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Results for “equipment reliability”

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 145 records · Page 8
All sourcesNASA NTRSDOE OSTI
NASA NTRS1973

Study of blood flow sensing with microwave radiometry

A study and experimental investigation has been performed to determine the feasibility of measuring regional blood flow and volume in man by means of microwave radiometry. An indication was expected of regional blood flow from measurement of surface and subsurface temperatures with a sensitive radiometer. Following theoretical modeling of biological tissue, to determine the optimum operating frequency for adequate sensing depth, a sensitive microwave radiometer was designed for operation at 793 MHz. A temperature sensitivity of of 0.06 K rms was realized in this equipment. Measurements performed on phantom tissue models, consisting of beef fat and lean beefsteak showed that the radiometer was capable of sensing temperatures from a depth between 3.8 and 5.1 cm. Radiometric and thermodynamic temperature measurements were also performed on the hind thighs of large dogs. These showed that the radiometer could sense subsurface temperatures from a depth of, at least, 1.3 cm. Delays caused by externally-generated RF interference, coupled with the lack of reliable blood flow measurement equipment, prevented correlation of radiometer readings with reginal blood flow. For the same reasons, it was not possible to extend the radiometric observations to human subjects.

Porter, R. A.↗
NASA NTRS1985

Controlling Solar-Power Systems With Distributed Processors

System undergoing development uses distributed microprocessors to monitor and control photovoltaic power system. Equipment increases life expectancy and reliability of power system and decreases costs. Adapted to vehicular, residential, and commercial solar and nonsolar power systems. Equipment especially desirable in systems with overall power levels above few kilowatts.

Imamura, M. S.↗
DOE OSTI2024

Advanced HVAC Humidity Control for Hot-Humid Climates

During this project we develop and validate a cost-effective, integrated control solution to improve humidity control and comfort for energy-efficient homes in hot-humid climates. This study focuses on developing a strategy that is effective, field tested, and practical for builders to install with minimal disruption to standard practices. A successful solution would simplify the transition to high-performance humidity control and be the basis for design and installation guidance. By relying on the central system as a starting point, the strategy employed minimizes system complexity and cost for builders, while improving comfort and operating cost for homeowners. The solution strategy was to coordinate the cooling, dehumidification, and ventilation functions of central, ducted HVAC systems to better control indoor humidity, improve occupant thermal comfort, and capture energy savings. The primary strategic goals were to: (1) optimize dehumidification by the central air-conditioning system, particularly during part-load conditions, using conventional equipment with modified control settings and lower system airflows; (2) maximize ventilation during heating/cooling on-cycles, to “bank” and condition outdoor ventilation air, and minimize ventilation during off-cycles; (3) quantify the effectiveness and energy impact of the dehumidification and ventilation strategies, while identifying a metric that would be useful to evaluate latent effectiveness. For the test houses in our study, located in Richmond Hill, Georgia; Houston, Texas; and Monroe, Louisiana we observed: (1) the indoor humidity did not exceed 60% RH during the monitored cooling season for 99% of the time in Richmond Hill, 96% of the time in Houston, and 90% of the time in Monroe; (2) the dehumidification strategy improved the steady-state latent capacity of the HVAC system at design conditions by 16% to 49% at the Houston test house and by 28% to 71% at the Monroe test house, depending on which mode the system was operating in; and (3) the good results at the test houses were primarily due to the amount of time the air-conditioning system operated in ramping or dehumidification modes, or both, particularly during the early cooling season. This study demonstrates that air conditioners or heat pumps with a single-stage compressor can provide good humidity control without the need for a two-stage or variable-stage compressor system. The airflow and control settings for ramping and dehumidification modes are critical to control indoor humidity in hot-humid climates, particularly during part-load and shoulder season conditions. The dehumidification strategy used in this study did not jeopardize the mechanical reliability of the cooling equipment. The strategies used in this study are applicable across various equipment brands, models, and efficiency levels, and also applicable to a broad range of homes in hot-humid climates. Results will vary by specific equipment, location, and house configuration and construction.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗
NASA NTRS1978

Predicting Cost/Reliability/Maintainability of Advanced General Aviation Avionics Equipment

A methodology is provided for assisting NASA in estimating the cost, reliability, and maintenance (CRM) requirements for general avionics equipment operating in the 1980's. Practical problems of predicting these factors are examined. The usefulness and short comings of different approaches for modeling coast and reliability estimates are discussed together with special problems caused by the lack of historical data on the cost of maintaining general aviation avionics. Suggestions are offered on how NASA might proceed in assessing cost reliability CRM implications in the absence of reliable generalized predictive models.

Davis, M. R.↗
DOE OSTI2023

Nuclear explosion monitoring network design considerations

Design of an efficient monitoring network requires information on the type and size of releases to be detected, the accuracy and reliability of the measuring equipment, and the desired network performance. This work provides a scientific basis for optimizing or minimizing networks of 133 Xe samplers to achieve a desired performance level for different levels of release. The approach of this work varies the density of sampling locations to find optimal location subsets, and to explore the properties of variations of those subsets – how crucial is a specific subset; are substitutions problematic? The choice of possible station locations is arbitrary but constrained to some extent by the location of islands, land masses, difficult topography (mountains, etc.) and the places where infrastructure exists to run and support a sampler. Performance is evaluated using hypothetical releases and atmospheric transport models that cover an entire year.

98 NUCLEAR DISARMAMENT, SAFEGUARDS, AND PHYSICAL P↗
DOE OSTI2023

SEEMS: A Single Event Effects and Muon Spectroscopy facility at the Spallation Neutron Source

This study outlines a concept that would leverage the existing proton accelerator at the Spallation Neutron Source (SNS) of Oak Ridge National Laboratory to enable transformative science via one world-class facility serving two missions: Single Event Effects (SEE) and Muon Spectroscopy (μSR). The μSR portion would deliver the world’s highest flux and highest resolution pulsed muon beams for material characterization purposes, with precision and capabilities well beyond comparable facilities. The SEE capabilities deliver neutron, proton, and muon beams for aerospace industries that are facing an impending challenge to certify equipment for safe and reliable behavior under bombardment from atmospheric radiation originating from cosmic and solar rays. With negligible impact on the primary neutron scattering mission of the SNS, the proposed facility will have enormous benefits for both science and industry. Herein, we have designated this facility “SEEMS.”

47 OTHER INSTRUMENTATION↗
DOE OSTI2022

Networked Microgrid Cybersecurity Architecture Design Guide: A New Jersey TRANSITGRID Use Case

Microgrids require reliable communication systems for equipment control, power delivery optimization, and operational visibility. To maintain secure communications, Microgrid Operational Technology (OT) networks must be defensible and cyber-resilient. The communication network must be carefully architected with appropriate cyber-hardening technologies to provide security defenders the data, analytics, and response capabilities to quickly mitigate malicious and accidental cyberattacks. In this work, we outline several best practices and technologies that can support microgrid operations (e.g., intrusion detection and monitoring systems, response tools, etc.). Then we apply these recommendations to the New Jersey TRANSITGRID use case to demonstrate how they would be deployed in practice.

24 POWER TRANSMISSION AND DISTRIBUTION↗
DOE OSTI2025

Propulsion System Hybridization and Electrification and Energy Recovery of the Hydraulic System for a Diesel-Powered Off-Road Carry/Lift Machine Final Technical Report (FTR)

Historically, heavy-duty off-road equipment has prioritized performance, reliability, and cost, with limited emphasis on efficiency. While increasing carbon dioxide (CO 2 ) regulations have driven a focused effort for efficiency in on-road vehicles, off-road machines have remained largely overlooked, leaving significant opportunities for efficiency improvements and emissions reductions. To address this overlooked industry, Michigan Technological University’s Advanced Power Systems Research Center (APS LABS) worked with Pettibone to determine a unique electrified architecture for Pettibone’s heavy-duty off-road material handler, the Cary-Lift 204i, with a goal of 20% fuel savings. The base Cary-Lift uses a diesel engine with no electrification.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
NASA NTRS1965

Apollo checkout equipment.

Schematic and flow diagrams showing uplink and downlink of Apollo spacecraft automatic checkout equipment

APOLLO SPACECRAFT↗
NASA NTRS1972

Modularized instrument system for turbojet engine test facilities

A modular instrument system is being developed to handle the many data channels encountered in turbojet engine testing. Each module contains a group of transducers and all the signal conditioning multiplexing, and digitizing electronics necessary for direct interface with a digital computer. The digital interface within each module is the same for all modules; in addition, each module provides a controlled environment for its contents. A minicomputer in the control room gathers the data, performs on-line calculation and display, and interfaces with a shared recording and computing system. The advantages of this system are: (1) reduced manpower for system installation, setup, and checkout; (2) standardized equipment interfaces; (3) increased reliability through automatic system testing and minimization of manual adjustments; and (4) reduced cost through minimization of wiring and simplification of control room display.

Nieberding, W. C.↗
NASA NTRS1972

The interplanetary Pioneers. Volume 2: System design and development

The Pioneer systems, subsystems, and ground support activities are described. Details are given on the launch trajectory and solar orbit plans, spacecraft design approach and evolution, scientific instrument, test and ground support equipment, Delta launch vehicle, tracking and communication, and data processing equipment. Pioneer specifications, and reliability and quality assurance are also included.

Corliss, W. R.↗
NASA NTRS1973

Design guidelines for use of adhesives in hybrid microcircuits

Although it is generally accepted that the use of adhesives in the assembly of hybrid microcircuits offers advantages over other bonding methods, there currently does not exist a set of guidelines for the selection of adhesives which will insure that hybrid microcircuits assembled with them will meet the long use-life, high-reliability requirements of electronic equipment for space applications. This study was directed to the identification of the properties of electrically insulative adhesives that potentially could cause problems in such an application, and to the development of evaluation tests to quantify these properties and thus form the basis for establishing suitable guidelines and, ultimately, specifications. Bond strength, outgassing after cure, and corrosivity were selected for detailed attention since they are considered to be especially critical. Introductory discussion includes enumeration and brief comments on the properties of adhesives considered to be important for the proposed application, a general review of polymeric types of adhesives, and identification of the major types of adhesives commercially available and specifically designed for microelectronic use. The specific tests developed to evaluate bond strength, outgassing after cure, and corrosivity are discussed in detail, and comparative results obtained for selected adhesives representative of the major types are given.

Caruso, S. V.↗