# Aerospace Engineering Commons™

## All Articles in Aerospace Engineering

1,336 full-text articles. Page 1 of 31.

2014 Northeastern University

#### Experimental Heat Transfer Coefficients And Friction Factors In A Rib-Roughened Leading-Edge Cooling Cavity Of A Gas Turbine Airfoil, Peter Jacob Hagan

##### Mechanical Engineering Master's Theses

A gas turbine airfoil contains multiple coolant passageways. These passages usually have rib roughened wall surfaces in order to increase the heat transfer from the blade to the cooling air. Auxiliary power and compressed air is very valuable in a gas turbine, therefore low pumping power requirements are crucial. The thermal performance of three different coolant channel geometries with three different rib sizes was investigated. Heat transfer calculations were performed for Reynolds numbers ranging from 6,000 to 40,000. The performance characteristics were calculated through the use of the convective heat transfer coefficient and the friction factor. In this ...

2013 California Polytechnic State University

#### Computational And Experimental Comparison Of A Powered Lift, Upper Surface Blowing Configuration, Jay M. Marcos

##### Master's Theses and Project Reports

In the past, 2D CFD analysis of Circulation Control technology have shown poor comparison with experimental results. In Circulation Control experiments, typical results show a relationship between lift coefficient, CL, vs blowing momentum coefficient, Cμ. CFD analysis tend to over-predict values of CL due to gridding issues and/or turbulence model selection. This thesis attempted to address both issues by performing Richardson’s Extrpolation method to determine an acceptable mesh size and by using FLUENT’s 2-equation turbulence models. The experimental results and CAD geometry were obtained from Georgia Tech Research Institute for comparison with the CFD analysis.

The study ...

2013 California Polytechnic State University

#### Modification Of A Low Cost Vacuum Chamber For Use With An Electromagnetic Railgun, Jason M. Bertels

##### Aerospace Engineering

This report details the design and manufacture of modifications to a low cost vacuum chamber intended for railgun operations. These modifications intend to increase the functionality of the chamber and enable the modeling of high velocity impacts in a space. The original vacuum chamber was constructed primarily from polyvinyl chloride to meet the low cost design constraints, which limits pressures obtainable to the low vacuum region (760 Torr to 2 Torr). Modifications include construction of a space-saving storage rack, replacement of external door supports, installation of an internal guide rail, and installation of electrical feedthroughs.

Light Curve Generation For Satellites In Geostationary Orbits, 2013 California Polytechnic State University

#### Light Curve Generation For Satellites In Geostationary Orbits, Kimberly Andersen

##### Aerospace Engineering

This research were conducted at California Polytechnic State University San Luis Obispo throughout the Winter, Spring, and Fall quarters of 2013. The data presented in this paper was taken on the night of October 20, 2013 at the Cal Poly San Luis Obispo Astronomical Observatory and was reduced using IRAF software available on campus. This report describes the results of an observation of two bright XM geostationary satellites and the steps taken to get to those results. The average magnitude values of the XM-1 and XM-2 satellites were 13.753±0.007 and 14.015±0.007 respectively. The magnitude ...

Set-Up Of Digital Image Correlation Apparatus, 2013 Purdue University

#### Set-Up Of Digital Image Correlation Apparatus, German A. Parada, Michael Sangid

##### The Summer Undergraduate Research Fellowship (SURF) Symposium

Digital Image Correlation (DIC) is a valuable and customizable experimental technique employed to analyze localized strain regions on materials by tracking the displacement of points on the surface of the studied material under applied stress. To investigate materials behavior, it is vital to correctly set-up the DIC apparatus so work has been done to ready the equipment to start measurements on two distinct projects. On the first project, the fatigue crack behavior of a high-strength aluminum alloy will be studied by cyclic loading, testing necessary for the safe design of aircraft parts utilizing this novel alloy. DIC will be carried ...

Advanced Visualization Techniques Of Hot-Jet Combustion Of Lean And Ultra-Lean Substances, 2013 Purdue University

#### Advanced Visualization Techniques Of Hot-Jet Combustion Of Lean And Ultra-Lean Substances, Timothy I. Machin, Li Qiao

##### The Summer Undergraduate Research Fellowship (SURF) Symposium

Research has been conducted on ignition of natural gas as a potential replacement for fossil fuels. A reason natural gas is not widely used and adapted is because of the harmful emissions created when combusted in rich mixtures, but if the gas can be burned at a lean or ultra-lean equivalence ratio, these emissions can be reduced or even eliminated. One method of burning lean and ultra-lean substances is by use of hot-jet ignition. This method ignites the substance near its combustion temperature, reducing the harmful emissions. This method is not yet fully understood, and so research must be done ...

High-Order Shock Capturing For Computational Aeroacoustics, 2013 Purdue University

#### High-Order Shock Capturing For Computational Aeroacoustics, Samuel Otto, Gregory Blaisdell

##### The Summer Undergraduate Research Fellowship (SURF) Symposium

Jet noise is not only an annoyance to passengers and communities near airports, it is a major contributor to hearing loss in veterans who served on aircraft carriers, as well as a significant limiting factor for the growth of commercial airlines. High-fidelity large eddy simulation (LES) is an important tool for analyzing and predicting jet noise; however the utilized non-dissipative high order finite difference schemes produce instabilities at shock waves. Schemes for capturing shock waves, however, are more dissipative and do a poor job preserving turbulent structures and acoustic waves. To maximize the strengths of both approaches, hybrid methods utilize ...

Interaction Model Of Functions In The National Airspace System, 2013 Purdue University

#### Interaction Model Of Functions In The National Airspace System, Nathan F. Koerschner, Steven J. Landry

##### The Summer Undergraduate Research Fellowship (SURF) Symposium

The National Airspace System (NAS) is comprehensively described by five functions derived from big-picture goals: (1) conflict detection and resolution, (2) controlling aircraft states, (3) traffic flow management, (4) controlling passenger states, and (5) controlling company resources. It can be reasonably assumed that these functions interact in some way; this interaction is currently unknown. A model of the entire NAS would be helpful in discovering these interactions, yet no such comprehensive model exists. To address this problem an agent-based state-based model was created in MATLAB. To date, only functions (1) and (2) were implemented. Running the model shows that there ...

Validation Of Long-Fiber Thermoplastic Composite Models, 2013 Purdue University

#### Validation Of Long-Fiber Thermoplastic Composite Models, Christian A. Vuong, Megan Kinney, Michael Sangid

##### The Summer Undergraduate Research Fellowship (SURF) Symposium

With increased pressure to reduce energy consumption, long-fiber reinforced thermoplastic composites (LFTs) are of interest to aerospace and automotive industries due to their light weight in combination with other desirable mechanical properties and ease of manufacturing to replace common materials such as aluminum and magnesium. However, the performance of LFTs is highly dependent on microstructural variables such as fiber length and orientation, which are heavily influenced by the manufacturing process. Accurately predicting these factors would allow for more rapid advances in LFTs by reducing the experiments needed for certification and decreasing expenses. While models that serve this purpose exist, the ...

The Stability And Control Of The Single Track Vehicles, 2013 Purdue University

#### The Stability And Control Of The Single Track Vehicles, Shyngys Karimov, Martin Corless

##### The Summer Undergraduate Research Fellowship (SURF) Symposium

Bicycles, motorcycles and scooters are all examples of the single track vehicles. The dynamics of the single track vehicle involve many degrees of freedom and various modes which govern its performance, making a complicated and interesting research topic. Motorcycle in motion can roll, yaw, and steer about the steering axis. It has three main modes which determine the motion and stability of it, they are weave, capsize, and wobble. The motorcycle performance is limited by the behavior of its modes, and if even one of the modes becomes unstable, the vehicle will roll over, and crash. The goal of this ...

Remote Sensing Using Signals Of Opportunity, 2013 Purdue University

#### Remote Sensing Using Signals Of Opportunity, Alibek Yertay, James L. Garrison

##### The Summer Undergraduate Research Fellowship (SURF) Symposium

Today, there are more than eight thousand satellites in space. Therefore, Radio Frequency (RF) signals broadcast from satellites can be accessed from almost every point on the earth. There will be number of satellites available at most points on earth with different frequency bands. These satellite signals can be used for remote sensing, therefore software that visualizes footprints of satellites and shows characteristics of every satellite available at any point would be useful in determining which signals are available for reflectometry, method where direct satellite signals and reflected satellite signals are received and compared for analysis of certain area. There ...

Testing Of Gelled And Neat Hypergolic Propellants, 2013 Purdue University

#### Testing Of Gelled And Neat Hypergolic Propellants, Bhuvi Swarna Nirudhoddi, Timothee Pourpoint

##### The Summer Undergraduate Research Fellowship (SURF) Symposium

Hypergolic propellants (hypergols) are propellants that ignite shortly after contact. They omit the requirement of an ignition system, making hypergolic engines simple, reliable and capable of being throttled several times. These advantages make them desirable for deep space missions. However, the applications are severely limited by their toxicity and reactivity. In an effort to increase the safety of manufacturing, shipping, and storing, these propellants can be combined with different gelling agents. The focus of this project is to build an optically accessible combustion chamber pressurized at 200 psi to compare the performance of gelled and neat Monomethyl Hydrazine (MMH) and ...

Direct Simulation Monte Carlo Simulation Toolkit For Equilibrium (0d) And Planar Couette Flow (1d), 2013 Purdue University

#### Direct Simulation Monte Carlo Simulation Toolkit For Equilibrium (0d) And Planar Couette Flow (1d), Austin I. Saragih, Alina A. Alexeenko

##### The Summer Undergraduate Research Fellowship (SURF) Symposium

Visualized simulation tool of Direct Simulation Monte Carlo (DSMC) is essential in aeronautical engineering and gas dynamics, by presenting information that can educate engineers and scientists to preliminarily understand the molecular gas dynamics and direct simulation of gas flows. Two educational tools and models are described for rarified gas flows and simulated particle collisions. A 0-Dimensional DSMC in approach to translational equilibrium was developed to simulate the speed distribution over time and the comparison between the final distribution and the Maxwell-Boltzmann distribution. A 1-Dimensional DSMC for Planar Couette flow was also developed to calculate the number of strikes of the ...

2013 McMaster University

#### Fluid Structure Interaction Of A Duckbill Valve, Jing Wang

##### Open Access Dissertations and Theses

This thesis is concerned with a theoretical and experimental investigation of a duckbill valve (DBV). Duckbill valves are non-return valves made of a composite material, which deforms to open the valve as the upstream pressure increases. The head-discharge behavior is a fluid-structure interaction (FSI) problem since the discharge depends on the valve opening that in turn depends on the pressure distribution along the valve produced by the discharge. To design a duckbill valve, a theoretical model is required, which will predict the head-discharge characteristics as a function of the fluid flow through the valve and the valve material and geometry ...

2013 California Polytechnic State University

#### Attitude Estimation For A Gravity Gradient Momentum Biased Nanosatellite, Arash Mehrparvar

##### Master's Theses and Project Reports

Attitude determination and estimation algorithms are developed and implemented in simulation for the Exocube satellite currently under development by PolySat at Cal Poly. A mission requirement of ±5˚ of attitude knowledge has been flowed down from the NASA Goddard developed payload, and this requirement is to be met with a basic sensor suite and the appropriate algorithms. The algorithms selected in this work are TRIAD and an Extended Kalman Filter, both of which are placed in a simulation structure along with models for orbit propagation, spacecraft kinematics and dynamics, and sensor and reference vector models. Errors inherent from sensors, orbit ...

Towards Real-Time, On-Board, Hardware-Supported Sensor And Software Health Management For Unmanned Aerial Systems, 2013 Carnegie Mellon University

#### Towards Real-Time, On-Board, Hardware-Supported Sensor And Software Health Management For Unmanned Aerial Systems, Johann Schumann, Kristin Y. Rozier, Thomas Reinbacher, Ole J. Mengshoel, Timmy Mbaya, Corey Ippolito

##### Silicon Valley Campus

Unmanned aerial systems (UASs) can only be deployed if they can effectively complete their missions and respond to failures and uncertain environmental conditions while maintaining safety with respect to other aircraft as well as humans and property on the ground. In this paper, we design a real-time, on-board system health management (SHM) capability to continuously monitor sensors, software, and hardware components for detection and diagnosis of failures and violations of safety or performance rules during the flight of a UAS. Our approach to SHM is three-pronged, providing: (1) real-time monitoring of sensor and/or software signals; (2) signal analysis, preprocessing ...

Towards Real-Time, On-Board, Hardware-Supported Sensor And Software Health Management For Unmanned Aerial Systems, 2013 Carnegie Mellon University

#### Towards Real-Time, On-Board, Hardware-Supported Sensor And Software Health Management For Unmanned Aerial Systems, Johann Schumann, Kristin Y. Rozier, Thomas Reinbacher, Ole J. Mengshoel, Timmy Mbaya, Corey Ippolito

##### Ole J Mengshoel

Unmanned aerial systems (UASs) can only be deployed if they can effectively complete their missions and respond to failures and uncertain environmental conditions while maintaining safety with respect to other aircraft as well as humans and property on the ground. In this paper, we design a real-time, on-board system health management (SHM) capability to continuously monitor sensors, software, and hardware components for detection and diagnosis of failures and violations of safety or performance rules during the flight of a UAS. Our approach to SHM is three-pronged, providing: (1) real-time monitoring of sensor and/or software signals; (2) signal analysis, preprocessing ...

Multiple Twinning And Variant-Variant Transformations In Martensite: Phase-Field Approach, 2013 Iowa State University

#### Multiple Twinning And Variant-Variant Transformations In Martensite: Phase-Field Approach, Valery I. Levitas, Arunabha M. Roy, Dean L. Preston

##### Aerospace Engineering Publications and Papers

A phase-field theory of transformations between martensitic variants and multiple twinning within martensitic variants is developed for large strains and lattice rotations. It resolves numerous existing problems. The model, which involves just one order parameter for the description of each variant-variant transformation and multiple twinnings within each martensitic variant, allows one to prescribe the twin interface energy and width, and to introduce interface stresses consistent with the sharp interface limit. A finite-element approach is developed and applied to the solution of a number of examples of twinning and combined austenite-martensite and martensite-martensite phase transformations (PTs) and nanostructure evolution. A similar ...

2013 California Polytechnic State University

#### A Study Of The Collisional Evolution Of Orbital Debris In Geopotential Wells And Geo Disposal Orbits, Christina R. Diaz

##### Master's Theses and Project Reports

This thesis will present the effects of the orbital debris evolution in two key areas: the geosynchronous disposal orbit regime known as “graveyard” and the two geopotential wells found in 105◦ W and 75◦ E longitude bins. After developing a GEO specific orbit propagator for NASA Johnson Space Center’s Orbital Debris Of- fice, collisions were simulated throughout these regimes using a low velocity breakup model. This model considered the effects of perturbations particularly non-spherical Earth effects (specifically sectorial and zonal harmonics), lunar effects, third body effects and solar radiation pressure effects. The results show that CDPROP does well in ...

2013 California Polytechnic State University

#### Design, Fabrication And Test Of An Operationally Responsive Aircraft With Niirs Evaluated Imager, Colin Burt

##### Master's Theses and Project Reports

Unmanned Aerial Systems (UAS) are a growing asset. Currently UAS are on the cutting edge with resources being spent developing the capabilities mostly for military use. This project is intended to create a system for non-defense customers. Specifically, the Operationally Responsive Aircraft (ORA) will appeal to academic institutions, individual consumers, future customers new to the UAS industry, as well as anybody trying to get airtime for custom sensors.

The system developed in this project utilizes dual aluminum external payload bays attached to a ParkZone Radian aircraft. Each external payload bay can contain approximately 500 $\text{cm}^3$, with a height ...