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Full-Text Articles in Engineering

Radiation In The Space Environment, Sally Hermansen, Jennifer Shatts Dec 2011

Radiation In The Space Environment, Sally Hermansen, Jennifer Shatts

Aerospace Engineering

No abstract provided.


Aircraft Longitudinal Control Experiment, Dustin Schaff Dec 2011

Aircraft Longitudinal Control Experiment, Dustin Schaff

Aerospace Engineering

This paper describes the design, fabrication, and analysis of an experiment that demonstrates the stability and control system characteristics of an aircraft constrained at the center of gravity in an air flow field. Given a set of basic requirements, the physical system (including the airframe, wings, tail, and mounted ball bearing) was designed, modeled, and manufactured. With the aircraft placed in front of a fan and allowed to rotate freely with the ball bearing, an angular rate sensor and servo motor to the deflect the elevator may be connected to any computer using an analog/digital Data Acquisition (DAQ) device to …


Wind Tunnel Modeling Of Small Electric Uav Power System Performance, Nathan R. Phelps Dec 2011

Wind Tunnel Modeling Of Small Electric Uav Power System Performance, Nathan R. Phelps

Aerospace Engineering

This report details the design and construction of a testing apparatus for characterization of small electric aircraft power systems designed for use in the California Polytechnic State University San Luis Obispo Aerospace Engineering department’s subsonic wind tunnel. This apparatus was constructed and implemented with the goal of determining system and component efficiencies of an entire power system using RC Aircraft components as an analog for systems currently in use in the current generation of small electric UAV’s in service with the US Armed Forces. The goal of these experiments was to determine where improvements in the system architecture can be …


Performance Analysis Of A Variable Conductance Heat Pipe, Herron Arreola Oct 2011

Performance Analysis Of A Variable Conductance Heat Pipe, Herron Arreola

Aerospace Engineering

This report examines the analysis of a donated Boeing variable conductance heat pipe with unknown performance characteristics. These characteristics were found through experimental means by utilizing 14 thermocouples attached to various locations on the heat pipe, the heaters and to the insulation. Although the maximum axial heat transport capability could not be determined due to the limited number of strip heaters available, the maximum radial heat flux capability of the heat pipe was found to be 2.46 W/in2. The experiment also revealed that increasing the input power decreased the burn out inclination angle and that using a coolant …


Constrained Hermite Tls For Mesh-Free Derivative Estimation Near And On Boundaries, Robert A. Mcdonald, Alejandro Ramos Oct 2011

Constrained Hermite Tls For Mesh-Free Derivative Estimation Near And On Boundaries, Robert A. Mcdonald, Alejandro Ramos

Aerospace Engineering

A Taylor series least-squares approach to estimating derivatives on scattered data is extended to include derivative observation or specification. This approach allows improved estimation of derivatives near boundaries as compared with the standard ghost node approach. It also enables a unique method of estimating derivatives in a surface using only surface data.


Considerations For Numerical Modeling Of Inverted Wings In Ground Effects, Graham Doig, Tracie J. Barber Oct 2011

Considerations For Numerical Modeling Of Inverted Wings In Ground Effects, Graham Doig, Tracie J. Barber

Aerospace Engineering

No abstract provided.


Flow Characteristics Of The Renovated Cal Poly 3 X 4 Ft Subsonic Wind Tunnel, Mathew L. Thomas, Dorian V. Pandey, Jason N. Nguyen Sep 2011

Flow Characteristics Of The Renovated Cal Poly 3 X 4 Ft Subsonic Wind Tunnel, Mathew L. Thomas, Dorian V. Pandey, Jason N. Nguyen

Aerospace Engineering

This paper investigates the flow characteristics of the renovated Cal Poly 3 x 4 ft subsonic wind tunnel. The IFA 300 constant-temperature anemometer along with a cross-plane X-wire dual-sensor probe was used to measure the mean velocity and turbulence intensity of the tunnel flow and part of the turbulent boundary layer at one section of the tunnel. Because of the malfunction of one channel of the IFA 300, only one wire of the dual sensor probe was calibrated for the measurements. The probe was then placed in a streamlined probe holder mounting on the traverse inside the wind tunnel. The …


Mission Performance Considered As Point Performance In Aircraft Design, Robert A. Mcdonald Sep 2011

Mission Performance Considered As Point Performance In Aircraft Design, Robert A. Mcdonald

Aerospace Engineering

The cruise or loiter performance of an aircraft is intimately tied to its wing loading and its thrust-to-weight ratio. Paradoxically, mission performance is often not considered when these fundamental aircraft parameters are determined in conceptual design. In this paper, the traditional constraint diagram is extended to include contours of range or endurance parameter. These performance metrics represent the mission-performance capability of the aircraft without sizing the aircraft to a particular mission. This gives the designer an immediate and intuitive understanding of the tradeoff between the point and mission performance of the aircraft. The potential freedom for the designer to choose …


Analysis And Design Of A Propulsion System Trade Study Tool For A Boeing 376 Series Communications Satellite, Kevin Dunk Jul 2011

Analysis And Design Of A Propulsion System Trade Study Tool For A Boeing 376 Series Communications Satellite, Kevin Dunk

Aerospace Engineering

No abstract provided.


3d Cfd On An Open Wheel Race Car Front Wing In Ground Effects, Thomas A. Price Jul 2011

3d Cfd On An Open Wheel Race Car Front Wing In Ground Effects, Thomas A. Price

Aerospace Engineering

The purpose of the report is to investigate the ability of the Fluent 6.3 k-ε Realizable turbulence model with standard wall functions to model the flow around the front wing of Cal Poly’s 2008 Formula SAE car. The three primary areas of interest are ground effects, the wing wheel interaction, and the wing tip vortices. Fluent was successful at modeling the increase suction from the ground effects, and the upwash due to the wing tip vortices. The results also displayed how the high pressure region in front of the tire propagates forward and interacts with the pressure distribution around the …


Comparison Of A High Purity Germanium Gamma Ray Spectrometer And A Multidimensional Nai(T1) Scintillation Gamma Ray Spectrometer, Greg Stratton Jul 2011

Comparison Of A High Purity Germanium Gamma Ray Spectrometer And A Multidimensional Nai(T1) Scintillation Gamma Ray Spectrometer, Greg Stratton

Aerospace Engineering

This report compares two different gamma ray spectrometers in terms of performance, operation, and apparatus and also investigates the design and integration challenges of using gamma ray spectrometers in space. The first spectrometer is a one-dimensional high purity germanium (HPGe) spectrometer and the second is a multidimensional NaI(Tl) scintillation spectrometer (MGRS). The key results show that the HPGe exhibits 15 to 27 times better energy resolution than the MGRS, but the MGRS is 52 times more sensitive and removes 177 % more of the background radiation.


The Effects Of Damage Arrestment Devices In Composite Plate Sandwiches With Fastener Holes, Mark Anderson, Nancy Hung Choy, Lacey Jones, Rita Kourskaya Jun 2011

The Effects Of Damage Arrestment Devices In Composite Plate Sandwiches With Fastener Holes, Mark Anderson, Nancy Hung Choy, Lacey Jones, Rita Kourskaya

Aerospace Engineering

Composite materials such as a carbon fiber are used in a variety of new technologies including aircraft, spacecraft, and motor vehicles. Carbon fiber has a high strength to weight ratio, a key advantage over other material options. This report discusses the use of composite damage arrestment devices (DADs) in composite sandwich panels with a foam core. There are three different curing cycles tested for the DADs: pressure only, vacuum only, and vacuum with 1000 lbs of pressure. Using a Tetrahedron Heat Press to cure the composite specimen and an Instron Machine to perform tensile testing, data was collected for each …


Composite I-Beam Fabrication And Testing In Response To 14th Annual Sampe Bridge Competition, Kodi Rider, Niño Noel Las Piñas, Hans Mayta Jun 2011

Composite I-Beam Fabrication And Testing In Response To 14th Annual Sampe Bridge Competition, Kodi Rider, Niño Noel Las Piñas, Hans Mayta

Aerospace Engineering

Composites are a type of material that generally combines two materials yielding mechanical properties that are different than its constituent parts. These constituents are classified as either a fiber or a matrix. The objective of this project is to create a carbon-fiber composite I-beam that meets the specifications of the SAMPE student bridge competition. The I-beam consists of carbon fiber unidirectional and woven laminas, as well as aluminum honeycomb and high density polystyrene foam to stiffen the structure. The bridge contest rules limit the dimensions and weight of the bridge. The cross-section must be within 4 inches x 4 inches …


Thermal Analysis Of The Cubesat Cp3 Satellite, Jonas Friedel, Sean Mckibbon Jun 2011

Thermal Analysis Of The Cubesat Cp3 Satellite, Jonas Friedel, Sean Mckibbon

Aerospace Engineering

Due to inconsistencies found in the on-orbit thermal data from the CubeSat CP3 satellite between 2007 and 2011, further analysis is performed on a larger number of data from August 2010 through April 2011, aiming to find an explanation for the overall increasing measured temperatures and shortening peak periods. Therefore, the satellite power data as well as orbital anomalies are analyzed leading to the conclusion that the satellite was temporarily (January – March 2011) orbiting with significantly increased sun exposure causing the higher temperatures. The shortened temperature peak periods are explained by alternating albedo values as the main influence in …


Determination Of The Surface Boundary Layer Using A Quadrotor, Andrew Haviland Jun 2011

Determination Of The Surface Boundary Layer Using A Quadrotor, Andrew Haviland

Aerospace Engineering

Wind velocity data was taken by a quadrotor UAV using accelerometers, gyroscope, and a barometer. Data was taken at different altitudes over a single position to determine the boundary layer at the surface of the earth. The data taken was compared to the results from numerical methods to determine if this is a practice application for a quadrotor. A few weeks before the test was set to get underway, the quadrotor suffered a very hard crash while testing the GPS and altitude hold function and wasn’t able to completely recover from it. Theoretical results and experiment proposal are covered.


An Analysis Of Stabilizing 3u Cubesats Using Gravity Gradient Techniques And A Low Power Reaction Wheel, Erich Bender Jun 2011

An Analysis Of Stabilizing 3u Cubesats Using Gravity Gradient Techniques And A Low Power Reaction Wheel, Erich Bender

Aerospace Engineering

The purpose of this paper is to determine the feasibility of gravity gradient stabilizing a 3U CubeSat and then using a miniature reaction wheel to further increase stability characteristics. This paper also serves as a guide to understanding and utilizing quaternions in attitude control analysis. The analytical results show that using 33 centimeter booms and 400 gram tip masses, a 3U CubeSat will experience a maximum of 6 degrees of angular displacement in yaw and pitch, and less than .5 degrees of angular displacement in the nadir axis. A .120 kilogram miniature reaction wheel developed by Sinclair Interplanetary was introduced …


Electric Aircraft Propulsion Test Rig Design & Fabrication, Ryan Mayer, Brian Kubicki, Bradley Rodriguez, Austin Harris, David Caudle Jun 2011

Electric Aircraft Propulsion Test Rig Design & Fabrication, Ryan Mayer, Brian Kubicki, Bradley Rodriguez, Austin Harris, David Caudle

Aerospace Engineering

An electric aircraft propulsion test rig was designed and fabricated to predict thrust, torque and battery discharge profiles for an electric aircraft. The original unit was purchased from ElectraFlyer and included the DC brushless motor, carbon fiber propeller, charger, electronic controller and lithium polymer batteries. Various components were constructed and purchased in order to fabricate the optimal test rig apparatus. This apparatus allows for simultaneous measurement of the torque and thrust of the system through the use of a biaxial sensor. The test rig also measures system voltage and current, which allows the user to determine the discharge profile of …


An Investigation Of Dynamic Soaring And Its Applications To The Albatross And Rc Sailplanes, Christopher J. Lee Jun 2011

An Investigation Of Dynamic Soaring And Its Applications To The Albatross And Rc Sailplanes, Christopher J. Lee

Aerospace Engineering

Dynamic soaring is a technique used by the sea bird the Albatross. This technique allows for the bird to stay in the air for extended periods of time with very little effort. Dynamic soaring utilizes the wind gradient on the surface of the ocean to maintain its airspeed. A similar technique is used by RC glider pilots to achieve high speeds by using the shear wind layer on the leeward side of mountain ridges.


An Analysis Of N-Body Trajectory Propagation, Emerson Frees Ii Jun 2011

An Analysis Of N-Body Trajectory Propagation, Emerson Frees Ii

Aerospace Engineering

Trajectories created with n-body orbit models were propagated in geocentric and interplanetary test cases. The n-body models were created in MATLAB® using numerical integration. In the geocentric test case, the n-body codes were compared to a two-body orbit model and to the default HPOP model used in Satellite Tool Kit®. The interplanetary test case compared the n-body model to the HORIZONS ephemeris data from JPL and an equation for ephemeris propagation. Both cases used the same initial positions and velocities and were propagated for the same duration. The results of the analysis showed that while n-body models …


Analysis And Design Of An Affordable High Altitude Rocket System, Brian Cooper Jun 2011

Analysis And Design Of An Affordable High Altitude Rocket System, Brian Cooper

Aerospace Engineering

This paper discusses the design of the Rarefied High-Altitude Zenith Experimental Rocket (RHAZER) which is launched at an altitude of 35 kilometers from a weather balloon. The weather balloon is capable of carrying up to 2 kilograms of payload to this altitude, and the rocket can carry a payload of approximately 150 grams to an altitude of at least 80 kilometers and be recovered safely after landing. It is designed to be aerodynamically stable at its launch point, while using fins to spin-stabilize before it enters the low-pressure upper atmosphere. This system has been designed to be used as an …


Construction Of Naca 66-415 Nlf Composite Wing For Acoustic Turbulence Testing, Scott Sawyer, Sean Stewart Jun 2011

Construction Of Naca 66-415 Nlf Composite Wing For Acoustic Turbulence Testing, Scott Sawyer, Sean Stewart

Aerospace Engineering

A design is developed for a Natural Laminar Flow (NLF) wing, to be used at California Polytechnic State University for acoustic turbulence testing. Composite materials are used to produce high-quality surface finishes necessary for laminar flow. A design for the test apparatus is presented and justified. A manufacturing procedure is proposed for the carbon fiber skin, using Vacuum Resin Infusion (VRI). This procedure is tested on a scaled part with satisfactory results; lessons learned are discovered and integrated into the final manufacturing process. The test section has been fit to the Cal Poly wind tunnel, but full implementation has not …


Development And Design Of A Hovering Controller For Operation In A Dynamic Asteroid Environment, Nicholas Georgiades Jun 2011

Development And Design Of A Hovering Controller For Operation In A Dynamic Asteroid Environment, Nicholas Georgiades

Aerospace Engineering

The project seeks to develop a dynamic model similar to that present near a solar system small body, and to design a controller suggested in other resources that will allow a spacecraft operating in this environment to hover in a fixed location in the relative reference frame of the small body. The paper discusses the derivation of the equations of motion used in the non-linear dynamic model, the design of the controller that will allow the spacecraft to hover, and the development of the control loop that will simulate the spacecraft hovering in the dynamic environment of the asteroid 1999 …


Design, Manufacturing And Testing Of An Environmentally-Green Bipropellant Thruster, Alex Bendoyro, Gabriel Sanchez, Erin Stearns, Phillip Takahashi Jun 2011

Design, Manufacturing And Testing Of An Environmentally-Green Bipropellant Thruster, Alex Bendoyro, Gabriel Sanchez, Erin Stearns, Phillip Takahashi

Aerospace Engineering

This project reviews the design, manufacturing and experimentation process of a green bi-propellant thruster designed to output 5 lbf. The goals were to successfully design, manufacture and test a thruster, while discovering the complications that arise through out the complete design process of a green thruster. The thruster was successfully designed using ideal rocket equations and the design was successfully confirmed using CFD and FEA. Manufacturing of the thruster was fully planned and revealed mild flaws in thruster design. For example some features were not manufacturable to the exact measurements desired. Testing of the engine gave results inconsistent with expected …


Design, Fabrication, And Testing Of An Electromagnetic Rail Gun For The Repeated Testing And Simulation Of Orbital Debris Impacts, Jeff Maniglia, Jordan Smiroldo, Alex Westfall, Guy Zohar Jun 2011

Design, Fabrication, And Testing Of An Electromagnetic Rail Gun For The Repeated Testing And Simulation Of Orbital Debris Impacts, Jeff Maniglia, Jordan Smiroldo, Alex Westfall, Guy Zohar

Aerospace Engineering

An Electromagnetic Railgun (EMRG) was designed, built, and tested, capable of firing a projectile a 1 gram projectile at 650 m/s muzzle velocity. The EMRG utilizes an injector, a high voltage power supply, a capacitor bank, inductors and rails. The injector fires 2300 psig Nitrogen gas into the system to provide an initial velocity. The high voltage power supply charges the capacitor bank. The capacitor bank discharges the electric potential built up through the projectile while inside the rails in order to create the EMRG’s force. The inductors are used to pulse form the capacitor bank in order to get …


Study Of The Effect Of Different Lay-Up Methods On The Composite Mechanical Characteristics, Veronica Cuevas, Walter Ely Salguero Jun 2011

Study Of The Effect Of Different Lay-Up Methods On The Composite Mechanical Characteristics, Veronica Cuevas, Walter Ely Salguero

Aerospace Engineering

The purpose of this experiment is to investigate and understand composite structures and the effect of different layup methods on the composite structure, particularly a composite I-beam. One must learn the procedure on how to build the composite I-beam and put it together then build the final composite I-beam and enter the I-beam in the 14th Annual Society for the Advancement of Material and Process Engineering (SAMPE) Student Bridge Contest. The competition will be held May 25th, 2011 in Long Beach, CA. The I-beam was entered in the competition and placed 4th out of 5. The …


Hybrid Rocket Based Combined Cycle Test Rig Design, Construction, And Testing, Mark Costa, Matthew Handfelt Jun 2011

Hybrid Rocket Based Combined Cycle Test Rig Design, Construction, And Testing, Mark Costa, Matthew Handfelt

Aerospace Engineering

No abstract provided.


Development Of A Laboratory Experiment To Simulate Upper-Stage Rocket Explosions, Timothy J. Price May 2011

Development Of A Laboratory Experiment To Simulate Upper-Stage Rocket Explosions, Timothy J. Price

Aerospace Engineering

This report is a summary of the senior project entitled Development of a Laboratory Experiment to Simulate Upper-Stage Rocket Explosions. The goal of the experiment was to recreate a NASA experiment which used aluminum soft drink cans to approximate the shape of an Ariane third stage rocket. The cans were placed in a vacuum chamber and fired upon with a projectile from a light gas gun. The resulting debris was collected and analyzed allowing several conclusions to be made regarding the behavior or rocket breakups and the formation of space debris. In lieu of a light gas gun, energy drink …


Conical Probe Calibration And Wind Tunnel Data Analysis Of The Channeled Centerbody Inlet Experiment, Samson Siu Truong Apr 2011

Conical Probe Calibration And Wind Tunnel Data Analysis Of The Channeled Centerbody Inlet Experiment, Samson Siu Truong

Aerospace Engineering

For a multi-hole test probe undergoing wind tunnel tests, the resulting data needs to be analyzed for any significant trends. These trends include relating the pressure distributions, the geometric orientation, and the local velocity vector to one another. However, experimental runs always involve some sort of error. As a result, a calibration procedure is required to compensate for this error. For this case, it is the misalignment bias angles resulting from the distortion associated with the angularity of the test probe or the local velocity vector. Through a series of calibration steps presented here, the angular biases are determined and …


Scale Modeling Of Cessna 172, Chee-Woon Kim Mar 2011

Scale Modeling Of Cessna 172, Chee-Woon Kim

Aerospace Engineering

This report describes how the scale-model aircraft can be built when the Reynolds number is out of range for using dynamic similitude method. Due to lack of time and budget for designing an actual model for testing, Cessna 172 was used to calculate the size of the temporary scale-model aircraft. The method that was used for this project was matching aerodynamic coefficients such as drag coefficient or lift coefficient of the prototype and the model. Based on this method, the takeoff distance, landing distance and the rate of climb of the model came out to be 218 ft, 91 ft …


Two Element Linear Strength Vortex Panel Method, Clifton A. Cox Mar 2011

Two Element Linear Strength Vortex Panel Method, Clifton A. Cox

Aerospace Engineering

A linear strength vortex panel method was developed to predict the Cp and Cl for a lifting two element airfoil. The linear strength vortex panel method was first validated against thin airfoil theory and experimental data for a single NACA 2412 airfoil. At 2 degrees angle of attack, the linear strength vortex panel method predicted a Cl of about 0.49. Experimental data and thin airfoil theory gave Cl estimations of 0.45 and 0.22 respectively. The Matlab code was then modified to accept a two element airfoil. The two key modifications were the separation of the two …