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Limited flight - test data obtained from an automatically controlled interceptor during runs in which oscillatory rolling motions were encountered have been correlated with the pilot's comments regarding his ability to tolerate the imposed lateral accelerations.
Finite element analyses have been performed for two full-scale crash tests of an MD-500 helicopter. The first crash test was conducted to evaluate the performance of a composite deployable energy absorber under combined flight loads. In the second crash test, the energy absorber was removed to establish the baseline loads. The use of an energy absorbing device reduced the impact acceleration levels by a factor of three. Accelerations and kinematic data collected from the crash tests were compared to analytical results. Details of the full-scale crash tests and development of the system-integrated finite element model are briefly described along with direct comparisons of acceleration magnitudes and durations for the first full-scale crash test. Because load levels were significantly different between tests, models developed for the purposes of predicting the overall system response with external energy absorbers were not adequate under more severe conditions seen in the second crash test. Relative error comparisons were inadequate to guide model calibration. A newly developed model calibration approach that includes uncertainty estimation, parameter sensitivity, impact shape orthogonality, and numerical optimization was used for the second full-scale crash test. The calibrated parameter set reduced 2-norm prediction error by 51% but did not improve impact shape orthogonality.
Vehicles were characterized for the state of the art assessment of electric vehicles. The vehicle evaluated was a Chevrolet Corvette converted to electric operation. The original internal combustion engine was replaced by an electric traction motor. Eighteen batteries supplied the electrical energy. A controller, an onboard battery charger, and several dashboard instruments completed the conversion. The emphasis was on the electrical portion of the drive train, although some analysis and discussion of the mechanical elements are included. Tests were conducted both on the road (actually a mile long runway) and in a chassis dynamometer equipped laboratory. The majority of the tests performed were according to SAE Procedure J227a and included maximum effort accelerations, constant speed range, and cyclic range. Some tests that are not a part of the SAE Procedure J227a are described and the analysis of the data from all tests is discussed.
The purpose of the NASA Langley Airborne Spacing for Terminal Arrival Routes (ASTAR) research aboard the Boeing ecoDemonstrator aircraft was to demonstrate the use of NASA's ASTAR algorithm using contemporary tools of the Federal Aviation Administration's Next Generation Air Transportation System (NEXTGEN). EcoDemonstrator is a Boeing test program which utilizes advanced experimental equipment to accelerate the science of aerospace and environmentally friendly technologies. The ASTAR Flight Test provided a proof-of-concept flight demonstration that exercised an algorithmic-based application in an actual aircraft. The test aircraft conducted Interval Management operations to provide time-based spacing off a target aircraft in non-simulator wind conditions. Work was conducted as a joint effort between NASA and Boeing to integrate ASTAR in a Boeing supplied B787 test aircraft while using a T-38 aircraft as the target. This demonstration was also used to identify operational risks to future flight trials for the NASA Air Traffic Management Technology Demonstration expected in 2017.
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Two full scale crash tests were conducted on a small MD-500 helicopter at NASA Langley Research Center fs Landing and Impact Research Facility. One of the objectives of this test series was to compare airframe impact response and occupant injury data between a test which outfitted the airframe with an external composite passive energy absorbing honeycomb and a test which had no energy absorbing features. In both tests, the nominal impact velocity conditions were 7.92 m/sec (26 ft/sec) vertical and 12.2 m/sec (40 ft/sec) horizontal, and the test article weighed approximately 1315 kg (2900 lbs). Airframe instrumentation included accelerometers and strain gages. Four Anthropomorphic Test Devices were also onboard; three of which were standard Hybrid II and III, while the fourth was a specialized torso. The test which contained the energy absorbing honeycomb showed vertical impact acceleration loads of approximately 15 g, low risk for occupant injury probability, and minimal airframe damage. These results were contrasted with the test conducted without the energy absorbing honeycomb. The test results showed airframe accelerations of approximately 40 g in the vertical direction, high risk for injury probability in the occupants, and substantial airframe damage.
The Proton Improvement Plan II (PIP-II) project is an essential upgrade to Fermilab’s particle accelerator complex to enable the world’s most intense neutrino beam for LBNF/DUNE and a broad particle physics program for many decades to come. PIP-II will deliver 1.2 MW of proton beam power from the Main Injector, upgradeable to multi-MW capability. The central element of PIP-II is an 800 MeV superconducting radio frequency (SRF) linac, which comprises a room temperature front end followed by an SRF section. The SRF section consists of five different flavors of cavities/cryomodules, including Half Wave Resonators (HWR), Single Spoke and elliptical resonators operating at, or above, state-of-the-art parameters. The first two PIP-II cryomodules, Half Wave Resonator (HWR) and Single Spoke Resonator 1 (SSR1) were installed in the PIP-II Injector Test facility (PIP2IT) and have accelerated beam to above 17 MeV. PIP-II is the first U.S. accelerator project that will be constructed with significant contributions from international partners, including India, Italy, France, United Kingdom and Poland. The project was baselined in April 2022, and the construction phase is underway.
The Multiphysics Object-Oriented Simulation Environment (MOOSE) Framework, as well as MOOSE-based simulation tools, have accelerated the development of fission energy and advanced reactor technologies through the United States Department of Energy, Office of Nuclear Science, Nuclear Energy Advanced Modeling & Simulation (NEAMS) Program. MOOSE contains a complete platform of multiphysics simulation capabilities, capable of running on massively parallel systems, and is developed in an open-source manner with great attention paid to high-quality software quality assurance practices. This overall approach could greatly benefit the fusion energy community, which requires rapid design iteration and improvement in order to facilitate the successful development of fusion as an alternative energy source to fossil fuels. In the first half of this talk, applications of MOOSE and MOOSE-based tools for advanced reactor designs will be showcased, as well as MOOSE ecosystem infrastructure (such as the NEAMS Virtual Test Bed) that enables and accelerates fission reactor design. In the second half, a discussion of how the MOOSE approach to modeling and simulation is currently being applied internationally in fusion energy research and development at the United Kingdom Atomic Energy Authority will be discussed, and ongoing/future domestic research efforts will be highlighted.
Abstract Using an MHD simulation of near tail reconnection associated with a flow burst and the collapse (dipolarization) of the inner tail in combination with test particle tracing we study the acceleration and flux increases of energetic oxygen ions (O + ). The characteristic orbits, distributions, and acceleration mechanisms are governed by the dimensionless parameter σ = ω ci t n , where ω ci is the ion gyro frequency and t n a characteristic Alfvén time of the MHD simulation. For σ < 1, central plasma sheet (CPS) populations after the passage of the dipolarization front are found to resemble half‐shells in velocity space oriented toward dusk. They originate from within the CPS and are energized typically by a single encounter of the region of enhanced cross‐tail electric field associated with the flow burst. For larger σ values ( σ > 1) the O + distributions resemble more closely those of protons, consisting of two counter‐streaming field‐aligned beams and an, albeit more tenuous and irregular, ring population perpendicular to the magnetic field. The existence of the beams, however, depends on suitable earthward moving source populations in the plasma sheet boundary layer or the adjacent lobes. The acceleration to higher energies is found to indicate a charge dependence, consistent with a dominance of more highly charged ions at energies of a few hundred keV. As in earlier simulations, the simulated fluxes show large anisotropies and nongyrotropic effects, phase bunching, and spatially and temporally localized beams.
The effect of an acceleration field on the burning rate of a solid propellant was measured from -900g's to +1000g's using both double base and ammonium perchlorate based propellants. The acceleration fields were simulated using a centrifuge device and the burning rate was recorded. Both metalized and non-metalized variations of each propellant were tested and it was found that acceleration fields affect the burning rate. For the most part the theoretical predictions and the experimental results agreed.
It is known that the predictive life of the refractory ceramic liner of nuclear waste glass melters is conservative, as demonstrated by performance of these materials such as in the Defense Waste Processing Facility (DWPF). The motivation for this task is to maximize the useful life of the melters that will be operated at the Waste Treatment and Immobilization Plant (WTP), which will in turn minimize procurement and disposal costs and melter outage times, as well as to identify maximum loadings in the waste glass of those species that corrode melter components. This task was initiated jointly with Pacific Northwest National Laboratory (PNNL) with the objective to develop a methodology and model to enable more accurate prediction of refractory service life under prototypic conditions from laboratory-scale material corrosion tests. Refractory corrosion is generally reported as physical material loss, measured in units of distance (e.g., inch) or as physical material loss rate, measured in units of distance per time (e.g., inch/day). In post-operational melters, the refractory corrosion is measured directly, sometimes reported as corrosion depth. Crucible tests are used in the laboratory to accelerate the refractory corrosion to facilitate a meaningful measurement in a commensurate amount of time. Crucible tests are particularly useful in understanding refractory corrosion across a large glass composition space, where operational testing would be prohibitive. Some of the critical parameters that are known to influence refractory corrosion by molten glass in a crucible test are temperature, system redox, molten salt phases, glass chemistry, and test duration. The majority of data collected for Monofrax® K-3 (hereafter referred to as K-3) corrosion is from crucible tests, but a small amount comes directly from scaled and production melters. Crucible test data has been collected under varying conditions, whereas data collected from operational melters is relatively fewer and represents conditions specific to the melter campaign. The result is that the published data can be grouped and analyzed in multiple ways, not all of which are readily comparable. The Standard Test Method for Isothermal Corrosion Resistance of Refractories to Molten Glass (ASTM C621) outlines the general guidelines used across industry. That method describes a sealed, static test in which the surface area of the refractory coupon and the volume of glass are fixed. A significant portion of the crucible data pertaining to nuclear waste glasses has been collected in a modified configuration; the most notable differences being the surface area of the refractory coupon to volume of the glass and use of a method for bubbling the melt. To our knowledge, the influence of those parameters on the refractory corrosion has not been quantified. In this work, it was determined that static tests and bubbled tests would be performed. Savannah River National Laboratory (SRNL) was tasked with setting up and performing static testing while PNNL was tasked with setting up and performing bubbled testing. Initial activities were performed to establish laboratory methods that reproduce data comparable to existing data sets of K-3 refractory corrosion by low activity waste (LAW) and high-level waste (HLW) glass compositions. Later activities were focused on refining the test parameters to establish a standard test practice to be used between Laboratories and collecting additional data to be used in the enhanced waste glass model development. This document serves primarily to convey the refractory loss measurement results from corrosion testing of K-3 refractory with waste glass compositions developed for use in the WTP melters. The data will be used in the enhanced property/composition models being developed for waste glass vitrification and melter operations.
Compact balanced-bellows dry type spirometer was designed to be insensitive to acceleration fields along any or all coordinate axes. It provides true indication of respiratory action of test subject without need for calibration in acceleration fields.
In support of the Constellation Space Suit Element [CSSE], a new space-suit architecture will be created for support of Launch, Entry, Abort, Microgravity Extra- Vehicular Activity [EVA], and post-landing crew operations, safety and, under emergency conditions, survival. The space suit is unique in comparison to previous launch, entry, and abort [LEA] suit architectures in that it utilizes rigid mobility elements in the scye (i.e., shoulder) and the upper arm regions. The suit architecture also utilizes rigid thigh disconnect elements to create a quick disconnect approximately located above the knee. This feature allows commonality of the lower portion of the suit (from the thigh disconnect down), making the lower legs common across two suit configurations. This suit must interface with the Orion vehicle seat subsystem, which includes seat components, lateral supports, and restraints. Due to the unique configuration of spacesuit mobility elements, combined with the need to provide occupant protection during dynamic vehicle events, risks have been identified with potential injury due to the suit characteristics described above. To address the risk concerns, a test series has been developed in coordination with the Injury Biomechanics Research Laboratory [IBRL] to evaluate the likelihood and consequences of these potential issues. Testing includes use of Anthropomorphic Test Devices [ATDs; vernacularly referred to as "crash test dummies"], Post Mortem Human Subjects [PMHS], and representative seat/suit hardware in combination with high linear acceleration events. The ensuing treatment focuses on test purpose and objectives; test hardware, facility, and setup; and preliminary results.
The Space Technology-7 Disturbance Reduction System (DRS) is an experiment package aboard the European Space Agency (ESA) LISA Pathfinder spacecraft. LISA Pathfinder launched from Kourou, French Guiana on December 3, 2015. The DRS is tasked to validate two specific technologies: colloidal micro-Newton thrusters (CMNT) to provide low-noise control capability of the spacecraft, and drag-free controlflight. This validation is performed using highly sensitive drag-free sensors, which are provided by the LISA Technology Package of the European Space Agency. The Disturbance Reduction System is required to maintain the spacecrafts position with respect to a free-floating test mass to better than 10nm/(square root of Hz), along its sensitive axis (axis in optical metrology). It also has a goal of limiting the residual accelerations of any of the two test masses to below 30 x 10(exp -14) (1 + ([f/3 mHz](exp 2))) m/sq s/(square root of Hz), over the frequency range of 1 to 30 mHz.This paper briefly describes the design and the expected on-orbit performance of the control system for the two modes wherein the drag-free performance requirements are verified. The on-orbit performance of these modes are then compared to the requirements, as well as to the expected performance, and discussed.
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The Rotor Systems Research Aircraft (RSRA) is a unique research aircraft designed to flight test advanced helicopter rotor system. Its principal flight test configuration is as a compound helicopter. The fixed wing configuration of the RSRA was primarily considered an energy fly-home mode in the event it became necessary to sever an unstable rotor system in flight. While it had always been planned to flight test the fixed wing configuration, the selection of the RSRA as the flight test bed for the X-wing rotor accelerated this schedule. This paper discusses the build-up to, and the test of, the RSRA fixed wing configuration. It is written primarily from the test pilot's perspective.
The Rotor Systems Research Aircraft (RSRA) is a unique research aircraft designed to flight test advanced helicopter rotor system. Its principal flight test configuration is as a compound helicopter. The fixed wing configuration of the RSRA was primarily considered an energy fly-home mode in the event it became necessary to sever an unstable rotor system in flight. While it had always been planned to flight test the fixed wing configuraion, the selection of the RSRA as the flight test bed for the x-wing rotor accelerated this schedule. This paper discusses the build-up to, and the test of, the RSRA fixed wing configuration. It is written primarily from the test pilot's perspective.
A method has been proposed to utilize the well-known Compton scattering process as a tool to measure the centroid energy of a high energy electron beam at the 0.01% level. It is suggested to use the Compton scattering of an infrared laser off the electron beam, and then to measure the energy of the scattered gamma-rays very precisely using solid-state detectors. The technique proposed is applicable for electron beams with energies from 200 MeV to 16 GeV using presently available lasers. This technique was judged to be the most viable of all those proposed for beam energy measurements at the nearby Continuous Electron Beam Accelerator Facility (CEBAF). Plans for a prototype test of the technique are underway, where the main issues are the possible photon backgrounds associated with an electron accelerator and the electron and laser beam stabilities and diagnostics. The bulk of my ASEE summer research has been spent utilizing the expertise of the staff at the Aerospace Electronics Systems Division at LaRC to assist in the design of the test. Investigations were made regarding window and mirror transmission and radiation damage issues, remote movement of elements in ultra-high vacuum conditions, etc. The prototype test of the proposed laser backscattering method is planned for this December.