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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 1,225 records · Page 68

All sources NASA NTRS DOE OSTI

NASA NTRS2004

Human Motion Tracking at Marshall Space Flight Center's Collaborative Engineering Center ANVIL

The installation and use of electromagnetic human motion trackers requires a specially designed and metal-free environment for optimal performance. Such an area is not readily available at the Marshall Space Flight Center Collaborative Engineering Center ANVIL. Our paper details a systems engineering approach to installing and operating Ascension Technologies Ethernet MotionStar tracking system in a sub-optimal environment, used with the JACK human computer model's motion capture capabilities. We also discuss how this system is integrated into the Marshall Space Flight Center's Human Engineering process.

Henderson, Steven J.↗

NASA NTRS2002

Gas/Liquid Separator Being Developed for Microgravity

The examination and research of how liquids and gases behave in very low gravity will improve our understanding of the behavior of fluids on Earth. The knowledge of multiphase fluid behavior is applicable to many industries on Earth, including the pharmaceutical, biotechnology, chemical, and nuclear industries, just to name a few. In addition, this valuable knowledge applies very well to the engineering and design of microgravity materials processing and of life-support systems for extended space flight. Professors Ashok Sangani of Syracuse University and Donald Koch of Cornell University are principal investigators in the Microgravity Fluid Physics Program, which is managed and sponsored by the NASA Glenn Research Center. Their flight experiment entitled "Microgravity Observations of Bubble Interactions" (MOBI) is planned for operation in the Fluids and Combustion Facility aboard the International Space Station.

Hoffmann, Monica I.↗

NASA NTRS2011

Engineering the System and Technical Integration

Approximately 80% of the problems encountered in aerospace systems have been due to a breakdown in technical integration and/or systems engineering. One of the major challenges we face in designing, building, and operating space systems is: how is adequate integration achieved for the systems various functions, parts, and infrastructure? This Contractor Report (CR) deals with part of the problem of how we engineer the total system in order to achieve the best balanced design. We will discuss a key aspect of this question - the principle of Technical Integration and its components, along with management and decision making. The CR will first provide an introduction with a discussion of the Challenges in Space System Design and meeting the challenges. Next is an overview of Engineering the System including Technical Integration. Engineering the System is expanded to include key aspects of the Design Process, Lifecycle Considerations, etc. The basic information and figures used in this CR were presented in a NASA training program for Program and Project Managers Development (PPMD) in classes at Georgia Tech and at Marshall Space Flight Center (MSFC). Many of the principles and illustrations are extracted from the courses we teach for MSFC.

Blair, J. C.↗

NASA NTRS2013

Spaceport Processing System Development Lab

The Spaceport Processing System Development Lab (SPSDL), developed and maintained by the Systems Hardware and Engineering Branch (NE-C4), is a development lab with its own private/restricted networks. A private/restricted network is a network with restricted or no communication with other networks. This allows users from different groups to work on their own projects in their own configured environment without interfering with others utilizing their resources in the lab. The different networks being used in the lab have no way to talk with each other due to the way they are configured, so how a user configures his software, operating system, or the equipment doesn't interfere or carry over on any of the other networks in the lab. The SPSDL is available for any project in KSC that is in need of a lab environment. My job in the SPSDL was to assist in maintaining the lab to make sure it's accessible for users. This includes, but is not limited to, making sure the computers in the lab are properly running and patched with updated hardware/software. In addition to this, I also was to assist users who had issues in utilizing the resources in the lab, which may include helping to configure a restricted network for their own environment. All of this was to ensure workers were able to use the SPSDL to work on their projects without difficulty which would in turn, benefit the work done throughout KSC. When I wasn't working in the SPSDL, I would instead help other coworkers with smaller tasks which included, but wasn't limited to, the proper disposal, moving of, or search for essential equipment. I also, during the free time I had, used NASA's resources to increase my knowledge and skills in a variety of subjects related to my major as a computer engineer, particularly in UNIX, Networking, and Embedded Systems.

Systems Engineering↗

NASA NTRSDate not supplied

Rapid Development of Instrument Thermal Models: Perspectives and Guidelines from NASA Goddard’s Instrument Design Laboratory

The Instrument Design Laboratory (IDL), part of NASA Goddard Space Flight Center’s Integrated Design Center (IDC), is a concurrent and collaborative environment which allows for rapid development of science instrumentation concepts within the span of less than two weeks. Science goals set by a Principal Investigator from government, industry or academia are translated into engineering requirements, from which a team of engineers spanning multiple disciplines use an established study process and a suite of analysis tools to work towards an instrument point design. As part of this process, a staff thermal engineer is tasked with designing a thermal control system which meets all incoming thermal requirements, while iterating real-time with other subsystems to ensure compatibility and functionality as a completed system. Thermal engineers on spaceflight projects typically have weeks or months to develop thermal models. However, the severe time limitation in this conceptual study setting makes thermal design particularly difficult, as rapid thermal modeling solely over the span of a few days is required to develop the instrument thermal design and understand the performance over its intended mission, especially if the instrument concept contains multiple thermal challenges such as dynamic environments or high heat dissipating components. In this paper, the authors provide a condensed guide for the most efficient ways to develop thermal models and conduct thermal analysis within the span of one-to-two weeks, as informed by decades of design experience and best practices in the IDL. The authors also focus on quick methods for determining worst-case thermal environments, deciding which modeling details are essential at this early phase, and quantifying the engineering resources necessary for thermal control. This paper concludes with specific thermal design tips for different instrument types across the electromagnetic spectrum.

Kan Yang↗

NASA NTRSDate not supplied

Core Stage TVC Systems Engineering Challenges in Reusing Heritage Hardware

The Space Launch System (SLS) Core Stage (CS) Thrust Vector Control (TVC) system is comprised of 8 mechanical feedback Shuttle heritage Type III TVC actuators and four RS-25 engines, each attached to a Shuttle heritage gimbal block/bearing. Two actuators are used to move each engine in two planes perpendicular to one another (i.e., pitch and yaw). The TVC system design leverages hardware from the Space Shuttle program as well as new hardware designed specifically for the Core Stage. The Space Shuttle heritage hardware directly reused on SLS includes the Orbiter TVC hydraulic servo-actuators (with two slight design modifications), the Orbiter hydraulic circulation pumps, the Orbiter gimbal block/bearing, and the Solid Rocket Booster hydraulic pumps. The Core Auxiliary Power Unit (CAPU) is derived from the Orbiter Auxiliary Power Unit (APU). The Orbiter and Solid Rocket Booster APU turbines are powered by hot gas produced by catalyzed hydrazine decomposition. On the SLS Core Stage, the CAPU turbine is spun using cold gas tapped-off from the RS-25 to CS liquid hydrogen autogenous pressurization line. While direct reuse or slight modification of existing hardware may seem to be a triple-win for a program in cost, schedule, and technical risk mitigation, those benefits can only be realized when its degree of application in a new system is carefully and thoughtfully managed. The heritage hardware reuse should be prescribed within the heritage design capability and reuse environments must lie within the envelope of heritage qualification testing. Despite the significant test and flight experience of the Shuttle heritage hardware components, successful integration with the newly designed CS TVC components and incorporation into the stage design proved to be a challenge which required re-qualification of the heritage hardware as well as thorough integrated testing to support flight certification. Examples of the challenges that were overcome include: re-qualifying heritage hardware to survive new shock and vibration environments, certifying performance of extensively modified heritage hardware, regenerating design insight due to lack of available heritage vendor data, showing compliance to modern structural design standards, translation of heritage requirements for analog avionics to modern digital avionics, and interfacing heritage mechanical hardware with newly designed avionics. This paper is the second installment in a seven-paper series surveying the design, engineering, test validation, and flight performance of the Core Stage Thrust Vector Control system. This paper will discuss several engineering challenges encountered during the development process for SLS CS TVC and how they were successfully overcome to reach flight readiness.

Thrust Vector Control↗

NASA NTRSDate not supplied

Space Launch System: Core Stage Thrust Vector Control Systems Engineering Challenges in Reusing Heritage Hardware

Thrust Vector Control↗

DOE OSTI2017

Sandia Engineering Analysis Code Access System v. 2.0.1

The Sandia Engineering Analysis Code Access System (SEACAS) is a suite of preprocessing, post processing, translation, visualization, and utility applications supporting finite element analysis software using the Exodus database file format.

Sjaardema, Gregory D.↗

DOE OSTI2017

Determining appropriate data analytics for transformer health monitoring - 107

Transformers are vital assets for the safe, reliable and cost-effective operation of nuclear power plants. The unexpected failure of a transformer can lead to different consequences ranging from a lack of export capability, with the corresponding economic penalties, to catastrophic failure, with the associated health, safety and economic effects. Condition monitoring techniques examine the health of the transformer periodically, with the aim to identify early indicators of anomalies. However, many transformer failures occur because diagnostic and monitoring models do not identify degraded conditions in time. Therefore, health monitoring is an essential component to transformer life cycle management. Existing tools for transformer health monitoring use traditional dissolved gas analysis based diagnostics techniques. With the advance of prognostics and health management (PHM) applications, we can enhance traditional transformer health monitoring techniques using PHM analytics. The design of an appropriate data analytics system requires a multi-stage design process including: (i) specification of engineering requirements; (ii) characterization of existing data sources and analytics to identify complementary techniques; (iii) development of the functional specification of the analytics suite to formalize its behavior, and finally (iv) deployment, validation, and verification of the functional requirements in the final platform. Accordingly, in this paper we propose a transformer analytics suite which incorporates anomaly detection, diagnostics, and prognostics modules in order to complement existing tools for transformer health monitoring. (authors)

42 ENGINEERING↗

NASA NTRS1998

An Object Model for a Rocket Engine Numerical Simulator

Rocket Engine Numerical Simulator (RENS) is a packet of software which numerically simulates the behavior of a rocket engine. Different parameters of the components of an engine is the input to these programs. Depending on these given parameters the programs output the behaviors of those components. These behavioral values are then used to guide the design of or to diagnose a model of a rocket engine "built" by a composition of these programs simulating different components of the engine system. In order to use this software package effectively one needs to have a flexible model of a rocket engine. These programs simulating different components then should be plugged into this modular representation. Our project is to develop an object based model of such an engine system. We are following an iterative and incremental approach in developing the model, as is the standard practice in the area of object oriented design and analysis of softwares. This process involves three stages: object modeling to represent the components and sub-components of a rocket engine, dynamic modeling to capture the temporal and behavioral aspects of the system, and functional modeling to represent the transformational aspects. This article reports on the first phase of our activity under a grant (RENS) from the NASA Lewis Research center. We have utilized Rambaugh's object modeling technique and the tool UML for this purpose. The classes of a rocket engine propulsion system are developed and some of them are presented in this report. The next step, developing a dynamic model for RENS, is also touched upon here. In this paper we will also discuss the advantages of using object-based modeling for developing this type of an integrated simulator over other tools like an expert systems shell or a procedural language, e.g., FORTRAN. Attempts have been made in the past to use such techniques.

Mitra, D.↗

NASA NTRS2010

Control Design for a Generic Commercial Aircraft Engine

This paper describes the control algorithms and control design process for a generic commercial aircraft engine simulation of a 40,000 lb thrust class, two spool, high bypass ratio turbofan engine. The aircraft engine is a complex nonlinear system designed to operate over an extreme range of environmental conditions, at temperatures from approximately -60 to 120+ F, and at altitudes from below sea level to 40,000 ft, posing multiple control design constraints. The objective of this paper is to provide the reader an overview of the control design process, design considerations, and justifications as to why the particular architecture and limits have been chosen. The controller architecture contains a gain-scheduled Proportional Integral controller along with logic to protect the aircraft engine from exceeding any limits. Simulation results illustrate that the closed loop system meets the Federal Aviation Administration s thrust response requirements

Csank, Jeffrey↗

DOE OSTI2020

Recent Progress in the Engineering of Polymeric Membranes for CO2 Capture from Flue Gas

CO2 capture from coal- or natural gas-derived flue gas has been widely considered as the next opportunity for the large-scale deployment of gas separation membranes. Despite the tremendous progress made in the synthesis of polymeric membranes with high CO2/N2 separation performance, only a few membrane technologies were advanced to the bench-scale study or above from a highly idealized laboratory setting. Therefore, the recent progress in polymeric membranes is reviewed in the perspectives of capture system energetics, process synthesis, membrane scale-up, modular fabrication, and field tests. These engineering considerations can provide a holistic approach to better guide membrane research and accelerate the commercialization of gas separation membranes for post-combustion carbon capture.

20 FOSSIL-FUELED POWER PLANTS↗

DOE OSTI2015

Bench Scale Thin Film Composite Hollow Fiber Membranes for Post-Combustion Carbon Dioxide Capture

GE Global Research, Idaho National Laboratory (INL), Georgia Institute of Technology (Georgia Tech), and Western Research Institute (WRI) proposed to develop high performance thin film polymer composite hollow fiber membranes and advanced processes for economical post-combustion carbon dioxide (CO 2 ) capture from pulverized coal flue gas at temperatures typical of existing flue gas cleanup processes. The project sought to develop and then optimize new gas separations membrane systems at the bench scale, including tuning the properties of a novel polyphosphazene polymer in a coating solution and fabricating highly engineered porous hollow fiber supports. The project also sought to define the processes needed to coat the fiber support to manufacture composite hollow fiber membranes with high performance, ultra-thin separation layers. Physical, chemical, and mechanical stability of the materials (individual and composite) towards coal flue gas components was considered via exposure and performance tests. Preliminary design, technoeconomic, and economic feasibility analyses were conducted to evaluate the overall performance and impact of the process on the cost of electricity (COE) for a coal-fired plant including capture technologies. At the onset of the project, Membranes based on coupling a novel selective material polyphosphazene with an engineered hollow fiber support was found to have the potential to capture greater than 90% of the CO 2 in flue gas with less than 35% increase in COE, which would achieve the DOE-targeted performance criteria. While lab-scale results for the polyphosphazene materials were very promising, and the material was incorporated into hollow-fiber modules, difficulties were encountered relating to the performance of these membrane systems over time. Performance, as measured by both flux of and selectivity for CO 2 over other flue gas constituents was found to deteriorate over time, suggesting a system that was more dynamic than initially hypothesized. These phenomena are believed to be associated with the physical and mechanical properties of the separation material, rather than chemical degradation by flue gas or one of its constituents. Strategies to improve the composite systems via alternate chemistries and processing techniques were only partially successful in creating a more robust system, but the research provided critical insight into the barriers to engineering sophisticated composite systems for gas separation. Promising concepts, including a re-engineering of the separation material with interpenetrating polymer networks were identified which may prove useful to future efforts in this field.

36 MATERIALS SCIENCE↗

DOE OSTI2013

Applying QMU to Nuclear Weapon Stewardship

Quantification of Margins and Uncertainty (QMU) is a principle means and metric by which nuclear weapons performance is measured. At Lawrence Livermore National Laboratory (LLNL), Nuclear weapon QMU is predominately a Physics assessment of the performance margin and associated uncertainties of not achieving the designed nuclear performance. To more completely apply QMU to Nuclear Weapon Stewardship, a Systems Engineering or systematic approach is being employed to identify and define requirements, allowing assessment of performance with QMU. This paper describes the basics of QMU and how it is applied below the highest level nuclear performance function down and throughout the nuclear weapon design architecture. The intended audience for this paper is a novice QMU practitioner at LLNL. The application of QMU to the entire set of nuclear weapon functions demands a broad engagement of Science and Engineering disciplines. Using a hierarchical flow-down requirements structure, performance functions and failure modes are identified for all levels of system requirements. There can be multiple failure modes per functional requirement. For each function there is a spectrum of possible outputs that can vary from outright failure to excellent performance. The possible consequences and impacts on the next higher level functions will also vary. Since performance variations exist in a weapon functional hierarchy, the assessment process needs and benefits from a system perspective. Incorporating QMU into assessments using a Systems Engineering approach to stockpile management provides a means to quantify weapon performance risks against a multitude of possible failure modes and from the highest level functions down to the lowest level component functionality. Performance risk management is a core practice of nuclear weapon management. Assessing the likelihood and consequences of the many possible failure modes is done yearly as part of Annual Assessment Reviews (AAR). When annual surveillance discovers an anomaly defect as part of weapon surveillance, investigations are launched and QMU is a key tool for quantifying performance impacts. QMU assessments are separated into two pieces, failure mode assessments and QMU analysis.

42 ENGINEERING↗

NASA NTRS1985

A computer simulation of the turbocharged turbo compounded diesel engine system: A description of the thermodynamic and heat transfer models

A computer simulation of the turbocharged turbocompounded direct-injection diesel engine system was developed in order to study the performance characteristics of the total system as major design parameters and materials are varied. Quasi-steady flow models of the compressor, turbines, manifolds, intercooler, and ducting are coupled with a multicylinder reciprocator diesel model, where each cylinder undergoes the same thermodynamic cycle. The master cylinder model describes the reciprocator intake, compression, combustion and exhaust processes in sufficient detail to define the mass and energy transfers in each subsystem of the total engine system. Appropriate thermal loading models relate the heat flow through critical system components to material properties and design details. From this information, the simulation predicts the performance gains, and assesses the system design trade-offs which would result from the introduction of selected heat transfer reduction materials in key system components, over a range of operating conditions.

Assanis, D. N.↗

DOE OSTI2019

Seismic Testing of Glovebox Feedthrough Connectors and Vacuum Pumps

In the design of tritium processing systems, the glovebox stripper system processes the glovebox atmosphere to recover tritium released inside the glovebox confinement. The glovebox stripper system must also be capable of processing the additional in-leakage caused by a Design Basis Accident (DBA) earthquake, in order to maintain the glovebox pressure negative relative to the room. However, it is unknown how much additional leakage occurs from electrical bulkhead feedthrough connectors after a DBA event. As there are dozens of these connectors on a tritium glovebox system, the potential increase in in-leakage can be significant. One vital part of the glovebox stripper system are the vacuum pumps that maintain the negative atmosphere of the glovebox following a DBA earthquake. The pumps must be able to operate following an earthquake. One candidate pump is the Senior Aerospace MB-602 Metal Bellows (Met-Bel) pump. A second alternative is the hermetically sealed Edwards Vacuum nXDS15iC Scroll Pump. The Edwards scroll pump is potentially a less expensive alternative to the Met-Bel pumps, but it is unknown if this scroll pumps will survive a DBA accident and remain operational. In order to determine the electrical feedthrough in-leakage and the candidate pumps’ survivability, a seismic test was performed to simulate a DBA earthquake. This report summarizes the results of seismic test, including helium leak rates and functionality tests for the electrical feedthroughs and vacuum pumps. All components had pre- and post-test leak rates less than the threshold valve of 1x10 -6 scc per sec.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

DOE OSTI2017

Soot and Spectral Radiation Modeling in ECN Spray A and in Engines

The amount of soot formed in a turbulent combustion system is determined by a complex system of coupled nonlinear chemical and physical processes. Different physical subprocesses can dominate, depending on the hydrodynamic and thermochemical environments. Similarly, the relative importance of reabsorption, spectral radiation properties, and molecular gas radiation versus soot radiation varies with thermochemical conditions, and in ways that are difficult to predict for the highly nonhomogeneous in-cylinder mixtures in engines. Here it is shown that transport and mixing play relatively more important roles as rate-determining processes in soot formation at engine-relevant conditions. It is also shown that molecular gas radiation and spectral radiation properties are important for engine-relevant conditions.

33 ADVANCED PROPULSION SYSTEMS↗

NASA NTRS1975

Amplification of Reynolds number dependent processes by wave distortion

A system using a hot-wire transducer as an analog of a liquid droplet of propellant was employed to investigate the ingredients of the acoustic instability of liquid-propellant rocket engines. It was assumed that the combustion process was vaporization-limited and that the combustion chamber was acoustically similar to a closed-closed right-circular cylinder. Before studying the hot-wire closed-loop system (the analog system), a microphone closed-loop system, which used the response of a microphone as the source of a linear feedback exciting signal, was investigated to establish the characteristics of self-sustenance of acoustic fields. Self-sustained acoustic fields were found to occur only at resonant frequencies of the chamber. In the hot-wire closed-loop system, the response of hot-wire anemometer was used as the source of the feedback exciting signal. The self-sustained acoustic fields which developed in the system were always found to be harmonically distorted and to have as their fundamental frquency a resonant frequency for which there also existed a second resonant frequency which was approximately twice the fundamental frequency.

Ventrice, M. B.↗