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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 1,297 records · Page 72
All sourcesNASA NTRSDOE OSTI
NASA NTRS2013

The Status of Spacecraft Bus and Platform Technology Development under the NASA In-Space Propulsion Technology Program

NASA's In-Space Propulsion Technology (ISPT) program has been developing technologies for lowering the cost of planetary science missions. The technology areas include electric propulsion technologies, spacecraft bus technologies, entry vehicle technologies, and design tools for systems analysis and mission trajectories. The electric propulsion technologies include critical components of both gridded and non-gridded ion propulsion systems. The spacecraft bus technologies under development include an ultra-lightweight tank (ULTT) and advanced xenon feed system (AXFS). The entry vehicle technologies include the development of a multi-mission entry vehicle, mission design tools and aerocapture. The design tools under development include system analysis tools and mission trajectory design tools.

Anderson, David↗
NASA NTRS2013

Products from NASA's In-Space Propulsion Program Applicable to Low-Cost Planetary Missions

NASAs In-Space Propulsion Technology (ISPT) program has been developing technologies for lowering the cost of planetary science missions. The technology areas include electric propulsion technologies, spacecraft bus technologies, entry vehicle technologies, and design tools for systems analysis and mission trajectories. The electric propulsion technologies include critical components of both gridded and non-gridded ion propulsion systems. The spacecraft bus technologies under development include an ultra-lightweight tank (ULTT) and advanced xenon feed system (AXFS). The entry vehicle technologies include the development of a multi-mission entry vehicle, mission design tools and aerocapture. The design tools under development include system analysis tools and mission trajectory design tools.

Anderson, David↗
NASA NTRSDate not supplied

Parametric Cost Modeling of a Mid-Lift-to-Drag Ratio Vehicle for Human Mars Entry, Descent, and Landing

Cost is one of the biggest obstacles to sending humans to Mars. However, spacecraft costs are typically estimated after the preliminary vehicle and mission concepts have been designed. By automating the cost estimation process, the effect of any change in vehicle or mission design on the mission cost can be determined more rapidly. This paper uses the tool SAPE-C (Systems Analysis for Planetary Entry, Descent, and Landing-Cost). SAPE-C integrates the cost modeling software SEER-H (System Estimation and Evaluation of Resources-Hardware) with a number of systems analysis tools and enables large design tradespace exploration early in the design process. SAPE-C is used to analyze several tradespaces of the Mid-Lift-to-Drag ratio rigid entry vehicle for human Mars missions. Key findings include quantifying the impacts of payload, vehicle length, and main engine specific impulse on the overall cost of the vehicle, and how the payload per lander and number of landers affects the cost of a campaign to Mars.

Mid L/D↗
NASA NTRSDate not supplied

Parametric Cost Modeling of a Mid-Lift-to-Drag Ratio Vehicle for Human Mars Entry, Descent, and Landing

Cost is one of the biggest obstacles to sending humans to Mars. However, spacecraft costs are typically estimated after the preliminary vehicle and mission concepts have been designed. By automating the cost estimation process, the effect of any change in vehicle or mission design on the mission cost can be determined more rapidly. This paper uses the tool SAPE-C (Systems Analysis for Planetary Entry, Descent, and Landing-Cost). SAPE-C integrates the cost modeling software SEER-H (System Estimation and Evaluation of Resources-Hardware) with a number of systems analysis tools and enables large design tradespace exploration early in the design process. SAPE-C is used to analyze several tradespaces of the Mid-Lift-to-Drag ratio rigid entry vehicle for human Mars missions. Key findings include quantifying the impacts of payload, vehicle length, and main engine specific impulse on the overall cost of the vehicle, and how the payload per lander and number of landers affects the cost of a campaign to Mars.

Paul D Friz↗
NASA NTRSDate not supplied

Parametric Cost Modeling of a Mid-Lift-to-Drag Ratio Vehicle for Human Mars Entry, Descent, and Landing

Cost is one of the biggest obstacles to sending humans to Mars. However, spacecraft costs are typically estimated after the preliminary vehicle and mission concepts have been designed. By automating the cost estimation process, the effect of any change in vehicle or mission design on the mission cost can be determined more rapidly. This paper uses the tool SAPE-C (Systems Analysis for Planetary Entry, Descent, and Landing-Cost). SAPE-C integrates the cost modeling software SEER-H (System Estimation and Evaluation of Resources-Hardware) with a number of systems analysis tools and enables large design tradespace exploration early in the design process. SAPE-C is used to analyze several tradespaces of the Mid-Lift-to-Drag ratio rigid entry vehicle for human Mars missions. Key findings include quantifying the impacts of payload, vehicle length, and main engine specific impulse on the overall cost of the vehicle, and how the payload per lander and number of landers affects the cost of a campaign to Mars.

Paul D Friz↗
NASA NTRS1971

Present-value analysis: A systems approach to public decisionmaking for cost effectiveness

Decision makers within Governmental agencies and Congress must evaluate competing (and sometimes conflicting) proposals which seek funding and implementation. Present value analysis can be an effective decision making tool by enabling the formal evaluation of the effects of competing proposals on efficient national resource utilization. A project's costs are not only its direct disbursements, but its social costs as well. How much does it cost to have those funds diverted from their use and economic benefit by the private sector to the public project? Comparisons of competing projects' social costs allow decision makers to expand their decision bases by quantifying the projects' impacts upon the economy and the efficient utilization of the country's limited national resources. A conceptual model is established for the choosing of the appropriate discount rate to be used in evaluation decisions through the technique.

Herbert, T. T.↗
NASA NTRS1995

Program For Analyzing Failures In A Complex System

Configurable Real-Time Analysis System (CRANS) computer program provides means for representing logically interconnected items (e.g., modules of equipment in complicated system) in matrix format. Capabilities provided helpful in real-time environment (e.g., operational environment of such system), in which need for quick evaluation of results of changes or failures. Program facilitates rapid logic-tree analysis. Written in C language.

Mccluney, R. Kevin↗
NASA NTRS1992

Comparison of current Shuttle and pre-Challenger flight suit reach capability during launch accelerations

The Challenger accident prompted the creation of a crew escape system which replaced the former Launch Entry Helmet (LEH) ensemble with the current Launch Entry Suit (LES). However, questions were raised regarding the impact of this change on crew reach capability. This study addressed the question of reach capability and its effects on realistic ground-based training for Space Shuttle missions. Eleven subjects performed reach sweeps in both the LEH and LES suits during 1 and 3 Gx acceleration trials in the Brooks AFB centrifuge. These reach sweeps were recorded on videotape and subsequently analyzed using a 3D motion analysis system. The ANOVA procedure of the Statistical Analysis System program was used to evaluate differences in forward and overhead reach. The results showed that the LES provided less reach capability than its predecessor, the LEH. This study also demonstrated that, since there was no substantial difference between 1 and 3 Gx reach sweeps in the LES, realistic Shuttle launch training may be accomplished in ground based simulators.

Bagian, James P.↗
NASA NTRSDate not supplied

The CLVTOPS Toolchain for NASA Space Launch System Liftoff Analysis and Post Flight Validation

This paper showcases the unique technical capabilities of the CLVTOPS multi-body flight dynamics toolchain developed by Marshall Space Flight Center (MSFC) for analyzing NASA’s Space Launch System (SLS) liftoff events. The CLVTOPS toolchain integrates high-fidelity simulations, geometric algorithms, advanced data analytics, and post-flight telemetry to demonstrate positive clearance between separating bodies and inform design decisions that enhance mission reliability. Proper liftoff separation is crucial to the success of the launch vehicle’s mission; vehicle impacts with the launch tower and supporting components incur a heightened risk of mission failure. For liftoff analysis, the CLVTOPS toolchain enables the integration of vehicle, launch pad, and environmental input models for the investigation of key clearance effectors. Furthermore, recent enhancements to the CLVTOPS toolchain allow for validation via photogrammetric trajectory reconstruction and plume pressure impingement estimation on the tower. The following sections will walk through the tool-chain, SLS liftoff ground rules and assumptions, key models, standard analysis, recent enhancements, and post-flight validation of the Artemis I mission liftoff event.

CLVTOPS↗
NASA NTRS1988

Dypas: A dynamic payload scheduler for shuttle missions

Decision and analysis systems have had broad and very practical application areas in the human decision making process. These software systems range from the help sections in simple accounting packages, to the more complex computer configuration programs. Dypas is a decision and analysis system that aids prelaunch shutlle scheduling, and has added functionality to aid the rescheduling done in flight. Dypas is written in Common Lisp on a Symbolics Lisp machine. Dypas differs from other scheduling programs in that it can draw its knowledge from different rule bases and apply them to different rule interpretation schemes. The system has been coded with Flavors, an object oriented extension to Common Lisp on the Symbolics hardware. This allows implementation of objects (experiments) to better match the problem definition, and allows a more coherent solution space to be developed. Dypas was originally developed to test a programmer's aptitude toward Common Lisp and the Symbolics software environment. Since then the system has grown into a large software effort with several programmers and researchers thrown into the effort. Dypas is currently using two expert systems and three inferencing procedures to generate a many object schedule. The paper will review the abilities of Dypas and comment on its functionality.

Davis, Stephen↗
NASA NTRS2008

Tool Support for Parametric Analysis of Large Software Simulation Systems

The analysis of large and complex parameterized software systems, e.g., systems simulation in aerospace, is very complicated and time-consuming due to the large parameter space, and the complex, highly coupled nonlinear nature of the different system components. Thus, such systems are generally validated only in regions local to anticipated operating points rather than through characterization of the entire feasible operational envelope of the system. We have addressed the factors deterring such an analysis with a tool to support envelope assessment: we utilize a combination of advanced Monte Carlo generation with n-factor combinatorial parameter variations to limit the number of cases, but still explore important interactions in the parameter space in a systematic fashion. Additional test-cases, automatically generated from models (e.g., UML, Simulink, Stateflow) improve the coverage. The distributed test runs of the software system produce vast amounts of data, making manual analysis impossible. Our tool automatically analyzes the generated data through a combination of unsupervised Bayesian clustering techniques (AutoBayes) and supervised learning of critical parameter ranges using the treatment learner TAR3. The tool has been developed around the Trick simulation environment, which is widely used within NASA. We will present this tool with a GN&C (Guidance, Navigation and Control) simulation of a small satellite system.

Schumann, Johann↗
DOE OSTI2020

A Microbe Associated with Sleep Revealed by a Novel Systems Genetic Analysis of the Microbiome in Collaborative Cross Mice

The microbiome influences health and disease through complex networks of host genetics, genomics, microbes, and environment. Identifying the mechanisms of these interactions has remained challenging. Systems genetics in laboratory mice (Mus musculus) enables data-driven discovery of biological network components and mechanisms of host–microbial interactions underlying disease phenotypes. To examine the interplay among the whole host genome, transcriptome, and microbiome, we mapped QTL and correlated the abundance of cecal messenger RNA, luminal microflora, physiology, and behavior in a highly diverse Collaborative Cross breeding population. One such relationship, regulated by a variant on chromosome 7, was the association of Odoribacter (Bacteroidales) abundance and sleep phenotypes. In a test of this association in the BKS.Cg-Dock7 m +/+ Lepr db /J mouse model of obesity and diabetes, known to have abnormal sleep and colonization by Odoribacter, treatment with antibiotics altered sleep in a genotype-dependent fashion. The many other relationships extracted from this study can be used to interrogate other diseases, microbes, and mechanisms.

59 BASIC BIOLOGICAL SCIENCES↗
NASA NTRS1988

Use of an expert system data analysis manager for space shuttle main engine test evaluation

The ability to articulate, collect, and automate the application of the expertise needed for the analysis of space shuttle main engine (SSME) test data would be of great benefit to NASA liquid rocket engine experts. This paper describes a project whose goal is to build a rule-based expert system which incorporates such expertise. Experiential expertise, collected directly from the experts currently involved in SSME data analysis, is used to build a rule base to identify engine anomalies similar to those analyzed previously. Additionally, an alternate method of expertise capture is being explored. This method would generate rules inductively based on calculations made using a theoretical model of the SSME's operation. The latter rules would be capable of diagnosing anomalies which may not have appeared before, but whose effects can be predicted by the theoretical model.

Abernethy, Ken↗
NASA NTRS1981

APPLEPIPS /Apple Personal Image Processing System/ - An interactive digital image processing system for the Apple II microcomputer

Recent developments related to microprocessor-based personal computers have made low-cost digital image processing systems a reality. Image analysis systems built around these microcomputers provide color image displays for images as large as 256 by 240 pixels in sixteen colors. Descriptive statistics can be computed for portions of an image, and supervised image classification can be obtained. The systems support Basic, Fortran, Pascal, and assembler language. A description is provided of a system which is representative of the new microprocessor-based image processing systems currently on the market. While small systems may never be truly independent of larger mainframes, because they lack 9-track tape drives, the independent processing power of the microcomputers will help alleviate some of the turn-around time problems associated with image analysis and display on the larger multiuser systems.

Masuoka, E.↗
DOE OSTI2022

3013 Inner Container Closure Weld Region (ICCWR) Characterization by Wide Area 3D Measurement System (WAMS) Analysis (FY21 Progress Report)

As part of the 3013 Surveillance Program, through-wall penetration from stress corrosion cracking (SCC) of the 3013 inner containers has been identified as the most credible condition for failure withing the 50- years lifetime. Chlorides contained in Pu-bearing material, together with intra-canister humidity levels, metallurgical conditions, and internal stresses have been found to produce corrosion in the Inner Container Closure Weld Region (ICCWR) of the 3013 canister system. A Laser Confocal Microscope (LCM) is used as part of the 3013 Surveillance Program protocol to identify the prevalence of corrosion and corrosionrelated cracking in the ICCWR2. With the LCM, a close visual examination is made of the ICCWR surface along with measurements of corrosion-related features. LCM inspections produce immense amounts of image data that is time intensive to analyze. There is also a 9-year backlog of images, with approximately 49 canisters that must be evaluated. To expedite data analysis and reduce the amount of generated data, a Wide Area 3D Measurement System (WAMS) microscope has been added to the examination protocol. Although WAMS is a lower resolution microscope, small features of interest can be still identified. The advantage of collecting data for the full circumference using the WAMS is that it can take about 1/16 of the time needed with the LCM. Both systems offer capabilities that combined can be utilized to expedite the examination of the ICCWR. The WAMS is an efficient system for screening and identification of corrosion features while the LCM can be utilized to obtain higher resolution images areas identified by the WAMS. This report explains and justifies the data collection methods used with the WAMS. It includes a summary of the data generated by WAMS in FY21. The goals set for data collection in FY21 were met. A total of twenty-two DE’s were imaged, and analysis was carried out on eleven samples. The analyzed samples showed large numbers of potential cracks and pits distributed throughout the surfaces. Lastly, to explain the advantages of the WAMS, its capabilities were compared to those of a simpler microscope. Micrographs of the samples imaged in FY21 and those analyzed are included in the appendices.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
NASA NTRS1970

Guidance, navigation, and control systems performance analysis: Apollo 13 mission report

The conclusions of the analyses of the inflight performance of the Apollo 13 spacecraft guidance, navigation, and control equipment are presented. The subjects discussed are: (1) the command module systems, (2) the lunar module inertial measurement unit, (3) the lunar module digital autopilot, (4) the lunar module abort guidance system, (5) lunar module optical alignment checks, and (6) spacecraft component separation procedures.

Source record↗
NASA NTRSDate not supplied

Cruise Propulsion System Thermal Analysis for NASA’s X-57 “Maxwell” Mod II Configuration

The X-57 “Maxwell” is NASA’s flight demonstrator for distributed electric propulsion technologies. The X-57 Mod II configuration is designed to test the electric cruise propulsion system for X-57 and features an electric cruise motor mounted in an integral nacelle on each wing. The electric motors and associated control equipment for X-57 Mod II are air-cooled; therefore, they require adequate cooling airflow to stay within temperature limits set by the X-57 project in all relevant flight conditions. A computational flow analysis was conducted to estimate the internal flow properties of the X-57 Mod II cruise nacelles in three critical flight conditions. These flow properties were then used to determine the boundary conditions for individual component thermal models, which were used to estimate individual component operating temperatures. The results indicated that the low-speed, low-altitude initial takeoff climb during hot day conditions was the sizing condition from a cooling perspective. The analysis found that the cooling flowpaths in the X-57 Mod II cruise nacelles are adequate to provide cooling to most of the components with the appropriate amount of thermal margin. The two components that are not anticipated to have the appropriate margin can be accommodated with a small (< 2°C) adjustment to the project operating limitations.

Nicholas K. Borer↗
DOE OSTI2022

SAM-ML: Integrating data-driven closure with nuclear system code SAM for improved modeling capability

Advanced reactors often involve complicated thermal-fluid (T-F) phenomena. Modeling such phenomena with the traditional one-dimensional (1-D) system code is a challenging task. The System Analysis Module (SAM), a modern nuclear system code, has developed a coarse mesh multi-dimensional (multi-D) flow model to capture the spatial effect of T-F phenomena in advanced reactors. As a coarse mesh solver, constitutive relations are required for SAM's multi-D model for unresolved fine-scale physics, such as turbulence. Here this work presents a novel approach that integrates neural networks as data-driven closure for SAM's multi-D flow model. The data-driven closure is trained with fine-resolution data to ensure its accuracy while maintaining a coarse mesh setup to ensure its efficiency and consistency with SAM. We demonstrate the applicability of this SAM-ML capability in an open volume thermal stratification problem, where a neural network model serves as the eddy viscosity closure. A customized interface between the neural network and SAM is developed to ensure flexible and efficient data exchange. The SAM-ML results demonstrate superior performance compared to SAM's built-in zero-equation eddy viscosity closure. The case study shows that although the generalization capability of the data-driven closure still needs to be improved for different transient case or different geometric setup, SAM -ML demonstrates good potential for challenging simulation problems with improved accuracy and computational efficiency.

22 GENERAL STUDIES OF NUCLEAR REACTORS↗