Browsing by Author "Schubert, Peter J."

Now showing 1 - 10 of 48
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    Abandoned Mine Voids for Pumped Storage Hydro
    (Juniper Publishers, 2019) Schubert, Peter J.; Izadian, Afshin; Wheeler, J. W.; Electrical and Computer Engineering, School of Engineering and Technology
    Pumped Storage Hydro (PSH) is geographically limited but can expand greatly if abandoned subsurface coal mines are leveraged for the lower reservoir. Such lands are already permitted, generally less desirable, and found in regions eager for job creation. Vertical stacking of the upper and lower reservoirs is an efficient use of the land. Water can be raised by electric pumps as part of energy arbitrage; however, water can also be raised with Hydraulic Wind Turbines. HWTs are far less costly than traditional electric turbines, and start-up at lower wind speeds - thereby extending their geographic range. The HWT masts can serve double duty as tent poles to support translucent architectural fabric over the surface lake. This prevents evaporation and ingress of wildlife, and provides an interior space useful for non-electric revenue, such as aquaculture and greenhouses. Water cycled through the system can, in some cases, supplement local sources. Seepage through water tables replenishes clean water. Subsurface water is cool and can be circulated through server farms in data centers which represents a potential revenue source that can be started up well in advance of the primary energy storage operation. Combined, these factors bring an innovative solution to site selection, design, and engineering for PSH which promises accelerated commissioning and permitting, and low-cost operation. The bottom line for communities in Coal Country is more jobs and cheaper power.
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    Actinide concentration from lunar regolith via hydrocyclone density separation
    (Longdom Publishing, 2021) Schubert, Peter J.; Kindomba, Eli; Hantzis, Connor; Conaway, Adam; Yeong, Haoyee; Littell, Steven; Palani, Sashindran; Electrical and Computer Engineering, Purdue School of Engineering and Technology
    Beneficiation of regolith to concentrate the high-density ore fraction from the gangue can be accomplished through momentum transfer methods, such as ballistic deflection or cyclonic separation. This study explores the extraction of actinide-bearing minerals from lunar regolith based on the difference in apparent density between thorium-bearing minerals (e.g. ThO2 ρ=10) from silicates (e.g. SiO2 ρ=2.65). Thorium content in lunar regolith ranges from single-digit parts per million (ppm) to as high as 60 ppm. Concentrating thorium-bearing minerals is a required first step in the preparation of fission fuels for a nuclear reactor in which all of the radioactive operations are performed 380,000 km from the Earth’s biosphere. After comparison with ballistic deflection, cyclone separation with a non-volatile fluid carrier was chosen for further study. With sieving to separate particles by size, such a hydrocyclone can be used to efficiently separate the dense fraction from the lighter minerals. Design equations were used to fabricate an at-scale apparatus using water, iron particles, and glass beads as simulants. Results show the ability to effect a 2 to 5.4 % increase in dense fraction concentration each pass, such that 95% concentration requires between 50 and 100 passes, or a cascade of this many apparatuses. The selection of a suitable fluid for safe and low-mass transport to the Moon is part of a techno-economic analysis of the cost and infrastructure needed to produce highly-purified thorium minerals on the lunar surface.
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    Administrative Policy for Stochastic Democracy
    (AIAA, 2018-09) Schubert, Peter J.; Sommer, Joe; Electrical and Computer Engineering, School of Engineering and Technology
    Prior studies of stochastic democracy have compared it to other forms of governance, demonstrated how to scale up or scale down as population changes, and developed an algorithm for start-up on Day 1. Left unanswered is the administrative policy for regulating the statutes developed by the legislative bodies. As the aim of stochastic democracy is design of a corruption-resistance form of managing human affairs the implementation of the activities of the government must also be robust against undue influence, bribery, and abuse of power. Decision-makers in a stochastic democracy by design cannot be “career” politicians, however, the bureaucrats of the government agencies or departments or ministries are advantageously retained across the changes in the legislative bodies. This quality invites corruption, the answer to which cannot be simply to apply oversight or policing. In this paper is developed an integrated structure which supplants the Byzantine-derived corporate-style hierarchy. Seven principles are applied to the bureaucracy and their integration and practice described herein as administrative policy, the principles being: transparency of regulatory process; not-less-than time limits; disclosure of change proposers; inclusion of economic externalities; open debate and notices of intent; chairmanship and participant selection; and periodic but stochastic changes in the number of agencies at each level of governance. This latter enforces either consolidation or expansion, within high and low limits, the re-organization of which will shuffle the reporting structure of the regulatory bureaucracy and disrupt entrenched habits and possible corrupting schemes. When complementing the legislative functions this work rounds-out the formation of a corruption-resistant, scalable form of truly representative governance for space habitats and societies of arbitrary size.
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    Analysis of a Novel SPS Configuration Enabled by Lunar ISRU
    (2015) Schubert, Peter J.; Pinto, Sheylla Monteiro; Pires, Bruna Caroline; do Nascimento, Moises; Barks, Edward; Nderitu, Jonathan; Goncalves, Gabriel; Tokmo, Fatih; Department of Engineering Technology, School of Engineering and Technology
    Architectures for space-based solar power using in situ resource utilization (ISRU) of space materials can greatly reduce earth launch mass and can enable geometric capacity growth. These two factors allow the potential for low cost power generation after development of an in-space infrastructure. A collection of extraction and processing methods designed for lunar operation provides for large volumes of low cost solar panels. With abundant panels a novel configuration for solar power satellites (SPS) is possible which avoids many of the challenges of existing designs. The so-called "tin can" SPS has no moving parts. It includes integral thermal radiators. Station-keeping requirements are minimal. Structural integrity is designed-in so that balance of plant mass is minimal. In this work the architecture and infrastructure supporting the tin can SPS is developed to support rapid construction and deployment. Performance estimates for the SPS are provided regarding heat and energy balance, and specific mass requirements.
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    Antenna Arrangement Verification for Low Sidelobe Levels
    (IEEE, 2019) Kragt Finnell, Abigail J.; Schubert, Peter J.; Electrical and Computer Engineering, School of Engineering and Technology
    Space-to-earth Wireless Power Transfer (WPT) in large scale will not be allowed unless the side lobe levels (SLL) can be reduced many orders of magnitude lower than the current technology allows. In particular, high SLL could potentially interfere with aircraft communications around the beam, while the area inside the beam would necessarily be a no-fly zone, similar as over nuclear power plants. To overcome this, the transmitting antenna must be cleverly designed and controlled. In this work, independent validation of the layout, spacing, and envelope arrangement of a design first proposed in 2016 is performed and presented. This design involves a hexagonal design with a triangular antenna element arrangement and a spacing of 0.8 wavelengths using the Dolph-Chebychev beam profile. While this has been shown to produce -240 dB SLL in the AWR Design Environment already, it will now be analyzed using the MATLAB Phased Array System Toolbox. The design will also be investigated on a smaller scale, with the potential for use in other applications, including the powering of low orbit weather balloons or unmanned aerial vehicles (UAVs). The possibility of very low SLL would be transformational in these and other WPT applications, including space solar power, and could greatly benefit humanity and the environment.
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    Baseload Fission Reactor for Lunar Operations
    (IAF, 2020) Schubert, Peter J.; Doshi, Jeel; Munyala Kindomba, Eli; Bhaskaran, Amal; Conaway, Adam; Electrical and Computer Engineering, School of Engineering and Technology
    Breakout performance for human operations will be realized once there are MW-class continuousoperation fission reactors on the Moon. This is likely to be realized only when there is a means for producing fissile fuel from ISRU resources, such as lunar thorium, because of the concerns associated with earth-launch of radioactive materials. Space is pervaded by gamma rays which produce neutrons upon interaction with beryllium. When moderated by graphite said neutrons can be captured by the thorium nucleus, which transmutes into protactinium, which further decays into the U-233 isotope of uranium. U233 is an excellent source because the radioactive byproducts of spent fuel are short-lived, becoming safe after about 80 years. Thorium dioxide (ThO2 or thoria) is much more dense than the regolith average, and is found in concentrations exceeding those on earth in certain craters of the north Near Side, possibly because of the excavation of rich subsurface deposits due to meteorite impacts. Using jaw crushers and trommels made of durable lightweight metals a lunar mining operation can extract hundreds of kilograms of thoria by using a polymeric adaptation of a Wilfley sorting table laid along the sloped wall of a crater. An acid leach process can be used to remove intermediate protactinium from further neutron irradiation, which will decay to U-233. After processing the transmutated urania (UO2) is packed into fuel rods for a first-generation lunar fission reactor. The same gamma rays and beryllium will initiate a controlled chain reaction to provide baseload power. A Brayton cycle generator can produce power in a manner similar to the small modular reactor concept in development for terrestrial loads. With power outputs in the range of 10 to 60 MW, a single reactor can provide heat and power for a sizeable human base plus mining operations, as well as electromagnetic launchers to deliver payloads into orbit. Water harvested from polar craters can be shipped to any orbit. Greenhouses on the Moon can become the breadbasket to the Solar System. Electric power can be delivered over transmission lines, or via wireless power transfer to a variety of loads such as rovers, orbiting spacecraft, and even multiple habitats. With no nuclear materials needing to be launched from the earth’s surface, and with relatively short-lived hot waste, this is a pathway to the long duration settlement of the Moon.
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    Bio-Hydrogen Refueling Station
    (Office of the Vice Chancellor for Research, 2016-04-08) Schubert, Peter J.
    Hydrogen fuel cell cars are now available for lease and for sale. Renewable hydrogen fuel can be produced from water via electrolysis, or from biomass via gasification. Electrolysis is powerhungry with high demand from solar or wind power. Gasification, however, can be energy selfsufficient using a recently-patented thermochemical conversion technology known as Indirectly- Heated Pyrolytic Gasification. I-HPG produces a tar-free syngas from non-food woody biomass. This means the balance of plant can be small, so the overall system is economical at modest sizes. This makes it possible to produce renewable hydrogen from local agricultural residues; sufficient to create distributed refueling stations wherever there is feedstock. This work describes the specifics of a novel bio-hydrogen refueling station whereby the syngas produced has much of the hydrogen extracted with the remainder powering a generator to provide the electric power to the I-HPG system. Thus the system runs continuously. When paired with another new technology, moderate-pressure storage of hydrogen in porous silicon, there is the potential to also power the refueling operation. Such systems can be operated independently. It is even possible to design an energy self-sufficient farm where all electric power, heat, and hydrogen fuel is produced from the non-food residues of agricultural operations. No water is required, and the carbon footprint is negative, or at least neutral.
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    Brownfield remediation powered by renewable energy
    (Office of the Vice Chancellor for Research, 2016-04-08) Schubert, Peter J.
    Subsurface contaminant plumes are a plague upon the earth. Some 1900 plumes remain after the go-fast atom bomb projects of the Cold War. Countless gasoline station sites dot our cities, leaching heavy metals and chlorinated solvents into drinking water. Superfund-type cleanup is so expensive that many sites languish while toxins continue to spread throughout the ecosystem. Federal funding for remediation research stopped 15 years ago. The only solution now is to move bad soil from one location to another. New advances in stem cell manipulation offer promise to clean up solvent-infused earth with a minimum of excavation at greatly reduced costs. Dielectrophoresis is the means by which polar molecules, in a matrix having a different dielectric constant, can be made to migrate along electric field gradients. A unique configuration called “pills and pillars” facilitates remediation of solvents. Electric field gradients originating in the deeply-driven “pillars” motivate solvents molecules towards the slightly-buried “pill”. When powered by renewable sources, such as solar panels, contaminants within a 1000 m3 volume can be concentrated within a 1 m3 volume at the pill, and then removed for disposal in a certified toxic waste repository. The pills and pillars are easily extracted for removal to a new site every 40 days. The solar panels are man-portable so that a single capital expenditure of a truckmounted kit can serve multiple sites simultaneously, and sequentially. The low labor overhead, the greatly reduced excavation, and the re-use of hardware contribute to make this novel method of brownfield remediation far cheaper than traditional, presently-available methods. Computer simulations including both vadose zone diffusion (natural spreading out) and drift via dielectrophoresis, demonstrate the effectiveness of this approach. The next research step is to build a benchtop model to validate the simulation model, followed by field trials with partners in the environmental remediation industry.
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    Capstone Design Project Experience: Lunar Ice Extraction Design
    (American Society for Engineering Education, 2016-01) Zusack, Steven Anthony; Patil, Raveena; Lachenman, Sean; Johnson, Chanel Antoinette; Schubert, Peter J.; Department of Engineering Technology, School of Engineering and Technology
    A group of senior undergraduate students came together as part of a non-traditional capstone design project. The assignment was to take part in the NASA RASC-AL competition and required adjustment to the class curriculum. Two examples are that a direct point of contact from the customer would not be possible as there is no specific person at NASA meant to act as the customer and the submission deadline was after the semester concluded. The students were all from the mechanical engineering department and had a fascination with space technology but came from vastly different demographic backgrounds representing multiple spheres of diversity. This diversity brought unique and unexpected approaches to the project. The project required close interaction of the group throughout and after the semester to accomplish a very difficult goal: the design of a full scale lunar ice extraction facility capable of running autonomously and producing at least 100 metric tonnes of ice per year. The operational plan is to be accompanied by a detailed budget and launch plans to begin taking effect in 2025. Having no experience working with one another prior to this project, the group was required to quickly develop a productive team ethos to address such a large challenge. The aim of this study is to assess the outcomes and reactions during a project from a diverse group of students attempting to complete an unusual capstone design. Accompanying this are pre-, intra-, and post-project surveys to assess effectiveness of the group on key project issues. The primary research questions to answer are: does the perception of the group regarding effectiveness positively correlate with the feelings of ownership of the project and feelings that the individual students’ passions are being considered. Further, because the competition is staged and set to go on the full academic year, the students are interviewed regarding plans on continuing the project beyond the current semester when the majority of the team will have graduated.
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    Complete Hydrogen Storage System by ISRU
    (AIAA, 2018) Schubert, Peter J.; Electrical and Computer Engineering, School of Engineering and Technology
    New technologies make it possible to build in space a complete hydrogen storage system using ISRU methods and techniques. Hydrogen can be stored in a solid-state form on the surface atoms of high surface area matrices such as those of porous silicon. Silicon is abundant in regolith and can be purified using a purely mechanical means which results in particulates in the scale range of tens of nanometers. Reagents used to porosify these nano-particles can be regenerated thermally to essentially eliminate the need for resupply from earth. Catalysts are needed to divide dihydrogen gas into atomic hydrogen for solid-state adsorption and to mediate the temperatures and pressures of charge and discharge into ranges easily achievable with simple equipment. Recent research has identified the utility of non-platinum group catalyst materials which are widespread on the moon. Rapid discharge, needed for propulsion, is possible with infra-red illumination at wavelengths which pass through pure silicon but are absorbed by the silicon-hydrogen bond. Such IR emitters can be fabricated by embossing of silica and additive manufacturing of metals. Control and power electronics can be fabricated using a patented process designed for space operations, and built on either silicon or silicon carbide substrates derived from regolith. Bringing these five technologies together for the first time allows a system which can be fed with moderate pressure gaseous hydrogen at moderate temperatures, stored for long durations with minimum loss, then released upon demand across a wide range of controllable rates. Such a system can displace the need for cryogenic hydrogen storage. Being suitable to bottom-up fabrication using only in-space materials makes this a “green” ISRU technology to store hydrogen for fuel cells, rocket engines, and chemical processes.