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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 361 records · Page 20
All sourcesNASA NTRSDOE OSTI
NASA NTRS2011

NASA Tech Briefs, February 2011

Topics covered include: Multi-Segment Radius Measurement Using an Absolute Distance Meter Through a Null Assembly; Fiber-Optic Magnetic-Field-Strength Measurement System for Lightning Detection; Photocatalytic Active Radiation Measurements and Use; Computer Generated Hologram System for Wavefront Measurement System Calibration; Non-Contact Thermal Properties Measurement with Low-Power Laser and IR Camera System; SpaceCube 2.0: An Advanced Hybrid Onboard Data Processor; CMOS Imager Has Better Cross-Talk and Full-Well Performance; High-Performance Wireless Telemetry; Telemetry-Based Ranging; JWST Wavefront Control Toolbox; Java Image I/O for VICAR, PDS, and ISIS; X-Band Acquisition Aid Software; Antimicrobial-Coated Granules for Disinfecting Water; Range 7 Scanner Integration with PaR Robot Scanning System; Methods of Antimicrobial Coating of Diverse Materials; High-Operating-Temperature Barrier Infrared Detector with Tailorable Cutoff Wavelength; A Model of Reduced Kinetics for Alkane Oxidation Using Constituents and Species for N-Heptane; Thermally Conductive Tape Based on Carbon Nanotube Arrays; Two Catalysts for Selective Oxidation of Contaminant Gases; Nanoscale Metal Oxide Semiconductors for Gas Sensing; Lightweight, Ultra-High-Temperature, CMC-Lined Carbon/Carbon Structures; Sample Acquisition and Handling System from a Remote Platform; Improved Rare-Earth Emitter Hollow Cathode; High-Temperature Smart Structures for Engine Noise Reduction and Performance Enhancement; Cryogenic Scan Mechanism for Fourier Transform Spectrometer; Piezoelectric Rotary Tube Motor; Thermoelectric Energy Conversion Technology for High-Altitude Airships; Combustor Computations for CO2-Neutral Aviation; Use of Dynamic Distortion to Predict and Alleviate Loss of Control; Cycle Time Reduction in Trapped Mercury Ion Atomic Frequency Standards; and A (201)Hg+ Comagnetometer for (199)Hg+ Trapped Ion Space Atomic Clocks.

Source record↗
DOE OSTI2022

Machine Learning-based Cyber-Physical Anomaly Detection in Wide Area Voltage Control Systems

Wide-area voltage control systems (WAVCS) are widely deployed in power grid to improve the voltage stability in transmission system using Flexible AC Transmission System (FACTS) devices. The WAVCS relies on wide-area measurement and control signals for closed-loop control of FACTS devices to improve the transient voltage stability in power grid in real-time. Since the WAVCS utilizes a cyber-layer communication during its normal operation, they are susceptible to cyber attacks from adversaries which can lead to a voltage collapse if the attacks go undetected and unmitigated. This paper proposes a supervised machine learning (ML)-based anomaly detection algorithm for detecting various stealthy cyber attacks in the context of WAVCS cybersecurity. In particular, a fuzzy logic-based wide-area controller, as proposed by the Bonneville Power Administration (BPA), is implemented on the Kundur’s four machine two-area system that is integrated with a static var compensator (SVC) to improve voltage profile on sensitive buses. Later, different types of data integrity attacks, including pulse and ramp attacks, are considered on the wide-area measurement and control signals to analyze the performance of the proposed anomaly detector. Our experimental evaluation shows a promising performance with a high true-positive rate (more than 99%) and low false-negative rate (less than 1%) while exhibiting a small prediction time.

24 POWER TRANSMISSION AND DISTRIBUTION↗
DOE OSTI2023

Thermodynamic stability of xenon-doped liquid argon detectors

Liquid argon detectors are employed in a wide variety of nuclear and particle physics experiments. The addition of small quantities of xenon to argon modifies its scintillation, ionization, and electroluminescence properties and can improve its performance as a detection medium. However, a liquid argon-xenon mixture can develop instabilities, especially in systems that require phase transitions or that utilize high xenon concentrations. In this work, we analyze the causes of these instabilities and describe a small (liter-scale) apparatus with a unique cryogenic circuit specifically designed to handle argon-xenon mixtures. The system is capable of condensing argon gas mixed with $\mathscr{O}$ (1%) xenon by volume and maintains a stable liquid mixture near the xenon saturation limit while actively circulating it in the gas phase. We also demonstrate control over instabilities that develop when the detector condition is allowed to deviate from optimized settings. This progress enables future liquid argon detectors to benefit from the effects of high concentrations of xenon doping, such as more efficient detection of low-energy ionization signals. In conclusion, this work also develops tools to study and mitigate instabilities in large argon detectors that use low concentration xenon doping.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗
DOE OSTI2023

Verification of Spent Fuel Inside Dry Storage Casks by Cask Top Fast Neutron Mapping (FY2023 Mid-Year Report)

This project is developing a prototype scanner array verification system for detection of missing fuel assemblies in spent-fuel storage casks. The prototype consists of six fast-neutron scintillator detectors mounted to a linear actuator frame that is placed on the top of a spent fuel cask to scan across all fuel assembly positions. The scanner array was assembled and tested at LLNL in FY2022. A field test schedule has been requested at the Idaho National Laboratory (INL) Cask Farm site for FY2023. Note that the Cask Farm contractor determines this scheduling and not INL directly. Further system automation will be designed and implemented with the goal of obtaining a level of system operation that meets IAEA needs. This includes integration of the scanner array and data-acquisition control software into a single interface for operator use. In addition, commercial operators and the IAEA may have special requirements for portability, shipping, lifting, and installation. Prior to the Field Test at INL, the system will be operated at LLNL to exercise lifting procedure and linear actuators, monitor stability of detector energy and pulse-shape discrimination calibration, and test system software integration efforts. Following the Field Test, we will present results and discuss the technology with the IAEA. We will incorporate additional improvements to the system based on lessons learned from the field test and feedback from the IAEA. If successful, the technology can be transferred to the IAEA or other stakeholders for assessment.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗
NASA NTRS2023

Closed Environment Air Revitalization System Based on Metal Organic Framework Adsorbents

This project utilized a systems engineering methodology to develop a vacuum swing adsorption system with full Labview automated control. The project was successful and provided students with an introduction to systems engineering and air revitalization. Specifically, two stainless steel adsorption beds were custom designed and manufactured and a sequence of computer controlled valves were used to deliver CO 2 laden, humid air, to the adsorbent where the CO 2 was removed from the air stream. Runs were completed using 13X zeolite and bed timing and switching was controlled by the computer based on the data output of a CO 2 detector. Adsorption runs using the MOF have not been completed upon the writing of this report; however, the MOF material is currently being synthesized and the runs will be completed upon receipt of the material. A follow up meeting with NASA has been tentatively planned to discuss the output of these experiments. Consistent with systems engineering practice, an end of project assessment of the class was conducted with the students and several items were realized. Specifically, the short period of performance of this grant makes it necessary to maintain a narrowly focused scope on the project such that multiple experiments after systems development (T&E) need to be limited to ensure timely completion of the proposed tasks. Also, procurement of parts may need to be moved forward in time to allow for delivery delays, and it may be necessary to request SDR, PDR, and CDR dates from NASA that are ahead of the NASA anticipated schedule. These types of lessons provided valuable to both the PI and the students and ultimately illustrate the necessity of proper systems engineering schedule risk assessment. The class met the objectives of the project and provided an introduction to systems engineering to undergraduate students. As a metric of that success, the lead engineer of the undergraduate design team acquired a job with an aerospace defense contractor, which he attributed to his knowledge of systems engineering concepts that were acquired via the X-Hab class.

T. Grant Glover↗
NASA NTRS2006

Semiautonomous Avionics-and-Sensors System for a UAV

Unmanned Aerial Vehicles (UAVs) autonomous or remotely controlled pilotless aircraft have been recently thrust into the spotlight for military applications, for homeland security, and as test beds for research. In addition to these functions, there are many space applications in which lightweight, inexpensive, small UAVS can be used e.g., to determine the chemical composition and other qualities of the atmospheres of remote planets. Moreover, on Earth, such UAVs can be used to obtain information about weather in various regions; in particular, they can be used to analyze wide-band acoustic signals to aid in determining the complex dynamics of movement of hurricanes. The Advanced Sensors and Electronics group at Langley Research Center has developed an inexpensive, small, integrated avionics-and-sensors system to be installed in a UAV that serves two purposes. The first purpose is to provide flight data to an AI (Artificial Intelligence) controller as part of an autonomous flight-control system. The second purpose is to store data from a subsystem of distributed MEMS (microelectromechanical systems) sensors. Examples of these MEMS sensors include humidity, temperature, and acoustic sensors, plus chemical sensors for detecting various vapors and other gases in the environment. The critical sensors used for flight control are a differential- pressure sensor that is part of an apparatus for determining airspeed, an absolute-pressure sensor for determining altitude, three orthogonal accelerometers for determining tilt and acceleration, and three orthogonal angular-rate detectors (gyroscopes). By using these eight sensors, it is possible to determine the orientation, height, speed, and rates of roll, pitch, and yaw of the UAV. This avionics-and-sensors system is shown in the figure. During the last few years, there has been rapid growth and advancement in the technological disciplines of MEMS, of onboard artificial-intelligence systems, and of smaller, faster, and smarter wireless telemetry systems. The major attraction of MEMS lies in orders-of-magnitude reductions of power requirements relative to traditional electronic components that perform equivalent functions. In addition, the compactness of MEMS, relative to functionally equivalent traditional electronics systems, makes MEMS attractive for UAV applications. Recent advances in MEMS have made it possible to produce pressure, acceleration, humidity, and temperature sensors having masses in subgram range and possessing sensitivities and accuracies comparable to those of larger devices.

Shams, Qamar↗
NASA NTRS1977

Stabilized Nd:YAG laser output

Stabilization system consists of feedback-loop-controlled piezoelectric crystal to one of the reflectors to vary optical path length within laser cavity. Average second harmonic of fundamental 1.06 micrometer laser radiation is detected by integrating detector.

Osmundson, J.↗
NASA NTRS1979

A 1.2 meter balloon-borne telescope for a submillimeter wave sky survey

A balloon-borne, 1.2 meter Cassegrain telescope designed for diffraction-limited imagery at 100 microns is being developed for a survey of the Galactic plane at submillimeter wavelengths. The telescope pointing system is servocontrolled using a gyroscope for the primary stabilization reference. Extensive use is made of microprocessors for flight sequencing, pointing control and stabilization, and telemetry formatting. A description of the telescope, helium-cooled detectors, and the orientation subsystems are presented together with a brief discussion of the proposed astronomical observations.

Silverberg, R. F.↗
NASA NTRS1990

Cockpit display of hazardous wind shear information

Information on cockpit display of wind shear information is given in viewgraph form. Based on the current status of windshear sensors and candidate data dissemination systems, the near-term capabilities for windshear avoidance will most likely include: (1) Ground-based detection: TDWR (Terminal Doppler Weather Radar), LLWAS (Low-Level Windshear Alert System), Automated PIREPS; (2) Ground-Air datalinks: Air traffic control voice channels, Mode-S digital datalink, ACARS alphanumeric datalink. The possible datapaths for integration of these systems are illustrated in a diagram. In the future, airborne windshear detection systems such as lidars, passive IR detectors, or airborne Doppler radars may also become available. Possible future datalinks include satellite downlink and specialized en route weather channels.

Wanke, Craig↗
NASA NTRS1992

The 2nd phase of the LEANDRE program: Water-vapor DIAL measurement

As a follow-on of the backscattered lidar, a differential absorption lidar (LEANDRE 2) is now being developed as part of the LEANDRE program for airborne meteorological studies. The primary measurement objective of LEANDRE 2 is water vapor. Pressure and temperature measurements are aimed at a second stage. The goals are to obtain a horizontal resolution of a few hundred meters for a vertical resolution of less than a hundred meters, with an absolute accuracy of 10 percent for humidity measurement. As compatibility is an important feature between the 2 first phases of LEANDRE, most of the LEANDRE 1 sub-system will be used and adapted for LEANDRE 2. For example, detection electronics, central computer, detectors and telescope will be the same. However, important modifications have to be done on the laser source, and spectral control has to be added. Most of the work is thus devoted to those developments, and the status is presented here.

Quaglia, P.↗
NASA NTRSDate not supplied

The Experiment for Cryogenic Large-Aperture Intensity Mapping (EXCLAIM)

The EXperiment for Cryogenic Large-Aperture Intensity Mapping (EXCLAIM) is a high-altitude balloon telescope designed to deepen our understanding of star formation in a cosmological context, shedding light on why the star formation rate declines and breaks away from the cosmological evolution of dark matter for redshifts z>2 [1]. EXCLAIM will operate at 420–540 GHz with a spectral resolution of R=512 to measure the integrated line emission from galaxies and the intergalactic medium (IGM), in particular CO and [CII] line emissions from the nearby universe out to redshifts of z~3.5. This approach is known as Intensity Mapping (IM), which provides efficient access to large cosmological volumes and redshifts with sensitivity limited by detector noise or photon background, while requiring modest apertures. The instrument will employ an array of six superconducting integrated grating-analog spectrometers (µ-Spec) with superconducting microwave kinetic inductance detectors (KIDs) in an all-cryogenic telescope (1.7 K) to achieve near background-limited sensitivity. Here, we present an overview of the EXCLAIM instrument and status, with emphasis on the Attitude Determination & Control System (ADCS) and the thermal system.

Giuseppe Cataldo↗
DOE OSTI2026

Development of a Test-Bed for Testing and Refining EarthEn’s Supercritical CO 2 Based Energy Storage System

EarthEn’s energy storage concept leverages supercritical carbon dioxide (sCO 2 ) as a working fluid and relies on compact, high-performance components operating at elevated pressures and temperatures. To accelerate component development and reduce technical risk prior to larger-scale demonstrations, Oak Ridge National Laboratory (ORNL) developed a 100 kW-scale sCO 2 test-bed under a Cooperative Research and Development Agreement with EarthEn (CRADA NO. NFE-24-10050). The objective of the work was to design and construct a flexible experimental facility capable of reproducing key thermodynamic state points and heat-transfer conditions relevant to EarthEn’s thermal energy storage (TES) cycle, with particular emphasis on enabling development and evaluation of next-generation heat exchangers and TES concepts. The test-bed consists of a closed-loop sCO 2 circulation system housed within an open-topped enclosure. In its as-installed configuration, dense-phase sCO 2 is recirculated through a printed circuit recuperator, an electrically heated section, a throttling device used to simulate turbine expansion, and a water-cooled printed circuit heat exchanger that rejects heat to the building chilled-water system before returning to the pump. The pump is driven by a variable frequency drive, enabling controlled adjustment of flow and operating point. A comprehensive instrumentation suite was integrated to support both safe operation and high-quality data collection. Installed sensors include Coriolis flow meters for sCO 2 flow rate and density, resistance temperature detectors and thermocouples distributed throughout the loop (including the heated section and key heat exchanger ports), and pressure transducers for absolute and differential pressure measurements. The facility was designed to support high-pressure (19 MPa nominal) and high-temperature (575°C nominal) operation with credited overpressure protection provided by a rupture disk. Nominal operating conditions were selected to support 100 kW-class testing while maintaining flexibility for non-heated and heated shakedown, control development, and future integration of advanced TES test sections. In parallel with facility development, a system-level thermal-hydraulic model was created using Modelica-based tools to support component sizing, anticipate performance over targeted test conditions, and establish a framework for future model calibration against experimental data. At the conclusion of the project performance period, the facility was in final assembly, and the pressure boundary was nearly completed. However, several practical challenges associated with high-pressure/high-temperature systems and specialized component procurement impacted schedule and prevented initial pump-driven operation and full commissioning within the available resources. This report documents the as-built design, operating capabilities, and instrumentation, and it summarizes key lessons learned related to heater fabrication and testing, first-of-a-kind assembly factors, specialty flange supply constraints, and fill pump corrective actions. Finally, it outlines a phased plan for future commissioning and experimental campaigns, including control and instrumentation shakedown, heater characterization, model calibration, and testing at state points representative of EarthEn’s TES cycle.

25 ENERGY STORAGE↗
NASA NTRS1974

Development of a long wavelength spectrometer for the 24-channel multispectral scanner: Instructions for installation, start-up, and adjustment

The basic information is presented, which is required for start-up and operation of two long-wavelength focal-plane and cooler assemblies, including the amplifiers and temperature control systems. The focal plane systems, referred to as the long wavelength spectrometer (LWS) were developed for direct replacement of Arrays 3 and 4 into the multispectral scanner presently being operated by the NASA Manned Spacecraft Center Facility, and Laboratory Support Branch. The equipment is comprised of two major sub-assemblies: Array 3 with three indium antimonide detector channels and Array 4 with seven mercury doped Germanium detector channels. Each array is mounted on a cryogenic cooler and includes the vacuum housings, mounting hardware (x, y, z translation and rotation stages) and detector signal conditioning, temperature control and monitoring electronics. The two arrays were designed to operate independently and do not share common equipment (viz power supplies, housings, mounts, etc.).

Source record↗
NASA NTRS2003

SWIFT BAT Loop Heat Pipe Thermal System Characteristics and Ground/Flight Operation Procedure

The SWIFT Burst Alert Telescope (BAT) Detector Array has a total power dissipation of 208 W. To meet the stringent temperature gradient and thermal stability requirements in the normal operational mode, and heater power budget in both the normal operational and safehold modes, the Detector Array is thermally well coupled to eight constant conductance heat pipes (CCHPs) embedded in the Detector Array Plate (DAP), and two loop heat pipes (LHPs) transport heat fiom the CCHPs to a radiator. The CCHPs have ammonia as the working fluid and the LHPs have propylene as the working fluid. Precision heater controllers, which have adjustable set points in flight, are used to control the LHP compensation chamber and Detector Array XA1 ASIC temperatures. The radiator has the AZ-Tek AZW-LA-II low-alpha white paint as the thermal coating and is located on the anti-sun side of the spacecraft. This paper presents the characteristics, ground operation and flight operation procedures of the LHP thermal system.

Choi, Michael K.↗
NASA NTRS1978

Temperature control analysis and flight results for the Viking Orbiter 1975 Mars atmospheric water detection instrument

The Mars atmospheric water detector (MAWD) instrument required a temperature of -70 C at the detector. The monochromator housing required +20 C + or - 1 C. This instrument was located on the scan platform, and slewed across two solar panels. The thermal design for the detector was an open flat plate radiator thermally isolated on four 1-in. tubes, with a flexible strap to the detector. MAWD radiator view factors and heat loads from the spacecraft were determined for the Lander on and off, for all angular positions of the scan platform. Subsystem and system tests were performed using the 25-ft diameter solar simulator. In-flight results have shown no anomalies, and no degradation has been observed. Servo-controlled heaters are used to control the temperature.

Kavanagh, H. M.↗
DOE OSTI2020

The CLAS12 Data Acquisition System

The CLAS12 Data Acquisition System was designed and built as part of the CLAS12 detector project in Hall B at Jefferson Laboratory. This article contains a full description of the system, including requirements, design, hardware, and software descriptions, as well as the achieved performance. The associated computing, network, and slow controls systems are also described.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗
NASA NTRS1977

Nuclear Science Symposium, 23rd, Scintillation and Semiconductor Counter Symposium, 15th, and Nuclear Power Systems Symposium, 8th, New Orleans, La., October 20-22, 1976, Proceedings

The volume includes papers on semiconductor radiation detectors of various types, components of radiation detection and dosimetric systems, digital and microprocessor equipment in nuclear industry and science, and a wide variety of applications of nuclear radiation detectors. Semiconductor detectors of X-rays, gamma radiation, heavy ions, neutrons, and other nuclear particles, plastic scintillator arrays, drift chambers, spark wire chambers, and radiation dosimeter systems are reported on. Digital and analog conversion systems, digital data and control systems, microprocessors, and their uses in scientific research and nuclear power plants are discussed. Large-area imaging and biomedical nucleonic instrumentation, nuclear power plant safeguards, reactor instrumentation, nuclear power plant instrumentation, space instrumentation, and environmental instrumentation are dealt with. Individual items are announced in this issue.

Wagner, L. J.↗