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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 955 records · Page 53
All sourcesNASA NTRSDOE OSTI
NASA NTRS2014

The Situational Awareness Sensor Suite for the ISS (SASSI): A Mission Concept to Investigate ISS Charging and Wake Effects

The complex interaction between the International Space Station (ISS) and the surrounding plasma environment often generates unpredictable environmental situations that affect operations. Examples of affected systems include extravehicular activity (EVA) safety, solar panel efficiency, and scientific instrument integrity. Models and heuristically‐derived best practices are well‐suited for routine operations, but when it comes to unusual or anomalous events or situations, especially those driven by space weather, there is no substitute for real‐time monitoring. Space environment data collected in real‐time (or near‐real time) can be used operationally for both real‐time alarms and data sources in assimilative models to predict environmental conditions important for operational planning. Fixed space weather instruments mounted to the ISS can be used for monitoring the ambient space environment, but knowing whether or not (or to what extent) the ISS affects the measurements themselves requires adequate space situational awareness (SSA) local to the ISS. This paper presents a mission concept to use a suite of plasma instruments mounted at the end of the ISS robotic arm to systematically explore the interaction between the Space Station structure and its surrounding environment. The Situational Awareness Sensor Suite for the ISS (SASSI) would be deployed and operated on the ISS Express Logistics Carrier (ELC) for long‐term "survey mode" observations and the Space Station Remote Manipulator System (SSRMS) for short‐term "campaign mode" observations. Specific areas of investigation include: 1) ISS frame and surface charging during perturbations of the local ISS space environment, 2) calibration of the ISS Floating Point Measurement Unit (FPMU), 3) long baseline measurements of ambient ionospheric electric potential structures, 4) electromotive force-induced currents within large structures moving through a magnetized plasma, and 5) wake‐induced ion waves in both electrostatic (i.e. particles) and electromagnetic modes. SASSI will advance the understanding of plasma‐boundary interaction phenomena, demonstrate a suite a sensors acting in concert to provide effective SSA, and validate and/or calibrate existing ISS space environment instruments and models.

Krause, L. Habash↗
NASA NTRS2016

The Plant Phenology Monitoring Design for the National Ecological Observatory Network

Phenology is an integrative science that comprises the study of recurring biological activities or events. In an era of rapidly changing climate, the relationship between the timing of those events and environmental cues such as temperature, snowmelt, water availability, or day length are of particular interest. This article provides an overview of the observer-based plant phenology sampling conducted by the U.S. National Ecological Observatory Network (NEON), the resulting data, and the rationale behind the design. Trained technicians will conduct regular in situ observations of plant phenology at all terrestrial NEON sites for the 30-yr life of the observatory. Standardized and coordinated data across the network of sites can be used to quantify the direction and magnitude of the relationships between phenology and environmental forcings, as well as the degree to which these relationships vary among sites, among species, among phenophases, and through time. Vegetation at NEON sites will also be monitored with tower-based cameras, satellite remote sensing, and annual high-resolution airborne remote sensing. Ground-based measurements can be used to calibrate and improve satellite-derived phenometrics. NEON's phenology monitoring design is complementary to existing phenology research efforts and citizen science initiatives throughout the world and will produce interoperable data. By collocating plant phenology observations with a suite of additional meteorological, biophysical, and ecological measurements (e.g., climate, carbon flux, plant productivity, population dynamics of consumers) at 47 terrestrial sites, the NEON design will enable continental-scale inference about the status, trends, causes, and ecological consequences of phenological change.

phenology↗
NASA NTRS2016

Numerical Simulation of a High-Lift Configuration Embedded with High Momentum Fluidic Actuators

Numerical simulations have been performed for a vertical tail configuration with deflected rudder. The suction surface of the main element of this configuration, just upstream of the hinge line, is embedded with an array of 32 fluidic actuators that produce oscillating sweeping jets. Such oscillating jets have been found to be very effective for flow control applications in the past. In the current paper, a high-fidelity computational fluid dynamics (CFD) code known as the PowerFLOW R code is used to simulate the entire flow field associated with this configuration, including the flow inside the actuators. A fully compressible version of the PowerFLOW R code valid for high speed flows is used for the present simulations to accurately represent the transonic flow regimes encountered in the flow field due to the actuators operating at higher mass flow (momentum) rates required to mitigate reverse flow regions on a highly-deflected rudder surface. The computed results for the surface pressure and integrated forces compare favorably with measured data. In addition, numerical solutions predict the correct trends in forces with active flow control compared to the no control case. The effect of varying the rudder deflection angle on integrated forces and surface pressures is also presented.

Vatsa, Veer N.↗
NASA NTRS2016

Using Computational Fluid Dynamics and Experiments to Design Sweeping Jets for High Reynolds Number Cruise Configurations

The application of a sweeping jet actuator to a circulation control system was initiated by a risk reduction series of experiments to optimize the authority of a single sweeping jet actuator. The sweeping jet design was integrated into the existing Fundamental Aerodynamic Subsonic Transonic- Modular Active Control (FAST-MAC) model by replacing the steady blowing system with an array of thirty-nine sweeping jet cartridges. A constant slot height to wing chord ratio was similar to the steady blowing configuration resulting in each actuator having a unique in size for the sweeping jet configuration. While this paper will describe the scaling and optimization of the actuators for future high Reynolds number applications, the major focus of this effort was to target the transonic flight regime by increasing the amplitude authority of the actuator. This was accomplished by modifying the diffuser of the sweeping jet actuator, and this paper highlights twelve different diffuser designs. The experimental portion of this work was completed in the NASA Langley National Transonic Facility.

Jones, Gregory S.↗
NASA NTRS2016

UAS Integration in the NAS Project: Flight Test 3 Data Analysis of JADEM-Autoresolver Detect and Avoid System

The Unmanned Aircraft Systems Integration in the National Airspace System project, or UAS Integration in the NAS, aims to reduce technical barriers related to safety and operational challenges associated with enabling routine UAS access to the NAS. The UAS Integration in the NAS Project conducted a flight test activity, referred to as Flight Test 3 (FT3), involving several Detect-and-Avoid (DAA) research prototype systems between June 15, 2015 and August 12, 2015 at the Armstrong Flight Research Center (AFRC). This report documents the flight testing and analysis results for the NASA Ames-developed JADEM-Autoresolver DAA system, referred to as 'Autoresolver' herein. Four flight test days (June 17, 18, 22, and July 22) were dedicated to Autoresolver testing. The objectives of this test were as follows: 1. Validate CPA prediction accuracy and detect-and-avoid (DAA, formerly known as self-separation) alerting logic in realistic flight conditions. 2. Validate DAA trajectory model including maneuvers. 3. Evaluate TCAS/DAA interoperability. 4. Inform final Minimum Operating Performance Standards (MOPS). Flight test scenarios were designed to collect data to directly address the objectives 1-3. Objective 4, inform final MOPS, was a general objective applicable to the UAS in the NAS project as a whole, of which flight test is a subset. This report presents analysis results completed in support of the UAS in the NAS project FT3 data review conducted on October 20, 2015. Due to time constraints and, to a lesser extent, TCAS data collection issues, objective 3 was not evaluated in this analysis.

flight test↗
NASA NTRS2016

Global Positioning System Energetic Particle Data: The Next Space Weather Data Revolution

The Global Positioning System (GPS) has revolutionized the process of getting from point A to point Band so much more. A large fraction of the worlds population relies on GPS (and its counterparts from other nations) for precision timing, location, and navigation. Most GPS users are unaware that the spacecraft providing the signals they rely on are operating in a very harsh space environment the radiation belts where energetic particles trapped in Earths magnetic field dash about at nearly the speed of light. These subatomic particles relentlessly pummel GPS satellites. So by design, every GPS satellite and its sensors are radiation hardened. Each spacecraft carries particle detectors that provide health and status data to system operators. Although these data reveal much about the state of the space radiation environment, heretofore they have been available only to system operators and supporting scientists. Research scientists have long sought a policy shift to allow more general access. With the release of the National Space Weather Strategy and Action Plan organized by the White House Office of Science Technology Policy (OSTP) a sample of these data have been made available to space weather researchers. Los Alamos National Laboratory (LANL) and the National Center for Environmental Information released a months worth of GPS energetic particle data from an interval of heightened space weather activity in early 2014 with the hope of stimulating integration of these data sets into the research arena. Even before the public data release GPS support scientists from LANL showed the extraordinary promise of these data.

Knipp, Delores J.↗
NASA NTRS2017

NASA's Space Launch System: Deep-Space Delivery for SmallSats

Designed for human exploration missions into deep space, NASA's Space Launch System (SLS) represents a new spaceflight infrastructure asset, enabling a wide variety of unique utilization opportunities. While primarily focused on launching the large systems needed for crewed spaceflight beyond Earth orbit, SLS also offers a game-changing capability for the deployment of small satellites to deep-space destinations, beginning with its first flight. Currently, SLS is making rapid progress toward readiness for its first launch in two years, using the initial configuration of the vehicle, which is capable of delivering more than 70 metric tons (t) to Low Earth Orbit (LEO). On its first flight, an uncrewed test of the Orion spacecraft into distant retrograde orbit around the moon, accompanying Orion on SLS will be 13 small-satellite secondary payloads, which will deploy in cislunar space. These secondary payloads will include not only NASA research, but also spacecraft from industry and international partners and academia. The payloads also represent a variety of disciplines including, but not limited to, studies of the moon, Earth, sun, and asteroids. The Space Launch System Program is working actively with the developers of the payloads toward vehicle integration. Following its first flight and potentially as early as its second, SLS will evolve into a more powerful configuration with a larger upper stage. This configuration will initially be able to deliver 105 t to LEO, and will continue to be upgraded to a performance of greater than 130 t to LEO. While the addition of the more powerful upper stage will mean a change to the secondary payload accommodations from those on the first launch, the SLS Program is already evaluating options for future secondary payload opportunities. Early discussions are also already underway for the use of SLS to launch spacecraft on interplanetary trajectories, which could open additional opportunities for small satellites. This presentation will include an overview of the SLS vehicle and its capabilities, including the current status of progress toward first launch. It will also explain the opportunities the vehicle offers for small satellites, including an overview of the CubeSat manifest for Exploration Mission-1 in 2018 and a discussion of future capabilities.

Robinson, Kimberly F.↗
NASA NTRS2019

The Arctic-Boreal vulnerability experiment model benchmarking system

NASA's Arctic-Boreal Vulnerability Experiment (ABoVE) integrates field and airborne data into modeling and synthesis activities for understanding Arctic and Boreal ecosystem dynamics. The ABoVE Benchmarking System (ABS) is an operational software package to evaluate terrestrial biosphere models against key indicators of Arctic and Boreal ecosystem dynamics, i.e.: carbon biogeochemistry, vegetation, permafrost, hydrology, and disturbance. The ABS utilizes satellite remote sensing data, airborne data, and field data from ABoVE as well as collaborating research networks in the region, e.g.: the Permafrost Carbon Network, the International Soil Carbon Network, the Northern Circumpolar Soil Carbon Database, AmeriFlux sites, the Moderate Resolution Imaging Spectroradiometer, the Orbiting Carbon Observatory 2, and the Soil Moisture Active Passive mission. The ABS is designed to be interactive for researchers interested in having their models accurately represent observations of key Arctic indicators: a user submits model results to the system, the system evaluates the model results against a set of Arctic-Boreal benchmarks outlined in the ABoVE Concise Experiment Plan, and the user then receives a quantitative scoring of model strengths and deficiencies through a web interface. This interactivity allows model developers to iteratively improve their model for the Arctic-Boreal Region by evaluating results from successive model versions. We show here, for illustration, the improvement of the Lund–Potsdam–Jena-Wald Schnee und Landschaft (LPJwsl) version model through the ABoVE ABS as a new permafrost module is coupled to the existing model framework. The ABS will continue to incorporate new benchmarks that address indicators of Arctic-Boreal ecosystem dynamics as they become available.

ABoVE↗
NASA NTRSDate not supplied

Energy Efficient Large-Scale Storage of Liquid Hydrogen

World’s largest LH2storage tanks constructed in mid-1960s at NASA/KSC. These vacuum-perlite insulated tanks, still in service today, are 3,200 m3capacity (ea.). In 2018, construction began on an additional 4,700 m3LH2storage tank at LC-39B•NASA’s new Space Launch System (SLS) heavy lift rocket for Artemis program holds 2,033 m3of LH2in its 8.4-m diameter by 40-m height. Two new energy-efficient technologies are included: glass bubbles insulation system and an Integrated Refrigeration and Storage (IRAS) heat exchanger for passive + active thermal control:•Evacuated glass bubbles insulation system has been shown to reduce LH2boiloff by 46% versus perlite in field demonstrations. Controlled storage via IRAS, when fully implemented, will provide full control of ullage pressure, zero boiloff, and even production of densified LH22CEC-2021

cryogenics↗
NASA NTRSDate not supplied

COSPAR Workshop Series on Refining Planetary Protection Requirements for Human Missions to Mars

COSPAR and its space agency partners are supporting a multi-year stepwise process devel-oping needed approaches to address planetary protection requirements for human missions beyond Earth orbit. The objective is to support incremental development from the current qualitative COSPAR planetary protection “Principles and Guidelines for Human Missions to Mars” to quantitative implementable planetary protection requirements for such future mis-sions. The workshops and meetings in this series have involved participants from NASA, ESA, JAXA and other national space agencies, as well as the scientific/technical community, and commercial/private enterprise stakeholders, based around three main topic areas: Microbial and Human Health Monitoring; Spacecraft Technology and Operations, and; Natural Trans-port of Contamination at Mars. This presentation provides a status update on the findings of the COSPAR Meetings on this topic to date. First, the identification and prioritization of knowledge gaps will be summarized. Next, where a knowledge gap is to be addressed by new measurements, example descriptions of measurements needed to close the knowledge gaps (and instruments necessary to make those measurements) will be discussed. Where the knowledge gaps closure is based on Agency policy decisions, the scope of the decision-making parameters and process will be described. Lastly, the presentation will consider how the findings of the study series can be integrated into current and future space agency and COSPAR activities.

J. Andy Spry↗
NASA NTRS2022

Mars 2020 Perseverance Rover Surface Operations Commissioning Phase Overview

This paper presents work done by the Mars 2020 Project to plan, test, and execute the Mars 2020 Perseverance Rover surface operations commissioning phase. Immediately after the successful landing of Mars 2020 Perseverance rover at Jezero Crater on February 18, 2021, the rover autonomously initiated mission critical commanding necessary to transition the vehicle from a Cruise/EDL to Surface operations configuration. This began the surface operations commissioning phase, referred to as Surface Operations Transition (SOX). The objective of SOX phase is to establish vehicle health and safety and to verify that the operational characteristics of the vehicle, now operating in the Martian environment, are as-expected and safe to proceed into nominal operations. The SOX commissioning phase is organized into six logical sub-phases occurring in the following chronological order; (1) SOX1a, (2) FSW Transition, (3) SOX1b, (4) SOX2a, (5) Heli, (6) SOX2b. In total, the SOX commissioning phase was expected to take up-to 111 sols (Martian days). The Perseverance rover is an extremely complex, highly-integrated, robotic system-of-systems that requires numerous activities to incrementally and methodically verify their safe operations. This paper will discuss the development process used to plan, test, and execute the SOX commissioning phase for Mars 2020 Perseverance rover surface operations. We will discuss key challenges associated with SOX development as well as actual operations execution experience.

Koch, Justin↗
NASA NTRSDate not supplied

Space Crop Production Gaps and Challenges

As astronauts venture farther from Earth, and stay for longer periods, the space food system will increase in importance. Crop production can supplement a pre-packaged space diet to provide nutrition and dietary variety for space crews. In future missions, bioregenerative approaches may be used to generate a larger percentage of the diet, as well as help to reduce life support system burdens and resupply from Earth. Plants may also provide behavioral health benefits to crew members living in the isolated, confined environment of a space habitat. A number of unique challenges exist for growth of plants in microgravity and on other reduced gravity surfaces like the moon and Mars. Testing plant growth inside the Veggie and Advanced Plant Habitat (APH) chambers on the International Space Station is allowing us to understand the impacts of gravity and spaceflight on crop growth, nutritional content, acceptability, and the importance of plants to astronauts living and working away from Earth. We are also gaining a better understanding of food safety concerns and the behavior of space plant microbiomes and plant pathogens, but major gaps in knowledge remain. As we move from research towards operational space crop production to enable exploration, there are numerous gaps in technology, knowledge, and practice related to space crop growth that must be addressed. Research and development in key focus areas such as effective water and nutrient delivery at variable gravity levels, autonomous plant health monitoring, growth system cleaning and disinfection, and selection of ideal space crops are needed to fill these gaps. Breeding or engineering custom space crops may impact areas including plant growth and development, plant physiology, produce nutrition, organoleptic acceptability, and post-harvest characteristics, and these may further enable space crop production scenarios. Space crop challenges are multifaceted and require diverse interdisciplinary teams working together to develop effective solutions. Solving these requires an array of skill sets from across the biological and physical sciences, engineering, and human social sciences. Solutions to help ensure food security off-Earth may also translate to more sustainable terrestrial crop production approaches, and regular dialog between industry, academia, and government organizations working in related fields benefit all. Additional help can come from engagement with student researchers at various levels through courses, participatory science projects, and open science activities which can provide useful data. Global coordination and integration between space agencies and partners will be essential.

Gioia Donna Massa↗
NASA NTRSDate not supplied

Space Crop Production Gaps and Challenges

As astronauts venture farther from Earth, and stay for longer periods, the space food system will increase in importance. Crop production can supplement a pre-packaged space diet to provide nutrition and dietary variety for space crews. In future missions, bioregenerative approaches may be used to generate a larger percentage of the diet, as well as help to reduce life support system burdens and resupply from Earth. Plants may also provide behavioral health benefits to crew members living in the isolated, confined environment of a space habitat. A number of unique challenges exist for growth of plants in microgravity and on other reduced gravity surfaces like the moon and Mars. Testing plant growth inside the Veggie and Advanced Plant Habitat (APH) chambers on the International Space Station is allowing us to understand the impacts of gravity and spaceflight on crop growth, nutritional content, acceptability, and the importance of plants to astronauts living and working away from Earth. We are also gaining a better understanding of food safety concerns and the behavior of space plant microbiomes and plant pathogens, but major gaps in knowledge remain. As we move from research towards operational space crop production to enable exploration, there are numerous gaps in technology, knowledge, and practice related to space crop growth that must be addressed. Research and development in key focus areas such as effective water and nutrient delivery at variable gravity levels, autonomous plant health monitoring, growth system cleaning and disinfection, and selection of ideal space crops are needed to fill these gaps. Breeding or engineering custom space crops may impact areas including plant growth and development, plant physiology, produce nutrition, organoleptic acceptability, and post-harvest characteristics, and these may further enable space crop production scenarios. Space crop challenges are multifaceted and require diverse interdisciplinary teams working together to develop effective solutions. Solving these requires an array of skill sets from across the biological and physical sciences, engineering, and human social sciences. Solutions to help ensure food security off-Earth may also translate to more sustainable terrestrial crop production approaches, and regular dialog between industry, academia, and government organizations working in related fields benefit all. Additional help can come from engagement with student researchers at various levels through courses, participatory science projects, and open science activities which can provide useful data. Global coordination and integration between space agencies and partners will be essential.

Gioia Massa↗
NASA NTRS2024

Cooperative and Non-Cooperative UAS Detection

This paper describes a system that enhances airspace situational awareness by detecting and identifying Unmanned Aerial Systems (UAS). This multi-domain solution tracks both cooperative scientific flights as well as non-cooperative intrusions from "bad actors." The system supports a critical push towards safety within NASA’s advanced air mobility mission. After surveying the existing technologies at Langley Research Center, the radar and visual systems were chosen for the primary and secondary detection mechanisms, respectively. These systems were tuned an upgraded to become more sensitive to UAS activity. Additionally, a Remote Identification receiver was procured and integrated into the flight surveillance system.

Lucas Barduson↗
NASA NTRSDate not supplied

Developmental and Cryogenic Thermal Vacuum (TVAC) Testing Lessons Learned

Developmental thermal vacuum (TVAC) testing is a critical step in maturing hardware designs and validating performance prior to flight qualification. Unlike qualification or acceptance testing, developmental testing provides flexibility to explore design margins, uncover integration challenges, and refine test approaches before formal verification activities begin. This presentation highlights the value of developmental testing while sharing common pitfalls encountered during developmental TVAC campaigns. Lessons learned from hands-on testing experience, including extensive developmental testing at cryogenic temperatures, will be shared in this presentation. Topics include test planning and preparation, instrumentation strategies, contamination control considerations, troubleshooting unexpected anomalies, and approaches for staying on schedule while meeting test objectives. The audience will gain practical insights and best practices that can improve test efficiency, reduce risk, and enhance the overall success of future developmental TVAC efforts.

Mackenzie Byrnes↗
NASA NTRS1999

Rocket-Based Combined-Cycle Propulsion Technology for Access-to-Space Applications

NASA's Office of Aero-Space Technology (OAST) established three major goals, referred to as, "The Three Pillars for Success". The Advanced Space Transportation Program Office (ASTP) at the NASA's Marshall Space Flight Center (MSFC) in Huntsville, Ala. focuses on future space transportation technologies under the "Access to Space" pillar. One of the main activities over the past three years has been on advancing the hydrogen fueled rocket-based combined cycle (RBCC) technologies. The RBCC effort that was completed early this year was the initial step leading to flight demonstrations of the technology for space launch vehicle propulsion. Aerojet and Boeing-Rocketdyne designed, built and ground tested their RBCC engine concepts. In addition, ASTROX, Georgia Institute of Technology, McKinney Associates, Pennsylvania State University (PSU), and University of Alabama in Huntsville conducted supporting activities. The RBCC activity included ground testing of components (e.g., injectors, thrusters, ejectors and inlets) and integrated flowpaths. Inlet testing was performed at the Lewis Research Center's 1 x 1 wind tunnel. All direct connect and free-jet engine testing were conducted at the GASL facilities on Long Island, New York. Testing spanned the Mach range from sea level static to Mach 8. Testing of the rocket-only mode, simulating the final phase of the ascent mission profile, was also performed. The originally planned work on these contracts was completed in 1999. Follow-on activities have been initiated for both hydrogen and hydrocarbon fueled RBCC concepts. Studies to better understand system level issues with the integration of RBCC propulsion with earth-to-orbit vehicles have also been conducted. This paper describes the status, progress and future plans of the RBCC activities funded by NASA/MSFC with a major focus on the benefits of utilizing air-breathing combined-cycle propulsion in access-to-space applications.

Hueter, Uwe↗
NASA NTRS1971

Earth orbital experiment program and requirements study, volume 1, sections 1 - 6

A reference manual for planners of manned earth-orbital research activity is presented. The manual serves as a systems approach to experiment and mission planning based on an integrated consideration of candidate research programs and the appropriate vehicle, mission, and technology development requirements. Long range goals and objectives for NASA activities during the 1970 to 1980 time period are analyzed. The useful and proper roles of manned and automated spacecraft for implementing NASA experiments are described. An integrated consideration of NASA long range goals and objectives, the system and mission requirements, and the alternative implementation plans are developed. Specific areas of investigation are: (1) manned space flight requirements, (2) space biology, (3) spaceborne astronomy, (4) space communications and navigation, (5) earth observation, (6) supporting technology development requirements, (7) data management system matrices, (8) instrumentation matrices, and (9) biotechnology laboratory experiments.

Source record↗
NASA NTRS2007

Human Activity Behavior and Gesture Generation in Virtual Worlds for Long- Duration Space Missions

A virtual worlds presentation technique with embodied, intelligent agents is being developed as an instructional medium suitable to present in situ training on long term space flight. The system combines a behavioral element based on finite state automata, a behavior based reactive architecture also described as subsumption architecture, and a belief-desire-intention agent structure. These three features are being integrated to describe a Brahms virtual environment model of extravehicular crew activity which could become a basis for procedure training during extended space flight.

Sierhuis, Maarten↗