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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 775 records · Page 43
All sourcesNASA NTRSDOE OSTI
DOE OSTI2020

Quantum nondemolition photon counting with a hybrid electromechanical probe

Quantum nondemolition (QND) measurements of photons is a much pursued endeavor in the field of quantum optics and quantum information processing. Here, we propose a hybrid optoelectromechanical platform that integrates a cavity system with a hybrid electromechanical probe for QND photon counting. Building upon a mechanical-mode-mediated nonperturbative electro-optical dispersive coupling, our protocol performs the QND photon counting measurement by means of the current-voltage characteristics of the probe. In particular, we show that the peak voltage shift of the differential conductance is linearly dependent on the photon occupation number, thus providing a sensitive measure of the photon number, especially in the strong optomechanical coupling regime. Here, given that our proposed hybrid system is compatible with state-of-the-art experimental techniques, we discuss its implementations and anticipate applications in quantum optics and polariton physics.

71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗
NASA NTRS1976

Design and evaluation of a 3 million DN series-hybrid thrust bearing

The bearing, consisting of a 150-mm ball bearing and a centrifugally actuated, conical, fluid-film bearing, was fatigue tested. Test conditions were representative of a mainshaft ball bearing in a gas turbine engine operating at maximum thrust load to simulate aircraft takeoff conditions. Tests were conducted up to 16000 rpm and at this speed an axial load of 15568 newtons (3500 lb) was safely supported by the hybrid bearing system. Through the series-hybrid bearing principle, the effective ball bearing speed was reduced to approximately one-half of the shaft speed. It was concluded that a speed reduction of this magnitude results in a ten-fold increase in the ball bearing fatigue life. A successful evaluation of fluid-film bearing lubricant supply failure was performed repeatedly at an operating speed of 10,000 rpm. A complete and smooth changeover to full-scale ball bearing operation was effected when the oil supply to the fluid-film bearing was cut off. Reactivation of the fluid-film oil supply system resulted in a flawless return to the original mode of hybrid operation.

Scibbe, H. W.↗
NASA NTRS1995

On the application of Chimera/unstructured hybrid grids for conjugate heat transfer

A hybrid grid system that combines the Chimera overset grid scheme and an unstructured grid method is developed to study fluid flow and heat transfer problems. With the proposed method, the solid structural region, in which only the heat conduction is considered, can be easily represented using an unstructured grid method. As for the fluid flow region external to the solid material, the Chimera overset grid scheme has been shown to be very flexible and efficient in resolving complex configurations. The numerical analyses require the flow field solution and material thermal response to be obtained simultaneously. A continuous transfer of temperature and heat flux is specified at the interface, which connects the solid structure and the fluid flow as an integral system. Numerical results are compared with analytical and experimental data for a flat plate and a C3X cooled turbine cascade. A simplified drum-disk system is also simulated to show the effectiveness of this hybrid grid system.

Kao, Kai-Hsiung↗
NASA NTRS1993

Hybrid rocket propulsion

Topics addressed are: (1) comparison of the theoretical impulses; (2) comparison of the density-specific impulses; (3) general propulsion system features comparison; (4) hybrid systems, booster applications; and (5) hybrid systems, upper stage propulsion applications.

Holzman, Allen L.↗
NASA NTRS2013

Modeling and Analysis of Asynchronous Systems Using SAL and Hybrid SAL

We present formal models and results of formal analysis of two different asynchronous systems. We first examine a mid-value select module that merges the signals coming from three different sensors that are each asynchronously sampling the same input signal. We then consider the phase locking protocol proposed by Daly, Hopkins, and McKenna. This protocol is designed to keep a set of non-faulty (asynchronous) clocks phase locked even in the presence of Byzantine-faulty clocks on the network. All models and verifications have been developed using the SAL model checking tools and the Hybrid SAL abstractor.

Tiwari, Ashish↗
DOE OSTI2024

Photovoltaic Analysis and Response Support (PARS) Platform for Solar Situational Awareness and Resiliency Services

The project's primary objective is to develop a digital-twin based Photovoltaic (PV) Analysis and Response Support (PARS) platform, which aims to provide real-time situational awareness and optimal response plans. This platform is designed to enhance the performance of hybrid PV systems, making them competitive with or even superior to conventional generation resources. The PARS platform enabled the project team to develop and evaluate an extensive suite of grid support functionalities for the hybrid PV systems to enhance grid performance, across key areas including visibility, dispatchability, security, resilience, and reliability. Given the global push toward achieving 100% clean energy by 2035, there is a significant increase in the integration of inverter-based resources (IBRs) throughout the energy grid. Effectively managing the inherent variability and uncertainty associated with IBRs is crucial for ensuring cost-effectiveness, reliability, and security in both the main grid and islanded microgrids. Constrained to a limited array of IEEE test systems or standard feeder models, traditional IBR modeling struggles to assimilate new field data, accurately reflect system dynamics, and adapt to the evolving energy landscape. In our project, we embraced a Digital Twin (DT) strategy for crafting the PARS platform. A digital twin acts as a precise virtual counterpart of a physical system, built on historical data and continuously honed with real-time insights. This enables the high-fidelity DT to accurately mirror current system operations and forecast future scenarios. Consequently, the PARS platform becomes an ideal environment for testing and refining monitoring, control, power, and energy management algorithms designed to boost hybrid PV system performance. The defining feature of the PARS platform, distinguishing it from other advanced simulation tools, is its exceptional adaptability. This is achieved by employing actual network topologies and utilizing real-time field data for fine-tuning and calibration, ensuring a close emulation of real-world conditions. The project deliverables include: 1) High-fidelity IBR models and tools for real-time parameterization, utilizing real-time field measurements to refine IBR models for enhanced accuracy and performance; 2) Grid-forming and Grid-following capabilities to deliver resilience services, including blackstart, voltage and frequency support, cold-load pick-up, power reserves, and three-phase load balancing across grid-connected and microgrid settings; 3) Machine learning-based forecasting tools and methods for generating synthetic data and topologies, creating diverse and realistic simulation environments for evaluating varied operational scenarios; 4) Advanced microgrid power and energy management algorithms for optimizing the integration and operation of PV, storage, and demand response resources within both feeder and community scales. The power grid data sets are provided by four utility companies in North Carolina and the New York Power Administration. Acting as industry advisors, our industry partners communicated stakeholder needs and regulatory standards to the research teams, aiding technology transfer by incorporating the developed methodologies into their daily operations. This collaboration ensures that the PARS platform, functioning as a power system digital twin, enhances our understanding of IBR dynamic behaviors and enables the development and evaluation of IBR control functions that match or exceed the capabilities of conventional synchronous generators.

14 SOLAR ENERGY↗
NASA NTRS2019

A Single Stage to Orbit Design for a Hybrid Mars Ascent

A Single Stage to Orbit (SSTO) hybrid propulsion system has been previously studied as an option for a conceptual Mars Ascent Vehicle (MAV). The hybrid motor uses a wax-based fuel developed specifically for this application, so it can take advantage of a single port design. The oxidizer is Mixed Oxides of Nitrogen (MON-25). Higher Nitric Oxide concentrations have been discussed in the past, however, the lower temperature capability is no longer needed. The MAV Payload Assembly (MPA), which would house the Orbiting Sample (OS) has changed substantially from previous iterations and has become more compact. Benefits of the hybrid option include its predicted low temperature behavior, high performance and ability to restart (enabling the SSTO). However, the hybrid technology remained at a relatively low Technology Readiness Level (TRL). In an attempt to increase the TRL, a technology development program has been underway for the past four years. The results of the technology development program are now being incorporated to an updated concept for a hybrid Mars Ascent Vehicle, with the eventual goal of informing a hybrid propulsion design that closes under the guidelines currently envisioned for a potential Mars Sample Return campaign. This paper focuses on the hybrid propulsion system design and the preliminary results from the first part of the FY19 technology development program (October 2018 to July 2019) and includes some results from a Preliminary Architecture Assessment (PAA) study. In the PAA, experts from all relevant subsystems (propulsion, avionics, GN&C, structures, thermal, etc.) are brought together to determine an updated vehicle design. The PAA is being run out of Marshall Space Flight Center (MSFC) in coordination with the Mars Sample Return study lead by the Jet Propulsion Laboratory (JPL). Currently, it is thought that the Mars Ascent Vehicle would be housed in a Sample Retrieval Lander (SRL), along with a fetch rover. The SRL would be responsible for several crucial functions on the MAV including heating, erection and providing the ignition signal. This paper will also outline the future testing and path forward through the rest of the fiscal year. This includes full scale testing at Whittinghill Aerospace, hypergolic additive testing at Purdue, evaluation of adding hypergolic additives to a full-scale grain. A hybrid fuel formulation has been updated with a reduced regression rate, which again was developed by Space Propulsion Group. This design will be used to determine the benefits of a hybrid versus solid propulsion system for a MAV, as they fit into the larger vision for a potential Mars Sample Return campaign.

Story, George↗
NASA NTRSDate not supplied

Hybrid Model Based Approaches for Systems Health Management and Prognostics

To facilitate and solve the prediction problem, awareness of the current health state of the system is key, since it is necessary to perform condition-based predictions. To accurately predict the future state of any system, it is required to possess knowledge of its current health state and future operational conditions. Latest achievements of data-driven algorithms in regression of complex nonlinear functions and classification tasks have generated a growing interest in artificial intelligence for industrial applications. Complex multi-physics models as well as digital twins, once purely built on physics and corresponding simplified lumped parameter iterations, can now benefit from machine learning algorithms to mitigate the lack of understanding of some complex behavior. Given models of the current and future system behavior, a general approach of model-based prognostics can solve the prediction problem and further decision making. In principle, data driven approaches can replace expensive experimental test-setups as well as reduce the number of simulations needed to explore, e.g., the parametric space of a multi-parameter model. Nonetheless, the limitations of pure data-driven methods came to light rather quickly, at least for some industries. In many industrial applications, data acquisition is costly, and the volume of data that can be collected does not satisfy the requirements for an effective model training and cross-validation. Therefore, some recent works in the area of machine learning is focusing on blending physics with data-driven algorithms, thus mitigating the drawbacks of the two approaches and emphasizing respective advantages. Partial physical knowledge of the problem can aid the learning process by “guiding” the algorithm towards efficient solutions that satisfy the physics driving the system behavior. The result is a hybrid modeling approach combining physical knowledge as well data driven methods to develop a unified hybrid approach. A hybrid framework for fusing information from physics-based performance models along with deep learning algorithms for prognostics of complex safety critical systems is presented. In this framework, physics-based performance models infer unobservable model parameters related to the system's components health solving a calibration problem in the deep learning approach.

Hybrid Modeling↗
DOE OSTI2022

Variable Resource Resilience: How Systems Experience Increased Resilience from Variable and Hybrid Resources

Variable resources like wind and solar are often seen as detriments to system resilience rather than benefits because they may not be available with the capacities or services required during a high-impact low-frequency (HILF) event, whether that is a physical threat, natural disaster, or cyber attack. However, resilience goals and metrics are inadequate for electric energy delivery systems with inverter-based resources. Examination of this topic reveals that renewable resources are well suited to combat many resilience hazards due to local resource availability. Metrics that demonstrate the resilience value of variable resources are presented and categorized for resource (wind, solar, storage, hybrid) and installation type (bulk utility scale, behind-the-meter, front-of-the-meter, isolated). Distributed and hybrid systems can further enhance resilience benefits my maximizing resource potential for a locality. A case study demonstrating quantitative resilience benefits from wind alone is provided for St. Mary's, AK, which concludes that hundreds of thousands of dollars are saved by the addition of a wind turbine in the face of realistic fuel shortage and extreme winter weather scenarios.

17 WIND ENERGY↗
DOE OSTI2024

Combinatorial split-ring and spiral metaresonator for efficient magnon-photon coupling

Developing hybrid materials and structures for electromagnetic wave engineering has been a promising route towards novel functionalities and tunabilities in many modern applications. Despite its established success in engineering optical light and terahertz waves, the implementation of metaresonators operating in the microwave band is still emerging, especially the implementation of metaresonators that allow on-chip integration and size miniaturization, which is crucial for developing hybrid quantum systems in the microwave band. In this work, we present a microwave metaresonator consisting of split-ring and spiral resonators, and implement it for the investigation of photon-magnon coupling for hybrid magnonic applications. We observe broadened bandwidth of the split-ring modes augmented by the additional spiral resonator, and, by coupling the modes to a magnetic sample, the resultant photon-magnon coupling can be significantly enhanced by more than tenfold. Furthermore, our work suggests that combinatorial, hybrid microwave resonators may be a promising approach towards future development and implementation of photon-magnon coupling in hybrid magnonic systems.

71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗
NASA NTRSDate not supplied

Mars Ascent Vehicle Hybrid PropulsionEffort

A technology development program was undertaken to determine if the benefits of hybrid rocket propulsion could be realized for a Mars Ascent Vehicle (MAV) application. Specifically, the goal of this program was to increase the Technology Readiness Level (TRL) of a hybrid propulsion system such that it could be considered for a potential Mars Sample Return Campaign. Over the course of approximately five years, a new, wax-based fuel was developed, characterized and tested with Mixed Oxides of Nitrogen (from MON-3 to MON-25). Various ignition mechanisms were tested and solid hypergolic additives were evaluated for their potential to ignite the hybrid motor. Several hot-fire test campaigns were completed at both sub- and full-scale. The technology development program was born out of a JPL study documented by Shotwell and Karp that identified the Single Stage to Orbit (SSTO) hybrid propulsion system for a potential Mars Ascent Vehicle to be the lowest Gross Lift Off Mass option from the ten configurations evaluated. Benefits of the hybrid option included its predicted favorable low temperature storage and operation behavior, high performance and ability to restart (enabling the SSTO). The main disadvantage of the hybrid option was its low TRL,as it essentially started as a blank sheet design with a new fuel development. Near the end of the technology development program, a Preliminary Architecture Assessment (PAA) was completed to evaluate a single-stage hybrid propulsion system and a two-stage solid propulsion system for a potential MAV. The solid propulsion system was selected for further study in 2019, primarily because of its flight heritage. While the hybrid technology development program made many strides, there was still a list of challenges to overcome. This paper will discuss the substantial progress and remaining challenges from the technology development effort from 2015 through 2019. This includes fuel development and reformulation, sub- and full-scale testing at Space Propulsion Group, full scale testing at Parabilis, full scale testing at Whittinghill Aerospace, hypergolic additive testing at Purdue and Penn State and the evaluation of adding hypergolic additives to a full-scale grain. It also includes a discussion of the design that resulted from the Preliminary Architecture Assessment.

hybrid rocket↗
NASA NTRSDate not supplied

Mars Ascent Vehicle Hybrid Propulsion Effort

A technology development program was undertaken to determine if the benefits of hybrid rocket propulsion could be realized for a Mars Ascent Vehicle (MAV) application. Specifically, the goal of this program was to increase the Technology Readiness Level (TRL) of a hybrid propulsion system such that it could be considered for a potential Mars Sample Return Campaign. Over the course of approximately five years, a new, wax-based fuel was developed, characterized and tested with Mixed Oxides of Nitrogen (from MON-3 to MON-25). Various ignition mechanisms were tested and solid hypergolic additives were evaluated for their potential to ignite the hybrid motor. Several hot-fire test campaigns were completed at both sub- and full-scale. The technology development program was born out of a JPL study documented by Shotwell and Karp that identified the Single Stage to Orbit (SSTO) hybrid propulsion system for a potential Mars Ascent Vehicle to be the lowest Gross Lift Off Mass option from the ten configurations evaluated. Benefits of the hybrid option included its predicted favorable low temperature storage and operation behavior, high performance and ability to restart (enabling the SSTO). The main disadvantage of the hybrid option was its low TRL, as it essentially started as a blank sheet design with a new fuel development. Near the end of the technology development program, a Preliminary Architecture Assessment (PAA) was completed to evaluate a single-stage hybrid propulsion system and a two-stage solid propulsion system for a potential MAV. The solid propulsion system was selected for further study in 2019, primarily because of its flight heritage. While the hybrid technology development program made many strides, there was still a list of challenges to overcome. This paper will discuss the substantial progress and remaining challenges from the technology development effort from 2015 through 2019. This includes fuel development and reformulation, sub- and full-scale testing at Space Propulsion Group, full scale testing at Parabilis, full scale testing at Whittinghill Aerospace, hypergolic additive testing at Purdue and Penn State and the evaluation of adding hypergolic additives to a fullscale grain. It also includes a discussion of the design that resulted from the Preliminary Architecture Assessment.

hybrid rocket↗
NASA NTRS1977

Full-color hybrid display

System presents realistic and properly proportioned image of runway with its associated lights as it appears at dusk or at night. Display employs high resolution cathode ray tube and color wheel to produce colored lights from computer generated signals. Lights are then superimposed on conventional television display of runway.

Chase, W. D.↗
NASA NTRS1977

A block iterative LU solver for weakly coupled linear systems

A hybrid technique, called the block iterative LU solver, is proposed for solving the linear equations resulting from a finite element numerical analysis of certain fluid dynamics problems where the equations are weakly coupled between distinct sets of variables. Either the block Jacobi iterative method or the block Gauss-Seidel iterative solver is combined with LU decomposition.

Cooke, C. H.↗
NASA NTRS1977

Digital simulation of a 30-cm diameter ion thruster control system

A hybrid model of a 30-cm diameter ion thruster and transistorized power processor was formulated and implemented on a digital computer. The control loops as presented are stable for normal values of loop gain when propellant line delay times are zero. Small oscillations are present in the loops when representative thruster delay times are included in the model. Discharge supply characteristics can affect the control loop oscillations. Recovery from runaway can be aggravated by delay time and, to a greater extent, by discharge supply characteristics.

Kudo, I.↗
NASA NTRS1982

Modular design attitude control system

A hybrid multilevel linear quadratic regulator (ML-LQR) approach was developed and applied to the attitude control of models of the rotational dynamics of a prototype flexible spacecraft and of a typical space platform. Three axis rigid body flexible suspension models were developed for both the spacecraft and the space platform utilizing augmented body methods. Models of the spacecraft with hybrid ML-LQR attitude control and with LQR attitude control were simulated and their response with the two different types of control were compared.

Chichester, F. D.↗