Master of Science (MS), Ohio University, 2022, Environmental Studies (Voinovich)

This study was designed to analyze the effect of the Palmiter method of stream restoration, adapted for infrastructure protection. Many roads and most bridges in the U.S. were built along or across rivers and streams. Rivers and streams are morphologically dynamic and naturally alter their channel over time, leading to bank erosion that can impact the stability of nearby infrastructure, requiring intervention in some cases, commonly by dumping riprap along the erosional surface. Riprap does not halt the problem and in some cases can exacerbate it. The Palmiter method uses mostly on site material and manual labor to relocate the channel away from the erosion issue by shifting the stream power away from the erosional area. Over time, the stream will erode the opposite bank and aggrade the restored bank. Eight sites, including three target reaches where the Palmiter method was used, three control reaches upstream of their respective target reaches, and two reference streams, were sampled four separate times (late July 2021, early September 2021, late October 2021, and late January 2022). Data on total suspended solids (TSS), flow, field water chemistry (field parameters), pebble size distribution, bank retreat, habitat quality, and the macroinvertebrate community were collected and analyzed statistically to determine associations between the Palmiter method and stream health. Most measures of stream health in this study were found to not be significantly different between target, reference, and control reaches. The exception was in stream cover assessed as part of the habitat evaluation and some of the smaller grain sizes in the pebble counts. This suggests that the Palmiter method can protect infrastructure without impairing stream health and can be applied to bank erosion leading to non-emergent infrastructure damage.

Committee: Natalie Kruse-Daniels (Committee Chair); Kelly Johnson (Committee Member); Benjamin Sperry (Committee Member) Subjects: Ecology; Engineering; Environmental Science; Natural Resource Management; Water Resource Management

Doctor of Philosophy, The Ohio State University, 1985, Graduate School

Committee: Not Provided (Other) Subjects: Engineering

PhD, University of Cincinnati, 2016, Engineering and Applied Science: Aerospace Engineering

It is common to convey solid particulates using liquids, forming a slurry. Those slurries conveyed in conduits generate erosion caused by particulate impingements on the walls. The erosive action of slurry may significantly reduce the service life of processing equipment, even at slow transport velocities. The particulates are subjected to the forces exerted by the carrying liquid. Therefore, continuous phase flow field strongly influences erosion by slurry. The erosive action and relevant flow features are investigated herein for a case of dilute slurry passing from the inner to the outer annulus through four equally spaced rectangular apertures on the periphery of a tube dividing these two conduits. This study consists of numerical and experimental investigations. The velocity and the Reynolds stresses were measured using Stereoscopic Particle Image Velocimetry. The erosive flow features of the continuous phase flow were identified and explored in detail. The measurements show that the flow develops high velocity near aperture edges directed towards the outermost wall. These measurements allowed validating the numerical solution of the continuous phase. The flow of dilute slurry was solved numerically. A consideration was given to the effects of particle size on erosion rate and statistical distribution of impact velocity, angle, and total erodent mass generating adverse wear rates. A confined trailing vortex forms at the longitudinal edge of the aperture, amplifying the erosive wear on the outer wall of the annulus. Also, large amount of particulates passes near the aperture horizontal downstream edge at high velocity and intensifies the erosion rate above it. The effect of these flow features becomes more pronounced for larger particulates. The statistical analysis of impact velocity, angle, and mass showed that the mean velocity in the channel dominates erosion caused by impacts of large particulates. On the other hand, the near-wall turbulence mai (open full item for complete abstract)

Committee: Ephraim Gutmark Ph.D. D.Sc. (Committee Chair); Shaaban Abdallah Ph.D. (Committee Member); Mark Turner Sc.D. (Committee Member) Subjects: Aerospace Materials

Doctor of Philosophy (PhD), Ohio University, 2015, Chemical Engineering (Engineering and Technology)

In oil and gas production, internal corrosion of pipelines causes the highest incidence of recurring failures. Ensuring the integrity of ageing pipeline infrastructure is an increasingly important requirement. One of the most widely applied methods to reduce internal corrosion rates is the continuous injection of chemicals in very small quantities, called corrosion inhibitors. These chemical substances form thin films at the pipeline internal surface that reduce the magnitude of the cathodic and/or anodic reactions. However, the efficacy of such corrosion inhibitor films can be reduced by different factors such as multiphase flow, due to enhanced shear stress and mass transfer effects, loss of inhibitor due to adsorption on other interfaces such as solid particles, bubbles and droplets entrained by the bulk phase, and due to chemical interaction with other incompatible substances present in the stream. The first part of the present project investigated the electrochemical behavior of two organic corrosion inhibitors (a TOFA/DETA imidazolinium, and an alkylbenzyl dimethyl ammonium chloride), with and without an inorganic salt (sodium thiosulfate), and the resulting enhancement. The second part of the work explored the performance of corrosion inhibitor under multiphase (gas/liquid, solid/liquid) flow. The effect of gas/liquid multiphase flow was investigated using small and large scale apparatus. The small scale tests were conducted using a glass cell and a submersed jet impingement attachment with three different hydrodynamic patterns (water jet, CO2 bubbles impact, and water vapor cavitation). The large scale experiments were conducted applying different flow loops (hilly terrain and standing slug systems). Measurements of weight loss, linear polarization resistance (LPR), and adsorption mass (using an electrochemical quartz crystal microbalance, EQCM) were used to quantify the effect of wall shear stress on the performance and integrity of corrosion inhibit (open full item for complete abstract)

Committee: Nesic Srdjan Dr. (Advisor) Subjects: Chemical Engineering; Chemistry; Materials Science; Metallurgy

MS, University of Cincinnati, 2012, Engineering and Applied Science: Aerospace Engineering

Thermal Barrier Coatings (TBC) have been developed for modern highly loaded turbines to allow their operation at higher temperatures than allowed by substrate blade material. TBC health is critical to blade life and to maintaining the high power output and efficiency achieved with the increased turbine inlet temperatures. However unlike blade material alloys, knowledge of thermal barriers' deterioration as a result of impacts by suspended particles in the flow field is very limited. The purpose of this study was to gain better knowledge of turbine blades thermal barrier coatings intensity and pattern of erosion by ingested particles in rotary wing engines. A commercial Computation Fluid Dynamics code, CFX, was used to perform two-phase flow simulations to supply flow and particle trajectory data. The suspended particles tend to deviate from the 3D flow path due to their higher inertia. User Defined Functions (UDF) were developed for restitution coefficients and erosion rate of thermal barrier coated surface based on previous experimentally based empirical models. The UDF was verified to correctly calculate restitution coefficients and erosion rates in a simulated high temperature erosion tunnel. The models were implemented in ANSYS CFX code which was used to predict the blade surface erosion rates for a gas turbine Auxiliary Power Unit (APU) used in currently operating rotary aircraft. Results are presented for the erosion rates of turbine blade thermal barrier coatings with uniform 36 micron alumina particle ingestion and for non-uniform particle ingestion concentrated in the 5% of the span near the annulus walls. Results for both cases are compared to those obtained from numerical simulations using fixed restitution default models at the blade surface impacts.

Committee: Awatef Hamed PhD (Committee Chair); Shaaban Abdallah PhD (Committee Member); Mark Turner ScD (Committee Member) Subjects: Aerospace Materials

PhD, University of Cincinnati, 2007, Engineering : Aerospace Engineering

The design and development of high performance turbomachinery operating in both ambient and high temperature environment in the presence of solid particles requires a thorough knowledge of the fundamental phenomena associated with particulate flow. Because of the serious consequences of turbomachinery erosion on their performance and life expectancy, it is important to have reliable methods for predicting their erosion when solid particles are ingested with the incoming flow. The ingestion of these solid particles over a period of time will reduce the efficiency of the propulsion system, causing increased fuel consumption and reduction in performance and thrust. Many studies, essential to predicting blade surface erosion intensity and pattern, have been conducted at the University of Cincinnati's Propulsion Laboratory in the past. The studies and experiments at the (UC) laboratory were performed in order to obtain a better understanding and a more realistic prediction of erosion rates of various conventional materials and coatings, while varying impingement angle, particle velocity, particle concentration, particle size, temperature and other important erosion parameters. Solid particle erosion is a complicated process which becomes even more complicated when it comes to composite material structures. In composite materials the mechanisms of erosion are complex, difficult to determine and even more difficult to predict due to the non-homogeneity of the material. Attempts were made to understand some of the basic mechanisms of erosion as early as the beginning of the (20th) century and continue even today. Over the years most of the attention of scientists was concentrated toward understanding the mechanisms occurring in conventional materials. However, due to the growing potential of composite materials and their desirable properties, they became a more focal point of interest.

Committee: Dr. Widen Tabakoff (Advisor) Subjects: Engineering, Aerospace

MS, University of Cincinnati, 2002, Engineering : Aerospace Engineering

The design and development of high performance turbomachinery operating in an ambient environment with solid particles require a thorough knowledge of the fundamental phenomenon associated with particulate flows. Because of the serious consequences of turbomachinery erosion on their performance and life, it is important to have reliable methods for predicting their erosion when solid particles are ingested with the incoming flow. The ingestion of these solid particles over a period of time will reduce the efficiency of the propulsion system, causing increased fuel consumption and decrease in thrust. Several studies, which are essential to predicting blade surface erosion intensity and pattern, have been conducted at the University of Cincinnati's Propulsion Laboratory over the past (30ty) years. This particular work describes only some investigation done on erosion behavior of materials and coatings exposed to different types of solid particles, velocities, temperatures, and impingement angles. For the present work the following materials and coatings were evaluated: (AA-22) Ceramic Material, Tungsten Carbide Cobalt (WC-Co) coating, Chromium Carbide Nickel (Cr 3C 2Ni) coating, and Titanium Nitride (TiN) coating. The erosive wear of the samples was studied experimentally by exposing them to particle-laden flow at velocities from (100 to 1000 ft/sec). The studied temperatures were between ambient (70°) and (1400°F) and impingement angles from (15° to 90°) degrees. The erosive particles used for the ambient and high temperature testing were: Runway Sand (100 and 1000 microns), Aluminum Oxide (Al 2 0 3 -27.5 microns), Crushed Quartz (60 microns), Arizona Test Dust (20 and 100 microns), and Silica Carbide (30 microns).

Committee: Dr. Widen Tabakoff (Advisor) Subjects:

Master of Arts (MA), Ohio University, 2010, Geography (Arts and Sciences)

This thesis uses field data on multiple gullied and ungullied roadcuts in Athens and Meigs Counties, Ohio, to investigate why gullies are present on some sites but not others and to explore relationships between site-specific landscape characteristics and the extent of gully erosion at different sites. Results show that gullied roadcuts have longer slopes than ungullied roadcuts and that the extent of gully erosion is related to the slope angle, slope length, and soil texture at roadcut sites. Extent of gullying tends to increase with increasing slope angle, slope length, and percentage sand.

Committee: Dorothy Sack PhD (Advisor); James Dyer PhD (Committee Member); James Lein PhD (Committee Member) Subjects: Geography

Master of Science (MS), Ohio University, 2008, Chemical Engineering (Engineering)

Erosion-corrosion occurs in pipelines that transport both corrosive liquids and erosive solid particles. This study has tested the erosion-corrosion behavior of mild carbon steel under conditions where there is no protective iron carbonate film. High and low salt concentrations were studied in order to determine the effect of salt concentration on the erosion-corrosion process. The effect of erosion-corrosion on mild steel was tested under disturbed flow by using a specially designed test section consisting of three flow alterations: a flow constriction, protrusion, and expansion. Under the tested conditions it was found that there is no synergistic effect between erosion and corrosion and that for an unprotected base metal the rate of metal loss is equal to the sum of erosion loss and corrosion loss. The higher salt concentration led to a lower corrosion rate and erosion rate but did notaffect the interaction between erosion and corrosion.

Committee: Srdjan Nesic (Advisor) Subjects:

MS, University of Cincinnati, 2024, Engineering and Applied Science: Aerospace Engineering

A major concern in the oil and gas industry is erosion corrosion which can cause catastrophic failure in pipelines. To monitor and prevent this failure, networks of acoustic emission sensors have been installed on pipelines to detect the presence of abrasive particles in the fluid flow. These abrasive particles damage the inside walls of the pipes through high-velocity impact. It would be advantageous to utilize the ultrasonic transducers in these existing monitoring systems to measure wall thickness. Two main roadblocks exist in utilizing these transducers for wall thickness measurements. First, these systems do not have a way of providing the typical excitation needed for ultrasonic measurements. To combat this issue, this thesis explores two different passive approaches: one that requires no purposeful excitation and another that utilizes acoustic emission from particle impact and fluid flow within the pipe. The second challenge in measuring wall thickness using existing transducers is the frequency range of these transducers which is much lower than what is typically used for ultrasonic time-of-flight thickness measurements. To address this problem, this thesis explores the sensitivity of transducers to the upper limits of their frequency range using a time-of-flight method. Additionally, for thinner-walled components which would require even higher frequencies, a resonant ultrasound spectroscopy method is explored. Experimental measurements using the different measurement modalities and passive excitation approaches are shown using multiple transducers. Several of the experimental combinations tested show good agreement with active measurements and show promise in determining wall thickness.

Committee: Joseph Corcoran Ph.D. (Committee Chair); Francesco Simonetti Ph.D. (Committee Member); Gui-Rong Liu Ph.D. (Committee Member) Subjects: Aerospace Engineering

Master of Science, The Ohio State University, 1960, Graduate School

Committee: Not Provided (Other) Subjects:

Master of Science, The Ohio State University, 1956, Graduate School

Committee: Not Provided (Other) Subjects:

Master of Science, University of Akron, 2024, Civil Engineering

Compost blankets have been used as a management practice over highway slopes, especially with disturbed soils, to mitigate runoff and soil erosion. However, it is yet to be employed in Ohio due to lack of research and specifications. This research focused on efficiency of 1”, 1.5” and 2” of Biosolids and Yard-waste compost blanket over 6:1 and 4:1 slope of disturbed soil in a lab-scale rainfall simulation, followed by field study on 1.5” Biosolids and Yard-waste. The assessment of vegetation coverage showed that Biosolids significantly outperformed both Yard-waste and control treatments (p<0.05). Grass density and health were notably better in Biosolids, although increasing compost thickness did not proportionally improve vegetation growth. Both Biosolids and Yard-waste effectively reduced runoff generation, with 2” Biosolids performing the best by reducing runoff volume by 96% to 98%. Compost blankets reduced total suspended solids (TSS) significantly compared to controls (p<0.05), particularly 2” Biosolids, which released the least TSS with almost 99.99% reduction. For Soluble Reactive Phosphorus (SRP), 2” Biosolids were the most effective treatment in reducing losses by 92% to 96% than control cases. Nitrate loss was not significantly reduced by any treatments on the 6:1 slope, but 1.5” Yard-waste (98%-99% reduction) and 2” Biosolids (86%-95% reduction) performed better than other treatments on the 4:1 slope. Both Biosolids and Yard-waste showed reduced Total Nitrogen (TN) and Total Potassium (TK) release compared to controls. With 98% to 100% TN reduction, 1” Yard-waste performed better than other treatments in both slopes. For TK, 1.5” Yard-waste had the highest reduction of 91% in 6:1 slope, but for 4:1 slope it was 1” Yard-waste with 84% reduction. Field tests compared 1.5” Biosolids and 1.5” Yard-waste with vegetated and unvegetated control cases, which demonstrated healthy vegetation growth in Biosolids within six weeks, requiring trimming to adhere to guid (open full item for complete abstract)

Committee: Teresa Cutright (Advisor); Ala Abbas (Committee Member); David Roke (Committee Member); Nariman Mahabadi (Committee Member) Subjects: Civil Engineering; Engineering; Environmental Engineering; Experiments; Geotechnology

Master of Science, The Ohio State University, 1955, Graduate School

Committee: Not Provided (Other) Subjects:

Master of Science, The Ohio State University, 2005, Graduate School

Committee: Not Provided (Other) Subjects:

Master of Science, The Ohio State University, 1979, Graduate School

Committee: Not Provided (Other) Subjects:

Master of Science, The Ohio State University, 2024, Aerospace Engineering

The role of quartz in gas turbine hot section deposition was investigated by varying both its size and percent concentration in Air Force Research Lab test dust (AFRL-02). The size distributions of quartz tested were 0 – 3 μm, 0 – 10 μm (baseline), and 10 – 20 μm while percent concentration ranged from 0% to 100%. The experiments replicated a gas turbine effusion cooling circuit with a flow temperature of 894K and plate surface temperature of 1144K. Aerosolized AFRL-02 dust was delivered to the test article, and capture efficiency, hole capture efficiency, blockage per gram, normalized deposit height, and effective area were recorded. A quartz size distribution of 0 – 3 μm showed the greatest deposition while 10 – 20 μm consistently deposited the least. Varying percent concentration of quartz had less obvious trends. While at a size distribution of 10 – 20 μm, increasing quartz concentration decreased deposition in all four assessment parameters. For a size distribution of 0 – 3 μm, increasing quartz concentration originally decreased deposition until greatly increasing it past a concentration of 68%. Quartz has been identified as a predominantly erosive mineral to deposits, but results suggest the size distribution contributes to deposition at a rate greater than or equal to percent concentration. The following study elucidates the effects of both size and concentration of quartz in a heterogenous mineral blend.

Committee: Jeffrey Bons (Advisor); Randall Mathison (Committee Member) Subjects: Aerospace Engineering

Doctor of Philosophy, University of Akron, 2024, Mechanical Engineering

High temperature materials such as Ceramic matrix composites (CMCs) have grown more and more popular for aerospace applications due to their superior strength to weight ratio and enhanced damage tolerance when compared to super alloy and monolithic ceramic materials. However, there are notable challenges when it comes to their successful implementation of these materials in hot-section aero-engine components, primarily stemming from their susceptibility to severe damage caused by solid particle erosion due to repeated particle impacts. Although extensive efforts have been dedicated in understanding erosion in CMCs, the majority of this research has been conducted under standard ambient conditions. Given the elevated temperature environments in which CMCs will ultimately operate, it becomes crucial to comprehend how high-temperature conditions impact the lifespan of CMCs subjected to high velocity particle impacts. Therefore, the primary focus of this research is on evaluating what parameters affect erosion behavior of oxide and non-oxide CMC at temperatures of 800°C and 1200°C with different velocity of 200m/s and 350m/s, respectively. On a different note, CMCs are prone to significant strength degradation upon material removal resulting from the repeated or cumulative impingement of solid particles. While erosion in ceramics and composites has been extensively studied, existing research may not be directly applicable to strength degradation caused due to repeated particle impacts on CMCs due to their more complex architecture and failure mechanisms at different operating temperatures. Therefore, second objective of this work is to investigate relationship between high temperature erosion behavior and strength degradation in several non-oxide and oxide-based CMCs and to evaluate erosion response caused by solid particle impacts under stress induced conditions involving fatigue and creep loading.

Committee: Gregory Morscher (Advisor); Simak Farhad (Committee Member); Manigandan Kannan (Committee Member); Craig Menzemer (Other); Jun Ye (Committee Member); Sergio D. Felicelli (Committee Chair); Qixin Zhou (Committee Member) Subjects: Mechanical Engineering

Doctor of Philosophy, The Ohio State University, 2022, Environmental Science

Accelerated erosion-induced topsoil loss threatens the productivity and sustainability of maize (Zea mays L.) cropping systems across the U.S. Corn Belt by adversely impacting soil health. The rehabilitation of soil health in eroded topsoil has been shown to improve with best management practices coupled with soil amendment application. The current study investigated the impact of simulated erosion and annual amendment application on soil health 20 years after establishment at two central Ohio sites (Waterman Farm: WF; Western Station: WS). Simulated erosion was employed in 1997 to create three incremental topsoil depths (TSD) (20 cm topsoil removed (TSD-0); 0 topsoil removed (TSD-1); 20 cm topsoil added (TSD-2). Annual application of three soil amendments (inorganic, synthetic N fertilizer (I); organic, compost manure amendment (O); no amendment (C)) were investigated for their ability to restore soil health in the surface 40 cm of these cropping systems. Increasing TSD resulted in more favorable physical, chemical, and biological soil health attributes primarily through enhanced soil structure, aggregation, water movement and storage, soil pH range, and SOC and soil N concentrations. The organic amendment proved most efficient in regenerating soil health at lower TSD levels and augmenting soil health in systems with greater TSD levels. Greater TSD usually resulted in greater C and N pools after two decades. However, this was variable at levels where greater TSD was present. Soils amended with the organic treatment always produced greater C and N stocks across both sites. The trends in SOC pools were TSD-1 ≥ TSD-2 > TSD-0 at the WF site and TSD-2 ≥ TSD-0 ≥ TSD-1 at the WS site. The trend in TN pools followed the same pattern as SOC pools at the WF site, but was TSD-2 ≥ TSD-1 ≥ TSD-0 at the WS site. Soils with greater TSD and those amended with the organic amendment were more resilient in the face of simulated rainfall and resulted in the smallest incurred losses of (open full item for complete abstract)

Committee: Rattan Lal (Advisor); Kristin Mercer (Committee Member); Steven Culman (Committee Member); Nicholas Basta (Committee Member) Subjects: Agriculture; Agronomy; Environmental Science; Soil Sciences; Water Resource Management

Master of Science (MS), Ohio University, 2022, Geography (Arts and Sciences)

The need for understanding the impacts of off-road vehicle (ORV) usage on trail systems is widely accepted, with few studies being conducted in humid climates and even fewer examining the impacts of unauthorized user-created ORV routes. This research examines cross-trail profile measurements along authorized ORV trails and unauthorized ORV routes in southeastern Ohio over a six-month period in order to calculate erosion rates and understand how each trail type behaves throughout the riding season. Measurements from the two trail types are compared to one another in varying combinations and between data collection periods. Spatial comparisons of soil compaction and soil texture are also analyzed. Results from statistical analyses showed that there is no significant difference in erosion rates between authorized and unauthorized trail segments despite apparent differences in eroded sediments between the two trail types. The highest measured erosion rates on authorized and unauthorized segments totaled 3.65 m3/yr and 15.95 m3/yr, respectively. Few sites were found to have significant geomorphic change along the trail surface during the six-month study period. Soil compaction values were found to be greater on the trail surface compared to the trail-adjacent forest in both trail types. Soil compaction of the trail surface was not found to be statistically different between the two trail types, nor were values from the trail-adjacent forest different between the trail types. The results of this study demonstrate the need for effective management efforts that focus management efforts not only on authorized ORV trails, but also the unauthorized routes that are associated in ORV trail systems.

Committee: Dorothy Sack (Advisor) Subjects: Environmental Geology; Environmental Management; Geography; Geomorphology