovery (EOR) and carbon storage related literature in shales over the past decade. The aspects reviewed include description of major shale reservoirs producing oil and the necessity to perform EOR, selection of injection scheme, models applied to simulate gas injection, oil recovery mechanisms for different types of gas, molecular diffusion and its laboratory measurement, nanopore Effect, adsorption Effect on carbon storage and transport, laboratory work of gas injection in shale cores, pilot tests, and economic evaluation. Advanced models in recent years applied to simulate these processes were introduced in details, such as the traditional dual continuum model, the embedded discrete fracture model (EDFM). Heterogeneity Effect and upscaling algorithm on the shale oil recovery performance were discussed. Molecular diffusion, as an important flow and oil recovery mechanism, was described regarding its definition, empirical correlation and laboratory measurement with consideration of the porous media Effect which is crucial for accurate modeling result. Recovery mechanisms by carbon dioxide, methane and nitrogen were compared at the molecule and pore levels. Pros and cons of different types of gas were evaluated as well. Pore confinement caused by the extremely tiny pores in the organic matter, along with the capillary and adsorption Effects were discussed, and approaches to take them into account of the model were addressed. Core-scale gas injection experiments on shales from various institutions were described, and the results were compared. Outcomes of recent pilot tests in the Eagle Ford, and the Bakken formations were summarized, and finally, economic considerations were provided for the feasibility of gas injection in shale oil reservoirs.
Artur Paiva Coutinho - One of the best experts on this subject based on the ideXlab platform.
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Vadose Zone Heterogeneity Effect on Unsaturated Water Flow Modeling at Meso-Scale
2016Co-Authors: Artur Paiva Coutinho, Thierry Winiarski, Laurent Lassabatere, Jaime Joaquim Da Silva, Pereira Cabral, Antonio Celso, Dantas Antonino, Rafael Angulo-jaramilloAbstract:The understanding of unsaturated flow in heterogeneous formations is a prerequisite to the un-derstanding of pollutant transfer in the vadose zone and the proper management of infiltration basins settled over such heterogeneous formations. This study addresses the Effect of lithological Heterogeneity of a glaciofluvial deposit on flow in the vadose zone underneath an infiltration basin settled in the Lyon suburbs. The basin had already been the subject of several previous studies, some of which demonstrated the impact of soil Heterogeneity. But all of them were only based on the sedimentological study of a trench and no study addressed the potential spatial variability of results due to the spatial variability of soil Heterogeneity. In this study, we model flow in the va-dose zone for several case studies, including drainage, water infiltration during a rainfall event, and a complete meteorological chronic. These calculations were conducted for several sections, previously characterized in the basin using GPR and sedimentological study and compared with
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vadose zone Heterogeneity Effect on unsaturated water flow modeling at meso scale
Journal of Water Resource and Protection, 2015Co-Authors: Artur Paiva Coutinho, Thierry Winiarski, Laurent Lassabatere, Jaime Joaquim Da Silva Pereira Cabral, Antonio Celso Dantas Antonino, Rafael AngulojaramilloAbstract:The understanding of unsaturated flow in heterogeneous formations is a prerequisite to the understanding of pollutant transfer in the vadose zone and the proper management of infiltration basins settled over such heterogeneous formations. This study addresses the Effect of lithological Heterogeneity of a glaciofluvial deposit on flow in the vadose zone underneath an infiltration basin settled in the Lyon suburbs. The basin had already been the subject of several previous studies, some of which demonstrated the impact of soil Heterogeneity. But all of them were only based on the sedimentological study of a trench and no study addressed the potential spatial variability of results due to the spatial variability of soil Heterogeneity. In this study, we model flow in the vadose zone for several case studies, including drainage, water infiltration during a rainfall event, and a complete meteorological chronic. These calculations were conducted for several sections, previously characterized in the basin using GPR and sedimentological study and compared with a blank (homogeneous section). The results clearly show that Heterogeneity impacts unsaturated flow and that these impacts depend upon the section considered. Some geometrical architectural and textural parameters were proposed to explain the spatial variability and Effect of the soil Heterogeneity on unsaturated flow, thus establishing the first step towards modeling unsaturated flow in the basin at the meso-scale.
Ali S. Meigooni - One of the best experts on this subject based on the ideXlab platform.
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su e t 525 developing a gyn cs selectron brachytherapy treatment planning software accounting for inter source applicator and Heterogeneity Effects
Medical Physics, 2013Co-Authors: Habib Safigholi, M Moslehshirazi, Dariush Sardari, S Karbasi, F Massicano, H Yoriyaz, S Sina, Karimi S Jashni, Guedes R Possoni, Ali S. MeigooniAbstract:Purpose: In this project new treatment software based on TG‐43U1 and Monte Carlo (MC) simulations for treatment of GYN cancers were developed. This treatment software accounted for inter‐source Effect, applicator attenuation, and tissue Heterogeneity for Cs‐137 selectron machine. Methods: MC Linear TG‐43U1 functions for combination of 8 active‐inactive pellets with 2 cm physical length for filling tandem and ovoid were obtained. Total length of tandem and ovoid filled with three and one linear sources, respectively. With this approach inter‐source Effect and applicator attenuations have been hidden in TG‐43U1 functions. To account Heterogeneity Effect in software design, the library of dose inhomogeneity correction factor (DICF) for various different thickness and position respect to one active Cs pellet for air and aluminum (as a bone) were simulated. A non‐homogen GYN polyethylene phantom were designed, which contain a cylinder of air as a rectum, and two symmetric aluminum spheres as a femur bone heads. GYN reference dosimetry points for TLD detectors were machined in the phantom according ICRU‐38 report. Finally reference points dose rate were compared using new software, STPS software, TLD measurements and full MC simulations. Results: New software data have good agreement with TLD and MC simulations (up to 5%). However STPS data for more reference points are less than TLD and MC simulation (up to 3%) due to not considered applicators and inter‐source attenuation. For tip of tandem and ovoid STPS data are more than TLD, and MC about 26% and 17%, respectively. More over DICF data can create data with accuracy of 2% in comparison to TLD and MC measurements. Conclusion: In this project for first time developed a 3D GYN‐Cs‐Selectron treatment planning software (TPS) based on Linear TG‐43U1 functions and libraries of MC simulations which modified inter‐source Effect, applicator attenuations, and Heterogeneity Effects.