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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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All sourcesNASA NTRSDOE OSTI
NASA NTRS2010

History and Benefits of Engine Level Testing Throughout the Space Shuttle Main Engine Program

Rocket engine testing is important throughout a program s life and is essential to the overall success of the program. Space Shuttle Main Engine (SSME) testing can be divided into three phases: development, certification, and operational. Development tests are conducted on the basic design and are used to develop safe start and shutdown transients and to demonstrate mainstage operation. This phase helps form the foundation of the program, demands navigation of a very steep learning curve, and yields results that shape the final engine design. Certification testing involves multiple engine samples and more aggressive test profiles that explore the boundaries of the engine to vehicle interface requirements. The hardware being tested may have evolved slightly from that in the development phase. Operational testing is conducted with mature hardware and includes acceptance testing of flight assets, resolving anomalies that occur in flight, continuing to expand the performance envelope, and implementing design upgrades. This paper will examine these phases of testing and their importance to the SSME program. Examples of tests conducted in each phase will also be presented.

VanHooser, Katherine↗
NASA NTRS2004

Baseline Testing of Ultracapacitors for the Next Generation Launch Technology (NGLT) Project

The NASA John H. Glenn Research Center initiated baseline testing of ultracapacitors for the Next Generation Launch Transportation (NGLT) project to obtain empirical data for determining the feasibility of using ultracapacitors for the project. There are large transient loads associated with NGLT that require either a very large primary energy source or an energy storage system. The primary power source used for these tests is a proton exchange membrane (PEM) fuel cell. The energy storage system can consist of devices such as batteries, flywheels, or ultracapacitors. Ultracapacitors were used for these tests. Ultracapacitors are ideal for applications such as NGLT where long life, maintenance-free operation, and excellent low-temperature performance is essential. State-of-the-art symmetric ultracapacitors were used for these tests. The ultracapacitors were interconnected in an innovative configuration to minimize interconnection impedance. PEM fuel cells provide excellent energy density, but not good power density. Ultracapacitors provide excellent power density, but not good energy density. The combination of PEM fuel cells and ultracapacitors provides a power source with excellent energy density and power density. The life of PEM fuel cells is shortened significantly by large transient loads. Ultracapacitors used in conjunction with PEM fuel cells reduce the transient loads applied to the fuel cell, and thus appreciably improves its life. PEM fuel cells were tested with and without ultracapacitors, to determine the benefits of ultracapacitors. The report concludes that the implementation of symmetric ultracapacitors in the NGLT power system can provide significant improvements in power system performance and reliability.

Eichenberg, Dennis J.↗
NASA NTRS2005

Baseline Testing of Ultracapacitors for the Next Generation Launch Technology (NGLT) Project

The NASA John H. Glenn Research Center initiated baseline testing of ultracapacitors for the Next Generation Launch Transportation (NGLT) project to obtain empirical data for determining the feasibility of using ultracapacitors for the project. There are large transient loads associated with NGLT that require either a very large primary energy source or an energy storage system. The primary power source used for these tests is a proton exchange membrane (PEM) fuel cell. The energy storage system can consist of devices such as batteries, flywheels, or ultracapacitors. Ultracapacitors were used for these tests. Ultracapacitors are ideal for applications such as NGLT where long life, maintenance-free operation, and excellent low-temperature performance is essential. State-of-the-art symmetric ultracapacitors were used for these tests. The ultracapacitors were interconnected in an innovative configuration to minimize interconnection impedance. PEM fuel cells provide excellent energy density, but not good power density. Ultracapacitors provide excellent power density, but not good energy density. The combination of PEM fuel cells and ultracapacitors provides a power source with excellent energy density and power density. The life of PEM fuel cells is shortened significantly by large transient loads. Ultracapacitors used in conjunction with PEM fuel cells reduce the transient loads applied to the fuel cell, and thus appreciably improves its life. PEM fuel cells were tested with and without ultracapacitors, to determine the benefits of ultracapacitors. The report concludes that the implementation of symmetric ultracapacitors in the NGLT power system can provide significant improvements in power system performance and reliability.

Eichenberg, Dennis J.↗
NASA NTRS2011

Waterhammer Transient Simulation and Model Anchoring for the Robotic Lunar Lander Propulsion System

Waterhammer transients have the potential to adversely impact propulsion system design if not properly addressed. Waterhammer can potentially lead to system plumbing, and component damage. Multi-thruster propulsion systems also develop constructive/destructive wave interference which becomes difficult to predict without detailed models. Therefore, it is important to sufficiently characterize propulsion system waterhammer in order to develop a robust design with minimal impact to other systems. A risk reduction activity was performed at Marshall Space Flight Center to develop a tool for estimating waterhammer through the use of anchored simulation for the Robotic Lunar Lander (RLL) propulsion system design. Testing was performed to simulate waterhammer surges due to rapid valve closure and consisted of twenty-two series of waterhammer tests, resulting in more than 300 valve actuations. These tests were performed using different valve actuation schemes and three system pressures. Data from the valve characterization tests were used to anchor the models that employed MSCSoftware.EASY5 v.2010 to model transient fluid phenomena by using transient forms of mass and energy conservation. The anchoring process was performed by comparing initial model results to experimental data and then iterating the model input to match the simulation results with the experimental data. The models provide good correlation with experimental results, supporting the use of EASY5 as a tool to model fluid transients and provide a baseline for future RLL system modeling. This paper addresses tasks performed during the waterhammer risk reduction activity for the RLL propulsion system. The problem of waterhammer simulation anchoring as applied to the RLL system is discussed with results from the corresponding experimental valve tests. Important factors for waterhammer mitigation are discussed along with potential design impacts to the RLL propulsion system.

Stein, William B.↗
NASA NTRS2003

Combustion Of Metals In Reduced Gravity And Extraterrestrial Environments

The recent focus of this research project has been to model the combustion of isolated metal droplets and, in particular, to couple the existing theories and formulations of phenomena such as condensation, reaction kinetics, radiation, and surface reactions to formulate a more complete combustion model. A fully transient, one-dimensional (spherical symmetry) numerical model that uses detailed chemical kinetics, multi-component molecular transport mechanisms, condensation kinetics, and gas phase radiation heat transfer was developed. A coagulation model was used to simulate the particulate formation of MgO. The model was used to simulate the combustion of an Mg droplet in pure O2 and CO2. Methanol droplet combustion is considered as a test case for the solution method for both quasi-steady and fully transient simulations. Although some important processes unique to methanol combustion, such as water absorption at the surface, are not included in the model, the results are in sufficient agreement with the published data. Since the major part of the heat released in combustion of Mg, and in combustion of metals in general, is due to the condensation of the metal oxide, it is very important to capture the condensation processes correctly. Using the modified nucleation theory, an Arrhenius type rate expression is derived to calculate the condensation rate of MgO. This expression can be easily included in the CHEMKIN reaction mechanism format. Although very little property data is available for MgO, the condensation rate expression derived using the existing data is able to capture the condensation of MgO. An appropriate choice of the reference temperature to calculate the rate coefficients allows the model to correctly predict the subsequent heat release and hence the flame temperature.

Abbud-Madrid, A.↗
NASA NTRS1999

Demonstration of an Ultra-Short Channel Metal Monolith Catalytic Reactor for Trace Contaminant Control Applications

The International Space Station (ISS) Trace Contaminant Control Subassembly (TCCS) design is based upon proven, highly reliable technology. However, because its core unit operations rely upon expendable activated charcoal and an indirectly heated high temperature catalyst, annual logistics mass, crew time, and power consumption requirements are significant. To address this situation, a unique catalytic reactor design has been developed which is suitable for retrofit into the TCCS's high temperature catalytic oxidizer (HTCO) assembly. The unique design, which employs a metallic, ultra-short channel length monolith (USCM) catalyst substrate, was tested in a flight-like TCCS HTCO assembly to investigate its performance characteristics. Test results indicate that retrofitting the TCCS with a USCM-based catalytic reactor is feasible and that it may provide significant reductions in logistics mass, crew time, and power consumption. Savings indicated by test results are up to 81% for annual logistics, 56% for crew time, and 77% for startup transient duration. In addition, its demonstrated ability to operate in a power saving mode provides up to a 43% savings in average power consumption. A summary of the USCM demonstration test objectives, approach, results, and specific benefits to the TCCS's process economics are presented,

Perry, J. L↗
DOE OSTI2019

An Asynchronous Real-time Co-simulation Platform for Modeling Interaction between Microgrids and Power Distribution Systems

This paper presents the modeling framework of an asynchronous, real-time co-simulation platform for modeling the interactions between microgrids and power distribution systems. Components of each microgrid are simulated on the OPAL-RT eMEGASIM platform so that electromagnetic transients of the inverter units are modeled at a time step of 100 microseconds. The 3-phase unbalanced distribution feeder that microgrids are connected to is simulated by using the OPAL-RT ePHASORSIM so that load transients, capacitor switching, and tap-changing events can be modeled. A MATLAB-based microgrid controller will interface controllable microgrid components through the Modbus communication. This co-simulation framework allows different microgrid controller logic to be developed and tested on a hardware-in-the-loop testbed considering both the inverter-level transient and the dynamic response of loads and utility equipment. Because the controller communicates with controllable devices via actual communication links, the impact of communication errors, delays, or denial-of-service can also be properly quantified.

Xie, Fuhong↗
DOE OSTI2021

Diagnostic assessment of reservoir response to fracturing: a case study from Hydraulic Fracturing Test Site (HFTS) in Midland Basin

Abstract This paper outlines a data collection and diagnostics case study involving multiple horizontal shale wells. We look at well production profiles using rate transient analysis, differences in near wellbore complexity, geologic variations within the area of interest, as well as compositional differences in the rocks based on cores obtained from within the stimulated reservoir. The Hydraulic Fracturing Test Site is a multi-well experiment involving stimulation of unconventional shale wells in the southeastern Midland portion of the Permian Basin. The targeted formations include both the upper as well as the middle Wolfcamp formations, also referred alternatively as Wolfcamp A and Wolfcamp B. Data integration and analysis shared in this paper help us understand the various geologic controls impacting well productivity, particularly the wide variance observed between the Wolfcamp A and Wolfcamp B formations. Rate transient analysis indicates similar system permeabilities for stimulated wells. However, we observe higher effective fracture half-lengths for upper Wolfcamp wells. Using observations from 3D seismic interpretations (such as pad scale faults) as well as petrophysical and image log data, we highlight the substantial differences in stimulation as we move along the well laterals from the heel toward the toe sections. These differences are further reconciled with observations from zones with high data density at the core locations through stimulated rock, as well as independent data such as microseismic emissions. At the test site, Wolfcamp A was found to be relatively quartz rich with significant heterogeneity whereas Wolfcamp B is richer in clay and organic content. This impacts the geomechanical characteristics of the rock mass with much higher natural fracture density in the shallower interval. Thus, the fracture growth is more uniform in the deeper interval and more heterogeneous with branching likely in upper interval. Increased complexity also leads to consistently better productivity from the wells in the shallower interval as demonstrated from RTA results. This case study is unique because it provides valuable insights from actual sampling of the stimulated zones in hydraulically fractured wells and helps understand impact of various factors that contribute toward variability in well production. The findings from this study provides insights into need for optimization of completion designs in the various Wolfcamp landing zones, such as optimization of cluster or fracture spacing in various Wolfcamp intervals. In addition, it provides a useful template for data collection and research direction in future field test sites of similar nature in unconventional reservoirs.

Energy & Fuels↗
DOE OSTI2017

Pulmonary Arteriovenous Malformations Embolized Using a Micro Vascular Plug System: Technical Note on a Preliminary Experience

AIMTo report our preliminary experience using a Micro Vascular Plug (MVP) deployed through a 2.8Fr micro-catheter for the treatment of pulmonary arteriovenous malformations (PAVMs) in a cohort of patients affected by Hereditary Haemorrhagic Telangiectasia (HHT).Materials and MethodsFour consecutive female patients (mean age 38.0 years; range 25–55 years) with PAVMs diagnosed on echocardiogram/bubble test and contrast-enhanced CT (CECT) underwent MVP embolization. One patient was symptomatic with recent transient ischaemic attack. Follow-up was undertaken at 1-month post-procedure with CECT to assess PAVMs permeability and MVP positioning and at 1-, 6-, and 12-month post-procedure, with echocardiography/bubble test and standard neurological history, to confirm absence of right-to-left shunts and recurrent symptoms.ResultsEight PAVMs were treated in 4 patients over 5 interventional sessions (mean 1.6 PAVMs per session). All PAVMs were simple, with mean feeding artery diameter of 4.25 mm. Eight 6.5 mm MVPs were deployed in total (one per lesion). Technical success was 100%. Mean procedural time and patient dose per session were 70 min (range 40–70 min) and 53418 mGy.cm{sup 2} (range 6113–101628 mGy.cm{sup 2}), respectively. No signs of reperfusion neither of MPV migration were noted at 1-month CECT follow-up. At early follow-up (mean 3.75 months; range 1–12 months), clinical success was 100% with no evidence of recurrent right-to-left shunt, and no neurological symptoms. No immediate or late complications were observed.ConclusionsMVP embolization of PAVMs appears technically feasible, safe, and effective at early follow-up. Further prospective studies are required to confirm long-term safety and efficacy of this promising technique.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
NASA NTRS2023

New Transient Finite Energy Shock Prediction Methodology

Shock prediction is one of the top loads and dynamics discipline technical challenges identified within NASA and industry programs and projects. The physics-based Transient Finite Energy (TFE) shock prediction methodology has been developed and compared favorably against test results. TFE can provide another approach to develop predictions of shock response spectra (SRS) for use in the analysis of structural margins.

NESC Technical Bulletin No. 23-03↗
NASA NTRS2000

Inlet Unstart Propulsion Integration Wind Tunnel Test Program Completed for High-Speed Civil Transport

One of the propulsion system concepts to be considered for the High-Speed Civil Transport (HSCT) is an underwing, dual-propulsion, pod-per-wing installation. Adverse transient phenomena such as engine compressor stall and inlet unstart could severely degrade the performance of one of these propulsion pods. The subsequent loss of thrust and increased drag could cause aircraft stability and control problems that could lead to a catastrophic accident if countermeasures are not in place to anticipate and control these detrimental transient events. Aircraft system engineers must understand what happens during an engine compressor stall and inlet unstart so that they can design effective control systems to avoid and/or alleviate the effects of a propulsion pod engine compressor stall and inlet unstart. The objective of the Inlet Unstart Propulsion Airframe Integration test program was to assess the underwing flow field of a High-Speed Civil Transport propulsion system during an engine compressor stall and subsequent inlet unstart. Experimental research testing was conducted in the 10- by 10-Foot Supersonic Wind Tunnel at the NASA Glenn Research Center at Lewis Field. The representative propulsion pod consisted of a two-dimensional, bifurcated inlet mated to a live turbojet engine. The propulsion pod was mounted below a large flat plate that acted as a wing simulator. Because of the plate s long length (nominally 10-ft wide by 18-ft long), realistic boundary layers could form at the inlet cowl plane. Transient instrumentation was used to document the aerodynamic flow-field conditions during an unstart sequence. Acquiring these data was a significant technical challenge because a typical unstart sequence disrupts the local flow field for about only 50 msec. Flow surface information was acquired via static pressure taps installed in the wing simulator, and intrusive pressure probes were used to acquire flow-field information. These data were extensively analyzed to determine the impact of the unstart transient on the surrounding flow field. This wind tunnel test program was a success, and for the first time, researchers acquired flow-field aerodynamic data during a supersonic propulsion system engine compressor stall and inlet unstart sequence. In addition to obtaining flow-field pressure data, Glenn researchers determined other properties such as the transient flow angle and Mach number. Data are still being reduced, and a comprehensive final report will be released during calendar year 2000.

Porro, A. Robert↗
DOE OSTI2018

Ultrathin Visible-Light-Driven Mo Incorporating In 2 O 3 -ZnIn 2 Se 4 Z-Scheme Nanosheet Photocatalysts

Inspired by natural photosynthesis, the design of new Z-scheme photocatalytic systems is very promising for boosting the photocatalytic performance of H 2 production and CO 2 reduction, however, till now the direct synthesis of efficient Z-scheme photocatalysts remains a grand challenge. Herein, we demonstrate an interesting Z-scheme photocatalyst can be constructed by coupling In 2 O 3 and ZnIn 2 Se 4 semiconductors based on the theoretical calculations. Experimentally, we make a class of ultrathin In 2 O 3 -ZnIn 2 Se 4 (donated as In 2 O 3 -ZISe) spontaneous Z-scheme nanosheet photocatalysts for greatly enhancing the photocatalytic H 2 production. Furthermore, we incorporate Mo atoms to the Z-scheme In 2 O 3 -ZISe nanosheet photocatalyst by forming Mo-Se bond, confirmed by X-Ray photoelectron spectroscopy, in which the formed MoSe 2 works as co-catalyst of Z-scheme photocatalyst. As a consequence, such unique structure of In 2 O 3 -ZISe-Mo makes it exhibit 21.7 and 232.6 times higher photocatalytic H 2 evolution activity than those of In 2 O 3 -ZnIn 2 Se 4 nanosheet and In 2 O 3 nanosheets, respectively. And In 2 O 3 -ZISe-Mo is also very stable for photocatalytic H 2 production by showing almost no activity decay for 16 h test. Here, the ultraviolet-visible diffuse reflectance spectra, photoluminescence spectroscopy, transient photocurrent spectra and electrochemical impedance spectroscopy reveal that the enhanced photocatalytic performance of In 2 O 3 -ZISe-Mo is mainly attributed to its widened photoresponse range and effective carrier separation because of its special structure.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗
DOE OSTI2018

Quench Protection Performance Measurements in the First MQXF Magnet Models

The European Organization for Nuclear Research (CERN) and U.S. LHC Accelerator Research Program (LARP) are jointly developing Nb3Sn quadrupole magnets to be installed in the LHC for its upgrade to higher luminosity. These magnets' quench protection system will include a combination of quench heaters attached to the coil surfaces and coupling-loss-induced quench (CLIQ) units electrically connected to the magnets. Different protection elements have been characterized separately and simultaneously by implementing them on two 1.2-m-long model quadrupole magnets, tested at Fermi National Acceleration Laboratory and CERN, and one 4-m-long mirror magnet tested at Brookhaven Nation Laboratory. After analyzing the test data, their performances have been positively evaluated. Furthermore, the electrothermal transients occurring after a quench have been simulated with the LEDET software and the results are compared to experimental results. The preferred quench protection system configuration relies both on heaters and CLIQ. This solution is based on electrically robust components, achieves an effective reduction of the coils hot spot temperature after a quench, and offers increased redundancy against component failures.

43 PARTICLE ACCELERATORS↗
DOE OSTI2020

Reduced-Order Parameterized Short-Circuit Current Model of Inverter-Interfaced Distributed Generators

The short-circuit response of inverter-interfaced distributed generators (IIDGs) is not adequately represented in many conventional protection studies. This paper presents an in-depth analysis of IIDG behavior during grid faults and proposes a more accurate reduced-order parameterized short-circuit current (RPSC) model of inverters. Typical inverter components are thoroughly investigated to identify those that play dominant roles during faults. The paper shows that the current limiter is the dominant factor for the steady-state fault-current of inverter; while the inverter filter along with the severity of the voltage disturbance largely determine the initial transient spike of inverter fault current. The proposed model is low-order and can be used in large scale simulations. The parameters of the proposed RPSC model can be extracted from laboratory experiments without requiring proprietary manufacturer information. The proposed fault-current model is analogous to the well-known synchronous machine model that segregates the inverter fault current into subtransient, transient, and steady-state fault currents. Finally, experimental and simulation tests are presented to validate the model.

24 POWER TRANSMISSION AND DISTRIBUTION↗
DOE OSTI2025

Refabriation of HERA-HBU-2, LOC-HBU-1, and LOC-HBU-2

The development of advanced fuels for Light Water Reactors (LWRs) is essential for improved fuel performance and safety, including performance margins, uprates, and higher burnup. Because available commercial LWR fuels often cannot be used in research reactors, the refabrication of preirradiated fuel is necessary to enable follow-on testing of these fuels for characterizing fuel behavior during steady and transient irradiations.

11 - NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗
NASA NTRS1981

Blade loss transient dynamics analysis, volume 2. Task 2: Theoretical and analytical development. Task 3: Experimental verification

The component element method was used to develop a transient dynamic analysis computer program which is essentially based on modal synthesis combined with a central, finite difference, numerical integration scheme. The methodology leads to a modular or building-block technique that is amenable to computer programming. To verify the analytical method, turbine engine transient response analysis (TETRA), was applied to two blade-out test vehicles that had been previously instrumented and tested. Comparison of the time dependent test data with those predicted by TETRA led to recommendations for refinement or extension of the analytical method to improve its accuracy and overcome its shortcomings. The development of working equations, their discretization, numerical solution scheme, the modular concept of engine modelling, the program logical structure and some illustrated results are discussed. The blade-loss test vehicles (rig full engine), the type of measured data, and the engine structural model are described.

Gallardo, V. C.↗
NASA NTRS1981

Capillary priming characteristics of a dual passage heat pipe in zero-g

Technical improvements of a long life heat rejection system, suitable for long duration high power missions, that can be constructed and deployed in orbit is discussed. A mathematical model is formulated and a computer program developed which describes the transient priming characteristics of a dual passage heat pipe. An experimental test package is described for flight in the KC-135 Zero-g Aircraft, to be used to verify the modeling predictions.

Peterson, G. P.↗