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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 235 records · Page 13
All sourcesNASA NTRSDOE OSTI
DOE OSTI2015

Determination of the separation efficiencies of a single-stage cryogenic distillation setup to remove krypton out of xenon by using a {sup 83m}Kr tracer method

The separation of krypton and xenon is of particular importance for the field of direct dark matter search with liquid xenon detectors. The intrinsic contamination of the xenon with radioactive {sup 85}Kr makes a significant background for these kinds of low count-rate experiments and has to be removed beforehand. This can be achieved by cryogenic distillation, a technique widely used in industry, using the different vapor pressures of krypton and xenon. In this paper, we present an investigation on the separation performance of a single stage distillation system using a radioactive {sup 83m}Kr-tracer method. The separation characteristics under different operation conditions are determined for very low concentrations of krypton in xenon at the level of {sup 83m}Kr/Xe = 1.9 ⋅ 10{sup −15}, demonstrating, that cryogenic distillation in this regime is working. The observed separation is in agreement with the expectation from the different volatilities of krypton and xenon. This cryogenic distillation station is the first step on the way to a multi-stage cryogenic distillation column for the next generation of direct dark matter experiment XENON1T.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗
NASA NTRS1989

Subminiature infrared detector translation stage

This paper describes a precision subminiature three-axis translation stage used in the GOES Sounder to provide positional adjustment of 12 cooled infrared detectors. Four separate translation stages and detectors are packaged into a detector mechanism which has an overall size of 0.850 x 1.230 x 0.600 inches. Each translation stage is capable of + or - 0.015 inch motion in the X and Y axes and +0.050/-0.025 inch motion in the Z axis with a sensitivity of 0.0002 inches. The function of the detector translation stage allows real time detector signal peaking during Sounder alignment. The translation stage operates in a cryogenic environment under a 10 to the -6th torr vacuum.

Bell, Alan D.↗
NASA NTRS2010

Evaluation of Dual-Launch Lunar Architectures Using the Mission Assessment Post Processor

The National Aeronautics and Space Administrations (NASA) Constellation Program is currently designing a new transportation system to replace the Space Shuttle, support human missions to both the International Space Station (ISS) and the Moon, and enable the eventual establishment of an outpost on the lunar surface. The present Constellation architecture is designed to meet nominal capability requirements and provide flexibility sufficient for handling a host of contingency scenarios including (but not limited to) launch delays at the Earth. This report summarizes a body of work performed in support of the Review of U.S. Human Space Flight Committee. It analyzes three lunar orbit rendezvous dual-launch architecture options which incorporate differing methodologies for mitigating the effects of launch delays at the Earth. NASA employed the recently-developed Mission Assessment Post Processor (MAPP) tool to quickly evaluate vehicle performance requirements for several candidate approaches for conducting human missions to the Moon. The MAPP tool enabled analysis of Earth perturbation effects and Earth-Moon geometry effects on the integrated vehicle performance as it varies over the 18.6-year lunar nodal cycle. Results are provided summarizing best-case and worst-case vehicle propellant requirements for each architecture option. Additionally, the associated vehicle payload mass requirements at launch are compared between each architecture and against those of the Constellation Program. The current Constellation Program architecture assumes that the Altair lunar lander and Earth Departure Stage (EDS) vehicles are launched on a heavy lift launch vehicle. The Orion Crew Exploration Vehicle (CEV) is separately launched on a smaller man-rated vehicle. This strategy relaxes man-rating requirements for the heavy lift launch vehicle and has the potential to significantly reduce the cost of the overall architecture over the operational lifetime of the program. The crew launch occurs first, four days prior to the optimal trans-lunar injection (TLI) departure window. This is done to allow for launch delays in the Altair/EDS launch. During this time, the Orion vehicle is required to conduct orbit maintenance while loitering in low Earth orbit (LEO). The alternative architectures presented aim to eliminate the need for costly orbit maintenance maneuvers while loitering in LEO. In all of the alternative architectures considered, it is assumed that the Altair and Orion vehicles are nominally launched 90 minutes apart, depart the Earth separately, and complete the rendezvous and docking sequence at the Moon. In this lunar orbit rendezvous (LOR) strategy, both the Altair and Orion vehicles will require separate EDS stages, and each will be required to perform lunar orbit insertion (LOI). This has the effect of balancing payload requirements between the two launch vehicles at the Earth. In this case, the overall payload mass is increased slightly, but the increased mission costs could potentially be offset by requiring the construction of two rockets similar in size and nature, unlike the current Constellation architecture. Three dual-launch architecture options with LOR were evaluated, which incorporate differing methodologies for mitigating the effects of launch delays at the Earth. Benefits and drawbacks of each of the dual-launch architecture options with LOR are discussed and the overall mission performance is compared with that of the existing Constellation Program lunar architecture.

Stewart, Shaun M.↗
NASA NTRS1985

Cell Partition in Two Polymer Aqueous Phases

In a reduced gravity environment the two polymer phases will not separate via density driven settling in an acceptably short length of time. It is to be expected that a certain amount of phase separation will take place, however, driven by the reduction in free energy gained when the interfacial area is reduced. This stage of separation process will therefore depend directly on the magnitude of the interfacial tension between the phases. In order to induce complete phase separation in a short time, electric field-induced separation which occurs because the droplets of one phase in the other have high electrophoretic mobilities which increase with droplet size was investigated. These mobilities are significant only in the presence of certain salts, particularly phosphates. The presence of such salts, in turn has a strong effect on the cell partition behavior in dextran-poly (ethylene glycol) (PEG) systems. The addition of the salts necessary to produce phase drop mobilities has a large effect on the interfacial tensions in the systems.

Brooks, D. E.↗
NASA NTRS2004

A New Spin

The trouble was that the shuttle was still under development when that schedule was set. As time went on, the Shuttle had problems with its high pressure turbines, thermal protection tiles, engines, and more. The early launch dates had to be scrapped. NASA Headquarters told us, "We re going to delay your launch two years to allow more time for the Shuttle development to take place. You can slow your development accordingly." Right off the bat, we looked into the celestial mechanics and how they would affect us. The difficulty in launching a spacecraft to Jupiter changes on a year-to- year basis, in a cyclical pattern that repeats about every ten or twelve years. In order to achieve the velocity needed to get from low earth orbit to Jupiter, an upper stage is required in the Shuttle. For the 1982 launch the upper stage was adequate, but it could not provide the velocity we would need in 1984. This meant we would have to separate the Galileo probe from the Galileo orbiter before launch and put each of them on separate Shuttles with separate upper stages. When we told the folks at Headquarters this, they told us, "Okay we'll give you two Shuttle launches."

Casani, John↗
NASA NTRS1993

Membrane Separation Of Nitrogen Tetroxide

Pilot plant reduces N2O4 content to one-hundredth of inlet value. Permeable-membrane process removes nitrogen tetroxide from stream of nitrogen or helium gas. Operates in conjunction with scrubbing process removing N2O4 from He or N2 after He or N2 used as gas blanket in N2O4-storage tank. First stage of separator divided into two steps for efficiency. Permeate from second step of first stage and residue from second stage returned to inlet of first stage. Each module contains spiral-wound interleaved permeable membranes and spacer sheets.

Castro, R. C.↗
NASA NTRS1993

A two-stage virtual impactor for continuous concentration of particles in an aerosol

A two-stage virtual impactor has been designed and fabricated to concentrate aerosol particles. In this impactor, the minor flow from the first stage of the impactor is introduced into the second stage as the primary flow. The cut-point of the impactor is designed to be about 0.3 micron. The sample aerosol is introduced into the impactor at a flow rate of 8.0 atm-l/min and after the two stages of separation, particles are collected into the minor flow of 0.06 atm-l/min with 84 percent efficiency. The tandem arrangement of the two stages increases the concentration of larger particles by a factor of greater than 100. The small size and the low flow rates make the impactor compatible with the sampling requirements of instruments used for the chemical and physical characterization of particles from low-particle number density aerosols. In particular, the high particle concentration factor of the impactor will make it possible to analyze individual particles in real time from aerosols containing less than 10 particles per cft by the mass spectrometric methods developed in our laboratory.

Sinha, M. P.↗
DOE OSTI2018

Optimal Distribution of Centrifuges over Stages in a Cascade for Separating Multicomponent Mixtures of Isotopes

A method of calculating the optimal operating parameters of a centrifuge cascade for separating multicomponent mixtures of isotopes is developed. A computational scheme is proposed for calculating the parameters of a cascade and the distribution of the centrifuges over the stages with a prescribed total number of centrifuges in different variants of optimization. Calculations showing the particulars of optimization and the efficacy of the developed method are presented.

07 ISOTOPE AND RADIATION SOURCES↗
NASA NTRS1960

Ranger Spacecraft

The thermal-control philosophy of the spacecraft currently under development by the Jet Propulsion Laboratory is design by passive means to maintain all components within the tolerances specified by cognizant engineers. Due to the complexity of the configurations, calculations are) of necessity, fairly generalized and final design is based upon tests in an environmental chamber. The Ranger series spacecraft is designed with a basic structure which is common to all models, with additional hardware to suit the individual mission. This basic structure of Rangers A-1 and A-2 is seen as the hexagonal instrument section, the erectable solar panels, the movable antenna, and the omniantenna. The Ranger A-1 and A-2 configuration is for engineering tests and space-exploration, with the scientific instrumentation isolation requirement dictating the spread-out design. The spacecraft stands 12 feet high, weighs 700 to 800 pounds, and has an internal power of 150 watts. Rangers A-3, A-4, and A-5 are designed to rough land a capsule on the moon. For these, a capsule and retrorocket replace the scientific instruments, occupying the space inside the tower structure. The spacecraft must survive many environments. Chronologically they are: 1) Folded configuration inside an aerodynamic shroud on the pad. 2) Thermal flux from shroud aerodynamically heated during boost phase. 3) Coasting up to 30 minutes attached to Agena stage after booster and shroud are separated. 4) Agena stage burning. 5) Coasting and tumbling after separation from Agena until it passes from earth's shadow. 6) Upon reaching sunlight, panels open and begin sun acquisition. 7) Antenna seeks earth after spacecraft locks onto sun. 8) Space phase- "steady state" with vehicle's vertical axis locked on sun, communicating with earth. The philosophy is to design for the sun-acquired mode, making allowances for the transient conditions.

Thostesen, T. O.↗
DOE OSTI2017

Facile Separation of Sr-90, Fe-55, Nb-94, Ni-59,63 with Large Amount of Ca by Controlled pH Precipitation - 17190

it is important to manage low-and intermediate-level radioactive wastes from nuclear power plants due to a permanent disposal. According to the Nuclear Safety and Security Commission (NSSC), among all the regulatory radionuclides, a few radionuclides from the fission products and corrosion products such as Sr-90, Fe-55, Nb-94, Ni-59,63 which emit low-energy x-ray and beta radiation. Thus, it is necessary to separate beta-emitting nuclides individually. For that reason, KAERI has established analytical procedures which can separate Sr-90, Fe-55, Nb-94, Ni-59,63 from radioactive waste samples. However, when radioactive wastes contain large amount of Ca (above 300 mg), it is not easy to recover the target radionuclides because high concentration of Ca has a strong influence on the effective analyses. In order to combat this problem, there was an attempt to make the precipitate as CaF{sub 2} by using hydrofluoric acid. However, this way had a limitation; Fe-55, Nb-94 were precipitated as fluoride compounds as well as Ca. In this study, we have focused on developing a separation procedure stage by stage in the radioactive wastes with Sr-90, Fe-55, Nb-94, Ni-59,63 and large amount of Ca (1500 mg). The detailed steps are described below; (1) Separation of Fe-55, Nb-94, Ni-59,63 as metal hydroxide precipitates: low solubility product constant (Ksp) between pH 6 and pH 10. (2) Selective elimination of Ca-oxalate complex under strong acidic conditions. Consequently, all the metal sources were sequentially separated and quantitatively recovered by inductively coupled plasma atomic emission spectrometric (ICP-AES) analysis, the recovery is as follows; Sr-90 (3 mg): 89.47±5.48%, Fe-55 (20 mg): 99.80±3.19%, Nb-94 (20 mg): 97.45±2.42%, Ni-59,63 (2 mg): 83.59±15.31%, Ca (1500 mg): 85.32±6.38%, respectively. This methodology will help us separation of radioactive wastes efficiently if apply properly. (authors)

07 ISOTOPE AND RADIATION SOURCES↗
DOE OSTI2020

Heavy ion beam physics at Facility for Rare Isotope Beams

The Facility for Rare Isotope Beams (FRIB) will be the world's premier rare-isotope beam facility. Experiments with the majority (~80%) of the isotope predicted to exist will become available. The FRIB facility is based on a superconducting (SC) heavy ion linac with output energy above 200 MeV/u for any ions at beam power of 400 kW. FRIB includes a target facility for in-flight production of rare isotopes. A three-stage fragment separator will be used to prepare fast rare isotope beams with high-purity for nuclear physics experiments. The installation work of the accelerator and experimental systems is approaching completion and multi-stage beam commissioning activities started in summer 2017 with expected project completion in early 2022. In conclusion, the commencement of operation for users' experiments is planned immediately following the project completion.

43 PARTICLE ACCELERATORS↗
DOE OSTI2023

Twin-pulse seeding enables pump-probe capabilities in the EUV to soft X-ray spectrum at synchrotron light sources

Having previously reported that separating the two stages of echo-enabled harmonic generation (EEHG) with one or more bending magnet (BM) sections allows the BMs to serve as the desired source of momentum compaction, here we demonstrate that this arrangement can greatly reduce the total energy modulation required by any 4th generation synchrotron light source, leading to higher repetition rates as well as stronger coherent radiation output power, with significant benefits. Since the EEHG beamline performance is mainly determined by the momentum compaction, beam emittances and beta functions of a storage ring lattice, allowing for different separations between the two stages is a straightforward way to increase the momentum compaction of chicane 1. This also enables pump-probe capabilities in a novel context, where twin-pulse seeding on the same electron bunch would allow two distinct radiation pulses with an adjustable delay in the range of 0.1 to 10 ps. In the twin-pulse seeding scheme, the same electron bunch could undergo modulation from two distinct laser pulses. Later stages would produce independent harmonics in subsequent straight sections. There are two variations of this twin-pulse seeding scheme, supporting different scientific applications. With a common modulation in stage 1, the first option allows simultaneously two independent radiation sources, with a full coverage of the EUV (2.5 to 50 nm) to soft X-ray (1.25 to 2.5 nm) spectrum; for the second option, the same stage 2 undulator could generate two coherent pulses both fitting within the FEL bandwidth, or at distinct harmonics. We present particle tracking simulation studies based on the APS-U lattice, including quantum excitation and radiation damping. These simulations indicate that there is no degradation of the modulated longitudinal phase space even when the two stages are separated by as many as 10 BM sections.

36 MATERIALS SCIENCE↗
DOE OSTI2014

Thermodynamic analysis of cascade microcryocoolers with low pressure ratios

The vapor-compression cycle for refrigeration near ambient temperature achieves high efficiency because the isenthalpic expansion of the condensed liquid is a rather efficient process. However, temperatures are limited to about 200 K with a single-stage system. Temperatures down to 77 K are possible with many stages. In the case of microcryocoolers using microcompressors, pressure ratios are usually limited to about 6 or less. As a result, even more stages are required to reach 77 K. If the microcompressors can be fabricated with low-cost wafer-level techniques, then the use of many stages with separate compressors may become a viable option for achieving temperatures of 77 K with high efficiency. We analyze the ideal thermodynamic efficiency of a cascade Joule-Thomson system for various temperatures down to 77 K and with low pressure ratios. About nine stages are required for 77 K, but fewer stages are also analyzed for operation at higher temperatures. For 77 K, an ideal second-law efficiency of 83 % of Carnot is possible with perfect recuperative heat exchangers and 65 % of Carnot is possible with no recuperative heat exchangers. The results are compared with calculated efficiencies in mixed-refrigerant cryocoolers over the range of 77 K to 200 K. Refrigeration at intermediate temperatures is also available. The use of single-component fluids in each of the stages is expected to eliminate the problem of pulsating flow and temperature oscillations experienced in microcryocoolers using mixed refrigerants.

71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗
NASA NTRS1993

The initial flight anomalies of Skylab 1

At approximately 63 seconds into the flight of Skylab 1 on May 14, 1973, an anomaly occurred which resulted in the complete loss of the meteoroid shield around the orbital workshop. This was followed by the loss of one of the two solar array systems on the workshop and a failure of the inter stage adapter to separate from the S-II stage of the Saturn V launch vehicle. The investigation reported herein identified the most probable cause of this flight anomaly to be the breakup and loss of the meteoroid shield due to aerodynamic loads that were not accounted for in its design. The breakup of the meteoroid shield, in turn, broke the tie downs that secured one of the solar array systems to the workshop. Complete loss of this solar array system occurred at 593 seconds when the exhaust plume of the S-II stage retro-rockets impacted the partially deployed solar array system. Falling debris from the meteoroid shield also damaged the S-II inter stage adapter ordnance system in such a manner as to preclude separation. Of several possible failure modes of the meteoroid shield that were identified, the most probable in this particular flight was internal pressurization of its auxiliary tunnel which acted to force the forward end of the meteoroid shield away from the shell of the workshop and into the supersonic air stream. The pressurization of the auxiliary tunnel was due to the existence of several openings in the aft region of the tunnel. Another possible failure mode was the separation of the leading edge of the meteoroid shield from the shell of the workshop (particularly in the region of the folded ordnance panel) of sufficient extent to admit ram air pressures under the shield.

Source record↗
DOE OSTI2019

Recovery of Rare Earth Elements from Coal Mining Waste Materials

The objective of this proposed project was to locate coal overburden material that had rare earth elements (REEs) at concentrations of 300 ppm or higher. After securing the feedstock the next goal was to efficiently extract and purify the feedstocks to a purity of greater than 95%. A techno economic analysis was conducted to determine the economic viability of mining and processing REEs associated with Appalachian coal deposits. All aspects of mining, mineral processing, by-product potential, waste management, permitting and economics were examined. Attention was paid to the separation, degree of purification and marketing of Rare Earth elements. Along with REEs we evaluated the economics of the recovery of other metals of interest aong with the REEs. Our site location chosen was at the Jeddo Coal Site near Hazleton, Pennsylvania. The primary site was at the Upper Leigh High Mine. However, that changed to the North Eckley Mine site. We have analyzed a third site that will now be our second alternative to North Eckley. That site is the Highland mine site. This site is in a similar basin as the North Eckley site. During this project we evaluated various acids and extraction conditions. We have settled on using HCl as the acid of choice. One of the advantages of using HCl is it allows for easy removal of the highest contaminating metal, iron. When iron reacts with HCl in the presence of high chlorides it creates the anion complex FeCl 4 -1 . This FeCl 4 -1 complex will bind with an anion exchange resin. Greater than 99.8% of the iron is removed with this technique. Once the FeCl 4 -1 complex is bound to the anion exchange resin it can be released easily by just passing water over it. This water dilutes the FeCl 4 -1 to form FeCl 3 which is not anionic and therefore not attracted to the anion exchange resin. The FeCl 3 solution is a popular water flocculating agent used all over the world for water purification. We plan on this being one of our products produced. One of our goals was to create a multipurpose facility that was capable of handling multiple feedstocks. The proposed multipurpose facility will be able process all coal biproducts and coal products. These include 1.) clays that can easily be leached with ion exchange or acid 2.) Hard mineral deposits that can be leached with high pressure acid digestion 3.) Fly ash can be leached in the high-pressure acid digestion reactor. Fly ash is not a focus of this proposal but, the beneficial aspect of its utilization in this design cannot be overlooked. 4.) Acid Mine Drainage (AMD) Sludge is a high source of REE’s and can easily be dissolved to form a pregnant leach solution. Not shown on this simplified block flow diagram but crucial to its success is the recycle of acids. Our REE separation system is a continuous ion exchange process. The first stage is the separation of the non-REEs from the REEs. This is accomplished because the REEs are relatively larger than most of the non-REEs and typically have higher oxidation states (+3) than the non-REEs. In this step all the elements stick onto the column. However, as the columns are rinsed with various concentrations of acids different elements come off. For example, monovalent elements such as sodium and potassium elute off the column with a 1M HCl solution. Divalent elements such as calcium and magnesium do not elute until a 2M HCl solution is passed over the columns. The trivalent elements (REEs) are not eluted until a much higher concentrated acid is passed of the columns. Iron is also a trivalent, but it was removed in a prior anion exchange system. Aluminum is trivalent too, but it is much smaller than the REE atoms and elutes near the end of the 2 M HCl with the divalents. At the stage 2 and 3 our volume and masses have become too small to run on the continuous system. Therefore, we used a batch chromatography column or a flash chromatography column. The stage 2 process separates these REEs into 3 different fractions. A light, mid and heavy fraction. We calculated that we recovered greater than 90% of the REEs. This third column was packed with a different stationary phase. Five elements were chosen and purified to higher than 95% purity as shown by our internal testing. These elements were shipped to the DOE.

01 COAL, LIGNITE, AND PEAT↗
DOE OSTI2024

Microchannel reactive distillation for the conversion of aqueous ethanol to ethylene

Here we demonstrate the proof-of-concept for microchannel reactive distillation for alcohol-to-jet application: combining ethanol/water separation and ethanol dehydration in one unit operation. Ethanol is first distilled into the vapor phase, converted to ethylene and water, and then the water co-product is condensed to shift the reaction equilibrium. Process intensification is achieved through rapid mass transfer—ethanol stripping from thin wicks using novel microchannel architectures—leading to lower residence time and improved separation efficiency. Energy savings are realized with integration of unit operations. For example, heat of condensing water can offset vaporizing ethanol. Furthermore, the dehydration reaction equilibrium shifts towards completion by immediate removal of the water byproduct upon formation while maintaining aqueous feedstock in the condensed phase. For aqueous ethanol feedstock (40% w ), 71% ethanol conversion with 91% selectivity to ethylene was demonstrated at 220 °C, 600 psig, and 0.28 h -1 wt hour space velocity. 2.7 stages of separation were also demonstrated, under these conditions, using a device length of 8.3 cm. This provides a height equivalent of a theoretical plate (HETP), a measure of separation efficiency, of ~3.3 cm. By comparison, conventional distillation packing provides an HETP of ~30 cm. Thus, 9.1× reduction in HETP was demonstrated over conventional technology, providing a means for significant energy savings and an example of process intensification. Finally, preliminary process economic analysis indicates that by using microchannel reactive distillation technology, the operating and capital costs for the ethanol separation and dehydration portion of an envisioned alcohol-to-jet process could be reduced by at least 35% and 55%, respectively, relative to the incumbent technology, provided future improvements to microchannel reactive distillation design and operability are made.

10 SYNTHETIC FUELS↗
DOE OSTI2023

Techno-economic analysis of carbon dioxide capture from low concentration sources using membranes

Rising carbon dioxide (CO 2 ) levels in the atmosphere lead to global warming, causing climate change. As such, carbon capture has become necessary to slow the increase and reduce CO 2 levels in the atmosphere. Point source emissions have a wide range of CO 2 concentrations, but emissions below 3% CO 2 have mostly been ignored because Carbon capture from these sources has been viewed as costly and economically unsustainable. Membrane technologies are considered the most viable solution by virtue of more energy-efficient operation. Our group at Idaho National Laboratory (INL) has developed poly[bis((2-methoxyethoxy)ethoxy)phosphazene] (MEEP)-based carbon dioxide selective membranes with CO 2 /N 2 selectivity greater than 40 and CO 2 permeability greater than 450 Barrer. To understand the economics of carbon capture, a spreadsheet-based techno-economic analysis (TEA) model was developed to consider multiple parameters, including selectivity and permeability of the membranes, performance conditions such as the number of stages, module material, electricity price, membrane price, and capital financing. The cost of carbon capture in US $\$$/metric ton was calculated at various purities and compared with other membrane processes, cryogenic capture, solvent-based capture, and pressure swing adsorption-based capture. It was determined that a MEEP-based three-stage process had a capture cost of US $\$$ 50.1/metric ton for 99.8% purity CO 2 from a 1% CO 2 feed source in nitrogen (N 2 ). In conclusion, the capture cost using the best performing Pebax-based membrane was 464% higher, cryogenic capture was 60%–140% higher, pressure swing adsorption was 55%–165% higher, and chemical absorption was -10%–110% higher than MEEP-based membrane capture, respectively.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗