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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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System-assurance-analysis (SAA) methodology developed for aerospace launch-support systems proposed for nuclear powerplants. Study shows it is feasible and practical to apply SAA methodologyto nuclear powerplants. Essentially combination of analytical techniques related to safety and reliability with information system assisting managers in making decisions affecting safety and reliability.
In recent years, there has been renewed interest in Molten Salt Reactors (MSRs) for their potential advantages compared to reactors that rely on solid fuel. In response to such interest, many methods and codes have been developed to capture the unique features of MSRs. Among them, the System Analysis Module (SAM) is a modern system analysis tool that provides fast-running, modest-fidelity, whole-plant transient analysis capabilities, essential for fast-turnaround design scoping and engineering analyses of advanced reactor concepts. For liquid-fuel MSRs, the complex physics and chemistry involved in MSR operation—such as reactor kinetics, fluid flow, heat transfer, and salt composition dynamics—pose significant challenges for system-level modeling. Specific modeling capabilities are needed for system-level transient simulation. This paper presents recent advancements in SAM capability enhancements for system-level modeling of MSRs, focusing on improved simulation fidelity, computational efficiency, and multi-physics integration. Key enhancements include the development of species transport, Delayed Neutron Precursor (DNP) drift, modified Point Kinetics Equations (PKE), decay heat modeling, key fission product behavior, salt corrosion, and thermal-hydraulic coupling, as well as code robustness and performance enhancements for MSR applications. The code enhancement allows for better predictive accuracy in safety analysis, transient behavior, and operational optimization, thus supporting the design and licensing of next-generation MSRs. Results from case studies are presented to demonstrate the benefits of these enhancements in accurately capturing key reactor transient behaviors.
A contract with the Data Systems and Analysis Directorate contains a specified level of resources related to a specific set of work in support of three divisions within the Data Systems and Analysis Directorate. The divisions are Institutional Data Systems Division, Ground Data Systems Division, and Mission Planning and Analysis Division. The Statement of work defines at a functional requirements level the type of support to be provided to the three divisions. The contract provides for further technical direction to the contractor through issuance of Job Orders. The Job order is the prime method of further defining the work to be done, allocating a portion of the total resources in the contract to the defined tasks, and further delegating technical responsibility.
The Integrated Space Weather Analysis (iSWA) System is a comprehensive web-based platform for space weather information that combines data from solar, heliospheric and geospace observatories with forecasts based on the most advanced space weather models. The iSWA system collects, generates, and presents a wide array of space weather resources in an intuitive, user-configurable, and adaptable format - thus enabling users to respond to current and future space weather impacts as well as enabling post-impact analysis. iSWA currently provides over 200 data and modeling products, and features a variety of tools that allow the user to browse, combine, and examine data and models from various sources. This presentation will consist of a summary of the iSWA products and an overview of the customizable user interfaces, and will feature several tutorial demonstrations highlighting the interactive tools and advanced capabilities.
The project uses system engineering principles to address the need of Boy Scout leaders for an integrated system to facilitate advancement and awards records, leader training and planning for meetings and activities. Existing products to address needs of Scout leaders and relevant stakeholders function to support record keeping and some communication functions but opportunity exists for a better system to fully integrate these functions with training delivery and recording, activity planning along with feedback and information gathering from stakeholders. Key stakeholders for the sytem include Scouts and their families, leaders, training providers, sellers of supplies and awards, content generators and facilities that serve Scout activities. Key performance parameters for the system are protection of personal information, availability of current information, information accuracy and information content that has depth. Implementation concepts considered for the system include (1) owned and operated by Boy Scouts of America, (2) Contracted out to a vendor (3) distributed system that functions with BSA managed interfaces. The selected concept is to contract out to a vendor to maximize the likelihood of successful integration and take advantage of the best technology. Development of requirements considers three key use cases (1) System facilitates planning a hike with training needed satisfied in advance and advancement recording real time (2) Scheduling and documenting in-person training, (3) Family interested in Scouting receives information and can request follow-up. Non-functional requirements are analyzed with the Quality Function Deployment tool. Requirement addressing frequency of backup, compatibility with legacy and new technology, language support, software update are developed to address system reliability and intuitive interface. System functions analyzed include update of activity database, maintenance of advancement status, archive of documents, and monitoring of content that is accessible. The study examines risks associated with information security, technological change and continued popularity of Scouting. Mitigation is based on system functions that are defined. The approach to developing an improved system for facilitating Boy Scout leader functions was iterative with insights into capabilities coming in the course of working through the used cases and sequence diagrams.
For abstract, see N76-13141.
Efforts to integrate NASTRAN into a complete structural analysis system for use by large airframe design projects are discussed. NASTRAN was implemented as a major finite element structural analysis program to determine the static and dynamic behavior of complete airframes, as well as structural components. This requires modifications and additions to NASTRAN, to communicate with an existing system, and to provide facilities needed to work within the integrated structural analysis. For this purpose, several special DMAP modules were developed and introduced into the CALAC version of the NASTRAN system.
Methodology used in guidance system performance analysis /assessment/
The technical and cost analysis that was performed for the payload system operations analysis is presented. The technical analysis consists of the operations for the payload/shuttle and payload/tug, and the spacecraft analysis which includes sortie, automated, and large observatory type payloads. The cost analysis includes the costing tradeoffs of the various payload design concepts and traffic models. The overall objectives of this effort were to identify payload design and operational concepts for the shuttle which will result in low cost design, and to examine the low cost design concepts to identify applicable design guidelines. The operations analysis examined several past and current NASA and DoD satellite programs to establish a shuttle operations model. From this model the analysis examined the payload/shuttle flow and determined facility concepts necessary for effective payload/shuttle ground operations. The study of the payload/tug operations was an examination of the various flight timelines for missions requiring the tug.
ERGO, a human modeling software for ergonomic assessment and task analysis, was used for the crew systems interface analysis of the International Space Station (ISS) Propulsion Module (PM). The objective of analysis was to alleviate passageway size concerns. Three basic passageway configuration concepts: (1) 45" clear passageway without centerline offset (2) 50" clear passageway, 12" centerline offset, (3) 50" clear passageway, no centerline offset, and were reviewed. 95 percentile male and female models which were provided by the software performed crew system analysis from an anthropometric point of view. Four scenarios in which the crew floats in microgravity through a 50" no-offset passageway as they carry a 16" x 20" x 30" avionics box were simulated in the 10-weeks of intensive study. From the results of the analysis, concept (3) was the preferred option. A full scale, three-dimensional virtual model of the ISS Propulsion Module was created to experience the sense of the Intelligent Synthesis Environment and to evaluate the usability and applicability of the software.
Computer-oriented power systems analysis procedures in the electric utilities are surveyed. The growth of electric power systems is discussed along with the solution of sparse network equations, power flow, and stability studies.
NREL's advanced hosting capacity analysis and System Analysis Reports can help utilities, policymakers, and solar developers better understand the impact of adding new distributed photovoltaic (DPV) systems to the electrical distribution system. Advanced hosting capacity analysis considers the thresholds at which new DPV systems will trigger upgrades or changes to the electrical distribution system and evaluates the cost of different options for expanding the hosting capacity. It is one part of NREL's work to help stakeholders better understand the distribution system costs associated with integrating new DPV systems at different penetration levels. NREL's analysis uses a bottom-up methodology that involves simulating distribution systems. The analysis considers sequential increases in hosting capacity and corresponding upgrade costs from a baseline scenario with no DPV up to penetration levels greater than 100% of peak load.
Frequency selective surfaces (FSS's) are often used in spaceborne applications of reflector antennas due to their ability to allow multiple feeds to utilize the same reflector dish. The problems inherent in evaluating the FSS separately from the reflector system are discussed. A method of integrating the FSS effects into the reflector system analysis is presented. An example is given for the proposed Advanced Tracking and Delay Relay Satellite System (ATDRSS) single-access triband reflector antenna.
Abstract Power system dynamics are generally modeled by high dimensional non‐linear differential‐algebraic equations (DAEs) given a large number of components forming the network. These DAEs' complexity can grow exponentially due to the increasing penetration of distributed energy resources, whereas their computation time becomes sensitive due to the increasing interconnection of the power grid with other energy systems. This paper demonstrates the use of quantum computing algorithms to solve DAEs for power system dynamic analysis. We leverage a symbolic programming framework to equivalently convert the power system's DAEs into ordinary differential equations (ODEs) using index reduction methods and then encode their data into qubits using amplitude encoding. The system non‐linearity is captured by Hamiltonian simulation with truncated Taylor expansion so that state variables can be updated by a quantum linear equation solver. Our results show that quantum computing can solve the power system's DAEs accurately with a computational complexity polynomial in the logarithm of the system dimension. We also illustrate the use of recent advanced tools in scientific machine learning for implementing complex computing concepts, that is, Taylor expansion, DAEs/ODEs transformation, and quantum computing solver with abstract representation for power engineering applications.
Parameter analysis of dynamical systems by matrix approach, using n-dimensional parameter space
The Space Shuttle Program Communications and Tracking Systems Interface Analysis began April 18, 1983. During this time, the shuttle communication and tracking systems began flight testing. Two areas of analysis documented were a result of observations made during flight tests. These analyses involved the Ku-band communication system. First, there was a detailed analysis of the interface between the solar max data format and the Ku-band communication system including the TDRSS ground station. The second analysis involving the Ku-band communication system was an analysis of the frequency lock loop of the Gunn oscillator used to generate the transmit frequency. The stability of the frequency lock loop was investigated and changes to the design were reviewed to alleviate the potential loss of data due the loop losing lock and entering the reacquisition mode. Other areas of investigation were the S-band antenna analysis and RF coverage analysis.
Analysis of a robot control system leads to a broad range of processing requirements. One fundamental requirement of a robot control system is the necessity of a microcomputer system in order to provide sufficient processing capability.The use of multiple processors in a parallel architecture is beneficial for a number of reasons, including better cost performance, modular growth, increased reliability through replication, and flexibility for testing alternate control strategies via different partitioning. A survey of the progression from low level control synchronizing primitives to higher level communication tools is presented. The system communication and control mechanisms of existing robot control systems are compared to the hierarchical control model. The impact of this design methodology on the current robot control systems is explored.
Time division multiplexing system analysis for partial success