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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 91 records · Page 5
All sourcesNASA NTRSDOE OSTI
DOE OSTI2020

Characterization of the Benefit of APS Flash Coatings in Improving TBC Lifetime

The addition of an air plasma sprayed (APS) “flash” layer on top of a high velocity oxygen fuel (HVOF) bond coating has been shown to extend the lifetime of thermal barrier coatings. A series of furnace cycle tests (FCTs) has been conducted at 1100 °C in air + 10% H 2 O to study the benefit of flash coatings on rod and disk alloy 247 specimens and provide a better mechanistic understanding of their benefit. Flash coatings of NiCoCrAlY and NiCoCrAlYHfSi both improved the FCT lifetime of rod specimens tested in 100-h cycles and disk specimens tested in 1-h cycles. In 1-h cycles, the NiCoCrAlY flash coating significantly outperformed an HVOF-only NiCoCrAlYHfSi bond coating and a NiCoCrAlYHfSi flash coating. Both flash coatings increased the bond coating roughness compared to HVOF. During exposure, the flash layer formed an intermixed alumina-metal layer that appeared to inhibit crack formation. Using a time series of observations, the lower Y + Hf content in the Y-only flash coating appeared to reduce Al consumption. The HVOF layer acted as a source of Al for the adjacent mixed zone. A second series of specimens included a fully APS bond coating where oxide had penetrated through the entire coating to the substrate after only 100, 1-h cycles and lifetime was similar to an HVOF-only bond coating. The inner HVOF layer with the outer APS flash coating prevented this complete penetration from occurring.

Pint, Bruce↗
DOE OSTI2018

KLF2 attenuates bleomycin-induced pulmonary fibrosis and inflammation with regulation of AP-1

Highlights: • KLF2 is downregulated in BLM-treated rats. • KLF2 alleviates BLM-induced lung fibrosis. • KLF2 suppresses the production of pro-inflammatory cytokines. • KLF2 prevents TGF-β1 induced lung fibrosis in vitro. • Effects of KLF2 on AP-1. Pulmonary fibrosis (PF) is a chronic, fibrosing interstitial pneumonia and devastating disease. Here we investigated the potential roles of Kruppel-like factor 2 (KLF2) on pulmonary fibrosis and inflammation response. A mouse model of pulmonary fibrosis was established by intratracheal injection of bleomycin (BLM). The mRNA and protein levels of KLF2 were assayed by RT-PCR and Western blotting respectively. The extent of lung fibrosis was determined using hematoxylin and eosin (HE) staining and Masson's trichrome staining, and the hydroxyproline content was quantified. RT-PCR was used to evaluate the mRNA expression of collagen type 1a1 (col1a1), col3a1, α-SMA, TNF-α, IL-1β and IL-6. The concentrations of TNF-α, IL-1β, and IL-6 in bronchoalveolar lavage fluid (BALF) and lung tissue were examined by ELISA. Also, the effects of KLF2 on activator protein-1 (AP-1) were evaluated by measuring the c-Jun and c-Fos protein levels. We found that KLF2 was remarkably downregulated in BLM-treated rats, both in mRNA and protein levels. Additionally, overexpression of KLF2 attenuated the destruction of the alveolar space and pulmonary interstitial collagen hyperplasia, and deposition reduced the expression of col1a1, col3a1, and α-SMA, and blocked the production of TNF-α, IL-1β, and IL-6 in BALF and lung tissue in vivo. Moreover, adenoviral transduction of KLF2 inhibited TGF-β1-induced expression of col1a1, col3a1, and α-SMA in vitro. Mechanically, BLM up-regulated c-Jun and c-Fos expression, which was impeded by KLF2 overexpression. Taken together, our data indicate that KLF2 attenuates pulmonary fibrosis and inflammation, possibly through the regulation of AP-1.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2015

An experimental study on sub-cooled flow boiling CHF of R134a at low pressure condition with atmospheric pressure (AP) plasma assisted surface modification

In this study, sub-cooled flow boiling critical heat flux tests at low pressure were conducted in a rectangular flow channel with one uniformly heated surface, using simulant fluid R-134a as coolant. The experiments were conducted under the following conditions: (1) inlet pressure (P) of 400-800 kPa, (2) mass flux (G) of 124-248 kg/m 2 s, (3) inlet sub-cooling enthalpy (ΔH i ) of 12~ 26 kJ/kg. Parametric trends of macroscopic system parameters (G, P, H i ) were examined by changing inlet conditions. Those trends were found to be generally consistent with previous understandings of CHF behavior at low pressure condition (i.e. reduced pressure less than 0.2). A fluid-to-fluid scaling model was utilized to convert the test data obtained with the simulant fluid (R-134a) into the prototypical fluid (water). The comparison between the converted CHF of equivalent water and CHF look-up table with same operation conditions were conducted, which showed good agreement. Furthermore, the effect of surface wettability on CHF was also investigated by applying atmospheric pressure plasma (AP-Plasma) treatment to modify the surface characteristic. With AP-Plasma treatment, the change of microscopic surface characteristic was measured in terms of static contact angle. The static contact angle was reduced from 80° on original non-treated surface to 15° on treated surface. An enhancement of 18% on CHF values under flow boiling conditions were observed on AP-Plasma treated surfaces compared to those on non-treated heating surfaces.

42 ENGINEERING↗
DOE OSTI2014

Celastrol ameliorates HIV-1 Tat-induced inflammatory responses via NF-kappaB and AP-1 inhibition and heme oxygenase-1 induction in astrocytes

HIV-1 Tat causes extensive neuroinflammation that may progress to AIDS-related encephalitis and dementia. Celastrol possesses various biological activities such as anti-oxidant, anti-tumor, and anti-inflammatory activities. In this study, we investigated the modulatory effects of celastrol on HIV-1 Tat-induced inflammatory responses and the molecular mechanisms underlying its action in astrocytes. Pre-treatment of CRT-MG human astroglioma cells with celastrol significantly inhibited HIV-1 Tat-induced expression of ICAM-1/VCAM-1 and subsequent monocyte adhesiveness in CRT-MG cells. In addition, celastrol suppressed HIV-1 Tat-induced expression of pro-inflammatory chemokines, such as CXCL10, IL-8, and MCP-1. Celastrol decreased HIV-1 Tat-induced activation of JNK MAPK, AP-1, and NF-κB. Furthermore, celastrol induced mRNA and protein expression of HO-1 as well as Nrf2 activation. Blockage of HO-1 expression using siRNA reversed the inhibitory effect of celastrol on HIV-1 Tat-induced inflammatory responses. These results suggest that celastrol has regulatory effects on HIV-1 Tat-induced inflammatory responses by blocking the JNK MAPK-AP-1/NF-κB signaling pathways and inducing HO-1 expression in astrocytes. - Highlights: • Celastrol suppressed HIV-1 Tat-induced expression of pro-inflammatory genes. • Celastrol inhibited HIV-1 Tat -induced activation of JNK MAPK. • Celastrol inhibited HIV-1 Tat-induced activation of both NF-κB and AP-1. • Celastrol inhibited HIV-1 Tat-induced inflammatory responses via HO-1 induction.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2024

AP-XPS Study of the Reaction of O 2 and CO 2 with Zn–Au(111) Surface Alloys: Activation of O–O/C–O Bonds and the Formation of ZnO

Synchrotron-based ambient-pressure X-ray photoelectron spectroscopy (AP-XPS) was used to study the dissociation of O 2 and CO 2 on Zn-Au(111) alloys which contained 0.2-0.3 monolayers of zinc. Although Au(111) is inert, the alloys displayed a high activity for the cleavages of O-O and C-O bonds at room temperature with the formation of ZnO x species. Dissociative adsorption of O 2 at 300 K destroyed the alloys and the results of AP-XPS pointed to the co-existence of two types of oxygen species on the surface: ZnO x and chemisorbed O atoms (O chem ) on Au or the Au-ZnO interface. Annealing from room temperature to 600 K induced a O chem → ZnO x transformation that reflected the poor stability of O atoms on Au(111). The Zn-Au(111) systems exhibited a reactivity towards CO 2 that was much larger than that seen for Au(111), Cu(111) or surfaces of late transition metals like, Ni, Pd or Pt. At 300 K, CO 2 underwent partial dissociation depositing large amounts of O chem on the surface with minor formation of ZnO x . In addition, the deposited O chem reacted with CO 2 to form surface carbonate groups. Dosing of CO 2 at 500-600 K mainly led to the formation of ZnO x and the surface carbonate almost disappeared. In the presence of hydrogen, i.e. reaction feeds with a CO 2 to H 2 ratio of 1:3, the surface chemistry at 300 K was very similar to that seen for pure CO 2 with the formation of ZnO x and carbonate groups. In contrast, at 500-600 K, reaction with hydrogen induced the removal of ZnO x and CO 3 /HCOO species. Finally, our AP-XPS results are consistent with the idea that CO 2 hydrogenation on AuZn alloys involves a redox process where there is sequential oxidation by CO 2 and reduction by H 2 to yield methanol.

36 MATERIALS SCIENCE↗
DOE OSTI2019

Media comparison of filtration with Hanford tank AP-107 supernate

The present experimental work was performed in order to investigate media performance in both cross-flow and dead-end filtration on 9 L of Hanford tank AP-107 supernatant. Media grades 0.1 and 5 were tested for each the cross-flow filter (CFF) and dead-end filter (DEF). The CFFs were tested in the cells unit filter (CUF) system in recycle mode and the DEFs (in-line and disc) were used to dewater the feed. Visual inspection of the feed material indicated essentially no settled insoluble solids in the feed material. The 5 micron grade cross flow filter produced stable filter fluxes while the flux for the 0.1 micron grade material steadily decayed. The 5 media grade BDEF (backpulsed dead-end filter) was effective at removing solids from the AP-107 feed and when backpulsed, fully restored the filter flux, indicating that the solids did not irreversibly foul the filter. The 0.1 media grade DEF was used to filter the final 2 liters of AP-107 feed drained from the CUF and collect solids on the filter media. Additional DEF filtering was performed on 4 L of BDEF permeate in order to assess whether small particles that cause fouling in the 0.1 media grade filter passed through the 5 media grade filter. There was no indication of fouling and limited solids were observed on the filter. In conclusion, a direct comparison of filtration rates between the 0.1 and 5 media grade filters for both the CFF and DEF showed the 5 media grade filter flux was, on average, 200 times higher than the 0.1 media grade filter while still effectively filtering the solids.

38 RADIATION CHEMISTRY, RADIOCHEMISTRY, AND NUCLEA↗
DOE OSTI2019

Cesium Ion Exchange Testing Using Crystalline Silicotitanate with Hanford Tank Waste 241-AP-107

Pacific Northwest National Laboratory has been tasked with demonstrating the unit operations for the Low Activity Waste Pretreatment System with actual Hanford tank waste. Crystalline silicotitanate (CST) ion exchange media is planned to be used to remove cesium (137Cs) from the aqueous phases of the tank wastes. Washington River Protection Solutions requested that Hanford tank waste collected from tank 241-AP-107 be processed using conceived pretreatment steps (suspended solids removal by filtration, Cs removal by ion exchange), then vitrified. Removal of Cs from these wastes is an important processing step in preparing the waste for long-term safe storage. Bench-scale ion exchange testing with approximately 9 L of filtered AP-107 supernate was conducted using CST. Column testing was performed using prototypic LAWPS operations in a lead-lag column arrangement using 10-mL CST beds. Feed was processed until the lag column effluent reached the Hanford Tank Waste Treatment and Immobilization Plant waste acceptance criteria (WAC) for receiving supernatant waste for vitrification (a function of the Na and 137Cs concentrations), at which point, a new lag column was needed to continue processing and the original lag column was moved to the lead position. Greater than 99% of the Cs processed through the ion exchange system was collected on the CST in the columns. The AP-107 feed and column processing effluent underwent extensive characterization to better define waste characteristics and assess fractionation to the CST. Selected lead column samples were analyzed to assess particular metal analyte load characteristics. Results of these analyses will be discussed.

cesium exchange, Hanford tank waste, ion exchange↗
DOE OSTI2013

DISCOVERY OF AN EXTENDED X-RAY JET IN AP LIBRAE

Chandra observations of the low-energy-peaked BL Lac object (LBL) AP Librae (AP Lib) revealed the clear discovery of a non-thermal X-ray jet. AP Lib is the first LBL with an extended non-thermal X-ray jet that shows emission into the very high energy range. The X-ray jet has an extension of ∼15''(≈ 14 kpc). The X-ray jet morphology is similar to the radio jet observed with Very Large Array at 1.36 GHz emerging in the southeast direction and bends by 50° at a distance of 12'' toward the northeast. The intensity profiles of the X-ray emission studied are consistent with those found in the radio range. The spectral analysis reveals that the X-ray spectra of the core and jet region are both inverse-Compton-(IC)-dominated. This adds to a still small sample of BL Lac objects whose X-ray jets are IC-dominated and thus more similar to the high-luminosity Fanaroff-Riley II sources than to the low-luminosity Fanaroff-Riley I objects, which are usually considered to be the parent population of BL Lac objects.

79 ASTRONOMY AND ASTROPHYSICS↗
DOE OSTI2018

Crossflow Filtration of Hanford Tank AP-105 Supernatant

A small-scale test platform to demonstrate the solids filtration, Cs removal, and low-activity waste (LAW) vitrification was constructed and installed at the Pacific Northwest National Laboratory (PNNL) 325 Building. Bench scale testing was conducted to demonstrate cross flow filtration using the cells unit filter (CUF) on approximately 14 liters of 241-AP-105 feed to support the confirmation of the Low-Activity Waste Pretreatment System (LAWPS) equipment performance and design basis for entrained solids removal process. Despite the low solids content (~16 ppm) of the AP-105 feed, significant fouling of the filter was observed that required backpulsing of the filter to maintain the permeate flux within the LAWPS baseline design rate. The improvement from backpulsing was significant, but transitory, and lasted a few hours. Increasing the transmembrane pressure was shown to have limited impact on the permeate flux in terms of magnitude and duration, especially compared with backpulsing. Because LAWPS must operate three to eight days to throughput requirements, testing demonstrated that backpulsing or chemical cleaning may need to be done every 7 to 14 hours when processing feed from AP-105. Because of this, backpulsing capability is strongly recommended for the baseline design. The LAWPS prototypic filter cleaning was demonstrated at the end of testing and was shown to be very effective as it largely restored the filter permeability to near pre-test conditions.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2019

AP-105 Melter Offgas Condensate and EMF Evaporator Concentrate Raman and LIBS Qualitative Evaluation for the use of In-Line Monitoring (Rev. 0)

The Pacific Northwest National Laboratory (PNNL) was tasked to perform Raman spectroscopy and laser induced breakdown spectroscopy (LIBS) testing on the melter off-gas condensate generated during low-activity waste process testing of a sample from Hanford Site tank AP-105 and/or evaporate from evaporation of the condensate. This was a proof-of-principle demonstration that Raman spectroscopy and LIBS have the potential to be used as analytical tools for in-line process analysis of key aqueous phase analytes in radioactive process streams associated with the Hanford Waste Treatment and Immobilization Plant. The work completed under this project complements work completed for WRPS with the development of in-line monitoring systems to characterize and quantify constituents of tank waste following Cs removal and filtration. The WRPS work is currently limited to Raman sensors and utilizes chemometric models for quantification of several anionic species in the sample system. It should be noted that while this approach can be applied to off-gas condensate streams, new chemometric models are needed to accurately quantify analytes under off-gas condensate conditions. The work completed under this project makes timely use of available samples and equipment at PNNL. The project utilized the opportunity to collect off-gas samples from planned AP-105 processing work and included the direct condensate and the evaporate from the DFLAW Radioactive Waste Test Platform. Samples were characterized by instruments already in place at PNNL including a Raman spectrometer optimized for in-line monitoring of flowing and stationary samples as well as a LIBS instrument, which was optimized for static liquid droplet analysis. The ultimate objective was to determine if these techniques could be used to qualitatively characterize analytes present within the off-gas samples. The testing confirmed the use of the Raman as an in-line monitoring system was able to qualitatively observe NO 3 - , NO 2 - , aluminum (as aluminate, Al(OH) 4 - ), SO 4 2- , CrO 4 2- , CO 3 2- , and PO 4 3- in the AP-105 melter feed evaporator condensate samples. The testing also confirmed LIBS as a potential useful technique for in-line monitoring, able to qualitatively detect Na, N, Al, and tentatively Cr and Cl in a simulant stock evaporate solution.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2021

Intercomparison of Aerosol Instrumental Responses Using AEROTRAK, SMPS, and APS in a Simulated Building

In this work, three aerosol instruments were intercompared by using data collected from field campaigns in a simulated building environment during the last quarter of 2020 from October to December at Oak Ridge National Laboratory. The three aerosol instruments—AeroTrak Model 9110, Scanning Mobility Particle Spectrometer (SMPS) 3080L + 3025A, and Aerodynamic Particle Sizer (APS) 3320—were manufactured by TSI Inc. to perform in situ measurements of particle number concentration in the air. These instruments were co-located in one room in which an aerosol generator was used to produce a defined aerosol population for the instruments to sample and detect in each campaign. The SMPS measured aerosol particles with diameters from 0.01 to 0.7 µm, APS measured aerosol particles with diameters from 0.5 to 20 µm, and AeroTrak measured aerosol particles with diameters from 0.1 to 10 µm. The results suggest that although AeroTrak is fast and easy to use, it does not provide measurements comparable with those obtained by SMPS and APS. The differences in particle counts were orders of magnitude in size (i.e., the AeroTrak data were unreasonably small in the tested scenarios). The results clearly indicate that AeroTrak should not be used in ambient applications in which the level of particle concentration is expected to be high. This would cause difficulty to a campaign in which the dilution factor is unknow a priori. The high particle concentration could also lead to an erroneous aerosol size distribution (e.g., a bimodal size distribution was measured as opposed to a single-mode one). The number concentration limit that AeroTrak is expected to run reliably (i.e., with a counting coincidence error less than ±10%) is approximately three to four per cubic centimeter. This suggests that the instrument is best used in a clean room environment, not in an ambient or indoor application, such as the Flexible Research Platform campaigns.

47 OTHER INSTRUMENTATION↗
DOE OSTI2021

Fiscal Year 2021 Filtration of Hanford Tank 241-AP-107 Supernatant Samples Obtained at Prototypic Tank Level and Filtered at 16 °C

Bench-scale filtration testing of 8.5 liters of supernatant from Hanford waste tank 241-AP-107, chilled to 16 °C, was conducted using a backpulse dead-end filter (BDEF) filtration system equipped with a feed vessel and a Mott inline filter Model 6610 (Media Grade 5) in the hot cells of the Radiochemical Processing Laboratory at Pacific Northwest National Laboratory. This was done to assess the impact of a lower sampling location within the tank as well the lowered filtration temperature on supernatant stability and fouling. The as-received samples were transferred to 1.5-liter poly bottles and held at 16 °C for approximately 1 week prior to filtration. The feed was filtered through the BDEF system at a targeted flux of 0.065 gpm/ft 2 to match the prototypic operation of the TSCR system. During the initial period of filtration, the differential pressure required to effect filtration at 0.065 gpm/ft 2 increased until it reached 2 psid [the Tank Side Cesium Removal (TSCR) action limit] at 26 hours. After this, the filter was backpulsed to dislodge accumulated solids and reduce this pressure differential. An additional eight backpulses were conducted during the initial filtration period; each time, the target pressure was reached sooner than during the previous interval. Volume filtered decreased from 0.9 to 0.03 m 3 /m 2 over the course of 14 processing hours. After the ninth backpulse, the backpulse frequency had become unsustainable, and it was decided to perform an extensive filter cleaning. The filter was cleaned by draining the chilled AP-107 feed into chilled holding containers, introducing 0.1 M NaOH into the feed vessel, and recirculating the NaOH through the system for 20 minutes before allowing the system to soak for 2 hours without temperature control. A measurable decrease in filter resistance during this recirculation indicated that the 0.1 M NaOH was likely dissolving some of the solids that had deposited on the filter. Post cleaning, the filter resistance was effectively restored to initial conditions as the initial transmembrane pressure was restored to original levels. However, resumed processing of the AP-107 feed at 16 °C continued to result in an increased rate of filter resistance. An additional five backpulses were conducted (four during feed processing, one during subsequent cleaning) before the conclusion of the test. Solids concentrated from the backpulse solutions displayed sodium oxalate-type phases, Al-oxides and sodium Al-oxides/carbonates, iron oxides, and Ca-bearing phases (calcite). The scanning electron microscopy analyses also revealed a large distribution of particles, with some particles, notably sodium phosphate dodecahydrate, having diameters close to 0.5 mm.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2022

Fiscal Year 2022. Filtration of Hanford Tank 241-AP-101 Supernatant at 16 °C

Bench-scale filtration testing of ~9 liters of supernatant from Hanford waste tank 241-AP-101, chilled to 16 °C, was conducted using a backpulse dead-end filter (BDEF) filtration system equipped with a feed vessel and a Mott inline filter Model 6610 (Media Grade 5) in the hot cells of the Radiochemical Processing Laboratory at Pacific Northwest National Laboratory. This was done to assess the performance of the anticipated third feed to the Tank Side Cesium Removal (TSCR) system. The as-received samples were diluted to the target sodium concentration and transferred to 1.5-liter polyethylene bottles and held at 16 °C for approximately 1 week prior to filtration. The feed was filtered through the BDEF system at a targeted flux of 0.065 gpm/ft 2 to match the prototypic operation of the TSCR system. During filtration, the differential pressure required to effect filtration at 0.065 gpm/ft 2 increased little over the filtration campaign and never reached 2 psid (the TSCR action limit). This indicates that the TSCR filter should perform well when processing AP-101 supernatant. After completing filtration of the AP-101 feed, the filter was cleaned. Solids concentrated from the backpulse solutions displayed sodium nitrate-type phases, aluminum and silicon phases reported as cancrinite or nitrate-cancrinite, a mixed chromium-aluminum oxide, iron oxides, and Ca-bearing phases (calcite). Scanning electron microscopy analyses showed that the average particle size was 0.5 micron.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2019

SGP Merged Aerosol Size Distribution (CPC+SMPS+APS)

Five years (2009-2013) of data from three instrument at the SGP site were merged in order to create a new aerosol size distribution dataset. Data from the scanning mobility particle sizer (SMPS), part of the TDMA system, were combined with size distribution data from the aerodynamic particle sizer (APS). The merged size distribution from those two instruments spanned the diameter (mobility) size range between ~12 nm and ~14 um with 215 bins (Collins 2010). Total aerosol number concentrations from a TSI 3010 condensation particle counter (CPC) were then used to adjust and constrain the SMPS+APS size distributions and to extend the size distribution down to ~7 nm. Collins, D: Tandem Differential Mobility Analyzer/Aerodynamic Particular Sizer (APS) Handbook. DOE ARM Climate Research Facility. DOE/SC-ARM-TR-090, 2010.

54 ENVIRONMENTAL SCIENCES↗
NASA NTRS1976

Properties of Ap stars in the ultraviolet

A review is presented of the current state of knowledge concerning the emitted flux distributions of Ap stars and their ultraviolet photometric variability especially as it relates to photometric and spectrum variability observed in the visible. A table of Ap stars observed in the ultraviolet from space vehicles is presented along with a graph which shows the observed flux distributions, normalized to unity flux at 3320 A, for the Si star theta Aur and for the normal stars 134 Tau and gamma UMa. Attention is given to ultraviolet color indices and ultraviolet light curves for variable Ap stars.

Leckrone, D. S.↗
NASA NTRS1982

A study of X-ray emission from Ap and Am stars

Twenty stars classified as either Ap or Am have been imaged by the Imaging Proportional Counter on the Einstein Observatory in a search for evidence of coronal emission. It is found that an Am star will not be a source (at the 10 to the 28th ergs/sec level) unless it is in a spectroscopic binary with a period below about 10 days. The X-rays in the close binaries can be explained by the RS CVn effect in the late-type secondary, and the evidence is against strong emission from Am stars. Among the nine Ap stars observed, four were detected. While it is possible that the X-rays are being generated by undetected late-type dwarf companions, the large fraction of detections makes the Ap stars themselves the likely source of emission.

Cash, W.↗
NASA NTRS2005

Reverse Kinematic Analysis and Uncertainty Analysis of the Space Shuttle AFT Propulsion System (APS) POD Lifting Fixture

The space shuttle Aft Propulsion System (APS) pod requires precision alignment to be installed onto the orbiter deck. The Ground Support Equipment (GSE) used to perform this task cannot be manipulated along a single Cartesian axis without causing motion along the other Cartesian axes. As a result, manipulations required to achieve a desired motion are not intuitive. My study calculated the joint angles required to align the APS pod, using reverse kinematic analysis techniques. Knowledge of these joint angles will allow the ground support team to align the APS pod more safely and efficiently. An uncertainty analysis was also performed to estimate the accuracy associated with this approach and to determine whether any inexpensive modifications can be made to further improve accuracy.

Brink, Jeffrey S.↗
DOE OSTI2017

BPM STABILTIY STUDIES FOR THE APS MBA UPGRADE

The Advanced Photon Source (APS) is currently in the preliminary design phase for the multi-bend achromat (MBA) lattice upgrade. Beam stability is critical for the MBA and will require long term drift defined as beam mo-tion over a seven-day timescale to be no more than 1 mi-cron at the insertion device locations and beam angle change no more than 0.25 micro-radian. Mechanical stabil-ity of beam position monitor (BPM) pickup electrodes mounted on insertion device vacuum chambers place a fun-damental limitation on long-term beam stability for inser-tion device beamlines. We present the design and imple-mentation of prototype mechanical motion system (MMS) instrumentation for quantifying this type of motion specif-ically in the APS accelerator tunnel and experiment hall floor under normal operating conditions. The MMS pres-ently provides critical position information on the vacuum chamber and BPM support systems. Initial results of the R&D prototype systems have demonstrated that the cham-ber movements far exceed the long-term drift tolerance specified for the APS Upgrade MBA storage ring.

Lill, R.↗