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Full-Text Articles in Engineering
A Full Coverage Film Cooling Study: The Effect Of An Alternating Compound Angle, Justin Hodges
A Full Coverage Film Cooling Study: The Effect Of An Alternating Compound Angle, Justin Hodges
Electronic Theses and Dissertations
This thesis is an experimental and numerical full-coverage film cooling study. The objective of this work is the quantification of local heat transfer augmentation and adiabatic film cooling effectiveness for two full-coverage film cooling geometries. Experimental data was acquired with a scientific grade CCD camera, where images are taken over the heat transfer surface, which is painted with a temperature sensitive paint. The CFD component of this study served to evaluate how well the v2-f turbulence model predicted film cooling effectiveness throughout the array, as compared with experimental data. The two staggered arrays tested are different from one another through …
Development Of Full Surface Transient Thermochromic Liquid Crystal Technique For Internal Cooling Channels, Lucky Tran
Development Of Full Surface Transient Thermochromic Liquid Crystal Technique For Internal Cooling Channels, Lucky Tran
Electronic Theses and Dissertations
Proper design of high performance industrial heat transfer equipment relies on accurate knowledge and prediction of the thermal boundary conditions. In order to enhance the overall gas turbine efficiency, advancements in cooling technology for gas turbines and related applications are continuously investigated to increase the turbine inlet temperature without compromising the durability of the materials used. For detailed design, local distributions are needed in addition to bulk quantities. Detailed local distributions require advanced experimental techniques whereas they are readily available using numerical tools. Numerical predictions using a computational fluid dynamics approach with popular turbulence models are benchmarked against a semi-empirical …
Multiobjective Design Optimization Of Gas Turbine Blade With Emphasis On Internal Cooling, Narasimha Nagaiah
Multiobjective Design Optimization Of Gas Turbine Blade With Emphasis On Internal Cooling, Narasimha Nagaiah
Electronic Theses and Dissertations
In the design of mechanical components, numerical simulations and experimental methods are commonly used for design creation (or modification) and design optimization. However, a major challenge of using simulation and experimental methods is that they are timeconsuming and often cost-prohibitive for the designer. In addition, the simultaneous interactions between aerodynamic, thermodynamic and mechanical integrity objectives for a particular component or set of components are difficult to accurately characterize, even with the existing simulation tools and experimental methods. The current research and practice of using numerical simulations and experimental methods do little to address the simultaneous “satisficing” of multiple and often …
Designing Of Energy Efficient Indoor Environments Using A Localized Radial Basis Function Meshless Method, Victor Huayamave
Designing Of Energy Efficient Indoor Environments Using A Localized Radial Basis Function Meshless Method, Victor Huayamave
Electronic Theses and Dissertations
Around the world, the energy over consumption issue has been one of the key socio-economic and political challenges, which has drastically worsened over the last few years. Over the years engineers and environmentalists have proposed several approaches to improve energy efficiency. One is to reduce energy demand by improving consumption habits and a second approach is to introduce the use of a "greener" concept by using biomaterials in a diverse and more efficient manner in engineering construction to create energy efficient environments. This work will investigate the effects of using "green" stabilized earth materials to provide and enhance thermal regulation …
High Heat Flux Spray Cooling With Ammonia On Enhanced Surfaces, Huseyin Bostanci
High Heat Flux Spray Cooling With Ammonia On Enhanced Surfaces, Huseyin Bostanci
Electronic Theses and Dissertations
Many critical applications today, in electronics, optics and aerospace fields, among others, demand advanced thermal management solutions for the acquisition of high heat loads they generate in order to operate reliably and efficiently. Current competing technologies for this challenging task include several single and two phase cooling options. When these cooling schemes are compared based on the high heat flux removal (100-1000 W/cm2) and isothermal operation (within several oC across the cooled device) aspects, as well as system mass, volume and power consumption, spray cooling appears to be the best choice. The current study focused on high heat flux spray …
A Model Integrated Meshless Solver (Mims) For Fluid Flow And Heat Transfer, Salvadore Gerace
A Model Integrated Meshless Solver (Mims) For Fluid Flow And Heat Transfer, Salvadore Gerace
Electronic Theses and Dissertations
Numerical methods for solving partial differential equations are commonplace in the engineering community and their popularity can be attributed to the rapid performance improvement of modern workstations and desktop computers. The ubiquity of computer technology has allowed all areas of engineering to have access to detailed thermal, stress, and fluid flow analysis packages capable of performing complex studies of current and future designs. The rapid pace of computer development, however, has begun to outstrip efforts to reduce analysis overhead. As such, most commercially available software packages are now limited by the human effort required to prepare, develop, and initialize the …
Pressure Drop And Endwall Heat Transfer Effects Of Porous Turbulators In A Rectangular Channel, Jared Pent
Pressure Drop And Endwall Heat Transfer Effects Of Porous Turbulators In A Rectangular Channel, Jared Pent
Electronic Theses and Dissertations
This study examines the local and averaged endwall heat transfer effects of a staggered array of porous pin fins within a rectangular channel. The porous pin fins were made from aluminum and had a pore density of 10 pores per inch (PPI). The pressure drop through the channel was also determined for several flow rates and presented in terms of the friction factor. Local heat transfer coefficients on the endwall were measured using Thermochromic Liquid Crystal (TLC) sheets recorded with a charge-coupled device (CCD) camera. Static and total pressure measurements were taken at the entrance and exit of the test …
Wall Heat Transfer Effects In The Endwall Region Behind A Reflected Shock Wave At Long Test Times, Corey Frazier
Wall Heat Transfer Effects In The Endwall Region Behind A Reflected Shock Wave At Long Test Times, Corey Frazier
Electronic Theses and Dissertations
Shock-tube experiments are typically performed at high temperatures (≥1200K) due to test-time constraints. These test times are usually ~1 ms in duration and the source of this short, test-time constraint is loss of temperature due to heat transfer. At short test times, there is very little appreciable heat transfer between the hot gas and the cold walls of the shock tube and a high test temperature can be maintained. However, some experiments are using lower temperatures (approx. 800K) to achieve ignition and require much longer test times (up to 15 ms) to fully study the chemical kinetics and combustion chemistry …
Comparison Of Square-Hole And Round-Hole Film Cooling: A Computational Study, Michael Glenn Durham
Comparison Of Square-Hole And Round-Hole Film Cooling: A Computational Study, Michael Glenn Durham
Electronic Theses and Dissertations
Film cooling is a method used to protect surfaces exposed to high-temperature flows such as those that exist in gas turbines. It involves the injection of secondary fluid (at a lower temperature than that of the main flow) that covers the surface to be protected. This injection is through holes that can have various shapes; simple shapes such as those with a straight circular (by drilling) or straight square (by EDM) cross-section are relatively easy and inexpensive to create. Immediately downstream of the exit of a film cooling hole, a so-called horseshoe vortex structure consisting of a pair of counter-rotating …
Effect Of Coriolis And Centrifugal Forces On Turbulence And Transport At High Rotation And Buoyancy Numbers, Ahmad Khalaf Sleiti
Effect Of Coriolis And Centrifugal Forces On Turbulence And Transport At High Rotation And Buoyancy Numbers, Ahmad Khalaf Sleiti
Electronic Theses and Dissertations
This study attempts to understand one of the most fundamental and challenging problems in fluid flow and heat transfer for rotating machines. The study focuses on gas turbines and electric generators for high temperature and high energy density applications, respectively, both which employ rotating cooling channels so that materials do not fail under high temperature and high stress environment. Prediction of fluid flow and heat transfer inside internal cooling channels that rotate at high rotation number and high density ratio similar to those that are existing in turbine blades and generator rotors is the main focus of this study. Both …