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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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501 records · Page 23

Global Characterization of Polygonally Fractured Terrain on Venus and Implications for a Climate Change Origin

On Earth, polygonal fractures with spacings of 1-100 cm form in lava flows that cool slowly under isotropic stress conditions. On Venus, polygonal fractures are observed with typical fracture spacings of 1-2 km, covering regions 10s to 100s of km across. These features have been proposed to form via cooling of lava flows or above subsurface intrusions, or due to surface cooling caused by climate change. A watershed algorithm was modified to search the entire Magellan image database autonomously for terrains with polygonal fractures. Here we characterize the 204 polygon terrains found using this method (including over 170 newly identified regions) with respect to size, morphology, stratigraphy, and geologic setting. These results are used to examine different models of origin.

S. E. Smrekar

Three-Dimensional, Multi-Phase Unsteady Flow of Water Undergoing Multiple Flow Regimes (Free Surface, Droplet, and Fluid Film)

Upgrades to the Mobile Launcher Rainbird nozzles were implemented for the Artemis II launch to increase water flow rates and improve the mobile launcher deck water coverage while minimizing the water throw distance to avoid impacting the Space Launch System (SLS) rocket nozzles. This analysis describes the use of a three-dimensional, multi-phase, free surface transient computational fluid dynamics (CFD) model to simulate the water flowing out through the Rainbird nozzle and ensure compliance with current Artemis requirements. Flow rates, pressures, velocities, nozzle throw distances and coverage areas were analyzed to ensure that system requirements are met. The completed results were used to make necessary modifications to the Ignition Overpressure Protection and Sound Suppression (IOP/SS) system Rainbird design by reshaping the nozzle used in the system.

CFD

STABLE Study for the Habitable Worlds Observatory

We report on progress on the STABLE study, which was awarded on the NASA 2023 ROSES D.19 opportunity. In the study, we are developing technologies for the Habitable Worlds Observatory (HWO) in four areas: Micrometeoroid Impact Mitigation, Telescope Temperature Control, Ultra-Stable Telescope Structure Materials and Modeling, and Improvement of Thermal Expansion Test Capability. This study is a collaboration between Northrop Grumman, Kratos, NeXolve, JPL, STScI, NASA’s White Sands Test Facility, and NASA Goddard’s Ultra-Stable Test Facility. We will also discuss our plans for our follow-on study as part of NASA’s 2024 ROSES D.19. In this study, we will address additional technologies as well as perform analysis of HWO architecture options.

Habitable Worlds Observatory

Simplified Aid for Extra-Vehicular Activity Rescue (SAFER) Battery Assessment

In 2013, the Boeing Company model 787-8 Dreamliner commercial aircraft experienced three catastrophic lithium (Li) battery failures. The cause of each failure resulted in a single-cell thermal runaway (TR) condition, which propagated to adjacent battery cells. Two of the failures involved rechargeable lithium-ion (Li-Ion) batteries, and the third event involved a nonrechargeable lithium-manganese dioxide (Li-MnO2) battery. In response to these Li battery failures, the NASA Engineering and Safety Center (NESC) approved a technical assessment of the International Space Station Simplified Aid for Extra-Vehicular Activity Rescue (SAFER) Li non-rechargeable battery. This assessment was conducted to evaluate the SAFER Li nonrechargeable battery safety design features against Boeing 787 Dreamliner Li battery failure lessons learned. Specifically, this investigation focused on assessing the severity of a SAFER battery TR hazard conditions.

Iannello, Christopher J.

Ejecta Management in a Safe Lithium Ion Battery Design

As lithium-ion battery energy densities continue to rise, managing the heat and pressure generated during failure events has become increasingly critical. Safety systems must effectively relieve pressure without releasing sparks, flames, or particulate matter, requiring robust filtration solutions. The challenge is compounded by the reduced free volume available for gas expansion in high-density designs, which increases the demands on these filters. While significant progress has been made through experimental studies and modeling efforts to understand the behavior of ejecta during battery failures, there remains a pressing need for practical, rule-of-thumb sizing parameters. These parameters would help correlate high-energy waste streams with appropriate filter design, ensuring reliable containment and safety. This talk will explore recent experimental findings in this area and discuss the potential pathways for developing these essential sizing guidelines.

Ejecta Management

Development of a Thermal Radiator Optimization Tool with Alternate Coolants

The development of a modeling tool to optimize the design of a thermal radiator based on capacity, rejection temperature, geometry, type and coolant is presented. The radiator size is determined from the desired capacity, environmental conditions and rejection temperature. Flow through the radiator is derived from the overall heat load and prescribed inlet to outlet delta temperature for a given coolant. The tool considers radiator geometry (i.e., tube spacing and diameter, face-sheet thickness, overall size, etc.) and general type (i.e., parallel/manifold versus serpentine) in the optimization. Selection from a handful of potential coolants is also available in the tool which primarily affects necessary tube diameter to maintain turbulent flow and minimize pressure drop. An Equivalent System Mass (ESM) approach is utilized to include pump power in the optimization. Results from the tool and potential future enhancements are also discussed.

Coolant

Development of a One-Domain Volume-Averaged Navier–Stokes Solver

The interaction between a high-enthalpy flow and a thermal protection material is inherently multiscale and multiphysics. In conventional aerothermal analyses, the external flow and material response are generally modeled using separate computational domains coupled through boundary conditions at the material surface. Although this approach has supported many practical applications, it requires assumptions about the location and behavior of the interface and may become difficult to apply when material decomposition, internal reactions, and surface recession substantially alter the porous structure. This report presents the development of a one-domain formulation in which the free-fluid and porous-material regions are represented within a single computational domain. The formulation is based on the volume-averaged Navier–Stokes (VANS) equations, derived from the governing equations for reacting, compressible flow and condensed material. Volume averaging transfers the influence of the unresolved material microstructure to the macroscale equations through effective transport properties, interfacial source terms, and dispersion fluxes. Particular attention is given to regions in which porosity and permeability vary rapidly, including the diffuse transition between a porous material and the surrounding fluid. The resulting equations are implemented in the Porous-material Analysis Toolbox based on OpenFOAM (PATO). The report describes the pressure–velocity coupling strategy used by the solver, examines spatial filtering techniques for deriving effective properties, and evaluates the influence of a smoothly varying interface permeability. Numerical demonstrations include canonical porous-flow configurations, a flow-tube configuration representative of FiberForm® permeability experiments, and the oxidation of a porous carbon material. The purpose of this work is to establish a mathematical and computational foundation for a unified treatment of flow and thermal protection material response. The present formulation is intended to support the progressive inclusion of additional physical processes, including multicomponent transport, finite-rate gas–surface chemistry, pyrolysis, internal oxidation, and material recession. It also provides a framework for connecting pore-scale simulations and microstructural characterization with macroscale aerothermal-response calculations. This report is intended for researchers and engineers working in computational fluid dynamics, porous-media transport, material response, and thermal protection system modeling. It documents both the theoretical development and the initial numerical assessment of the one-domain approach, while identifying the closure of effective and dispersion terms as an important subject for continued investigation.

Ablation

PC4CAST: A Tool for DSN Load Forecasting and Capacity Planning

Effectively planning the use and evolution of the Deep Space Network (DSN) is a complex problem involving many parameters. The tool that models many of these complexities, yet requires simple structured inputs and provides concise easy-to-understand metrics to aid in the planning process is discussed. The tool, PC4CAST, is used for both load forecasting (predicting how well planned that DSN resources meet expected demand) and as a decision support tool in the capacity-planning process (determining the relative benefits of capacity expansion options). It is now in use in the TDA Planning Office, has been used in numerous studies, and is also being used by the JPL Multimission Operations System Office (MOSO) as an integral part of Resource Allocation Team activities. Experience using the tool has helped to identify additional requirements that will further improve the planning process, which can be met by future PC4CAST versions.

S J Loyola

NASA Weather Balloon Demonstration of an Additively Manufactured Antenna

Additive manufacturing (AM) enables low-cost, lightweight, and geometrically flexible antennas for rapid deployment missions. This work reports a left-hand circularly polarized magneto-electric dipole printed on a Radix dielectric with inkjet silver metallization and demonstrated as a process replacement for NASA weather-balloon RF hardware. By combining substrate fabrication and metallization, AM provides value for unrecoverable or field-replaceable systems. A physics based verification workflow links AM-specific material behavior to electromagnetic performance and yields bounded total, radiation, and mismatch efficiencies. Standard surface-impedance and roughness models failed to reproduce the frequency-dependent radiation loss observed in printed inks, underscoring the need for AM-specific conductor parameterization. Mission testing confirmed TDRSS link closure from NASA’s Columbia Scientific Balloon Facility and validated a repeatable print–measure–fly workflow for bounding RF performance and qualifying AM antennas for field use.

Peter Moschetti

NASA Weather Balloon Demonstration of an Additively Manufactured Antenna

Additive manufacturing (AM) enables low-cost, lightweight, and geometrically flexible antennas for rapid deployment missions. This work reports a left-hand circularly polarized magneto-electric dipole printed on a Radix dielectric with inkjet silver metallization and demonstrated as a process replacement for NASA weather-balloon RF hardware. By combining substrate fabrication and metallization, AM provides value for unrecoverable or field-replaceable systems. A physics based verification workflow links AM-specific material behavior to electromagnetic performance and yields bounded total, radiation, and mismatch efficiencies. Standard surface-impedance and roughness models failed to reproduce the frequency-dependent radiation loss observed in printed inks, underscoring the need for AM-specific conductor parameterization. Mission testing confirmed TDRSS link closure from NASA’s Columbia Scientific Balloon Facility and validated a repeatable print–measure–fly workflow for bounding RF performance and qualifying AM antennas for field use.

Peter Moschetti

Experimental and analytical ion thruster research

The results of further spectroscopic studies on the plume from a 3 cm ion source operated on an argon propellant is reported on. In particular, it is shown that it should be possible to use the spectroscopic technique to measure the plasma density of the ion plume close to the grids, where it is difficult to use electrical probe measurements. How the technique, along with electrical probe measurements in the far downstream region of the plume, can be used to characterize the operation of a three-grid, 15 cm diameter thruster from NASA JPL is outlined. Pumping speed measurements on the Vacuum Research Facility have shown that this facility should be adequate for testing the JPL thruster at pressures in the low 10(exp -5) Torr range. Finally, we describe a simple analytical model which can be used to calculate the grid impingement current which results from charge-exchange collisions in the ion plume.

Wilhelmus M. Ruyten

Analysis of Screen Channel LAD Bubble Point Tests in Liquid Methane at Elevated Temperature

This paper examines the effect of varying the liquid temperature and pressure on the bubble point pressure for screen channel Liquid Acquisition Devices in cryogenic liquid methane using gaseous helium across a wide range of elevated pressures and temperatures. Testing of a 325 x 2300 Dutch Twill screen sample was conducted in the Cryogenic Components Lab 7 facility at the NASA Glenn Research Center in Cleveland, Ohio. Test conditions ranged from 105 to 160K and 0.0965 – 1.78 MPa. Bubble point is shown to be a strong function of the liquid temperature and a weak function of the amount of subcooling at the LAD screen. The model predicts well for saturated liquid but under predicts the subcooled data.

Reaction Control System

Motor Configuration Selection for A New Technical Challenge to Develop A 5 MW Cryogenic Motor and Drive

Due to aviation’s appreciable and growing share of humanity’s impact on our environment and estimates that CO2emissions only account for 34% of aviation’s total effective radiative forcing [1], there is a need to reach beyond climate goals that focus only on CO2emissions, such as the US Aviation Climate Action Plan’s [3] goal to reach net-zero carbon emissions by 2050.There is motivation to develop technology that pushes toward future large transport aircraft with net zero climate impact that are highly electrified (i.e., have higher power electrical propulsion system components). This paper describes a new, 6-year technical challenge to address this need by developing a 5 MW superconducting motor and cryogenic drive. Section 1 will detail the motivation for this work. Section 2 will describe the technical challenge and the selected specifications for the motor. Section 3 will present the results of a motor configuration trade study and the down selection of one configuration to develop a detailed design for. The technical challenge focuses on the design of a5 MW superconducting motor and cryogenic drive and demonstration of it at a 2+ MW scale to achieve TRL 3. Both fully superconducting (superconducting stator and rotor) and fully cryogenic (superconducting rotor and cryogenic stator) machine configurations will be explored. An emphasis will be placed on addressing the key tall poles for high power superconducting machines. Further details will be included in the full paper. The requirements and goals of the motor will be detailed. The rated speed (2,000 to 3,000 rpm) is defined to be appropriate for directly driving multi-MW fans or propellers. A range of rated speed is permitted because the motor is not designed for a specific aircraft and to provide design flexibility if AC losses in the stator winding are found to be a significant constraint (i.e., a lower speed can be selected to reduce electrical frequency). Relatively conservative requirements for efficiency (99%) and specific power (20 kW/kg) are defined, because TRL advancement and pushing toward flight readiness is emphasized over performance optimization. However, more aggressive efficiency and specific power goals are specified (99.9% and 40 kW/kg). The 3rd section will present the results of a motor configuration trade study. The study started with a qualitative assessment of sixteen motor configurations based on geometric, mechanical, thermal, and electromagnetic criteria. This assessment has been completed with three evaluators scoring all nine criteria. A configuration down select was made by prioritizing the sixteen configurations into four tiers based on each configuration’s total score and consideration of manufacturability, complexity, and support hardware (e.g., rotary vacuum seals, bearings). Configurations in priority A and B will be further evaluated through quantitative assessments, whereas those in priority C will only be further evaluated if time permits and priority D will not be further evaluated. Eight of the sixteen configurations were down selected for quantitative assessment, which will include analytical calculations and low-to moderate-fidelity finite element analysis to produce a preliminary Pareto front of efficiency versus specific power for each configuration. This assessment emphasizes the calculation of AC losses in the stator winding and an exploration of thermal management approaches to remove that heat and maintain cryogenic temperature. The final paper will include a description of each motor configuration that was considered. The quantitative assessments are underway, and an assessment of one configuration is complete for multiple stator conductor options. The remaining assessments are scheduled to be completed by late March so that the final down select to one configuration can be included in this paper.

Net Zero

Autonomous Detection and Classification of Lunar Minerals Using a Convolutional Neural Network Based Framework for the SUCR DALI Project

NASA’s long-term goal is to deploy humans to the Moon and, from there, advance human exploration to Mars, with Artemis missions as pivotal milestones. Raman spectroscopy can uniquely identify minerals, compounds, water states, and other materials, providing distinctive fingerprints for classification. A Raman instrument has been successfully deployed and utilized on the Mars surface via the Perseverance rover, but has not yet been utilized at the lunar surface The SUCR DALI project is working towards developing a Raman spectroscopy instrument to be applied in various lunar mission concepts, including within the Artemis program. The objective of my research is to assist in the maturation of the proposed SUCR DALI lunar Raman instrument through the development of an autonomous detection and classification model capable of identifying minerals and water states on the Moon’s surface.

Convolutional Neural Networks

Metallurgical and Thermal Properties of 57Ni-40Ti-3Hf (wt%)

Selected properties of 57Ni-40Ti-3Hf (wt%) were measured to further develop this material for use in aerospace rolling-element bearings. The average grain size and microindentation hardness of the material at room temperature were 90 μm and 549 HV, respectively. From room temperature to 500 °C, electrical resistivity increased from 8.9×10–7 to 11.3×10–7 Ω⋅m, thermal expansion coefficients varied from 1.1×10–5 to 1.2×10–5 mm/mm⋅°C, specific heat increased from 0.44 to 0.53 W⋅sec/g⋅K, thermal diffusivity rose from approximately 0.003 to 0.005 cm2/sec and thermal conductivity increased from approximately 0.09 to 0.19 W/cm⋅K. The behavior of the material can be explained by well-known metallurgical theory. These results are expected to provide a basis for design and modeling of future aerospace components.

rule of mixtures

Workshop on Advances in NASA-Relevant, Minimally Invasive Instrumentation

The purpose of this meeting is to highlight those advances in instrumentation and methodology that can be applied to the medical problems that will be encountered as the duration of manned space missions is extended. Information on work that is presently being done by NASA as well as other approaches in which NASA is not participating will be exchanged. The NASA-sponsored efforts that will be discussed are part of the overall Space Medicine Program that has been undertaken by NASA to address the medical problems of manned spaceflight. These problems include those that have been observed in the past as well as those which are anticipated as missions become longer, traverse different orbits, or are in any way different. This conference is arranged in order to address the types of instrumentation that might be used in several major medical problem areas. Instrumentation that will help in the cardiovascular, musculoskeletal, and psychological areas, among others will be presented. Interest lies in identifying instrumentation which will help in learning more about ourselves through experiments performed directly on humans. Great emphasis is placed on non-invasive approaches, although every substantial program basic to animal research will be needed in the foreseeable future. Space Medicine is a rather small affair in what is primarily an engineering organization. Space Medicine is conducted throughout NASA by a very small skeleton staff at the headquarters office in Washington and by our various field centers. These centers include the Johnson Space Center in Houston, Texas, the Ames Research Center in Moffett Field, California, the Jet Propulsion Laboratory in Pasadena, California, the Kennedy Space Center in Florida, and the Langley Research Center in Hampton, Virginia. Throughout these various centers, work is conducted in-house by NASA's own staff scientists, physicians, and engineers. In addition, various universities, industries, and other government laboratories perform research that cannot be effectively carried out in-house. At the moment, approximately 50% of the work is performed in-house and 50% is extramural. The area of bioinstrumentation pervades every one of our problem areas. In each, equipment or procedures are being developed that will allow more clinical work to be done in a ground-based or spacecraft setting. Although work of this kind goes on throughout the NASA organization and through its grants and contracts in the community at large, the major thrust of it is concentrated at the Jet Propulsion Laboratory which plays a lead role in this type of research and acts as the lead center in bioinstrumentation for NASA. It is recognized that there is much additional research being pursued in this area which would be potentially valuable to NASA and could, with some stimulation from, be made more applicable to NASA's needs. It is hoped, therefore, that the proceedings of this conference will be used as the basis for developing research strategies to be used as a road map to point the way in which NASA's own sponsored program should proceed over the course of the next three years. Additionally, it is hoped that the conference will highlight additional areas in which NASA should be involved either in-house or through the sponsorship of non-NASA scientists. NASA would also like to get an idea of which areas should be emphasized or perhaps de-emphasized among those that it is currently pursuing. In considering these questions, the discussion should concern itself not so much with whether a particular procedure or piece of equipment would work in a spacecraft, but rather, with whether the procedures that are advocated are at the state-of-the-art or beyond the state-of-the-art and whether they hold promise of giving additional insight into the problems to be confronted as humans venture into space for longer and longer periods of time.

Source record

Harness Thermal Heat Loss Measurement for a Lunar Surface-Deployed LEMS Artemis III Payload

The Lunar Environment Monitoring Station (LEMS) is an autonomous, survive-the-lunar-night seismic suite to be deployed on the Lunar surface by the Artemis III crew and designed to operate continuously for two years. It will see the extremes of the Lunar south pole thermal environment where surface temperatures range from -200°C to +20°C and where nighttime duration is at least 354 hours. Given power and mass constraints, the thermal system is limited to 2.5 Watts of heat during the lunar night. The electrical harnessing named the Signal and Power Passthrough (SAPP) was designed to minimize heat loss while meeting power and signal integrity requirements. To mitigate risk due to uncertainty associated with the harnessing materials, routing, and tie-downs, a flight-like thermal conductance test was performed to measure the heat loss. The test methodology, results, and model correlation are presented.

TVAC

Harness Thermal Heat Loss Measurement for A Lunar Surface-Deployed LEMS Artemis III Payload

The Lunar Environment Monitoring Station (LEMS) is an autonomous, survive-the-lunar-night seismic suite to be deployed on the Lunar surface by the Artemis III crew and designed to operate continuously for two years. It will see the extremes of the Lunar south pole thermal environment where surface temperatures range from -200°C to +20°C and where nighttime duration is at least 354 hours. Given power and mass constraints, the thermal system is limited to 2.5 Watts of heat during the lunar night. The electrical harnessing named the Signal and Power Passthrough (SAPP) was designed to minimize heat loss while meeting power and signal integrity requirements. To mitigate risk due to uncertainty associated with the harnessing materials, routing, and tie-downs, a flight-like thermal conductance test was performed to measure the heat loss. The test methodology, results, and model correlation are presented.

Thermal