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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 145 records · Page 8

Initial Flight Tests of the NASA F-15B Propulsion Flight Test Fixture

Flights of the F-15B/Propulsion Flight Test Fixture (PFTF) with a Cone Drag Experiment (CDE) attached have been accomplished at NASA Dryden Flight Research Center. Mounted underneath the fuselage of an F-15B airplane, the PFTF provides volume for experiment systems and attachment points for propulsion experiments. A unique feature of the PFTF is the incorporation of a six-degree-of-freedom force balance. The force balance mounts between the PFTF and experiment and measures three forces and moments. The CDE has been attached to the force balance for envelope expansion flights. This experiment spatially and inertially simulates a large propulsion test article. This report briefly describes the F-15B airplane, the PFTF, and the force balance. A detailed description of the CDE is provided. Force-balance ground testing and stiffness modifications are described. Flight profiles and selected flight data from the envelope expansion flights are provided and discussed, including force-balance data, the internal PFTF thermal and vibration environment, a handling qualities assessment, and performance capabilities of the F-15B airplane with the PFTF installed.

Palumbo, Nathan↗

Full-Scale Hydrodynamic Evaluation of a Modified Navy J4F-2 Amphibian with a 0.425-Scale XP5M-1 Hull Bottom. TED No. NACA DE325

An investigation was made to evaluate the hydrodynamic qualities of a 0.425-scale model of the Navy XP5M-1 hull, which was installed on a modified Navy J4F-2 amphibian. Longitudinal and directional stability during take-off and landing, low-speed maneuverability, spray characteristics, and take-off performance were investigated. The behavior of the airplane in moderately rough water was also observed. The opinions of three pilots have been correlated with the data.

Land, Norman S.↗

Integrated transient modeling of gas turbine and sCO2 power cycle for exhaust heat recovery application

For distributed generation installations, the transient response of the power generation system is critical to meet power quality (voltage and frequency) requirements. Transient models for gas turbine and supercritical carbon dioxide (sCO2) power cycle were integrated for an exhaust heat recovery bottoming cycle system for a distributed generation application. The transient model for the SGT-750 Siemens gas turbine was a ‘black-box’ functional mockup interface (FMI) model developed by Siemens Industrial Turbomachinery in $Finsp\mathring{a}ng$, Sweden. The SGT-750 is a twin-shaft gas turbine that produces 40 MW electricity with an efficiency of about 40% at ISO conditions. At 100% gas turbine throttle (load), the SGT-750 has average exhaust conditions of 114.6 kg/s and 469.8 °C.

20 FOSSIL-FUELED POWER PLANTS↗

Spatial Transferability of Machine Learning Based Volume Estimation Models

High-quality traffic volume data is essential for efficient transportation planning and operations. However, such high-quality data is expensive to collect, owing primarily to the high capital cost of installing and maintaining continuous counting stations (CCSs). Recent availability of probe-based vehicle data offers a cost-effective solution for increasing the observability of traffic volumes. However, having ample ground truth traffic data is a prerequisite for developing robust volume estimation models. Though this might not be a big issue in many states, states with scarce CCS data might be able to benefit from robust volume estimation models developed in (adjacent) data-rich states. While there is a reasonable amount of spatial transferability research in the transportation domain, there is a dearth of knowledge on the spatial transferability of probe-based volume estimation models. To address this gap, this paper explores spatial transferability of volume estimation models developed from data in three states (Colorado, North Carolina, and Pennsylvania). Results indicate that it is extremely important to maintain temporal consistency when attempting spatial transferability of volume estimation models. It was also found that models trained on regions with lower peak traffic volumes will limit the performance of models transferred to states with higher peak hourly traffic volumes. Corroborating findings from existing spatial transferability research on other topics, it was found that a meta-model (developed using data from multiple states) performs better than volume estimation models developed within any one of the states.

ADVANCED PROPULSION SYSTEMS↗

Improvements in Reflected Target Non-intrusive Assessment (ReTNA)

Accurate optical surfaces are a primary driver of concentrated solar power plant performance. Errors in pointing and tracking mirrors, the canting of individual mirror facets, and the surface slope of the mirror itself can be caused by errors during assembly, transportation, wind loading, gravity, and many other sources. The tools that exist to measure these error sources today largely rely on fringe deflectometry (SOFAST, QDec, others), or photogrammetry with targets attached to the mirror surface. In 2022, NREL presented a new indoor optical measurement system to measure fully assembled heliostats during development and on the assembly line for quality assurance purposes, which has undergone significant development in the last year, including the installation of a new, larger laboratory setup. This system, called ReTNA (Reflected Target Non-intrusive Assessment), uses a printed pattern as a deflectometry target. Using printed pattern features as deflectometry targets instead of fringes allows the software to measure the surface slope in two dimensions, eliminating the need to for changing, projected targets. In the last year, NREL's ReTNA tool has been adapted to use a tall, thin target, that only spans one dimension of the mirror, and a camera moving on an automatic track system. We will present these new developments, including the new setup, target patterns, software methodology for fast, automatic optical analysis, and important lessons learned throughout the process. ReTNA results will be compared to established tools, to establish the uncertainty of this new method. ReTNA leverages recent improvements in computer vision and photogrammetry to remove as much careful calibration from the setup process as possible, making the tool low cost, simple, and portable. While it will not achieve the resolution of a fringe deflectometry system, its advantages make it well suited for CSP evaluation, and allow it to fill a different industry need.

concentrating solar power↗

Figures of Merit Software: Description, User's Guide, Installation Notes, Versions Description, and License Agreement

Figures of Merit (FoMs) and the FoM software provide a method for quantitatively evaluating the quality of a regolith simulant by comparing the simulant to a reference material. FoMs may be used for comparing a simulant to actual regolith material, specification by stating the value a simulant s FoMs must attain to be suitable for a given application and comparing simulants from different vendors or production runs. FoMs may even be used to compare different simulants to each other. A single FoM is conceptually an algorithm that computes a single number for quantifying the similarity or difference of a single characteristic of a simulant material and a reference material and provides a clear measure of how well a simulant and reference material match or compare. FoMs have been constructed to lie between zero and 1, with zero indicating a poor or no match and 1 indicating a perfect match. FoMs are defined for modal composition, particle size distribution, particle shape distribution, (aspect ratio and angularity), and density. This TM covers the mathematics, use, installation, and licensing for the existing FoM code in detail.

hoelzer, H. D.↗

FAST-1.2 User Installation and Verification Guide: Developed Under NQA-1-2017

The purpose of this document is to provide the user information about the installation of Fuel Analysis for Steady state and Transient (FAST)-1.2 on their computers or servers. General information about the code and supported operating systems is described in Section 1.0. Self-service oriented FAST-1.2 software licensing steps are described in Section 2.0. An installation verification test suite is provided with FAST-1.2 and described in Section 3.0. A convenience script for converting Fuel Rod Analysis Program – Constant (FRAPCON) to FAST inputs is discussed in Section 4.0. FAST-1.2 was developed and released under a software quality assurance program based upon NQA-1-2017 at Pacific Northwest National Laboratory (PNNL). FAST-1.2 is the latest baseline code. The installation verification test suite contains both steady state and transient Anticipated Operation Occurrences (AOOs), accident conditions, such as Reactivity Initiated Accidents (RIAs) and Loss of Coolant Accidents (LOCAs).

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗

Pilot Study for Multifamily Building Ventilation and Indoor Air Quality

Weatherization Program Notice (WPN) 17-7 issued by the US Department of Energy (DOE) Weatherization Assistance Program (WAP) requires that buildings have ventilation in accordance with ASHRAE Standard 62.2-2016 (entitled Ventilation and Indoor Air Quality in Residential Buildings) in dwelling units weatherized under the program. The 2016 version of the standard expanded its scope of application to include all multifamily dwelling units. This has resulted in concerns for buildings where installing ventilation in individual units is costly or otherwise logistically difficult. Also, excessive ventilation rates could significantly increase energy costs, and may cause indoor air quality issues within the buildings. One deficiency that is noted is that the standard does not provide a credit for existing infiltration in multifamily buildings that reduces the required mechanical ventilation levels. This report details findings from a field study investigating envelope air-tightness, inter-unit connectivity, and indoor air quality in centrally ventilated high-rise multifamily buildings with central ventilation systems serving individual units in the state of New York. As allowed under WPN 17-7, the State of New York has a variance in the application of ASHRAE Standard 62.2-2016 in select types of multifamily buildings to provide time to determine how best to implement the standard. The purpose of this pilot study is to characterize the impact that weatherization and feasible ventilation improvements have on the indoor air quality of large, multifamily buildings with centrally ventilated apartments, as currently performed under WAP in the State of New York under their variance request (i.e., to implement ASHRAE Standard 62.2-2016 “to the greatest extent possible” in this type of multifamily building). A major goal is to determine if these practices improve or at least “do no harm” to the indoor air quality of the weatherized multifamily buildings and to the occupants themselves.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗

Statistical Behavior of Low-Amplitude Power System Point-on-Wave Measurements

The power grid is undergoing massive changes to ensure resiliency and reliability in a more decentralized world. Distributed energy resources are becoming a prominent source of generation, potentially leading to a lack of centralized generation sources. Due to these new behaviors and system topologies, it is important to install measurement devices that are 1) accurate and 2) self-aware of their measurement quality. In this paper, a residential-scale microgrid is used to generate voltage and current waveforms, captured by Verivolt and National Instruments measurement equipment. A least-squares approach is used to separate the “clean” signals from the noise. Finally, Gaussian mixture modeling is used to approximate noise distributions, and it is shown these higher-order distribution estimates are a better fit to voltage and current noise profiles than single-mode Gaussian estimates.

24 POWER TRANSMISSION AND DISTRIBUTION↗

High temperature strain gage technology for gas turbine engines

This report summarizes the results of a six month study that addressed specific issues to transfer the Pd-13Cr static strain sensor to a gas turbine engine environment. The application issues that were addressed include: (1) evaluation of a miniature, variable potentiometer for use as the ballast resistor, in conjunction with a conventional strain gage signal conditioning unit; (2) evaluation of a metal sheathed, platinum conductor leadwire assembly for use with the three-wire sensor; and (3) subjecting the sensor to dynamic strain cyclic testing to determine fatigue characteristics. Results indicate a useful static strain gage system at all temperature levels up to 1350 F. The fatigue characteristics also appear to be very promising, indicating a potential use in dynamic strain measurement applications. The procedure, set-up, and data for all tests are presented in this report. This report also discusses the specific strain gage installation technique for the Pd-13Cr gage because of its potential impact on the quality of the output data.

Fichtel, Edward J.↗

Sensitivity Study of the Wall Interference Correction System (WICS) for Rectangular Tunnels

An off-line version of the Wall Interference Correction System (WICS) has been implemented for the NASA Langley National Transonic Facility. The correction capability is currently restricted to corrections for solid wall interference in the model pitch plane for Mach numbers less than 0.45 due to a limitation in tunnel calibration data. A study to assess output sensitivity to measurement uncertainty was conducted to determine standard operational procedures and guidelines to ensure data quality during the testing process. Changes to the current facility setup and design recommendations for installing the WICS code into a new facility are reported.

Walker, Eric L.↗

High Voltage Solar Concentrator Experiment with Implications for Future Space Missions

This paper describes the design, development, fabrication, and test of a high performance, high voltage solar concentrator array. This assembly is believed to be the first ever terrestrial triple-junction-cell solar array rated at over 1 kW. The concentrator provides over 200 W/square meter power output at a nominal 600 Vdc while operating under terrestrial sunlight. Space-quality materials and fabrication techniques were used for the array, and the 3005 meter elevation installation below the Tropic of Cancer allowed testing as close as possible to space deployment without an actual launch. The array includes two concentrator modules, each with a 3 square meter aperture area. Each concentrator module uses a linear Fresnel lens to focus sunlight onto a photovoltaic receiver that uses 240 series-connected triple-junction solar cells. Operation of the two receivers in series can provide 1200 Vdc which would be adequate for the 'direct drive' of some ion engines or microwave transmitters in space. Lens aperture width is 84 cm and the cell active width is 3.2 cm, corresponding to a geometric concentration ratio of 26X. The evaluation includes the concentrator modules, the solar cells, and the materials and techniques used to attach the solar cells to the receiver heat sink. For terrestrial applications, a finned aluminum extrusion was used for the heat sink for the solar cells, maintaining a low cell temperature so that solar cell efficiency remains high.

Mehdi, Ishaque S.↗

Payload Processing for Mice Drawer System

Experimental payloads flown to the International Space Station provide us with valuable research conducted in a microgravity environment not attainable on earth. The Mice Drawer System is an experiment designed by Thales Alenia Space Italia to study the effects of microgravity on mice. It is designed to fly to orbit on the Space Shuttle Utilization Logistics Flight 2 in October 2008, remain onboard the International Space Station for approximately 100 days and then return to earth on a following Shuttle flight. The experiment apparatus will be housed inside a Double Payload Carrier. An engineering model of the Double Payload Carrier was sent to Kennedy Space Center for a fit check inside both Shuttles, and the rack that it will be installed in aboard the International Space Station. The Double Payload Carrier showed a good fit quality inside each vehicle, and Thales Alenia Space Italia will now construct the actual flight model and continue to prepare the Mice Drawer System experiment for launch.

Brown, Judy↗

Acoustic Measurements of a Large Civil Transport Main Landing Gear Model

Microphone phased array acoustic measurements of a 26 percent-scale, Boeing 777-200 main landing gear model with and without noise reduction fairings installed were obtained in the anechoic configuration of the Virginia Tech Stability Tunnel. Data were acquired at Mach numbers of 0.12, 0.15, and 0.17 with the latter speed used as the nominal test condition. The fully and partially dressed gear with the truck angle set at 13 degrees toe-up landing configuration were the two most extensively tested configurations, serving as the baselines for comparison purposes. Acoustic measurements were also acquired for the same two baseline configurations with the truck angle set at 0 degrees. In addition, a previously tested noise reducing, toboggan-shaped fairing was re-evaluated extensively to address some of the lingering questions regarding the extent of acoustic benefit achievable with this device. The integrated spectra generated from the acoustic source maps reconfirm, in general terms, the previously reported noise reduction performance of the toboggan fairing as installed on an isolated gear. With the recent improvements to the Virginia Tech tunnel acoustic quality and microphone array capabilities, the present measurements provide an additional, higher quality database to the acoustic information available for this gear model.

Ravetta, Patricio A.↗

Electro-optical flight deflection measurement system

This paper describes an electrooptical flight-deflection measurement system (FDMS) developed for use on highly-maneuverable-aircraft-technology (HiMAT) RPV flight research program. The FDMS provides in-flight measurements of the aircraft structural deflections and magnetic-tape recordings for automated data processing. The capabilities and limitations, requirements for installation on an aircraft, analytical considerations, and typical flight data acquired from the HiMAT research program are examined. The flight data indicate that the background light is the major obstacle to acquiring high-quality data and that the relationship between the target displacement and the output of the FDMS is nonlinear; however, the nonlinear effects can be minimized with judicious planning of the installation of the FDMS on the aircraft. Excellent flight deflection data were obtained from both the HiMAT and X-29 A flight research program with very little data lost as a result of encounters with severe background light.

Deangelis, V. Michael↗

Status of the MQXFB Nb 3 Sn Quadrupoles for the HL-LHC

Here, the cold powering test of the first two prototypes of the MQXFB quadrupoles (MQXFBP1, now disassembled, and MQXFBP2), the Nb 3 Sn inner triplet magnets to be installed in the HL-LHC, has validated many features of the design, such as field quality and quench protection, but has found performance limitations. In fact, both magnets showed a similar phenomenology, characterized by reproducible quenches in the straight part inner layer pole turn, with absence of training and limiting the performance at 93% (MQXFBP1) and 98% (MQXFBP2) of the nominal current at 1.9 K, required for HL-LHC operation at 7 TeV. Microstructural inspections of the quenching section of the limiting coil in MQXFBP1 have identified fractured Nb 3 Sn sub-elements in strands located at one specific position of the inner layer pole turn, allowing to determine the precise origin of the performance limitation. In this paper we outline the strategy that has been defined to address the possible sources of performance limitation, namely coil manufacturing, magnet assembly and integration in the cold mass.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

Strategies for mitigating residual magnetic field effect on pre-production PIP-II SSR2 cryomodule performance

This paper outlines the strategy aimed at mitigating the adverse effects of residual magnetic fields on the performance of pre-production SSR2 superconducting cavities within the context of the PIP-II project at Fermilab. Residual magnetic fields can significantly impact cavity performance, leading to reduced quality factor. To address this challenge, our strategy integrates various approaches including magnetic shielding, careful selection of materials, quality controls aimed at measuring magnetic permeability, magnetic hygiene to reduce residual magnetic field at the installation phase. Additionally, experimental studies are being planned to analyze the behavior of the cavities under different magnetic field conditions, and the effectiveness of advanced demagnetization procedures.

43 PARTICLE ACCELERATORS↗

Use of the LANDSAT-2 data collection system in the Colorado River basin weather modification program

The author has identified the following significant results. Many types of environmental sensors can be interfaced to the LANDSAT DCP. The LANDSAT field installations proved to be remarkably reliable, weather resistant, and cost effective units able to relay high quality data in near real time. The wind averaging system demonstrated the feasibility of transmitting averaged wind data, stored over a period of several hours, from a remote site.

Kahan, A. M.↗