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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 775 records · Page 43
All sourcesNASA NTRSDOE OSTI
NASA NTRS2018

Fiber-Based Laser Transmitter Technology Maturation for Spectroscopic Measurements from Space

NASA's Goddard Space Flight Center has been developing lidar to remotely measure CO2 in the Earth's atmosphere. We have advanced the tunable laser technology to enable high-fidelity measurements from space. In this paper, we will report on the progress of fiber-based, 1.57-micron wavelength, laser transmitter that has demonstrated the optical performance required for a low earth orbiting instrument. The Laser transmitter has been packaged and is undergoing environmental testing to demonstrate its technology readiness for space.

Stephen, Mark↗
NASA NTRS2018

Progress and Plans for a US Laser System for the LISA Mission

NASA Goddard Space Flight Center is developing a master oscillator power amplifier (MOPA) laser transmitter for the ESA-led Laser Interferometer Space Antenna (LISA) mission. Taking advantage of our space laser experience and the emerging telecom laser technology, we are developing a full laser system for the LISA mission. Our research effort has included both master oscillator (MO) and power amplifier (PA) developments, and their environmental testing and reliability for space flight. Our current baseline for the MO is a low-mass, compact micro NPRO (m-NPRO) laser. The amplifier uses a robust mechanical design based on fiber components. We have performed laser system noise tests by amplitude- and frequency-stabilizing the PA output. We will describe our progress and plans to demonstrate a TRL 6 laser system, which is an essential step toward qualifying lasers for space applications, by 2021.

lasers↗
NASA NTRS2018

Progress and Plans for a US Laser System for the LISA Mission

NASA Goddard Space Flight Center is developing a master oscillator power amplifier (MOPA) laser transmitter for the ESA-led Laser Interferometer Space Antenna (LISA) mission. Taking advantage of our space laser experience and the emerging telecom laser technology, we are developing a full laser system for the LISA mission. Our research effort has included both master oscillator (MO) and power amplifier (PA) developments, and their environmental testing and reliability for space flight. Our current baseline for the MO is a low-mass, compact micro non-planar ring oscillator (m- NPRO) laser. The amplifier uses a robust mechanical design based on fiber components. We have performed laser system noise tests by amplitude- and frequency-stabilizing the PA output. We will describe our progress and plans to demonstrate a TRL 6 laser system, which is an essential step toward qualifying lasers for space applications, by 2021.

Numata, Kenji↗
NASA NTRS2018

Thin-Film Solar Arrays for Small Spacecraft

The use of thin-film based solar arrays for space applications has long been recognized as an advantageous power generation option. Thinner materials yield a mass savings, equating to lighter launch loads, larger arrays, and/or more payload allocation. Further, their mechanical flexibility lends itself well to stowage and deployment schemes, allowing for a vast improvement to both specific power (W/kg - watts per kilogram) as well as stowed power density (W/m3 - watts per cubic meter). A key application of thin-film space solar arrays is in the small satellite community; where spacecraft are largely power-starved. Their need for higher power generation coupled with the extreme mass and volume restrictions of the small spacecraft bus is driving the requirement for advanced solar arrays. And, when coupled with the relatively short operational requirements (e.g. less than 2 years) of small spacecraft, yields the perfect application for these thin-film arrays. In this presentation, NASA’s recent work on developing the Lightweight Integrated Solar Array and anTenna (LISA-T - also known as Lightweight Integrated Solar Array and Transceiver)), a thin-film solar array for small spacecraft, will be discussed. The array configuration will be shown alongside bench top deployment videos, a summary of environmental testing to date, and forward plans to a flight test. Advanced, robotic additive manufacturing of the thin-film web will also be discussed.

Carr, John A.↗
NASA NTRS2018

Single Photon HgCdTe Avalanche Photodiode and Integrated Detector Cooler Assemblies for Space Lidar Applications

A linear mode photon counting HgCdTe avalanche photodiode (APD) focal plane array (FPA) detector was developed for space lidar applications. An integrated detector cooler assembly (IDCA) was manufactured using a miniature Stirling cooler. The HgCdTe APD demonstrated a greater than 60% photon detection efficiency from 0.9 to 4.3 μm wavelength and a dark count rate less than 250,000/s. The IDCA cooled the FPA to 110K from ambient room temperature at a total electrical power of 7 W. The IDCA has passed environmental tests, including vibration, thermal cycling and thermal vacuum tests.

Sun, Xiaoli↗
NASA NTRS2019

Qualification of a Hybrid Propulsion System for the Mars Ascent Vehicle

Technology for a hybrid based propulsion system is being developed to support a potential Mars Sample Return campaign. A Mars Ascent Vehicle (MAV) concept for launching samples off of Mars, and delivering them to orbit for further transport to Earth may utilize hybrid propulsion due to the predicted favorable low temperature characteristics and high performance of this option. However, the hybrid option is still undergoing technology development to demonstrate these capabilities. Once development of a capable hybrid propulsion system is proven, further work will be required. This will include environmental testing relative to the mission, and integration with the vehicle reaction control systems and payload. Qualification of such a system will be a significant effort. It will require specialized procurements for the propellants and environments involved, and further testing of the more specialized designs. This paper details an estimate of the tasks required to complete development efforts from Technical Readiness Level 5 (TRL5) through qualification. A success based program was formulated to reach the required performance metrics sufficient for a standard Preliminary Design Review (PDR). Using task level inputs from team members cost and schedule were conceived for continued progress to Critical Design Review (CDR), then through Qualification.

Prince, Andrew↗
NASA NTRS2019

Ion Propulsion for Solar System Exploration

NASA's Evolutionary Xenon Thruster (NEXT) is ready for transition-to-flight. The thruster has completed all qualification-level environmental testing, and has demonstrated a xenon propellant throughput, total impulse, and total operating hours greatly in excess of anticipated planetary science mission requirements, and exceeding that achieved by any other thruster technology in the history of electric propulsion. NEXT is the next generation system, a natural progression in technology from that implemented successfully on the Deep-Space one and Dawn missions, developed at NASA's Glenn Research Center in Cleveland, Ohio. The first implementation of NEXT will be on NASA 's Double Asteroid Redirection Test (DART). DART will be the first demonstration of the kinetic impact technique to change the motion of an asteroid in space. The DART mission is in Phase C, led by Johns Hopkins University Applied Physics Laboratory. The DART spacecraft will utilize the NASA Evolutionary Xenon Thruster solar electric propulsion system as its primary in-space propulsion system. By utilizing NEXT, DART is able to gain significant flexibility to the mission timeline and launch window, as well as decrease in launch vehicle cost. This presentation will review NASA's investment strategy in electric propulsion _ in particular gridded ion thruster technology _ as it applies to solar system exploration. Results obtained from implementing this technology on Deep-Space one and Dawn will be reviewed. Mission studies which highlight the impacts of the NEXT technology will be discussed, and near-term proposed and scheduled missions including DART and CAESAR (Comet Astrobiology Exploration Sample Return) will be reviewed.

Electric Propulsion↗
NASA NTRS2019

Simulation of HyMETS Flowfield Around Baby-SPRITE Entry Probe

Arc-jets are unique facilities used in research, development, and evaluation of high-temperature thermal protection systems for hypersonic vehicles and planetary entry systems. Thermochemical non-equilibrium computational fluid dynamics simulations have been carried out for the Hypersonic Materials Environmental Test System arc-jet facility to determine the size of a capsule model before arc-jet testing by better understanding of the physical phenomena. The results show the effect of the test article geometry and the importance of high-quality grids for accurate solutions. Accurate computational modeling of hypersonic flow fields inside arc-jets under simulated planetary entry conditions would help improve the design of thermal protection systems that may enable human exploration of the Moon, Mars, and beyond.

Ventura Diaz, Patricia↗
NASA NTRS2019

HgCdTe Avalanche Photodiode Array Detectors with Single Photon Sensitivity and Integrated Detector Cooler Assemblies for Space Lidar Applications

A HgCdTe avalanche photodiode (APD) focal plane array assembly with linear mode photon-counting capability has been developed for space lidar applications. An integrated detector cooler assembly (IDCA) has been built using a miniature Stirling cooler. A microlens array has been included to improve the fill factor. The HgCdTe APD has a spectral response from 0.9- to 4.3-μm wavelengths, a photon detection efficiency as high as 70%, and a dark count rate of <250 kHz at 110 K. The mass of the IDCA is 0.8 kg and the total electrical power consumption is about 7 W. The HgCdTe APD arrays have been characterized at NASA Goddard Space Flight Center. A series of environmental tests have been conducted for the IDCAs, including vibration, thermal cycling, and thermal vacuum tests. A description of the device and the test results at NASA are given in this paper.

Sun, Xiaoli↗
NASA NTRS2020

Nitric Oxide Laser-Induced Fluorescence Rotational Thermometry in a Hypersonic Non-Equilibrium Flow

Spatially-resolved nitric oxide (NO) planar laser-induced fluorescence (PLIF) rotational thermometry was performed on a Mach 5 non-equilibrium flow around a blunt-body specimen in the Hypersonic Materials Environmental Test System (HyMETS) arc-heat wind tunnel at the NASA Langley Research Center. Transitions within the (0,0) band in the A(exp⁡ 2)∑(sup⁡ +) - X(exp⁡ 2)Π system of NO were excited with a 10 Hz pulsed ultra-violet laser. A multi-line fitting algorithm was applied to the PLIF spectra and transitions were filtered based on an iterative method that maximizes thermometry accuracy. NO PLIF thermometry results are compared to non-equilibrium computational fluid dynamics (CFD) simulations reported in the literature. Differences between the experiment and CFD are quantified for the free-stream, post-shock, shear-layer, and expansion-fan regions of the flow. Potential sources of error, applicable to both the CFD and experiment, are discussed.

Connor C McDougall↗
NASA NTRSDate not supplied

Characterizing the Effects of Thermal Profile and Gas Environment on the Heat Treatment of JSC-1A Lunar Simulant Using Combined Thermogravimetry and Mass Spectroscopy

As NASA strives towards a long duration presence on the Moon, it has become increasingly important to learn how to better utilize resources from the lunar surface for everything from habitats, vehicle infrastructure, and chemical extraction. To that end, a variety of lunar simulants have been sourced from terrestrially available volcanic minerals and glass as Apollo regolith is a finite resource unavailable for experimentation needing large masses. However, while mineralogy and chemical composition can approach that of lunar material in these simulants, there are still distinct non-lunar phases such as hydrates, carbonates, sulfates, and clays that can cause simulants to behave distinctly non-lunar in a variety of processing conditions that would ideally be applied to lunar material. Notably, severe glassy bubbling has been documented in a variety of vacuum sintering experiments on JSC-1A lunar Maria simulant heated via microwaves. The origins of this outgassing have not been well understood, but are normally attributed to the decomposition of non-lunar contaminates intrinsic to virtually all terrestrially sourced simulants. As such, a series of controlled environmental tests were performed to ascertain the origins of the high temperature outgassing and to develop heat treatments that can drive JSC-1A closer to lunar composition and behavior. It was found that in JSC-1A that distinct gas evolutions of water, carbon dioxide, and sulfur dioxide occur in both inert gas and vacuum. Additionally, the presence of hydrogen during heat treatments was shown to dramatically change gas evolutions, leading to distinctly more lunar-like composition and behavior from JSC-1A simulant.

sinter↗
NASA NTRSDate not supplied

Characterizing the Effects of Thermal Profile and Gas Environment on the Heat Treatment of JSC-1A Lunar Simulant Using Combined Thermogravimetry and Mass Spectroscopy

As NASA strives towards a long duration presence on the Moon, it has become increasingly important to learn how to better utilize resources from the lunar surface for everything from habitats, vehicle infrastructure, and chemical extraction. To that end, a variety of lunar simulants have been sourced from terrestrially available volcanic minerals and glass as Apollo regolith is a finite resource unavailable for experimentation needing large masses. However, while mineralogy and chemical composition can approach that of lunar material in these simulants, there are still distinct non-lunar phases such as hydrates, carbonates, sulfates, and clays that can cause simulants to behave distinctly non-lunar in a variety of processing conditions that would ideally be applied to lunar material. Notably, severe glassy bubbling has been documented in a variety of vacuum sintering experiments on JSC-1A lunar Maria simulant heated via microwaves. The origins of this outgassing have not been well understood, but are normally attributed to the decomposition of non-lunar contaminates intrinsic to virtually all terrestrially sourced simulants. As such, a series of controlled environmental tests were performed to ascertain the origins of the high temperature outgassing and to develop heat treatments that can drive JSC-1A closer to lunar composition and behavior. It was found that in JSC-1A that distinct gas evolutions of water, carbon dioxide, and sulfur dioxide occur in both inert gas and vacuum. Additionally, the presence of hydrogen during heat treatments was shown to dramatically change gas evolutions, leading to distinctly more lunar-like composition and behavior from JSC-1A simulant.

sinter↗
NASA NTRS2021

Status of the James Webb Space Telescope Mission

The James Webb Space Telescope ( Webb) is the largest space telescope realized to-date, with a 6.5 m segmented primary mirror that must be folded to fit within its Ariane 5 launcher fairing. This infrared telescope is passively cooled using a five-layer sunshield that will keep the optical telescope and its four science instruments in the shade throughout the lifetime of the mission in an L2 orbit. Webb's science instruments include near- and mid­ infrared imagers and spectrometers that cover the spectral range from 0.6-28.5 µm. The Webb mission has a long history with numerous first of its kind technology developments, ground support equipment innovations, and algorithmic characterization advances. This conference proceeding summarizes the technical progress over the past two years, from the Spacecraft Element environmental testing to the Observatory integration and testing, and the final Observatory test plans leading up to launch, on-orbit commissioning, and science operations.

Michael W McElwain↗
NASA NTRS2022

Development of LISA Laser System at NASA

NASA Goddard Space Flight Center (GSFC) is developing a master oscillator power amplifier (MOPA) laser transmitter for the Laser Interferometer Space Antenna (LISA) mission. The laser transmitter is one of the potential contributions to the LISA mission from NASA. Our development effort has included a master oscillator (MO), a power amplifier (PA), a frequency reference system (FRS), a power monitor detector (PMON), and laser electronics module (LEM). We are working on their design, performance evaluation, environmental testing, and reliability testing for space flight. We have built TRL 4 laser optical modules based on the MO and PA, which meets most performance requirements. One of the TRL 4 laser optical modules has been delivered to ESA for independent evaluation. TRL 6 versions of MO and PA are being built and evaluated at GSFC. TRL 5 and 6 versions of laser electronics are under development. In this paper, we will describe our progress to date and plans to demonstrate and deliver a TRL 6 laser demonstrator system to ESA by 2024.

LISA, Space Lasers↗
NASA NTRS2022

Aerothermodynamic Measurements of Hypersonic Non-Equilibrium Flows

High enthalpy arc-jets are unique facilities particularly suited for producing complex flows in the aerospace field, such as the aerothermodynamics of a re-entry vehicle. Arc-jets are often used to evaluate important design factors that include heat shield materials and vehicle design. Characterization of these facilities is important, as studies often aim to match specific in-flight environments during experiments. Due to the complex environment produced by an arc-jet, with effects such as thermodynamic and chemical non-equilibrium occurring in the flow, characterization experiments are significantly more difficult than in conventional blow-down wind tunnels. The current work aims to characterize an arc-jet facility through spatially-resolved measurements of flow unsteadiness, temperature, and velocity. To achieve this goal, a non-intrusive imaging technique called “planar laser-induced fluorescence” was performed in the NASA Langley Hypersonic Materials Environmental Test System arc-jet facility. The experimental data was analysed to produce the quantitative measurements in multiple regions of the flow around a blunt body specimen. A three-temperature low fidelity numerical solver was created to simulate the flow in order to investigate thermal non-equilibrium effects occurring outside the imaging region in the arc-jet nozzle. Unsteadiness in the test section of the arc-jet was minimized by analyzing a subset of data assessing the gas injection configuration. Radial velocity, rotational temperature and translational temperature measurements are provided that can be used to validate future computational studies. The temperature measurements revealed rotational non-equilibrium occurring behind the bow-shock near the specimen surface. Computational results show the facility is capable of producing thermal non-equilibrium flow in the arc-jet nozzle. This work provides the first experimental and computational evidence of thermal trans-rotational non-equilibrium occurring in multiple regions of this arc-jet facility. Significant improvements to the methodology are also identified as recommendations for future arc-jet characterization studies.

Laser induced fluorescence↗
NASA NTRSDate not supplied

The P-Band Space Exploration Synthetic Aperture Radar (SESAR)

The Space Exploration Synthetic Aperture Radar (SESAR) is a P-band (435 MHz) radar instrument for planetary applications capable of measuring the surface and subsurface of planetary bodies at full polarimetry and at meter-scale resolution. These measurements can reveal important information about the surface evolution and geologic history of the planetary bodies, and help identify buried resources for future explorers. SESAR’s architecture is based on a low power, lightweight, beamforming design, specifically developed to meet stringent requirements of planetary instruments. The SESAR developmental effort, carried out at NASA/GSFC, designed and built a prototype SAR instrument, and environmentally tested it, with the goal of maturing the SESAR technology readiness level for upcoming planetary mission opportunities.

Rafael F Rincon↗
NASA NTRS2023

Uncertainty Analysis of Slug Calorimeters in the HyMETS Arc-Jet Facility

The objective of this work is to perform an uncertainty analysis of the deduced stagnation heat flux environment on a slug calorimeter for conditions that span the performance envelope of the Hypersonic Materials Environmental Test System arc-jet facility located at NASA Langley Research Center. Analytical solutions are developed for boundary-value problems on the slug element accounting for non-ideal effects, including spatial variation in the slug heat flux, multi-dimensional thermal conduction, and back-face losses, which departs from the state-of-the-art method derived from the American Society of Testing and Materials. Boundary-value problem definitions are informed by preliminary finite element thermal analysis of the slug calorimeter assembly (including both slug and housing) and just the slug element. The analytical solutions are presented in a general sense and in a truncated form from error analysis. Results are shown in optimizing and validating the analytical models against available slug back-face thermal data. The optimization results indicate that the appropriate epistemic uncertainty of the deduced stagnation heat flux on the slug calorimeter is at most±2.5% for both a high-and low-enthalpy test condition. In addition, a numerical approach is used to determine the aleatory (probabilistic) uncertainty component in the slug stagnation heat flux by applying a marching least-squares slope routine through the steady-state portion of the slug back-face thermal response. Results indicate a compromise between the number of samples and the filter frequency of slug back-face thermal data points when evaluating the standard deviation of the deduced stagnation heat flux statistics. When combining the mixed uncertainty, both aleatory and epistemic, the interval of uncertainty in the deduced stagnation heat flux is determined to be up to ±4%, which is at least a 60% reduction from the standard uncertainty used in the state-of-the-art method.

uncertainty↗