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Results for “source configuration”

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 181 records · Page 10

All sources NASA NTRS DOE OSTI

NASA NTRS1996

Free-Roller Versus Fixed-Roller Fixtures in Flexure Testing of Advanced Ceramic Materials

The error associated with strength measurements made with fixed-roller and V-grooved roller figures was studied with a variety of roller and figure material combinations. Both the fixed-roller and the V-grooved fixtures yielded an error in stress of about 4 to 7%. They also exhibited an appreciable amount of load strain hysteresis. Dynamic fatigue testing of 96 wt.% alumina verified the error: the fatigue strength was overestimated by 7 to 9% for the fixed roller configuration. The source of error is exclusively attributed to friction between the rollers and the specimen surface, as verified by previous investigators.

Salem, Jonathan A.↗

NASA NTRS2001

Integrated Power Source Grant

Traditional spacecraft power systems incorporate a solar array energy source, an energy storage element (battery), and battery charge control and bus voltage regulation electronics to provide continuous electrical power for spacecraft systems and instruments. Dedicated power conditioning components provide limited fault isolation between systems and instruments, while a centralized power-switching unit provides spacecraft load control. Battery undervoltage conditions are detected by the spacecraft processor, which removes fault conditions and non-critical loads before permanent battery damage can occur. Cost effective operation of a micro-sat constellation requires a fault tolerant spacecraft architecture that minimizes on-orbit operational costs by permitting autonomous reconfiguration in response to unexpected fault conditions. A new micro-sat power system architecture that enhances spacecraft fault tolerance and improves power system survivability by continuously managing the battery charge and discharge processes on a cell-by-cell basis has been developed. This architecture is based on the Integrated Power Source (US patent 5644207), which integrates dual junction solar cells, Lithium Ion battery cells, and processor based charge control electronics into a structural panel that can be deployed or used to form a portion of the outer shell of a micro-spacecraft. The first generation Integrated Power Source is configured as a one inch thick panel in which prismatic Lithium Ion battery cells are arranged in a 3x7 matrix (26VDC) and a 3x1 matrix (3.7VDC) to provide the required output voltages and load currents. A multi-layer structure holds the battery cells, as well as the thermal insulators that are necessary to protect the Lithium Ion battery cells from the extreme temperatures of the solar cell layer. Independent thermal radiators, located on the back of the panel, are dedicated to the solar cell array, the electronics, and the battery cell array. In deployed panel applications, these radiators maintain the battery cells in an appropriate operational temperature range.

Source record↗

NASA NTRS2004

James Webb Space Telescope (JWST) Integrated Science Instrument Module (ISIM) Cryogenic Component Test Facility

Contents include the following: James Webb Space Telescope/Integrated Science Instrument Module (JWST/ISIM) Overview. ISIM Thermal Verification Requirements. Emittance Test Objectives. Cryochamber Design Requirements. Cryochamber Construction. Emittance Test Sample Selection and Configuration. Error Sources and Error Mitigation. Cryochamber Operation. Cryochamber and Emittance Sample Test Results.

Packard, Edward A.↗

NASA NTRS2013

Auralization of Hybrid Wing Body Aircraft Flyover Noise from System Noise Predictions

System noise assessments of a state-of-the-art reference aircraft (similar to a Boeing 777-200ER with GE90-like turbofan engines) and several hybrid wing body (HWB) aircraft configurations were recently performed using NASA engine and aircraft system analysis tools. The HWB aircraft were sized to an equivalent mission as the reference aircraft and assessments were performed using measurements of airframe shielding from a series of propulsion airframe aeroacoustic experiments. The focus of this work is to auralize flyover noise from the reference aircraft and the best HWB configuration using source noise predictions and shielding data based largely on the earlier assessments. For each aircraft, three flyover conditions are auralized. These correspond to approach, sideline, and cutback operating states, but flown in straight and level flight trajectories. The auralizations are performed using synthesis and simulation tools developed at NASA. Audio and visual presentations are provided to allow the reader to experience the flyover from the perspective of a listener in the simulated environment.

Rizzi, Stephen A.↗

NASA NTRS2016

Methods of Soft Tissue Emulsification Using a Mechanism of Ultrasonic Atomization Inside Gas or Vapor Cavities and Associated Systems and Devices

The present technology is directed to methods of soft tissue emulsification using a mechanism of ultrasonic atomization inside gas or vapor cavities, and associated systems and devices. In several embodiments, for example, a method of non-invasively treating tissue includes pulsing ultrasound energy from the ultrasound source toward the target site in tissue. The ultrasound source is configured to emit high intensity focused ultrasound (HIFU) waves. The target site comprises a pressure-release interface of a gas or vapor cavity located within the tissue. The method continues by generating shock waves in the tissue to induce a lesion in the tissue at the target site. The method additionally includes characterizing the lesion based on a degree of at least one of a mechanical or thermal ablation of the tissue.

Sapozhnikov, Oleg A.↗

NASA NTRS2024

Thermal Inspection of Low Emissivity Surfaces Using a Pulsed Light Emitting Diodes (PLED) Heat Source

Thermal inspections of a structure typically utilize a flash or quartz lamp heat source located on the same side of an infrared camera. The heat source provides light energy for heating while the infrared camera measures the surface transient temperature response. The inspection can be difficult for low emissivity surfaces for several reasons. First, the high intensity light can reflect off the surface and cause “burn-in” to the camera’s detector. The “burn-in” can take time for the sensors to recover and potentially damage the detector. Secondly, the heat source after pulsing, has a transient cool down component. The cool down component can be reflected and therefore superimposed over the structure’s thermal response which can cause an error (false defect indications) in the inspection. Lastly, the heat source is spectrally broad and therefore while heating, infrared components of the heat source can produce non-uniformity in the measured temperature field. Typically for the inspection of reflective surfaces, paint or other emissivity enhancing coatings are applied before inspection. In this paper, a pulsed light emitting diodes (PLED) heat source is used. The PLED heat source is spectrally narrow, contained within the visible band, and therefore not detectable by the infrared camera. The PLED heat source is configured to reduce any transient cool down components that could produce false defect indications. The PLED thermal inspections are compared to commercially available flash thermography inspections on unpainted aluminum samples with simulated corrosion and additively manufactured Ti-6AL-4V metal specimens.

thermal nondestructive evaluation↗

NASA NTRS2024

Thermal Inspection of Low Emissivity Surfaces Using a Pulsed Light Emitting Diodes (PLED) Heat Source

thermal nondestructive evaluation↗

DOE OSTI2017

Color-tunable lighting devices and methods of use

A lighting device (100) includes a housing (104) enclosing a housing interior (108), a light source (132), a light converter (136), and a color tuning device. The light source is configured for emitting a primary light beam of a primary wavelength (140) through the housing interior. The light converter includes a luminescent material (144) facing the housing interior and configured for emitting secondary light (156, 158) of one or more wavelengths different from the primary wavelength, in response to excitation by the primary light beam. The housing includes a light exit (124) for outputting a combination of primary light and secondary light. The color tuning device is configured for adjusting a position of the primary light beam relative to the luminescent material.

36 MATERIALS SCIENCE↗

DOE OSTI2015

Electrochemical system and method for electropolishing superconductive radio frequency cavities

An electrochemical finishing system for super conducting radio frequency (SCRF) cavities including a low viscosity electrolyte solution that is free of hydrofluoric acid, an electrode in contact with the electrolyte solution, the SCRF cavity being spaced apart from the electrode and in contact with the electrolyte solution and a power source including a first electrical lead electrically coupled to the electrode and a second electrical lead electrically coupled to the cavity, the power source being configured to pass an electric current between the electrode and the workpiece, wherein the electric current includes anodic pulses and cathodic pulses, and wherein the cathodic pulses are interposed between at least some of the anodic pulses. The SCRF cavity may be vertically oriented during the finishing process.

36 MATERIALS SCIENCE↗

DOE OSTI2018

Fuel cell system including sacrificial nickel source

In some examples, solid oxide fuel cell system comprising a solid oxide fuel cell including an anode, an anode conductor layer, a cathode, a cathode conductor layer, and electrolyte, wherein the anode and the anode conductor layer each comprise nickel; and a sacrificial nickel source separate from that of the anode and anode conductor layer, wherein the sacrificial nickel source is configured to reduce the loss or migration of the nickel of the anode and/or the anode current collector in the fuel cell during operation.

30 DIRECT ENERGY CONVERSION↗

DOE OSTI2019

X-ray imaging and chemical analysis of plant roots

A linear x-ray tube having one or more x-ray sources is configured for insertion into the soil in proximity to a root system of a plant for emission of an x-ray beam detected by a linear array of one or more x-ray detectors. The linear x-ray tube and detector array may be inserted into rhizotrons previously inserted into the soil. Various combinations of multiple x-ray tubes and/or detector arrays may be utilized to customize the x-ray imaging of the root system.

Kumar, Nalin↗

DOE OSTI2020

System and method for high efficiency electrochemical desalination

The present disclosure relates to a capacitive deionization (CDI) system for desalinating salt water. The system may have a capacitor formed by spaced apart first and second electrodes, which enable a fluid flow containing salt water to pass either between them or through them. An input electrical power source is configured to generate an electrical forcing signal between the two electrodes. The electrical forcing signal represents a periodic signal including at least one of voltage or current, and which can be represented as a Fourier series. One component of the Fourier series is a constant, and a second component of the Fourier series is a sinusoidal wave of non-zero frequency which has the highest amplitude of the additive components of the Fourier series. The amplitude of the sinusoidal wave component is between 0.85 and 1.25 times the amplitude of the periodic signal.

Hawks, Steven↗

DOE OSTI2022

Combustor with dual pressure premixing nozzles

A combustor may include a combustor liner and flow sleeve. A high pressure air cools an outer surface of the combustor liner via openings in the flow sleeve, creating a lower pressure air in an annulus between the combustor liner and the flow sleeve. A first fuel nozzle is positioned at a primary combustion zone, and a second fuel nozzle is positioned at a secondary combustion zone of the liner. A fuel source is configured to deliver a fuel to the fuel nozzles. The fuel nozzles produce a premixture of high pressure air and the fuel, and produce a mixture of the premixture and the lower pressure air, prior to introducing the mixture to a respective primary or secondary combustion zone of the combustor. The combustor provides improved fuel premixing and is fuel flexible, and reduces pressure drop requirements. The combustor is usable in a can, annular, or segmented annular combustor assembly.

Berry, Jonathan Dwight↗

DOE OSTI2023

Multichannel angular spectrometer

A multichannel angular spectrometer includes an array of fiber pickups having an arcuate arrangement and focused about a sample volume. A broadband light source is configured to illuminate a sample within the sample volume. At least one dispersion element is in optical communication with the array of fiber pickups. An imaging sensor is in optical communication with the array of fiber pickups. The imaging sensor is configured to image the broadband light received by the array of fiber pickups and dispersed by the at least one dispersion element. A processor is in electrical communication with the imaging sensor. The processor has a power supply and computer-readable memory.

47 OTHER INSTRUMENTATION↗

DOE OSTI2023

Systems, method and computer-accessible medium for providing balanced asymmetric interferometry for vibrationally isolated optical scanning probe(s)

An exemplary apparatus can provide radiation to a sample(s), which can include, for example, a radiation source arrangement configured to provide radiation, a beam splitter configured to split the radiation into (i) a first radiation, and (ii) a second radiation. An optical element can also be provided which, in operation, can, e.g., (a) receive the first radiation and the second radiation, (b) reflect the first radiation as a reference radiation, (c) provide the second radiation as illumination for the sample(s), (d) receive a resultant radiation from the sample(s) that can be based on the illumination from the second radiation, and (e) provide the reference radiation and the resultant radiation to be detected and used for interferometric imaging or spectroscopy.

McLeod, Alexander Swinton↗

DOE OSTI2024

Split source drain transistor

Systems, methods, circuits, and devices for providing and using transistors in a physically unclonable function (PUF) circuit. The transistors comprise a split source drain configuration including one or more inflection segments that increase process variations between the transistors such that each transistor generates a unique output signal.

Trujillo, Joshua Joseph↗

DOE OSTI2024

Disinfection system with high throughput and low power requirements

Devices, methods and techniques are disclosed to perform high confidence sterilization of indoor air with low power requirements. In one example aspect, a sterilization device includes a power source, an energy storage coupled to the power source and configured to store electric charges, a set of electrodes arranged in a specified geometry to have a fixed characteristic impedance, and a switch positioned between the energy storage and the set of electrodes. The switch is configured to operate to establish a pulsed electric field on the set of electrodes.

Sampayan, Stephen↗

DOE OSTI2018

Method and system for analyzing gas leak based on machine learning

Embodiments of the present invention provide a system for estimating a location of a gas leak, based on machine learning from forward gas concentration data provided by an analog or scale model including a gas source. The system improves significantly over previous systems by providing high quality, physically accurate forward modeling data inexpensively. During operation, the system configures an aerosol source at a first location to emit a gaseous aerosol. The system then configures a laser source to illuminate the aerosol with a laser sheet. The system may then obtain an image of a reflection of the laser sheet from the aerosol. The system may then analyze the image to quantify a three-dimensional concentration distribution of the aerosol. The system may then estimate, based on solving an inverse problem and an observed second gas concentration, a second location of a second gas source.

03 NATURAL GAS↗