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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 1,405 records · Page 78
All sourcesNASA NTRSDOE OSTI
NASA NTRS1987

Apollo Lightcraft project

The detailed design of a beam-powered transatmospheric vehicle, the Apollo Lightcraft, was selected as the project for the design course. The principal goal is to reduce the LEO payload delivery cost by at least three orders of magnitude below the Space Shuttle Orbiter in the post 2020 era. The completely reusable, single-stage-to-orbit shuttlecraft will take off and land vertically, and have a reentry heat shield integrated with its lower surface. At appropriate points along the launch trajectory, the combined cycle propulsion system will transition through three or four airbreathing modes, and finally use a pure rocket mode for orbital insertion. The objective for the Spring semester propulsion source was to design and perform a detailed theoretical analysis on an advanced combined-cycle engine suitable for the Apollo Lightcraft. The preliminary theoretical analysis of this combined-cycle engine is now completed, and the acceleration performance along representative orbital trajectories was simulated. The total round trip cost is $3430 or $686 per person. This represents a payload delivery cost of $3.11/lb, which is a factor of 1000 below the STS. The Apollo Lightcraft concept is now ready for a more detailed investigation during the Fall semester Transatmosphere Vehicle Design course.

Myrabo, Leik N.↗
DOE OSTI2023

On unitarity of the Coon amplitude

The Coon amplitude is a one-parameter deformation of the Veneziano amplitude. We explore the unitarity of the Coon amplitude through its partial wave expansion using tools from q-calculus. Our analysis establishes manifest positivity on the leading and sub-leading Regge trajectories in arbitrary spacetime dimensions D, while revealing a violation of unitarity in a certain region of (q, D) parameter space starting at the sub-sub-leading Regge order. A combination of numerical studies and analytic arguments allows us to argue for the manifest positivity of the partial wave coefficients in fixed spin and Regge asymptotics.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
DOE OSTI2019

Lagrangian Evolution of the Northeast Pacific Marine Boundary Layer Structure and Cloud during CSET

Flight data from the Cloud System Evolution over the Trades (CSET) campaign over the Pacific stratocumulus-to-cumulus transition are organized into 18 Lagrangian cases suitable for study and future modeling, made possible by the use of a track-and-resample flight strategy. Analysis of these cases shows that 2-day Lagrangian coherence of long-lived species (CO and O 3 ) is high ($r$ = 0.93 and 0.73, respectively), but that of subcloud aerosol, MBL depth, and cloud properties is limited. Although they span a wide range in meteorological conditions, most sampled air masses show a clear transition when considering 2-day changes in cloudiness (−31% averaged over all cases), MBL depth (+560 m), estimated inversion strength (EIS; −2.2 K), and decoupling, agreeing with previous satellite studies and theory. Changes in precipitation and droplet number were less consistent. The aircraft-based analysis is augmented by geostationary satellite retrievals and reanalysis data along Lagrangian trajectories between aircraft sampling times, documenting the evolution of cloud fraction, cloud droplet number concentration, EIS, and MBL depth. An expanded trajectory set spanning the summer of 2015 is used to show that the CSET-sampled air masses were representative of the season, with respect to EIS and cloud fraction. Two Lagrangian case studies attractive for future modeling are presented with aircraft and satellite data. The first features a clear Sc–Cu transition involving MBL deepening and decoupling with decreasing cloud fraction, and the second undergoes a much slower cloud evolution despite a greater initial depth and decoupling state. Finally, potential causes for the differences in evolution are explored, including free-tropospheric humidity, subsidence, surface fluxes, and microphysics.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2023

Post-Shot Report for OMEGA Double Cylinders (CylDRT 22B)

The direct-drive double cylinder experimental platform is a high-energy-density (HED) science platform designed to image an imploding cylindrical target. The target consists of a directly-driven outer cylinder and a shock-and-collision driven inner cylinder. The purpose of this platform is to study hydrodynamic instability growth on the inner cylinder, the outer surface of which is classically Rayleigh-Taylor unstable during the acceleration phase. We present results from recent experiments at the OMEGA laser facility. These experiments were designed as a proof-of-principle for the platform, using the same cylinder exterior dimensions and direct-drive beam configuration as previous single cylinder experiments. In these experiments, three sets of targets were fielded: no machined perturbations (smooth), a sinusoidal mode-10 perturbation on the outer surface of the inner cylinder, and a mode-20 perturbation on the outer surface of the inner cylinder. The primary diagnostic was a gated x-ray framing camera which imaged the backlit inner cylinder on-axis for sixteen frames over a time window of 1 ns for each shot. A second side-lit radiograph captured one image per shot, diagnosing axial uniformity. In this report we include an overview of the results from both the backlighter and the sidelighter diagnostics. We discuss at length the experimental analysis process. Finally, we present the results of the smooth target implosion trajectory and compare them to post-shot simulations. We see favorable agreement between simulation and experiment.

70 PLASMA PHYSICS AND FUSION TECHNOLOGY↗
DOE OSTI2022

Adapting the Technology Performance Level Integrated Assessment Framework to Low-TRL Technologies Within the Carbon Capture, Utilization, and Storage Industry, Part I

With the urgent need to mitigate climate change and rising global temperatures, technological solutions that reduce atmospheric CO 2 are an increasingly important part of the global solution. As a result, the nascent carbon capture, utilization, and storage (CCUS) industry is rapidly growing with a plethora of new technologies in many different sectors. There is a need to holistically evaluate these new technologies in a standardized and consistent manner to determine which technologies will be the most successful and competitive in the global marketplace to achieve decarbonization targets. Life cycle assessment (LCA) and techno-economic assessment (TEA) have been employed as rigorous methodologies for quantitatively measuring a technology's environmental impacts and techno-economic performance, respectively. However, these metrics evaluate a technology's performance in only three dimensions and do not directly incorporate stakeholder needs and values. In addition, technology developers frequently encounter trade-offs during design that increase one metric at the expense of the other. The technology performance level (TPL) combined indicator provides a comprehensive and holistic assessment of an emerging technology's potential, which is described by its techno-economic performance, environmental impacts, social impacts, safety considerations, market/deployability opportunities, use integration impacts, and general risks. TPL incorporates TEA and LCA outputs and quantifies the trade-offs between them directly using stakeholder feedback and requirements. In this article, the TPL methodology is being adapted from the marine energy domain to the CCUS domain. Adapted metrics and definitions, a stakeholder analysis, and a detailed foundation-based application of the systems engineering approach to CCUS are presented. The TPL assessment framework is couched within the internationally standardized LCA framework to improve technical rigor and acceptance. It is demonstrated how stakeholder needs and values can be directly incorporated, how LCA and TEA metrics can be balanced, and how other dimensions (listed earlier) can be integrated into a single metric that measures a technology's potential.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗
NASA NTRS1973

Solar wind data from the MIT plasma experiments on Pioneer 6 and Pioneer 7

Hourly averages are presented of solar wind proton parameters obtained from experiments on the Pioneer 6 and Pioneer 7 spacecraft during the period December 16, 1965 to August 1971. The number of data points available on a given day depends upon the spacecraft-earth distance, the telemetry bit rate, and the ground tracking time allotted to each spacecraft. Thus, the data obtained earlier in the life of each spacecraft are more complete. The solar wind parameters are given in the form of plots and listings. Trajectory information is also given along with a detailed description of the analysis procedures used to extract plasma parameters from the measured data.

Lazarus, A. J.↗
NASA NTRS1976

Penetrator mission concepts for exploration of the Galilean satellites

Penetrators are elongated missile-shaped objects designed to implant scientific instrumentation to depths of 1 to 15 meters in a wide variety of soil. A typical penetrator weighs 35 kg and impacts the surface at 150 m/sec oriented as close as possible to vertical. A spacecraft bus carries the penetrators to the target body, controls their deployment, and serves as a data communications relay. The analysis addresses the question of basic feasibility and covers such topics as trajectory requirements and delivered mass capability, deployment modes and penetrator retro sizing, impact site accessibility, guidance and control, and penetrator/bus communications. We conclude that such missions, while difficult in many respects, appear to be technically feasible in the context of Jovian system exploration in the post-1985 time period.

Friedlander, A. L.↗
NASA NTRS1979

Lander flight path analysis

The primary functions of the Lander Flight Path Analysis Team (LFPAT) were to (1) design the Viking Lander (VL) descent trajectory and compute the descent guidance parameters for command transmission to the Viking Lander and Viking Orbiter (VO), (2) reconstruct the VL trajectory from separation to touchdown using data transmitted from the VL to Earth via the VO during descent, and (3) predict the VL/VO relay link system performance during descent and post touchdown. The preflight VL capability, the history of proposed descent trajectory designs as the site selection process evolved, and the final trajectory design and guidance parameters for each vehicle are addressed along with the trajectory reconstruction process, including the overall reconstructed VL flight path summary and a detailed discussion of the entry trajectory and atmosphere reconstruction results. The postland relay link prediction function is discussed.

Euler, E. A.↗
NASA NTRS1982

Preliminary sonic boom correlation of predicted and measured levels for STS-1 entry

A preliminary analysis correlating peaks from sonic boom pressure signatures recorded during the descent trajectory of the Orbiter Columbia, which landed in the dry lake bed at Edwards Air Force Base (EAFB), California, with measured wind tunnel signatures extrapolated from flight altitudes to the ground has been made for Mach numbers ranging from 1.3 to 6. The flight pressure signatures were recorded by microphones positioned at ground level near the groundtrack, whereas the wind tunnel signatures were measured during a test of a 0.0041-scale model Orbiter. The agreement between overpressure estimates based on wind tunnel data using preliminary flight trajectory data and oscillograph traces from ground measurements appears reasonable at this time for the range of Mach numbers considered. More detailed studies using final flight trajectory data and digitized ground measured data will be performed.

Garcia, F., Jr.↗
NASA NTRS1984

Post and a random-walk search mode

Multidisciplinary analysis often requires optimization of nonlinear systems that are subject to constraints. Trajectory optimization is one example of this situation. The Program to Optimize Simulated Trajectories (POST) was used successfully for a number of problems. The purpose is to describe POST and a new optimization approach that has been incorporated into it. Typical uses of POST will also be illustrated. The projected-gradient approach to optimization is the preferred option in POST and is discussed. A new approach to optimization, the random-walk approach, is described, and results with the random-walk approach are presented.

Martin, J. A.↗
NASA NTRS1989

Test and validation for robot arm control dynamics simulation

The Flight Telerobotic Servicer (FTS) program will require an ability to develop, in a cost effective manner, many simulation models for design, analysis, performance evaluation, and crew training. Computational speed and the degree of modeling fidelity associated with each simulation must be commensurate with problem objectives. To demonstrate evolving state-of-the-art general purpose multibody modeling capabilities, to validate these by laboratory testing, and to expose their modeling shortcomings, two focus problems at the opposite ends of the simulation spectrum are defined: (1) Coarse Acquisition Control Dynamics. Create a real time man-in-the-control-loop simulator. Provide animated graphical display of robot arm dynamics and tactile feedback sufficient for cueing the operator. Interface simulator software with human operated tactile feedback controller; i.e., the Kraft mini-master. (2) Fine, Precision Mode Control Dynamics. Create a high speed, high fidelity simulation model for the design, analysis, and performance evaluation of autonomous 7 degree-of-freedom (DOF) trajectory control algorithms. This model must contain detail dynamic models for all significant dynamics elements within the robot arm, such as joint drive mechanisms.

Yae, K. Harold↗
NASA NTRS1990

An unmanned probe to Pluto

Now that Voyager II has completed its grand tour of the solar system, all the planets in the solar system, with the exception of Pluto, have been studied. Even now, missions to return to Mercury, Venus, Mars Jupiter, and Saturn are currently flying or are planned. However, a mission to explore Pluto is not, at the present time, being considered seriously. The design problem presented to the students was very general, i.e., design an unmanned mission to Pluto with a launch window constraint of the years 2000 to 2010. All other characteristics of the mission, such as mission type (flyby, orbiter, lander, penetrator), scientific objectives and payload, and the propulsion system were to be determined by the design teams. The design studies exposed several general problems to be solved. Due to the extreme distance to Pluto (and a corresponding travel time in the range of 10 to 25 years), the spacecraft had to be lighter and more robust than current spacecraft designs. In addition, advanced propulsion concepts had to be considered. These included the new generation of launch vehicles and upper stages and nuclear electric propulsion. The probe design offered an abundance of synthesis and analysis problems. These included sizing trade studies, selection of subsystem components, analysis of spacecraft dynamics, stability and control, structural design and material selection, trajectory design, and selection of scientific equipment. Since the characteristics of the mission, excluding the launch window, were to be determined by the design teams, the solutions varied widely.

Source record↗
NASA NTRS1993

Mars 1994/1996: The French navigation tasks

In the fall of 1994, Russia will launch a spacecraft to Mars. France is involved in many scientific experiments which are onboard the spacecraft, as PI or CI. Some days before the Mars orbit insertion maneuver, two small stations and two penetrators will be injected into an entry trajectory. They will carry out for at least six months in situ analysis on the Martian surface. Two years later, a second spacecraft will be launched. It will carry the French balloon and a small rover. The scientific data of these landers will be relayed to earth via the spacecraft. However, during the first 20 days of their mission, Mars Observer will be used. To this end, a Mars balloon relay will be used, which will receive the data from the landers and store them into the memory of the Mars Observer camera. The spacecraft will also be used to localize the landers with the help of relative one-way Doppler measurements. An international cooperative is set up for this process, including JPS, Russian ballistic centers (Babakine, Institute of Applied Mathematics, Moscow Flight Control Center), and CNES Toulouse. Another task dedicated to the space mathematics division of CNES is to support the French scientists to prepare their telecommands and to analyze their telemetry. This second part is integrated into the French ground segment created for the Mars 94/96 mission. This paper describes the method used in CNES for the localization process, the support provided to the scientists, and the links for the data exchange.

Bonneau, Frederic↗
NASA NTRS1994

Ozone transport during a cut-off low event studied in the frame of the TOASTE program

A study of ozone transfer to the troposphere has been performed during two phases of the evolution of a cut-off low using both ozone vertical profiles and objective analysis of the ECMWF to compute potential vorticity distributions and air mass trajectories. Ozone profiles were measured by a ground based lidar system at the Observatoire de Haute Provence (OHP, 43 deg 55 N, 5 deg 42 E). A stratospheric ozone transport into the troposphere has been observed during a tropopause fold which occurred at the beginning of the cut-off low formation and during the erosion phase of the cut-off low. From the estimate of the maximum ozone content transferred to the troposphere, both mechanisms have the same order of magnitude of influence on the ozone flux to the troposphere. On a time scale of a few days, the correlation is very good between the potential vorticity and the ozone time evolution in the vicinity of the upper level frontal system.

Ancellet, G.↗
NASA NTRS1994

Warm core ring dynamics derived from satellite imagery

A reinterpretation of the life history of warm core ring 82-b is constructed from drifter trajectories, hydrographic profiles, and satellite-derived sea surface temperature fields. An analysis of the observations strongly suggests this ring is fundamentally a dipole structure for much of its existence. The dipole has unequal strength vortices, with the cyclone being the weaker component. Quantification of the dipole indicates the anticyclonic is oval shaped and rotates at approximately 7.7 deg per day, while the cyclone revolves around the anticyclone at about 14.5 deg per day, yielding an orbit period of approximately 25 days for the cyclone. The elusive part of the dipole explanation is in interpreting its surface signature as a function of time, as the cyclone appears to disappear when in proximity to the steep continental slope. Vortex modeling suggests that when the weaker cyclonic eddy is placed close to a boundary, the cyclone is drawn into a filament as it is advected through the gap between the anticyclone and the boundary. This means the cyclone is either in a filamentation state or undergoing the straining associated with filamentation approximately three fourths of this time, which is in complete agreement with the satellite imagery. In addition, the 82-B dipole configuration is sufficiently robust to survive continuous interaction with the continental slope and the onset of a Gulf Stream interaction. Although only warm core ring 82-B is analyzed in detail (and found to be a vortex pair), dipole configurations are found in the warm core ring 81-F time series as well.

Hooker, Stanford B.↗
NASA NTRS2004

Aerodynamic Characteristics and Glide-Back Performance of Langley Glide-Back Booster

NASA-Langley Research Center is conducting system level studies on an-house concept of a small launch vehicle to address NASA's needs for rapid deployment of small payloads to Low Earth Orbit. The vehicle concept is a three-stage system with a reusable first stage and expendable upper stages. The reusable first stage booster, which glides back to launch site after staging around Mach 3 is named the Langley Glide-Back Booster (LGBB). This paper discusses the aerodynamic characteristics of the LGBB from subsonic to supersonic speeds, development of the aerodynamic database and application of this database to evaluate the glide back performance of the LGBB. The aerodynamic database was assembled using a combination of wind tunnel test data and engineering level analysis. The glide back performance of the LGBB was evaluated using a trajectory optimization code and subject to constraints on angle of attack, dynamic pressure and normal acceleration.

Pamadi, Bandu N.↗
NASA NTRS2004

Assimilation of Stratospheric Meteorological and Constituent Observations: A Review

This talk reviews the assimilation of meteorological and constituent observations of the stratosphere. The first efforts to assimilate observations into stratospheric models were during the early 1980s, and a number of research studies followed during the next decade. Since the launch of the Upper Atmospheric Research Satellite (UARS) in 1991, model-assimilated data sets of the stratospheric meteorological state have been routinely available. These assimilated data sets were critical in bringing together observations from the different instruments on UARS as well as linking UARS observations to measurements from other platforms. Using trajectory-mapping techniques, meteorological assimilation analyses are, now, widely used in the analysis of constituent observations and have increased the level of quantitative study of stratospheric chemistry and transport. During the 1990s the use of winds and temperatures from assimilated data sets became standard for offline chemistry and transport modeling. variability in middle latitudes. The transport experiments, however, reveal a set of shortcomings that become obvious as systematic errors are integrated over time. Generally, the tropics are not well represented, mixing between the tropics and middle latitudes is overestimated, and the residual circulation is not accurate. These shortcomings reveal underlying fundamental challenges related to bias and noise. Current studies using model simulation and data assimilation in controlled experimentation are highlighting the issues that must be addressed if assimilated data sets are to be convincingly used to study interannual variability and decadal change. observations. The primary focus has been on stratospheric ozone, but there are efforts that investigate a suite of reactive chemical constituents. Recent progress in ozone assimilation shows the potential of assimilation to contribute to the validation of ozone observations and, ultimately, the retrieval of ozone profiles from space-based radiance measurements. Assimilated data sets provide accurate analyses of synoptic and planetary Scale At the same time, stratospheric assimilation is evolving to include constituent

Rood, Richard B.↗
NASA NTRS2007

Mission Analysis for the Don Quijote Phase-A Study

The Don Quijote Phase-A study is a definition study funded by ESA and devoted to the analysis of the possibilities to deflect a Near Earth Object (NEO) in the range of 300-800 m diameter. DEIMOS Space S.L. and EADS Astrium have teamed up within this study to form one of the three consortia that have analyzed these aspects for ESA. Target asteroids for the mission are 1989 ML, 2002 AT4 and Apophis. This paper presents the mission analysis activities within the consortium providing: low-thrust interplanetary rendezvous Orbiter trajectories to the target asteroids, ballistic interplanetary trajectories for the Impactor, Orbiter arrival description at the asteroids, Orbiter stable orbits characterization at the asteroid, deflection determination by means of a Radio Science Experiment (RSE) as well as the mission timelines and overall mission scenarios.

Cano, Juan L.↗