With easy oil recovered all across the world, the oil fields are depleting and extraction of heav... more With easy oil recovered all across the world, the oil fields are depleting and extraction of heavy oil is becoming more important. The exploration and drilling of new fields is expensive and time intensive. With most of the oil remaining is heavy and viscous; Enhanced Oil Recovery (EOR) methods are followed. Thermal EOR is the most widely used method in which steam injection is the most popular. Every year natural gas is burnt to produce steam and this amount is increasing as heavy oil reserves are developing all across the world. With increase in technological advancements and goal of reducing carbon emissions, solar energy is used to produce steam for the injection. This technology is called solar wells. The main objective is highlighting the cost of steam produced by natural gas and solar wells and finding investment, installation, operation and maintenance costs of these generators. Further, analyzing these costs, recommendations are made if new technology (solar wells) is worth the investment.
Evaluation of Test Specimen Geometry of Asphalt Mixes Tested with the Asphalt Mixture Performance... more Evaluation of Test Specimen Geometry of Asphalt Mixes Tested with the Asphalt Mixture Performance Tester Abha Dwivedy Asphalt concrete, AC, is a heterogeneous material that is modeled as a homogeneous material. The disparity between material structure and theory presents issue with performance testing with test sample geometries, resulting in variability. To accommodate this issue, the concept of Representative Volume Element, RVE, was developed. RVE is a term that expresses a concept that can be implemented through testing sample dimensions such as aspect ratios, diameter to aggregate size ratio, and gauge length. The laboratory test exhibit variabilities and therefore specimen size should be large enough to enable results representative of AC mix. As RVE of asphalt mix depends on aggregate size, shape, and orientation, it should be unique for each mix due to aggregate effect within the particular AC mix. The purpose of this research is to develop appropriate sample geometry for dynamic modulus, fatigue, and rutting test for accurate characterization of asphalt mix and ease of testing of three different NMAS mixes. Four sample geometries were fabricated for three mix types. All specimens are fabricated at 7%±0.5% air voids and tested for dynamic modulus, fatigue, and rutting in Asphalt Mixture Performance Tester, AMPT. The effect of sample geometry was statistically analyzed using laboratory test results and performance predictions using FlexPAVE. For ranking analysis all Sample Types, were compared to the full size AASHTO standard dimension used for up to 37.5 mm NMAS mixes for dynamic modulus and rutting test and for up to 25 mm NMAS mixes for fatigue test. Samples were also tested for air void uniformity using AASHTO R 83-17 for the three NMAS mixes. The lateral air void distribution from six different inscribed circles are also statistically analyzed. The MANOVA showed there is a statistical difference for different temperatures and frequencies in dynamic modulus test. This confirms that specific sample types be selected based on the mix NMAS for dynamic modulus test. More variability in air void distribution is observed axially than radially. The ST6, one 75X110 mm from one SGC pill, for 12.5 mm and 25 mm and ST4, three 50X110 mm from one SGC pill, for 19 mm NMAS mixes have uniform air void distribution from statistical analysis and performed comparable to ST1, one 100X150 mm from one SGC pill, from ranking analysis. These results provide detailed insight on correct sample dimension testing for performance prediction of 12.5 mm, 19 mm, and 25 mm NMAS asphalt mixes.
With easy oil recovered all across the world, the oil fields are depleting and extraction of heav... more With easy oil recovered all across the world, the oil fields are depleting and extraction of heavy oil is becoming more important. The exploration and drilling of new fields is expensive and time intensive. With most of the oil remaining is heavy and viscous; Enhanced Oil Recovery (EOR) methods are followed. Thermal EOR is the most widely used method in which steam injection is the most popular. Every year natural gas is burnt to produce steam and this amount is increasing as heavy oil reserves are developing all across the world. With increase in technological advancements and goal of reducing carbon emissions, solar energy is used to produce steam for the injection. This technology is called solar wells. The main objective is highlighting the cost of steam produced by natural gas and solar wells and finding investment, installation, operation and maintenance costs of these generators. Further, analyzing these costs, recommendations are made if new technology (solar wells) is worth the investment.
Evaluation of Test Specimen Geometry of Asphalt Mixes Tested with the Asphalt Mixture Performance... more Evaluation of Test Specimen Geometry of Asphalt Mixes Tested with the Asphalt Mixture Performance Tester Abha Dwivedy Asphalt concrete, AC, is a heterogeneous material that is modeled as a homogeneous material. The disparity between material structure and theory presents issue with performance testing with test sample geometries, resulting in variability. To accommodate this issue, the concept of Representative Volume Element, RVE, was developed. RVE is a term that expresses a concept that can be implemented through testing sample dimensions such as aspect ratios, diameter to aggregate size ratio, and gauge length. The laboratory test exhibit variabilities and therefore specimen size should be large enough to enable results representative of AC mix. As RVE of asphalt mix depends on aggregate size, shape, and orientation, it should be unique for each mix due to aggregate effect within the particular AC mix. The purpose of this research is to develop appropriate sample geometry for dynamic modulus, fatigue, and rutting test for accurate characterization of asphalt mix and ease of testing of three different NMAS mixes. Four sample geometries were fabricated for three mix types. All specimens are fabricated at 7%±0.5% air voids and tested for dynamic modulus, fatigue, and rutting in Asphalt Mixture Performance Tester, AMPT. The effect of sample geometry was statistically analyzed using laboratory test results and performance predictions using FlexPAVE. For ranking analysis all Sample Types, were compared to the full size AASHTO standard dimension used for up to 37.5 mm NMAS mixes for dynamic modulus and rutting test and for up to 25 mm NMAS mixes for fatigue test. Samples were also tested for air void uniformity using AASHTO R 83-17 for the three NMAS mixes. The lateral air void distribution from six different inscribed circles are also statistically analyzed. The MANOVA showed there is a statistical difference for different temperatures and frequencies in dynamic modulus test. This confirms that specific sample types be selected based on the mix NMAS for dynamic modulus test. More variability in air void distribution is observed axially than radially. The ST6, one 75X110 mm from one SGC pill, for 12.5 mm and 25 mm and ST4, three 50X110 mm from one SGC pill, for 19 mm NMAS mixes have uniform air void distribution from statistical analysis and performed comparable to ST1, one 100X150 mm from one SGC pill, from ranking analysis. These results provide detailed insight on correct sample dimension testing for performance prediction of 12.5 mm, 19 mm, and 25 mm NMAS asphalt mixes.
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