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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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All sourcesNASA NTRSDOE OSTI
NASA NTRS2009

PrimeSupplier Cross-Program Impact Analysis and Supplier Stability Indicator Simulation Model

PrimeSupplier, a supplier cross-program and element-impact simulation model, with supplier solvency indicator (SSI), has been developed so that the shuttle program can see early indicators of supplier and product line stability, while identifying the various elements and/or programs that have a particular supplier or product designed into the system. The model calculates two categories of benchmarks to determine the SSI, with one category focusing on agency programmatic data and the other focusing on a supplier's financial liquidity. PrimeSupplier was developed to help NASA smoothly transition design, manufacturing, and repair operations from the Shuttle program to the Constellation program, without disruption in the industrial supply base.

Calluzzi, Michael↗
NASA NTRS1993

Strategic planning for aircraft noise route impact analysis: A three dimensional approach

The strategic routing of aircraft through navigable and controlled airspace to minimize adverse noise impact over sensitive areas is critical in the proper management and planning of the U.S. based airport system. A major objective of this phase of research is to identify, inventory, characterize, and analyze the various environmental, land planning, and regulatory data bases, along with potential three dimensional software and hardware systems that can be potentially applied for an impact assessment of any existing or planned air route. There are eight data bases that have to be assembled and developed in order to develop three dimensional aircraft route impact methodology. These data bases which cover geographical information systems, sound metrics, land use, airspace operational control measures, federal regulations and advisories, census data, and environmental attributes have been examined and aggregated. A three dimensional format is necessary for planning, analyzing space and possible noise impact, and formulating potential resolutions. The need to develop this three dimensional approach is essential due to the finite capacity of airspace for managing and planning a route system, including airport facilities. It appears that these data bases can be integrated effectively into a strategic aircraft noise routing system which should be developed as soon as possible, as part of a proactive plan applied to our FAA controlled navigable airspace for the United States.

Bragdon, C. R.↗
NASA NTRS1993

Contact-impact analysis of deployable space systems

This paper presents simulation results of a flexible, deployable space system with multiple contact-impact events, using three different modeling approaches. In the first two approaches, the equations of motion of the system are written in terms of generalized coordinates of each component, with modal coordinates used to account for flexibility in the components. Two different methods are used to model contact-impact events in the systems. In the momentum balance method, as contact-impact occurs, momentum equations of the systems are solved for the jump discontinuity in velocity of generalized coordinates. Integration of the system is restarted with the new initial conditions from solutions of momentum equations. In the logical function method, a virtual spring connecting the two contact points is assumed. The virtual spring is active only when impact occurs. No special treatment is needed in the integration algorithm using this method. In the third approach, instead of using modal coordinates, a finite element based formulation for the transient dynamics of mechanical system is used to model flexibility of the components. The logical function method is used to model contact-impact in the third approach.

Wu, Shih-Chin↗
NASA NTRS2016

Using Tabulated Experimental Data to Drive an Orthotropic Elasto-Plastic Three-Dimensional Model for Impact Analysis

An orthotropic elasto-plastic-damage three-dimensional model with tabulated input has been developed to analyze the impact response of composite materials. The theory has been implemented as MAT 213 into a tailored version of LS-DYNA being developed under a joint effort of the FAA and NASA and has the following features: (a) the theory addresses any composite architecture that can be experimentally characterized as an orthotropic material and includes rate and temperature sensitivities, (b) the formulation is applicable for solid as well as shell element implementations and utilizes input data in a tabulated form directly from processed experimental data, (c) deformation and damage mechanics are both accounted for within the material model, (d) failure criteria are established that are functions of strain and damage parameters, and mesh size dependence is included, and (e) the theory can be efficiently implemented into a commercial code for both sequential and parallel executions. The salient features of the theory as implemented in LS-DYNA are illustrated using a widely used composite - the T800S/3900-2B[P2352W-19] BMS8-276 Rev-H-Unitape fiber/resin unidirectional composite. First, the experimental tests to characterize the deformation, damage and failure parameters in the material behavior are discussed. Second, the MAT213 input model and implementation details are presented with particular attention given to procedures that have been incorporated to ensure that the yield surfaces in the rate and temperature dependent plasticity model are convex. Finally, the paper concludes with a validation test designed to test the stability, accuracy and efficiency of the implemented model.

Polymer Matrix Composites↗
NASA NTRS2010

Modification of a Macromechanical Finite-Element Based Model for Impact Analysis of Triaxially-Braided Composites

A macro level finite element-based model has been developed to simulate the mechanical and impact response of triaxially-braided polymer matrix composites. In the analytical model, the triaxial braid architecture is simulated by using four parallel shell elements, each of which is modeled as a laminated composite. For the current analytical approach, each shell element is considered to be a smeared homogeneous material. The commercial transient dynamic finite element code LS-DYNA is used to conduct the simulations, and a continuum damage mechanics model internal to LS-DYNA is used as the material constitutive model. The constitutive model requires stiffness and strength properties of an equivalent unidirectional composite. Simplified micromechanics methods are used to determine the equivalent stiffness properties, and results from coupon level tests on the braided composite are utilized to back out the required strength properties. Simulations of quasi-static coupon tests of several representative braided composites are conducted to demonstrate the correlation of the model. Impact simulations of a represented braided composites are conducted to demonstrate the capability of the model to predict the penetration velocity and damage patterns obtained experimentally.

Goldberg, Robert K.↗
NASA NTRS2005

Environmental impact analysis with the airspace concept evaluation system

The National Aeronautics and Space Administration (NASA) Ames Research Center has developed the Airspace Concept Evaluation System (ACES), which is a fast-time simulation tool for evaluating Air Traffic Management (ATM) systems. This paper describes linking a capability to ACES which can analyze the environmental impact of proposed future ATM systems. This provides the ability to quickly evaluate metrics associated with environmental impacts of aviation for inclusion in multi-dimensional cost-benefit analysis of concepts for evolution of the National Airspace System (NAS) over the next several decades. The methodology used here may be summarized as follows: 1) Standard Federal Aviation Administration (FAA) noise and emissions-inventory models, the Noise Impact Routing System (NIRS) and the Emissions and Dispersion Modeling System (EDMS), respectively, are linked to ACES simulation outputs; 2) appropriate modifications are made to ACES outputs to incorporate all information needed by the environmental models (e.g., specific airframe and engine data); 3) noise and emissions calculations are performed for all traffic and airports in the study area for each of several scenarios, as simulated by ACES; and 4) impacts of future scenarios are compared to the current NAS baseline scenario. This paper also provides the results of initial end-to-end, proof-of-concept runs of the integrated ACES and environmental-modeling capability. These preliminary results demonstrate that if no growth is likely to be impeded by significant environmental impacts that could negatively affect communities throughout the nation.

Augustine, Stephen↗
NASA NTRS2007

Fire in the Brazilian Amazon: A Spatially Explicit Model for Policy Impact Analysis

This article implements a spatially explicit model to estimate the probability of forest and agricultural fires in the Brazilian Amazon. We innovate by using variables that reflect farmgate prices of beef and soy, and also provide a conceptual model of managed and unmanaged fires in order to simulate the impact of road paving, cattle exports, and conservation area designation on the occurrence of fire. Our analysis shows that fire is positively correlated with the price of beef and soy, and that the creation of new conservation units may offset the negative environmental impacts caused by the increasing number of fire events associated with early stages of frontier development.

Arima, Eugenio Y.↗
NASA NTRS2012

Exploration of COTS Ultrasonic NDE Methods for ISS MMOD Impact Analysis

The high orbital speed of the International Space Station (ISS) has created a concern about Micro-Meteorite and Orbital Debris (MMOD). The possibility exists that such an impact could cause significant damage to the ISS pressure wall, and possibly lead to a pressure leak. This paper explores the potential of using commercial off-the-shelf (COTS) Ultrasonic Non-Destructive Evaluation (NDE) techniques in order to inspect and analyze MMOD impact damage if such an event would happen to occur. Different types of intra vehicular activity (IVA) Ultrasonic NDE equipment were evaluated, including the Olympus Omniscan MX and the General Electric Phasor XS. The equipment was tested by inspecting various aluminum standards and impact damage test plates in order to determine technological limitations of the equipment as well as the ease of use and availability of features. This study allowed for the design of scanning procedures in order to evaluate the extent of damage caused by an MMOD impact. Lastly, comparisons were drawn between the different pieces of COTS software and a recommendation is made based on each device s capability.

Violette, Daniel P.↗
NASA NTRS2023

Developing a Hail and Wind Damage Swath Event Database from Daily MODIS True Color Imagery and Storm Reports for Impact Analysis and Applications

Hail and damaging winds are two threats associated with intense and severe thunderstorms that traverse the Midwest and Great Plains during the primary growing season. In certain severe thunderstorm events, large swaths of agricultural crops are impacted, allowing the damage to be viewed from multiple satellite remote sensing platforms. Previous studies have focused on analyzing individual hail and wind damage swaths (HWDSs) using satellite remote sensing, but these swaths have never been officially archived or documented. This lack of documentation has made it difficult to analyze the spatial extent and temporal frequency of HWDSs from year to year. This study utilizes daily true color imagery from MODIS aboard NASA’s Terra and Aqua satellites and daily local storm reports from the Storm Prediction Center to build a database of HWDSs occurring in the months of May through August, for years 2000 through 2020. This database identified 1,646 HWDSs in 12 states throughout the Midwest and Great Plains, confirmed through a combination of archived severe weather warnings, radar information, and official storm reports. For each entry in the HWDS database, a geospatial outline is provided along with the most likely date of first visible damage from MODIS imagery as well as the physical characteristics and time of occurrence estimated from available warnings. This study also provides a summary of the radar characteristics for a portion of the database. This database will further the understanding of severe weather damage by hail and wind to agriculture to help understand the frequency of these events and assist in mapping the impacted areas.

Climatology↗
NASA NTRS1975

The NASTRAN SRB slapdown water impact analysis

A computer analysis was made of the hydroelastic interaction between a shell structure representing the space shuttle solid rocket motor case and an incompressible fluid during the slapdown phase of water impact. The large motions and hydroelastic response of the system were obtained by numerical integration of the combined hydrodynamics and structural equations of motion and are analyzed for a selected interval after the initial nozzle impact. The computerization of the slapdown hydroelastic capability was incorporated into the general purpose NASTRAN computer code. The development of the theoretical basis, a guide to the program's usage, results of correlation and parameter studies, and a detailed description of the computer code are also included.

Herting, D. N.↗
NASA NTRS1988

Space Shuttle Orbiter windshield bird impact analysis

The NASA Space Shuttle Orbiter's windshield employs three glass panes separated by air gaps. The brittleness of the glass offers much less birdstrike energy-absorption capability than the laminated polycarbonate windshields of more conventional aircraft; attention must accordingly be given to the risk of catastrophic bird impact, and to methods of strike prevention that address bird populations around landing sites rather than the modification of the window's design. Bird populations' direct reduction, as well as careful scheduling of Orbiter landing times, are suggested as viable alternatives. The question of birdstrike-resistant glass windshield design for hypersonic aerospacecraft is discussed.

Edelstein, Karen S.↗
NASA NTRS1973

A land use and environmental impact analysis of the Norfolk-Portsmouth SMSA

The feasibility of using remote sensing techniques for land use and environmental assessment in the Norfolk-Portsmouth area is discussed. Data cover the use of high altitude aircraft and satellite remote sensing data for: (1) identifying various heirarchial levels of land use, (2) monitoring land use changes for repetitive basis, (3) assessing the impact of competing land uses, and (4) identifying areas of potential environmental deterioration. High altitude aircraft photographs (scale 1:120,000) acquired in 1959, 1970, and 1972, plus Earth Resources Technology Satellite (ERTS-1) color composite images acquired in 1972 were used for the land use and environmental assessments. The high altitude aircraft photography, as expected, was successfully used to map Level 1, Level 2, as well as some urban Level 3 land use categories. However, the detail of land use analysis obtainable from the ERTS imagery exceeded the expectations for the U.S. Geological Survey's land use classification scheme. Study results are consistent with the initial investigation which determined Level 1 land use change to be 16.7 square km per year.

Mitchel, W. B.↗
NASA NTRSDate not supplied

Noise Impact Analysis for Urban Air Mobility in Dallas-Fort Worth Metroplex

This study supports re-design of airspace and procedures for management of Urban Air Mobility (UAM) fleet operations in a given metropolitan area. A goal of UAM is to maintain geographic separation of UAM flight tracks from densely populated areas in order to reduce the potential negative community impact of UAM and manage flight trajectory in anticipation of allowable noise levels and current land use. A UAM route inventory and a demographic-data-optimized topographic map are developed for the Dallas-Fort Worth metroplex to identify routes or baseline route segments for reduction of noise impact. Noise contours are computed for baseline route and alternative route design given the desired UAM demand level. The impact of UAM fleet noise is predicted based on predicted number of people and noise-sensitive facilities located inside the noise contours.

Urban Air Mobility↗
NASA NTRSDate not supplied

Noise Impact Analysis for Urban Air Mobility in Dallas-Fort Worth Metroplex

This study supports re-design of airspace and procedures for management of Urban Air Mobility (UAM) fleet operations in a given metropolitan area. A goal of UAM is to maintain geographic separation of UAM flight tracks from densely populated areas in order to reduce the potential negative community impact of UAM and manage flight trajectory in anticipation of allowable noise levels and current land use. A UAM route inventory and a demographic-data-optimized topographic map are developed for the Dallas-Fort Worth metroplex to identify routes or baseline route segments for reduction of noise impact. Noise contours are computed for baseline route and alternative route design given the desired UAM demand level. The impact of UAM fleet noise is predicted based on predicted number of people and noise-sensitive facilities located inside the noise contours.

Urban Air Mobility↗
NASA NTRS2001

Adaptive Multi-Layer LMS Controller Design and Application to Active Vibration Suppression on a Truss and Proposed Impact Analysis Technique

This research develops an adaptive controller that actively suppresses a single frequency disturbance source at a remote position and tests the system on the NPS Space Truss. The experimental results are then compared to those predicted by an ANSYS finite element model. The NPS space truss is a 3.7-meter long truss that simulates a space-borne appendage with sensitive equipment mounted at its extremities. One of two installed piezoelectric actuators and an Adaptive Multi-Layer LMS control law were used to effectively eliminate an axial component of the vibrations induced by a linear proof mass actuator mounted at one end of the truss. Experimental and analytical results both demonstrate reductions to the level of system noise. Vibration reductions in excess of 50dB were obtained through experimentation and over 100dB using ANSYS, demonstrating the ability to model this system with a finite element model. This report also proposes a method to use distributed quartz accelerometers to evaluate the location, direction, and energy of impacts on the NPS space truss using the dSPACE data acquisition and processing system to capture the structural response and compare it to known reference Signals.

Barney, Timothy A.↗
NASA NTRS1973

DOD/NASA system impact analysis (study 2.1). Volume 1: Executive summary

Results are reported from a study made to determine engineering and cost analyses regarding the elements of space transportation systems. Specifically, a tug turnaround cost and abort modes and effects analyses were made. Study approach and objectives for both elements are given.

Source record↗