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Stress Analyses of a Windowed Bomb for Battery Failure Experiments
Get PDFLithium-ion batteries (LIBs) are one of the most prevalent modern energy storage technologies. Their relatively high energy density makes them attractive for many applications, such as electric vehicles, spacecraft, and smart phones. Unfortunately, these batteries also can pose a serious threat to consumers when they undergo thermal runaway (TR).In the current study, an old flame speed vessel is being retrofitted into a state-of-the-art LIB failure test experiment to evaluate the potential hazards of these incidents. The retrofitted vessel will be utilized to perform experiments wherein LIBs are heated to failure to induce TR. The vent gases and micro/nano particles released will be captured and analyzed using gas chromatography-mass spectroscopy (GC-MS) and electron microscopy methods, respectively. The experiment will also include high-speed video analysis with the potential for additional optical diagnostic capabilities. An important component of retrofitting the vessel was the removal of fans that were previously utilized to generate turbulence and sealing the openings the fans occupied. An aluminum cover plate was designed that can withstand the elevated pressures and temperatures that could be caused by LIB TR in the vessel. The design procedure consisted of material selection, seal design, analytical 1D stress analyses, and two versions (semi-infinite and FEA approaches) of 1D transient heat transfer analyses. The final design is a 0.5�����thick circular plate made of Al 6061 with a face-seal, silicone O-ring. The experiment has not been fully designed at the time of publishing this report, but design of all subsystems is nearing completion and the remaining future work has been identified. Check-out experiment testing is anticipated in the summer of 2022
U.S. Budget Woes
Get PDFThe Congressional Budget Office���s latest economic and budget projections from ���An Update to the Budget and Economic Outlook: 2024 to 2034��� are worrisome, to say the least. The CBO projects large and persistent federal government deficits through 2034, and with no end in sight. In the Fall 2024 issue of PERCspectives on Policy, Dennis Jansen and Somali Ghosh Sinha take a historical look at the debt held by the public as a percent of GDP from pre-World War II onwards, analyze how increased government spending during the Covid-19 pandemic differed from war-era deficits, and discuss the causes behind ever-increasing government outlays
X-Band Phased-Array Transmitter Design for Space Solar Power System
Get PDFAmidst a global energy crisis, many organizations are investigating innovative ways of producing renewable energy. Current methods of scalable renewable energy have significant drawbacks preventing energy providers from making a complete conversion to more sustainable methods. Recent research discusses the economic and technical viability of a novel method of solar power generation that aims to negate the primary issues plaguing solar energy���s capabilities. Space-based solar power is where solar power collection satellites wirelessly distribute solar energy to earth, eliminating losses from atmospheric absorption and clouds. Additionally, the satellites would be positioned at such an altitude that they are exposed to the sun 24 hours per day. The enticing prospect of a continuous source of renewable energy justifies further investigation if the requisite technology is available, and if its benefits outweigh the costs. This thesis describes the phased-array microwave transmitter for wirelessly beaming the energy 2 to the target on earth. The transmitter is composed of over 1 billion microwave patch antennas, organized into a grid of subarrays called tiles. Each 400 antenna tile group is equipped with a phase locked loop to generate the X-band signal, programmable phase shifters to modify beam direction, power amplifiers to drive antennas, and a control circuit, all designed in TSMC���s 40 nm CMOS technology. The control circuit provides the interface for a specialized calibration algorithm that utilizes power transmission data to continuously calibrate tiles for correcting beam aim and minimizing beam width. The performance results of each designed system are compiled into a Python model of the complete transmitter design. Results of the model show that the transmitter is capable of distributing well over 1 GW of power to a 2 km by 2 km rectenna array. These findings encourage further research and development in this field to accurately determine the economic and technical viability of a full space-based solar power system and provide design suggestions to innovate on the transmitter design with more modern technologies
Mineral Recovery from Concentrated Brine
Get PDFThe separation of minerals from brine has been a long-standing problem in industry. Although brine contains valuable minerals, most of it is discharged to oceans because separating the minerals is not currently economical. Although several different processes exist and are currently employed for separating minerals in brine, they utilize large amounts of solvents and precipitation agents. This creates the potential for increased process safety risks and negative environmental impacts. The content contained within this report explores the viability of elutriation for separating minerals from brine. Because it is a physical separation process, this method does not use any solvents or precipitation agents. Elutriation takes advantage of the different densities of precipitated salts from brine by passing the salts through an upward flowing column of saturated brine. This causes less-dense salts to be swept away, while heavier salts remain in the bottom of the column. This technique has been employed in other industries, but has not been applied in the context of mineral-extraction from brine on an industrial level. Contained within this thesis are a series of experiments analyzing different crystallization methods, evaluating density-based separation by elutriation, and finally developing a prototype elutriation column. The only minerals studied in these experiments are potassium chloride and sodium chloride, but future work should be extended to more profitable compounds, such as lithium salts, and other abundant salts, such as magnesium salts
