Search NASA⌕ Search

SEARCH · Search NASA

Results for “integrated testing”

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 1,585 records · Page 88

An integrated knowledge system for wind tunnel testing - Project Engineers' Intelligent Assistant

The Project Engineers' Intelligent Assistant (PEIA) is an integrated knowledge system developed using artificial intelligence technology, including hypertext, expert systems, and dynamic user interfaces. This system integrates documents, engineering codes, databases, and knowledge from domain experts into an enriched hypermedia environment and was designed to assist project engineers in planning and conducting wind tunnel tests. PEIA is a modular system which consists of an intelligent user-interface, seven modules and an integrated tool facility. Hypermedia technology is discussed and the seven PEIA modules are described. System maintenance and updating is very easy due to the modular structure and the integrated tool facility provides user access to commercial software shells for documentation, reporting, or database updating. PEIA is expected to provide project engineers with technical information, increase efficiency and productivity, and provide a realistic tool for personnel training.

Lo, Ching F.↗

Overview of Heatshield for Extreme Entry Environment Technology (HEEET) Engineering Test Unit (ETU) Manufacturing and Integration

The Heatshield for Extreme Entry Environment Technology (HEEET) projects objective is to mature a 3-D Woven Thermal Protection System (TPS) to Technical Readiness Level (TRL) 6 to support future NASA missions to destinations such as Venus and Saturn. A key aspect of the project has been the development of the manufacturing and integration processes/procedures necessary to build a heat shield utilizing the HEEET 3D-woven material. This has culminated in the building of a 1meter diameter Engineering Test Unit (ETU) representative of what would be used for a Saturn probe. This presentation will provide an overview of the manufacturing and integration processes utilized to build the ETU, with a focus on the seam design. The seam design represented the most challenging aspect of the HEEET development, given the aerothermal and structural requirements it needs to meet.

Thermal Protection System↗

Realistic operation of two residential cordwood-fired outdoor hydronic heater appliances—Part 1: Particulate and gaseous emissions

This study investigated how heat demand and fuel loading affect the emissions from outdoor wood-fired hydronic heaters by testing two such appliances using an integrated-duty cycle test method. This test included transient operating conditions, such as cold and hot-starts and modulation between 15 and 100% of maximum rated output. Emission values indicate transient operating conditions produce higher emissions than steady state operation. Cold starts resulted in elevated particulate matter emission factors for both appliances; in one case the particulate matter emission factor for this period was >3500 mg/MJ, which represented emissions 20 times the average value. Additionally, when heat demand was cycled—elevated CO emission factors were measured, with values >5000 mg/MJ for both appliances and more than 3 times the appliance averages, respectively. It follows that the appliance average particulate matter emission factors and CO emission factors were not representative of the actual EF values during these transient periods. In contrast, methane emission factors were relatively stable throughout all tested combustion conditions; however, they were much higher than oil-fired appliances are therefore should not be ignored. These findings demonstrate that wood-fired hydronic heater emissions during transient operating conditions can be significantly greater than emissions during steady-state test conditions, such as those used in typical certification tests. Consequently, certification test values for particulate matter and CO emission factors may significantly underestimate the actual emissions of these appliances when operated in a home. Use of integrated duty-cycle test protocols that capture cold-starts and reloading are better for representing in-use operations of wood-fired hydronic heaters and provide more realistic emissions and delivered efficiency measurements.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗

Integrated Avionics System (IAS)

As spacecraft designs converge toward miniaturization and with the volumetric and mass constraints placed on avionics, programs will continue to advance the 'state of the art' in spacecraft systems development with new challenges to reduce power, mass, and volume. Although new technologies have improved packaging densities, a total system packaging architecture is required that not only reduces spacecraft volume and mass budgets, but increase integration efficiencies, provide modularity and scalability to accommodate multiple missions. With these challenges in mind, a novel packaging approach incorporates solutions that provide broader environmental applications, more flexible system interconnectivity, scalability, and simplified assembly test and integration schemes. This paper will describe the fundamental elements of the Integrated Avionics System (IAS), Horizontally Mounted Cube (HMC) hardware design, system and environmental test results. Additional information is contained in the original extended abstract.

Hunter, D. J.↗

Flight Test Experience With an Electromechanical Actuator on the F-18 Systems Research Aircraft

Development of reliable power-by-wire actuation systems for both aeronautical and space applications has been sought recently to eliminate hydraulic systems from aircraft and spacecraft and thus improve safety, efficiency, reliability, and maintainability. The Electrically Powered Actuation Design (EPAD) program was a joint effort between the Air Force, Navy, and NASA to develop and fly a series of actuators validating power-by-wire actuation technology on a primary flight control surface of a tactical aircraft. To achieve this goal, each of the EPAD actuators was installed in place of the standard hydraulic actuator on the left aileron of the NASA F/A-18B Systems Research Aircraft (SRA) and flown throughout the SRA flight envelope. Numerous parameters were recorded, and overall actuator performance was compared with the performance of the standard hydraulic actuator on the opposite wing. This paper discusses the integration and testing of the EPAD electromechanical actuator (EMA) on the SRA. The architecture of the EMA system is discussed, as well as its integration with the F/A-18 Flight Control System. The flight test program is described, and actuator performance is shown to be very close to that of the standard hydraulic actuator it replaced. Lessons learned during this program are presented and discussed, as well as suggestions for future research.

Jensen, Stephen C.↗

Flight Test Experience with an Electromechanical Actuator on the F-18 Systems Research Aircraft

Development of reliable power-by-wire actuation systems for both aeronautical and space applications has been sought recently to eliminate hydraulic systems from aircraft and spacecraft and thus improve safety, efficiency, reliability, and maintainability. The Electrically Powered Actuation Design (EPAD) program was a joint effort between the Air Force, Navy, and NASA to develop and fly a series of actuators validating power-by-wire actuation technology on a primary flight control surface of a tactical aircraft. To achieve this goal, each of the EPAD actuators was installed in place of the standard hydraulic actuator on the left aileron of the NASA F/A-18B Systems Research Aircraft (SRA) and flown throughout the SRA flight envelope. Numerous parameters were recorded, and overall actuator performance was compared with the performance of the standard hydraulic actuator on the opposite wing. This paper discusses the integration and testing of the EPAD electromechanical actuator (EMA) on the SRA. The architecture of the EMA system is discussed, as well as its integration with the F/A-18 Flight Control System. The flight test program is described, and actuator performance is shown to be very close to that of the standard hydraulic actuator it replaced. Lessons learned during this program are presented and discussed, as well as suggestions for future research.

Jensen, Stephen C.↗

Advancement of Miniature Optic Gas Sensor (MOGS) Probe Technology

Advancement of Miniature Optic Gas Sensor (MOGS) Probe Technology" project will investigate newly developed optic gas sensors delivered from a Small Business Innovative Research (SBIR) Phase II effort. A ventilation test rig will be designed and fabricated to test the sensors while integrated with a Suited Manikin Test Apparatus (SMTA). Once the sensors are integrated, a series of test points will be completed to verify that the sensors can withstand Advanced Suit Portable Life Support System (PLSS) environments and associated human metabolic profiles for changes in pressure and levels of Oxygen (ppO2), carbon dioxide (ppCO2), and humidity (ppH2O).

Chullen, Cinda↗

Torsional Vibration in the National Wind Technology Center’s 2.5-Megawatt Dynamometer

This report documents the torsional drivetrain dynamics of the NWTC's 2.5-megawatt dynamometer as identified experimentally and as calculated using lumped parameter models using known inertia and stiffness parameters. The report is presented in two parts beginning with the identification of the primary torsional modes followed by the investigation of approaches to damp the torsional vibrations. The key mechanical parameters for the lumped parameter models and justification for the element grouping used in the derivation of the torsional modes are presented. The sensitivities of the torsional modes to different test article properties are discussed. The oscillations observed from the low-speed and generator torque measurements were used to identify the extent of damping inherently achieved through active and passive compensation techniques. A simplified Simulink model of the dynamometer test article integrating the electro-mechanical power conversion and control features was established to emulate the torque behavior that was observed during testing. The torque response in the high-speed, low-speed, and generator shafts were tested and validated against experimental measurements involving step changes in load with the dynamometer operating under speed-regulation mode. The Simulink model serves as a ready reference to identify the torque sensitivities to various system parameters and to explore opportunities to improve torsional damping under different conditions.

17 WIND ENERGY↗

Mini-99 Experiment Design and Target Assembly

Qualification of nuclear fuels requires an understanding of a myriad of fuel performance variables, which requires time-consuming irradiations in test reactors. Accelerating burnup accumulation to reduce the irradiation time has historically been accomplished by increasing the 235 U enrichment in integral fuel tests, which inherently couples the fuel’s temperature and fission heat generation. Separate effects irradiation testing of nuclear fuel, using the MiniFuel target in the Oak Ridge National Laboratory’s (ORNL’s) High Flux Isotope Reactor (HFIR), offers an approach for decoupling fuel temperature and fission rate by reducing the quantity of the fuel and relying primarily on gamma heating in the surrounding components to drive fuel temperatures. However, if the fission rate is high enough, the fuel temperature will still vary over time as the fission heating changes, primarily due to poor heat conduction between the fuel and the surrounding components. This work details the design, analysis, and fabrication of a MiniFuel target which utilizes sodium bonding to improve the heat rejection from the fuel specimen, enabling the testing of higher 235 U enrichments (~8wt.%) to further accelerate burnup accumulation without prohibitively large temperature variations throughout the course of the irradiation.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗

Compatibility experiments of facilities, materials, and propellants for electrothermal thrusters

Experiments were performed to determine the compatibility of materials and propellants for electro-thermal thrusters. Candidate propellants for resistojet propulsion include carbon dioxide, methane, hydrogen, ammonia, and hydrazine. The materials being examined are grain stabilized platinum for resistojets for Space station and rhenium for high performance resistojets for satellites. Heater mass loss and deterioration of materials were evaluated. A coiled tube of platinum, with yttria dispersed throughout the base material to inhibit grain growth, was tested in carbon dioxide at 1300 C for 2000 hr. Post-test examination indicated the platinum-yttria heater would last over 100 000 hr with less than 10 percent mass loss. Short-term compatibility tests were conducted to test the integrity of the platinum-yttria in hydrogen, methane, carbon dioxide/methane mixtures and ammonia environments. In each of these 100 hr tests, the platinum-yttria mass change indicated a minimum coil life of 100 000 hr. Facility related effects were investigated in materials tests using rhenium heated to high tempertures. Vacuum facility water reduction was monitored using a mass spectrometer. In vacuum environments obtained using only diffusion pumping and those obtained with the assistance of cryogenic equipment there were mass gains in the rhenium heaters. These mass gains were the result of the high amount of oxygen and water contained in the gas. Propellant purity and preferred test facility environments are discussed.

Whalen, M. V.↗

Compatibility experiments of facilities, materials, and propellants for electrothermal thrusters

Experiments were performed to determine the compatibility of materials and propellants for electro-thermal thrusters. Candidate propellants for resistojet propulsion include carbon dioxide, methane, hydrogen, ammonia, and hydrazine. The materials being examined are grain stabilized platinum for resistojets for space station and rhenium for high performance resistojets for satellites. Heater mass loss and deterioration of materials were evaluated. A coiled tube of platinum, with yttria dispersed throughout the base material to inhibit grain growth, was tested in carbon dioxide at 1300 C for 2000 hr. Post-test examination indicated the platinum-yttria heater would last over 100,000 hr with less than 10 percent mass loss. Short-term compatibility tests were conducted to test the integrity of the platinum-yttria in hydrogen, methane, carbon dioxide/methane mixtures and ammonia environments. In each of these 100 hr tests, the platinum-yttria mass change indicated a minimum coil life of 100,000 hr. Facility related effects were investigated in materials tests using rhenium heated to high temperatures. Vacuum facility water reduction was monitored using a mass spectrometer. In vacuum environments obtained using only diffusion pumping and those obtained with the assistance of cryogenic equipment there were mass gains in the rhenium heaters. These mass gains were the result of the high amount of oxygen and water contained in the gas. Propellant purity and preferred test facility environments are discussed.

Whalen, M. V.↗

Mass analysis addition to the Differential Ion Flux Probe (DIFP) study

The objective of this study is to develop a technique to measure the characteristics of space plasmas under highly disturbed conditions; e.g., non-Maxwellian plasmas with strong drifting populations and plasmas contaminated by spacecraft outgassing. The approach, conducted in conjunction with current MSFC activities, is to extend the capabilities of the Differential Ion Flux Probe (DIFP) to include a high throughput mass measurement that does not require either high voltage or contamination sensitive devices such as channeltron electron multipliers or microchannel plates. This will significantly reduce the complexity and expense of instrument fabrication, testing, and integration of flight hardware compared to classical mass analyzers. The feasibility of the enhanced DIFP has been verified by using breadboard test models in a controlled plasma environment. The ability to manipulate particles through the instrument regardless of incident angle, energy, or ionic component has been amply demonstrated. The energy analysis mode is differential and leads directly to a time-of-flight mass measurement. With the new design, the DIFP will separate multiple ion streams and analyze each stream independently for ion flux intensity, velocity (including direction of motion), mass, and temperature (or energy distribution). In particular, such an instrument will be invaluable on follow-on electrodynamic TSS missions and, possibly, for environmental monitoring on the space station.

Wright, K. H., Jr.↗

COBALT CoOperative Blending of Autonomous Landing Technology

COBALT is a terrestrial test platform for development and maturation of GN&C (Guidance, Navigation and Control) technologies for PL&HA (Precision Landing and Hazard Avoidance). The project is developing a third generation, Langley Navigation Doppler Lidar (NDL) for ultra-precise velocity and range measurements, which will be integrated and tested with the JPL Lander Vision System (LVS) for Terrain Relative Navigation (TRN) position estimates. These technologies together provide navigation that enables controlled precision landing. The COBALT hardware will be integrated in 2017 into the GN&C subsystem of the Xodiac rocket-propulsive Vertical Test Bed (VTB) developed by Masten Space Systems (MSS), and two terrestrial flight campaigns will be conducted: one open-loop (i.e., passive) and one closed-loop (i.e., active).

Carson, John M. III↗

Cobalt: Development and Maturation of GN&C Technologies for Precision Landing

The CoOperative Blending of Autonomous Landing Technologies (COBALT) instrument is a terrestrial test platform for development and maturation of guidance, navigation and control (GN&C) technologies for precision landing. The project is developing a third-generation Langley Research Center (LaRC) navigation doppler lidar (NDL) for ultra-precise velocity and range measurements, which will be integrated and tested with the Jet Propulsion Laboratory (JPL) lander vision system (LVS) for terrain relative navigation (TRN) position estimates. These technologies together provide precise navigation knowledge that is critical for a controlled and precise touchdown. The COBALT hardware will be integrated in 2017 into the GN&C subsystem of the Xodiac rocket-propulsive vertical test bed (VTB) developed by Masten Space Systems, and two terrestrial flight campaigns will be conducted: one open-loop (i.e., passive) and one closed-loop (i.e., active).

Carson, John M.↗

Roadmap for IES Modeling and Simulation Activities: Update 2023

Since inception of the DOE-NE Integrated Energy Systems (IES) program, several program and modeling visions and roadmaps have been published. In 2020, a last comprehensive roadmap for the DOE-NE Integrated Energy Systems program was published. In 2017, a separate modeling and simulation capability development plan was published that was extensively updated in 2022. The current report incrementally updates the 2022 modeling and simulation capability roadmap. This is not a new report, but individual sections have been updated to reflect recent accomplishments and new directions of the program. The role of modeling and simulation within IES is to support the demonstration of new coupled integrated technologies along every step of the technology maturation from the strategic analysis of preferred system architecture to preliminary design, to laboratory testing, up to full commercial testing and integration. To achieve this role, modeling and simulation must be able to assess the technical performance and the economic viability of potential IES. Also, modeling and simulation must provide support for experimental evaluations (i.e., support component design and real-time operations of experimental demonstration systems). Finally, modeling and simulation can help scale-up experimental systems to the final commercial systems. This report details the current state of the modeling and simulation efforts within IES for the above-mentioned areas, provides a gap analysis, and proposes next steps for a time horizon over the next years.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗

Real-time flight test analysis and display techniques for the X-29A aircraft

The X-29A advanced technology demonstrator flight envelope expansion program and the subsequent flight research phase gave impetus to the development of several innovative real-time analysis and display techniques. These new techniques produced significant improvements in flight test productivity, flight research capabilities, and flight safety. These techniques include real-time measurement and display of in-flight structural loads, dynamic structural mode frequency and damping, flight control system dynamic stability and control response, aeroperformance drag polars, and aircraft specific excess power. Several of these analysis techniques also provided for direct comparisons of flight-measured results with analytical predictions. The aeroperformance technique was made possible by the concurrent development of a new simplified in-flight net thrust computation method. To achieve these levels of on-line flight test analysis, integration of ground and airborne systems was required. The capability of NASA Ames Research Center, Dryden Flight Research Facility's Western Aeronautical Test Range was a key factor in enabling implementation of these methods.

Hicks, John W.↗