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Ramjet Combustion Chamber, Paul Cameron Stone 2013 California Polytechnic State University, San Luis Obispo

Ramjet Combustion Chamber, Paul Cameron Stone

Aerospace Engineering

A ramjet combustion chamber is designed and some initial assembly fabrication and test completed as a component of a ramjet graduate project for California Polytechnic State University, San Luis Obispo Supersonic Wind Tunnel. The combustor design is driven by a theoretical model created by a Cal Poly graduate student, Harrison Sykes. Temperature, pressure, and fuel flow will be measured.


The Effects Of Fabrication Methods And Cure Cycle On The Mechanical Properties Of Carbon Fiber Laminate In Tensile And 3-Point Bend Testing, Adriano Agostino 2013 California Polytechnic State University, San Luis Obispo

The Effects Of Fabrication Methods And Cure Cycle On The Mechanical Properties Of Carbon Fiber Laminate In Tensile And 3-Point Bend Testing, Adriano Agostino

Aerospace Engineering

This project was completed at the California Polytechnic State University, San Luis Obispo Aerospace Engineering Structures and Composites Lab during Spring Quarter 2013. The purpose of this project was to research and to gain insight into the effects of fabrication methods and of modifying cure cycles for Newport NB-301 12l 2x2 Twill Weave Carbon Fiber material properties. The two fabrication methods used were autoclave and heat press (compression molding) methods. Each fabrication method used two cure cycles, a recommended cure cycle of 275°F for 1 hour and a modified cure cycle of 250°F for 1.5 hours. The exact product data …


Design And Fabrication Of A Ramjet Engine, Clinton C. Humphrey 2013 California Polytechnic State University, San Luis Obispo

Design And Fabrication Of A Ramjet Engine, Clinton C. Humphrey

Aerospace Engineering

In this report, the design and fabrication of the inlet to a ramjet engine is described. The inlet utilizes a single ramp and single sided three shock internal compression to slow the airflow from supersonic to subsonic speeds while providing maximum stagnation pressure to the combustor. The optimum angle for the inlet ramp is calculated to be 10° and it decelerates the airflow from Mach 3.3019 to Mach 0.5438. The stagnation pressure increases from 150 psi to 4.67 ksi. The material of the inlet is composed primarily of low carbon mild steel to accommodate the high pressure of the inlet.


Feasibility Of Cubesat Formation Flight Using Rotation To Achieve Differential Drag, Skyler M. Shuford 2013 California Polytechnic State University, San Luis Obispo

Feasibility Of Cubesat Formation Flight Using Rotation To Achieve Differential Drag, Skyler M. Shuford

Aerospace Engineering

This paper presents the results of a study conducted to understand the feasibility of CubeSat formation flight. The mechanism for separation and formation studied was differential drag, achieved by rotating the CubeSats to give them different cross-sectional areas. Intuitively, lower altitude orbits provide much higher separation effects. Although the most influential orbital effects occur with maximum and minimum cross-sectional areas, an attitude-controlled and a tumbling CubeSat may provide enough differential drag to meet separation requirements of a mission. Formation flight is possible, but due to the non-linearity of the system, gain scheduling may be the most effective method of long …


Proof Of Concept For Propeller Performance Testing In The Cal Poly Wind Tunnel, Alex N. May, Clayton R. Green, Clinton J. Kirsop, Jason A. Schupp 2013 California Polytechnic State University, San Luis Obispo

Proof Of Concept For Propeller Performance Testing In The Cal Poly Wind Tunnel, Alex N. May, Clayton R. Green, Clinton J. Kirsop, Jason A. Schupp

Aerospace Engineering

The goal of this experiment was to execute a proof of concept for a potential propulsion systems laboratory. During the course of this experiment, a data acquisition system was designed, built, and tested in order to collect data from the Cal Poly 3x4 ft draw-down wind tunnel. By operating a brushless outrunner motor and propeller on the sting mount, data was collected for thrust, torque, RPM, current, voltage, and tunnel velocity. By obtaining data for each of these performance metrics, trends were analyzed to confirm the concept and apparatus was functional. The results of the experiment revealed that the concept …


Nozzle Design For The Supersonic Wind Tunnel Ramjet Attachment, Andrew Michael Carter 2013 California Polytechnic State University, San Luis Obispo

Nozzle Design For The Supersonic Wind Tunnel Ramjet Attachment, Andrew Michael Carter

Aerospace Engineering

This document outlines the concept, design, and manufacturing stages of the nozzle section to the Ramjet Attachment. This project is a subsidiary of the thesis, Baseline Performance of Ramjet Engine”, developed by Harrison Sykes. The nozzle geometry is based off of theoretical calculations using Isentropic and Rayleigh line flow relations for a two-dimensional cross section. The nozzle sees an inlet temperature of 953 degrees Fahrenheit, pressure of 28 psi, and a Mach number of 0.356 after the combustion chamber. The nozzle section is a two foot long converging diverging nozzle to choke and accelerate the flow to achieve an exit …


Redesigned Aerospace Control System Platform For Laboratory Re-Purposing, Ryan W. Moskaluk 2013 California Polytechnic State University, San Luis Obispo

Redesigned Aerospace Control System Platform For Laboratory Re-Purposing, Ryan W. Moskaluk

Aerospace Engineering

This senior project encompasses using an aircraft model in conjunction with the 3' by 4' low speed wind tunnel at Cal Poly San Luis Obispo. The aircraft model is controlled through piezoelectric actuators embedded inside the flexible tail structure via a PID controller. The objective for this project is to demonstrate the effect of tuning the individual PID controller gains with the aircraft model inside the low speed wind tunnel and to create an easy to use graphical user interface for doing so.


Coupled Flow Field Simulations Of Charring Ablators With Nonequilibrium Surface Chemistry, Hicham Alkandry, Iain D. Boyd, Alexandre Martin 2013 University of Michigan

Coupled Flow Field Simulations Of Charring Ablators With Nonequilibrium Surface Chemistry, Hicham Alkandry, Iain D. Boyd, Alexandre Martin

Mechanical Engineering Faculty Publications

This paper describes the coupling of a Navier-Stokes solver to a material response code to simulate nonequilibrium gas-surface interactions. The Navier-Stokes solver used in this study is LeMANS, which is a three-dimensional computational fluid dynamics code that can simulate hypersonic reacting flows including thermo-chemical nonequilibrium effects. The material response code employed in this study is MOPAR, which uses the one-dimensional control volume nite-element method to model heat conduction and pyrolysis gas behavior. This coupling is demonstrated using a test case based on the Stardust sample return capsule. Coupled simulations are performed at three different trajectory conditions. The effects of the …


A New Approach To Light-Weight Ablators Analysis: From Micro-Tomography Measurements To Statistical Analysis And Modeling, Nagi N. Mansour, Francesco Panerai, Alexandre Martin, Dilworth Y. Parkinson, Alastair A. MacDowell, Abdelmoula Haboub, Timothy A. Sandstrom, Tony Fast, Gerard L. Vignoles, Jean Lachaud 2013 NASA Ames Research Center

A New Approach To Light-Weight Ablators Analysis: From Micro-Tomography Measurements To Statistical Analysis And Modeling, Nagi N. Mansour, Francesco Panerai, Alexandre Martin, Dilworth Y. Parkinson, Alastair A. Macdowell, Abdelmoula Haboub, Timothy A. Sandstrom, Tony Fast, Gerard L. Vignoles, Jean Lachaud

Mechanical Engineering Faculty Publications

The morphology characteristics and ablation behavior of a highly porous carbon fiber preform are studied using a combined experimental/numerical approach. Morphological characterization of the three-dimensional structure of the material is performed by hard X-rays synchrotron micro-tomography at the Advanced Light Source of Lawrence Berkeley National Laboratory. The resulting micro-tomography voxels are used to compute geometrical properties of the carbon preform, like porosity, specific surface area and tortuosity, that are otherwise indirectly measured through experimental techniques. The reconstructed volumes are used to build a computational grid for numerical simulations of the fibers' ablation. By modeling the diffusion of oxygen through the …


Volume Averaged Modeling Of The Oxidation Of Porous Carbon Fiber Material, Alexandre Martin 2013 University of Kentucky

Volume Averaged Modeling Of The Oxidation Of Porous Carbon Fiber Material, Alexandre Martin

Mechanical Engineering Faculty Publications

Charring ablators remain the premium choice for space exploration missions that involve atmospheric re-entry. This type of ablative material is composed of a carbon matrix, usually made of fibers, which is then impregnated with a resin. During re-entry, the high heat flux produced by convective heating causes the material to chemically react. First, the resin pyrolyzes, and is vaporized into a gas that travels through the material, and is eventually ejected at the surface. Then, as the temperature rises, the surface of the porous matrix recess through ablative processes. For re-entry conditions typical of space exploration missions, this is mainly …


Flow-Tube Oxidation Experiments On The Carbon Preform Of Pica, Francesco Panerai, Alexandre Martin, Nagi N. Mansour, Steven A. Sepka, Jean Lachaud 2013 University of Kentucky

Flow-Tube Oxidation Experiments On The Carbon Preform Of Pica, Francesco Panerai, Alexandre Martin, Nagi N. Mansour, Steven A. Sepka, Jean Lachaud

Mechanical Engineering Faculty Publications

Oxidation experiments on the carbon preform of a phenolic-impregnated carbon ablator were performed in the NASA Ames ow-tube reactor facility, at temperatures between 700 and 1300 K, under dry air gas at pressures between 103 and 104 Pa. Mass loss, volumetric recession and density changes were measured at different test conditions. An analysis of the diffusion/reaction competition within the porous material, based on the Thiele number, allowed us to identify low temperature and low pressure conditions to be dominated by in-depth volume oxidation. Experiments above 1000 K were found at transition conditions, where diffusion and reaction occur at similar scales. …


Multi-Dimensional Modeling Pyrolysis Gas Flow Inside Charring Ablators, Haoyue Weng, Alexandre Martin 2013 University of Kentucky

Multi-Dimensional Modeling Pyrolysis Gas Flow Inside Charring Ablators, Haoyue Weng, Alexandre Martin

Mechanical Engineering Faculty Publications

Using an ablative thermal/material response code, the importance of three-dimensionality for modeling ablative test-article is addressed. In particular, the simulation of the pyrolysis gas flow inside a porous material is presented, using two different geometries. The effects of allowing the gas to flow out of the side wall are especially highlighted. Results show that the flow inside the test-article is complex, and that the 0D or 1D assumption made in most Material Response (MR) codes might not be valid for certain geometries.


Incorporating Aluminum Honeycomb To Increase Efficiency Of U-Tube Removable Heat Exchanger, Daniel Soto, Daniel Corona 2013 California Polytechnic State University, San Luis Obispo

Incorporating Aluminum Honeycomb To Increase Efficiency Of U-Tube Removable Heat Exchanger, Daniel Soto, Daniel Corona

Aerospace Engineering

This report contains the results of attempting to improve on the results of Scott R. Sawyer and Alan M. L’Esperance research paper “Investigation of Paraffin Wax as an Energy Storage Medium Within a Shell-and-Tube Heat Exchanger.” The overall goal of the paper mentioned was to investigate the usefulness of wax as an energy storage medium. Scott R. Sawyer and Alan M. L’Esperance determined that “the amount of energy that can be released by the paraffin wax back to the airflow reaches a plateau, despite an increase in heating times.” They suggested that by surrounding the airflow tubes of a heat …


Paschen Breakdown In A Co2 Atmosphere, Matthew T. Stumbo 2013 California Polytechnic State University, San Luis Obispo

Paschen Breakdown In A Co2 Atmosphere, Matthew T. Stumbo

Aerospace Engineering

This report observes and analyzes the effect the pressure and gap distance have on the minimum positive breakdown potential between two parallel plate copper electrodes in both air and CO2. Two gap distances, 0.57 cm and 2.44 cm, were used. Paschen Curves generated in air from these distances had a strong positive correlation with a Spearman correlation coefficient of 0.97. Curves generated in CO2 had a Spearman correlation coefficient of 0.87. The strong correlation for both gases verifies Paschen's Law. The minimum breakdown potential in air was 361 ± 2 V at a pressure x gap distance …


Synergistic Effects Of Atomic Oxygen And Ultraviolet Radiation Exposure On Various Spacecraft Materials, Adrian L. Doan 2013 California Polytechnic State University, San Luis Obispo

Synergistic Effects Of Atomic Oxygen And Ultraviolet Radiation Exposure On Various Spacecraft Materials, Adrian L. Doan

Aerospace Engineering

The Aerospace Engineering Space Environments Laboratory at California Polytechnic State University features a ground-based system capable of generating atomic oxygen (AO) and vacuum ultraviolet (VUV) radiation environments, constructed by Max Glicklin in 2012. Experiments using three different spacecraft materials were conducted to test the individual and synergistic effects of these naturally occurring phenomena. Kapton HN functioned as a means to provide initial validation of the presence of AO and VUV radiation. Kapton HN also functioned as a test-fluence standard during testing of two other materials. These materials included aluminized beta cloth, with the non-aluminized side being tested, and Indium-Tin-Oxide (ITO) …


Thermal Vacuum Chamber Operation And Testing, Leila Tebyani 2013 California Polytechnic State University, San Luis Obispo

Thermal Vacuum Chamber Operation And Testing, Leila Tebyani

Aerospace Engineering

The purpose of this senior project is to understand the capabilities of the thermal vacuum chamber in the Space Environments Laboratory at California Polytechnic State University and compare the performance to thermal vacuum chambers used in the aerospace industry. The lowest temperature attained inside the chamber during an experiment at ambient pressure was -33°C. The lowest pressure reached by the vacuum chamber at the time of this project was 5e-5 Torr. This report also yields recommendations for integrating a demonstation of the effects of thermal variation in space on spacecraft components for the class AERO 471. A lit LED can …


Development Of Random Vibration Profiles For Test Deployers To Simulate The Dynamic Environment In The Poly-Picosatellite Orbital Deployer, Steve Furger 2013 California Polytechnic State University, San Luis Obispo

Development Of Random Vibration Profiles For Test Deployers To Simulate The Dynamic Environment In The Poly-Picosatellite Orbital Deployer, Steve Furger

Aerospace Engineering

TestPODs and P-PODs have different structures with different resonant frequencies. This causes a change in the frequency response for CubeSats integrated into TestPODs compared to P-PODs. Adjusted random vibration profiles were developed for TestPODs to simulate the dynamic environment of the P-POD so CubeSats would have a consistent response in both deployers. Testing has shown that, with proper characterization of TestPODs and P-PODs, adjusted profiles can be used for TestPODs to simulate the P-POD dynamic environment.


Fin Flutter Analysis, Richard Bauer, Austin Hardman 2013 California Polytechnic State University, San Luis Obispo

Fin Flutter Analysis, Richard Bauer, Austin Hardman

Aerospace Engineering

This report summarizes the experimental process executed to study fin flutter characteristics. The experiment analyzed the influence of the relationship between structural dynamics and aerodynamics on flutter characteristics. Theoretical models were created in PATRAN/NASTRAN and FinSim for comparison to experimental results and to set the envelope of the physical experiments. The theoretical analysis predicted the occurrence of flutter near Mach 1 or Mach 5. The physical model was constructed of solid aluminum with machined holes for the inertial sensors. Two test runs were completed to collect data on the displacement of the fin in the supersonic wind tunnel. Additionally, the …


Creation And Analysis Of An Electric And Magnetic Model Of A Micro Ion Thruster, Maxwell Bodnar 2013 California Polytechnic State University, San Luis Obispo

Creation And Analysis Of An Electric And Magnetic Model Of A Micro Ion Thruster, Maxwell Bodnar

Aerospace Engineering

This report explores the magnetic and electric fields within the Cal Poly Miniature Xenon Ion (MiXI) Thruster V3 in order to create a comprehensive electric and magnetic model of the plasma chamber to analyze and test the current thruster configurations and changes to the existing thruster. This model is used to analyze the operation and efficiency of the ion thruster and the plasma environment within the plasma chamber. This model explores the ionization and electron collision rates during operation of the thruster to measure the efficiency of the current thruster configuration, also determining the theoretical Isp and thrust of the …


Study Of Natural Composite Materials Square Beam Under Three Point Bending Test, Casey Wu 2013 California Polytechnic State University, San Luis Obispo

Study Of Natural Composite Materials Square Beam Under Three Point Bending Test, Casey Wu

Aerospace Engineering

The purpose of this report is to summarize the findings on three point bending tests to try to find the optimum geometrical shape and layup configuration of a square beam composed of natural composites. The final project was entered into the SAMPE 2013 bridge building competition to compete internationally against other universities in the natural square beam category. The main focus of the bridge project is to compose it entirely of natural occurring fibers and other natural materials to create a “green” beam. The beams in the competition are tested under 3 point bending tests and will be scored based …


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