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 Title
 GPU ACCELERATED APPROACH TO NUMERICAL LINEAR ALGEBRA AND MATRIX ANALYSIS WITH CFD APPLICATIONS.
 Creator

Phillips, Adam, Shivamoggi, Bhimsen, University of Central Florida
 Abstract / Description

A GPU accelerated approach to numerical linear algebra and matrix analysis with CFD applications is presented. The works objectives are to (1) develop stable and efficient algorithms utilizing multiple NVIDIA GPUs with CUDA to accelerate common matrix computations, (2) optimize these algorithms through CPU/GPU memory allocation, GPU kernel development, CPU/GPU communication, data transfer and bandwidth control to (3) develop parallel CFD applications for NavierStokes and Lattice Boltzmann...
Show moreA GPU accelerated approach to numerical linear algebra and matrix analysis with CFD applications is presented. The works objectives are to (1) develop stable and efficient algorithms utilizing multiple NVIDIA GPUs with CUDA to accelerate common matrix computations, (2) optimize these algorithms through CPU/GPU memory allocation, GPU kernel development, CPU/GPU communication, data transfer and bandwidth control to (3) develop parallel CFD applications for NavierStokes and Lattice Boltzmann analysis methods. Special consideration will be given to performing the linear algebra algorithms under certain matrix types (banded, dense, diagonal, sparse, symmetric and triangular). Benchmarks are performed for all analyses with baseline CPU times being determined to find speedup factors and measure computational capability of the GPU accelerated algorithms. The GPU implemented algorithms used in this work along with the optimization techniques performed are measured against preexisting work and test matrices available in the NIST Matrix Market. CFD analysis looked to strengthen the assessment of this work by providing a direct engineering application to analysis that would benefit from matrix optimization techniques and accelerated algorithms. Overall, this work desired to develop optimization for selected linear algebra and matrix computations performed with modern GPU architectures and CUDA developer which were applied directly to mathematical and engineering applications through CFD analysis.
Show less  Date Issued
 2014
 Identifier
 CFH0004605, ucf:45287
 Format
 Document (PDF)
 PURL
 http://purl.flvc.org/ucf/fd/CFH0004605
 Title
 IMPULSE FORMULATIONS OF THE EULER EQUATIONS FOR INCOMPRESSIBLE AND COMPRESSIBLE FLUIDS.
 Creator

Pareja, Victor, Shivamoggi, Bhimsen, University of Central Florida
 Abstract / Description

The purpose of this paper is to consider the impulse formulations of the Euler equations for incompressible and compressible fluids. Different gauges are considered. In particular, the Kuz'min gauge provides an interesting case as it allows the fluid impulse velocity to describe the evolution of material surface elements. This result affords interesting physical interpretations of the Kuz'min invariant. Some exact solutions in the impulse formulation are studied. Finally,...
Show moreThe purpose of this paper is to consider the impulse formulations of the Euler equations for incompressible and compressible fluids. Different gauges are considered. In particular, the Kuz'min gauge provides an interesting case as it allows the fluid impulse velocity to describe the evolution of material surface elements. This result affords interesting physical interpretations of the Kuz'min invariant. Some exact solutions in the impulse formulation are studied. Finally, generalizations to compressible fluids are considered as an extension of these results. The arrangement of the paper is as follows: in the first chapter we will give a brief explanation on the importance of the study of fluid impulse. In chapters two and three we will derive the Kuz'min, E & Liu, Maddocks & Pego and the Zero gauges for the evolution equation of the impulse density, as well as their properties. The first three of these gauges have been named after their authors. Chapter four will study two exact solutions in the impulse formulation. Physical interpretations are examined in chapter five. In chapter six, we will begin with the generalization to the compressible case for the Kuz'min gauge, based on Shivamoggi et al. (2007), and we will derive similar results for the remaining gauges. In Chapter seven we will examine physical interpretations for the compressible case.
Show less  Date Issued
 2007
 Identifier
 CFE0001907, ucf:47492
 Format
 Document (PDF)
 PURL
 http://purl.flvc.org/ucf/fd/CFE0001907
 Title
 Terahertz Emission from the Intrinsic Josephson Junctions of HighSymmetry ThermallyManaged Bi2Sr2CaCu2O8+d Annular Microstrip Antennas.
 Creator

Bonnough, Sheila, Klemm, Richard, Peale, Robert, Shivamoggi, Bhimsen, University of Central Florida
 Abstract / Description

The intrinsic Josephson junctions in the high transition temperature superconductor Bi2Sr2CaCu2O8+? (BSCCO) have shown great potential for oscillators emitting in the terahertz frequency. The radiation frequency satisfies the conditions for both the ac Josephson effect and for a mesa cavity resonance mode. The observed angular dependence of the emissions from some mesa imply that the ac Josephson effect plays the primary role in a dual source radiation mechanism. But the integrated emission...
Show moreThe intrinsic Josephson junctions in the high transition temperature superconductor Bi2Sr2CaCu2O8+? (BSCCO) have shown great potential for oscillators emitting in the terahertz frequency. The radiation frequency satisfies the conditions for both the ac Josephson effect and for a mesa cavity resonance mode. The observed angular dependence of the emissions from some mesa imply that the ac Josephson effect plays the primary role in a dual source radiation mechanism. But the integrated emission power had generally been significantly below the 1 mW level suitable for many applications. This output power can be enhanced by a suitable design of an array of suitably shaped mesas that are all within a wavelength of each other so that their combined output is coherent. One such tightly packed array consists of concentric annuli. Here we calculate the angularly independent modes of thin annular microstrip antennas, with the ratio of the inner to the outer radii varying from 0.1 to 0.9. We then calculate the angular distribution of the emission power arising from the annular cavity modes and from the uniform ac Josephson current source at the frequencies of the cavity modes. We also calculate the five leading wavefunctions with the lowest order angular dependence for those annuli.
Show less  Date Issued
 2018
 Identifier
 CFE0007314, ucf:52137
 Format
 Document (PDF)
 PURL
 http://purl.flvc.org/ucf/fd/CFE0007314
 Title
 Detailed Understanding of Flow, Heat Transfer, and Pressure Drop Behavior in a Square Channel With 45 Deg Ribs.
 Creator

Ahmed, Lumaya, Kapat, Jayanta, Gordon, Ali, Ahmed, Kareem, Shivamoggi, Bhimsen, University of Central Florida
 Abstract / Description

Internal Duct Cooling (IDC) with rib turbulators is one of the common cooling techniques applied inside the turbine airfoils. It is very important for the gas turbine industry to design and develop an optimized cooling channel that maximizes the amount of heat removed, while simultaneously minimizing the pressure drop for a target overall cooling effectiveness. Angled ribs perform superior to the transverse ribs due to additional secondary flow associated with them. However, they result in a...
Show moreInternal Duct Cooling (IDC) with rib turbulators is one of the common cooling techniques applied inside the turbine airfoils. It is very important for the gas turbine industry to design and develop an optimized cooling channel that maximizes the amount of heat removed, while simultaneously minimizing the pressure drop for a target overall cooling effectiveness. Angled ribs perform superior to the transverse ribs due to additional secondary flow associated with them. However, they result in a highly nonhomogenous heat transfer distribution, which is a manifestation of the complex, turbulent flow field inside the channel. It is very important to comprehend the secondary flow physics to characterize the heat transfer distribution in such angled ribbed channels. Additionally, due to the manufacturing constraint, the gas turbine industry encounters a challenge to make ribs edge sharp and results in ribs with rounded edges. The one of the main objectives of the present study is to provide a fundamental understanding of the flow physics on the heat transfer and pressure drop behavior in 45(&)deg; ribbed channels both with sharp and roundededge ribs. It is found that the secondary flow has a significant effect on the heat transfer behavior for both types of ribs. There is a great need of highfidelity PIV flow field data in the interrib space for an angled ribbed channel which can be used for CFD validation, especially for LES. The current study provides benchmarking flow field data in the interrib space in a square channel with 45(&)deg; ribs using stereoscopic PIV technique. Besides the experiments, numerical studies were also conducted by using LES and different RANS models. The LES results show an excellent prediction capability for aerothermal behavior in such channels. However, the prediction capability of RANS models is found to be inconsistent for different rib configurations and flow conditions.
Show less  Date Issued
 2018
 Identifier
 CFE0007302, ucf:52171
 Format
 Document (PDF)
 PURL
 http://purl.flvc.org/ucf/fd/CFE0007302
 Title
 Multiphase Flow Modeling of Molten Metal Atomization at High Gas Pressure.
 Creator

Hanthanan Arachchilage, Kalpana, Kumar, Ranganathan, Sohn, Yongho, Kassab, Alain, Shivamoggi, Bhimsen, University of Central Florida
 Abstract / Description

The highpressure gas atomization is well known as one of the best powder manufacturing processes due to its controllability over powder size distribution. However, with the continuous improvement of new alloys, optimizing the operating parameters to maximize the yield is costly and timeconsuming. Therefore, it is essential to understand the highpressure gas atomization process and the effects of different operational parameters on the powder size distribution.Twophase numerical...
Show moreThe highpressure gas atomization is well known as one of the best powder manufacturing processes due to its controllability over powder size distribution. However, with the continuous improvement of new alloys, optimizing the operating parameters to maximize the yield is costly and timeconsuming. Therefore, it is essential to understand the highpressure gas atomization process and the effects of different operational parameters on the powder size distribution.Twophase numerical simulations are performed to capture the interfacial dynamic during the atomization process and to obtain the effects of gas pressure, melt flow rate, and thermophysical properties of atomizing gas and the molten metal. The Volume of Fluid (VOF) model is used to capture the meltgas interface, and inhouse postprocessing code is developed to obtain the droplet size distributions. Threedimensional geometry of an annularslit closecoupled gas atomizer is utilized to investigate the primary atomization process. The current grid resolution is sufficient forcapturing primary atomization and some characteristics of the secondary atomization, but it is not adequate to capture all the length scales in secondary atomization. Qualitative comparisons of the cumulative volume graphs indicate that this numerical approach is capable of capturing the trends in the atomization process as in the experiments. It is found that a combination of several interfacial instabilities governs the atomization process. Simulations corresponding to different gas pressures show that the atomizationcharacteristics remain unchanged irrespective of the gas pressure. However, it is found that the rate of the evolution and the effectiveness of the atomization process increases with the gas pressure. Three melts (aluminum, steel, and an artificial material with intermediate thermophysical properties) are used to investigate the effects of the molten metal properties and found that the rate of the atomization process decreases with increasing melt density, and the yield of the atomized powder is seen to increase. The flow characteristics remain unchanged for all three melts. The melt flow is strongly correlated with flow characteristics and interfacial instability.
Show less  Date Issued
 2019
 Identifier
 CFE0007814, ucf:52342
 Format
 Document (PDF)
 PURL
 http://purl.flvc.org/ucf/fd/CFE0007814
 Title
 The Relativistic Harmonic Oscillator and the Generalization of Lewis' Invariant.
 Creator

Reinhart, Daniel, Shivamoggi, Bhimsen, Kokoouline, Viatcheslav, Dove, Adrienne, University of Central Florida
 Abstract / Description

In this thesis, we determine an asymptotic solution for the one dimensional relativistic harmonicoscillator using multiple scale analysis and relate the resulting invariant to Lewis' invariant. Wethen generalize the equations leading to Lewis' invariant so they are relativistically correct. Nextwe attempt to find an asymptotic solution for the general equations by making simplifying assumptionson the parameter characterizing the adiabatic nature of the system. The first term inthe series for...
Show moreIn this thesis, we determine an asymptotic solution for the one dimensional relativistic harmonicoscillator using multiple scale analysis and relate the resulting invariant to Lewis' invariant. Wethen generalize the equations leading to Lewis' invariant so they are relativistically correct. Nextwe attempt to find an asymptotic solution for the general equations by making simplifying assumptionson the parameter characterizing the adiabatic nature of the system. The first term inthe series for Lewis' invariant corresponds to the adiabatic invariant for systems whose frequencyvaries slowly. For the relativistic case we find a new conserved quantity and seek to explore itsinterpretation.iii
Show less  Date Issued
 2019
 Identifier
 CFE0007712, ucf:52434
 Format
 Document (PDF)
 PURL
 http://purl.flvc.org/ucf/fd/CFE0007712
 Title
 On Hall Magnetohydrodynamics: Xtype Neutral Point and Parker Problem.
 Creator

Reger, Kyle, Shivamoggi, Bhimsen, Rollins, David, Eastes, Richard, University of Central Florida
 Abstract / Description

The framework for the Hall magnetohydrodynamic (MHD) model for plasma physics is built up from kinetic theory and used to analytically solve problems of interest in the field. The Hall MHD model describes fast magnetic reconnection processes in space and laboratory plasmas. Specifically, the magnetic reconnection process at an Xtype neutral point, where current sheets form and store enormous amounts of magnetic energy which is later released as magnetic storms when the sheets break up, is...
Show moreThe framework for the Hall magnetohydrodynamic (MHD) model for plasma physics is built up from kinetic theory and used to analytically solve problems of interest in the field. The Hall MHD model describes fast magnetic reconnection processes in space and laboratory plasmas. Specifically, the magnetic reconnection process at an Xtype neutral point, where current sheets form and store enormous amounts of magnetic energy which is later released as magnetic storms when the sheets break up, is investigated. The phenomena of magnetic flux pileup driving the merging of antiparallel magnetic fields at an ion stagnationpoint flow in a thin current sheet, called the Parker problem, also receives rigorous mathematical analysis.
Show less  Date Issued
 2012
 Identifier
 CFE0004428, ucf:49345
 Format
 Document (PDF)
 PURL
 http://purl.flvc.org/ucf/fd/CFE0004428
 Title
 High Energy, High Average Power, Picosecond Laser Systems to Drive FewCycle OPCPA.
 Creator

Vaupel, Andreas, Richardson, Martin, Delfyett, Peter, Schulzgen, Axel, Shivamoggi, Bhimsen, University of Central Florida
 Abstract / Description

The invention of chirpedpulse amplification (CPA) in 1985 led to a tremendous increase in obtainable laser pulse peak intensities. Since then, several tabletop, Ti:sapphirebased CPA systems exceeding the 100 TWlevel with more than 10 W average power have been developed and several systems are now commercially available. Over the last decade, the complementary technology of optical parametric chirpedpulse amplification (OPCPA) has improved in its performance to a competitive level. OPCPA...
Show moreThe invention of chirpedpulse amplification (CPA) in 1985 led to a tremendous increase in obtainable laser pulse peak intensities. Since then, several tabletop, Ti:sapphirebased CPA systems exceeding the 100 TWlevel with more than 10 W average power have been developed and several systems are now commercially available. Over the last decade, the complementary technology of optical parametric chirpedpulse amplification (OPCPA) has improved in its performance to a competitive level. OPCPA allows direct amplification of an almostoctave spanning bandwidth supporting fewcycle pulse durations at center wavelengths ranging from the visible to the midIR. The current record in peak power from a tabletop OPCPA is 16 TW and the current record average power is 22 W. High energy, fewcycle pulses with stabilized carrierenvelope phase (CEP) are desired for applications such as highharmonic generation (HHG) enabling attoscience and the generation keVphoton bursts.This dissertation conceptually, numerically and experimentally describes essential aspects of fewcycle OPCPA, and the associated pump beam generation. The main part of the conducted research was directed towards the fewcycle OPCPA facility developed in the Laser Plasma Laboratory at CREOL (University of Central Florida, USA) termed HERACLES. This facility was designed to generate fewcycle pulses in the visible with mJlevel pulse energy, Wlevel average power and more than 100 GW peak power. Major parts of the implementation of the HERACLES facility are presented.The pump generation beam of the HERACLES system has been improved in terms of pulse energy, average power and stability over the last years. It is based on diodepumped, solidstate amplifiers with picosecond duration and experimental investigations are presented in detail. A robust system has been implemented producing mJlevel pulse energies with ~100 ps pulse duration at kHz repetition rates. Scaling of this system to high power ((>)30 W) and high peak power (50MWlevel) as well as ultrahigh pulse energy ((>)160 mJ) is presented. The latter investigation resulted in the design of an ultrahigh energy system for OPCPA pumping. Following this, a new OPCPA facility was designed termed PhaSTHEUS, which is anticipated to reach ultrahigh intensities.Another research effort was conducted at CELIA (Univerist(&)#233; de Bordeaux 1, France) and aimed towards a previously unexplored operational regime of OPCPA with ultrahigh repetition rates (10 MHz) and high average power. A supercontinuum seed beam generation has been established with an output ranging from 1.3 to 1.9 ?m and few ps duration. The pump beam generation has been implemented based on rodtype fiber amplifiers producing more than 37 W average power and 370 kW peak power. The utility of this system as an OPCPA pump laser is presented along with the OPA design.The discussed systems operate in radically different regimes in terms of peak power, average power, and repetition rate. The anticipated OPCPA systems with fewcycle duration enable a wide range of novel experimental studies in attoscience, ultrafast materials processing, filamentation, LIBS and coherent control.
Show less  Date Issued
 2013
 Identifier
 CFE0004952, ucf:49570
 Format
 Document (PDF)
 PURL
 http://purl.flvc.org/ucf/fd/CFE0004952
 Title
 Numerical Study of Interfacial flow using Algebraic Coupled Level SetVolume of Fluid (ACLSVOF) Method.
 Creator

Haghshenas, Majid, Kumar, Ranganathan, Das, Tuhin, Ahmed, Kareem, Shivamoggi, Bhimsen, University of Central Florida
 Abstract / Description

Solving interfacial flows numerically has been a challenge due to the lack of sharpness and the presence of spurious currents at the interface. Two methods, Algebraic Coupled Level SetVolume of Fluid (ACLSVOF) method and Ghost Fluid Method (GFM) have been developed in the finite volume framework and employed in several interfacial flows such as RayleighTaylor instability, rising bubble, impinging droplet and crossflow oil plume. In the static droplet simulation, ACLSVOF substantially...
Show moreSolving interfacial flows numerically has been a challenge due to the lack of sharpness and the presence of spurious currents at the interface. Two methods, Algebraic Coupled Level SetVolume of Fluid (ACLSVOF) method and Ghost Fluid Method (GFM) have been developed in the finite volume framework and employed in several interfacial flows such as RayleighTaylor instability, rising bubble, impinging droplet and crossflow oil plume. In the static droplet simulation, ACLSVOF substantially reduces the spurious currents. The capillary wave relaxation shows that this method delivers results comparable to those of more rigorous methods such as Front Tracking methods for fine grids. The results for the other interfacial flows also compared well with the experimental results. Next, interfacial forces are implemented by enlisting the finite volume discretization of Ghost Fluid Method. To assess the ACLSVOF/GFM performance, four cases are studied. In the case of the static droplet in suspension, the combined ACLSVOF/GFM produces a sharp and accurate pressure jump compared to the traditional CSF (continuum surface force) implementation. For the linear twolayer shear flow, GFM sharp treatment of the viscosity captured the velocity gradient across the interface. For a gaseous bubble rising in a viscous fluid, GFM outperforms CSF by almost 10%. Also, a Decoupled Pressure ACLSVOF/GFM method (DPM) has been developed which separates pressure into two pressure components, one accounting for interfacial forces such as surface tension and another representing the rest of flow pressure. It is proven that the DPM implementation results in more efficiency in PISO (Pressure Implicit with Splitting of Operators) loop. A twophase solver is used to study buoyant oil discharge in quiescent and crossflow ambient. Different modes of breakup including dripping, jetting (axisymmetric and asymmetric) and atomization for crossflow oil jet are captured.
Show less  Date Issued
 2018
 Identifier
 CFE0007570, ucf:52582
 Format
 Document (PDF)
 PURL
 http://purl.flvc.org/ucf/fd/CFE0007570
 Title
 Enhanced Ablation by Femtosecond and Nanoseond Laser Pulses.
 Creator

Kerrigan, Haley, Richardson, Martin, Baudelet, Matthieu, Shivamoggi, Bhimsen, University of Central Florida
 Abstract / Description

Laser ablation of GaAs by a combination of femtosecond and nanosecond pulses is investigated as a means of enhancing material removal by a femtosecond pulse in the filamentation intensity regime. We demonstrate for the first time increased ablation of GaAs by ultrafast laser pulse plasmas augmented by nanosecond pulse radiation from a secondary laser. Material removal during laser ablation is a complex process that occurs via multiple mechanisms over several timescales. Due to different pulse...
Show moreLaser ablation of GaAs by a combination of femtosecond and nanosecond pulses is investigated as a means of enhancing material removal by a femtosecond pulse in the filamentation intensity regime. We demonstrate for the first time increased ablation of GaAs by ultrafast laser pulse plasmas augmented by nanosecond pulse radiation from a secondary laser. Material removal during laser ablation is a complex process that occurs via multiple mechanisms over several timescales. Due to different pulse durations, ablation by femtosecond and nanosecond pulses are dominated by different mechanisms. Ablation can be enhanced by optimally combining a femtosecond and nanosecond pulse in time. In this work, the craters generated by combinations of pulses are investigated for interpulse delays ranging from 50ns to +1?s, with the fs pulse preceding the ns pulse corresponding to a positive delay. The Ti:Sapph MultiTerawatt Femtosecond Laser (MTFL) in the Laser Plasma Laboratory (LPL) provides 50fs pulses at 800nm with intensities of 1014W/cm^2 at the sample. An Nd:YAG laser (Quantel CFR200) provides 8ns pulses at 1064nm with intensities of 109W/cm^2. Crater profilometry with whitelight interferometry and optical microscopy determine the structure and surface features of the craters and the volume of material removed. Ultrafast shadowgraphy of the ejected plasma provides insight to the dualpulse ablation dynamics. SedovTaylor analysis of the generated shockwave reveals the energy coupled to the sample or preceding plasma. It was found that interpulse delays between +40 and +200ns yielded craters 2.5x greater in volume than that of the femtosecond pulse alone, with a maximum enhancement of 2.7x at +100ns. Shadowgraphy of 40 to +40ns delays revealed that enhancement occurs when the nanosecond pulse couples to plasma generated by the fs pulse. This work provides a possible means of enhancing ablation by femtosecond filaments, which propagate long distances with clamped intensity, advancing longrange standoff ablation
Show less  Date Issued
 2017
 Identifier
 CFE0006889, ucf:51734
 Format
 Document (PDF)
 PURL
 http://purl.flvc.org/ucf/fd/CFE0006889
 Title
 Dynamical Invariants and the Fluid Impulse in Plasma Models.
 Creator

Michalak, Martin, Shivamoggi, Bhimsen, Mohapatra, Ram, Brennan, Joseph, Eastes, Richard, University of Central Florida
 Abstract / Description

Much progress has been made in understanding of plasmas through the use of the MHD equations and newer models such as Hall MHD and electron MHD. As with most equations of fluid behavior, these equations are nonlinear, and no general solutions can be found. The use of invariant structures allows limited predictions of fluid behavior without requiring a full solution of the underlying equations. The use of gauge transformation can allow the creation of new invariants, while differential...
Show moreMuch progress has been made in understanding of plasmas through the use of the MHD equations and newer models such as Hall MHD and electron MHD. As with most equations of fluid behavior, these equations are nonlinear, and no general solutions can be found. The use of invariant structures allows limited predictions of fluid behavior without requiring a full solution of the underlying equations. The use of gauge transformation can allow the creation of new invariants, while differential geometry offers useful tools for constructing additional invariants from those that are already known. Using these techniques, new geometric, integral and topological invariants are constructed for Hall and electron MHD models. Both compressible and incompressible models are considered, where applicable. An application of topological invariants to magnetic reconnection is provided. Finally, a particular geometric invariant, which can be interpreted as the fluid impulse density, is studied in greater detail, its nature and invariance in plasma models is demonstrated, and its behavior is predicted in particular geometries under different models.
Show less  Date Issued
 2013
 Identifier
 CFE0005382, ucf:50442
 Format
 Document (PDF)
 PURL
 http://purl.flvc.org/ucf/fd/CFE0005382
 Title
 Mathematical Foundations of Adaptive Quantum Processing.
 Creator

Bonior, Daniel, Mucciolo, Eduardo, Martin, Keye, Argenti, Luca, Shivamoggi, Bhimsen, Marinescu, Dan, University of Central Florida
 Abstract / Description

Quantum information has the potential to revolutionize the way we store, process, transfer and acquire information [1,14,15,21,37]. In particular, quantum information offers exciting new approaches to secure communication, computation and sensing. However, in order to realize such technologies, we must first understand the effect that environmental noise has on a quantum system. This dissertation builds upon recent studies that have explored the underlying structure of quantum information and...
Show moreQuantum information has the potential to revolutionize the way we store, process, transfer and acquire information [1,14,15,21,37]. In particular, quantum information offers exciting new approaches to secure communication, computation and sensing. However, in order to realize such technologies, we must first understand the effect that environmental noise has on a quantum system. This dissertation builds upon recent studies that have explored the underlying structure of quantum information and the effects of qubit channels in quantum communication protocols.This work is divided into five main chapters, with Chapter 1 being a brief introduction to quantum information. We then begin Chapter 2 by defining the error function for our qubit communication protocols. From there we explore the properties of our error functions and the topological space that they form. In Chapter 3 we consider the newly patented process Adaptive Quantum Information Processing, patent number US9838141 B2; originally outlined by Martin in [23]. We restate the adaptive scheme and exemplify its application through the Prepare and Send Protocol and Quantum Key Distribution. Applying our results from Chapter 2, we obtain an expression for the adaptability of unital channels in these two protocols and classify the channels that admit the most improvement. We dedicate Chapter 4 to the derivation of gravitational noise, and show that in certain circumstances gravity results in a channel that can be maximally improved in Adaptive QKD [3,14,16]. Lastly, we study the set of error functions through the lens of domain theory. Domain theory is a subset of mathematics that was developed in order to rigorously formalize computations. The first four chapters are all consequences of past discoveries in the mathematical structure of quantum channels. In Chapter 5 we characterize the set of error functions through domain theory, extending the mathematical foundations of quantum information. [12,18,20, 22, 23,25].
Show less  Date Issued
 2018
 Identifier
 CFE0007313, ucf:52124
 Format
 Document (PDF)
 PURL
 http://purl.flvc.org/ucf/fd/CFE0007313
 Title
 Effect of Nonclassical Optical Turbulence on a Propagating Laser Beam.
 Creator

Beason, Melissa, Phillips, Ronald, Atia, George, Richardson, Martin, Andrews, Larry, Shivamoggi, Bhimsen, University of Central Florida
 Abstract / Description

Theory developed for the propagation of a laser beam through optical turbulence generally assumes that the turbulence is both homogeneous and isotropic and that the associated spectrum follows the classical Kolmogorov spectral power law of . If the atmosphere deviates from these assumptions, beam statistics such as mean intensity, correlation, and scintillation index could vary significantly from mathematical predictions. This work considers the effect of nonclassical turbulence on a...
Show moreTheory developed for the propagation of a laser beam through optical turbulence generally assumes that the turbulence is both homogeneous and isotropic and that the associated spectrum follows the classical Kolmogorov spectral power law of . If the atmosphere deviates from these assumptions, beam statistics such as mean intensity, correlation, and scintillation index could vary significantly from mathematical predictions. This work considers the effect of nonclassical turbulence on a propagated beam. Namely, anisotropy of the turbulence and a power law that deviates from . A mathematical model is developed for the scintillation index of a Gaussian beam propagated through nonclassical turbulence and theory is extended for the covariance function of intensity of a plane wave propagated through nonclassical turbulence. Multiple experiments over a concrete runway and a grass range verify the presence of turbulence which varies between isotropy and anisotropy. Data is taken throughout the day and the evolution of optical turbulence is considered. Also, irradiance fluctuation data taken in May 2018 over a concrete runway and July 2018 over a grass range indicate an additional beam shaping effect. A simplistic mathematical model was formulated which reproduced the measured behavior of contours of equal mean intensity and scintillation index.?
Show less  Date Issued
 2018
 Identifier
 CFE0007310, ucf:52646
 Format
 Document (PDF)
 PURL
 http://purl.flvc.org/ucf/fd/CFE0007310
 Title
 Prediction of survival of early stages lung cancer patients based on ER beta cellular expressions and epidemiological data.
 Creator

Martinenko, Evgeny, Shivamoggi, Bhimsen, Chow, Lee, Peale, Robert, Brandenburg, John, University of Central Florida
 Abstract / Description

We attempted a mathematical model for expected prognosis of lung cancer patients based ona multivariate analysis of the values of ERinteracting proteins (ERbeta) and a membranebound, glycosylated phosphoprotein MUC1), and patients clinical data recorded at the timeof initial surgery. We demonstrate that, even with the limited sample size available to use,combination of clinical and biochemical data (in particular, associated with ERbeta andMUC1) allows to predict survival of lung cancer...
Show moreWe attempted a mathematical model for expected prognosis of lung cancer patients based ona multivariate analysis of the values of ERinteracting proteins (ERbeta) and a membranebound, glycosylated phosphoprotein MUC1), and patients clinical data recorded at the timeof initial surgery. We demonstrate that, even with the limited sample size available to use,combination of clinical and biochemical data (in particular, associated with ERbeta andMUC1) allows to predict survival of lung cancer patients with about 80% accuracy whileprediction on the basis of clinical data only gives about 70% accuracy. The present work canbe viewed as a pilot study on the subject: since results conrm that ERinteracting proteinsindeed inuence lung cancer patients' survival, more data is currently being collected.
Show less  Date Issued
 2011
 Identifier
 CFE0004134, ucf:49120
 Format
 Document (PDF)
 PURL
 http://purl.flvc.org/ucf/fd/CFE0004134
 Title
 Numerical Simulation of Conventional Fuels and Biofuels Dispersion and Vaporization Process in Coflow and Crossflow Premixers.
 Creator

Gu, Xin, Kumar, Ranganathan, Basu, Saptarshi, Kapat, Jayanta, Chow, Louis, Shivamoggi, Bhimsen, University of Central Florida
 Abstract / Description

In order to follow increasingly strict regulation of pollutant emissions, a new concept of Lean Premixed prevaporized (LPP) combustion has been proposed for turbines. In LPP combustion, controlled atomization, dispersion and vaporization of different types of liquid fuel in the premixer are the key factors required to stabilize the combustion process and improve the efficiency. A numerical study is conducted for the fundamental understanding of the liquid fuel dispersion and vaporization...
Show moreIn order to follow increasingly strict regulation of pollutant emissions, a new concept of Lean Premixed prevaporized (LPP) combustion has been proposed for turbines. In LPP combustion, controlled atomization, dispersion and vaporization of different types of liquid fuel in the premixer are the key factors required to stabilize the combustion process and improve the efficiency. A numerical study is conducted for the fundamental understanding of the liquid fuel dispersion and vaporization process in premixers using both crossflow and coflow injection methods. First, the vaporization model is validated by comparing the numerical data to existing experiments of single droplet vaporization under both low and high convective air temperatures. Next, the dispersion and vaporization process for biofuels and conventional fuels injected transversely into a typical simplified version of rectangular premixer are simulated and results are analyzed with respect to vaporization performance, degree of mixedness and homogeneity. Finally, collision model has been incorporated to predict more realistic vaporization performance. Four fuels, Ethanol, Rapeseed Methyl Esters (RME), gasoline and jetA have been investigated. For monodisperse spray with no collision model, the droplet diameter reduction and surface temperature rise were found to be strongly dependent on the fuel properties. The diameter histogram near the premixer exit showed a wide droplet diameter distribution for all the fuels. In general, preheating of the fuels before injection improved the vaporization performance. An improvement in the drag model with Stefan flow correction showed that a low speed injection and high cone angle improved performance. All fuels achieved complete vaporization under a spray cone angle of 140(&)deg;. In general, it was found that crossflow injection achieved better vaporization performance than coflow injection. A correlation is derived for jetA's total vaporization performance as a function of nondimensional inlet air temperature and fuel/air momentum flux ratio. This is achieved by curvefitting the simulated results for a broad range of inlet air temperatures and fuel/air momentum flux ratios. The collision model, based on notimecounter method (NTC) proposed by Schmidt and Rutland, was implemented to replace O'Rourke's collision algorithm to improve the results such that the unphysical numerical artifact in a Cartesian grid was removed and the results were found to be gridindependent. The dispersion and vaporization processes for liquid fuel sprays were simulated in a cylindrical premixer using coflow injection method. Results for jetA and Rapeseed Methyl Esters (RME) showed acceptable grid independence. At relatively low spray cone angle and injection velocity, it was found that the collision effect on the average droplet size and the vaporization performance were very high due to relatively high coalescence rate induced by droplet collisions. It was also found that the vaporization performance and the level of homogeneity of fuelair mixture could be significantly improved when the dispersion level is high, which can be achieved by increasing the spray cone angle and injection velocity. In order to compare the performance between coflow and crossflow injection methods, the fuels were injected at an angle of 40(&)deg; with respect to the stream wise direction to avoid impacting on the wall. The crossflow injection achieved similar vaporization performance as coflow because a higher coalescence rate induced by droplet collisions cancelled off its higher heat transfer efficiency between two phases for crossflow injections.
Show less  Date Issued
 2012
 Identifier
 CFE0004192, ucf:49004
 Format
 Document (PDF)
 PURL
 http://purl.flvc.org/ucf/fd/CFE0004192
 Title
 Evaporation, Precipitation Dynamics and Instability of Acoustically Levitated Functional Droplets.
 Creator

Saha, Abhishek, Kumar, Ranganathan, Basu, Saptarshi, Kapat, Jayanta, Deng, Weiwei, Shivamoggi, Bhimsen, University of Central Florida
 Abstract / Description

Evaporation of pure and binary liquid droplets is of interest in thermal sprays and spray drying of food, ceramics and pharmaceutical products. Understanding the rate of heat and mass transfer in any drying process is important not only to enhance evaporation rate or vaporgas mixing, but also to predict and control the final morphology and microstructure of the precipitates. Acoustic levitation is an alternative method to study micronsized droplets without wall effects, which eliminates...
Show moreEvaporation of pure and binary liquid droplets is of interest in thermal sprays and spray drying of food, ceramics and pharmaceutical products. Understanding the rate of heat and mass transfer in any drying process is important not only to enhance evaporation rate or vaporgas mixing, but also to predict and control the final morphology and microstructure of the precipitates. Acoustic levitation is an alternative method to study micronsized droplets without wall effects, which eliminates chemical and thermal contamination with surfaces. This work uses an ultrasonic levitation technique to investigate the vaporization dynamics under radiative heating, with focus on evaporation characteristics, precipitation kinetics, particle agglomeration, structure formation and droplet stability. Timescale and temperature scales are developed to compare convective heating in actual sprays and radiative heating in the current experiments. These relationships show that simple experiments can be conducted in a levitator to extrapolate information in realistic convective environments in spray drying. The effect of acoustic streaming, droplet size and liquid properties on internal flow is important to understand as the heat and mass transfer and particle motion within the droplet is significantly controlled by internal motion. Therefore, the droplet internal flow is characterized by Particle Image Velocimetry for different dropsize and viscosity. Nanosuspension droplets suspended under levitation show preferential accumulation and agglomeration kinetics. Under certain conditions, they form bowl shaped structures upon complete evaporation. At higher concentrations, this initial bowl shaped structure morphs into a ring structure. Nanoparticle migration due to internal recirculation forms a density stratification, the location of which depends on initial particle concentration. The time scale of density stratification is similar to that of perikineticdriven agglomeration of particle flocculation. The density stratification ultimately leads to force imbalance leading to a unique bowlshaped structure. Chemically active precursor droplet under acoustic levitation shows events such as vaporization, precipitation and chemical reaction leading to nanoceria formation with a porous morphology. The cerium nitrate droplet undergoes phase and shape changes throughout the vaporization process followed by formation of precipitate. Exsitu analyses using TEM and SEM reveal highly porous morphology with trapped gas pockets and nanoceria crystalline structures at 70 degree C. Inhomogeneity in acoustic pressure around the heated droplet can induce thermal instability. Short wavelength (KelvinHelmholtz) instability for diesel and biodiesel droplets triggers this secondary atomization, which occurs due to relative velocity between liquid and gas phase at the droplet equator. On the other hand, liquids such as Kerosene and FC43 show uncontrollable stretching followed by a catastrophic breakup due to reduction in surface tension and viscosity coupled with inhomogeneity of pressure around the droplet. Finally, a scaling analysis has been established between vaporizing droplets in a convective and radiative environment. The transient temperature normalized by the respective scales exhibits a unified profile for both modes of heating. The analysis allows for the prediction of required laser flux in the levitator experiments to show its equivalence in a corresponding heated gas stream. The theoretical equivalence shows good agreement with experiments for a range of droplet sizes.
Show less  Date Issued
 2012
 Identifier
 CFE0004436, ucf:49346
 Format
 Document (PDF)
 PURL
 http://purl.flvc.org/ucf/fd/CFE0004436
 Title
 Experimental and Numerical Study of Endwall Film Cooling.
 Creator

Mahadevan, Srikrishna, Kapat, Jayanta, Verma, Shashi, Vasu Sumathi, Subith, Ahmed, Kareem, Shivamoggi, Bhimsen, University of Central Florida
 Abstract / Description

This research work investigates the thermal performance of a filmcooled gas turbine endwall under two different mainstream flow conditions. In the first part of the research investigation, the effect of unsteady passing wakes on a filmcooled pitchwisecurved surface (representing an endwall without airfoils) was experimentally studied for heat transfer characteristics on a timeaveraged basis. The temperature sensitive paint technique was used to obtain the local temperatures on the test...
Show moreThis research work investigates the thermal performance of a filmcooled gas turbine endwall under two different mainstream flow conditions. In the first part of the research investigation, the effect of unsteady passing wakes on a filmcooled pitchwisecurved surface (representing an endwall without airfoils) was experimentally studied for heat transfer characteristics on a timeaveraged basis. The temperature sensitive paint technique was used to obtain the local temperatures on the test surface. The required heat flux input was provided using foil heaters. Discrete film injection was implemented on the test surface using cylindrical holes with a streamwise inclination angle of 35? and no compound angle relative to the mean approach velocity vector. The passing wakes increased the heat transfer coefficients at both the wake passing frequencies that were experimented. Due to the increasing film cooling jet turbulence and strong jetmainstream interaction at higher blowing ratios, the heat transfer coefficients were amplified. A combination of film injection and unsteady passing wakes resulted in a maximum pitchaveraged and centerline heat transfer augmentation of ? 28% and 31.7% relative to the no wake and no film injection case. The second part of the research study involves an experimental and numerical analysis of secondary flow and coolant film interaction in a high subsonic annular cascade with a maximum isentropic throat Mach number of ? 0.68. Endwall (platform) thermal protection is provided using discrete cylindrical holes with a streamwise inclination angle of 30? and no compound angle relative to the mean approach velocity vector. The surface flow visualization on the inner endwall provided the location of the saddle point and the threedimensional separation lines. Computational predictions showed that the leadingedge horseshoe vortex was confined to approximately 1.5% of the airfoil span for the no film injection case and intensified with low momentum film injection. At the highest blowing ratio, the film cooling jet weakened the horseshoe vortex at the leadingedge plane. The passage vortex was intensified with coolant injection at all blowing ratios. It was seen that increasing average blowing ratio improved the film effectiveness on the endwall. The discharge coefficients calculated for each film cooling hole indicated significant nonuniformity in the coolant discharge at lower blowing ratios and the strong dependence of discharge coefficients on the mainstream static pressure and the location of threedimensional separation lines. Near the airfoil suction side, a region of coalesced film cooling jets providing close to uniform film coverage was observed, indicative of the mainstream acceleration and the influence of threedimensional separation lines.
Show less  Date Issued
 2015
 Identifier
 CFE0005973, ucf:50775
 Format
 Document (PDF)
 PURL
 http://purl.flvc.org/ucf/fd/CFE0005973
 Title
 Microscopic Theory of the Knight Shift.
 Creator

Hall, Bianca, Klemm, Richard, Fernandez, Yan, Rahman, Talat, Del Barco, Enrique, Shivamoggi, Bhimsen, University of Central Florida
 Abstract / Description

This dissertation is the beginning of the development of a microscopic theory of the Knight shift. The Knight shift experiment has been used in superconductivity research throughout history, however, a complete understanding of the Knight shift in conventional as well as unconventional superconductors does not yet exist. Motivated by the results of a literature review, which discusses Knight shift anomalies in multiple superconducting materials, this research studies a new model of the Knight...
Show moreThis dissertation is the beginning of the development of a microscopic theory of the Knight shift. The Knight shift experiment has been used in superconductivity research throughout history, however, a complete understanding of the Knight shift in conventional as well as unconventional superconductors does not yet exist. Motivated by the results of a literature review, which discusses Knight shift anomalies in multiple superconducting materials, this research studies a new model of the Knight shift, which involves the processes involved in nuclear magnetic resonance measurements in metals.The result of this study is a microscopic model of nuclear magnetic resonance in metals. The spins of the spin1/2 local nucleus and its surrounding orbital electrons interact with the arbitrary constant ${\bf B}_0$ and perpendicular timeoscillatory magnetic inductions ${\bf B}_1(t)$ and with each other via an anisotropic hyperfine interaction. An Andersonlike Hamiltonian describes the excitations of the relevant occupied local orbital electrons into the conduction bands, each described by an anisotropic effective mass with corresponding Landau orbits and an anisotropic spin ${\bf g}$ tensor. Local orbital electron correlation effects are included using the meanfield decoupling procedure of Lacroix. The metallic contributions to the Knight shift resonance frequency and linewidth shifts are evaluated to leading orders in the hyperfine and Anderson excitation interactions. While respectively proportional to $(B_1/B_0)^2$ and a constant for weak $B_0(>)(>)B_1$, both shifts are shown to depend strongly upon ${\bf B}_0$ when a Landau level is near the Fermi energy.
Show less  Date Issued
 2015
 Identifier
 CFE0005954, ucf:50808
 Format
 Document (PDF)
 PURL
 http://purl.flvc.org/ucf/fd/CFE0005954
 Title
 Precision Metrology of Laser Plasmas in the XUV Band.
 Creator

Szilagyi, John, Richardson, Martin, Sundaram, Kalpathy, Abdolvand, Reza, Baudelet, Matthieu, Shivamoggi, Bhimsen, University of Central Florida
 Abstract / Description

The XUV band, a region of light spanning the wavelength range of 5  200 nm, is located between the Ultraviolet and Xray regions of the electromagnetic spectrum. It is further divided into a 100  200 nm region called the Vacuum Ultraviolet (VUV), and a 5 () 100 nm region called the Extreme Ultraviolet (EUV). Applications of this light have been slow to develop due to the lack of suitable sources, efficient optics, and sensitive detectors. Recently, many industries such as the semiconductor...
Show moreThe XUV band, a region of light spanning the wavelength range of 5  200 nm, is located between the Ultraviolet and Xray regions of the electromagnetic spectrum. It is further divided into a 100  200 nm region called the Vacuum Ultraviolet (VUV), and a 5 () 100 nm region called the Extreme Ultraviolet (EUV). Applications of this light have been slow to develop due to the lack of suitable sources, efficient optics, and sensitive detectors. Recently, many industries such as the semiconductor manufacturing industry, medical surgery, micromachining, microscopy, and spectroscopy have begun to benefit from the short wavelengths and the high photon energies of this light. At present, the semiconductor chip industry is the primary reason for the investment in, and development of, XUV sources, optics, and detectors. The demand for high power EUV light sources at 13.5 nm wavelength is driven by the development of the next generation of semiconductor lithography tools. The development of these tools enables the continued reduction in size, and the increase in transistor density of semiconductor devices on a single chip. Further development and investigation of laser produced plasma EUV light sources is necessary to increase the average optical power and reliability. This will lead to an increase in the speed of EUV lithographic processes, which are necessary for future generations of advanced chip design, and high volume semiconductor manufacturing. Micromachining, lithography, and microscopy benefit from improvements in resolution due to the shorter wavelengths of light in the VUV band. In order to provide adequate illumination for these applications, sources are required which are brighter and have higher average power. Laser produced plasma (LPP) VUV light sources are used extensively for lithography and defect detection in semiconductor manufacturing. Reductions in the wavelength and increases in the average power will increase the rate and yield of chip manufacture, as well as reduce the costs of semiconductor manufacture.The work presented in this thesis, describes the development of two laser plasma source facilities in the Laser Plasma Laboratory at UCF, which were designed to investigate EUV and VUV laser plasma sources. The HPEUVFacility was developed to optimize and demonstrate a high power 13.5 nm EUV LPP source. This facility provides high resolution spectroscopy across 10.5  20 nm, and absolute energy measurement of 13.5 nm +/ 2% in 2? sr. The VUVMSFacility was developed to investigate VUV emission characteristics of laser plasmas of various target geometries and chemistries. This facility provides absolute calibrated emission spectra for the 124  250 nm wavelength range, in addition to, at wavelength plasma imaging. Calibrated emission spectra, inband power, and conversion efficiency are presented in this work for gas targets of Argon, Krypton, and Xenon and solid targets of Silicon, Copper, Molybdenum, Indium, Tantalum, Tin, and Zinc, across the laser intensity range of 8.0x10^6 () 3.2x10^12 W/cm2.
Show less  Date Issued
 2017
 Identifier
 CFE0006805, ucf:51793
 Format
 Document (PDF)
 PURL
 http://purl.flvc.org/ucf/fd/CFE0006805
 Title
 Chaotification as a Means of Broadband Vibration Energy Harvesting with Piezoelectric Materials.
 Creator

Geiyer, Daniel, Kauffman, Jeffrey L., Das, Tuhin, Moslehy, Faissal, Shivamoggi, Bhimsen, University of Central Florida
 Abstract / Description

Computing advances and component miniaturization in circuits coupled with stagnating battery technology have fueled growth in the development of high efficiency energy harvesters. Vibrationtoelectricity energy harvesting techniques have been investigated extensively for use in sensors embedded in structures or in hardtoreach locations like turbomachinery, surgical implants, and GPS animal trackers. Piezoelectric materials are commonly used in harvesters as they possess the ability to...
Show moreComputing advances and component miniaturization in circuits coupled with stagnating battery technology have fueled growth in the development of high efficiency energy harvesters. Vibrationtoelectricity energy harvesting techniques have been investigated extensively for use in sensors embedded in structures or in hardtoreach locations like turbomachinery, surgical implants, and GPS animal trackers. Piezoelectric materials are commonly used in harvesters as they possess the ability to convert strain energy directly into electrical energy and can work concurrently as actuators for damping applications. The prototypical harvesting system places two piezoelectric patches on both sides of the location of maximum strain on a cantilever beam. While efficient around resonance, performance drops dramatically should the driving frequency drift away from the beam's fundamental frequency. To date, researchers have worked to improve harvesting capability by modifying material properties, using alternative geometries, creating more efficient harvesting circuits, and inducing nonlinearities. These techniques have partially mitigated the resonance excitation dependence for vibrationbased harvesting, but much work remains.In this dissertation, an induced nonlinearity destabilizes a central equilibrium point, resulting in a bistable potential function governing the cantilever beam system. Depending on the environment, multiple stable solutions are possible and can coexist. Typically, researchers neglect chaos and assume that with enough energy in the ambient environment, large displacement trajectories can exist uniquely. When subjected to disturbances a system can fall to coexistent lower energy solutions including aperiodic, chaotic oscillations. Treating chaotic motion as a desirable behavior of the system allows frequency content away from resonance to produce motion about a theoretically infinite number of unstable periodic orbits that can be stabilized through control. The extreme sensitivity to initial conditions exhibited by chaotic systems paired with a pole placement control strategy pioneered by Ott, Grebogi, and Yorke permits small perturbations to an accessible system parameter to alter the system response dramatically. Periodic perturbation of the system trajectories in the vicinity of isolated unstable orbit points can therefore stabilize lowenergy chaotic oscillations onto larger trajectory orbits more suitable for energy harvesting.The periodic perturbationbased control method rids the need of a system model. It only requires discrete displacement, velocity, or voltage time series data of the chaotic system driven by harmonic excitation. While the analysis techniques are not fundamentally limited to harmonic excitation, this condition permits the use of standard discrete mapping techniques to isolate periodic orbits of interest. Local linear model fits characterize the orbit and admit the necessary control perturbation calculations from the time series data.This work discusses the feasibility of such a method for vibration energy harvesting, displays stable solutions under various control algorithms, and implements a hybrid benchtop experiment using MATLAB and LabVIEW FPGA. In conclusion, this work discusses the limitations for widescale use and addresses areas of further work; both with respect to chaotic energy harvesting and parallel advances required within the field as a whole.
Show less  Date Issued
 2017
 Identifier
 CFE0006878, ucf:51718
 Format
 Document (PDF)
 PURL
 http://purl.flvc.org/ucf/fd/CFE0006878