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Methods For Decarbonized Aeroengine Combustor Design, Robert T. Prater

Masters Theses

There exists an urgent need to decarbonize the civil transportation sector in order to address global warming concerns and its effects. Alternate and sustainable fuel types for combustion systems must be pursued to mitigate the dependency on fossil fuels for power generation. Possible alternative options for aeroengine combustion and propulsion include batteries or hydrogen fuel for fuel-cells or thermal-powered gas turbines. More specifically, thermal-powered aeroengines with premixed flame regimes can promise ultra-low emissions. Future aeroengine combustors operating in highly swirled premixed mode with hydrogen/air mixtures are central to this paper. Prior to the implementation and design of such systems, premixed …

A Cfd Study Of Operation Room Air Conditioning: Air Curtain Performance, Spencer Lee Boer

Masters Theses

An operation room is a critical environment when it comes to the safety of patients undergoing surgery. There are a lot of factors that go into reducing Surgical Site Infections (SSI) following a surgery. This comes in the form of cleaning standards, surgical practices, but also environment controls. The characteristics of airflow within an operation room are related to the risk of an SSI. Some of these factors are temperature, velocity, and turbulent air around an open wound which could increase the chance of bacteria or other particles entering the very vulnerable patient. As clean room standards continue to be …

Computational Fluid Dynamics Models Of Electromagnetic Levitation Experiments In Reduced Gravity, Gwendolyn Bracker

Masters Theses

Electromagnetic levitation experiments provide a powerful tool that allows for the study of nucleation, solidification and growth in a containerless processing environment. Containerless processing allows for the study of reactive melts at elevated temperatures without chemical interactions or contamination from a container. Further, by removing the interface between the liquid and its container, this processing technique allows for greater access to the undercooled region for solidification studies. However, in these experiments it is important to understand the magnetohydrodynamic flow within the sample and the effects that this fluid flow has on the experiment.

A recent solidification study found that aluminum-nickel …

Numerical Modeling Of Capillary-Driven Flow In Open Microchannels: An Implication Of Optimized Wicking Fabric Design, Mehrad Gholizadeh Ansari

Masters Theses

"The use of microfluidics to transfer fluids without applying any exterior energy source is a promising technology in different fields of science and engineering due to their compactness, simplicity and cost-effective design. In geotechnical engineering, to increase the soil's strength, hydrophilic wicking fibers as type of microfluidics have been employed to transport and drain water out of soil spontaneously by taking advantage of natural capillary force without using any pumps or other auxiliary devices. The objective of this study is to understand the scientific mechanisms of the capability for wicking fiber to drain both gravity and capillary water out of …

A Computational Evaluation Of Transonic Wind Tunnel Wall Interference On High Aspect Ratio Models In The Arnold Engineering Development Complex 16 Foot Transonic Tunnel, William Calain Schuman

Masters Theses

One of the inherent difficulties in utilizing a ventilated test section wind tunnel is the interaction of the model flow field and the test section walls. If high quality aerodynamic data is required for the system under test it is necessary to determine the impact of the test section walls on the flow field around the model. A parametric study was undertaken using the CFD code USM3Dns to determine the impact of model size and wingspan on observed transonic wind tunnel wall interference. The study used a simplified model of the Propulsion Wind Tunnel 16T test section as the test …

Development And Verification Of A Navier-Stokes Solver With Vorticity Confinement Using Openfoam, Austin Barrett Kimbrell

Masters Theses

Vorticity Confinement (VC) is a numerical technique which enhances computation of fluid flows by acting as negative diffusion within the limit of vortical regions, preventing the inherent numerical dissipation present with conventional methods. VC shares similarities with large eddy simulation (LES), but its behavior is based on a stable negative dissipation of vortical structures controlled by the automatic balance between two parameters, μ [mu] and ε [epsilon].

In this thesis, three-dimensional, parallel-computing Navier-Stokes solvers with VC are developed using the OpenFOAM computational framework. OpenFOAM is an open-source collection of C++ libraries developed for computational fluid dynamics. Object-oriented programming concepts are …