MSC Apollo 13 Investigation Team. Panel 8 - High Pressure Oxygen Systems Survey
Analysis of procedures for determining fire or explosion hazards of materials exposed to liquid or gaseous oxygen
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Analysis of procedures for determining fire or explosion hazards of materials exposed to liquid or gaseous oxygen
The degradation of photovoltaic (PV) balance of systems (BoS) components is not well-studied, but the consequences include offline modules, strings, and inverters; system shutdown; arc faults; and fires. A utility provider experienced a ~30% failure rate in their power transfer chain, originally attributed to branch connectors. Field-failed specimen assemblies were therefore examined, consisting of cable connector, branch connector, and discrete fuse components. In this study, unused field-vintage specimens are examined using combined-accelerated stress testing (C-AST) to clarify the most influential environmental stressors as well as the effect of external mechanical perturbation. A benchtop prototype fixture was used to develop the perturbation capability for the C-AST chamber. The benchtop experiments were also used to develop the in-situ data acquisition of specimen current, voltage, and temperature. A significant increase in operating temperature (~100 degrees C from ~40 degrees C) and a different failure mode were observed promptly once periodic mechanical perturbation was applied. The current at failure was decreased from 35 A (with failure in the fuses) to 15 A (failure at the male/female metal pin connection). After initial examination using X-ray computed tomography, the external plastic was machined away from failed specimens to allow for failure analysis, including the extraction of the internal convolute springs for morphological examination (optical and electron microscopy).
The degradation of photovoltaic (PV) balance of systems (BoS) components is not well studied, but the consequences include offline modules, strings, and inverters; system shutdown; arc faults; and fires. A utility provider experienced a ~30% failure rate in their power transfer chain, originally attributed to branch connectors. Field-failed specimen assemblies were, therefore, examined, consisting of cable connector, branch connector, and discrete fuse components. In this study, unused field-vintage specimens are examined using a benchtop prototype fixture to identify the most influential environmental stressors on BoS components as well as the effect of external mechanical perturbation. The prototype fixture was used to develop a perturbation capability for future use in the combined-accelerated stress testing chamber. The benchtop experiments were also used to develop the in-situ data acquisition of specimen current, voltage, and temperature. A significant increase in operating temperature (~100 °C from ~40 °C) and a different failure mode (arcing at the metal pins rather than overheating of the fuse filament) were observed promptly once periodic mechanical perturbation was applied. The current at failure was decreased from 35 A (measured for static specimens, with failure occurring in the fuses) to 15 A (for tests with mechanical perturbation, with failure at the male/female metal pin connection). After initial examination using X-ray computed tomography, the external plastic was machined away from failed specimens to allow for failure analysis, including the extraction of the internal convolute springs for morphological examination (optical and electron microscopy). Chemical composition analysis included energy-dispersive X-ray spectroscopy, differential scanning calorimetry, and Fourier transform infrared spectroscopy.
Although little can be done to reduce the risks of firefighting, something can be done to curb the injuries and fatalities. This is the goal of Project FIRES, a program jointly sponsored by NASA and the Federal Emergency Management Agency's U.S. Fire Administration with technical management provided by Marshall Space Flight Center. Project FIRES (Firefighter's Integrated Response Equipment System) involves applications of advanced materials and design concepts, derived from Apollo to update existing gear which does not adequately protect against many of the hazards encountered in fire suppression activities. A major focus of the effort involves application to the FIRES ensemble of lightweight, fire-resistant, heat-protective materials originally developed for use in astronauts' space suits or in spacecraft components which require thermal protection. Data from the fourteen municipal fire departments participating in the field evaluation will form a basis for development of new nationwide protective ensemble students.
Creating an economic demand for carbon utilization products will require lowering the overall cost of the products to compete within the current market. Photosynthetic uptake of carbon dioxide is an emerging pathway for product development in the animal feed market that globally amounts to over 400 Billion USD and is expected to continue growing. This project aims to continue the development of a process that utilizes carbon dioxide while increasing the cost competitiveness of algae as an animal feed product. The overall goal of the project is to demonstrate an engineering-scale open raceway pond algae cultivation system (180 m2) including integration of technologies that utilize coal-fired power plant CO2 and wastewater nutrient inputs. The system is designed to maximize the cost-effectiveness and environmental benefits of algal biomass production for commodity animal feed.
The fuel cell energy systems are designed with and without a utility connection for emergency back-up power. Sale of electricity to the utility during periods of low plant demand is not considered. For each of the three industrial applications, conceptual designs were also developed for conventional utility systems relying on purchased electric power and fossil-fired boilers for steam/hot water. The capital investment for each energy system is estimated. Annual operating costs are also determined for each system. These cost estimates are converted to levelized annual costs by applying appropriate economic factors. The breakeven electricity price that would make fuel cell systems competitive with the conventional systems is plotted as a function of naphtha price. The sensitivity of the breakeven point to capital investment and coal price is also evaluated.
This viewgraph presentation concerns the experience that Dryden has had with Certificate of Authorization (COA) in reference to unmanned aerial systems (UAS). It reviews recent Certificate of Authorization UAS's i.e., 2005 Altair NOAA Mission, 2006 Altair Western States Fire Mission, and 2007 Ikhana. The priorities for the safety process is reviewed, as are typical UAS hazards. Slides also review the common COA provisions, best practices and lessons learned, the 2005 NOAA/NASA Science Demonstration Flights and the use of the UAS systems during fire emergencies.
Wildfires in many western North American forests are becoming more frequent, larger, and severe, with changed seasonal patterns. In response, coniferous forest ecosystems will transition toward dominance by fire-adapted hardwoods, shrubs, meadows, and grasslands, which may benefit some faunal communities, but not others. We describe factors that limit and promote faunal resilience to shifting wildfire regimes for terrestrial and aquatic ecosystems. We highlight the potential value of interspersed nonforest patches to terrestrial wildlife. Similarly, we review watershed thresholds and factors that control the resilience of aquatic ecosystems to wildfire, mediated by thermal changes and chemical, debris, and sediment loadings. We present a 2-dimensional life history framework to describe temporal and spatial life history traits that species use to resist wildfire effects or to recover after wildfire disturbance at a metapopulation scale. The role of fire refuge is explored for metapopulations of species. In aquatic systems, recovery of assemblages postfire may be faster for smaller fires where unburned tributary basins or instream structures provide refuge from debris and sediment flows. We envision that more-frequent, lower-severity fires will favor opportunistic species and that less-frequent high-severity fires will favor better competitors. Along the spatial dimension, we hypothesize that fire regimes that are predictable and generate burned patches in close proximity to refuge will favor species that move to refuges and later recolonize, whereas fire regimes that tend to generate less-severely burned patches may favor species that shelter in place. Looking beyond the trees to forest fauna, we consider mitigation options to enhance resilience and buy time for species facing a no-analog future.
Aerosols emitted from wildfires could significantly affect global climate through perturbing global radiation balance. In this study, the Community Earth System Model with prescribed daily fire aerosol emissions is used to investigate fire aerosols’ impacts on global climate with emphasis on the role of climate feedbacks. The total global fire aerosol radiative effect (RE) is estimated to be -0.78 ± 0.29 W m -2 , which is mostly from shortwave RE due to aerosol–cloud interactions (REaci; -0.70 ± 0.20 W m -2 ). The associated global annual-mean surface air temperature (SAT) change ΔT is -0.64 ± 0.16 K with the largest reduction in the Arctic regions where the shortwave REaci is strong. Associated with the cooling, the Arctic sea ice is increased, which acts to reamplify the Arctic cooling through a positive ice-albedo feedback. The fast response (irrelevant to ΔT) tends to decrease surface latent heat flux into atmosphere in the tropics to balance strong atmospheric fire black carbon absorption, which reduces the precipitation in the tropical land regions (southern Africa and South America). The climate feedback processes (associated with ΔT) lead to a significant surface latent heat flux reduction over global ocean areas, which could explain most (~80%) of the global precipitation reduction. The precipitation significantly decreases in deep tropical regions (5°N) but increases in the Southern Hemisphere tropical ocean, which is associated with the southward shift of the intertropical convergence zone and the weakening of Southern Hemisphere Hadley cell. Such changes could partly compensate the interhemispheric temperature asymmetry induced by boreal forest fire aerosol indirect effects, through intensifying the cross-equator atmospheric heat transport.
NorthStar Clean Energy Company (NorthStar) conducted the Filer City Biomass Carbon Removal and Storage (BiCRS) Net-Negative Study to develop a conceptual design and cost estimate for retrofitting the TES Filer City Station with post-combustion carbon capture technology in Mainstee Michigan. The Filer City BiCRS Net-Negative Study allowed NorthStar and team to confirm the commercial feasibility of a post-combustion carbon capture system applied to biomass-fired boilers. At the time of the study, there were no operating facilities in the world with carbon capture applied to flue gas from woody biomass as proposed for Filer City. Due to the solvent-agnostic nature of B&W’s SolveBright™ technology, the team determined that multiple amines, both traditional and proprietary, would be capable of 95% CO 2 capture efficiency with the steam available from Filer City’s existing boilers after modifications to burn 100% biomass. Based on the cost estimates produced, NorthStar can now confirm the Filer City BiCRS Project is economically viable with a combination of tax credits available from the Inflation Reduction Act of 2022 and high-quality Carbon Dioxide Removal Credits sold on the Voluntary Carbon Market. The Filer City BiCRS project is uniquely positioned to become one of the first projects to capture and sequester large volumes of CO 2 from a biogenic source, removing existing CO 2 from the atmosphere. The unlimited version of the Filer City Biomass Carbon Removal and Storage (BiCRS) Net-Negative Study Final Technical Report is attached.
Fire prevention, protection, and fighting systems at KSC for space shuttle operations
A review is presented of the technology involved in integrating the Space Shuttle system. A powered flight analysis of the Shuttle is presented, touching upon the following areas: ascent profile and abort mode integration, sizing and design, control of load factor by a stage thrust shaping, structural load constraints, flight performance reserve and trajectory design for the orbital flight test. A discussion is presented of aerothermodynamics including aerodynamic and plume heating. Flight control and separation is considered with attention paid to liftoff, ascent to booster staging, elevon load relief, booster tailoff thrust mismatch and gimbal limitations and booster separation. Structural analysis and dynamics is examined, considering: vehicle loads and modes and the pogo effect. Propulsion aspects (hydraulics, the LH2 recirculation system, the antigeyser system, the pressurization system, etc.), ground vibration tests, separation system verification and flight readiness firing are all described.
Free graphite fibers released into the environment from resin matrix composite components, as a result of fire and/or explosion, pose a potential hazard to electrical equipment. An approach to prevent the fibers from becoming airborne is to use hybrid composite materials which retain the fibers at the burn site. Test results are presented for three hybrid composites that were exposed to a simulation of an aircraft fire and explosion. The hybrid systems consisted of 16 plies of graphite-epoxy with two plies of Kevlar-, S-glass-, or boron-epoxy on each face. Two different test environments were used. In one environment, specimens were heated by convection only, and then impacted by a falling mass. In the other environment, specimens were heated by convection and by radiation, but were not impacted. The convective heat flux was about 100-120 kW/m in both environments and the radiative flux was about 110 kW/sq m.
An update is presented for the following projects: (1) asphalt pavement recycling; (2) data collection platform/water quality monitoring; (3) digital emergency traffic routing; (4) fire department communications and dispatch system; (5) health department management information system; (6) hazardous materials; (7) coal gasification; and (8) emergency vehicle proximity sensing.
Automatic locating systems which respond to cloud to ground lightning and which discriminate against cloud discharges and background noise are described. Subsystems of the locating system, which include the direction finder and the position analyzer, are discussed. The direction finder senses the electromagnetic fields radiated by lightning on two orthogonal magnetic loop antennas and on a flat plate electric antenna. The position analyzer is a preprogrammed microcomputer system which automatically computes, maps, and records lightning locations in real time using data inputs from the direction finder. The use of the locating systems for wildfire management and fire weather forecasting is discussed.
A radio frequency paging communication system that has coded vibrotactile outputs suitable for use by deaf-blind people was developed. In concept, the system consists of a base station transmitting and receiving unit and many on-body transmitting and receiving units. The completed system has seven operating modes: fire alarm; time signal; repeated single character Morse code; manual Morse code; emergency aid request; operational status test; and message acknowledge. The on-body units can be addressed in three ways: all units; a group of units; or an individual unit. All the functions developed were integrated into a single package that can be worn on the user's wrist. The control portion of the on-body unit is implemented by a microcomputer. The microcomputer is packaged in a custom-designed hybrid circuit to reduce its physical size.
Following the discovery of intense vehicle glow of the Space Shuttle on the STS-3 mission, a new experiment to probe this phenomenon was developed and flown on the Shuttle STS-4 mission. A conventional camera was equipped with an objective transmission grating and several photographic exposures were taken of the Shuttle tail from the aft flight deck window. Vehicle glow surrounding Shuttle surfaces exposed to the ram direction was observed on a long (400 second) exposure. From analysis of the resulting spectral data it appears that the Shuttle glow has a diffuse spectral component in the region 6300 to 8000A. In addition, it has been possible to assess the spectral character of light emitted by the firing of a reaction control system thruster. Our data show that the light emitted from the thruster gases is confined to wavelengths shorter than 7200A.
The Orbiter Primary Reaction Control System (PRCS) pulse width and firing frequency is restricted to prevent excessive loads in the Space Station Freedom (SSF). The feasibility of using the SSF Control Moment Gyros (CMG) as a secondary controller for load relief is evaluated. The studies revealed the CMG not only reduced loads but were useful for other SSF functions: vibration suppression and modal excitation. Vibration suppression lowers the g level for the SSF micro-g experiments and damps the low frequency oscillations that cause crew sickness. Modal excitation could be used for the modal identification experiment and health monitoring. The CMG's reduced the peak loads and damped the vibrations. They were found to be an effective multi-purpose ancillary device for SSF operation.