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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 1,171 records · Page 65
All sourcesNASA NTRSDOE OSTI
NASA NTRS2002

Proceeding With Caution

E-ViEWS was developed with assistance from the Technology Affiliates Program at NASA's Jet Propulsion Laboratory (JPL). The system incorporates JPL expertise in the areas of systems engineering, transportation systems, antennas, controls, optical displays, and mechanical systems. It consists of three modules that streamline traffic flow in the presence of emergency vehicles, and act as a guardrail to protect today's motorists from distractions that could result in serious accidents. Although emergency vehicles use sirens and flashing lights to warn others as they rapidly pass through intersections, some drivers may be oblivious to the emergency situation at hand, due to factors such as car radios, cellular phones, air conditioning, rolled-up windows, vehicle sound proofing, and hearing impairment. The company has also the company has launched testing efforts for Intellirail, a highly intelligent locomotive warning system that is based on the JPL/E-ViEWS preemption emergency vehicle platform.

Source record↗
NASA NTRS2003

Comparison of Mars Aircraft Propulsion Systems

The propulsion system is a critical aspect of the performance and feasibility of a Mars aircraft. Propulsion system mass and performance greatly influence the aircraft s design and mission capabilities. Various propulsion systems were analyzed to estimate the system mass necessary for producing 35N of thrust within the Mars environment. Three main categories of propulsion systems were considered: electric systems, combustion engine systems and rocket systems. Also, the system masses were compared for mission durations of 1, 2, and 4 h.

Colozza, Anthony J.↗
NASA NTRS2011

Coupling Between Waveguide-Fed Slot Arrays

Coupling between two waveguide-fed planar slot arrays has been investigated using full-wave analysis. The analysis employs the method-of-moments solution to the pertinent coupled integral equations for the aperture electric field of all slots. In order to compute coupling between two arrays, the input port of the first array is excited with a TE(sub 10) mode wave while the second one is match-terminated. After solving the moment method matrix equations, the aperture fields of all slots are obtained and thereby the TE(sub 10) mode wave received at the input port of the second array is determined. Coupling between two arrays is the ratio of the wave amplitude arriving in the second array port to the incident wave amplitude at the first array port. The coupling mechanism has been studied as a function of spacing between arrays in different directions, e.g. the electric field plane, the magnetic field plane, and the diagonal plane. Computed coupling values are presented for different array geometries. This work is novel since it provides a good understanding of coupling between waveguide-fed slot arrays as a function of spacing and orientation for different aperture distributions and array architectures. This serves as a useful tool for antenna design engineers and system engineers.

Rengarajan, Sembiam↗
NASA NTRS2012

Assessment of NASA's Aircraft Noise Prediction Capability

A goal of NASA s Fundamental Aeronautics Program is the improvement of aircraft noise prediction. This document provides an assessment, conducted from 2006 to 2009, on the current state of the art for aircraft noise prediction by carefully analyzing the results from prediction tools and from the experimental databases to determine errors and uncertainties and compare results to validate the predictions. The error analysis is included for both the predictions and the experimental data and helps identify where improvements are required. This study is restricted to prediction methods and databases developed or sponsored by NASA, although in many cases they represent the current state of the art for industry. The present document begins with an introduction giving a general background for and a discussion on the process of this assessment followed by eight chapters covering topics at both the system and the component levels. The topic areas, each with multiple contributors, are aircraft system noise, engine system noise, airframe noise, fan noise, liner physics, duct acoustics, jet noise, and propulsion airframe aeroacoustics.

Dahl, Milo D.↗
NASA NTRSDate not supplied

NASA Glenn Engine Control Research Facilities

This document describes NASA Glenn facilities available for performing propulsion control work. This includes a real-time hardware in the loop facility for performing complex, multi-rate simulations. The second facility describes a small engine test stand with a modifiable controller for performing advanced control studies and/or testing engine system modifications.

Control Systems↗
DOE OSTI2022

Tabulated Fluid Properties Research Report

The Multiphysics Object-Oriented Simulation Environment (MOOSE) enables a wide range of advanced nuclear reactor simulations.[6] Under the guidance of MOOSE’s Thermal Hydraulics Team,I worked to expand the capabilities of Tabulated Fluid Properties (TFP) in the fluid properties module. The fluid properties module allows the user to determine a variety of fluid properties by interpolating points between tabulated data. I implemented the ability to use bilinear interpolation instead of bicubic interpolation for interpolating tabulated data. I also changed the method of variable set inversions to use a 2-dimensional Newton’s Method utility that I created. Variable set inversions are often done from (v,e) to (p,T), where v is specific volume, e is specific internal energy, p is pressure and T is temperature. New routines have also been added into TFP such that it can be used with more applications, such as the Navier Stokes and Thermal Hydraulics modules in MOOSE for Pronghorn[5] and RELAP-7[1] respectively. This work was spurred by interest from NASA in testing a Nuclear Thermal Propulsion (NTP) engine system. NTP engines have drastically different fluid properties throughout the engine and Tabulated Fluid Properties provides the flexibility needed to properly simulate and test these engines.

22 GENERAL STUDIES OF NUCLEAR REACTORS↗
DOE OSTI2024

How to Build a Quantum Supercomputer: Scaling from Hundreds to Millions of Qubits

In the span of four decades, quantum computation has evolved from an intellectual curiosity to a potentially realizable technology. Today, small-scale demonstrations have become possible for quantum algorithmic primitives on hundreds of physical qubits and proof-of-principle error-correction on a single logical qubit. Nevertheless, despite significant progress and excitement, the path toward a full-stack scalable technology is largely unknown. There are significant outstanding quantum hardware, fabrication, software architecture, and algorithmic challenges that are either unresolved or overlooked. These issues could seriously undermine the arrival of utility-scale quantum computers for the foreseeable future. Here, we provide a comprehensive review of these scaling challenges. We show how the road to scaling could be paved by adopting existing semiconductor technology to build much higher-quality qubits, employing system engineering approaches, and performing distributed quantum computation within heterogeneous high-performance computing infrastructures. These opportunities for research and development could unlock certain promising applications, in particular, efficient quantum simulation/learning of quantum data generated by natural or engineered quantum systems. To estimate the true cost of such promises, we provide a detailed resource and sensitivity analysis for classically hard quantum chemistry calculations on surface-code error-corrected quantum computers given current, target, and desired hardware specifications based on superconducting qubits, accounting for a realistic distribution of errors. Furthermore, we argue that, to tackle industry-scale classical optimization and machine learning problems in a cost-effective manner, heterogeneous quantum-probabilistic computing with custom-designed accelerators should be considered as a complementary path toward scalability.

Mohseni, Masoud↗
DOE OSTI2021

Incorporating the Role(s) of Human Actors in Complex System Design for Safety and Security

Traditional systems engineering demonstrates the importance of customer needs in scoping and defining design requirements; yet, in practice, other human stakeholders are often absent from early lifecycle phases. Human factors are often omitted in practice when evaluating and down-selecting design options due to constraints such as time, money, access to user populations, or difficulty in proving system robustness through the inclusion of human behaviors. Advances in systems engineering increasingly include non-technical influences into the design, deployment, operations, and maintenance of interacting components to achieve common performance objectives. Furthermore, such advances highlight the need to better account for the various roles of human actors to achieve desired performance outcomes in complex systems. Many of these efforts seek to infuse lessons and concepts from human factors (enhanced decision-making through Crew Resource Management), systems safety (Rasmussen's “drift toward danger”) and organization science (Giddens' recurrent human acts leading to emergent behaviors) into systems engineering to better understand how socio-technical interactions impact emergent system performance. Safety and security are examples of complex system performance outcomes that are directly impacted by varying roles of human actors. Using security performance of high consequence facilities as a representative use case, this article will outline the System Context Lenses to understand how to include various roles of human actors into systems engineering design. Several exemplar applications of this organizing lenses will be summarized and used to highlight more generalized insights for the broader systems engineering community.

42 ENGINEERING↗
NASA NTRS2006

State Analysis Database Tool

The State Analysis Database Tool software establishes a productive environment for collaboration among software and system engineers engaged in the development of complex interacting systems. The tool embodies State Analysis, a model-based system engineering methodology founded on a state-based control architecture (see figure). A state represents a momentary condition of an evolving system, and a model may describe how a state evolves and is affected by other states. The State Analysis methodology is a process for capturing system and software requirements in the form of explicit models and states, and defining goal-based operational plans consistent with the models. Requirements, models, and operational concerns have traditionally been documented in a variety of system engineering artifacts that address different aspects of a mission s lifecycle. In State Analysis, requirements, models, and operations information are State Analysis artifacts that are consistent and stored in a State Analysis Database. The tool includes a back-end database, a multi-platform front-end client, and Web-based administrative functions. The tool is structured to prompt an engineer to follow the State Analysis methodology, to encourage state discovery and model description, and to make software requirements and operations plans consistent with model descriptions.

Rasmussen, Robert↗
NASA NTRS2007

The Nation's Vision for Exploration: An Update

I.Current key activities: a) Constellation Level2-System Engineering. b) Lunar Architecture Team (LAT)2-technology assessment and architectural option for the lander. c) Mars Architecture Team-system engineering support, Science integration, precursor program planning. d) Lunar Lander Project Core Team-GN&C and Flight system engineering. e) Technology program-supporting multiple projects in robotics, power systems, aero entry technology. f) Mission Operation Project-Mission operations system engineering. g) Advanced Environmental Monitoring Instruments. H. Lunar Reconnaissance Orbiter instrument (Diviner). II. Mission Proposals a) Lunar Sample return. b) Lunar Gravity field mapper.

space exploration↗
NASA NTRS2017

The 2015-2016 SEPMAP Program at NASA JSC: Science, Engineering, and Program Management Training

The Systems Engineering Project Management Advancement Program (SEPMAP) at NASA Johnson Space Center (JSC) is an employee development program designed to provide graduate level training in project management and systems engineering. The program includes an applied learning project with engineering and integrated science goals requirements. The teams were presented with a task: Collect a representative sample set from a field site using a hexacopter platform, as if performing a scientific reconnaissance to assess whether the site is of sufficient scientific interest to justify exploration by astronauts. Four teams worked through the eighteen-month course to design customized sampling payloads integrated with the hexacopter, and then operate the aircraft to meet sampling requirements of number (≥ 5) and mass (≥ 5g each). The "Mars Yard" at JSC was utilized for this purpose. This project activity closely parallels NASA plans for the future exploration of Mars, where remote sites will be reconnoitered ahead of crewed exploration.

Graham, L.↗
NASA NTRS2005

Introduction to System Health Engineering and Management in Aerospace

This paper provides a technical overview of Integrated System Health Engineering and Management (ISHEM). We define ISHEM as "the paper provides a techniques, and technologies used to design, analyze, build, verify, and operate a system to prevent faults and/or minimize their effects." This includes design and manufacturing techniques as well operational and managerial methods. ISHEM is not a "purely technical issue" as it also involves and must account for organizational, communicative, and cognitive f&ms of humans as social beings and as individuals. Thus the paper will discuss in more detail why all of these elements, h m the technical to the cognitive and social, are necessary to build dependable human-machine systems. The paper outlines a functional homework and architecture for ISHEM operations, describes the processes needed to implement ISHEM in the system life-cycle, and provides a theoretical framework to understand the relationship between the different aspects of the discipline. It then derives from these and the social and cognitive bases a set of design and operational principles for ISHEM.

Johnson, Stephen B.↗
NASA NTRS1995

Computational Simulation Of A Nuclear Engine

Nuclear Engine System Simulation (NESS) computer program developed to satisfy need for accurate, stand-alone software tool for preliminary design analysis of nuclear thermal propulsion (NTP) engine system. Used for rapid, preliminary detailed design analysis of both reactor and key engine systems. Principal outputs include operating characteristics and weights of reactors, engine-system parameters as performances, weights, dimensions, pressures, temperatures, and mass flows, and operating characteristics of turbopumps under both design and off-design operating conditions. Written in FORTRAN 77.

Walton, J. T.↗
NASA NTRS2011

Lessons Learned from the Space Shuttle Engine Cutoff System (ECO) Anomalies

The Space Shuttle Orbiter's main engine cutoff (ECO) system first failed ground checkout in April, 2005 during a first tanking test prior to Return-to-Flight. Despite significant troubleshooting and investigative efforts that followed, the root cause could not be found and intermittent anomalies continued to plague the Program. By implementing hardware upgrades, enhancing monitoring capability, and relaxing the launch rules, the Shuttle fleet was allowed to continue flying in spite of these unexplained failures. Root cause was finally determined following the launch attempts of STS-122 in December, 2007 when the anomalies repeated, which allowed drag-on instrumentation to pinpoint the fault (the ET feedthrough connector). The suspect hardware was removed and provided additional evidence towards root cause determination. Corrective action was implemented and the system has performed successfully since then. This white paper presents the lessons learned from the entire experience, beginning with the anomalies since Return-to-Flight through discovery and correction of the problem. To put these lessons in better perspective for the reader, an overview of the ECO system is presented first. Next, a chronological account of the failures and associated investigation activities is discussed. Root cause and corrective action are summarized, followed by the lessons learned.

Martinez, Hugo E.↗
NASA NTRS2018

Spaceport Command and Control System: Network Engineering

The Spaceport Command and Control System (SCCS) project's goal is to facilitate the checkout and launch of NASA's next generation SLS vehicle in order to enable human exploration through deep space. SCCS is made up of complex software that will control and monitor the Space Launch System rocket and Orion spacecraft. Once it is fully developed, SCCS will be a large improvement to previous software since it takes advantage of modern computers and information making it faster and more reliable than the software used previously on the Shuttle program. The software will be tailored to the specific needs of the Space Launch System (SLS) and Orion spacecraft. These three projects will be brought together for the launch of Exploration Mission-1.

Mackh, Katherine↗
NASA NTRS2022

SWS TechTalk Systems Modelling for SWS Safety Demonstrator 1 (SD-1): Wildfire Response Operations

Build out a System Safety Model for System-Wide Safety’s first Technical Challenge 5 (TC5) Safety Demonstrator (SD-1), which will be a demonstration of an In-Time Aviation Safety Management System in emerging wildfire response operations. Supporting the Systems Engineer and using Model-Based Systems Engineering (MBSE) practices, languages, and tools. Summer 2022 SD1 milestones: TC5-03-01 Initial Stakeholder Engagement Concept of Operations Development milestone and the upcoming TC5-03-02 Identification of key gaps and prioritization of NASA, SWS milestone.

model-based systems engineering↗
NASA NTRS2019

Medical System Concept of Operations for Mars Exploration Mission-11: Exploration Medical Capability (ExMC) Element - Human Research Program

NASA’s exploration missions to Mars will have durations of 2-3 years and will take humans farther away from Earth than ever before. This will result in a paradigm shift for mission planning, spacecraft design, human systems integration, and in-flight medical care. Constraints on real-time communication, resupply, and medical evacuation are major architectural drivers. These constraints require medical system development to be tightly integrated with mission and vehicle design to provide crew autonomy and enable mission success. This concept of operations provides a common vision of medical care for developing a medical system for Mars exploration missions. It documents an overview of the stakeholder needs and goals of a medical system and provides examples of the types of activities the system will be used for during the mission. Development of the concept of operations considers mission variables such as distance from Earth, duration of mission, time to definitive medical care, communication protocols between crewmembers and ground support, personnel capabilities and skill sets, medical hardware and software, and medical data management. The information provided in this document informs the ExMC Systems Engineering effort to define the functions to be provided by the medical system. In addition, this concept of operations will inform the subsequent systems engineering process of developing technical requirements, system architectures, interfaces, and verification and validation approaches for the medical system. This document supports the closure of ExMC Gap Med01: We do not have a concept of operations for medical care during exploration missions, corresponding to the ExMC-managed human system risk: Risk of Adverse Health Outcomes & Decrements in Performance due to Inflight Medical Conditions. This document is applicable to the ExMC Element Systems Engineering process and may be used for collaboration within the Human Research Program.

Urbina, Michelle↗
DOE OSTI2022

Modeling gas breakthrough and flow phenomena through engineered barrier systems using a discrete fracture approach

Compacted clays are being considered to build engineered barrier systems (EBS) intended for the safe isolation of high-level nuclear waste (HLW) and spent nuclear fuel (SNF). The corrosion of the metallic canister containing the HLW/SNF will lead to the generation and buildup of the gas pressure in the more internal part of the clay buffer. This phenomenon would eventually trigger the formation and propagation of fractures in the clay barrier, jeopardizing its safety functions. Here, in this work, we propose to use the fragmentation technique (MFT) to model evolving fractures in clays triggered by gas pressurization. The MFT has been successfully used to model the formation of fractures in concrete, drying cracks in soil, hydraulic and thermo-fractures in rocks. In this work, we extend the MFT to deal with multiphase fluid flow in deformable porous media, and we upgraded a fully coupled computer finite element code using the extended technique. The proposed approach is first verified against analytical solutions and is then applied to model gas breakthrough experiments in clays. A very satisfactory performance of the method is observed in all the analyses, showing the potential of the MFT to tackle multiphase flow problems in deformable porous media with evolving discontinuities.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗