Matching Items (17)
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- All Subjects: Aerospace
- Creators: Mechanical and Aerospace Engineering Program
- Creators: Redkar, Sangram
- Resource Type: Text
Description
In nearly all commercially successful internal combustion engine applications, the slider crank mechanism is used to convert the reciprocating motion of the piston into rotary motion. The hypocycloid mechanism, wherein the crankshaft is replaced with a novel gearing arrangement, is a viable alternative to the slider crank mechanism. The geared hypocycloid mechanism allows for linear motion of the connecting rod and provides a method for perfect balance with any number of cylinders including single cylinder applications. A variety of hypocycloid engine designs and research efforts have been undertaken and produced successful running prototypes. Wiseman Technologies, Inc provided one of these prototypes to this research effort. This two-cycle 30cc half crank hypocycloid engine has shown promise in several performance categories including balance and efficiency. To further investigate its potential a more thorough and scientific analysis was necessary and completed in this research effort. The major objective of the research effort was to critically evaluate and optimize the Wiseman prototype for maximum performance in balance, efficiency, and power output. A nearly identical slider crank engine was used extensively to establish baseline performance data and make comparisons. Specialized equipment and methods were designed and built to collect experimental data on both engines. Simulation and mathematical models validated by experimental data collection were used to better quantify performance improvements. Modifications to the Wiseman prototype engine improved balance by 20 to 50% (depending on direction) and increased peak power output by 24%.
ContributorsConner, Thomas (Author) / Redkar, Sangram (Thesis advisor) / Rogers, Bradley (Committee member) / Georgeou, Trian (Committee member) / Arizona State University (Publisher)
Created2011
Description
This work describes the numerical process developed for use of rocket engine nozzle ejectors. Ejector nozzles, while applied to jet engines extensively, have not been applied to rockets, and have great potential to improve the performance of endoatmospheric rocket propulsion systems. Utilizing the low pressure, high velocity flow in the plume, this secondary structure entrains a secondary mass flow to increase the mass flow of the propulsion system. Rocket engine nozzle ejectors must be designed with the high supersonic conditions associated with rocket engines. These designs rely on the numerical process described in this paper.
ContributorsGibson, Gaines Sullivan (Author) / Wells, Valana (Thesis director) / Takahashi, Timothy (Committee member) / Barrett, The Honors College (Contributor) / Mechanical and Aerospace Engineering Program (Contributor)
Created2014-05
Description
The purpose of this project is to determine the feasibility of a water tunnel designed to meet certain constraints. The project goals are to tailor a design for a given location, and to produce a repeatable design sizing and shape process for specified constraints. The primary design goals include a 1 m/s flow velocity in a 30cm x 30cm test section for 300 seconds. Secondary parameters, such as system height, tank height, area contraction ratio, and roof loading limits, may change depending on preference, location, or environment. The final chosen configuration is a gravity fed design with six major components: the reservoir tank, the initial duct, the contraction nozzle, the test section, the exit duct, and the variable control exit nozzle. Important sizing results include a minimum water weight of 60,000 pounds, a system height of 7.65 meters, a system length of 6 meters (not including the reservoir tank), a large shallow reservoir tank width of 12.2 meters, and height of 0.22 meters, and a control nozzle exit radius range of 5.25 cm to 5.3 cm. Computational fluid dynamic simulation further supports adherence to the design constraints but points out some potential areas for improvement in dealing with flow irregularities. These areas include the bends in the ducts, and the contraction nozzle. Despite those areas recommended for improvement, it is reasonable to conclude that the design and process fulfill the project goals.
ContributorsZykan, Brandt Davis Healy (Author) / Wells, Valana (Thesis director) / Middleton, James (Committee member) / Barrett, The Honors College (Contributor) / Mechanical and Aerospace Engineering Program (Contributor)
Created2014-05
Description
Wastewater treatment plant (WWTP) utilization of combined heat and power (CHP) systems allows for the efficient use of on-site biogas production, as well as increased annual savings in utility costs. In this thesis, a literature review of six CHP prime mover technologies is presented. Even though there are different prime mover technologies, the main ones currently being implemented in WWTPs are micro turbines, fuel cells and reciprocating engines. These prime mover technologies offer varying efficiencies, installation costs and maintenance requirements. The prime movers are also all in different stages of development, leading some to be more currently-in-use than others in WWTPs. Currently reciprocating engines and micro turbines occupy the largest shares of the CHP in WWTP sector.
This thesis will also go in detail into equations and calculations created for a techno-economic assessment for installation and maintenance of a CHP system at a WWTP. The equations and calculations created here were then utilized with data from a typical WWTP in the Southwestern United States to create an accurate case study. In this case study, a payback of 5.7 years and a net present value of $709,000 can be achieved when the WWTP generates over 2,000,000 m3 of biogas per year and utilizes over 36,000 GJ of natural gas per year.
This thesis will also go in detail into equations and calculations created for a techno-economic assessment for installation and maintenance of a CHP system at a WWTP. The equations and calculations created here were then utilized with data from a typical WWTP in the Southwestern United States to create an accurate case study. In this case study, a payback of 5.7 years and a net present value of $709,000 can be achieved when the WWTP generates over 2,000,000 m3 of biogas per year and utilizes over 36,000 GJ of natural gas per year.
ContributorsRiley, Derall (Author) / Milcarek, Ryan (Thesis director) / Villalobos, Rene (Committee member) / Mechanical and Aerospace Engineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2020-12
Description
The objective of this project is to design an indraft supersonic wind tunnel that is safe and comparatively simple to construct. The processes and methodology of design are discussed. As with every supersonic wind tunnel, the critical components are the nozzle, diffuser, and the means of achieving the pressure differential which drives the flow. The nozzle was designed using method of characteristics (MOC) and a boundary layer analysis experimental proven on supersonic wind tunnels [5]. The diffuser was designed using the unique design features of this wind tunnel in combination with equations from Pope [7]. The pressure differential is achieved via a vacuum chamber behind the diffuser creating a pressure differential between the ambient air and the low pressure in the tank. The run time of the wind tunnel depends on the initial pressure of the vacuum tank and the volume. However, the volume of the tank has a greater influence on the run time. The volume of the tank is not specified as the largest tank feasible should be used to allow the longest run time. The run time for different volumes is given. Another method of extending the run duration is added vacuum pumps to the vacuum chamber. If these pumps can move a sufficient mass out of the vacuum chamber, the run time can be significantly extended. The mounting design addresses the loading requirements which is closely related to the accuracy of the data. The mounting mechanism is attached to the rear of the model to minimize shockwave interference and maximize the structural integrity along the direction with the highest loading. This mechanism is then mounted to the bottom of the wind tunnel for structural rigidity and ease of access.
ContributorsWall, Isaiah Edward (Author) / Wells, Valana (Thesis director) / Kshitij, Abhinav (Committee member) / Mechanical and Aerospace Engineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2020-05
Description
The temperature of exhaust pipes can be dangerous in dry areas where there is a lot of brush. The temperatures of exhaust pipes can reach a high enough temperature to start a fire if touching the dry brush, which ignites around 300°C. The goal of this project was to explore different techniques to limit the possibility of these brush fires. Specifically, different methods were explored to reduce the temperature of the pipe that would be contacting the brush. Fires can begin within seconds of contacting the hot exhaust pipes [10]. This experiment found that of the three options tested: exhaust wrap, heat sink with thermoelectric devices, and high temperature paint, adding a heat shield/sink is the best way to limit the high temperatures from igniting the brush. There was a cooling difference of nearly 100°C when a heat shield/sink was added to the bare pipe. The additional thermal mass as well as the finned heat sinks attached to the heat sink helped dissipate the heat from the pipe and release the waste heat into the surroundings. The increase in surface area in correspondence with forced convection from the surrounding air lowered the temperature of the metal in contact with the dry brush.
ContributorsHodges, Andrew (Author) / Benson, David (Thesis director) / Bocanegra, Luis (Committee member) / Mechanical and Aerospace Engineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2020-05
Description
This project aims to study the relationship between model input parameters and model output accuracy of the Tool for Automation of Computational Aerodynamics of Airfoils (TACAA). The input parameters of study are Mach number and Reynolds number, and inputs are tested through three flight speed regimes and from laminar to turbulent flow. Each of these input parameters are tested for the NACA 0012 and SC-1095 airfoils to ensure that the accuracy is similar regardless of geometric complexity. The TACAA program was used to run all simulation testing, and its overall functionality is discussed. The results gathered from the preliminary testing showed that the spread of variable input data points caused data gaps in the transonic regime results, which provided motivation to conduct further testing within the transonic region for both airfoils. After collecting all TACAA results, data from wind tunnel testing was compiled to compare. The comparison showed that (1) additional testing would be necessary to fully assess the accuracy of the results for the SC-1095 airfoil and (2) TACAA is generally accurate for compressible, turbulent flows.
ContributorsKuang, Joyce (Co-author) / Stickel, Hannah (Co-author) / Wells, Valana (Thesis director) / Duque, Earl (Committee member) / Mechanical and Aerospace Engineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2020-05
Description
During my fourth year at Arizona State University, I enrolled in two capstone projects while working towards my
undergraduate degree in aerospace engineering. The first of the two team projects was an aerospace capstone: Design of
Autonomous Aircraft Systems. The second being a capstone project based out of Arizona State’s design school:
Innovation Space. The purpose of this dual enrollment was to compare and contrast the two product development projects,
in hopes to recommend a course of action to engineers younger than myself who are presented the option of multiple
capstones. This report will elaborate on three areas of engineering design and how they were realized in these projects.
These 3 topics are product development and its effect on design to manufacture, design feature creep, and technical vs
non-technical design. After considering the pros and cons of both capstone projects and their relation to the three main
topics of this report, it was decided that individuals who are motivated to become the best engineers they can be upon
graduating from an undergraduate program, they should find the time to take both capstone courses. Both Design of
Autonomous Aircraft Systems and Innovation Space present opportunities to create new ways of engineering thinking, all
of which will be necessary for an engineer to succeed in his/her first years in industry.
undergraduate degree in aerospace engineering. The first of the two team projects was an aerospace capstone: Design of
Autonomous Aircraft Systems. The second being a capstone project based out of Arizona State’s design school:
Innovation Space. The purpose of this dual enrollment was to compare and contrast the two product development projects,
in hopes to recommend a course of action to engineers younger than myself who are presented the option of multiple
capstones. This report will elaborate on three areas of engineering design and how they were realized in these projects.
These 3 topics are product development and its effect on design to manufacture, design feature creep, and technical vs
non-technical design. After considering the pros and cons of both capstone projects and their relation to the three main
topics of this report, it was decided that individuals who are motivated to become the best engineers they can be upon
graduating from an undergraduate program, they should find the time to take both capstone courses. Both Design of
Autonomous Aircraft Systems and Innovation Space present opportunities to create new ways of engineering thinking, all
of which will be necessary for an engineer to succeed in his/her first years in industry.
ContributorsEll, Samuel Leo (Author) / Hedges, Craig (Thesis director) / Kuhn, Anthony (Committee member) / Industrial, Systems & Operations Engineering Prgm (Contributor) / Mechanical and Aerospace Engineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2019-05
Description
Accurate pointing is essential for any space mission with an imaging payload. The Phoenix Cubesat mission is being designed to take thermal images of major US cities from Low Earth Orbit in order to study the Urban Heat Island effect. Accurate pointing is vital to ensure mission success, so the satellite's Attitude Determination and Control System, or ADCS, must be properly tested and calibrated on the ground to ensure that it performs to its requirements. A commercial ADCS unit, the MAI-400, has been selected for this mission. The expected environmental disturbances must be characterized and modeled in order to inform planning the operations of this system. Appropriate control gains must also be selected to ensure the optimal satellite response. These gains are derived through a system model in Simulink and its response optimization tool, and these gains are then tested in a supplier provided Dynamic Simulator.
ContributorsWofford, Justin Michael (Author) / Bowman, Judd (Thesis director) / Jacobs, Daniel (Committee member) / School of Earth and Space Exploration (Contributor) / Mechanical and Aerospace Engineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05
Description
This paper studies the history and development of ion propulsion systems and survey past, present, and developing technology with their applications to space missions. This analysis addresses the physical design parameters and process that is a part of designing and optimizing a gridded ion thruster. It also identifies operational limits that may be associated with solar-powered ion propulsion systems and posits plausible solutions or alternatives to remedy such limitations. These topics are presented with the intent of reviewing how ion propulsion technology evolved in its journey to develop to today's systems, and to facilitate thought and discussion on where further development of ion propulsion systems can be directed.
ContributorsTang, Justine (Author) / White, Daniel (Thesis director) / Dahm, Werner (Committee member) / Mechanical and Aerospace Engineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05