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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 325 records · Page 18
All sourcesNASA NTRSDOE OSTI
NASA NTRS1972

Training and certification program of the operating staff for a 90-day test of a regenerative life support system

Prior to beginning a 90-day test of a regenerative life support system, a need was identified for a training and certification program to qualify an operating staff for conducting the test. The staff was responsible for operating and maintaining the test facility, monitoring and ensuring crew safety, and implementing procedures to ensure effective mission performance with good data collection and analysis. The training program was designed to ensure that each operating staff member was capable of performing his assigned function and was sufficiently cross-trained to serve at certain other positions on a contingency basis. Complicating the training program were budget and schedule limitations, and the high level of sophistication of test systems.

Source record↗
NASA NTRS2005

Calculated X-ray Intensities Using Monte Carlo Algorithms: A Comparison to Experimental EPMA Data

Monte Carlo (MC) modeling has been used extensively to simulate electron scattering and x-ray emission from complex geometries. Here are presented comparisons between MC results and experimental electron-probe microanalysis (EPMA) measurements as well as phi(rhoz) correction algorithms. Experimental EPMA measurements made on NIST SRM 481 (AgAu) and 482 (CuAu) alloys, at a range of accelerating potential and instrument take-off angles, represent a formal microanalysis data set that has been widely used to develop phi(rhoz) correction algorithms. X-ray intensity data produced by MC simulations represents an independent test of both experimental and phi(rhoz) correction algorithms. The alpha-factor method has previously been used to evaluate systematic errors in the analysis of semiconductor and silicate minerals, and is used here to compare the accuracy of experimental and MC-calculated x-ray data. X-ray intensities calculated by MC are used to generate a-factors using the certificated compositions in the CuAu binary relative to pure Cu and Au standards. MC simulations are obtained using the NIST, WinCasino, and WinXray algorithms; derived x-ray intensities have a built-in atomic number correction, and are further corrected for absorption and characteristic fluorescence using the PAP phi(rhoz) correction algorithm. The Penelope code additionally simulates both characteristic and continuum x-ray fluorescence and thus requires no further correction for use in calculating alpha-factors.

Carpenter, P. K.↗
NASA NTRS2007

Pharmacotherapeutics of Intranasal Scopolamine: FDA Regulations and Procedures for Clinical Applications

Space Motion Sickness (SMS) is commonly experienced by astronauts and often requires treatment with medications during the early flight days of a space mission. Bioavailability of oral (PO) SMS medications is often low and highly variable; additionally, physiological changes in a microgravity environment exacerbate variability and decrease bioavailability. These factors prompted NASA to develop an intranasal dosage form of scopolamine (INSCOP) suitable for the treatment of SMS. However, to assure safety and efficacy of treatment in space, NASA physicians prescribe commercially available pharmaceutical products only. Development of a pharmaceutical preparation for clinical use must follow distinct clinical phases of testing, phase I through IV to be exact, before it can be approved by the FDA for approval for clinical use. After a physician sponsored Investigative New Drug (IND) application was approved by the FDA, a phase I clinical trial of INSCOP formulation was completed in normal human subjects and results published. The current project includes three phase II clinical protocols for the assessment of pharmacokinetics and pharmacodynamics (PK/PD), efficacy, and safety of INSCOP. Three clinical protocols that were submitted to FDA to accomplish the project objectives: 1) 002-A, a FDA Phase II dose ranging study with four dose levels between 0.1 and 0.4 mg in 12 subjects to assess PK/PD, 2) 002-B, a phase II clinical efficacy study in eighteen healthy subjects to compare efficacy of 0.2 (low dose) and 0.4 mg (high dose) INSCOP for prophylactic treatment of motion-induces (off-axis vertical rotation) symptoms, and (3) 002-C, a phase II clinical study with twelve subjects to determine bioavailability and pharmacodynamics of two doses (0.2 and 0.4 mg) of INSCOP in simulated microgravity, antiorthostatic bedrest. All regulatory procedures were competed that include certification for Good laboratory Procedures by Theradex , clinical documentation, personnel training, selection of clinical research operations contractor, data capturing and management, and annual reporting of results to FDA were successfully completed. Protocol 002-A was completed and sample and data analysis is currently in progress. Protocol 002-B is currently in progress at Dartmouth Hitchcock Medical Center and Protocol 002-C has been submitted to the FDA and will be implemented at the same contractor site as 002-A. An annual report was filed as required by FDA on the results of Protocol 002-A. Once all the three Phase II protocols are completed, a New Drug Administration application will be filed with FDA for Phase III clinical assessment and approval for marketing of the formulation. A commercial vendor will be identified for this phase. This is critical for making this available for treatment of SMS in astronauts and military personnel on duty. Once approved by FDA, INSCOP can be also used by civilian population for motion sickness associated with recreational travel and other ailments that require treatment with anticholinergic drugs.

Das, H.↗
NASA NTRSDate not supplied

Conceptual Design Trade Studies for Acoustic Predictions of the NASA UAM Tiltrotor Reference Vehicle

A toolchain of low-and mid-fidelity tools is applied to NASA’s Urban Air Mobility tiltrotor reference vehicle to quantify trades in sizing, performance, and noise at the conceptual design level. The process includes conceptual sizing, comprehensive analysis, and acoustic analysis to design and analyze versions of the concept tiltrotor with differing design variables. Rotor tip speed is the primary design variable studied, with blade twist, blade taper, and blade number also considered. The noise metrics used are the FAA/EASA certification Effective Perceived Noise Levels for takeoff, flyover, and approach. Certification condition noise is calculated for all conditions in both conversion and airplane flight modes, with airplane mode flight resulting in noise 10-25EPNdB quieter than conversion mode and tip speed variation providing noise reduction up to 9EPNdB.

Acoustic↗
NASA NTRS1975

Measurements and analysis of aircraft airframe noise

Flyover measurements of the airframe noise of AeroCommander, JetStar, CV-990, and B-747 aircraft are presented. Data are shown for both cruise and landing configurations. Correlations between airframe noise and aircraft parameters are developed and presented. The landing approach airframe noise for the test aircraft was approximately 10 EPNdB below present FAA certification requirements.

Putnam, T. W.↗
NASA NTRS1986

Application of Weibull analysis to SSME hardware

Generally, it has been documented that the wearing of engine parts forms a failure distribution which can be approximated by a function developed by Weibull. The purpose here is to examine to what extent the Weibull distribution approximates failure data for designated engine parts of the Space Shuttle Main Engine (SSME). The current testing certification requirements will be examined in order to establish confidence levels. An examination of the failure history of SSME parts/assemblies (turbine blades, main combustion chamber, or high pressure fuel pump first stage impellers) which are limited in usage by time or starts will be done by using updated Weibull techniques. Efforts will be made by the investigator to predict failure trends by using Weibull techniques for SSME parts (turbine temperature sensors, chamber pressure transducers, actuators, and controllers) which are not severely limited by time or starts.

Gray, L. A. B.↗
NASA NTRS2017

CMH-17 Volume 5 Ceramic Matrix Composites

A wide range of issues must be addressed during the process of certifying CMC (ceramic matrix composite) components for use in commercial aircraft. The Composite Materials Handbook-17, Volume 5, Revision A on ceramic matrix composites has just been revised to help support FAA certification of CMCs for elevated temperature applications. The handbook supports the development and use of CMCs through publishing and maintaining proven, reliable engineering information and standards that have been thoroughly reviewed. Volume 5 contains detailed sections describing CMC materials processing, design analysis guidelines, testing procedures, and data analysis and acceptance. A review of the content of this latest revision will be presented along with a description of how CMH-17, Volume 5 could be used by the FAA (Federal Aviation Administration) and others in the future.

characterization↗
NASA NTRS1994

Modal Test Technology as Non-Destructive Evaluation of Space Shuttle Structures

Modal test and analysis Is being used for nondestructive evaluation of Space Shuttle structures. The purpose of modal testing is to measure the dynamic characteristics of a structure to extract its resonance frequencies, damping, and mode shapes. These characteristics are later compared to subsequently acquired characteristics. Changes in the modal characteristics indicate damage in the structure. Use of modal test technology as a damage detection tool was developed at JSC during the Shuttle acoustic certification program and subsequent test programs. The Shuttle Modal Inspection System was created in order to inspect areas that are impossible or impractical to inspect with conventional methods. Areas on which this technique has been applied include control surfaces, which are covered with thermal protection tiles, and the Forward Reaction Control Module, which is a frame structure that supports various tanks, thrusters, and fluid lines, which requires major disassembly to inspect. This paper traces the development of the technology, gives a status of its implementation on the Shuttle, explains challenges involved in implementing this type of inspection program, and suggests future improvements in data analysis and interpretation. Dual-use applications of the technology include inspections of bridges, oil-platforms, and aircraft.

Micheal S Grygler↗
NASA NTRS2012

High Energy/LET Radiation EEE Parts Certification Handbook

Certifying electronic components is a very involved process. It includes pre-coordination with the radiation test facility for time, schedule and cost, as well as intimate work with designers to develop test procedures and hardware. It also involves work with radiation engineers to understand the effects of the radiation field on the test article/setup as well as the analysis and production of a test report. The technical content of traditional ionizing radiation testing protocol is in wide use and generally follows established standards (ref. Appendix C). This document is not intended to cover all these areas but to cover the methodology of using Variable Depth Bragg Peak (VDBP) to accomplish the goal of characterizing an electronic component. The Variable Depth Bragg Peak (VDBP) test method is primarily used for deep space applications of electronics. However, it can be used on any part for any radiation environment, especially those parts where the sensitive volume cannot be reached by the radiation beam. An example of this problem would be issues that arise in de-lidding of parts or in parts with flip-chip designs, etc. The VDBP method is ideally suited to test modern avionics designs which increasingly incorporate commercial off-the-shelf (COTS) parts and units. Johnson Space Center (JSC) developed software provides assistance to users in developing the radiation characterization data from the raw test data.

Reddell, Brandon↗
NASA NTRSDate not supplied

Analysis of the Tropospheric Doppler Radar Wind Profiler Measurement Accuracy

- The Tropospheric Doppler Radar Wind Profiler (TDRWP) is a wind measurement instrument at NASA’s Kennedy Space Center, co-located on the United States Space Force’s (USSF) Eastern Range (ER) at the Cape Canaveral Space Force Station (CCAFS), that generates atmospheric wind profiles which are utilized in the design, certification and operations of various launch vehicles - NASA’s Space Launch System (SLS) - Commercial launch vehicles - NASA Crew-4 in April 2022 was first NASA crewed mission to use TDRWP - Composed of twenty antenna sectors and transmitter unit pairs which operate at 48 MHz - TDRWP data is required for day-of-launch structural margin and performance assessments

Meghan E. Carrico↗
NASA NTRS1977

A Representative Shuttle Environmental Control System

The Representative Shuttle Environmental Control System (RSECS) provides a ground test bed to be used in the early accumulation of component and system operating data, the evaluation of potential system improvements, and possibly the analysis of Shuttle Orbiter test and flight anomalies. Selected components are being subjected to long term tests to determine endurance and corrosion resistance capability prior to Orbiter vehicle experience. Component and system level tests in several cases are being used to support flight certification of Orbiter hardware. These activities are conducted as a development program to allow for timeliness, flexibility, and cost effectiveness not possible in a program burdened by flight documentation and monitoring constraints.

Brose, H. F.↗
NASA NTRS2000

Software Released by LEWICE 2.0 Ice Accretion Software Development Project

Computational icing simulation methods are making the transition from the realm of research to commonplace use in design and certification. As such, standards of software management, design, validation, and documentation must be adjusted to accommodate the increased expectations of the user community with respect to accuracy, reliability, capability, and usability. With this in mind, in collaboration with Glenn's Engineering Design and Analysis Division, the Icing Branch of the NASA Glenn Research Center at Lewis Field began a software improvement project focused on the two-dimensional ice accretion simulation tool LEWICE. This project is serving as an introduction to the concepts of software management and is intended to serve as a pilot project for future icing simulation code development. The LEWICE 2.0 Software Development Project consisted of two major elements: software management and software validation. The software management element consisted of identifying features of well-designed and well-managed software that are appropriate for an analytical prediction tool such as LEWICE and applying them to a revised version of the code. This element included tasks such as identification of software requirements, development and implementation of coding standards, and implementation of software revision control practices. With the application of these techniques, the LEWICE ice accretion code became a more stable and reliable software product. In addition, the lessons learned about software development and maintenance can be factored into future software projects at the outset. The software validation activity was an integral part of our effort to make LEWICE a more accurate and reliable analysis tool. Because of the efforts taken to extensively validate this software, LEWICE 2.0 is more robust than previous releases and can reproduce results accurately across several computing platforms. It also differs from previous versions in the extensive quantitative comparisons of its results with a data base of ice shapes that were generated in Glenn's Icing Research Tunnel. The results of the shape comparisons were analyzed to determine the range of meteorological conditions under which LEWICE 2.0 is within the repeatability found for ice shapes obtained from experiments. These comparisons show that the average variation of LEWICE 2.0 from experimental data is 7.2 percent, whereas the overall variability of the experimental data is 2.5 percent. The LEWICE 2.0 Software Development Project resulted in the release, at the recent Icing Branch LEWICE Workshop, of a more useful and robust analysis tool than was previously available to the icing community. The lessons learned from this project will be applied to the Icing Branch s future software development efforts.

Potapczuk, Mark G.↗
NASA NTRS1991

Structural dynamics: Probabilistic structural analysis methods. Program overview

A brief description is provided of the fundamental aspects of a quantification process. Progress since the last structural durability conference in 1989 is summarized. The methodology to date and that to be developed during the life of the program is presented. The uncertain factors are presented. The approach is outlined that is required to achieve component and/or system certification in the shortest possible time for affordable reliability risk. Two new elements appear in a block diagram: (1) uncertainties in human factor, and (2) uncertainties in the computer code. Research to quantify the uncertainties in the human factor was initiated and is discussed.

Chamis, Christos C.↗
NASA NTRS2010

Certification

Objective 1: Provide regulators with a methodology for development of airworthiness requirements for certification of UAS. a) Rationale: a comprehensive methodology does not currently exist to support development of regulation for certification of UAS. Regulation is essential to enable routine access to the NAS. b) Approach: 1) assess existing approaches and classification schemes for deriving acceptable means of compliance to airworthiness requirements. 2) investigate a service-based approach to classification of UAS. 3) conduct comparative analysis of different methodologies. 4) work with FAA to determine best approach and conduct case study. 5) participate in regulatory/standards organizations developing safety and performance requirements for UAS. Objective 2: Provide regulators and industry with hazard and risk-related data to support criteria for UAS type design. a) Rationale: There is presently little UAS specific data (incident, accident, and reliability), especially in a civil context, to support risk assessment and development of standards and regulation. b) Approach: Identify gaps in existing data, provide measured data as needed, and formulate recommendations by: 1) evaluating UAS incident/accident data collection efforts and determining additional support necessary for regulation. 2) assessing UAS-specific hazards and risks. 3) evaluating need for reliability data for UAS-unique systems, components and subsystem, and determining additional measurement requirements. 4) developing guidance and best practices for UAS type design.

Hayhurst, Kelly↗
NASA NTRS2017

Update on CMH-17 Volume 5 Ceramic Matrix Composites

A wide range of issues must be addressed during the process of certifying CMC (ceramic matrix composite) components for use in commercial aircraft. The Composite Materials Handbook-17, Volume 5, Revision A on ceramic matrix composites has just been revised to help support FAA certification of CMCs for elevated temperature applications. The handbook supports the development and use of CMCs through publishing and maintaining proven, reliable engineering information and standards that have been thoroughly reviewed. Volume 5 contains detailed sections describing CMC materialsprocessing design, analysisguidelines, testing procedures, and data analysis and acceptance. A review of the content of this latest revision will be presented along with a description of how CMH-17, Volume 5 could be used by the FAA (Federal Aviation Administration) and others in the future.

characterization↗
NASA NTRS2006

The TPS Advanced Development Project for CEV

The CEV TPS Advanced Development Project (ADP) is a NASA in-house activity for providing two heatshield preliminary designs (a Lunar direct return as well as a LEO only return) for the CEV, including the TPS, the carrier structure, the interfaces and the attachments. The project s primary objective is the development of a single heatshield preliminary design that meets both Lunar direct return and LEO return requirements. The effort to develop the Lunar direct return capable heatshield is considered a high risk item for the NASA CEV development effort due to the low TRL (approx. 4) of the candidate TPS materials. By initiating the TPS ADP early in the development cycle, the intent is to use materials analysis and testing in combination with manufacturing demonstrations to reduce the programmatic risk of using advanced TPS technologies in the critical path for CEV. Due to the technical and schedule risks associated a Lunar return heatshield, the ADP will pursue a parallel path design approach, whereby a back-up TPS/heatshield design that only meets LEO return requirements is also developed. The TPS materials and carrier structure design concept selections will be based on testing, analysis, design and evaluation of scalability and manufacturing performed under the ADP. At the TPS PDR, the preferred programmatic strategy is to transfer the continued (detailed) design, development, testing and evaluation (DDT&E) of both the Lunar direct and LEO return designs to a government/prime contractor coordinated sub-system design team. The CEV prime contractor would have responsibility for the continued heatshield sub-system development. Continued government participation would include analysis, testing and evaluation as well as decision authority at TPS Final System Decision (FSD) (choosing between the primary and back-up heatshields) occurring between TPS PDR and TPS Critical Design Review (CDR). After TPS FSD the prime CEV contractor will complete the detailed design, certification testing, procurement, and integration of the CEV TPS.

Reuther, James↗
NASA NTRS2015

Update on CMH-17 Volume 5: Ceramic Matrix Composites

CMC components are projected to enter service in commercial aircraft in 2016. A wide range of issues must be addressed prior to certification of this hardware. The Composite Materials Handbook-17, Volume 5 on ceramic matrix composites is being revised to support FAA certification of CMCs for hot structure and other elevated temperature applications. The handbook supports the development and use of CMCs through publishing and maintaining proven, reliable engineering information and standards that have been thoroughly reviewed. Volume 5 will contain detailed sections describing CMC materials processing, design analysis guidelines, testing procedures, and data analysis and acceptance. A review of the status of and plans for two of these areas, which are being addressed by the M and P Working Group and the Testing Working Group, will be presented along with a timeline for the preparation of CMH-17, Volume 5.

design↗
NASA NTRS2018

NASA ACC High Energy Dynamic Impact Methodology and Outcomes

For High Energy Dynamic Impact (HEDI) events, testing to evaluate the structural response of primary aircraft structure for design and certification is both expensive and time consuming. This paper discusses current work seeking to assess, develop, and validate appropriate analytical models that accurately predict physical response, damage, and failure modes for large scale composite structures in HEDI events. Four state-of-the-art Progressive Damage Analysis (PDA) methods were employed for this phased project: LS-DYNA MAT162, LS-DYNA MAT261, Smoothed Particle Galerkin (SPG), and EMU Peridynamics. Multiple material systems were considered, namely T700/5208 textile-infusion triaxial braid, T800/AMD-825 textile-infusion triaxial braid, IM7/8552 uni-directional tape, and SPG 196-PW/8552 plain-weave fabric. Extensive ballistic impact testing was performed to support this activity and measured results were compared to predictive models for assessment using panel delamination, panel displacement, force at the load cells, and threshold velocity as measures. Ultimately, the work under this activity provided significant progress in advancing the state-of-the-art in the use of PDA for HEDI events. Each material model had favorable performance comparing to test in some parameters and needed improvement in others. With the lessons learned from this activity, significant progress was made in the ability to predict panel behavior for a more general case beyond the flat panel in a ballistic impact event. Subsequent Phase II of the NASA ACC HEDI effort will continue to build on the coupon testing, flat panel ballistic impact testing, and analysis performed to-date with application of the PDA methods for intended material selections to test articles with greater complexity of configuration, curvature, and scale. It is not the intention of this paper to present a full set of data, but rather to give an overview of the NASA HEDI effort and show a small representative subset of the test and analysis results.

Hunziker, Kenneth J.↗