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Using pneumatic fracturing to reduce borehole damage in wells in southern Florida
Title
Using pneumatic fracturing to reduce borehole damage in wells in southern Florida.
Creator
Sunderland, R. Simon A., Florida Atlantic University, Finkl, Charles W.
Abstract/Description
Two wells installed in an unconfined, sandy aquifer in southern Florida exhibited low specific capacities and well loss coefficients resulting from borehole damage from drilling. Hollow-stem augers used to install the wells smeared drill cuttings onto the borehole walls reducing the hydraulic connection between the wells and the aquifer. Pneumatic fracturing was used to improve the specific capacity of both wells by improving the hydraulic connection with the aquifer. The pneumatic fracturing...
Show moreTwo wells installed in an unconfined, sandy aquifer in southern Florida exhibited low specific capacities and well loss coefficients resulting from borehole damage from drilling. Hollow-stem augers used to install the wells smeared drill cuttings onto the borehole walls reducing the hydraulic connection between the wells and the aquifer. Pneumatic fracturing was used to improve the specific capacity of both wells by improving the hydraulic connection with the aquifer. The pneumatic fracturing involved injecting air under high pressure into the surrounding formation to create a network of fractures. The success of the pneumatic fracturing was evaluated by recalculating the specific capacity and well loss coefficient of each well after the event. The results showed that both wells operated at increased discharge rates with improved specific capacities and well loss coefficients. High head loss coefficients indicated that the borehole damage was not completely repaired.
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Date Issued
1999
PURL
http://purl.flvc.org/fcla/dt/15674
Subject Headings
Wells--Florida, Fracture mechanics--Environmental aspects, Pneumatics--Environmental aspects
Format
Document (PDF)
UNDERSTANDING GRAVITY DRIVEN PARTICLE SETTLING AND DISTRIBUITION IN FRACTURES
Title
UNDERSTANDING GRAVITY DRIVEN PARTICLE SETTLING AND DISTRIBUITION IN FRACTURES.
Creator
Hafez, Mazen, Kim, Myeongsub, Florida Atlantic University, Department of Ocean and Mechanical Engineering, College of Engineering and Computer Science
Abstract/Description
The elevated energy demand and high dependency on fossil fuels have directed researchers’ attention to promoting and advancing hydraulic fracturing (HF) operations for a sustainable energy future. Previous studies have demonstrated that the particle suspension and positioning in slick water play a vital role during the injection and shut-in stages of the HF operations. A significant challenge to HF is the premature particle settling and uneven particle distribution in a formation. Even though...
Show moreThe elevated energy demand and high dependency on fossil fuels have directed researchers’ attention to promoting and advancing hydraulic fracturing (HF) operations for a sustainable energy future. Previous studies have demonstrated that the particle suspension and positioning in slick water play a vital role during the injection and shut-in stages of the HF operations. A significant challenge to HF is the premature particle settling and uneven particle distribution in a formation. Even though various research was conducted on the topic of particle transport, there still exist gaps in the fundamental particle-particle interaction mechanisms. This dissertation utilizes both experimental and numerical approaches to advance the state of the art in particle-particle interactions in various test conditions. Experimentally, the study utilizes high-speed imaging coupled with particle tracking velocimetry (PTV) and particle image velocimetry (PIV) to provide a space and time-resolved investigation of both two-particle and multi-particle interactions during gravitational settling, respectively.
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Date Issued
2022
PURL
http://purl.flvc.org/fau/fd/FA00014095
Subject Headings
Hydraulic fracturing, Particle image velocimetry, Particle tracking velocimetry, Fluid mechanics research
Format
Document (PDF)
Some corrosion problems associated with underwater turbines
Title
Some corrosion problems associated with underwater turbines.
Creator
Miglis, Yohann., College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
Abstract/Description
This thesis deals with corrosion problems of underwater turbines in marine environment. The effect of a tensile stress on the uniform corrosion rate of a metal bar is studied, and an analytical model predicting the time of service of a bar under a tensile load in a corrosive environment is proposed. Stress corrosion relationships are provided for different type of alloys, and different types of relationships. Dolinskii's and Gutman's models are studied and extended to a general order...
Show moreThis thesis deals with corrosion problems of underwater turbines in marine environment. The effect of a tensile stress on the uniform corrosion rate of a metal bar is studied, and an analytical model predicting the time of service of a bar under a tensile load in a corrosive environment is proposed. Stress corrosion relationships are provided for different type of alloys, and different types of relationships. Dolinskii's and Gutman's models are studied and extended to a general order polynomial, along with a Least Square and Spline Interpolation of the experimental data. In a second part, the effect of the passive film, delaying the initiation of the corrosion process, is studied. Finally, an algorithm predicting the time of service of a cracked bar is provided, using the stress corrosion assumption, along with a validation using experimental data.
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Date Issued
2012
PURL
http://purl.flvc.org/FAU/3342238
Subject Headings
Turbines, Stress corrosion, Testing, Computational fluid dynamics, Stress corrosion, Fracture mechanics, Measurement, Alloys, Stress corrosion, Testing, Alloys, Corrosion fatigue, Testing
Format
Document (PDF)
Development of a morphing autonomous underwater vehicle for path and station keeping in complex current environments
Title
Development of a morphing autonomous underwater vehicle for path and station keeping in complex current environments.
Creator
Meneses, Andrea M., Su, Tsung-Chow, Florida Atlantic University, College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
Abstract/Description
This thesis explores the feasibility of using morphing rudders in autonomous underwater vehicles (AUVs) to improve their performance in complex current environments. The modeling vehicle in this work corresponds to the Florida Atlantic University's Ocean EXplorer (OEX) AUV. The AUV nonlinear dynamic model is limited to the horizontal plane and includes the effect of ocean current. The main contribution of this thesis is the use of active rudders to successfully achieve path keeping and...
Show moreThis thesis explores the feasibility of using morphing rudders in autonomous underwater vehicles (AUVs) to improve their performance in complex current environments. The modeling vehicle in this work corresponds to the Florida Atlantic University's Ocean EXplorer (OEX) AUV. The AUV nonlinear dynamic model is limited to the horizontal plane and includes the effect of ocean current. The main contribution of this thesis is the use of active rudders to successfully achieve path keeping and station keeping of an AUV under the influence of unsteady current force. A constant ocean current superimposed with a sinusoidal component is considered. The vehicle's response is analyzed for a range of current frequencies.
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Date Issued
2014
PURL
http://purl.flvc.org/fau/fd/FA00004137, http://purl.flvc.org/fau/fd/FA00004137
Subject Headings
Autonomous robots -- Design and construction, Fracture mechanics, Manipulation (Mechanism) -- Control, Remote submersibles -- Design and construction, Vehicles, Remotely piloted -- Design and construction
Format
Document (PDF)

Pages