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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 109 records · Page 6
All sourcesNASA NTRSDOE OSTI
NASA NTRS1957

Experimental Investigation of Temperature Feedback Control Systems Applicable to Turbojet-engine Control

Temperature - fuel-flow and temperature-area feedback control systems were investigated as means of controlling tailpipe gas temperature of a turbojet engine during transient operation in the high-speed region. Proportional-plus-integral control was used in both systems, but in the temperature-area control system it was necessary to add nonlinear components to the basic proportional-plus-integral control to provide satisfactory transient response to a desired step increase in temperature. Time integral of temperature-error functions were used as criteria for determining optimum transient response. A description of engine dynamics was obtained from frequency-response data.

ENGINES, TURBOJET↗
DOE OSTI2023

ENYGF 2023 - Design of Temperature-controlled Fuel-salt Irradiation Experiment

Idaho National Laboratory (INL) is developing a Molten salt Research Temperature-controlled Irradiation (MRTI) experimental capsule for the Neutron Radiography (NRAD) reactor. The experiment is envisaged to be versatile and able to host a variety of salt-wall material combinations. The first test is designed to contain actinide-bearing chloride salt, which previously has not been subjected to a neutron field. The main objectives of the experiment are to produce irradiated salt samples for Post Irradiation Examination (PIE), to evaluate salt behavior under irradiation, and to test in-situ sensors/instrumentation. The final design for the experiment completed in 2022, and fabrication of the experiment is underway. The salt is double encapsulated providing insulation and redundancy in the case of leakage. A gas-gap between the inner capsule and the outer container enables tuning of thermal conduction to the NRAD coolant by altering its thickness and its gas-mixture. An inert gas mixture ratio in the gas-gap ensures the configurations reached a targeted average salt temperature of 600oC, while avoiding salt freezing or exceeding material limits. A resistive heater placed within a thermowell and controls the temperature of the experiment (both when the reactor is on or off). The selected configurations can contain over 10 cm3 of fuel-bearing chloride salt, which is sufficient for the purposes of the post-irradiation examination (PIE) and provides sufficient volume for two submerged thermocouple probes to monitor salt temperature. The capsule wall material is Inconel 625, and weld qualifications for the assembly have been developed. A glove-box laser weld technique was refined as part of this process to ensure a leak-tight assembly for the salt-bearing assembly and reduce the risks of impurities permeating into the salt. This work was supported through the INL Laboratory Directed Research & Development (LDRD) Program under DOE Idaho Operations Office Contract DE-AC07-05ID14517.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗
NASA NTRS1973

A study of the thermoregulatory characteristics of a liquid-cooled garment with automatic temperature control based on sweat rate: Experimental investigation and biothermal man-model development

Experimental results for three subjects walking on a treadmill at exercise rates of up to 590 watts showed that thermal comfort could be maintained in a liquid cooled garment by using an automatic temperature controller based on sweat rate. The addition of head- and neck-cooling to an Apollo type liquid cooled garment increased its effectiveness and resulted in greater subjective comfort. The biothermal model of man developed in the second portion of the study utilized heat rates and exchange coefficients based on the experimental data, and included the cooling provisions of a liquid-cooled garment with automatic temperature control based on sweat rate. Simulation results were good approximations of the experimental results.

Chambers, A. B.↗
DOE OSTI2018

Characterization of Micro-arc Oxidation Coatings on 6N01 Aluminum Alloy Under Different Electrolyte Temperature Control Modes

The micro-arc oxidation coatings of 6N01 aluminum alloy produced under different control modes of the electrolyte temperature are discussed in detail. Compared to those coated by a thermostatically controlled treatment, the coatings had different surface characterizations when they were coated without controlling the electrolyte temperature, particularly after treatment involving boiling electrolytes. Scanning electron microscopy and confocal laser scanning microscopy were used to observe the morphology of the coatings. Energy-dispersive spectrometry and x-ray diffractometer were used to characterize their elemental and crystalline phase compositions. The results indicate that the treatment without a controlled electrolyte temperature ultimately led to a thicker and rougher film with a respectably thick inner barrier film, a lower content of γ-Al{sub 2}O{sub 3} and better corrosion resistance.

36 MATERIALS SCIENCE↗
DOE OSTI2023

Design and Fabrication of a Temperature-Controlled Fueled Molten Salt Capsule Irradiation Experiment

Idaho National Laboratory (INL) is developing a Molten salt Research Temperature-controlled Irradiation (MRTI) experimental capsule for the Neutron Radiography (NRAD) reactor. The experiment is envisaged to be versatile and able to host a variety of salt-wall material combinations. The first test is designed to contain actinide-bearing chloride salt, which previously has not been subjected to a neutron field. The main objectives of the experiment are to produce irradiated salt samples for Post Irradiation Examination (PIE), to evaluate salt behavior under irradiation, and to test in-situ sensors/instrumentation. The final design for the experiment completed in 2022, and fabrication of the experiment is underway. The salt is double encapsulated providing insulation and redundancy in the case of leakage. A gas-gap between the inner capsule and the outer container enables tuning of thermal conduction to the NRAD coolant by altering its thickness and its gas-mixture. An inert gas mixture ratio in the gas-gap ensures the configurations reached a targeted average salt temperature of 600oC, while avoiding salt freezing or exceeding material limits. A resistive heater placed within a thermowell and controls the temperature of the experiment (both when the reactor is on or off). The selected configurations can contain over 10 cm3 of fuel-bearing chloride salt, which is sufficient for the purposes of the post-irradiation examination (PIE) and provides sufficient volume for two submerged thermocouple probes to monitor salt temperature. The capsule wall material is Inconel 625, and weld qualifications for the assembly have been developed. A glove-box laser weld technique was refined as part of this process to ensure a leak-tight assembly for the salt-bearing assembly and reduce the risks of impurities permeating into the salt. This work was supported through the INL Laboratory Directed Research & Development (LDRD) Program under DOE Idaho Operations Office Contract DE-AC07-05ID14517.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗
DOE OSTI2014

100 s extraction of negative ion beams by using actively temperature-controlled plasma grid

Long pulse beam extraction with a current density of 120 A/m{sup 2} for 100 s has been achieved with a newly developed plasma grid (PG) for the JT-60SA negative ion source which is designed to produce high power and long pulse beams with a negative ion current of 130 A/m{sup 2} (22 A) and a pulse length of 100 s. The PG temperature is regulated by fluorinated fluids in order to keep the high PG temperature for the cesium-seeded negative ion production. The time constant for temperature controllability of the PG was measured to be below 10 s, which was mainly determined by the heat transfer coefficient of the fluorinated fluid. The measured decay time of the negative ion current extracted from the actively temperature-controlled PG was 430 s which was sufficient for the JT-60SA requirement, and much longer than that by inertial-cooling PG of 60 s. Obtained results of the long pulse capability are utilized to design the full size PG for the JT-60SA negative ion source.

70 PLASMA PHYSICS AND FUSION TECHNOLOGY↗
NASA NTRS1982

A temperature control design for a tapered element oscillating microbalance sensing surface

A design study is presented which shows that a tapered element oscillating microbalance can be adapted for temperature control under space application by mating with multistage thermoelectric coolers in such a way that an integral structure evolves. The control of the temperature of the sensing surface can be achieved in a number of ways. An indirect method which uses a measurement of the absorbed power is recommended. The design goals can be met if a relaxation of the power requirement can be considered.

Source record↗
NASA NTRS2003

Microelectromechanical System (MEMS) Device Being Developed for Active Cooling and Temperature Control

High-capacity cooling options remain limited for many small-scale applications such as microelectronic components, miniature sensors, and microsystems. A microelectromechanical system (MEMS) using a Stirling thermodynamic cycle to provide cooling or heating directly to a thermally loaded surface is being developed at the NASA Glenn Research Center to meet this need. The device can be used strictly in the cooling mode or can be switched between cooling and heating modes in milliseconds for precise temperature control. Fabrication and assembly employ techniques routinely used in the semiconductor processing industry. Benefits of the MEMS cooler include scalability to fractions of a millimeter, modularity for increased capacity and staging to low temperatures, simple interfaces, limited failure modes, and minimal induced vibration. The MEMS cooler has potential applications across a broad range of industries such as the biomedical, computer, automotive, and aerospace industries. The basic capabilities it provides can be categorized into four key areas: 1) Extended environmental temperature range in harsh environments; 2) Lower operating temperatures for electronics and other components; 3) Precision spatial and temporal thermal control for temperature-sensitive devices; and 4) The enabling of microsystem devices that require active cooling and/or temperature control. The rapidly expanding capabilities of semiconductor processing in general, and microsystems packaging in particular, present a new opportunity to extend Stirling-cycle cooling to the MEMS domain. The comparatively high capacity and efficiency possible with a MEMS Stirling cooler provides a level of active cooling that is impossible at the microscale with current state-of-the-art techniques. The MEMS cooler technology builds on decades of research at Glenn on Stirling-cycle machines, and capitalizes on Glenn s emerging microsystems capabilities.

Beach, Duane E.↗
NASA NTRS1991

Controlled Temperature Gradient Improves Freezing Alloy

Controlled gradient of temperature in advancing zone of solidification increases fatigue life of directionally solidified nickel-base superalloy. Improved solidification process eliminates, reduces, or controls microstructure of deleterious brittle phases, including carbides and gamma/gamma prime eutectic. Also reduces microsegregation and makes discrete carbides (if present) become fine and blocky. Expected to improve properties of other alloys, of both directionally-solidified polycrystalline and single-crystal forms.

Schmidt, Deborah↗
NASA NTRS2004

Solid-state Distributed Temperature Control for International Space Station

A newly developed solid-state temperature controller will offer greater flexibility in the thermal control of aerospace vehicle structures. A status of the hardware development along with its implementation on the Multi- Purpose Logistics Module will be provided. Numerous advantages of the device will also be discussed with regards to current and future flight vehicle implementations.

Holladay, Jon B.↗
DOE OSTI2019

Non-contact temperature control system for microfluidic devices

The present invention relates to a temperature control system for a microfluidic device. The system allows for non-contact heating by employing an infrared emitter. In some instances, the system can be used in conjunction with a centrifugal microfluidic device. Optionally, a mask can be implemented to provide selective heating of desired assay areas of the device.

Phaneuf, Christopher↗
NASA NTRS1983

Temperature-controlled quartz crystal microbalance measurements on Space Transport System (STS-2)

The purpose of the Temperature-Controlled Quartz Crystal Microbalance (TQCM) system on STS-2 was to measure condensible molecular flux in the payload bay of the Space Shuttle as a function of temperature, direction, and time. Five quartz crystal microbalance sensors were located in the IECM to measure molecular adsorption in each of the Orbiter axes, +X (fore), -X (aft), +Y (starboard), -Y (port), and -Z (up, perpendicular to payload bay). The temperature of each sensor was controlled by a thermoelectric device so contamination could be measured as a function of four preset temperatures: +30, 0, -30, and -60 C. When orbital altitude was reached, the TQCM sensors began their orbital measuring cycle routine. The sensors were commanded to 80 C for 30 min, which was used as an initial clean-up. They were then stepped through a program of 2-nr collection periods at each temperature with a 30-min, 80 C period between each collection period. The collection periods progressed in descending order from +30 to -60 C and, then the cycle was repeated. Since the STS-2 orbital phase lasted approximately 53 hrs, the TQCM system completed four cycles and was in the fifth when the mission was terminated.

Fountain, J. A.↗
NASA NTRS2008

Fault-Tolerant, Multiple-Zone Temperature Control

A computer program has been written as an essential part of an electronic temperature control system for a spaceborne instrument that contains several zones. The system was developed because the temperature and the rate of change of temperature in each zone are required to be maintained to within limits that amount to degrees of precision thought to be unattainable by use of simple bimetallic thermostats. The software collects temperature readings from six platinum resistance thermometers, calculates temperature errors from the readings, and implements a proportional + integral + derivative (PID) control algorithm that adjusts heater power levels. The software accepts, via a serial port, commands to change its operational parameters. The software attempts to detect and mitigate a host of potential faults. It is robust to many kinds of faults in that it can maintain PID control in the presence of those faults.

Granger, James↗
NASA NTRS1978

Vapor-modulated heat pipe for improved temperature control

Dryout induced by vapor throttling makes control of equipment temperature less dependent on variations in sink environment. Mechanism controls flow of vapor in heat pipe by using valve in return path to build difference in pressure and also difference in saturation temperature of the vapor. In steady state, valve closes just enough to produce partial dryout that achieves required temperature drop.

Edwards, D. K.↗
DOE OSTI2017

System and method for temperature control in an oxygen transport membrane based reactor

A system and method for temperature control in an oxygen transport membrane based reactor is provided. The system and method involves introducing a specific quantity of cooling air or trim air in between stages in a multistage oxygen transport membrane based reactor or furnace to maintain generally consistent surface temperatures of the oxygen transport membrane elements and associated reactors. The associated reactors may include reforming reactors, boilers or process gas heaters.

03 NATURAL GAS↗