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Ammonium bisulfate (ABS) is an acidic deposit that can form on the metal elements of air preheaters in power boilers, leading to unit operational issues. As a byproduct of the Selective Catalytic Reduction (SCR) systems for nitrogen oxide (NOx) emissions control, ABS could result in unit efficiency deterioration, even unit outage. ABS formation temperature is an important factor in controlling the issues associated with ABS fouling problems. If the ABS formation temperature could be monitored, the ABS deposition location could be identified.

Computational fluid dynamics (CFD) simulations have been conducted for different configurations of pre-designed multiple hydrokinetic turbines. The turbines are modeled physically within the fluid domain instead of low fidelity actuator lines or actuator disk modeling approaches. The turbulence model, k-ω Shear Stress Transport (SST) was employed to resolve turbulent flow field. The primary focus of this study is to investigate transient behavior of multiple turbines and providing solutions to enhance downstream turbine performance in close proximity to the upstream turbine wake.

Finite Element Analysis (FEA) can be a great tool for analyzing the structural integrity of any mechanical design. Paired with Computational Fluid Dynamics (CFD) the forces can be evaluated on a hydro turbine allowing for such an analysis. In this case, two micro hydro turbines were analyzed, an Archimedes Screw design, in the case of an available head, and a hydrokinetic design, aiming at extracting the kinetic energy of a river.

Flows past bluff bodies are encountered in many engineering applications. The bluff body situated in the flow experience a significant amount of pressure drag force. Therefore, it is important to predict flow conditions around bluff bodies when designing bridges, platforms, pipelines near seabed, offshore structures, and hydropower systems. In several engineering applications, structures could often be placed near surfaces. Transient flows past rectangular plates in the vicinity of surfaces are investigated in this study.

Computational fluid dynamics simulations were conducted to study the unit performance of direct contact membrane distillation for seawater desalination process in three-dimensional modules. A parametric study was conducted to assess the effects of the mem

Forward Osmosis is a natural phenomenon that takes places across a semi-permeable membrane when there is a concentration difference across the membrane. Pure water permeates to the highly concentrated channel until the concentration across the membrane equilibrates. In water desalination applications, the same principle is applied. Spiral-wound membrane, flat sheet, or hollow fiber module are typical configurations in forward osmosis desalination modules.

Rare earth elements (REEs) are valuable raw materials for various applications in modern high technology industries. For most countries, the majority of REEs are imported from abroad. Therefore, developing an alternative method to produce REEs is significant to the national security of those countries. The extraction of selected REEs from acid mine drainage (AMD) by supercritical CO2 (sCO2) was investigated in this study. The solubility of different ligands in sCO2 has significant impact on the extraction efficiency of REEs.

The von Willebrand Factor (vWF) is a large multimeric protein in the blood that aids in blood clotting. It activates the clotting cascade at specific time and specific place, which is one of the human body's masterpieces in targeted molecular manipulation. Hydrodynamic forces trigger conformational changes of vWF, by which its potency and reactivity are regulated. In this thesis, inspiration is taken from novel findings in vWF experiments. The present study aims to describe the behaviors in this process within the context of polymer science.

This work investigates the single-relaxation-time Lattice Boltzmann Method and how to develop it into a full hydrodynamic and thermal modeling scheme. First the single-relaxation time isothermal Lattice Boltzmann Method is outlined, beginning with the fundamentals of the lattice model and then proceeding through the necessary governingequations for the two-dimensional, nine-directional lattice. The governing equations are then presented in a discretized form to be used for simulation, followed by treatment ofboundary conditions.

To explore non-energy study uses of coal, an approach of anthracite coal activation and its Hg capture capacity was investigated to establish the feasibility of using anthracite for Hg emissions adsorption in the flue gas of coal-fired power plants. This research project was performed in two stages: an anthracite sample activation stage and a Hg adsorption stage. In the first step, anthracite coal produced by Blaschak Coal Corporation was activated by mixing it with potassium hydroxide (KOH) powder and heated to high temperature.

Numerical analyses are performed for reverse osmosis gas separation modules consisting of hollow fiber membranes. Computational fluid dynamic simulations are conducted to study steady state flow and mass transport in three-dimensional separation modules. The fluid is a binary mixture of carbon dioxide (CO2) and methane (CH4). The mixture flows in a direction parallel to the membrane axis. The separation module consists of an inline and a staggered arrangement of hollow fibers with two different spacing.

Computational fluid dynamics simulations were conducted to study the performance of the vacuum membrane distillation on hollow fiber membrane module to serve the seawater desalination sector. The membrane thickness of the hollow fiber membrane is seen in a wide range in the published studies which brings the research attention to address its effect. Therefore, a study was conducted to test the different membrane thickness of the hollow fiber membrane on the module performance. Two different configurations of a single hollow fiber membrane module were investigated.

The Lattice Boltzmann method is an effective computational fluid dynamics tool to study complex flows. Unlike conventional numerical schemes based on discretization of macroscopic continuum equations, the Lattice Boltzmann method is based on particles and mesoscopic kinetic equations. Single-Relaxation Time Lattice Boltzmann Method (SRTLBM) with Smagorinsky LES model is applied to simulate high Reynolds number jet flows of single and multiphase flows emanating. The multi-block approach is implemented to refine the mesh when the high resolution is needed in the region around the core jet.

Water desalination by membranes constitutes the majority of the low-quality water purication systems that extends across many different techniques. This study considers transport phenomena in reverse osmosis (RO) and vacuum membrane distillation (VMD) modules using computational techniques. Reverse osmosis is a pressure-driven separation method using semi-permeable membranes featuring nanoporous structures.

A mercury detection system was built and tested to help assess the mercury absorption ability of synthetic disks, made of Kapton polyimide film, under simulated flue gas conditions at different temperature levels. These synthetic disks would be part of a continuous mercury monitoring system developed by UHV, Inc. and the Lehigh University Energy Research Center. Evaluation of the disks was based on mercury absorption efficiency, calculated from the difference in mercury concentration before and after placing the discs into the detection system.

This thesis looks at class traditions of students at Lehigh University from the founding of the institution in 1865 until the early 1970s, specifically examining how and why they waxed and waned through the years. Traditions for and by students were readily embraced by the undergraduates. Examples included the Calculus Cremation, the cane rush, freshman/sophomore hazing rituals, and campus rules, such as the one dictating the wearing of a freshman hat known as a dink.

A finite volume numerical method is introduced to perform the direct numerical simulation for two-phase immiscible and incompressible fluids. The Navier-Stokes equation is discretized by the staggered mesh spatially and advected temporally with the 4th order Runge-Kutta scheme. CFL conditions involving the effect from the convective term, viscous term, stiff source term and heat transfer are applied to meet the stringent limitation on the time step. Energy equation is coupled with the Navier-Stokes equation when the study of heat transfer is included.