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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 1,765 records · Page 98

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NASA NTRSDate not supplied

Aerothermal Shape Optimization of Actively-Cooled Battery Packs using Conjugate Heat Transfer

Thermal management for battery is important for electric aircraft because battery temperature is critically important to vehicle safety, and it also has direct impact on the efficiency of the battery system. Because ambient air is a readily available resource for aircraft, this paper considers an active cooling concept with forced convection of ambient air through the battery pack. Conjugate heat transfer analysis is used to solve the coupled aero-thermal problem, which consists of a finite-volume computational fluid dynamics solver for the fluid domain, and a conduction heat transfer solver for the solid domain. A mixed Neumann and Dirichlet boundary condition is developed for the fluid-solid interface, which allows the solid domain to completely submerge in the fluid domain. A gradient-based optimization method is adopted, and the discrete adjoint approach implemented in DAFoam is used to efficiently compute the gradients. The aero-thermal coupling for primal analysis and gradient computation is handled using the OpenMDAO-based MPhys framework. A constant heat source is prescribed for the battery cells, and the battery shape (design variable) is optimized to minimize cooling pump power and battery weight (composite objective function) while keeping the battery temperature below a threshold (constraint). The optimized design achieves a 44.6% and 1.5% reduction in the cooling pump power and battery weight, respectively, and the maximal temperature constraint is satisfied. This work has the potential to reduce battery-pack weight, improve performance, and reduce the weight of thermal management systems for electric vertical take-off and landing aircraft.

thermal management↗

NASA NTRSDate not supplied

Aerothermal Shape Optimization of Actively-Cooled Battery Packs Using Conjugate Heat Transfer

heat transfer↗

DOE OSTI2023

Solid State Detectors Dedicated to Fast Timing

Development and implementation of 4D-trackers will play a key role at future machines. These detectors will reduce backgrounds, improve track reconstruction and Level-1triggering, and enable new capabilities for particle identification and reconstruction of long-lived particles. All of these pose unique challenges and opportunities to detector design. In this talk I will overview the currently available technologies and areas of active R&D, and proposed disruptive technologies to achieve the goals for future experiments.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

DOE OSTI2024

Sliceable, Moldable, and Highly Conductive Electrolytes for All-Solid-State Batteries

All-solid-state batteries (ASSBs) require solid electrolytes with high ionic conductivity, stability, and deformability for optimal energy and power density. Here, we developed lithium-deficient lithium yttrium bromide (LYB) solid electrolytes, Li 3–x YBr 6–x (0 ≤ x ≤ 0.50), using a comelting method with controlled lithium deficiency. These electrolytes exhibit favorable mechanical properties such as high moldability and sliceability. The Li 2.65 YBr 5.65 composition has an ionic conductivity of 4.49 mS cm –1 at 25 °C and an activation energy of 0.28 eV. Compared to Li 3 YBr 6 , Li 2.65 YBr 5.65 demonstrates improved rate performance and cycling stability in ASSBs. High-resolution X-ray diffraction confirms the formation of the LYB phase with a C2/m space group. Structural analysis reveals increased cation disorder and larger polyhedral volumes for x > 0 in Li 3–x YBr 6–x , contributing to reduced Li + migration energy barriers. Bond valence site energy calculations and molecular dynamics simulations reveal enhanced 3D lithium-ion transport. NMR spectroscopy further highlights increased Li + dynamics and impurity elimination.

Poudel, Tej P. [Florida State Univ., Tallahassee, ↗

DOE OSTI2024

Narrow-bandwidth tunable optical filter stabilized by Newton’s rings fringe analysis

The resolution of grating spectrometers is insufficient to resolve many features present in the emission spectra of solid-state quantum emitters. Spectral resolution may be improved by inserting a Fabry–Perot interferometer (FPI) whose length is tuned by a piezoelectric actuator. Yet piezo creep and thermal fluctuations cause instability that makes this solution unsuitable for measurement times longer than tens of seconds. To overcome this challenge, we employ active feedback derived from the Newton’s rings interference pattern formed by the reflection of a single-frequency laser from the FPI cavity. The resulting FPI transmission frequency is stable to within 50 MHz over several hours.

KC, Raju Bhai (ORCID:0000000267406588)↗

DOE OSTI2024

Characterization Results for the October 2024 Tank Farm 3H Evaporator Overhead Sample

On an annual basis, Savannah River Mission Completion (SRMC) provides 2H and 3H evaporator overhead samples to Savannah River National Lab (SRNL) to be analyzed per Section 5.2 of the Effluent Treatment Project (ETP) Waste Compliance Plan (WCP) and the Waste Acceptance Criteria (WAC). This report presents characterization results for the October 2024 3H evaporator overhead sample. The sample was clear and colorless with no visible solids. The results provide measurements for cesium-137 (137Cs), strontium-90 (90Sr), and iodine-129 (129I) with the radionuclide concentration limits specified by the WAC. These analyses were performed in duplicate, and a summary of the analytical results for this 3H evaporator overhead sample includes the following: The measured cesium-137 activity in the 3H evaporator overhead sample averaged 6.72E+01 dpm/mL, (3.90E+00 %RSD), which is below the ETP WAC limit of 1.30E+03 dpm/mL. The strontium-90 activity in the 3H evaporator overhead sample averaged <2.72E+00 dpm/mL, which is below the ETP WAC limit of 1.76E+02 dpm/mL. The iodine-129 activity in the 3H evaporator overhead sample averaged <1.63E-01 dpm/mL, which is below the ETP WAC limit of 1.00E+00 dpm/mL.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

DOE OSTI2025

PFAS Waste Management for Industrial, Water, and Wastewater Treatment Facilities

Per- and polyfluoroalkyl substances (PFAS), including perfluorooctanesulfonic acid (PFOS) and perfluorooctanoic acid (PFOA), are widely used in industrial and consumer products due to their unique water and oil repelling properties. These slow-degrading and bio-accumulating compounds, often called "forever chemicals," are not typically removed by conventional industrial and municipal water/wastewater (W/WW) treatment. This tip of the month provides comprehensive strategies for managing PFAS-contaminated waste streams. Understanding the various types of PFAS waste streams is the first step in managing them. Primary PFAS waste includes contaminated process W/WW and solid materials directly from the production and processing of PFAS-containing materials. These might come from manufacturing facilities, firefighting training areas, or other industrial operations where PFAS compounds are used or were historically present. Secondary PFAS waste results from treatment and disposal mechanisms of primary PFAS waste streams, including spent activated carbon, used ion exchange resins, membrane reject streams, PFAS-laden backwash water, landfill leachate, incineration residuals, etc. TABLE 1 lists examples of the most common PFAS waste streams in different industrial facilities.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

NASA NTRS1973

Experiments on the origin of molecular chirality by parity non-conservation during beta-decay

Experiments are described to test a theory for the origin of optical activity wherein the longitudinally polarized electrons resulting from parity violation during radioactive beta decay, and their resulting circularly polarized Bremsstrahlung, might interact asymmetrically with organic matter to yield optically active products. Experiments involve subjecting a number of racemic and optically active amino acid samples to irradiation in a 61700 Ci90SR-90Y beta radiation source for a period of 1.34 years, then examining them for any asymmetric effects by means of optical rotatory dispersion and analytical gas chromatography. In the cases of D,L-leucine, norleucine, norvaline and proline as solids, of D,L-leucine in solution and of D,L-tyrosine in alkaline solution no optical rotation was observed during CRD measurements in the 250-630 nm spectral region. While slight differences were noted in the percent radiolysis of solid D- (12.7%) and L-leucine (16.2%) as determined by GC, no enrichment of either enantiomer was found.

Bonner, W. A.↗

NASA NTRS1978

Role of back stress in the creep behavior of particle strengthened alloys

Recent developments in the interpolation of high-temperature steady-state creep results have introduced the concept that the stress dependence of the creep rate should be in terms of the effective stress referred to as the applied stress minus a back stress. This paper reports on back stresses taken from data on a gamma-prime-strengthened wrought nickel-base superalloy, an oxide dispersion-strengthened ODS nickel-base solid solution alloy, and an ODS nickel-base superalloy. The effect of air versus vacuum environments and the effect of dynamic changes in the strengthening microstructures on the magnitude of the back stress are assessed. The role of modulus normalization and the back stress correction in determining the true creep activation energy are examined. It is shown that the high values of the apparent stress exponent 'n' of the steady-state creep equation can be easily explained through a relationship between n, the true stress exponent of steady-state creep, and the stress which when subtracted from the applied stress results in the effective driving stress acting on the mobile dislocations during creep.

Purushothaman, S.↗

NASA NTRS1980

Recovery of aluminum from composite propellants

Aluminum was recovered from solid rocket propellant containing a small amount of oxidizer by depolymerizing and dissolving propellant binders (containing functional or hydrolyzable groups in a solution of sodium methoxide) in an alcohol solvent optionally containing an aliphatic or aromatic hydrocarbon co-solvent. The solution was filtered to recover substantially all the aluminum in active form.

Shaw, G. C.↗

NASA NTRS1991

Conditions for accretion-induced collapse of white dwarfs

Recent discovery of an unexpectedly large number of low-mass binary pulsars (LMBPs) in globular clusters has instigated active discussions on the evolutionary origin of binary pulsars. Prompted by the possibility that at least some of LMBPs originate from accretion-induced collapse (AIC) of white dwarfs, a reexamination is conducted as to whether or not AIC occurs for the new models of O + Ne + Mg white dwarfs and solid C + O white dwarfs that can ignite explosive nuclear burning at significantly lower central densities than in the previous models. Even with low critical densities, AIC is still much more likely than explosion for both types of white dwarfs. Possible regions for AIC are presented in a diagram of mass accretion rate vs initial mass of the white dwarfs.

Nomoto, Ken'ichi↗

NASA NTRS1999

STS-103 Crew Activity Report/Flight Day 1 Highlights

Live footage of the astronauts sitting around the table with the traditional cake is presented. The crew of Discovery, Mission Commander Curtis L. Brown, Pilot Scott J. Kelly, Mission Specialists Steven L. Smith, C. Michael Foale, John M. Grunsfeld, Claude Nicollier, and Jean-Francois Clervoy are seen executing various activities including suit-up, walkout to the Astro-Van, and strap-in into the shuttle. Also presented are beautiful panoramic views of the shuttle on the pad. During this night launch, footage of the main engine start, ignition of the boosters, liftoff of Discovery, and separation of the solid rocket boosters are seen.

Source record↗

NASA NTRS2001

The Launch Systems Operations Cost Model

One of NASA's primary missions is to reduce the cost of access to space while simultaneously increasing safety. A key component, and one of the least understood, is the recurring operations and support cost for reusable launch systems. In order to predict these costs, NASA, under the leadership of the Independent Program Assessment Office (IPAO), has commissioned the development of a Launch Systems Operations Cost Model (LSOCM). LSOCM is a tool to predict the operations & support (O&S) cost of new and modified reusable (and partially reusable) launch systems. The requirements are to predict the non-recurring cost for the ground infrastructure and the recurring cost of maintaining that infrastructure, performing vehicle logistics, and performing the O&S actions to return the vehicle to flight. In addition, the model must estimate the time required to cycle the vehicle through all of the ground processing activities. The current version of LSOCM is an amalgamation of existing tools, leveraging our understanding of shuttle operations cost with a means of predicting how the maintenance burden will change as the vehicle becomes more aircraft like. The use of the Conceptual Operations Manpower Estimating Tool/Operations Cost Model (COMET/OCM) provides a solid point of departure based on shuttle and expendable launch vehicle (ELV) experience. The incorporation of the Reliability and Maintainability Analysis Tool (RMAT) as expressed by a set of response surface model equations gives a method for estimating how changing launch system characteristics affects cost and cycle time as compared to today's shuttle system. Plans are being made to improve the model. The development team will be spending the next few months devising a structured methodology that will enable verified and validated algorithms to give accurate cost estimates. To assist in this endeavor the LSOCM team is part of an Agency wide effort to combine resources with other cost and operations professionals to support models, databases, and operations assessments.

Prince, Frank A.↗

NASA NTRS2002

Hydrothermal Origin for Carbonate Globules in Martian Meteorite ALH84001: A Terrestrial Analogue from Spitsbergen (Norway)

Carbonate minerals in the ancient Martian meteorite ALH84001 are the only known solid phases that bear witness to the processing of volatile and biologically critical compounds (CO2, H2O) on early Mars. Similar carbonates have been found in xenoliths and their host basalts from Quaternary volcanic centers in northern Spitsbergen (Norway). These carbonates were deposited by hot (i.e., hydrothermal) waters associated with the volcanic activity. By analogy with the Spitsbergen carbonates, the ALH84001 carbonates were probably also deposited by hot water. Hydrothermal activity was probably common and widespread on Early Mars, which featured abundant basaltic rocks, water as ice or liquid, and heat from volcanos and asteroid impacts. On Earth, descendants of the earliest life forms still prefer hydrothermal environments, which are now shown to have been present on early Mars.

Treiman, Allan H.↗

NASA NTRS2003

Measurements of the Ice Water Content of Cirrus in the Tropics and Subtropics: Instrument Details and Validation - I

We describe an instrument mounted in a pallet on the NASA WB-57 aircraft that is designed to measure the sum of gas phase and solid phase water, or total water, in cirrus clouds. Using an isokinetic inlet, a 600-watt heater mounted directly in the flow, and Lyman-alpha photofragment fluorescence technique for detection, accurate measurements of total water have been made over almost three orders of magnitude. Isokinetic flow is achieved with an actively controlled roots pump by referencing aircraft pressure, temperature, and true air speed, together with instrument flow velocity, temperature, and pressure. During CRYSTAL FACE, the instrument operated at duct temperatures sufficiently warm to completely evaporate particles up to 150 microns diameter. In flight diagnostics, intercomparison with water measured by absorption in flight, as well as intercomparisons in clear air with water vapor measured by the Harvard water vapor instrument and the JPL infrared tunable diode laser hygrometer validate the detection sensitivity of the instrument and illustrate minimal hysteresis from instrument surfaces. The simultaneous measurement of total water and water vapor in cirrus clouds yields their ice water content.

Weinstock, E. M.↗

NASA NTRS1998

Polymerization on the rocks: theoretical introduction

It is difficult if not impossible to synthesize long polymers of amino acids, nucleotides, etc., in homogeneous aqueous solution. We suggest that long polymers were synthesized on the surface of minerals in a prebiotic process analogous to solid-phase synthesis. Provided that the affinity of a mineral for an oligomer increases with the length of the oligomer, adsorption must become essentially irreversible for sufficiently long oligomers. Irreversibly adsorbed oligomers may be elongated indefinitely by repeated cycles in which the mineral with its adsorbed oligomers is first incubated with activated monomers and then washed free of deactivated monomer and side-products. We discuss in some detail the formation of oligomers of negatively-charged amino acids such as glutamic acid on anion-exchange minerals such as hydroxylapatite or illite. We show that the average length of adsorbed oligomers at steady state, n, depends on the balance between the rate of chain elongation and the rate of hydrolysis, and we derive a very approximate formula for n.

NASA Discipline Exobiology↗

NASA NTRS2005

INSPACE CHEMICAL PROPULSION SYSTEMS AT NASA's MARSHALL SPACE FLIGHT CENTER: HERITAGE AND CAPABILITIES

NASA s Marshall Space Flight Center (MSFC) is well known for its contributions to large ascent propulsion systems such as the Saturn V rocket and the Space Shuttle external tank, solid rocket boosters, and main engines. This paper highlights a lesser known but very rich side of MSFC-its heritage in the development of in-space chemical propulsion systems and its current capabilities for spacecraft propulsion system development and chemical propulsion research. The historical narrative describes the flight development activities associated with upper stage main propulsion systems such as the Saturn S-IVB as well as orbital maneuvering and reaction control systems such as the S-IVB auxiliary propulsion system, the Skylab thruster attitude control system, and many more recent activities such as Chandra, the Demonstration of Automated Rendezvous Technology (DART), X-37, the X-38 de-orbit propulsion system, the Interim Control Module, the US Propulsion Module, and multiple technology development activities. This paper also highlights MSFC s advanced chemical propulsion research capabilities, including an overview of the center s Propulsion Systems Department and ongoing activities. The authors highlight near-term and long-term technology challenges to which MSFC research and system development competencies are relevant. This paper concludes by assessing the value of the full range of aforementioned activities, strengths, and capabilities in light of NASA s exploration missions.

McRight, P. S.↗

NASA NTRS2009

Lunar Base Life Support Failures

Dynamic simulation of the lunar outpost habitat life support was undertaken to investigate the impact of life support failures and to investigate responses. Some preparatory static analysis for the Lunar Outpost life support model, an earlier version of the model, and an investigation into the impact of Extravehicular Activity (EVA) were reported previously. (Jones, 2008-01-2184, 2008-01-2017) The earlier model was modified to include possible resupply delays, power failures, recycling system failures, and atmosphere and other material storage failures. Most failures impact the lunar outpost water balance and can be mitigated by reducing water usage. Food solids, nitrogen can be obtained only by resupply from Earth. The most time urgent failure is a lass of carbon dioxide removal capability. Life support failures might be survivable if effective operational solutions are provided in the system design.

Jones, Harry W.↗