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Heat Transfer In A Coupled Impingement-Effusion Cooling System, Mark W. Miller 2011 University of Central Florida

Heat Transfer In A Coupled Impingement-Effusion Cooling System, Mark W. Miller

Electronic Theses and Dissertations

Gas turbine engines are prevalent in the today’s aviation and power generation industries. The majority of commercial aircraft use a turbofan gas turbine engines. Gas turbines used for power generation can achieve thermodynamic efficiencies as high as 60% when coupled with a steam turbine as part of a combined cycle. The success of gas turbines is a direct result of a half century’s development of the technology necessary to create such efficient, powerful, and reliable machines. One key area of technical advancement is the turbine cooling system. In short, increasing the turbine inlet temperature leads to a rise in cycle …


Purge And Secondary Flow Interaction Control By Means Of Platform Circumferential Contouring, Melissa Harris 2011 University of Central Florida

Purge And Secondary Flow Interaction Control By Means Of Platform Circumferential Contouring, Melissa Harris

Electronic Theses and Dissertations

This study presents an attempt to reduce the losses produced by the purge flow in a turbine stage by incorporating circumferential platform contouring. Two contours are proposed and compared against a baseline at different levels of swirl. The computational simulations were performed using a RANS three-dimensional Computational Fluid Dynamics code with the Shear Stress Transport turbulence model. The results of steady simulations demonstrate that for the first contour, when the flow is swirled to 50% of the rim speed, the purge flow exits the cavity with less cross flow. This in turn reduces the strength of the passage vortex. However, …


Heat Transfer Study Of A Triple Row Impingement Channel At Large Impingement Heights, Roberto Claretti 2011 University of Central Florida

Heat Transfer Study Of A Triple Row Impingement Channel At Large Impingement Heights, Roberto Claretti

HIM 1990-2015

Advanced cooling techniques are required to increase the Brayton cycle temperature ratio necessary for the increase of the overall cycle's efficiency. Current turbine components are cooled with an array of internal cooling channels in the midchord section of the blade, pin fin arrays at the trailing edge and impingement channels in the leading edge. Impingement channels provide the designer with high convective coefficients on the target surface. Increasing the heat transfer coefficient of these channels has been a subject of research for the past 20 years. In the current study, a triple row impingement channel is studied with a jet …


Effect Of Rib Aspect Ratio On Heat Transfer And Friction In Rectangular Channels, Lucky Vo Tran 2011 University of Central Florida

Effect Of Rib Aspect Ratio On Heat Transfer And Friction In Rectangular Channels, Lucky Vo Tran

HIM 1990-2015

The heat transfer and friction augmentation in the fully developed portion of a 2:1 aspect ratio rectangular channel with orthogonal ribs at channel Reynolds numbers of 20,000, 30,000, and 40,000 is studied both experimentally and computationally. Ribs are applied to the two opposite wide walls. The rib aspect ratio is varied systematically at 1, 3, and 5, with a constant rib height and constant rib pitch (rib-pitch-to-rib-height ratio of 10). The purpose of the study is to extend the knowledge of the performance of rectangular channels with ribs to include high aspect ratio ribs. The experimental investigation is performed using …


Nebraska Summary: S814 New Holland T7.200, Nebraska Tractor Test Lab 2011 University of Nebraska-Lincoln

Nebraska Summary: S814 New Holland T7.200, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data. EXPLANATION OF THE TEST PROCEDURES Purpose The purpose of …


Nebraska Summary: S812 New Holland T7.170, Nebraska Tractor Test Lab 2011 University of Nebraska-Lincoln

Nebraska Summary: S812 New Holland T7.170, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data. EXPLANATION OF THE TEST PROCEDURES Purpose The purpose of …


Nebraska Summary: S796 Massey Ferguson 5475, Nebraska Tractor Test Lab 2011 University of Nebraska-Lincoln

Nebraska Summary: S796 Massey Ferguson 5475, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data. EXPLANATION OF THE TEST PROCEDURES Purpose The purpose of …


Test 1983: Bobcat Ct450, Nebraska Tractor Test Lab 2011 University of Nebraska-Lincoln

Test 1983: Bobcat Ct450, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data. EXPLANATION OF THE TEST PROCEDURES Purpose The purpose of …


Test 1996: Case Ih Magnum 225 T3, Nebraska Tractor Test Lab 2011 University of Nebraska-Lincoln

Test 1996: Case Ih Magnum 225 T3, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data. EXPLANATION OF THE TEST PROCEDURES Purpose The purpose of …


Test 2002a: John Deere 8260r My12, Nebraska Tractor Test Lab 2011 University of Nebraska-Lincoln

Test 2002a: John Deere 8260r My12, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data. EXPLANATION OF THE TEST PROCEDURES Purpose The purpose of …


Test 2015: New Holland T9.560, Nebraska Tractor Test Lab 2011 University of Nebraska-Lincoln

Test 2015: New Holland T9.560, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data. EXPLANATION OF THE TEST PROCEDURES Purpose The purpose of …


Test 1996b: New Holland T7070, Nebraska Tractor Test Lab 2011 University of Nebraska-Lincoln

Test 1996b: New Holland T7070, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data. EXPLANATION OF THE TEST PROCEDURES Purpose The purpose of …


On The Thermodynamics Of Degradation, Mehdi Amir Darehbidi 2011 Louisiana State University and Agricultural and Mechanical College

On The Thermodynamics Of Degradation, Mehdi Amir Darehbidi

LSU Doctoral Dissertations

All materials when subjected to fatigue loading are prone to failure if the number of cycles exceeds a certain level. Prediction of the number of cycles to failure is, therefore, of utmost importance in nearly all engineering applications. The existing methods for evaluating the fatigue life are tedious, expensive, and extremely time consuming as fatigue often takes many thousands to millions of cycles until failure occurs. Therefore, methods that can readily estimate the number of cycles to failure are highly desirable. In this work, innovative solutions to fatigue problems are presented and their practical significance is discussed. The premise of …


Creep Behaviour Of Hand Laminated Glass Reinforced Polymer Composites., Brian Quinn 2011 Department of Manufacturing, Facilities and Biomedical Engineering, Cork Institute of Technology, Cork, Ireland.

Creep Behaviour Of Hand Laminated Glass Reinforced Polymer Composites., Brian Quinn

Theses

The creep behaviour of hand laminated, glass fiber reinforced polyester composites were studied at coupon level, due to the use of similar materials in long term load bearing civil and structural engineering applications. Creep predictions were made by fitting the parameters of several viscoelastic models to experimental creep data as well as two accelerated test methods, time temperature superposition (TTS) and frequency time transformations (FTT). TTS experiments were carried out in a dynamic mechanical analyzer (DMA) in three point bending mode for three types of material systems. Creep compliance master curves representing the linear viscoelastic creep response at reference temperatures …


An Advanced Controller For A Semi-Active Wheelchair Suspension, David J. Smith 2011 California Polytechnic State University, San Luis Obispo

An Advanced Controller For A Semi-Active Wheelchair Suspension, David J. Smith

Master's Theses

An Advanced Controller for a Semi-Active Wheelchair Suspension was designed, built and tested.  The suspension consisted of a Goodyear 1S3-011 air spring, IQ Valves high speed proportional solenoid valve, and a custom made accumulator.  Several controller designs specific to semi-active suspensions were designed and tested.  The controllers investigated were skyhook, acceleration driven damping, and a combined control law employing both a dual and single sensor version.  The implementation of skyhook control suffered performance degradation from the idealization due to particular elements of hardware, however acceleration driven damping showed a marked and statistically significant improvement over skyhook control, in hardware, by …


Effect Of Piezoelectric Actuation On Curved Beams And Single Lap Joints, Calicia Johnson 2011 Louisiana State University and Agricultural and Mechanical College

Effect Of Piezoelectric Actuation On Curved Beams And Single Lap Joints, Calicia Johnson

LSU Master's Theses

Piezoelectric materials have seen a significant usage increase over the past decade. They have been found to be effective as either sensors or actuators in smart structure applications, which allows them to act more as an adaptive system rather than a passive system. Piezoelectric materials are very effective transducers which convert mechanical energy into electrical energy, known as the direct piezoelectric effect or they have the ability to convert electrical energy to mechanical energy, known as the converse piezoelectric effect. The absence of additional mechanical parts, its lightweight and high strength to weight ratio is what make piezoelectric materials so …


The Design And Modification Of A Sputter System For Dc Reactive Sputtering Of Alumina And Zirconia Thin Films, Diane Van Ho 2011 Louisiana State University and Agricultural and Mechanical College

The Design And Modification Of A Sputter System For Dc Reactive Sputtering Of Alumina And Zirconia Thin Films, Diane Van Ho

LSU Master's Theses

Yttria-stabilized zirconia (7% YSZ) is the most used material for thermal barrier coatings (TBCs) to reduce the conductive heat transfer on turbine blades, but it is not resistant to infrared radiation. In order to reduce radiation heat transfer, alternating materials, such as alumina and zirconia, can be used to fabricate multi-layer coatings in which each layer is optimized to reflect a targeted range of wavelength. This research aims to fabricate these multi-layer coatings by reactive magnetron sputtering. Reactive magnetron sputtering is the sputtering of an elemental target in the presence of a reactive gas that will react with the target …


Two-Stage Biaxial Thermomechanical Cycle Of Shape Memory Polymer Based Syntactic Foam, Abraham Michael King 2011 Louisiana State University and Agricultural and Mechanical College

Two-Stage Biaxial Thermomechanical Cycle Of Shape Memory Polymer Based Syntactic Foam, Abraham Michael King

LSU Master's Theses

A shape memory polymer (SMP) is a polymeric material that exhibits shape memory behavior. It can be “programmed” to take on a desired shape and “recovered” to revert back to its original shape. This ability to remember multiple shapes and switch between them with the application of a stimulus from an outside source is very desirable in certain applications. By dispersing glass microspheres in a SMP matrix, a syntactic foam is created that retains much of the shape memory capabilities but has higher strength and lower density than the pure SMP. These characteristics make this material a good candidate for …


Pool Boiling Enhancement Via Micro Ratchets, Lance Austin Brumfield 2011 Louisiana State University and Agricultural and Mechanical College

Pool Boiling Enhancement Via Micro Ratchets, Lance Austin Brumfield

LSU Master's Theses

Nucleate boiling is an attractive method for achieving high heat flux at low superheat temperatures. It is frequently used for industrial applications such as heat exchangers and is being considered to cool advanced central processing units (CPU) which produce heat fluxes on the order of 1 MW/m2 and are becoming increasing less efficient to cool via forced conduction of air. The issues with implementing nucleate boiling as a cooling mechanism lies in the difficulty of quantifying the complex and numerous mechanisms which control the process. A comprehensive nucleate boiling model has yet to be formulated and will required in order …


Gas Turbine Blade Tip And Near Tip Heat Transfer With Film Cooling, Gregory Kramer 2011 Louisiana State University and Agricultural and Mechanical College

Gas Turbine Blade Tip And Near Tip Heat Transfer With Film Cooling, Gregory Kramer

LSU Master's Theses

Gas turbine blade tips experience very high thermal loads due to high temperature combustion gases and tip leakage flows. This leads to the tip region being very susceptible to experiencing failures. To better understand these effects, experiments were performed in a suction-type low speed wind tunnel cascade to determine heat transfer coefficients and film cooling effectiveness distributions on a highly-loaded 2-D gas turbine blade model in the tip and near-tip regions. The blade shape was generated to match the pressure coefficients of the operating turbine blade design. The model featured multiple tip and pressure side film cooling holes and a …


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