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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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Combining the quasi-static loads, workmanship verification, and model validation tests of aerospace hardware into a single vibration test sequence can considerably reduce schedule and cost.
A diagnostic tool was developed for detecting fatigue damage of tapered roller bearings. Tapered roller bearings are used in helicopter transmissions and have potential for use in high bypass advanced gas turbine aircraft engines. A diagnostic tool was developed and evaluated experimentally by collecting oil debris data from failure progression tests conducted using health monitoring hardware. Failure progression tests were performed with tapered roller bearings under simulated engine load conditions. Tests were performed on one healthy bearing and three pre-damaged bearings. During each test, data from an on-line, in-line, inductance type oil debris sensor and three accelerometers were monitored and recorded for the occurrence of bearing failure. The bearing was removed and inspected periodically for damage progression throughout testing. Using data fusion techniques, two different monitoring technologies, oil debris analysis and vibration, were integrated into a health monitoring system for detecting bearing surface fatigue pitting damage. The data fusion diagnostic tool was evaluated during bearing failure progression tests under simulated engine load conditions. This integrated system showed improved detection of fatigue damage and health assessment of the tapered roller bearings as compared to using individual health monitoring technologies.
White Sands Test Facility Core Capabilities: a) Remote Hazardous Testing of Reactive, Explosive, and Toxic Materials and Fluids; b) Hypergolic Fluids Materials and Systems Testing; c) Oxygen Materials and System Testing; d) Hypervelocity Impact Testing; e)Flight Hardware Processing; and e) Propulsion Testing. There is no impact to any drinking water well. Includes public wells and the NASA supply well. There is no public exposure. Groundwater is several hundred feet below ground. No air or surface water exposure. Plume is moving very slowly to the west. Plume Front Treatment system will stop this westward movement. NASA performs on-going monitoring. More than 200 wells and zones are routinely sampled. Approx. 850 samples are obtained monthly and analyzed for over 300 different hazardous chemicals.
The National Aeronautics and Space Administration's (NASA's) Desert Research and Technology Studies (Desert RATS) is a multi-year series of tests of hardware and operations carried out annually in the high desert of Arizona, as an analog to future exploration activities beyond low Earth orbit [1]. For the past several years, these tests have occurred in the San Francisco Volcanic Field, north of Flagstaff. For the 2011 Desert RATS season, the Exploration Systems Mission Directorate (ESMD) at NASA headquarters provided support to develop an education pilot project that would include student activities to parallel the Desert RATS mission planning and exploration activities in the classroom, and educator training sessions. The development of the pilot project was a joint effort between the NASA Johnson Space Center (JSC) Astromaterials Research and Exploration Science (ARES) Directorate and the Aerospace Education Services Project (AESP), managed at Penn State University.
This paper evaluates an existing protection scheme implemented in a real-world weak grid area with a high penetration of inverter-based resources (IBRs). The study aims to assess the reliability and adequacy of protection schemes originally designed for traditional synchronous machine systems and determine whether they can continue to operate reliably in systems with high levels of IBRs. Hardware relays are tested using a controller-hardware-in-the-loop setup. PSCAD electromagnetic transient simulation with an IBR original equipment manufacturer black-box model is used to perform fault studies and generate COMTRADE data, which are replayed by a real-time digital simulator (RTDS) to feed input to the hardware relays. Three scenarios are analyzed: normal operation, an N-1 contingency, and an IBR-only scenario. The evaluation results reveal the following: 1) the protection scheme remains reliable under normal conditions and N-1 contingencies and 2) in IBR-only scenarios, differential protection (87L) continues to operate reliably, whereas local protection elements, such as distance and directional elements, fail because of the lack of regulated negative sequence current contributed by IBRs. These findings provide utilities with valuable insights for improving their protection systems in high-IBRs.
This special publication tells the story of the dedicated efforts of very talented individuals to create a preeminent space electrical power system modeling and simulation tool called SPACE, short for System Power Analysis for Capability Evaluation. This computer model has evolved for 30 years, withstanding the test of time and obsolescence, and garnering international recognition for its ability to simulate complex space electrical power systems. The analytical results from this model have saved millions of dollars in hardware redesign, testing, and verification for NASA's International Space Station (ISS) and its European and Russian partners. SPACE has played a pivotal role in the station's design and development and continues to support its ongoing operation. It has also extended its reach beyond the ISS to other key NASA programs, where it guides the design and planned operation of NASA's Multi-Purpose Crew Vehicle Orion and simulates electric power system operation in a dusty atmosphere on Mars' surface. The SPACE lineage was created by a core civil servant staff, supplemented by a cadre of interns and other temporary helpers. They created a tightly integrated tool that includes all phenomena that impact a solar array and battery space power system performance. SPACE is self-contained, requiring no other software modules and associated license fees. SPACE "rings true" in that is has been extensively validated with ISS on-orbit telemetry data. This report is being released as the generation of engineers who created it are nearing retirement, passing the baton to a new generation. This next generation will carry the code into the future, no doubt further evolving it to be able to assure mission planners that newly conceived systems will successfully power NASA's next endeavors. As a previous SPACE code developer and analyst, I have worked alongside many of the people mentioned in this report. The engineers who created the code, along with those just now learning it, are among the best and brightest at NASA. It is an honor to write this foreword as the present Branch Chief under which the legacy of SPACE continues to thrive.
NASA is planning its next step toward human expansion into the solar system. The Space Launch System (SLS) (Figure 1) is a critical enabling component of that expansion. SLS payloads for its early missions include the Orion crew vehicle and components for Gateway, a lunar outpost orbiting the Moon that will facilitate research, technology and partnerships for eventual Mars missions. All major core stage hardware for test and flight completed structural manufacturing in 2018. The major components for the first flight vehicle are complete or approaching completion of internal equipment installation. The core stage forward join operation is also complete. The 10 booster segments needed for first flight have been cast and are ready to ship to NASA’s Kennedy Space Center (KSC) for mating and stacking. The four RS-25 core stage engines completed processing at NASA’s Stennis Space Center (SSC) and are ready for core stage integration. The Orion Stage Adapter (OSA) joined the Interim Cryogenic Propulsion Stage (ICPS) at KSC to await the rest of SLS flight hardware. Production and preparation of hardware for the second mission is also underway. Looking ahead to a busy 2019, liquid oxygen (LOX) tank, liquid hydrogen (LH2) tank and intertank structural testing will take place. This paper will discuss the current and planned status of SLS development in context of NASA’s overall exploration plans.
The International Space Station (ISS) presents a significant acoustics challenge considering all of the Modules and equipment that make it an on-orbit laboratory workshop and home with long-term crew occupation. This challenge is further complicated by the fact there are numerous and a wide variety suppliers of Station hardware, including International Partners. This paper addresses how ISS acoustics are managed to ensure a safe and habitable environment by establishing requirements, providing oversight and design support, sharing lessons learned and information, testing for hardware compliance, predicting future acoustic levels, and performing on-orbit measurement and monitoring of actual acoustic levels. ISS acoustic requirements are classified by the type of hardware involved, in three categories: Modules; payloads; and Government Furnished Equipment (GFE). Current status of overall ISS acoustics for each of these hardware categories will be discussed. In addition, the following items will be discussed: examples where NASA design support has been used to aid in obtaining compliance; difficulties encountered; and areas of concern.
The Transiting Exoplanet Survey Satellite (TESS) is a NASA Explorer mission. The TESS Observatory is scheduled to launch on Falcon 9 in April 2018. This presentation covers the process used to define and update design limit loads for the observatory, instrument, and components throughout the life of the program. The limit loads that drove the need for a SoftRide isolation system are highlighted. The testing performed to qualify the observatory for launch loads at the instrument and observatory level is also detailed. In addition, exchanges with the launch vehicle provider in terms of loads predictions and hardware for test are discussed along with the associated issues encountered and lessons learned. The loads development and verification success on TESS was a team effort. Orbital ATK is the spacecraft provider, NASA GSFC provides project management and technical oversight, the instrument is managed by MIT Kavli Institute and the instrument cameras are built and tested by MIT Lincoln Laboratory. Since the instrument was designed in parallel with the spacecraft, the instrument design limit loads were developed in partnership with NASA and the instrument team. The three teams collaborated on a regular basis starting in the early design phase and continuing through observatory level testing.
The NASA Glenn Research Center is working with the aeronautics industry to develop highly fuel-efficient and environmentally friendly gas turbine combustor technology. This effort includes testing new hardware designs at conditions that simulate the high-temperature, high-pressure environment expected in the next-generation of high-performance engines. Glenn has the only facilities in which such tests can be performed. One aspect of these tests is the use of nonintrusive optical and laser diagnostics to measure combustion species concentration, fuel/air ratio, fuel drop size, and velocity, and to visualize the fuel injector spray pattern and some combustion species distributions. These data not only help designers to determine the efficacy of specific designs, but provide a database for computer modelers and enhance our understanding of the many processes that take place within a combustor. Until recently, we lacked one critical capability, the ability to measure temperature. This article summarizes our latest developments in that area. Recently, we demonstrated the first-ever use of spontaneous Raman scattering to measure combustion temperatures within the Advanced Subsonics Combustion Rig (ASCR) sector rig. We also established the highest rig pressure ever achieved for a continuous-flow combustor facility, 54.4 bar. The ASCR facility can provide operating pressures from 1 to 60 bar (60 atm). This photograph shows the Raman system setup next to the ASCR rig. The test was performed using a NASA-concept fuel injector and Jet-A fuel over a range of air inlet temperatures, pressures, and fuel/air ratios.
An overview of the facilities and research being conducted at LeRC's Plumbrook field station is given. The video highlights four main structures and explains their uses. The Space Power Facility is the world's largest space environment simulation chamber, where spacebound hardware is tested in simulations of the vacuum and extreme heat and cold of the space plasma environment. This facility was used to prepare Atlas 1 rockets to ferry CRRES into orbit; it will also be used to test space nuclear electric power generation systems. The Spacecraft Propulsion Research Facility allows rocket vehicles to be hot fired in a simulated space environment. In the Cryogenic Propellant Tank Facility, researchers are developing technology for storing and transferring liquid hydrogen in space. There is also a Hypersonic Wind Tunnel which can perform flow tests with winds up to Mach 7.
The NASA White Sands Test Facility (WSTF) has developed an entirely aqueous final cleaning and verification process to replace the current chlorofluorocarbon (CFC) 113 based process. This process has been accepted for final cleaning and cleanliness verification of WSTF ground support equipment. The aqueous process relies on ultrapure water at 50 C (323 K) and ultrasonic agitation for removal of organic compounds and particulate. The cleanliness is verified bv determining the total organic carbon (TOC) content and filtration with particulate counting. The effectiveness of the aqueous methods for detecting hydrocarbon contamination and particulate was compared to the accepted CFC 113 sampling procedures. Testing with known contaminants, such as hydraulic fluid and cutting and lubricating oils, to establish a correlation between aqueous TOC and CFC 113 nonvolatile residue (NVR) was performed. Particulate sampling on cleaned batches of hardware that were randomly separated and sampled by the two methods was performed. This paper presents the approach and results, and discusses the issues in establishing the equivalence of aqueous sampling to CFC 113 sampling, while describing the approach for implementing aqueous techniques on Space Shuttle Propulsion hardware.
The paper presents the hardware implementation and initial tests from a low-power, highspeed reconfigurable sensor fusion processor. The Extended Logic Intelligent Processing System (ELIPS) is described, which combines rule-based systems, fuzzy logic, and neural networks to achieve parallel fusion of sensor signals in compact low power VLSI. The development of the ELIPS concept is being done to demonstrate the interceptor functionality which particularly underlines the high speed and low power requirements. The hardware programmability allows the processor to reconfigure into different machines, taking the most efficient hardware implementation during each phase of information processing. Processing speeds of microseconds have been demonstrated using our test hardware.
The integrated starter-generator system (ISGS) is a combination of starter and generator for independent power systems in transportation. It replaces both a conventional starter and generator with a single set of highly integrated devices. A power hardware in the loop simulation that is flexible and can include the hardware under test is used to test the ISGS under representative field conditions. This paper utilizes the special structure of the ISGS and proposes an ISGS emulator (ISGSE) to develop and test the converter. The proposed ISGSE can be used to test a variety of motor drives or rectifiers including dynamic capabilities without necessitating a connection to a large motor load. To emulate the ISGS, the structure and operation principle in different modes are introduced in detail. Also, the issue of stability and accuracy is discussed in this paper. Furthermore, detailed simulation and experimental comparisons are carried out between the ISGS and the ISGSE, which validates the proposed ISGSE as an effective tool for designing and testing new motor drives.
Identify, test and develop qualification criteria for environmentally friendly corrosion protective coatings and corrosion preventative compounds (CPC's) for flight hardware an ground support equipment.
The objective was to apply powder metallurgy techniques for the production of improved bearing elements, specifically balls and races, for advanced cryogenic turbopump bearings. The materials and fabrication techniques evaluated were judged on the basis of their ability to improve fatigue life, wear resistance, and corrosion resistance of Space Shuttle Main Engine (SSME) propellant bearings over the currently used 440C. An extensive list of candidate bearing alloys in five different categories was considered: tool/die steels, through hardened stainless steels, cobalt-base alloys, and gear steels. Testing of alloys for final consideration included hardness, rolling contact fatigue, cross cylinder wear, elevated temperature wear, room and cryogenic fracture toughness, stress corrosion cracking, and five-ball (rolling-sliding element) testing. Results of the program indicated two alloys that showed promise for improved bearing elements. These alloys were MRC-2001 and X-405. 57mm bearings were fabricated from the MRC-2001 alloy for further actual hardware rig testing by NASA-MSFC.
Under sponsorship of the NASA Glenn Research Center (NASA GRC), the Johns Hopkins University Applied Physics Laboratory (JHU/APL) designed and built a five-inch diameter, Rocket-Based Combined Cycle (RBCC) engine to investigate mode 1 and mode 4 engine performance as well as Mach 4 inlet performance. This engine was designed so that engine area and length ratios were similar to the NASA GRC GTX engine is shown. Unlike the GTX semi-circular engine design, the APL engine is completely axisymmetric. For this design, a traditional rocket thruster was installed inside of the scramjet flowpath, along the engine centerline. A three part test series was conducted to determine Mode I and Mode 4 engine performance. In part one, testing of the rocket thruster alone was accomplished and its performance determined (average Isp efficiency = 90%). In part two, Mode 1 (air-augmented rocket) testing was conducted at a nominal chamber pressure-to-ambient pressure ratio of 100 with the engine inlet fully open. Results showed that there was neither a thrust increment nor decrement over rocket-only thrust during Mode 1 operation. In part three, Mode 4 testing was conducted with chamber pressure-to-ambient pressure ratios lower than desired (80 instead of 600) with the inlet fully closed. Results for this testing showed a performance decrease of 20% as compared to the rocket-only testing. It is felt that these results are directly related to the low pressure ratio tested and not the engine design. During this program, Mach 4 inlet testing was also conducted. For these tests, a moveable centerbody was tested to determine the maximum contraction ratio for the engine design. The experimental results agreed with CFD results conducted by NASA GRC, showing a maximum geometric contraction ratio of approximately 10.5. This report details the hardware design, test setup, experimental results and data analysis associated with the aforementioned tests.
The unique combination of adaptive wall technology with a continuous flow cryogenic wind tunnel is described. This powerful combination allows wind tunnel users to carry out two-dimensional (2-D) tests at flight Reynolds numbers with wall interferences essentially eliminated. Validation testing was conducted to support this claim using well tested symmetrical and cambered airfoils at transonic speeds and high Reynolds numbers. The test section hardware has four solid walls, with the floor and ceiling flexible. The method of adapting/shaping the floor and ceiling to eliminate top and bottom wall interference at its source is outlined. Data comparisons for different size models tested and others in several sophisticated 2-D wind tunnels are made. In addition, the effects of Reynolds number, testing at high lift with associated large flexible wall movements, the uniqueness of the adapted wall shapes, and the effects of sidewall boundary layer control are examined. The 0.3-m TCT is now the most advanced 2-D research facility anywhere.