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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 523 records · Page 29

Utilizing Modal Testing for Monitoring the Structural Health of Wind Tunnel Facility Hardware

The 10- by 10-Foot Abe Silverstein Supersonic Wind Tunnel (10×10) is the largest and fastest wind tunnel facility at NASA’s Glenn Research Center(GRC) and is specifically designed to test supersonic propulsion components from inlets and nozzles to full-scale jet and rocket engines[1]. Recently, a critical part of the wind tunnel failed and required a redesign before reintegrating into the facility. The design requirements of this new component required that clearances between large metallic components exist, which have the potential for undesirable nonlinear dynamics to occur, in particular rattling. Rattling is feared to occur when the wind tunnel is being operated in certain flow regimes that induce cyclic aero loads on the new component near its natural frequencies. This paper describes the approach taken to better understand and resolve this vibration problem using modal testing. A modal test was developed and executed by GRC’s Structural Dynamics Lab to quantify the modal parameters of the structure, namely which specific excitation frequencies caused the structure to rattle. These results were shared with facility operators as frequency ranges that should be avoided to ensure maximum lifespan of the new structure. Additional means of structural health monitoring (SHM) as well as Vortex shedding are briefly discussed in this paper.

Pederson, Kenneth↗

Space Radiation and Impact on Instrumentation Technologies

Understanding the interactions of the Sun, Earth and other natural and man-made objects in the solar system with the space radiation environment is crucial for improving activities of humans on Earth and in space. An important component of understanding these interactions is their effects on the instrumentation required in the exploration of air and space. NASA's Glenn Research Center (GRC) fills the role of developing supporting technologies to enable improved instruments for space science missions, as well as improved instruments for aeronautics and ground-based applications. In this review, the space radiation environment and its effects are outlined, as well the impact it has on instrumentation and the technology that GRC is developing to improve performance for space science.

Wrbanek, John D.↗

On Development of Three-Dimensional Visualization Capabilities in Glenn Research Center Communication Analysis Suite

With NASA’s upcoming mission to return to the Moon sustainably by 2024 and using that success as a means to step onto the barren world of Mars, it remains more important than ever to conduct research and planning as thoroughly and efficiently as possible. In a mission as complex as landing humans onto another celestial body, a network of orbiting satellites and ground stations must accurately and reliably communicate with each other, enabling crucial data communications throughout the mission. Visualizing this important data communication increases the understanding of the data and can accelerate analyses efforts. The purpose of this software development is to create an interactive visualization with data taken MATLAB® scripts in the GRC Communication Analysis Suite that is easy to understand, can show all necessary data, and display the data accurately. The main types of data to visualize are from the State Propagation, Line of Sight and Dynamic Link Margin scripts. These all show positions and orbits of satellites and ground stations, while the Line of Sight data shows when they have the ability to communicate with each other based on their respective antenna positions and fields of view. Additionally, the Dynamic Link Margin mode color-codes the communication link performance onto the Line of Sight access lines. Visualization requires a graphics language that is easily accessible, has the needed features, and able to easily read data produced by the GRC Communication Analysis Suite MATLAB® scripts. ThreeJS, a graphics library for Web Graphics Library, coded in JavaScript was selected for the visualization. The next part of the software development was to move the data from MATLAB® to the JavaScript. The best way to accomplish this was to implement a MATLAB® function converting the output data of the scripts to a JavaScript Object Notation file. A key part of the development was creating the visualization within JavaScript and ThreeJS to visualize any combination of planets, moons, orbits, satellites, ground stations, line of sight links, and handle future features without changing major parts of the code. The current visualization capability runs directly from MATLAB®, and can dynamically create any scene. This software development currently supports the lunar communications analysis underway by NASA, and can be easily expanded upon in the future to aid any analysis requirements to help plan current and future space missions.

Visualization↗

Pumping Loss of Shrouded Meshed Spur Gears

High speed rotorcraft transmissions are subject to load-independent power losses consisting of drag loss and pumping loss. Tightly conforming shrouds enclosing the transmission gears are often incorporated to reduce the drag component of the total load-independent losses. However, tightly conforming axial shrouds can result in an increase in the pumping loss component. Quantifying the pumping loss of shrouded gear transmissions has been the subject of many studies. This study presents a new approach for estimating pumping loss based on the concept of swept volume and examines the applicability of the approach to various shroud configurations.The drag loss and pumping loss of a shrouded spur gear pair has been determined through testing using the NASAGlenn Research Center (GRC) Gear Windage Test Facility.The results from this testing have been compared to theoretical results using the formulations presented in this study. In addition, computational fluid dynamic (CFD) analysis has been conducted for the various shroud configurations tested at NASA GRC. The results from the CFD analysis confirm the theoretical and empirical results and provide insight into the applicability of the swept volume approach for estimating pumping power loss of shrouded gear transmissions.

Michael J. Hurrell↗

Rotating Balance Design Methodology

Several upcoming wind tunnel turbofan tests at NASA Glenn Research Center (GRC) require new rotating balances to meet test needs. As the name implies, a rotating balance rotates with the fan providing direct thrust and torque measurements to estimate fan efficiency and performance. One main feature of the new rotating balances requested by GRC, is a more compact design compatible with high bypass fans that are of interest for gains in fuel efficiency. In support of this measurement need, NASA Langley Research Center (LaRC) developed an understanding and methodology for the design of two-component rotating balances. During the development of the methodology, a thorough FEA analysis was conducted, torque analysis of laboratory test specimens, and a study of analytical models were investigated. This presentation will summarize the developed rotating balance design methodology that is detailed in a NASA Technical Memorandum. This TM will detail the analysis required to design, and fabricate a two-component spoke-type rotating balance.

Kenneth Toro↗

Solar White Thermal Coating for Cryogenic Propulsion Systems

NASA is currently conducting research into the potential of storing cryogenic fluid in low Earth orbit (LEO). Having cryogenic propellant readily available for high-performance propulsion systems can be very beneficial for deep space missions in the near future. One of the key challenges to storing cryogenic fluid in LEO is minimizing boil-off. To address the challenge, NASA is evaluating new concepts in thermal insulation. One recent experimental study evaluated the feasibility of using Yttrium Oxide (Y2O3), formed into tiles or spray coating that can potentially be used as a thermal coating for cryogenic propellant storage applications in deep space. Due to its temperature and wavelength dependent optical properties, this “solar white” material can reflect a vast majority of the Sun’s radiative energy while having a very high infrared emissivity for rejecting heat to deep space. As a part of the material development and proof of concept testing, multiple tests have been run at KSC and GRC to demonstrate the performance of the material. At GRC, the tests were run using the Deep Space Solar Simulator (DS3) which contains a thermal vacuum chamber in which the solar white sample was exposed to a deep space environment (< 10 K, optically dense walls) while under full illumination via solar lamp. In order to improve the use of the test results and apply them to spacecraft, there is a need to be able to model the material properties within NASA’s standard thermal modeling tools. As such, it was set out to verify a thermal model of one of the experiments using Thermal Desktop with Sinda. The thermal model of the DS3 test setup includes the solar white sample along with a solar lamp simulator capable of outputting heat at varying wavelengths. The model was developed in order to validate the test results and also to help predict results that will be obtained in future tests. This paper will review the modeling methods and thermal analysis results for various test cases that were run within the DS3 facility.

Cryogenic↗

Lessons Learned in Concurrent Mission and Systems Design at NASA Glenn Research Center: Almost Fifteen Years of the Compass Team

This paper is a retrospective of the lessons learned during the almost 15-year history of the Compass concurrent mission and systems design team at NASA’s Glenn Research Center (GRC). It examines the key factors in the team’s evolution from a temporary group gathered to perform a single study to the successful, sustainable team it is today. Compass is a matrixed team of experts with various technical backgrounds and personalities. They collaborate over a two-week period either physically in a dedicated meeting space, or virtually to design a space system (Spacecraft, stage, science package, etc). Over the years, because of the rapid nature of the design studies, the team leadership has iterated on the optimal team member personality makeup, facility elements and tools as well as NASA GRC management support necessary to lead to sustained success.

systems engineering↗

Mechanically Strong Polyimide Aerogels (MSPA) As Multifunctional Acoustic Insulation

Aerogel Technologies has an exclusive license from NASA to commercialize polyimide aerogels developed at NASA GRC. They combine low density, low thermal conductivity, high specific strength, and soundproofing properties in a single material envelope. Aerogel Technologies and NASA GRC are working together to optimize the properties for lightweight, structural material for vibro-acoustic mitigation for launch vehicles, with the goal of achieving TRL 6 by the conclusion of the project.

polyimide aerogel↗

Modal Test and Model Correlation of NASA Plum Brook Station Mechanical Vibration Facility Head Expander –Lessons Learned from the Perspective of an Early-Career Engineer

In preparation for the Sierra Nevada Corporation’s (SNC) Dream Chaser spacecraft vibration test campaign at the Mechanical Vibration Facility (MVF) at NASA Plum Brook Station (PBS) in Sandusky, Ohio, a test-verified model of MVF is needed in order to be able to perform accurate pretest analysis used for determining response limits and abort levels. MVF was designed to vibration test MPCV Orion and was used to perform the system level vibration test of the European Service Module Structural Test Article (E-STA) in 2016. MVF is comprised of an 18 ft diameter annulus table that is driven with sixteen hydraulic vertical actuator assemblies and four hydraulic horizontal actuator assemblies, which allow it to perform single axis vibration testing in the vertical axis and in each of the two orthogonal horizontal axes without the need for reconfiguring the test article. A head expander for the MVF Table has been designed and built that fills in the center opening providing a continuous flat mounting surface with a maximum diameter of 16.25feet that expands the vibration testing capabilities of MVF. The MVF Table with this head expander will be used during the SNC Dream Chaser spacecraft vibration test campaign. Therefore, a critical element in a test-verified model of the MVF will be a test correlated finite element model (FEM) of the head expander. To obtain this, engineers from the Structural Dynamics Lab (SDL) at NASA Glenn Research Center (GRC) in Cleveland, Ohio performed a modal pretest analysis, conducted a modal test in July 2019, and most recently correlated the head expander finite element model to the modal test data up to 300 Hz. From the initial test preparations to the final delivery of a correlated finite element model, all efforts mentioned were led by the same early-career engineers at NASA GRC. From the viewpoint of an early-career engineer, lessons learned about modal pretest analysis, modal testing, and finite element model correlation of the MVF Table expander head will be presented and discussed. This will include the importance of understanding the limitations of using uncorrelated finite element models in the modal pretest analysis and planning, the importance of orthogonality metrics in judging adequacy and accuracy of test mode shapes, and the importance of having the FEM match the as built hardware in the model correlation effort.

Emma L Pierson↗

Convertor Development for Dynamic Radioisotope Power Systems

Dynamic power conversion technologies are being developed for future space science and exploration missions by NASA’s Radioisotope Power Systems (RPS) Program, in collaboration with the U.S. Department of Energy (DOE). The Dynamic Radioisotope Power Systems (DRPS) Project is working to mature dynamic power convertors and controllers for infusion into a potential future flight generators.1,2 Maturation of power conversion technologies is being executed by the DRPS Project and the Thermal Energy Conversion Branch, located at NASA’s Glenn Research Center (GRC), and includes convertor technology development contracts and in-house controller development. The convertor technology development contracts consist of three contractors tasked to design, fabricate, and complete performance testing before the units are delivered to GRC for independent assessment. All contractors have completed convertor designs and are fabricating convertors to enable performance testing, while one has demonstrated initial performance of their design. The contractors also have provided generator conceptual designs, which utilize their respective convertor technologies being developed.

Dynamic↗

Electric Aircraft Thermal Management Using a Two-Phase Heat Transport System with Solid-State Thermal Switching Capability

Advanced Cooling Technologies, Inc. (ACT) is collaborating with NASA Glenn Research Center (GRC) to develop a heat pipe-based thermal delivery system to efficiently manage the waste heat generated onboard an electric aircraft. The heat pipe system will interface with NASA GRC’s thermoacoustic heat pump in order to recycle waste heat by transporting thermal energy to various end users onboard the aircraft. This paper discusses the layout of theoretical heat pipe networks for a MW-class commercial electric aircraft. This is followed by a discussion of progress made on the development of a novel two-phase heat transport system with solid-state thermal switching and control capabilities.

Exergy↗

Experimental, Computational, Theoretical and Analytical Investigation of Flow Boiling in Reduced Gravity

Two-phase thermal management systems are far superior to their single-phase counterparts because of their ability to capitalize on the coolant’s both sensible and latent heats, thereby yielding orders of magnitude higher heat transfer coefficients and smaller system footprints. A vital knowledge necessary for their implementation in future space systems is performance in microgravity. Long-duration microgravity experiments are necessary to obtain reliable databases, which would then be used to build reliable predictive tools. To achieve this goal, investigators at the Purdue University Boiling and Two-Phase Flow Laboratory (PU-BTPFL) and the NASA Glenn Research Center (NASA-GRC) have been collaborating towards the development of the Flow Boiling and Condensation Experiment (FBCE) and eventual execution onboard the International Space Station (ISS). FBCE has now matured to a point where it is ready for transport to the ISS, where first tests will be conducted using the Flow Boiling Module (FBM). In preparation for the ISS tests, a series of pre-launch Mission Sequence Tests (MSTs) was performed at GRC in Earth gravity with FBM mounted in a vertical upflow orientation using n-perfluorohexane as working fluid. The pre-launch tests included variations of flow rate, surface heat flux, inlet conditions, and both single-sided and double-sided wall heating. This presentation will summarize experimental results from these tests as well as both analytic and theoretical tools for prediction of two-phase heat transfer coefficient and critical heat flux (CHF). Also discussed will be an assessment of predictive accuracy of these tools against the experimental data.

Mission Sequence tests↗

Managing Spacecraft Risk With Space Environments Testing Via Process Safety Management At The NASA Neil A. Armstrong Test Facility

The NASA Glenn Research Center’s Neil A. Armstrong Test Facility (GRC-ATF) is home to several unique, world class aerospace test facilities, including the In-Space Propulsion (ISP) Facility. The ISP Facility is NASA’s largest chamber designed to store and transfer large quantities of liquid hydrogen and liquid oxygen; and is designed to support developmental testing of upper stage chemical propulsion systems as well as fully integrated stages. The facility is also capable of providing thermal-vacuum simulation services to support testing of aerospace hardware, Cryogenic Fluid Management (CFM) systems and other In-Space propulsion programs. The U.S. Occupational Safety and Health Administration’s (OSHA) Process Safety Management (PSM) of Highly Hazardous Chemicals Standard (29 CFR 1910.119) is an analytical tool focused on preventing the release of chemicals and other energy sources. In a short timeframe, GRC-ATF was required to restore a PSM Program at the Facility. Although the summarized work is specific to the ground testing of rockets and space vehicles, the ISP Facility is used to verify system level requirements, some of these are safety requirements, and thus key to managing risks in space.

Safety↗

Advanced Electric Propulsion System (AEPS) Enabling a Sustainable Return to the Lunar Surface through NASA Gateway

NASA continues to evolve a human exploration approach for beyond low-Earth orbit. The center of this approach is NASA’s Gateway that is envisioned to provide a maneuverable outpost in lunar orbit to extend human presence in deep space and expand on NASA exploration goals. The Gateway represents the initial step in NASA’s architecture for human cislunar operations, lunar surface access and missions to Mars. NASA announced at the May 2020 NASA Advisory Council’s Human Explorations and Operations Committee a new plan that calls for launching the first two elements of Gateway as a co-manifested mission in the late 2023 timeframe [2]. Launching the Power and Propulsion Element (PPE) and the Habitation and Logistics Outpost (HALO) together reduces mission risk, utilizes the PPE high-powered Electric Propulsion (EP) system to transport both elements to the lunar orbit, and reduces overall cost. NASA and Maxar Technologies have a commercial partnership to develop and demonstration a high-powered Solar Electric Propulsion (SEP) spacecraft [3, 4]. The PPE is baselined to include three 12.5-kW Advanced Electric Propulsion Systems (AEPS) and four 6-kW Hall thrusters, currently under development by Maxar, for a total beginning of life propulsion power of over 48-kW [5]. High-power solar electric propulsion is one of the key technologies that has been prioritized because of its significant exploration benefits, specifically, for missions beyond low Earth orbit. Spacecraft size and mass are currently dominated by onboard chemical propulsion systems and propellants that may constitute more than 50 percent of spacecraft mass. This impact can be substantially reduced through the utilization of SEP, due to its higher specific impulse and lower propellant load required to meet the equivalent mission delta-V. Studies performed for NASA’s HEOMD and Science Mission Directorate (SMD) have demonstrated that 40-kW-class SEP provides the necessary capabilities that would enable near term and future architectures, and science missions [6]. Accordingly, NASA has been developing a 12 kW Hall thruster electric propulsion thruster that can serve as the building block for a 40-kW-class SEP capability. The AEPS development, led by the NASA Glenn Research Center (GRC) and the Jet Propulsion Laboratory (JPL), began with the maturation of the high-power Hall thruster. The technology development work has transitioned to AR via a competitive procurement selection for the AEPS contract in May 2016. Management of the AEPS contract is being led by NASA GRC with funding from NASA’s Science Technology Mission Directorate (STMD) under the Technology Demonstration Missions (TDM) program. NASA continues to support the AEPS development leveraging in-house expertise, plasma modeling capability, and world-class test facilities.

AEPS↗

Upgrades to the Single Stage Axial Compressor and Fan Facility For Low Pressure Ratio and Boundary Layer Ingesting Fan Research

Next generation aircraft engine efficiency goals will be met through high bypass ratio engines. To achieve these goals, a combination of small core and low pressure ratio fan technologies will be necessary. Additionally, advanced propulsion air-frame integration concepts, such as boundary layer propulsion, and distributed electrically driven fans with short inlets or wing integration strategies, are beginning to be investigated for their potential fuel burn savings. In order to realize the potential fuel savings from these technologies, it is necessary to have testing capabilities for the components. The NASA Glenn Research Center (GRC) Single StageAxial Fan and Compressor Facility (also called the GRC W-8Facility) has recently undergone several significant upgrades in order to effectively test low pressure ratio fans and various inlet distortions. This paper will outline various challenges to testing low pressure ratio fans and the methods implemented to ensure that the W-8 facility is capable of performing these tests and acquiring high quality data. The upgrades include significant pip-ing upgrades to reduce pressure loss and turbulence, capability for inlet total pressure and swirl distortion, increased test section length including a longer shaft, a two component balance, an up-graded rotating data system, and a new temperature characterization to reduce uncertainties in thermocouple measurements

W-8 Facility↗

Upgrades to the Single Stage Axial Compressor and Fan Facility For Low Pressure Ratio and Boundary Layer Ingesting Fan Research

Next generation aircraft engine efficiency goals will be met through high bypass ratio engines. To achieve these goals, a combination of small core and low pressure ratio fan technologies will be necessary. Additionally, advanced propulsion airframe integration concepts, such as boundary layer propulsion, and distributed electrically driven fans with short inlets or wing integration strategies, are beginning to be investigated for their potential fuel burn savings. In order to realize the potential fuel savings from these technologies, it is necessary to have testing capabilities for the components. The NASA Glenn Research Center (GRC) Single Stage Axial Fan and Compressor Facility (also called the GRC W-8 Facility) has recently undergone several significant upgrades in order to effectively test low pressure ratio fans and various inlet distortions. This paper will outline various challenges to testing low pressure ratio fans and the methods implemented to ensure that the W-8 facility is capable of performing these tests and acquiring high quality data. The upgrades include significant piping upgrades to reduce pressure loss and turbulence, capability for inlet total pressure and swirl distortion, increased test section length including a longer shaft, a two component balance, an upgraded rotating data system, and a new temperature characterization to reduce uncertainties in thermocouple measurements.

W-8 facitlity↗

Wide Band Gap Radiation Detectors for Deep Space Science

Understanding how the Sun, Earth, and other objects in the solar system interact with the space radiation environment is crucial for improving activities of humans on Earth and in space. Low-power, low-noise, multidirectional robust detectors for detecting ions with a wide range of mass and energies will provide a more complete understanding of space environment physics. To meet these challenges, new ion detectors based on wide band gap (WBG) semiconductors are being developed for integration on a variety of deep space platforms. NASA Glenn Research Center (GRC) is applying its expertise and facilities in harsh environment instrumentation to develop supporting technologies to enable improved instruments for space science missions. New detector technologies being developed at GRC include SiC solid-state devices as practical robust, thermally stable large area detectors for LET measurements in compact, stacked charged particle telescope. The low-noise, thermally stable nature of the WBG detectors allows a small multidirectional array of charged particle telescopes to be packed in a 6U CubeSat without active cooling for operation in lunar orbit or deep space. Using a full variety of different WBG detectors, an extremely compact instrument to provide multi-directional, comprehensive (composition, velocity, and direction) in-situ measurements of heavy ions in space plasma environments can be realized.

ion detectors↗

Analytical Study of a Cryogenic Thermal Control Coating

This study focuses on the analysis of a cryogenic thermal control coating designed to reflect most of the Sun’s irradiance while emitting long wavelength radiation, thus enabling propulsion systems to maintain cryogenic temperatures while in deep space. This “solar white” coating is composed of yttrium oxide (Y2O3) which has properties that are well-suited for cryogenic propellant storage applications. To conduct proof of concept and material development, many tests have been run at both NASA Kennedy Space Center (KSC) and Glenn Research Center (GRC) to demonstrate the performance of the coating in the cryogenic regime in both powder and ceramic forms. At GRC, the Deep Space Solar Simulator (DS3) was used to run thermal vacuum tests where the coating was exposed to a deep space environment (~10 K) with some tests conducted under the illumination of a solar lamp. Using the test data, a thermal model of the DS3 test setup was developed to correlate the test results to predict the optical properties of the coating. Once the optical properties were determined, an additional thermal model, based on previous work by R.C. Young quist et al., was developed to verify the performance of a theoretical lunar, cryogenic propellant depot. The latter thermal model also demonstrates the usage of the HLS-UG-001 Human Landing System Lunar Thermal Analysis Guidebook published to baseline Artemis-related lunar studies.

Cryogenic↗