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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 775 records · Page 43

Overview of Plume-Surface Interaction Data from Subscale Inert Gas Testing at NASA MSFC Test Stand 300 Vacuum Facilities

Maturation and validation of predictive modeling capabilities for plume-surface interactions and their effects requires relevant, highly characterized ground test data. The National Aeronautics and Space Administration has developed a test bed for these behaviors under its Game Changing Developments Plume Surface Interactions project, and has undertaken testing at the Marshall Space Flight Center to address critical data needs. This manuscript provides a high-level overview of the testing and its associated data.

Chad J Eberhart↗

Extended Wear Testing of the 12-kW Advanced Electric Propulsion System Engineering Test Unit Hall Thruster

This work presents a summary of the first wear test of the 12 kW Advanced Electric Propulsion System (AEPS) intended to isolate the impact of discharge current on component wear rates. Testing was led by Aerojet Rocketdyne and performed with the AEPS Engineering Test Unit 2 (ETU-2) thruster. In total, approximately 860 hours of operation were accumulated split between operating conditions of 600 V/9 kW, 600 V/11 kW, and 600 V/12 kW. Thruster performance and stability were invariant throughout the wear test for all thruster throttle conditions and shown to be equal to the values previously measured with ETU-2. Inner front pole cover erosion rates were found to be invariant to discharge current as the measurements at all three operating conditions were equal to within the empirical uncertainty. Outer front pole cover erosion rates were found to be equal for the 600 V/9 kW and 600 V/12 kW conditions with operation at 600 V/11 kW yielding elevated erosion rates. Overall, the data shows that the AEPS thruster design has a high probability of meeting lifetime and performance requirements as the design proceeds to flight production and qualification.

Jason D Frieman↗

Extended Wear Testing of the 12-kW Advanced Electric Propulsion System Engineering Test Unit Hall Thruster

This work presents a summary of the first wear test of the 12 kW Advanced Electric Propulsion System (AEPS) intended to isolate the impact of discharge current on component wear rates. Testing was led by Aerojet Rocketdyne and performed with the AEPS Engineering Test Unit 2 (ETU-2) thruster. In total, approximately 860 hours of operation were accumulated split between operating conditions of 600 V/9 kW, 600 V/11 kW, and 600 V/12 kW. Thruster performance and stability were invariant throughout the wear test for all thruster throttle conditions and shown to be equal to the values previously measured with ETU-2. Inner front pole cover erosion rates were found to be invariant to discharge current as the measurements at all three operating conditions were equal to within the empirical uncertainty. Outer front pole cover erosion rates were found to be equal for the 600 V/9 kW and 600 V/12 kW conditions with operation at 600 V/11 kW yielding rates that were comparable to those on the inner front pole cover. Overall, the data shows that the AEPS thruster design has a high probability of meeting lifetime and performance requirements as the design proceeds to flight production and qualification.

HERMeS↗

Ruggedness Evaluation of ASTM International Standard Test Methods for Shape Memory Materials: E3097 Standard Test Method for Mechanical Uniaxial Constant Force Thermal Cycling of Shape Memory Alloys

This paper evaluates the ruggedness testing of the newly released ASTM International E3097 Standard Test Method for Mechanical Uniaxial Constant Force Thermal Cycling of Shape Memory Alloys. The ruggedness experiment was designed with eight runs in two replicates, consisting of seven factors of strain rate (ė), heating and cooling rates (Ṫ(heat) and Ṫ(cool), respectively), upper and lower cycle temperatures (UCT and LCT, respectively), hold time (thold), and minimum load (Fmin) imparted on the samples. The results indicate that the hold time factor had no effect on any result variable. The minimum load factor, alternatively, had the greatest effect on several result variables, with the greatest influence on the strains at martensite start and finish (strain variation ~0.1 percent), and the strains at the upper and lower cycle temperatures (strain variation of 0.14 percent). The UCT was found to have a large effect on the austenite and martensite finish tangent line and data intersect, denoted by Af* and Mf*, by ~17 and 4 °C, respectively. The testing methodology, analysis techniques, and resulting conclusions on the ruggedness of the test methods are presented.

shape memory alloy↗

Mechanical Testing of Soils from the South Range of the Utah Test and Training Range: Derivation of Soil Properties to Support the Earth Entry System Landing for Mars Sample Return

This report summarizes results from laboratory tests conducted by Applied Research Associates, Inc. (ARA) on soil samples collected from multiple sites within the South Range of the U.S. Air Force Utah Test and Training Range (UTTR). The goal of the laboratory tests was to establish soil constitutive properties and develop computational soil models enabling NASA to simulate impact landings of the Earth Entry System (EES) for the Mars Sample Return (MSR) mission. Test methods and results are presented describing the strength, compressibility, and stiffness of soils in the UTTR South Range including methods to incorporate the measured properties into Ansys LS-DYNAÒ constitutive material models for EES landing simulations.

Soil↗

NASA’s Space Launch System: Comprehensive Test Program Leads to Mission Success during Artemis I Flight Test

NASA’s SLS (Space Launch System) rocket had a successful first launch on Nov. 16, 2022, sending an uncrewed Orion spacecraft to the Moon on the agency’s Artemis I mission. Ten 6U CubeSats were also deployed from SLS during the mission. Orbital insertion parameters, including insertion velocity and altitude, were within hundredths and tenths of a percent from predicted values, corroborating data collected from the individual elements that showed similar performance accuracy. While launch remains the main test – and Artemis I was a true test flight – to collect data, confirm and refine computer models, and validate hardware test data, multiple test programs led up to the first flight and enabled the historic launch. Additionally, SLS was designed from the beginning to be a crew-rated launch vehicle, and teams put the astronauts who will fly on it at the forefront of the development process. This paper and presentation will cover the SLS design and development programs that led to the successful Artemis I mission, and which have set the stage to send the first astronauts back to cislunar space since the Apollo 17 crew in 1972.

John Honeycutt↗

Development of Electrical Capacitance Sensors for Accident Tolerant Fuel (ATF) Testing at the Transient Reactor Test (TREAT) Facility

A variety of instruments are being developed and qualified to support the Accident Tolerant Fuels (ATF) program and future transient irradiations at the Transient Reactor Test (TREAT) facility at Idaho National Laboratory (INL). The University of New Mexico (UNM) is working with INL to develop capacitance-based void sensors for determining the timing of critical boiling phenomena in static capsule fuel testing and the volume-averaged void fraction in flow-boiling in-pile water loop fuel testing. The static capsule sensor developed at INL is a plate-type configuration, while UNM is utilizing a ring-type capacitance sensor. Each sensor design has been theoretically and experimentally investigated at INL and UNM. Experiments are being performed at INL in an autoclave to investigate the performance of these sensors under representative Pressurized Water Reactor (PWR) conditions in a static capsule. Experiments have been performed at UNM using air-water two-phase flow to determine the sensitivity and time response of the capacitance sensor under a flow boiling configuration. Initial measurements from the capacitance sensor have demonstrated the validity of the concept to enable real-time measurement of void fraction. The next steps include designing the cabling interface with the flow loop at UNM for Reactivity Initiated Accident (RIA) ATF testing at TREAT and further characterization of the measurement response for each sensor under varying conditions by experiments and modeling.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗

FEASIBILITY ASSESSMENT FOR DEVELOPING AN INTEGRAL LOCA TESTING CAPABILITY AT THE TRANSIENT RESEARCH TEST (TREAT) REACTOR

The study of Light Water Reactor (LWR) fuel performance in Loss of Coolant Accidents (LOCAs) has been a significant and evolving field since the beginning of the commercialization of LWR technology. The following paper presents the results of feasibility assessment to develop an in-pile, integral LOCA testing capability using the recently restarted TREAT reactor located at the Idaho National Laboratory (INL). Critical performance objectives for the testing platform are derived from a review of known LWR fuel degradation phenomena in LOCA scenarios. Advanced modeling and simulation tools were then used to gain additional insight into both the system performance and fuel performance characteristics of LOCA testing at TREAT. Results show that TREAT is well suited to conduct in-pile integral LOCA testing.

42 ENGINEERING↗

Release of a High Temperature Engineering Test Reactor (HTTR) Steady-State Multiphysics Model to the Virtual Test Bed

The National Reactor Innovation Center (NRIC) accelerates the demonstration and deployment of advanced nuclear energy through inspiring stakeholders and the public, empowering innovators, and delivering successful outcomes. The Virtual Test Bed (VTB) supports this mission by providing an open-source repository of advanced test reactor models for industry, academia, and the public to utilize. During my time at Idaho National Laboratory (INL), I: • Verified the input files of the High Temperature Engineering Test Reactor • Generated computational results • Created user documentation for the HTTR • Uploaded a steady-state HTTR model to the Virtual Test Bed • Authored a conference publication on the model

22 GENERAL STUDIES OF NUCLEAR REACTORS↗

Qualifying the Instrument Thimble 11 Test Position in the Advanced Test Reactor Critical

The Advanced Test Reactor (ATR) is a versatile nuclear research reactor located at the Idaho National Laboratory (INL) in Eastern Idaho, United States of America. It is one of the most powerful and flexible research reactors in the world and is primarily used for materials testing, isotope production and basic nuclear science research. The ATR is a light-water-cooled, beryllium-moderated reactor with a nominal thermal power capacity of 250 MW utilizing specially designed fuel, arranged in a serpentine pattern to create 9 flux traps. The special design of ATR allows for the neutron flux within each of the flux traps providing flexibility for experiments, programs and allowing experiments with different dose requirements to be irradiated simultaneously. The Advance Test Reactor Critical (ATRC) is a full-scale replica of the ATR core but is housed in a pool instead of a pressure vessel. ATRC is usually operated at less than 600 watts [1]. There are 12 dry instrument thimbles located around the outside of the core tank where a variety of measurement equipment is housed to facilitate reactor operations. Currently Instrument Thimble 11 (IT-11) is not utilized in ATR or ATRC. A range of measurements is ongoing to qualify IT-11 as a test platform for nuclear instrumentation research, development and further experimentation.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗

Cold Test Results of Pre-Production PIP-II SSR2 Cavities with High-Power Couplers in the Fermilab Spoke Test Cryostat

As part of the PIP-II project at Fermilab, a pre-production cryomodule featuring 325 MHz Single Spoke Resonator type 2 (SSR2) superconducting RF cavities is under construction. These SSR2 cavities are fabricated by industry partners and undergo initial cold testing at our collaborating institution, IJCLab in France, utilizing low-power coupler. Subsequently, the cavities are subjected to final qualification at Fermilab, complete with tuner and high-power coupler assemblies. This paper provides an overview of the ongoing efforts dedicated to high-power testing of jacketed SSR2 cavities in the Spoke Test Cryostat (STC) at Fermilab. Performance parameters obtained from these tests are presented, offering valuable insights into the cavities operational characteristics and readiness for integration into the PIP-II cryomodule.

43 PARTICLE ACCELERATORS↗

Performance comparison of charcoal cookstoves for Haiti: Laboratory testing with Water Boiling and Controlled Cooking Tests

Charcoal cooking accounts for a large portion of Haiti's energy usage and leads to severe economic, health, and environmental hardships. Organizations are hoping that fuel-efficient cookstoves can help solve the problem. In this study, four charcoal cookstoves intended for dissemination in Haiti were rigorously assessed and compared using Water Boiling and Controlled Cooking Tests. Due to the poor thermal efficiency of the traditional stove, all improved stoves saved fuel on average over the traditional with the majority also reducing the total emissions released. However, the traditional stove could be difficult to replace because it had the fastest time-to-boil, an important consideration for end users. Here, through the testing, the number of trials conducted was found to be an important consideration for error analysis. Also, noticeable differences in stove performance were seen between the two protocols, supporting arguments by prior researchers of the necessity to use multiple test protocols for practically useful comparisons.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗

Test Report #33: Compressor Calorimeter Test of R-410A Alternative: R-32/R-134a Mixture Using a Scroll Compressor

This report investigates the tested performance of lower - GWP candidate refrigerant, 94.07 wt% R - 32 + 5.93 wt % R - 134 a mixture (hereafter referred to as R - 32/134a), as an alternative to baseline refrigerant R - 410 A using a 36,000 Btu/hr compressor calorimeter located at the Heat Exchanger Advanced Testing Facility at Oak Ridge National Laboratory . These tests were conducted during May and August 2013. R - 410A is a near - azeotropic blend of R - 32 and R - 125 with 0.5/0.5 mass fraction and has a GWP 100 of 2100. R - 32 and R - 134a are pure refrigerants and have GWP 100 of 716 and 1370 1, respectively. Based on the GWP 100 values of pure refrigerants and their mass fraction in the blend, GWP 100 of R - 32/134a, which is under development by National Refrigerant, is 755. This report compares various performance parameters, such as cooling capacity, compressor power, refrigerant mass flow rate, EER, isentropic efficiency and discharge temperature of the alternative refrigerant to that of R - 410 A.

42 ENGINEERING↗

Ground Vibration Testing at NASA Armstrong, Emphasizing on Passive Aeroelastic Tailored Wing Ground Vibration Test Using Fixed Base Correction Method

How does experimental mechanics contribute to aircraft aeroelastic airworthiness? The aviation community is always improving analysis and testing techniques to realize quicker, cheaper, reliable solutions. A ground vibration test (GVT) is conducted to identify structural mode shapes, frequencies, and damping values to validate analytical models used for flutter analysis, which shows whether a structure has acceptable aeroelastic flutter margins for airworthiness. The FLL recently conducted a GVT of the Passive Aeroelastic Tailored (PAT) Wing using an experimental modal technique called Fixed Base Correction (FBC). The GVT objective was to obtain the PAT wing modal characteristics to compare test results with finite element model (FEM) results for the tow-steered wingbox.

loads testing↗

High Temperature Test Facility At Scale Testing, Validation, and Demonstration

Theses slides will be used to brief the Tribal DOE and Council Chairman for the project listed below. The High Temperature Test Facility (HTTF) is a demonstration-scale high temperature electrolysis (HTE) system that provides the ability to produce, process, store, and dispense electrolytically produced hydrogen. The system will be designed to accommodate electrolysis systems from various industry partners. The HTTF will be supplied up to 10 MW of power for electrolysis at 5 separate test article locations, each up to 2MW. The system will include post-processing and compression, storage, and capabilities to provide hydrogen for consumption by future end users. The HTTF will also provide the ability to test and demonstrate an HTE system in a configuration that would simulate the use of a nuclear generated steam supply for the high temperature heat source. The HTTF will be located at the Central Facilities Area (CFA) adjacent to CFA-686 on the INL site, 45 miles west of Idaho Falls.

08 HYDROGEN↗