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Articles 1 - 13 of 13
Full-Text Articles in Engineering
Oxider To Fuel Ratio Shift Compensation Via Vortex Strength Control In Hybrid Rocket Motors, Max W. Francom
Oxider To Fuel Ratio Shift Compensation Via Vortex Strength Control In Hybrid Rocket Motors, Max W. Francom
All Graduate Theses and Dissertations, Fall 2023 to Present
Hybrid motors have existed as a hypothetical propulsion system for decades in a wide range of upper stage rocket motors due to their simple, robust, non-toxic, and versatile nature. However, inherent to hybrids is Oxidizer to Fuel ratio (O/F) shift over time, which results in performance losses for the majority of the rocket’s lifetime. The purpose of this study is to develop a hybrid rocket motor capable of manipulating O/F at will, resulting in an engine which eliminates the undesirable effects of O/F shift. By developing and refining a numerical simulation, a novel injector system, and an open-loop control scheme, …
Existing Methods For Monitoring Power Autotransformers, Nurali Berdiyorovich Pyrmatov, Dilafruz Rustamjon Qizi Abdullabekova
Existing Methods For Monitoring Power Autotransformers, Nurali Berdiyorovich Pyrmatov, Dilafruz Rustamjon Qizi Abdullabekova
Technical science and innovation
autotransformers, methods, diagnostics, efficiency, monitoring.Particular attention is given to analyzing the gas composition of transformer oil, which is a sensitive indicator of various defects such as thermal breakdown and heating. In addition, methods based on the measurement of external magnetic field strength are discussed. This technique provides a unique opportunity to detect magnetic anomalies associated with possible defects in the structural components of the transformer. The article emphasizes that successful monitoring requires an integrated approach, combining different techniques. The authors analyze the advantages and limitations of each method and offer practical recommendations for integrating these methods into maintenance systems. In …
A Study Of Wings With Constant And Variable Sweep For Aerodynamic Efficiency In Inviscid Flow, Bruno Moorthamers
A Study Of Wings With Constant And Variable Sweep For Aerodynamic Efficiency In Inviscid Flow, Bruno Moorthamers
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Wing sweep has been studied by industry and academia since the pioneering days of aviation for both high-speed and low-speed applications. In transonic and supersonic flight regimes it serves to delay the onset of compressibility effects and decrease wave drag. In subsonic conditions, flying wing designs sweep back the main lifting surface in such a way that it can be used for longitudinal stability and control, to allow for the elimination of a traditional empenage. This is desirable because it can decrease the aerodynamic drag. Sweep can also be seen in nature in the wings of birds and fins of …
Air Navigation And Covid-19: Atm Efficiency In Pandemic Crisis, Fabio Lourenco Carneiro Barbosa
Air Navigation And Covid-19: Atm Efficiency In Pandemic Crisis, Fabio Lourenco Carneiro Barbosa
Graduate Student Works
The coronavirus crisis effects on aviation in 2020 are currently well-documented. Nonetheless, the widely registered low traffic due to the crisis does not necessarily lead to increased air navigation efficiency. Thus, the present work, developed to fulfill the program outcomes for the Master of Science in Aeronautics, Air Traffic Management (ATM) specialization, aimed to investigate what was the impact of the COVID-19 crisis on air navigation efficiency in Brazil. This research question was addressed through a quantitative, nonexperimental, observational approach with two parallel branches, designed to answer two sub-questions. For the first, regarding what was the impact of the crisis …
Competitiveness Of Hybrid Electric Aircraft On Short Range Scheduled Flights, Johannes Anton, Hans-Joachim K. Ruff-Stahl
Competitiveness Of Hybrid Electric Aircraft On Short Range Scheduled Flights, Johannes Anton, Hans-Joachim K. Ruff-Stahl
Hans-Joachim Ruff-Stahl
Hybrid electric aircraft are expected to enter the small regional aircraft market within the next two decades. The aim of this study was to investigate if a hybrid electric passenger aircraft with 50 seats can be competitive against the established 100 seat aircraft on short range scheduled flights. The Embraer EMB 145 and EMB 190 regional jets were chosen as benchmarks for that market. A hypothetical hybrid version of the EMB 145 with increased fuel efficiency was tested on a cost per available seat mile (CASM) basis. The t tests confirmed significant (p < 0.05) competitiveness of the hybrid version, while in contrast the conventional 50-seater was significantly more expensive compared to the 100seat aircraft. This indicates that hybrid aircraft could enter the short haul market with a competitive advantage, even against the established 100 seat regional jets.
Competitiveness Of Hybrid Electric Aircraft On Short Range Scheduled Flights, Johannes Anton, Hans-Joachim K. Ruff-Stahl
Competitiveness Of Hybrid Electric Aircraft On Short Range Scheduled Flights, Johannes Anton, Hans-Joachim K. Ruff-Stahl
International Journal of Aviation, Aeronautics, and Aerospace
Hybrid electric aircraft are expected to enter the small regional aircraft market within the next two decades. The aim of this study was to investigate if a hybrid electric passenger aircraft with 50 seats can be competitive against the established 100 seat aircraft on short range scheduled flights. The Embraer EMB 145 and EMB 190 regional jets were chosen as benchmarks for that market. A hypothetical hybrid version of the EMB 145 with increased fuel efficiency was tested on a cost per available seat mile (CASM) basis. The t tests confirmed significant (p < 0.05) competitiveness of the hybrid version, while in contrast the conventional 50-seater was significantly more expensive compared to the 100seat aircraft. This indicates that hybrid aircraft could enter the short haul market with a competitive advantage, even against the established 100 seat regional jets.
Improving The Efficiency Of Wind Farm Turbines Using External Airfoils, Shujaut Bader
Improving The Efficiency Of Wind Farm Turbines Using External Airfoils, Shujaut Bader
Masters Theses
Wind turbine efficiency typically focuses on the shape, orientation, or stiffness of the turbine blades. In this thesis, the focus is instead on using static fixed airfoils in proximity to the wind turbine to control the airflow coming out of the turbine. These control devices have three beneficial effects. (1) They gather air from “higher up” where the air is moving faster on average (and therefore has more kinetic energy in it). (2) They throw the used (and slowed down air) downwards. This means that any turbines in the wind farm behind the lead turbines do not get “stale” air. …
Optimization Methodology For Cvt Ratio Scheduling With Consideration Of Both Engine And Cvt Efficiency, Steven Beuerle
Optimization Methodology For Cvt Ratio Scheduling With Consideration Of Both Engine And Cvt Efficiency, Steven Beuerle
Masters Theses
A transmission ratio schedule is developed to optimize the fuel consumption for an automotive continuously variable transmission (CVT) connected to an internal combustion engine (ICE). Although the optimal operating line (OOL) generated from an engine brake specific fuel consumption (BSFC) map can be used to generate a CVT ratio schedule that yields maximum engine efficiency, it was found that OOL-based CVT ratio scheduling does not necessarily offer the best fuel economy because optimal CVT efficiency does not always correspond to OOL tracking. To develop a CVT ratio schedule that can offer the best fuel economy, a novel ratio-scheduling methodology is …
Computational Fluid Dynamics Is Key To Better Flying Aircraft, Nihad E. Daidzic
Computational Fluid Dynamics Is Key To Better Flying Aircraft, Nihad E. Daidzic
Aviation Department Publications
No abstract provided.
Modeling And Test Of The Efficiency Of Electronic Speed Controllers For Brushless Dc Motors, Clayton R. Green
Modeling And Test Of The Efficiency Of Electronic Speed Controllers For Brushless Dc Motors, Clayton R. Green
Master's Theses
Small electric uninhabited aerial vehicles (UAV) represent a rapidly expanding market requiring optimization in both efficiency and weight; efficiency is critical during cruise or loiter where the vehicle operates at part power for up to 99% of the mission time. Of the four components (battery, motor, propeller, and electronic speed controller (ESC)) of the electric propulsion system used in small UAVs, the ESC has no accepted performance model and almost no published performance data. To collect performance data, instrumentation was developed to measure electrical power in and out of the ESC using the two wattmeter method and current sense resistors; …
Parametric Scramjet Analysis, Jongseong Choi
Parametric Scramjet Analysis, Jongseong Choi
Electronic Theses and Dissertations
The performance of a hypersonic flight vehicle will depend on existing materials and fuels; this work presents the performance of the ideal scramjet engine for three different combustion chamber materials and three different candidate fuels. Engine performance is explored by parametric cycle analysis for the ideal scramjet as a function of material maximum service temperature and the lower heating value of jet engine fuels. The thermodynamic analysis is based on the Brayton cycle as similarly employed in describing the performance of the ramjet, turbojet, and fanjet ideal engines. The objective of this work is to explore material operating temperatures and …
Space Station 2.0: A Public-Private Model For International Space Exploration, Donovan Torgerson, Josh Berk, Jeremy Straub, Anders Nervold
Space Station 2.0: A Public-Private Model For International Space Exploration, Donovan Torgerson, Josh Berk, Jeremy Straub, Anders Nervold
Jeremy Straub
The international community’s USD$150 billion (€113.94 billion) investment in the International Space Station (ISS) has produced a fraction of the scientific value that was anticipated. This paper presents a concept for how to prevent this problem from occurring for humanity’s next space station project referred to herein as Space Station 2.0. For Space Station 2.0, a research style acquisition program for acquiring modular Space Station components could be used or it could be administered as a commercial facility with international space agencies leasing space for research and other purposes, such as furnished habitat space. Customers may pay a mooring fee …
Optimizing The Efficiency Of A Multi-Stage Axial-Flow Compressor: An Application Of Stage-Wise Optimization, Shawn A. Miller
Optimizing The Efficiency Of A Multi-Stage Axial-Flow Compressor: An Application Of Stage-Wise Optimization, Shawn A. Miller
Theses and Dissertations
The development of jet engines has become an integral part of maintaining air superiority. In order to achieve the most advanced engine, research has turned to traditional optimization methods to aid in creating new engine designs. To develop simplified mathematical models representative of the engine, the engine can be separated into its components. A jet engine has three major elements, the compressor, combustion chamber and turbine. This research attempts to make an initial analysis of a two stage compressor to determine values of blade angles and spacing to chord ratios for both stages that produce the highest possible efficiency for …