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A Vacuum-Driven Distillation Technology Of Aqueous Solutions And Mixtures, Guo Guangyu

Dissertations

Distillation of aqueous solutions and aqueous mixtures has vast industrial applications, including desalination, wastewater treatment, and fruit juice concentration. Currently, two major distillation technologies are adopted in the industry, membrane separation and thermal distillation. However, both of them face certain inevitable drawbacks. Membrane separation has disadvantages as relying on high-grade energy, requiring membrane, fouling problem, narrow treatment range, limited scalability, and vibrating and noisy operating conditions. Traditional thermal distillation technologies can avoid above concerns but has other shortcomings, such as relatively low energy efficiency and yield rate, complicated and bulky system structure, and scaling problem.

This project proposes an innovative …

A Parametric Computational Fluid Dynamics (Cfd) Study Of In-Line Horizontal Axis Wind Turbines (Hawts) With Yaw, North Alyster Yates

Masters Theses

Because of the constant use of non-renewable fossil fuels, and the enormous impact they have on global warming and pollution, there has been a push to use more eco-friendly and renewable sources for power. One such form is wind power via turbines. The most common form, Horizontal Axis Wind Turbines (HAWTs), can generate massive amounts of power. However, they also have a serious flaw in their design. As the wind passes through the swept area of the blades and past the tower, it creates massive disturbances in the airflow. These disturbances are called a ‘wake’. When trying to create a …

Cedar: A Dimensionally Adaptive Flow Solver For Cylindrical Combustors, Ty R. Hosler

Theses and Dissertations

This thesis discusses the application, evaluation, and extension of dimensionally adaptive meshing to the numerical solution of velocity and pressure fields inside cylindrical reactors. Due to the high length to diameter ratios of many cylindrical reactor vessels the flow field can become axisymmetric, allowing for simplification of the governing equations and significant reduction in computational time required for solution. A fully 3D solver is developed from existing computational tools at BYU and validated against theoretical velocity profiles for pipe flow at various Reynolds numbers, as well as with experimental data for an axial-fired center jet with recirculating flow. Dimensionally adaptive …

Entropy-Based Analysis For Application To Highly Compressible Flows, Ethan A. Vogel

Doctoral Dissertations

Matrix normalizations are a critical component of mathematically rigorous aerodynamics analysis, especially where kinematic and thermodynamic behaviors are of interest. Here, a matrix normalization based around the entropy of a perturbation is derived according to the principles of mathematical entropy analysis and using a general definition of entropy amendable to physical phenomena such as thermal nonequilibrium and caloric and thermal imperfection. This normalization is shown to be closely related to the contemporary Chu energy normalization, expanding the range of validity of that normalization and clarifying the details of its interpretation. This relationship provides a basis for deriving other normalizations. Entropy …

Design Of A 300cm2 Pemfc Stack With Force And Cfd Simulation To Optimize Flow Channels, Gasket Design, And Clamping Forces., Robert M. Ench

Electronic Theses and Dissertations

Proton exchange membrane fuel cells are important to the future of green energy as hydrogen can be made with green technologies and store energy for later use. Fuel cells can efficiently convert the hydrogen to electricity as needed. This study uses Solidworks simulation to make design improvements to the fuel cell before the prototype build stage of testing; this saves money and time by reducing the prototype builds needed.

In this study, a multi-channel serpentine design with two outlets versus a single outlet is evaluated using CFD to investigate pressure drop. Lower pressure drops are desirable as less energy input …

Quantification Of Velocity At The Sparkplug In A Lab Scale Combustion Chamber, Mayur Panduranga Kodikal

Electronic Theses and Dissertations

Lean burn has been considered an effective strategy to improve the thermal efficiency of spark-ignition engines. Under lean or diluted conditions, however, the combustion speed is reduced. Therefore, to speed up the combustion, in-cylinder turbulence is induced which may impede the spark initiation. This research aims to quantify the turbulence in a constant volume optical combustion chamber.

An Improved Delayed Detached Eddy Simulation (IDDES) study was done to understand the turbulence characteristics of the flow in the optical chamber. Spark anemometry was used to obtain a relationship between the spark plasma evolution and freestream velocity. Finally, this technique has been …

Cfd Analysis Of Subcutaneous Deposition And Dispersion Of Insulin In Adipose Tissue, Ryan C. Lubbers

Masters Theses

Drug delivery is the most important factor of many therapies, but a lack of technology and research have led to a very generalized understanding of drug kinetics. Insulin pump therapy for the treatment of Type 1 Diabetes depends on precise delivery of the hormone into the adipose region between the dermis and underlying muscle. The kinetics of insulin within the adipose tissue environment is not well understood and varies greatly case to case. The use of computation fluid dynamics (CFD) models to study insulin kinetics in relation to influential factors will lead to a better understanding of the characteristics of …

Flow Characterization In Mine Ventilation Fan Blade Design Using Cfd, Anwar Endris Hassen

Journal of Sustainable Mining

In axial ventilation fans, the generation of a uniform flow velocity is desirable for better efficiency. To that end, different fan blade types have been developed to achieve better flow uniformity. This article aimed to characterize the flow distribution and its uniformity in four blade designs, namely constant chord, tapered blade, skewed blade, and tapered skewed blade, using Computational Fluid Dynamics (CFD). The study employs an iterative study where key study decisions are made as the study progresses. The study began with the selection of a blade profile for the study. A comparative study between the NACA seven-digit and four-digit …

Cfd Investigation Of The Drag Effects On An Aircraft By Means Of Altering The Wing Or Canard Size And Position, Taylor Brown

Theses and Dissertations

The stability and maneuverability of aircraft are some key factors for selecting the locations of wings or canards on the fuselage. Another important variable that is considered in the design of an aircraft is drag force which impacts fuel efficiency. This research investigates how drag force of a surrogate aircraft is affected by the placement of the wing or canard along the fuselage. Unique for this study is the placement of the canard in the fuselage nose region, with the leading edge upstream of the nose, resembling the shape of a hammerhead shark's head. When the leading edge of all …

Refinement And Automation Using Algorithmic Control Of Breathforce, A Respiratory Training System For Patients With Spinal Cord Injuries., Anna Goestenkors

Electronic Theses and Dissertations

Spinal cord injuries (SCI) can lead to impaired respiratory and cardiovascular function and a general decrease in lung compliance. This can complicate breathing as well as impair the ability to sigh, cough, and clear secretions, leading to increased risk of respiratory infections. Respiratory training has been shown to combat these effects. BreathForce is under active development to create a user-centric inspiratory-expiratory device that is an affordable option for at-home training. This study reports on the refinement of valve design and automation incorporated into BreathForce to enhance and enforce clinical practices and processes as part of the respiratory training protocol used …

Venturi Meter Performance When Installed On The Branch Of A Tee Junction With Converging Run Flow, E. Elliot Naulu

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Venturi flow meters are often installed downstream of disturbances such as a tee junction, valve, or elbow. In such a case, a laboratory calibration may be needed to measure the Venturi meter’s performance under said limitations so that accurate metering is achieved. However, in some cases, laboratory calibration may not be possible.The purpose of this research was to investigate Computational Fluid Dynamics (CFD) ability to simulate a Venturi meter installed on the branch of a tee junction with converging run flow.

This study used CFD to compare against laboratory results to illustrate CFD’s capability as a calibration method. The results …

Numerical Investigation Of The Thermo-Hydraulic Performance Of Water-Based Nanofluids In A Dimpled Channel Flow Using Al₂O₃, Cuo, And Hybrid Al₂O₃-Cuo As Nanoparticles, Farid Ahmed, Md Atrehar Abir, Muhtasim Fuad, Farhana Akter, Palash K. Bhowmik, Syed B. Alam, Dinesh Kumar

Nuclear Engineering and Radiation Science Faculty Research & Creative Works

In this study, the authors study the impact of spherical dimple surfaces and nanofluid coolants on heat transfer and pressure drop. The main objective of this paper is to evaluate the thermal performance of nanofluids with respect to different Reynolds numbers (Re) and nanoparticle compositions in dimpled channel flow. Water-based nanofluids with Al₂O₃, CuO, and Al₂O₃-CuO nanoparticles are considered for this investigation with 1%, 2%, and 4% volume fraction for each nanofluid. The simulations are conducted at low Reynolds numbers varying from 500 to 1250, assuming constant and uniform heat flux. The …

Numerical Study On Oscillating Flow Over A Flat Plate Using Pseudo-Compressibility In Intermittent Turbulent Regime, Shivank Srivastava Mr.

University of New Orleans Theses and Dissertations

A Computational Fluid Dynamic (CFD) in-house code is developed to study unsteady characteristics of incompressible oscillating boundary layer flow over a flat plate under laminar and intermittently turbulent condition using pseudo-compressible unsteady Reynolds Averaged Navier- Stokes (RANS) model. In the in-house code, the two-dimensional, unsteady conservation of mass and momentum equations are discretized using finite difference techniques which employs second order accurate (based on Taylor series) central differencing for spatial derivatives and second order Runge-Kutta accurate differencing for temporal derivatives. The in-house code employs Fully Explicit-Finite Difference technique (FEFD) to solve the governing differential equations of the mathematical model. In …

Numerical Study And Validation Of Melting And Solidification In Pcm Embedded Heat Exchangers With Straight Tube, Tanjebul Alam, Daniel Bacellar, Jiazhen Ling, Vikrant Aute

International Refrigeration and Air Conditioning Conference

Latent heat thermal energy storage (LHTES) systems have shown great potential to enable reliable use of renewable energy and load shifting. LHTES offer high storage density and release energy at near constant temperature because of its use of phase change materials (PCMs). The cylindrical PCM heat exchangers (PCMHX) are one of the most used technologies due to their simplicity. Numerical models for such PCMHX enable engineers to estimate their performance for different design parameters and operating conditions without having to test them all. However, modeling the phase change phenomena can be challenging. To better understand the difficulties involving accurate modeling …

A Comparison Of Interpolation Methods In Fast Fluid Dynamics, Eric Leonard, Hongtao Qiao, Saleh Nabi

International High Performance Buildings Conference

This paper examines the use of OpenFOAM’s cellPoint and cellPointWallModified interpolation routines in fast fluid dynamics (FFD). In addition, an arrangement of OpenFOAM’s data structures is proposed which speeds up FFD and an adjustment to FFD which incorporates the Boussinesq approximation is discussed. The findings of this paper show that the use of the cellPointWallModified interpolation routine in FFD produces results closer to reference data in higher Reynolds number flows than the use of the cellPoint interpolation routine, a result which highlights the important role that interpolation plays in the accuracy of FFD.

3d Cfd Simulation Of A New Ventilated Roof, Michele Calati, Luca Doretti, Cristiano Gatto, Simone Mancin

International High Performance Buildings Conference

In the last decades, energy management and saving have become challenging issues. Considering the building sector (residential or industrial), different technologies have been developed in order to realize tangible energy savings, such as: ventilated roof, double facades, glazed surfaces, etc. Nonetheless, it is important for these new technologies to contemporary assure the human thermal comfort. Passive cooling (or heating) technologies are of actual interest. Low or near-zero energy buildings can only be realized as a result of the good design of all their components; specifically, the roofs call for particular attention as they take large parts of a building’s total …

Cfd Analysis Of An Orc Vane Expander Using Openfoam Solver, Sham Ramchandra Rane, Giuseppe Bianchi, Ahmed Kovačević, Roberto Cipollone

International Compressor Engineering Conference

Recent studies on the use of 3D Computational Fluid Dynamics (CFD) for the analysis and design of sliding vane machines has proved beneficial for the detailed evaluation and optimisation of the vane expanders for a given working fluid and operating condition. The authors have earlier developed a customised rotor grid generator for integration with commercial CFD solvers and validated it for use in typical small-scale ORC expanders for waste heat recovery. In this paper, this customised grid generation is extended to an open source CFD solver OpenFOAM, by using a connectivity methodology originally developed for roots blower and twin-screw machines. …

Parametric Studies On A New Schukey Type Rotary Compressor, Bin Cui, Martin Gottschlich, Ulrich Lüdersen, Stephan Kabelac

International Compressor Engineering Conference

Efficient compressors are generally important for applications in air conditioning and refrigeration systems. Therefore, innovative technologies are needed to improve their performance and expand their area of application. A new type of rotary compressor, called “Schukey compressor”, has been investigated both experimentally and theoretically. The Schukey-technology goes back to its founder Jürgen Schukey in 1987, who invented a special gear that enables two rotors to rotate out of phase in the same direction within the compressor housing. Each rotor consists of four rectangular shaped piston wings that interlock and perform non-uniform rotary movements, leading to a periodic change of the …

A Study On Computational Cost Reduction Of Simulations Of Phase-Change Material (Pcm) Embedded Heat Exchangers, Daniel Bacellar, Tanjebul Alam, Jiazhen Ling, Vikrant Aute

International Refrigeration and Air Conditioning Conference

Thermal storage can be implemented using Phase-Change Materials (PCM), which absorb significant latent heat with a relatively small temperature change. PCM phase-change processes are transient and are driven by thermal diffusion and natural convection – the latter, especially for melting process. Modeling and simulation of PCM heat exchangers (HX’s) is typically computationally intensive due to the relatively complex time-dependent physics. Most of the PCM modeling work in the literature uses high-order modeling tools such as Computational Fluid Dynamics (CFD) and Lattice-Boltzmann Method (LBM). For design purposes, the existing PCM modeling approaches are not practical, limiting researchers in their ability to …

The Effect Of Fuel Injector Spacing, Angle, And Blowing Ratio On The Fuel Air Mixing Performance Of A Scramjet Engine, Jonathan R. Copeland

Honors College Theses

In the operation of a Scramjet engine, which operates at hypersonic velocities, one of the most important factors is mixing the fuel and air before the high velocity air stream through the engine blows the mixture out of the engine before it could burn. Because of the importance of rapidly mixing fuel and air within a Scramjet engine, there are multiple design elements used to increase mixing. One of which is called a flame holder cavity, which is usually located behind fuel injectors, and designed with an open (length to depth ratio is less than 10) geometry to promote recirculation …

Mathematical Model Of Ice Slurry Flow To Predict Agglomerations And Phase Interaction Effects, Shaimaa Hefny Badawi, Christiane Thomas, Ullrich Hesse

International Refrigeration and Air Conditioning Conference

Ice slurry is an energy-intensive secondary fluid, which may play an important role in various cooling purposes. From the system design perspective, it is of great importance to obtain detailed information of the ice slurry flow. A quantification of the complex two-phase flow characteristic is difficult due to the heterogeneous ice slurry flow. The paper includes the theoretical analysis of the ice slurry behaviour with different ice particle conditions (concentration, size) considering pressure drop and agglomeration. In addition to the mathematical model analyses of all important balance equations and other sub-equations (granular properties, phase interactions), various parameters influencing the behaviour …

A Cfd Investigation Of The Suction Process In A Screw Compressor, Matt Cambio, Scott Branch, Alberto Scala, Jonathan Harrison

International Compressor Engineering Conference

Computational fluid dynamics (CFD) has been widely applied to screw compressors. CFD has allowed engineers to gain a better understanding of the complex flows that occur inside the screw compressor. In many cases, the details revealed are only possible with CFD compared to 1-D simulations. Both CFD and 1D can reduce development costs and as in this case, guide decisions on the choice of hardware to be tested. This paper presents the flow details of the suction process in a screw compressor and the effects on performance. The cases presented are a twin screw rotor set applied to two different …

Cfd Analysis Of A Twin Screw Compressor With Oil Injection, Junfeng Wang, Hui Ding, Sham Rane, Ahmed Kovacevic

International Compressor Engineering Conference

In this paper, a full 3D transient Computational Fluid Dynamics (CFD) model of a twin screw compressor with oil injection is described in detail. Volume of Fluid (VOF) two phase flow model is used for gas and liquid phases. The rotor meshes are generated by SCORGTM grid generator and read into the CFD solver at each time step. The simulation runs efficiently and results are obtained in about 12 hours on 24 CPU cores. The CFD prediction of air mass flow rate and indicated power has a good agreement with the experimental data measured at City University of London. The …

Application Of Computational Fluid Dynamics To The Lubrication Study Of An Oil-Injected Screw Compressor, Sheng-Hung Hsieh, Jin-Wei Zhang, Chi-Shun Huang

International Compressor Engineering Conference

Computational fluid dynamics and mesh generation tools have been well developed, and could be used to calculate the performance of an oil-injected screw compressor. Designers could now effectively obtain reliable results of efficiency, temperature, force and torque. Some physical phenomena inside a screw compressor are not easy to be observed through experiments, such as the oil distribution and the oil film thickness on the rotor surface. Under the ideal lubrication condition, the oil film of proper thickness should be maintained on the local surfaces which are going to contact with each other. This could be numerically explored by computational fluid …

Numerical Analysis On A Perforated Muffler Applied In The Discharge Chamber Of A Twin Screw Refrigeration Compressor Based On Fluid-Acoustic Coupling Method, Shizhong Sun, Ziwen Xing, Wenqing Chen, Minglong Zhou, Yu Hua Huang, Po Chia Su

International Compressor Engineering Conference

The twin screw compressor has been widely used in the refrigeration systems due to advantages such as compact structure, stable operation, high efficiency and good adaptability. Intermittent gas flow generates gas pulsation that cause serious problems such as structural vibration and noise in the twin screw refrigeration compressor. Because the mechanical noise can be controlled well with the improvement of machining and assembly accuracy, the aerodynamic noise induced by gas pulsation even has become the main noise source of the twin screw refrigeration compressor. In order to reduce the pressure pulsation, a broadband perforated panel muffler applied in the discharge …

Computational Fluid Dynamics And Fluid Structure Interaction Research On Flow In A Glenn Shunt And A Flexible Tube And On A Cantilevered Plate, Chunhui Wang

McKelvey School of Engineering Theses & Dissertations

This thesis employs Computational Fluid Dynamics (CFD) simulation technology to solve three flow problems: (1) Blood flow in a Bidirectional Glenn Shunt and a combined Bidirectional Glenn Shunt (BGS) and Blalock-Taussing (BT) Shunt. This shunt is used to address the problem of Cyanosis or “Blue Baby Syndrome,” which is an infant disorder that affects the newly born babies whose skins turn blue or purple because of lack of necessary blood flow between heart and lung due to pulmonary vascular blockage. The goal of this study was to evaluate the performance of BGS and combined BGS+BT shunt in achieving the desired …

Computational Fluid Dynamics (Cfd) Modeling Of Two Phase Refrigerant Flow In Evaporator Refrigerant Distribution System, Saugata Sarkar

International Refrigeration and Air Conditioning Conference

The biggest challenge in the evaporator distribution system is to maintain a uniform distribution of vapor and liquid phases in the evaporator. Uneven distribution will create poor refrigeration effect. In order to study flow distribution in the evaporator distributors, a two-phase CFD model has been developed for three different idealized distributors with various orientations of flow paths and geometrical parameters. The CFD model predicted flow maps, vapor qualities and, mass flow rates in the distributors as a function of various geometrical and inlet flow parameters. Refrigerant R134a is used as a working fluid with inlet saturation temperature 7°C with various …

Numerical Simulation Of Losses In Four-Way Pipe Junctions, Simon Barth

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

To design pipelines, engineers need to know how much energy the fluid in the pipe has at different locations in the pipe network. The energy the fluid has comes in the form of pressure, velocity, and elevation. As fluid travels through a pipe, it loses energy for many different reasons. Some of those reasons include friction between the fluid and the pipe wall, shear forces within the fluid, changes in flow direction, changes in elevation, or various pipe fittings like elbows, tee’s, valves, reducers, and expanders. Many of the causes of energy loss are well researched. One cause of energy …

Thermal Design Analysis Of Server Chassis Manifolds For Liquid Cooled Servers Using Cfd, Kaustubh Kantilal Adsul

Mechanical and Aerospace Engineering Theses

Direct-to-chip liquid cooling is one of the most popular methods in data center thermal management when it comes to cooling high chip power densities. A cold plate-based liquid cooling system contains various components such as pumps, data center room, and rack-level manifolds, and server chassis-level manifold. Efficient coolant distribution to the heat-dissipating cold plates plays an important role in both the thermal and hydraulic performance of the server. It is, thus, very important to design and manufacture server chassis manifold geometry that can perform efficiently under the anticipated heat loads and coolant flow rates. In the present thesis, two such …

Cfd Analysis Of Acoustofluidic Channels And The Effects On Biologic Delivery., Zachary T. Long

Electronic Theses and Dissertations

T-cell transformation is an ever-expanding treatment for several types of cancer, with a potential to be adapted to other disorders in which the immune system plays a key role in the pathophysiology. Currently, all FDA approved chimeric antigen receptor (CAR) T-cell cancer therapies rely on transformation via viral transduction. However, viral transduction is plagued by poor consistency and the potential to create adverse immune reactions when T-cells are reintroduced into a patient. Other transformation methods are being explored, with an alternative called acoustofluidic sonoporation showing promise. In these procedures, cells are passed through a channel, of the millimeter scale, while …