Search NASA⌕ Search

SEARCH · Search NASA

Results for “Electricity consumption”

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.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 55 records · Page 3
All sourcesNASA NTRSDOE OSTI
NASA NTRS2015

Off Grid Photovoltaic Wastewater Treatment and Management Lagoons

The SSC wastewater treatment system is comprised of key components that require a constant source of electrical power or diesel fuel to effectively treat the wastewater. In alignment with the President's new Executive Order 13653, Planning for Federal Sustainability in the Next Decade, this project aims to transform the wastewater treatment system into a zero emissions operation by incorporating the advantages of an off grid, photovoltaic system. Feasibility of implementation will be based on an analytical evaluation of electrical data, fuel consumption, and site observations.

LaPlace, Lucas A.↗
NASA NTRS2003

Effects Of Environmental And Operational Stresses On RF MEMS Switch Technologies For Space Applications

Micro Electro Mechanical Systems (MEMS) have been heralded for their ability to provide tremendous advantages in electronic systems through increased electrical performance, reduced power consumption, and higher levels of device integration with a reduction of board real estate. RF MEMS switch technology offers advantages such as low insertion loss (0.1- 0.5 dB), wide bandwidth (1 GHz-100 GHz), and compatibility with many different process technologies (quartz, high resistivity Si, GaAs) which can replace the use of traditional electronic switches, such as GaAs FETS and PIN Diodes, in microwave systems for low signal power (x < 500 mW) applications. Although the electrical characteristics of RF MEMS switches far surpass any existing technologies, the unknown reliability, due to the lack of information concerning failure modes and mechanisms inherent to MEMS devices, create an obstacle to insertion of MEMS technology into high reliability applications. All MEMS devices are sensitive to moisture and contaminants, issues easily resolved by hermetic or near-hermetic packaging. Two well-known failure modes of RF MEMS switches are charging in the dielectric layer of capacitive membrane switches and contact interface stiction of metal-metal switches. Determining the integrity of MEMS devices when subjected to the shock, vibration, temperature extremes, and radiation of the space environment is necessary to facilitate integration into space systems. This paper will explore the effects of different environmental stresses, operational life cycling, temperature, mechanical shock, and vibration on the first commercially available RF MEMS switches to identify relevant failure modes and mechanisms inherent to these device and packaging schemes for space applications. This paper will also describe RF MEMS Switch technology under development at NASA GSFC.

Jah, Muzar↗
NASA NTRS2000

Thermal Control and Enhancement of Heat Transport Capacity of Two-Phase Loops With Electrohydrodynamic Conduction Pumping

There are three kinds of electrohydrodynamics (EHD) pumping based on Coulomb force: induction pumping, ion-drag pumping, and pure conduction pumping. EHD induction pumping relies on the generation of induced charges. This charge induction in the presence of an electric field takes place due to a non-uniformity in the electrical conductivity of the fluid which can be caused by a non-uniform temperature distribution and/or an inhomogeneity of the fluid (e.g. a two-phase fluid). Therefore, induction pumping cannot be utilized in an isothermal homogeneous liquid. In order to generate Coulomb force, a space charge must be generated. There are two main mechanisms for generating a space charge in an isothermal liquid. The first one is associated with the ion injection at a metal/liquid interface and the related pumping is referred to as ion-drag pumping. Ion-drag pumping is not desirable because it can deteriorate the electrical properties of the working fluid. The second space charge generation mechanism is associated with the heterocharge layers of finite thickness in the vicinity of the electrodes. Heterocharge layers result from dissociation of the neutral electrolytic species and recombination of the generated ions. This type of pumping is referred to as pure conduction pumping. This project investigates the EHD pumping through pure conduction phenomenon. Very limited work has been conducted in this field and the majority of the published papers in this area have mistakenly assumed that the electrostriction force was responsible for the net flow generated in an isothermal liquid. The main motivation behind this study is to investigate an EHD conduction pump for a two-phase loop to be operated in the microgravity environment. The pump is installed in the liquid return passage (isothermal liquid) from the condenser section to the evaporator section. Unique high voltage and ground electrodes have been designed that generate sufficient pressure heads with very low electric power requirements making the EHD conduction pumping attractive to applications such as two-phase systems (e.g. capillary pumped loops and heat pipes). Currently, the EHD conduction pump performance is being tested on a two-phase loop under various operating conditions in the laboratory environment. The simple non-mechanical and lightweight design of the EHD pump combined with the rapid control of performance by varying the applied electric field, low power consumption, and reliability offer significant advantages over other pumping mechanisms; particularly in reduced gravity applications.

Seyed-Yagoobi, J.↗
NASA NTRS2000

Adapting PC104Plus for Space

This article addresses the issues associated with adapting the commercial PC104Plus standard and its associated architecture to the requirements of space applications. In general, space applications exhibit extreme constraints on power, weight, and volume. EMI and EMC are also issues of significant concern. Additionally, space applications have to survive high radiation environment. Finally, NASA is always concerned about achieving cost effective solutions that are compatible with safety and launch constraints. Weight and volume constraints are directly related to high launch cost. Power on the other hand is not only related to the high launch costs, but are related to the problem of dissipating the resulting heat once in space. The article addresses why PC104Plus is an appropriate solution for the weight and volume issues. The article also addresses what NASA did electrically to reduce power consumption and mechanically dissipate the associated heat in a microgravity and vacuum environment, and how these solutions allow NASA to integrate various sizes of ruggedized custom PC104 boards with COTS, PC104 complaint boards for space applications. In addition to the mechanical changes to deal with thermal dissipation NASA also made changes to minimize EMI. Finally, radiation issues are addressed as well as the architectural and testing solutions and the implications for use of COTS PC104Plus boards.

Abbott, Larry↗
NASA NTRS2011

Operational Phase Life Cycle Assessment of Select NASA Ground Test Facilities

NASA's Aeronautics Test Program (ATP) is responsible for many large, high-energy ground test facilities that accomplish the nation s most advanced aerospace research. In order to accomplish these national objectives, significant energy and resources are consumed. A select group of facilities was analyzed using life-cycle assessment (LCA) to determine carbon footprint and environmental impacts. Most of these impacts stem from electricity and natural gas consumption, used directly at the facility and to generate support processes such as compressed air and steam. Other activities were analyzed but determined to be smaller in scale and frequency with relatively negligible environmental impacts. More specialized facilities use R-134a, R-14, jet fuels, or nitrogen gas, and these unique inputs can have a considerable effect on a facility s overall environmental impact. The results of this LCA will be useful to ATP and NASA as the nation looks to identify its top energy consumers and NASA looks to maximize research output and minimize environmental impact. Keywords: NASA, Aeronautics, Wind tunnel, Keyword 4, Keyword 5

Sydnor, George H.↗
NASA NTRS2016

Cooling of Electric Motors Used for Propulsion on SCEPTOR

Benefits of Electric Power: Reduced energy consumption, Lower emissions, Less noise. Traction motors: Permanent magnet, Synchronous, High torque at low rotational speeds, High power density, (High concentration of heat). Annular inlet: Very compatible with PM motors, (Provides cooling where needed, No need for complicated ducting, Leads to a larger motor diameter which is beneficial for motor torque) Effect of prop wash on heat transfer coefficients: Assumed propeller induced turbulence would increase heat transfer coefficients, Holmes, Obara Yip reported 'propeller slipstream showed little if any apparent effect of the slip stream', Derlaga @ LaRC also found little change in heat transfer in the wake of the propeller.

Aircraft↗
NASA NTRS2019

Propeller-Wing Integration on the Parallel Electric-Gas Architecture with Synergistic Utilization Scheme (PEGASUS) Aircraft

Electrically powered aircraft show promise for reducing emissions and energy consumption, but many of the opportunities surrounding electric propulsion have yet to be explored. One opportunity is the use of multiple propulsors or distributed propulsion for improved propulsion airframe integration. However, the size, power, location, and optimum number of propulsors has not been thoroughly vetted. This paper describes the use of FlightStream, a surface vorticity solver, to investigate the aerodynamic-propulsion integration of four propulsors across the leading edge of a wing, two inboard and two at the wingtips, as proposed in the NASA Parallel Electric-Gas Architecture with Synergistic Utilization Scheme (PEGASUS) concept. FlightStream was used to determine the minimum power required for cruise for the PEGASUS aircraft. The study found that tip propellers are effective at lowering both viscous and induced drag when compared to inboard propellers alone or inboard propellers combined with tip propellers. Despite this drag savings, the propulsive efficiency was reduced when a single propeller class was used, resulting in a higher system power consumption when compared with using multiple propeller classes. Reductions in propeller efficiency are related to increases in disc and blade loading of the propeller; thus, larger propellers or higher tip speeds are seen as possible means of to improve system performance.

Blaesser, Nathaniel J.↗
NASA NTRSDate not supplied

Power Optimal Control Allocation for Distributed Electric Propulsion in a Series/Parallel Hybrid Powertrain

This paper describes a thrust allocation scheme that minimizes power consumption in an electrified powertrain with Distributed Electric Propulsion. It takes advantage of an observation about component efficiency maps, that efficiency is often highest at high torque/high speed conditions. This optimal approach is demonstrated to satisfy total thrust and net yaw axis torque requirements, making it suitable for utilizing differential thrust for maneuvering.

electrified aircraft propulsion↗
NASA NTRSDate not supplied

Power Optimal Control Allocation for Distributed Electric Propulsion in a Series/Parallel Hybrid Powertrain

This paper describes a thrust allocation scheme that minimizes power consumption in an electrified powertrain with Distributed Electric Propulsion. It takes advantage of an observation about component efficiency maps, that efficiency is often highest at high torque/high speed conditions. This optimal approach is demonstrated to satisfy total thrust and net yaw axis torque requirements, making it suitable for utilizing differential thrust for maneuvering.

electrified aircraft propulsion↗
NASA NTRS2026

Power Optimal Control Allocation for Distributed Electric Propulsion in a Series/Parallel Hybrid Powertrain

This paper describes a thrust allocation scheme that minimizes power consumption in an electrified powertrain with Distributed Electric Propulsion. It takes advantage of an observation about component efficiency maps, that efficiency is often highest at high torque/high speed conditions. This optimal approach is demonstrated to satisfy total thrust and net yaw axis torque requirements, making it suitable for utilizing differential thrust for maneuvering.

electrified aircraft propulsion↗
NASA NTRS1978

Test and evaluation of 23 electric vehicles for state-of-the-art assessment

Data developed by ERDA used to evaluate the performance parameters of modern electric vehicles is presented with reference to range, acceleration, coast-down, and braking. Eight of the tested vehicles had some type of regenerative braking system, which provided range increases from 1 to 31 percent. In comparison with conventional vehicles, performance was found to be lower, and reliability poorer. Energy consumption was the same, but electric power is less damaging to the environment than hydrocarbon fuels, and does not use up an increasingly scarce resource.

Dustin, M. O.↗
NASA NTRS1978

Possible environmental effects of increased coal use in California

If coal is to be utilized in California it must be made compatible with the state's drive toward restoring environmental quality. The impacts resulting from coal's mining and transportation, or from water consumption, water quality degradation and electric transmission line routing can probably be adequately mitigated through strong and early planning efforts, the use of improved control and process technologies, and sincere utility commitment. The socioeconomic impacts may prove somewhat more difficult to satisfactorily mitigate. Of greatest concern is adequate control of generated air pollutants and disposal of solid and liquid wastes since acceptable technologies or handling techniques have yet to be conclusively demonstrated.

Carey, D. L.↗
NASA NTRSDate not supplied

Subscale Hardware-In-The-Loop Results for Hybrid Electric Turbofan Controls Use Cases

NASA is investigating hybrid electric turbine engine systems for commercial transport aircraft due to the potentially significant improvements hybrid electric technology offers in performance, fuel consumption, and operational and design flexibility. Recently, the technology has been tested at full scale in partnership with industry and advanced to Technology Readiness Level 4. This presentation will focus on a recent subscale hardware-in-the-loop test of an open source turbofan engine model developed by NASA. The Advanced Geared Turbofan 30,000 lbf – electrified (AGTF30-e) engine is used as a reference model to demonstrate control system design and use cases for an example mild hybrid electric system with no large-scale energy storage. This model is run in real-time in NASA’s Hybrid Propulsion Emulation Rig (HyPER) and is used to drive an emulation of the turbomachinery system using subscale electric machines. This dynamic scaled shaft emulation interacts with a subscale (<100 kW) hybrid system consisting of electric machines, motor controllers, and a programmable electronic load. Specific use cases demonstrated include the use of Turbine Electrified Energy Management to improve operation during transients, megawatt-scale power extraction from the AGTF30-e, and power transfer between engine spools. Results related to the effectiveness of hybrid systems are qualitatively compared to results from industry testing.

Hybrid↗
NASA NTRS1982

Performance and operational economics estimates for a coal gasification combined-cycle cogeneration powerplant

A performance and operational economics analysis is presented for an integrated-gasifier, combined-cycle (IGCC) system to meet the steam and baseload electrical requirements. The effect of time variations in steam and electrial requirements is included. The amount and timing of electricity purchases from sales to the electric utility are determined. The resulting expenses for purchased electricity and revenues from electricity sales are estimated by using an assumed utility rate structure model. Cogeneration results for a range of potential IGCC cogeneration system sizes are compared with the fuel consumption and costs of natural gas and electricity to meet requirements without cogeneration. The results indicate that an IGCC cogeneration system could save about 10 percent of the total fuel energy presently required to supply steam and electrical requirements without cogeneration. Also for the assumed future fuel and electricity prices, an annual operating cost savings of 21 percent to 26 percent could be achieved with such a cogeneration system. An analysis of the effects of electricity price, fuel price, and system availability indicates that the IGCC cogeneration system has a good potential for economical operation over a wide range in these assumptions.

Nainiger, J. J.↗
NASA NTRSDate not supplied

Hybrid Electric Aircraft with Unlike Engine Degradation

Control solutions are applied to uneven engine performance degradation on a conceptual twin-engine transport-class aircraft. Such degradation can lead to asymmetric thrust, which requires rudder trim to maintain desired aircraft heading. This will increase drag and fuel consumption. With the introduction of hybrid-electric aircraft powertrains, new solutions to unwanted asymmetric thrust can be derived. Four control strategies are demonstrated on the power and propulsion system of such an aircraft. Compared with existing strategies, the methodology proposed in this paper controls electromechanical actuators coupled to engine shafts and balances the thrust produced by both engines potentially leading to a decrease in fuel burn. The engine represented in this study is NASA’s conceptual dual-shaft Advanced Geared Turbofan 30,000 lbf thrust class engine. The conceptual engine is hybridized with electric machines attached to both shafts. Simulation results are presented with various levels of degradation. The control strategies are compared based on fuel burn, thrust symmetry, and estimated system weight.

control↗
NASA NTRSDate not supplied

Hybrid Electric Aircraft with Unlike Engine Degradation

Control solutions are applied to uneven engine performance degradation on a conceptual twin-engine transport-class aircraft. Such degradation can lead to asymmetric thrust, which requires rudder trim to maintain desired aircraft heading. This will increase drag and fuel consumption. With the introduction of hybrid-electric aircraft powertrains, new solutions to unwanted asymmetric thrust can be derived. Four control strategies are demonstrated on the power and propulsion system of such an aircraft. Compared with existing strategies, the methodology proposed in this paper controls electromechanical actuators coupled to engine shafts and balances the thrust produced by both engines potentially leading to a decrease in fuel burn. The engine represented in this study is NASA’s conceptual dual-shaft Advanced Geared Turbofan 30,000 lbf thrust class engine. The conceptual engine is hybridized with electric machines attached to both shafts. Simulation results are presented with various levels of degradation. The control strategies are compared based on fuel burn, thrust symmetry, and estimated system weight.

control↗
NASA NTRS1976

Auxiliary Payload Power System thermal control

The Auxiliary Payload Power System (APPS) provides supplementary power and cooling to Space Processing Application (SPA) experiments to be mounted in the APPS and the Spacelab in the Shuttle Payload Bay. SPA experiment operations are planned for early Shuttle flights. This paper presents thermal control study results for preliminary analysis and design definition of the APPS. A 100/sq m, three-wing, pumped-fluid, deployable radiator with separate APPS equipment and SPA experiments coolant loops was selected as the baseline. The system is capable of rejecting the heat (approximately 26 kw) associated with the production and consumption of approximately 16 kw of electrical power produced by the APPS fuel cells for a worst case radiator orientation. For the most favorable orientation, the heat rejection and power capability approach 38 and 24 kw, respectively. Alternate approaches were evaluated, such as heat pipes for the radiator and alternate fluids for the coolant loops. Emphasis was placed on using Shuttle developed hardware: coolant pumps, heat exchangers, fluids, and radiator technology.

Nagel, R. G.↗