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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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All sourcesNASA NTRSDOE OSTI
DOE OSTI2022

MEASUR - Manufacturing Energy Assessment Software for Utility Reduction

MEASUR your energy savings with the free DOE MEASUR software The Department of Energy (DOE), with Oak Ridge National Laboratory (ORNL), released version 1.0 of their energy efficiency software tool MEASUR (Manufacturing Energy Assessment Software for Utility Reduction). MEASUR has been available for several years as a beta version, being tested by industry experts and real users, and will continue to be updated and improved in the coming years. It is an integrated suite of tools to aid manufacturers in improving the efficiency of energy systems and equipment within a plant, including motors, pumps, fans, process heating, steam, and compressed air. Additionally, there are modules for wastewater energy analysis and to help perform energy treasure hunts. Several calculators are also included, allowing users to independently perform smaller calculations and analyses (such as estimating pump head, performing a fan traverse analysis, estimating waste heat recovery potential, and cataloging compressed air leaks). The MEASUR modules are based on previous DOE software tools that have been used by industry since the early 2000s (such as MotorMaster, AirMaster+, PSAT, PHAST, and FSAT). The original tools only ran on Windows operating systems, and by Windows 10, most of them were inoperable. DOE started their energy efficiency software tool revitalization effort in 2016, first with PSAT (for pumps), then began to integrate the other tools and expand their functionality and utility. The new MEASUR suite provides an extensively more user-friendly, modern, and versatile set of tools. All the assessment modules and most of the calculators have several visual components and graphs and detailed help text for every user input. To help reach international users, the tool utilizes Google translate and users can easily change unit systems, even converting existing user inputs if desired. The assessment files can be organized within the internal file system and easily shared to other users, regardless of their operating system. The entire suite is free, open-source, and can be downloaded on Windows, Mac, or Linux operating systems.

Accawi, Gina [Oak Ridge National Lab. (ORNL), Oak ↗
DOE OSTI2021

Demonstration of Electrochemically-Driven CO 2 Separation Using Hydroxide Exchange Membranes

Hydroxide exchange membrane fuel cells (HEMFCs) are a potentially lower-cost hydrogen fuel cell technology; however, ambient levels of CO 2 in air significantly reduce HEMFCs’ performance. In this work, we demonstrate an electrochemically-driven CO 2 separator (EDCS) which can be used to remove ambient levels of CO 2 from air upstream of the HEMFC stack in fuel cell vehicles, protecting it from CO 2 -related performance losses. The EDCS operating window was explored for current density, anode flow, and cathode flow with respect to its impact on CO 2 separation performance. Additionally, gas-phase mass transport was improved by selecting flow fields and gas diffusion layers conducive to the EDCS operating regime. The use of a carbon-ionomer interlayer at the cathode was explored and improved CO 2 removal performance from 77.7% to 98.2% at 20 mA cm −2 . An analytical, 1-D model is used to explain the experimental observations and design improvements. A single-cell, 25 cm 2 EDCS using the aforementioned improved design demonstrated greater than 98% CO 2 removal at a cathode flow rate of 1300 sccm for 100 h with 2.7% hydrogen stack consumption.

Matz, Stephanie↗
NASA NTRS1996

LTCP 2D Graphical User Interface. Application Description and User's Guide

A graphical user interface (GUI) written for NASA's LTCP (Liquid Thrust Chamber Performance) 2 dimensional computational fluid dynamic code is described. The GUI is written in C++ for a desktop personal computer running under a Microsoft Windows operating environment. Through the use of common and familiar dialog boxes, features, and tools, the user can easily and quickly create and modify input files for the LTCP code. In addition, old input files used with the LTCP code can be opened and modified using the GUI. The application is written in C++ for a desktop personal computer running under a Microsoft Windows operating environment. The program and its capabilities are presented, followed by a detailed description of each menu selection and the method of creating an input file for LTCP. A cross reference is included to help experienced users quickly find the variables which commonly need changes. Finally, the system requirements and installation instructions are provided.

Ball, Robert↗
DOE OSTI2022

Closo ‐Borate Gel Polymer Electrolyte with Remarkable Electrochemical Stability and a Wide Operating Temperature Window

Abstract A major challenge in the pursuit of higher‐energy‐density lithium batteries for carbon‐neutral‐mobility is electrolyte compatibility with a lithium metal electrode. This study demonstrates the robust and stable nature of a closo ‐borate based gel polymer electrolyte (GPE), which enables outstanding electrochemical stability and capacity retention upon extensive cycling. The GPE developed herein has an ionic conductivity of 7.3 × 10 −4 S cm −2 at room temperature and stability over a wide temperature range from −35 to 80 °C with a high lithium transference number ( = 0.51). Multinuclear nuclear magnetic resonance and Fourier transform infrared are used to understand the solvation environment and interaction between the GPE components. Density functional theory calculations are leveraged to gain additional insight into the coordination environment and support spectroscopic interpretations. The GPE is also established to be a suitable electrolyte for extended cycling with four different active electrode materials when paired with a lithium metal electrode. The GPE can also be incorporated into a flexible battery that is capable of being cut and still functional. The incorporation of a closo ‐borate into a gel polymer matrix represents a new direction for enhancing the electrochemical and physical properties of this class of materials.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
NASA NTRS1962

Orbital Launch Operations: Escape Window Analysis

The analysis of the gross aspects of the flight mechanics for lunar trajectories from orbital launch is presented. An attempt is made to define the launch requirements from an earth orbit, the geometrical relationships existing between an Orbital Launch Facility in earth orbit and the moon in its orbit, the departure trajectory sensitivity to energy and time requirements, the launch-on-time problem and the orbital "escape window".

ESCAPE↗
NASA NTRSDate not supplied

Computational Tools to Design Molten Salt Electrolytes for High-Temperature Environments

Current Li-ion batteries are designed for a small operating window of 5 °C to 55 °C. Modifications to the electrolyte for operation in Mars atmosphere extended this range on the lower bound to ~ -40 °C. These operating-temperature ranges are far from those presented in high-temperature environments, such as the Venus surface, where temperatures are around 450 °C. Protecting the state-of-the-art Li-ion batteries require insulations that decreases the volumetric capacity and limiting the operational time-window. These unique challenges require a paradigm shift in materials used for designing high-temperature batteries. Molten salt electrolyte-based batteries offer a plausible route to designing high-temperature batteries. ZEBRA batteries are known to be one of the safest energy storage devices operating at 270-350 °C. Nitrate based eutectics, operating at 150 °C have also been used in Li-O2 batteries. In this study, we will examine molten-salt electrolyte transport and electrochemical properties using first-principles computations and benchmark against experiments. Further, we will present thermodynamics-based models for designing and predicting melting point of molten salt mixtures. Based on these computational tools, new molten salt mixtures designed with desired operating temperatures and electrochemical windows will be presented. Implications of these new eutectics in the context of high-temperature environment exploration will also be discussed.

Balachandran Radhakrishnan↗
DOE OSTI2023

Multipacting analysis of the SNS drift tube linac (DTL) RF vacuum window using Spark3d

An ongoing study at the Spallation Neutron Source (SNS) seeks to better understand and address potential multipacting issues associated with the Drift Tube Linac (DTL) RF vacuum windows. An analysis of several failed operational windows showed indications of excessive RF heating on the TiN-coated alumina ceramics. Coupled with vacuum bursts and arcing during conditioning and/or operational periods, these problems have been attributed to electron activity likely caused by multipacting. The status of the study, 3-D electromagnetic simulation results, mitigating techniques and a future experimental plan for studying multipacting in the SNS DTL vacuum windows are presented.

Toby, George↗
DOE OSTI2023

Development of window scheduler algorithm exploiting natural ventilation and thermal mass for building energy simulation and smart home controls

Building energy simulations often rely on abstract assumptions when it comes to natural ventilation, such as ‘windows always open [or closed]’ or ‘windows open when outdoor temperature is below a certain threshold.’ However, simulations based on these assumptions fail to fully exploit the cooling potential of natural ventilation, as its effectiveness can be enhanced or diminished by various factors, including the presence of thermal mass. This issue also extends to smart home controls, where determining the window schedule becomes challenging without information about the building's response to outdoor conditions. To address these issues, this study has developed an analytical model for window operation schedules that leverages the passive cooling from natural ventilation. The analytical model was validated against a Modelica simulation. A case study utilizing the BESTEST model of ANSI/ASHRAE Standard 140 underwent validation with EnergyPlus simulations, showing strong concordance. The algorithm provides window schedule recommendations adapted to various airflow rates, thermal masses, and climate variations. Notably, the case study demonstrated that proper window scheduling could reduce indoor temperature by up to 8 °C under the given simulation settings, thereby improving resilience and indicating potential energy savings. Furthermore, the paper explores the potential opportunities and challenges this approach presents, especially for building simulation and smart home applications.

42 ENGINEERING↗
NASA NTRS1983

Designing for a new era of launch vehicle operational efficiency

It is pointed out that early recognition of operational requirements and assessment of their effects provides the best chance of designing an economically viable future space transportation system (FSTS). Operational factors which may influence configuration design include fleet size, operation mode, refurbishment, and the resource requirements. FTST has a simplified operational role compared to the Space Shuttle, which, in addition to transportation, must perform experiments, support payloads, and stay long on orbit. In the future a space station will perform many of these tasks. The FSTS comprises a two-stage fully reusable launch vehicle designed to carry 150,000 lb to a space station, off-load, and return. It would always be launched fully loaded, and its cargo would be processed and redistributed at the space station. Attention is given to ground servicing, flight operations, rendezvous-compatible orbits, launch windows, standard trajectories, entry windows, operational costs, the mission model, and resource requirements.

Talay, T. A.↗
NASA NTRS2005

Three-Dimensional Audio Client Library

The Three-Dimensional Audio Client Library (3DAudio library) is a group of software routines written to facilitate development of both stand-alone (audio only) and immersive virtual-reality application programs that utilize three-dimensional audio displays. The library is intended to enable the development of three-dimensional audio client application programs by use of a code base common to multiple audio server computers. The 3DAudio library calls vendor-specific audio client libraries and currently supports the AuSIM Gold-Server and Lake Huron audio servers. 3DAudio library routines contain common functions for (1) initiation and termination of a client/audio server session, (2) configuration-file input, (3) positioning functions, (4) coordinate transformations, (5) audio transport functions, (6) rendering functions, (7) debugging functions, and (8) event-list-sequencing functions. The 3DAudio software is written in the C++ programming language and currently operates under the Linux, IRIX, and Windows operating systems.

Rizzi, Stephen A.↗
DOE OSTI2026

Thermal Management Solution for an Integrated Outer-Rotor Motor Drive: Opportunities and Challenges

This work highlights an integrated thermal management solution for the outer-rotor motor (ORM) drive. The integrated ORM drive utilizes water-ethylene glycol coolant for power electronics and stator cooling. Air cooling is used for rotor laminations, magnets and outer-rotor structures, and the rotor shaft. To fully understand the performance of the integrated ORM drive and thermal management coupling effects, a full drive conjugate heat transfer model has been developed to investigate coupled cooling performance of various components of the ORM drive. Various motor rotational speeds, power output scenarios, and cooling options for the integrated ORM drive have been investigated. The model estimates the operating window for the ORM drive while keeping component operating temperatures below prescribed limits. The model also highlights the importance of windage losses at higher rotational speeds for this ORM design, which involves higher rotor surface area per unit width of the rotor. Different designs are also investigated, particularly focusing on rotor cooling with air either naturally induced by rotor spin or forced airflow with the help of a blower, to circumvent challenges imposed by higher windage losses. The work highlights motor rotational speed limitations and the need for potential liquid cooling options for desired rotor performance at higher rotational speeds. Liquid cooling for the rotor may even become more critical for nonuniform rotor-stator gaps, leading to even higher and uneven windage losses across the full circumference of the motor, consequentially, more heating for the rotor.

30 DIRECT ENERGY CONVERSION↗
NASA NTRS1992

Collision avoidance of a multiple degree of redundancy manipulator operating through a window

The problem of collision-free operation of a multiple-degree-of-redundancy manipulator operating through a window is addressed. An efficient gradient projection optimization scheme is presented for the kinematic control of manipulators with multiple degrees of redundancy. This scheme was developed for dextrous robotic and telerobotic applications in space station construction as well as in congested shop floor environment. A performance criterion is defined to maximize the shortest distances between the manipulator links and the edges of the window. Effectiveness of this scheme and the validity of the performance criterion are verified through simulations of the seven-degree-of-freedom NASA Laboratory Telerobotic Manipulator.

Zghal, H.↗
NASA NTRSDate not supplied

Spacecraft Window Design from a Thermal Perspective

This paper gives a rudimentary introduction to spacecraft window design from a thermal engineering perspective. Windows have always been integral parts of all of NASA’s flown, crewed spacecraft missions and will continue to be included on future crewed vehicles. They are part of the primary structure and require high structural reliability. Often neglected by non-thermal engineers, there are important thermal impacts to including windows on a spacecraft design. Thermal radiation from the sun, planetary bodies, or other vehicles can enter the vehicle and heat the interior. Windows can also be heat leaks to space during cold operations. Windows may also serve as part of the vehicle Thermal Protection System for entry vehicles. Like all other parts of the spacecraft, windows must be included in thermal models to predict temperatures; the transparency of pane materials and the addition of coatings increase modeling complexity. Testing of windows is also more complex than typical spacecraft structure due to the uniqueness of each pane (depending on material), transmittance, and the challenge of physically measuring window material temperature during testing.

Cheyn L Worn↗
NASA NTRSDate not supplied

Spacecraft Window Design From A Thermal Perspective

This paper gives a rudimentary introduction to spacecraft window design from a thermal engineering perspective. Windows have always been integral parts of all of NASA’s flown, crewed spacecraft missions and will continue to be included on future crewed vehicles. They are part of the primary structure and require high structural reliability. Often neglected by non-thermal engineers, there are important thermal impacts to including windows on a spacecraft design. Thermal radiation from the sun, planetary bodies, or other vehicles can enter the vehicle and heat the interior. Windows can also be heat leaks to space during cold operations. Windows may also serve as part of the vehicle Thermal Protection System for entry vehicles. Like all other parts of the spacecraft, windows must be included in thermal models to predict temperatures; the transparency of pane materials and the addition of coatings increase modeling complexity. Testing of windows is also more complex than typical spacecraft structure due to the uniqueness of each pane (depending on material), transmittance, and the challenge of physically measuring window material temperature during testing.

Thermal↗
DOE OSTI2024

WEST full tungsten operation with an ITER grade divertor

The mission of WEST (tungsten-W Environment in Steady-state Tokamak) is to explore long pulse operation in a full tungsten (W) environment for preparing next-step fusion devices (ITER and DEMO) with a focus on testing the ITER actively cooled W divertor in tokamak conditions. Following the successful completion of phase 1 (2016-2021), phase 2 started in December 2022 with the lower divertor made entirely of actively cooled ITER-grade tungsten mono-blocks. A boronization prior the first plasma attempt allowed for a smooth startup with the new divertor. Despite the reduced operating window due to tungsten, rapid progress has been made in long pulse operation, resulting in discharges with a pulse length of 100 s and an injected energy of around 300 MJ per discharge. Plasma startup studies were carried out with equatorial boron nitride limiters to compare them with tungsten limiters, while Ion Cyclotron Resonance Heating assisted startup was attempted. High fluence operation in attached regime, which was the main thrust of the first campaigns, already showed the progressive build up of deposits and appearance of dust, impacting the plasma operation as the plasma fluence increased. In total, the cumulated injected energy during the first campaigns reached 43 GJ and the cumulated plasma time exceeded 5 h. Demonstration of controlled X-Point Radiator regime is also reported, opening a promising route for investigating plasma exhaust and plasma-wall interaction issues in more detached regime. This paper summarises the lessons learned from the manufacturing and the first operation of the ITER-grade divertor, describing the progress achieved in optimising operation in a full W environment with a focus on long pulse operation and plasma wall interaction.

70 PLASMA PHYSICS AND FUSION TECHNOLOGY↗
NASA NTRS2004

Updated System-Availability and Resource-Allocation Program

A second version of the Availability, Cost and Resource Allocation (ACARA) computer program has become available. The first version was reported in an earlier tech brief. To recapitulate: ACARA analyzes the availability, mean-time-between-failures of components, life-cycle costs, and scheduling of resources of a complex system of equipment. ACARA uses a statistical Monte Carlo method to simulate the failure and repair of components while complying with user-specified constraints on spare parts and resources. ACARA evaluates the performance of the system on the basis of a mathematical model developed from a block-diagram representation. The previous version utilized the MS-DOS operating system and could not be run by use of the most recent versions of the Windows operating system. The current version incorporates the algorithms of the previous version but is compatible with Windows and utilizes menus and a file-management approach typical of Windows-based software.

Viterna, Larry↗
NASA NTRS2005

Component-Based Visualization System

A software system has been developed that gives engineers and operations personnel with no "formal" programming expertise, but who are familiar with the Microsoft Windows operating system, the ability to create visualization displays to monitor the health and performance of aircraft/spacecraft. This software system is currently supporting the X38 V201 spacecraft component/system testing and is intended to give users the ability to create, test, deploy, and certify their subsystem displays in a fraction of the time that it would take to do so using previous software and programming methods. Within the visualization system there are three major components: the developer, the deployer, and the widget set. The developer is a blank canvas with widget menu items that give users the ability to easily create displays. The deployer is an application that allows for the deployment of the displays created using the developer application. The deployer has additional functionality that the developer does not have, such as printing of displays, screen captures to files, windowing of displays, and also serves as the interface into the documentation archive and help system. The third major component is the widget set. The widgets are the visual representation of the items that will make up the display (i.e., meters, dials, buttons, numerical indicators, string indicators, and the like). This software was developed using Visual C++ and uses COTS (commercial off-the-shelf) software where possible.

Delgado, Francisco↗
DOE OSTI2026

Solvent–Diluent Engineering of Normal-Concentration Organosulfur Electrolytes for High-Voltage Lithium-Ion Batteries

Enabling high‑voltage batteries depends critically on rational electrolyte design. Conventional carbonate electrolytes with LiPF 6 suffer from insufficient oxidative stability, motivating the use of lithium bis(fluorosulfonyl)imide (LiFSI) for its superior high‑temperature and high‑voltage performance. However, LiFSI is relatively costly, and its electrolytes often require high concentrations to suppress aluminum current collector corrosion in cathode architectures and to adequately passivate electrode interfaces. Here, a low‑concentration LiFSI electrolyte is realized by combining a high‑voltage organosulfur solvent, ethyl methyl sulfone (EMS), with a non‑solvating fluorinated diluent, fluorobenzene (FB). Extended cycling of LiNi 0.8 Mn 0.1 Co 0.1 O 2 (NMC811) full cells to 4.5 V reveals substantial long‑term performance advantages over conventional carbonate electrolytes. Comparison with a popular cyclic sulfone, tetramethylene sulfone (TMS), shows that ring‑containing structures such as TMS strongly influence passivation behavior, ultimately limiting performance and narrowing the viable operating window. Overall, EMS is identified as a uniquely stable solvent for LiFSI‑based electrolytes operating at moderately high voltages.

Dato, Michael A. [Argonne National Laboratory (ANL↗