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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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NASA NTRS1985

Ten year environmental test of glass fiber/epoxy pressure vessels

By the beginning of the 1970's composite pressure vessels had received a significant amount of development effort, and applications were beginning to be investigated. One of the first applications grew out of NASA Johnson Space Center efforts to develop a superior emergency breathing system for firemen. While the new breathing system provided improved wearer comfort and an improved mask and regulator, the primary feature was low weight which was achieved by using a glass fiber reinforced aluminum pressure vessel. Part of the development effort was to evaluate the long term performance of the pressure vessel and as a consequence, some 30 bottles for a test program were procured. These bottles were then provided to NASA Lewis Research Center where they were maintained in an outdoor environment in a pressurized condition for a period of up to 10 yr. During this period, bottles were periodically subjected to cyclic and burst testing. There was no protective coating applied to the fiberglass/epoxy composite, and significant loss in strength did occur as a result of the environment. Similar bottles stored indoors showed little, if any, degradation. This report contains a description of the pressure vessels, a discussion of the test program, data for each bottle, and appropriate plots, comparisons, and conclusions.

Faddoul, J. R.↗
NASA NTRS2007

The Art of Extracting One-Dimensional Flow Properties from Multi-Dimensional Data Sets

The engineering design and analysis of air-breathing propulsion systems relies heavily on zero- or one-dimensional properties (e:g: thrust, total pressure recovery, mixing and combustion efficiency, etc.) for figures of merit. The extraction of these parameters from experimental data sets and/or multi-dimensional computational data sets is therefore an important aspect of the design process. A variety of methods exist for extracting performance measures from multi-dimensional data sets. Some of the information contained in the multi-dimensional flow is inevitably lost when any one-dimensionalization technique is applied. Hence, the unique assumptions associated with a given approach may result in one-dimensional properties that are significantly different than those extracted using alternative approaches. The purpose of this effort is to examine some of the more popular methods used for the extraction of performance measures from multi-dimensional data sets, reveal the strengths and weaknesses of each approach, and highlight various numerical issues that result when mapping data from a multi-dimensional space to a space of one dimension.

Baurle, R. A.↗
NASA NTRS1996

Fundamental relations between short-term RR interval and arterial pressure oscillations in humans

BACKGROUND: One of the principal explanations for respiratory sinus arrhythmia is that it reflects arterial baroreflex buffering of respiration-induced arterial pressure fluctuations. If this explanation is correct, then elimination of RR interval fluctuations should increase respiratory arterial pressure fluctuations. METHODS AND RESULTS: We measured RR interval and arterial pressure fluctuations during normal sinus rhythm and fixed-rate atrial pacing at 17.2+/-1.8 (SEM) beats per minute greater than the sinus rate in 16 healthy men and 4 healthy women, 20 to 34 years of age. Measurements were made during controlled-frequency breathing (15 breaths per minute or 0.25 Hz) with subjects in the supine and 40 degree head-up tilt positions. We characterized RR interval and arterial pressure variabilities in low-frequency (0.05 to 0.15 Hz) and respiratory-frequency (0.20 to 0.30 Hz) ranges with fast Fourier transform power spectra and used cross-spectral analysis to determine the phase relation between the two signals. As expected, cardiac pacing eliminated beat-to-beat RR interval variability. Against expectations, however, cardiac pacing in the supine position significantly reduced arterial pressure oscillations in the respiratory frequency (systolic, 6.8+/-1.8 to 2.9 +/-0.6 mm Hg2/Hz, P=.017). In contrast, cardiac pacing in the 40 degree tilt position increased arterial pressure variability (systolic, 8.0+/-1.8 to 10.8 +/-2.6, P=.027). Cross-spectral analysis showed that 40 degree tilt shifted the phase relation between systolic pressure and RR interval at the respiratory frequency from positive to negative (9 +/-7 degrees versus -17+/-11 degrees, P=.04); that is, in the supine position, RR interval changes appeared to lead arterial pressure changes, and in the upright position, RR interval changes appeared to follow arterial pressure changes. CONCLUSIONS: These results demonstrate that respiratory sinus arrhythmia can actually contribute to respiratory arterial pressure fluctuations. Therefore, respiratory sinus arrhythmia does not represent simple baroreflex buffering of arterial pressure.

NASA Discipline Cardiopulmonary↗
NASA NTRS1998

Interactions between CO2 chemoreflexes and arterial baroreflexes

We studied interactions between CO2 chemoreflexes and arterial baroreflexes in 10 supine healthy young men and women. We measured vagal carotid baroreceptor-cardiac reflexes and steady-state fast Fourier transform R-R interval and photoplethysmographic arterial pressure power spectra at three arterial pressure levels (nitroprusside, saline, and phenylephrine infusions) and three end-tidal CO2 levels (3, 4, and 5%, fixed-frequency, large-tidal-volume breathing, CO2 plus O2). Our study supports three principal conclusions. First, although low levels of CO2 chemoreceptor stimulation reduce R-R intervals and R-R interval variability, statistical modeling suggests that this effect is indirect rather than direct and is mediated by reductions of arterial pressure. Second, reductions of R-R intervals during hypocapnia reflect simple shifting of vagally mediated carotid baroreflex responses on the R-R interval axis rather than changes of baroreflex gain, range, or operational point. Third, the influence of CO2 chemoreceptor stimulation on arterial pressure (and, derivatively, on R-R intervals and R-R interval variability) depends critically on baseline arterial pressure levels: chemoreceptor effects are smaller when pressure is low and larger when arterial pressure is high.

NASA Discipline Cardiopulmonary↗
NASA NTRS2007

Risk Assessment of Physiological Effects of Atmospheric Composition and Pressure in Constellation Vehicles

To limit the risk of fire and reduce denitrogenation time to prevent decompression sickness to support frequent extravehicular activities on the Moon, a hypobaric (PB = 414 mmHg) and mildly hypoxic (ppO2 = 132 mmHg, 32% O2 - 68% N2) living environment is considered for the Crew Exploration Vehicle (CEV) and Lunar Surface Access Module (LSAM). With acute change in ppO2 from 145-178 mmHg at standard vehicular operating pressure to less than 125 mmHg at desired lunar surface vehicular operating pressures, there is the possibility that some crewmembers may develop symptoms of Acute Mountain Sickness (AMS). The signs and symptoms of AMS (headache plus nausea, dizziness, fatigue, or sleeplessness), could impact crew health and performance on lunar surface missions. An exhaustive literature review on the topic of the physiological effects of reduced ppO2 and absolute pressure as may contribute to the development of altitude symptoms or AMS was performed. The results of the nine most rigorous studies were collated, analyzed and contents on AMS and hypoxia symptoms summarized. There is evidence for an absolute pressure effect per se on AMS, so the higher the altitude for a given hypoxic alveolar O2 partial pressure (PAO2), the greater the AMS response. About 25% of adults are likely to experience mild AMS near 2,000 m altitude following a rapid ascent from sea level while breathing air (6,500 feet, acute PAO2 = 75 mmHg). The operational experience with the Shuttle staged denitrogenation protocol at 528 mmHg (3,048 m) while breathing 26.5% O2 (acute PAO2 = 85 mmHg) in astronauts adapting to microgravity suggests a similar likely experience in the proposed CEV environment. We believe the risk of mild AMS is greater given a PAO2 of 77 mmHg at 4,876 m altitude while breathing 32% O2 than at 1,828 m altitude while breathing 21% O2. Only susceptible astronauts would develop mild and transient AMS with prolonged exposure to 414 mmHg (4,876 m) while breathing 32% O2 (acute PAO2 = 77 mmHg). So the following may be employed for operational risk reduction: 1) develop procedures to increase PB as needed in the CEV, and use a gradual or staged reduction in cabin pressure during lunar outbound; 2) train crews for symptoms of hypoxia, to allow early recognition and consider pre-adaptation of crews to a hypoxic environment prior to launch, 3) consider prophylactic acetazolamide for acute pressure changes and be prepared to treat any AMS associated symptoms early with both carbonic anhydrase inhibitors and supplemental oxygen.

Scheuring, Richard A.↗
NASA NTRS2009

Pressure Effects on the Self-Extinguishment Limits of Aerospace Materials

The Orion Crew Exploration Vehicle Module (CM) is being designed to operate in an atmosphere of up to 30% oxygen at a pressure of 10.2 psia for lunar missions. Spacecraft materials selection is based on an upward flammability test conducted in a closed chamber under the worst expected conditions of pressure and oxygen concentration. Material flammability depends on both oxygen concentration and pressure but, since oxygen concentration is the primary driver, all materials are certified in the 30% oxygen, 10.2 psia environment. Extensive data exist from the Shuttle Program at this condition which used relatively the same test methodology as currently used in the Constellation Program. When the CM returns to Earth, a snorkel device will be activated after splashdown to provide outside air to the crew; however, for operational reasons, it is desirable to maximize the time the crew is able to breathe cabin air before the snorkel device is activated. To maximize this time, it has been proposed to raise the partial pressure of oxygen in the CM immediately before reentry while maintaining the total cabin pressure at 14.7 psia. In addition, it has been proposed to leak-test the Orion CM with ambient air at a maximum pressure of 17.3 psia. No data exist to assess how high the cabin oxygen concentration can be at 14.7 psia or 17.3 psia. One is to re-test a large number of materials at these pressures at a significant cost. However, since the maximum oxygen concentration (MOC) at which a material will self-extinguish has been determined for a variety of spacecraft materials as a function of pressure, a second alternative is to use existing data to estimate the MOC at 14.7 psia and 17.3 psia. This data will be examined in this paper and an analysis presented to determine the oxygen concentrations at the increased pressures that will result in self-extinguishment of a material. This analysis showed that the oxygen concentration for the Orion CM at 14.7 psia cannot be set higher than 25.6% without potentially invalidating the materials flammability certification in 30% oxygen at 10.2 psia for some materials. Materials certified under these conditions would still be self-extinguishing in ambient air at 17.3 psia. alternative

Hirsch, David B.↗
NASA NTRS2007

Risk Assessment of Physiological Effects of Atmospheric Composition and Pressure in Constellation Vehicles

To reduce denitrogenation time to prevent decompression sickness to support frequent extravehicular activities on the Moon, and to limit the risk of fire, a hypobaric (P(sub B) = 414 mmHg) and mildly hypoxic (ppO2 = 132 mmHg, 32% O2 - 68% N2) living environment is being considered during lunar missions for the Crew Exploration Vehicle (CEV) and Lunar Surface Access Module (LSAM). If the vehicular ppO2 is acutely changed from 145-178 mmHg at standard vehicular operating pressure to less than 125 mmHg at desired lunar surface outpost operating pressures, there is the possibility that some crewmembers may develop symptoms of Acute Mountain Sickness (AMS). The signs and symptoms of AMS (headache plus nausea, dizziness, fatigue, or sleeplessness), could impact crew health and performance on lunar surface missions. Methods: An exhaustive literature review on the topic of the physiological effects of reduced ppO2 and absolute pressure as may contribute to the development of hypoxia and altitude symptoms or AMS. The results of the nine most rigorous studies were collated, analyzed and contents on the physiological concerns associated with hypobaric operations, AMS and hypoxia symptoms summarized. Results: Although space vehicles have operated in hypobaric conditions previously, they have not operated in a mildly hypoxic ppO2. There is evidence for an absolute pressure effect per se on AMS, such that the higher the altitude for a given hypoxic alveolar O2 partial pressure (P(sub A)O2), the greater the likelihood of an AMS response. About 25% of adults are likely to experience mild AMS near 2,000 m (xxx mmHg) altitude following a rapid ascent from sea level while breathing air (6,500 feet, acute (P(sub A)O2) = 75 mmHg). The operational experience with the Shuttle staged denitrogenation protocol at 528 mmHg (3,048 m) while breathing 26.5% O2 (acute (P(sub A)O2) = 85 mmHg) in astronauts adapting to microgravity suggests a similar likely experience in the proposed CEV environment. Conclusions: We feel that the slightly elevated risk of AMS with the recommended exploration atmospheric parameters is offset by the DCS risk reduction and improved operational efficiency offered by the hypobaric lunar surface vehicular pressure. We believe the risk of mild AMS is greater given a (P(sub A)O2) of 77 mmHg at 4,876 m altitude while breathing 32% O2 than at 1,828 m altitude while breathing 21% O2. Only susceptible astronauts would develop mild and transient AMS with prolonged exposure to 414 mmHg (4,876 m) while breathing 32% O2 (acute (P(sub A)O2) = 77 mmHg). So the following may be employed for operational risk reduction: 1) develop procedures to increase P(sub B) as needed in the CEV, and use a gradual or staged reduction in cabin pressure during lunar outbound; 2) train crews for symptoms of hypoxia, to allow early recognition and consider pre-adaptation of crews to a hypoxic environment prior to launch, 3) consider prophylactic acetazolamide for acute pressure changes and be prepared to treat any AMS associated symptoms early with both carbonic anhydrase inhibitors and supplemental oxygen.

Scheuring, Richard A.↗
NASA NTRS2000

Evaluation of Contaminant-Promoted Ignition in Scuba Equipment and Breathing Gas Delivery Systems

As the underwater diving industry continues to use greater concentrations of oxygen in their scuba systems, ignition of contaminants in these systems becomes a greater concern. Breathing gas makeup and distribution systems typically combine pure oxygen with various diluents to supply high-pressure cylinders for scuba applications. The hazards associated with these applications of oxygen and NITROX (oxygen and nitrogen mixture) gases require an evaluation of inherent contaminant levels and their associated promoted-ignition thresholds in these environments. In this study, several scuba component assemblies were tested after one year of use at the NASA Johnson Space Center Neutral Buoyancy Lab. The components were rapidly impacted with 50% NITROX gas to demonstrate their ignition resistance, then disassembled to evaluate their cleanliness. A follow-up study was then performed on the ignition thresholds of hydrocarbon-bascd oil films in oxygen and NITROX environments in an attempt to define the cleaning requirements for these systems. Stainless steel tubes were contaminated and verified to known levels and placed in a pneumatic impact test system where they were rapidly pressurized with the test gas. Ignitions were determined using a photodiode connected to the end of the contaminated tube. The results of the scuba component tests, cleanliness evaluation, and contaminant ignition study are discussed and compared for 50% NITROX and 100% oxygen environments.

Forsyth, Elliott T.↗
NASA NTRS2002

Preparing for Hiking and Rock-Climbing At Altitude

Exposure to altitude with or without exercise usually results in body dehydration. Psychological and physiological preparation for exercise at altitude involves consideration of maintaining body warmth in a cool to cold environment with progressively lower oxygen content (partial pressure) as altitude increases. However, this discussion will focus on altitudes below 14,000 it where supplemental breathing oxygen is not required for sojourns of healthy people. Background information and helpful advice for those who exercise in the cold can be found in selected articles in the 2001 Winter Issue of this Newsletter: M.B. Ducharme, Get ready for outdoor winter play: prepare yourself for the cold; C. O'Brien, Think layers when dressing for exercise in the cold; B.G. Rice and R. Ellis, Let it snow, let it snow, let it snow - but be aware of winter hazards; and L.B. Mayers, Exercise - induced asthma.

Greenleaf, John E.↗
NASA NTRS2000

Effects of whole body heating on dynamic baroreflex regulation of heart rate in humans

The purpose of this project was to identify whether dynamic baroreflex regulation of heart rate (HR) is altered during whole body heating. In 14 subjects, dynamic baroreflex regulation of HR was assessed using transfer function analysis. In normothermic and heat-stressed conditions, each subject breathed at a fixed rate (0. 25 Hz) while beat-by-beat HR and systolic blood pressure (SBP) were obtained. Whole body heating significantly increased sublingual temperature, HR, and forearm skin blood flow. Spectral analysis of HR and SBP revealed that the heat stress significantly reduced HR and SBP variability within the high-frequency range (0.2-0.3 Hz), reduced SBP variability within the low-frequency range (0.03-0.15 Hz), and increased the ratio of low- to high-frequency HR variability (all P < 0.01). Transfer function gain analysis showed that the heat stress reduced dynamic baroreflex regulation of HR within the high-frequency range (from 1.04 +/- 0.06 to 0.54 +/- 0.6 beats. min(-1). mmHg(-1); P < 0.001) without significantly affecting the gain in the low-frequency range (P = 0.63). These data suggest that whole body heating reduced high-frequency dynamic baroreflex regulation of HR associated with spontaneous changes in blood pressure. Reduced vagal baroreflex regulation of HR may contribute to reduced orthostatic tolerance known to occur in humans during heat stress.

Non-NASA Center↗
NASA NTRS2000

Physiological basis for human autonomic rhythms

Oscillations of arterial pressures, heart periods, and muscle sympathetic nerve activity have been studied intensively in recent years to explore otherwise obscure human neurophysiological mechanisms. The best-studied rhythms are those occurring at breathing frequencies. Published evidence indicates that respiratory fluctuations of muscle sympathetic nerve activity and electrocardiographic R-R intervals result primarily from the action of a central 'gate' that opens during expiration and closes during inspiration. Parallel respiratory fluctuations of arterial pressures and R-R intervals are thought to be secondary to arterial baroreflex physiology: changes in systolic pressure provoke changes in the R-R interval. However, growing evidence suggests that these parallel oscillations result from the influence of respiration on sympathetic and vagal-cardiac motoneurones rather than from baroreflex physiology. There is a rapidly growing literature on the use of mathematical models of low- and high-frequency (respiratory) R-R interval fluctuations in characterizing instantaneous 'sympathovagal balance'. The case for this approach is based primarily on measurements made with patients in upright tilt. However, the strong linear relation between such measures as the ratio of low- to high-frequency R-R interval oscillations and the angle of the tilt reflects exclusively the reductions of the vagal (high-frequency) component. As the sympathetic component does not change in tilt, the low- to high-frequency R-R interval ratio provides no proof that sympathetic activity increases. Moreover, the validity of extrapolating from measurements performed during upright tilt to measurements during supine rest has not been established. Nonetheless, it is clear that measures of heart rate variability provide important prognostic information in patients with cardiovascular diseases. It is not known whether reduced heart rate variability is merely a marker for the severity of disease or a measurement that identifies functional reflex abnormalities contributing to terminal dysrhythmias.

Review, Tutorial↗
NASA NTRS2009

Space Suit Environment Testing of the Orion Atmosphere Revitalization Technology

An amine-based carbon dioxide (CO2) and water vapor sorbent in pressure-swing regenerable beds has been developed by Hamilton Sundstrand and baselined for the Orion Atmosphere Revitalization System (ARS). In two previous years at this conference, reports were presented on extensive Johnson Space Center (JSC) testing of this technology in a sea-level pressure environment with simulated human metabolic loads. Another paper at this year s conference discusses similar testing with real human metabolic loads, including some closed-loop testing with emergency breathing masks. The Orion ARS is designed to also support extravehicular activity operations from a depressurized cabin. The next step in developmental testing at JSC was, therefore, to test this ARS technology in a typical closed space suit loop environment with low-pressure pure oxygen inside the process loop and vacuum outside the loop. This was the first instance of low-pressure oxygen loop testing of a new Orion ARS technology, and was conducted with simulated human metabolic loads in December 2008. The test investigated pressure drops through two different styles of prototype suit umbilical connectors and general swing-bed performance with both umbilical configurations as well as with a short jumper line installed in place of the umbilicals. Other interesting results include observations on the thermal effects of swing-bed operation in a vacuum environment and a recommendation of cycle time to maintain acceptable atmospheric CO2 and moisture levels.

Lin, Amy↗
NASA NTRS1989

Trajectory optimization and guidance for an aerospace plane

The first step in the approach to developing guidance laws for a horizontal take-off, air breathing single-stage-to-orbit vehicle is to characterize the minimum-fuel ascent trajectories. The capability to generate constrained, minimum fuel ascent trajectories for a single-stage-to-orbit vehicle was developed. A key component of this capability is the general purpose trajectory optimization program OTIS. The pre-production version, OTIS 0.96 was installed and run on a Convex C-1. A propulsion model was developed covering the entire flight envelope of a single-stage-to-orbit vehicle. Three separate propulsion modes, corresponding to an after burning turbojet, a ramjet and a scramjet, are used in the air breathing propulsion phase. The Generic Hypersonic Aerodynamic Model Example aerodynamic model of a hypersonic air breathing single-stage-to-orbit vehicle was obtained and implemented. Preliminary results pertaining to the effects of variations in acceleration constraints, available thrust level and fuel specific impulse on the shape of the minimum-fuel ascent trajectories were obtained. The results show that, if the air breathing engines are sized for acceleration to orbital velocity, it is the acceleration constraint rather than the dynamic pressure constraint that is active during ascent.

Mease, Kenneth D.↗
NASA NTRS2001

Survey of Advanced Booster Options for Potential Shuttle Derivative Vehicles

A never-ending major goal for the Space Shuttle program is to continually improve flight safety, as long as this launch system remains in operational service. One of the options to improve system safety and to enhance vehicle performance as well, that has been seriously studied over the past several decades, is to replace the existing strap-on four segment solid rocket boosters (SRB's) with more capable units. A number of booster upgrade options have been studied in some detail, ranging from five segment solids through hybrids and a wide variety of liquid strap-ons (both pressure and pump fed with various propellants); all the way to a completely reusable liquid fly back booster (complete with air breathing engines for controlled landing and return). All of these possibilities appear to offer improvements in varying degrees; and each has their strengths and weaknesses from both programmatic and technical points of view. The most beneficial booster upgrade/design, if the shuttle program were to continue long enough to justify the required investment, would be an approach that greatly increased both vehicle and crew safety. This would be accomplished by increasing the minimum range/minimum altitude envelope that would readily allow abort to orbit (ATO), possibly even to zero/zero, and possibly reduce or eliminate the Return to Launch Site (RTLS) and even the Trans Atlantic Landing (TAL) abort mode requirements. This paper will briefly survey and discuss all of the various booster'upgrade options studied previously, and compare their relative attributes. The survey will explicitly discuss, in summary comparative form, options that include: five segment solids; several hybrid possibilities; pressure and/or pump-fed liquids using either LO2/kerosene, H2O/kerosene and LO2/J2, any of which could be either fully expendable, partly or fully reusable; and finally a fully reusable liquid fly back booster system, with a number of propellant and propulsion system options. Performance and configuration comparison illustrations and tables will be included to provide a comprehensive survey for the paper.

Sackheim, Robert L.↗
NASA NTRS1971

Metabolic breath analyzer

Instrument measures metabolic breathing rate and dynamics of human beings in atmospheres ranging from normal air to 100 percent oxygen at ambient pressures from 14.7 to 3.0 psia. Measurements are made at rest or performing tasks up to maximum physical capacity under either zero or normal gravity.

Perry, C. L.↗
NASA NTRS2007

Testing of Full Scale Flight Qualified Kevlar Composite Overwrapped Pressure Vessels

Many decades ago NASA identified a need for low-mass pressure vessels for carrying various fluids aboard rockets, spacecraft, and satellites. A pressure vessel design known as the composite overwrapped pressure vessel (COPV) was identified to provide a weight savings over traditional single-material pressure vessels typically made of metal and this technology has been in use for space flight applications since the 1970's. A typical vessel design consisted of a thin liner material, typically a metal, overwrapped with a continuous fiber yarn impregnated with epoxy. Most designs were such that the overwrapped fiber would carry a majority of load at normal operating pressures. The weight advantage for a COPV versus a traditional singlematerial pressure vessel contributed to widespread use of COPVs by NASA, the military, and industry. This technology is currently used for personal breathing supply storage, fuel storage for auto and mass transport vehicles and for various space flight and aircraft applications. The NASA Engineering and Safety Center (NESC) was recently asked to review the operation of Kevlar 2 and carbon COPVs to ensure they are safely operated on NASA space flight vehicles. A request was made to evaluate the life remaining on the Kevlar COPVs used on the Space Shuttle for helium and nitrogen storage. This paper provides a review of Kevlar COPV testing relevant to the NESC assessment. Also discussed are some key findings, observations, and recommendations that may be applicable to the COPV user community. Questions raised during the investigations have revealed the need for testing to better understand the stress rupture life and age life of COPVs. The focus of this paper is to describe burst testing of Kevlar COPVs that has been completed as a part of an the effort to evaluate the effects of ageing and shelf life on full scale COPVs. The test articles evaluated in this discussion had a diameter of 22 inches for S/N 014 and 40 inches for S/N 011. The time between manufacture and burst was 28 and 22 years. Visual inspection, shearography, heat soak thermography and borescope inspection were performed on vessel S/N 011 and all but shearography was performed on S/N 014 before they were tested and details of this work can be found in a companion paper titled, "Nondestructive Methods and Special Test Instrumentation Supporting NASA Composite Overwrapped Pressure Vessel Assessments." The vessels were instrumented so that measurements could be made to aid in the understanding of vessel response. Measurements made on the test articles included girth, boss displacement, internal volume, multiple point strain, full field strain, eddy current, acoustic emission (AE) pressure and temperature. The test article before and during burst is shown with the pattern used for digital image correlation full field strain measurement blurring as the vessel fails.

Greene, Nathanael↗
NASA NTRSDate not supplied

2021 NE-XF Pathways Internship Student Showcase Presentation

Branch of Fluid Mechanics concern with the mechanics and properties of gases and its application to engineering systems. Applications of Pneumatics in the Aerospace systems: (1) Flight Hardware - Reaction Control, Systems, Rocket Pressure Fed Systems (2) Ground Operations – Valve Actuation, Inert Environment (Purge), Tube Drying/Cleaning NE-XFPneumatics Engineering provides design & operation expertise to support EGS. Commodities used at KSC systems: Gaseous Helium (GHe) Gaseous Oxygen (GO2) Gaseous Nitrogen (GN2) Breathing Air (BAIR) Support other subsystems: LH2, LO2, Ground Main Propulsion System (GMPS), etc.

Environmental and Life Support Systems↗