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All sourcesNASA NTRSDOE OSTI
NASA NTRSDate not supplied

Predicting SLS Launch Environment using a Novel Multiphase Formulation

Powerful acoustic waves generated during ignition of launch vehicles may be dangerous to the vehicle, its payload, or the surrounding structures. The water-based Ignition Overpressure and Sound Suppression (IOP/SS) system at Kennedy Space Center’s (KSC) Launch Complex 39B (LC-39B) will be used to protect the Space Launch System (SLS) from the acoustic vibrations generated during launch. The IOP/SS system uses enormous amounts of water to dampen and attenuate these sound waves. To better understand the launch environment risks and to study the effectiveness of the IOP/SS system it is desirable to have time-accurate unsteady simulations of the vehicle ignition with water-based sound suppression. This paper presents results obtained with a novel, high-order accurate, and robust numerical method designed for simulating compressible multiphase flows. A positivity-preserving finite difference scheme is utilized which is formally high-order accurate and also provably robust. Robustness is critical due to the extreme nature of the flow which exhibits highly nonlinear shock and rarefaction waves interacting with liquid-gas interfaces with density ratios of the order of 1000:1. Furthermore, the high-order accuracy (and the high resolution property) is desirable for predicting wave phenomena like IOP waves since the signal can be resolved accurately and propagated long distances with fewer grid points. This finite-difference method was developed using NASA’s Launch, Ascent, and Vehicle Aerodynamics (LAVA) Cartesian immersed boundary framework. We present a validation case by applying our solver to the SLS Scale Model Acoustic Test (SMAT). The SLS SMAT is a well-instrumented 5% scale model test meant to represent the SLS at NASA KSC’s LC-39B pad. Scale IOP tests were performed with and without the sound suppression water and included many sensors which recorded the pressure waves produced during ignition. For this validation case we conduct two simulations, likewise with and without sound suppression water, and compare the SLS SMAT pressure sensor signals with our numerical signals at identical locations. Following this validation case we present a study of the SLS launch environment to examine engineering safety concerns about the mobile launch pad. Engineers at KSC redesigned the main flame deflector at LC-39B anticipating the increased loads from the SLS and to repair damage from prior Shuttle missions. This deflector redesign made use of surface pressure and temperature data from LAVA full-scale SLS simulations without the sound suppression system. The engineers were questioning the possibility of increased pressure loads on the underside of the mobile launcher due to the water in the flame trench. Based on the results established in our simulations of the SLS SMAT, we performed updated calculations for SLS at LC-39B with and without water systems active to assess the readiness of the launch pad for Artemis I launch. Our results show that the IOP/SS system is effective at reducing the overpressure signal and overall sound pressure levels felt by the vehicle and additionally that the pressure loads experienced by the mobile launcher (ML) during engine startup is not increased by the presence of water.

EGS↗
NASA NTRS2011

Water Impact Prediction Tool for Recoverable Rockets

Reusing components from a rocket launch can be cost saving. NASA's space shuttle system has reusable components that return to the Earth and impact the ocean. A primary example is the Space Shuttle Solid Rocket Booster (SRB) that descends on parachutes to the Earth after separation and impacts the ocean. Water impact generates significant structural loads that can damage the booster, so it is important to study this event in detail in the design of the recovery system. Some recent examples of damage due to water impact include the Ares I-X First Stage deformation as seen in Figure 1 and the loss of the SpaceX Falcon 9 First Stage.To ensure that a component can be recovered or that the design of the recovery system is adequate, an adequate set of structural loads is necessary for use in failure assessments. However, this task is difficult since there are many conditions that affect how a component impacts the water and the resulting structural loading that a component sees. These conditions include the angle of impact with respect to the water, the horizontal and vertical velocities, the rotation rate, the wave height and speed, and many others. There have been attempts to simulate water impact. One approach is to analyze water impact using explicit finite element techniques such as those employed by the LS-Dyna tool [1]. Though very detailed, this approach is time consuming and would not be suitable for running Monte Carlo or optimization analyses. The purpose of this paper is to describe a multi-body simulation tool that runs quickly and that captures the environments a component might see. The simulation incorporates the air and water interaction with the component, the component dynamics (i.e. modes and mode shapes), any applicable parachutes and lines, the interaction of winds and gusts, and the wave height and speed. It is capable of quickly conducting Monte Carlo studies to better capture the environments and genetic algorithm optimizations to reproduce a flight.

Rooker, William↗
NASA NTRS1996

An Infrared Study of the Juggler Nebula

This work is an examination of the infrared reflection nebula surrounding a protostellar source, IRS 1, in the CRL 2136 region at 2.2, 3.08, and 3.45 micron. The greatest absorption due to water ice occurs within 5 arcsec (10,000 AU, D = 2000 pc) of IRS 1. The water ice absorption decreases with increasing radius from IRS 1. This Tau(sub ice) structure suggests that the water ice is primarily associated with IRS 1. The flux from IRS 1 has a (2.2) - (3.45) color of 5, much redder than the nebula. The color structure combined with the Tau(sub ice) structure suggests the presence of an icy-dusty disk around IRS 1 orientated NE to SW. Radio CO maps presented by Kastner et al. reveal a molecular outflow orientated perpendicular to the disk. The south and east reflection lobes line the conical cavity created by the blueshifted molecular outflow.

Holbrook, J. C.↗
NASA NTRS2009

Engineered Structured Sorbents for the Adsorption of Carbon Dioxide and Water Vapor from Manned Spacecraft Atmospheres: Applications and Testing 2008/2009

This paper describes efforts to improve on typical packed beds of sorbent pellets by making use of structured sorbents and alternate bed configurations to improve system efficiency and reliability. The benefits of the alternate configurations include increased structural stability gained by eliminating clay bound zeolite pellets that tend to fluidize and erode, and better thermal control during sorption to increase process efficiency. Test results that demonstrate such improvements are described and presented.

Howard, David F.↗
NASA NTRS2013

Temperature Trends in the Tropical Upper Troposphere and Lower Stratosphere: Connections with Sea Surface Temperatures and Implications for Water Vapor and Ozone

Satellite observations and chemistry-climate model experiments are used to understand the zonal structure of tropical lower stratospheric temperature, water vapor, and ozone trends. The warming in the tropical upper troposphere over the past 30 years is strongest near the Indo-Pacific warm pool, while the warming trend in the western and central Pacific is much weaker. In the lower stratosphere, these trends are reversed: the historical cooling trend is strongest over the Indo-Pacific warm pool and is weakest in the western and central Pacific. These zonal variations are stronger than the zonal-mean response in boreal winter. Targeted experiments with a chemistry-climate model are used to demonstrate that sea surface temperature (hereafter SST) trends are driving the zonal asymmetry in upper tropospheric and lower stratospheric tropical temperature trends. Warming SSTs in the Indian Ocean and in the warm pool region have led to enhanced moist heating in the upper troposphere, and in turn to a Gill-like response that extends into the lower stratosphere. The anomalous circulation has led to zonal structure in the ozone and water vapor trends near the tropopause, and subsequently to less water vapor entering the stratosphere. The radiative impact of these changes in trace gases is smaller than the direct impact of the moist heating. Projected future SSTs appear to drive a temperature and water vapor response whose zonal structure is similar to the historical response. In the lower stratosphere, the changes in water vapor and temperature due to projected future SSTs are of similar strength to, though slightly weaker than, that due directly to projected future CO2, ozone, and methane.

water vapor↗
NASA NTRS1988

Water intrusion in thin-skinned composite honeycomb sandwich structures

Thin-skinned composite honeycomb sandwich structures from the trailing edge of the U.S. Army's Apache and Chinook helicopters have been tested to ascertain their susceptibility to water intrusion as well as such intrusions' effects on impact damage and cyclic loading. Minimum-impact and fatigue conditions were determined which would create microcracks sufficiently large to allow the passage of water through the skins; damage sufficient for this to occur was for some skins undetectable under a 40X-magnification optical microscope. Flow rate was a function of moisture content, damage, applied strain, and pressure differences.

Jackson, Wade C.↗
NASA NTRS2011

Water Ice Clouds and Dust in the Martian Atmosphere Observed by Mars Climate Sounder

The water ice clouds are primarily controlled by the temperature structure and form at the water condensation level. Clouds in all regions presented show day/night differences. Cloud altitude varies between night and day in the SPH and tropics: (1) NPH water ice opacity is greater at night than day at some seasons (2) The diurnal thermal tide controls the daily variability. (3) Strong day/night changes indicate that the amount of gas in the atmosphere varies significantly. See significant mixtures of dust and ice at the same altitude planet-wide (1) Points to a complex radiative and thermal balance between dust heating (in the visible) and ice heating or cooling in the infrared. Aerosol layering: (1) Early seasons reveal a zonally banded spatial distribution (2) Some localized longitudinal structure of aerosol layers (3) Later seasons show no consistent large scale organization

Mars Climate Sounder (MCS) instrument↗
NASA NTRS1983

Airborne detection of oceanic turbidity cell structure using depth-resolved laser-induced water Raman backscatter

Airborne laser-induced, depth-resolved water Raman backscatter is useful in the detection and mapping of water optical transmission variations. This test, together with other field experiments, has identified the need for additional field experiments to resolve the degree of the contribution to the depth-resolved, Raman-backscattered signal waveform that is due to (1) sea surface height or elevation probability density; (2) off-nadir laser beam angle relative to the mean sea surface; and (3) the Gelbstoff fluorescence background, and the analytical techniques required to remove it. When converted to along-track profiles, the waveforms obtained reveal cells of a decreased Raman backscatter superimposed on an overall trend of monotonically decreasing water column optical transmission.

Hoge, F. E.↗
NASA NTRS2018

Water Walls Architecture: Massively Redundant And Highly Reliable Life Support For Long Duration Exploration Missions

The Water Wall concept proposes a system for structural elements that provide,thermal, radiation, water, solids and air treatment functions which are placed at the periphery of inflatable or rigid habitats. It also provides novel and potentially game changing mass reduction and reuse options for radiation protection. The approach would allow water recycling, air treatment, thermal control, and solids residuals treatment and recycling to be removed from the usable habitat volume, and placed in the walls by way of a radiation shielding water wall. It would also provide a mechanism to recover and reuse water treatment (solids) residuals to strengthen the habitat shell and a method of deriving radiation shielding from wastes generated on orbit. Water wall treatment elements would be a much-enlarged version of the commercially available hydration bags. Some water bags may have pervaporation membranes facing outward, which would provide the ability to remove H20, C02 and trace organics from the atmosphere and some would have hydrophobic internal membranes which would provide water, and waste recycling and some power generation.

Water Recycling↗
NASA NTRS1994

Redetermination of piperidinium hydrogen sulfide structure

The presence of adventitious water in a reaction between dicyclopentamethylene thiuram-disulfide (C5H10NCS2)(sub 2) and a picoline solution of tricyclopentadienyl indium(III) (C5H5)(sub 3). It resulted in the formation of piperidinium hydrogen sulfide (C5H13NS). The piperidinium hydrogen sulfide produced in this way was unambiguously characterized by X-ray crystallography. The structure determination showed that the piperidinium hydrogen sulfide crystal (MW = 119.23 g/mol) has an orthorhombic (Pbcm) unit cell whose parameters are: a = 9.818(2), b = 7.3720(1), c = 9.754(1) A, V = 706.0(3) A(exp 3), Z=4. D(sub chi) = 1.122 g cm(exp -3), Mo K(alpha) (lamda = 0.71073), mu= 3.36 cm(exp -1), F(000) = 264.0, T =293 K, R = 0.036 for 343 reflections with F(sub O)(sup 2) greater than 3 sigma (F(sub O)(sup 2)) and 65 variables. The compound consists of (C5H10NH2)(+) cations and (SH)(-) anions with both species residing on crystallographic mirror planes. N-H -- S hydrogen bonding contributes to the interconnection of neighboring piperidinium components of the compound.

Andras, Maria T.↗
NASA NTRS1989

The plume of the Yukon River in relation to the oceanography of the Bering Sea

The ecosystem of the northern Bering-Sea shelf was studied using data from the NOAA Very High Resolution Radiometer and AVHRR and the Landsat MSS and Thematic Mapper (TM) in conjunction with shipboard measurements. Emphasis was placed on the influence of the Yukon River on this inner shelf environment and on the evaluation of the utility of the new Landsat TM data for oceanography. It was found that the patterns of water mass distribution obtained from satellite images agreed reasonably well with the areal patterns of temperature, salinity, and phytoplankton distributions. The AVHRR, MSS, and TM data show that the Yukon-River discharge is warmer and more turbid than the surrounding coastal water that originates to the south; thus, the Yukon water contributes to the higher temperatures and lower transmissivity of the coastal water. The high resolution of the TM thermal IR band made it possible to observe complex patterns and structures in the surface water that could not be resolved on previous data sets.

Dean, Kenneson G.↗
NASA NTRS2000

Structural Characterization of Crystalline Ice Nanoclusters

Water ice nanoclusters are useful analogs for studying a variety of processes that occur within icy grains in the extraterrestrial environment. The surface of ice nanoclusters prepared in the laboratory is similar to the surface of interstellar ice grains. In cold molecular clouds, the silicate cores of interstellar grains are typically approx. 100 nm in diameter and have a coating of impure amorphous water ice. Depositional, thermal and radiolytic processes leave the surface and subsurface molecules in a disordered state. In this state, structural defects become mobile and reactions of trapped gases and small molecules can occur. The large surface area of nanocluster deposits relative to their bulk allows for routine observation of such surface-mediated processes. Furthermore, the disordered surface and subsurface layers in nanocluster deposits mimic the structure of amorphous ice rinds found on interstellar dust grains. Transmission Electron Microscopy (TEM has been used tn characterize the crystallinity, growth mechanism, and size distribution of nanoclusters formed from a mixture of water vapor with an inert carrier gas that has been rapidly cooled to 77K. E M imaging reveals a Gaussian size distribution around a modal diameter that increases from approx. 15 to 30 nm as the percentage of water vapor within the mixture increases from 0.5 to 2.007, respectively . TEM bright and dark field imaging also reveals the crystalline nature of the clusters. h4any of the clusters show a mosaic structure in which crystalline domains originate at the center Other images show mirror planes that are separated by approx. 10 nm. Electron diffraction patterns of these clusters show that the clusters are composed of cubic ice with only a small hexagonal component. Further, the crystalline domain size is approximately the same as the modal diameter suggesting that the clusters are single crystals.

Blake, David↗
NASA NTRS2012

NASA Advanced Explorations Systems: Concepts for Logistics to Living

The NASA Advanced Exploration Systems (AES) Logistics Reduction and Repurposing (LRR) project strives to enable a largely mission-independent cradle-to-grave-to-cradle approach to minimize logistics contributions to total mission architecture mass. The goals are to engineer logistics materials, common crew consumables, and container configurations to meet the following five basic goals: 1. Minimize intrinsic logistics mass and improve ground logistics flexibility. 2. Allow logistics components to be directly repurposed for on-orbit non-logistics functions (e.g., crew cabin outfitting) thereby indirectly reducing mass/volume. 3. Compact and process logistics that have not been directly repurposed to generate useful on-orbit components and/or compounds (e.g., radiation shielding, propellant, other usable chemical constituents). 4. Enable long-term stable storage and disposal of logistics end products that cannot be reused or repurposed (e.g., compaction for volume reduction, odor control, and maintenance of crew cabin hygienic conditions). 5. Allow vehicles in different mission phases to share logistics resources. This paper addresses the work being done to meet the second goal, the direct repurposing of logistics components to meet other on-orbit needs, through a strategy termed Logistics to Living (L2L). L2L has several areas but can be defined as repurposing or converting logistical items (bags, containers, foam, components, etc.) into useful crew items or life support augmentation on-orbit after they have provided their primary logistics function. The intent is that by repurposing items, dedicated crew items do not have to be launched and overall launch mass is decreased. For non-LEO missions, the vehicle interior volume will be relatively fixed so L2L will enable this volume to be used more effectively through reuse and rearrangement of logistical components. Past work in the area of L2L has already conceptually developed several potential technologies [Howe, Howard 2010]. Several of the L2L concepts that have shown the most potential in the past are based on NASA cargo transfer bags (CTBs) or their equivalents which are currently used to transfer cargo to and from the ISS. A high percentage of all logistics supplies are packaging mass and for a 6-month mission a crew of four might need over 100 CTBs. These CTBs are used for on-orbit transfer and storage but eventually becomes waste after use since down mass is very limited. The work being done in L2L also considering innovative interior habitat construction that integrate the CTBs into the walls of future habitats. The direct integration could provide multiple functions: launch packaging, stowage, radiation protection, water processing, life support augmentation, as well as structure. Reuse of these CTBs would reduce the amount of waste generated and also significantly reduce future up mass requirements for exploration missions. Also discussed here is the L2L water wall , an innovative reuse of an unfolded CTB as a passive water treatment system utilizing forward osmosis. The bags have been modified to have an inner membrane liner that allows them to purify wastewater. They may also provide a structural water-wall element that can be used to provide radiation protection and as a structural divider. Integration of the components into vehicle/habitat architecture and consideration of operations concepts and human factors will be discussed. In the future these bags could be designed to treat wastewater, concentrated brines, and solid wastes, and to dewater solid wastes and produce a bio-stabilized construction element. This paper will describe the follow-on work done in design, fabrication and demonstrations of various L2L concepts, including advanced CTBs for reuse/repurposing, internal outfitting studies and the CTB-based forward osmosis water wall.

Shull, Sarah A.↗
NASA NTRS2021

Characterization and Calibration of an AERONET-OC Radiometer

The Ocean Color component of the global Aerosol Robotic Network (AERONET-OC) utilizes CE-318 sun photometers modified for above-water radiometry from fixed structures such as oil rigs, lighthouses and service platforms. Primarily, AERONET-OC measurements allow determination of the water-leaving radiance required for the validation of ocean color satellite data products. In this study, we characterized and calibrated one instrument from the AERONET-OC network, identified as AERONET #080. A laser-illuminated integrating sphere of known radiance enabled determination of the absolute radiance responsivity for 7 bands. We compared the results to calibrations from the AERONET facility at the Goddard Space Flight Center of the National Aeronautics and Space Administration and from the Joint Research Centre of the European Commission. These results agree within the estimated mean comparison uncertainty of 1.88 % (k = 2). We also assessed these results using calibrated lamp-illuminated integrating spheres and observed a spectral dependence to the comparison results that is unexplained.

B. C. Johnson↗
NASA NTRS1997

The Role of Global Hydrologic Processes in Interannual and Long-Term Climate Variability

The earth's climate and its variability is linked inextricably with the presence of water on our planet. El Nino / Southern Oscillation-- the major mode of interannual variability-- is characterized by strong perturbations in oceanic evaporation, tropical rainfall, and radiation. On longer time scales, the major feedback mechanism in CO2-induced global warming is actually that due to increased water vapor holding capacity of the atmosphere. The global hydrologic cycle effects on climate are manifested through influence of cloud and water vapor on energy fluxes at the top of atmosphere and at the surface. Surface moisture anomalies retain the "memory" of past precipitation anomalies and subsequently alter the partitioning of latent and sensible heat fluxes at the surface. At the top of atmosphere, water vapor and cloud perturbations alter the net amount of radiation that the earth's climate system receives. These pervasive linkages between water, radiation, and surface processes present major complexities for observing and modeling climate variations. Major uncertainties in the observations include vertical structure of clouds and water vapor, surface energy balance, and transport of water and heat by wind fields. Modeling climate variability and change on a physical basis requires accurate by simplified submodels of radiation, cloud formation, radiative exchange, surface biophysics, and oceanic energy flux. In the past, we m safely say that being "data poor' has limited our depth of understanding and impeded model validation and improvement. Beginning with pre-EOS data sets, many of these barriers are being removed. EOS platforms with the suite of measurements dedicated to specific science questions are part of our most cost effective path to improved understanding and predictive capability. This talk will highlight some of the major questions confronting global hydrology and the prospects for significant progress afforded by EOS-era measurements.

Robertson, Franklin R.↗
NASA NTRS2007

Engineered Structured Sorbents for the Adsorption of Carbon Dioxide and Water Vapor from Manned Spacecraft Atmospheres: Applications and Modeling 2007/2008

In NASA s Vision for Space Exploration, humans will once again travel beyond the confines of earth s gravity, this time to remain there for extended periods. These forays will place unprecedented demands on launch systems. They must not only blast out of earth s gravity well as during the Apollo moon missions, but also launch the supplies needed to sustain a larger crew over much longer periods. Thus all spacecraft systems, including those for the separation of metabolic carbon dioxide and water from a crewed vehicle, must be minimized with respect to mass, power, and volume. Emphasis is also placed on system robustness both to minimize replacement parts and ensure crew safety when a quick return to earth is not possible. This paper describes efforts to improve on typical packed beds of sorbent pellets by making use of structured sorbents and alternate bed configurations to improve system efficiency and reliability. The development efforts described offer a complimentary approach combining testing of subscale systems and multiphysics computer simulations to characterize the regenerative heating substrates and evaluation of engineered structured sorbent geometries. Mass transfer, heat transfer, and fluid dynamics are included in the transient simulations.

Knox, James C.↗
NASA NTRS2010

Catalyst for Carbon Monoxide Oxidation

In many applications, it is highly desirable to operate a CO2 laser in a sealed condition, for in an open system the laser requires a continuous flow of laser gas to remove the dissociation products that occur in the discharge zone of the laser, in order to maintain a stable power output. This adds to the operating cost of the laser, and in airborne or space applications, it also adds to the weight penalty of the laser. In a sealed CO2 laser, a small amount of CO2 gas is decomposed in the electrical discharge zone into corresponding quantities of CO and O2. As the laser continues to operate, the concentration of CO2 decreases, while the concentrations of CO and O2 correspondingly increase. The increasing concentration of O2 reduces laser power, because O2 scavenges electrons in the electrical discharge, thereby causing arcing in the electric discharge and a loss of the energetic electrons required to boost CO2 molecules to lasing energy levels. As a result, laser power decreases rapidly. The primary object of this invention is to provide a catalyst that, by composition of matter alone, contains chemisorbed water within and upon its structure. Such bound moisture renders the catalyst highly active and very long-lived, such that only a small quantity of it needs to be used with a CO2 laser under ambient operating conditions. This object is achieved by a catalyst that consists essentially of about 1 to 40 percent by weight of one or more platinum group metals (Pt, Pd, Rh, Ir, Ru, Os, Pt being preferred); about 1 to 90 percent by weight of one or more oxides of reducible metals having multiple valence states (such as Sn, Ti, Mn, Cu, and Ce, with SnO2 being preferred); and about 1 to 90 percent by weight of a compound that can bind water to its structure (such as silica gel, calcium chloride, magnesium sulfate, hydrated alumina, and magnesium perchlorate, with silica gel being preferred). Especially beneficial results are obtained when platinum is present in the catalyst composition in an amount of about 5 to 25 (especially 7) percent by weight, SnO2 is present in an amount of about 30 to 40 (especially 40) percent by weight, and silica gel is present in an amount of 45 to 55 (especially 50) percent by weight. The composition of this catalyst was suggested by preliminary experiments in which a Pt/SnO2 catalyst was needed for bound water to enhance its activity. These experimental results suggested that if the water were bound to the surface, this water would enhance and prolong catalyst activity for long time periods. Because the catalyst is to be exposed to a laser gas mixture, and because a CO2 laser can tolerate only a very small amount of moisture, a hygroscopic support for the catalyst would provide the needed H2O into the gas. Silica gel is considered to be superior because of its property to chemisorb water on its surface over a wide range of moisture content.

Davis, Patricia↗