Science.gov

Sample records for pressure bar tests

  1. High Strain Rate Testing of Rocks using a Split-Hopkinson-Pressure Bar

    NASA Astrophysics Data System (ADS)

    Zwiessler, Ruprecht; Kenkmann, Thomas; Poelchau, Michael; Nau, Siegfried; Hess, Sebastian

    2016-04-01

    Dynamic mechanical testing of rocks is important to define the onset of rate dependency of brittle failure. The strain rate dependency occurs through the propagation velocity limit (Rayleigh wave speed) of cracks and their reduced ability to coalesce, which, in turn, significantly increases the strength of the rock. We use a newly developed pressurized air driven Split-Hopkinson-Pressure Bar (SHPB), that is specifically designed for the investigation of high strain rate testing of rocks, consisting of several 10 to 50 cm long strikers and bar components of 50 mm in diameter and 2.5 meters in length each. The whole set up, composed of striker, incident- and transmission bar is available in aluminum, titanium and maraging steel to minimize the acoustic impedance contrast, determined by the change of density and speed of sound, to the specific rock of investigation. Dynamic mechanical parameters are obtained in compression as well as in spallation configuration, covering a wide spectrum from intermediate to high strain rates (100-103 s‑1). In SHPB experiments [1] one-dimensional longitudinal compressive pulses of diverse shapes and lengths - formed with pulse shapers - are used to generate a variety of loading histories under 1D states of stress in cylindrical rock samples, in order to measure the respective stress-strain response at specific strain rates. Subsequent microstructural analysis of the deformed samples is aimed at quantification fracture orientation, fracture pattern, fracture density, and fracture surface properties as a function of the loading rate. Linking mechanical and microstructural data to natural dynamic deformation processes has relevance for the understanding of earthquakes, landslides, impacts, and has several rock engineering applications. For instance, experiments on dynamic fragmentation help to unravel super-shear rupture events that pervasively pulverize rocks up to several hundred meters from the fault core [2, 3, 4]. The dynamic

  2. Analysis of Hopkinson bar pressure gage. Final report

    SciTech Connect

    Baylot, J.T.

    1993-01-01

    U.S. Army Engineer Waterways Experiment Station (WES) designed Hopkinson pressure bar gages were fielded on the Dilute Explosive Tile (DET) test along with New Mexico Engineering Research Institute (NMERI) designed bar gages and pressure gages manufactured by PCB Piezotronics, Inc. On the Mineral Find 3 (MF3) explosive test, WES bar gages were fielded along with pressure transducers manufactured by Kulite. The peak pressures recorded by the PCB ages were much higher than those recorded by the WES bar gages on the DET test. The peak stresses were higher for the Kulite gages than for the WES bar gages in the MF3 test. In each of these tests, the stresses recorded later in time for the bar gage were higher than those recorded for the other types of gages. The NMERI gages indicated that the pressure time-history had two significant peaks while the WES gages indicated only one significant peak. One-half of the surviving PCB gages agreed with the WES gages, while one-half agreed with the NMERI gages. Analytical and finite element (FE) calculations were performed to assess the response of the bar gages in these tests. The analytical solutions included only the bar and agreed extremely well with comparable FE calculations. These calculations indicated that the primary reason for the low peak stress readings in the bar gages was the lower frequency response capability of the recording system used to record the bar gage data. The calculations also indicated that the presence of water around the bar did not significantly affect the measured peak stress in the bar, and that the drag of the water past the bar did not cause significant forces to be developed in the bar.

  3. Geomechanics of penetration :laboratory analog experiments using a modified split hopkinson pressure bar/impact testing procedure.

    SciTech Connect

    Holcomb, David Joseph; Gettemy, Glen L.; Bronowski, David R.

    2005-11-01

    This research continues previous efforts to re-focus the question of penetrability away from the behavior of the penetrator itself and toward understanding the dynamic, possibly strain-rate dependent, behavior of the affected materials. A modified split Hopkinson pressure bar technique is prototyped to determine the value of reproducing the stress states, and mechanical responses, of geomaterials observed in actual penetrator tests within a laboratory setting. Conceptually, this technique simulates the passage of the penetrator surface past any fixed point in the penetrator trajectory by allowing for a controlled stress-time function to be transmitted into a sample, thereby mimicking the 1D radial projection inherent to analyses of the cavity expansion problem. Test results from a suite of weak (unconfined compressive strength, or UCS, of 22 MPa) concrete samples, with incident strain rates of 100-250 s{sup -1}, show that the complex mechanical response includes both plastic and anelastic wave propagation, and is critically dependent on incident particle velocity and saturation state. For instance, examination of the transmitted stress-time data, and post-test volumetric measurements of pulverized material, provide independent estimates of the plasticized zone length (1-2 cm) formed for incident particle velocity of {approx}16.7 m/s. The results also shed light on the elastic or energy propagation property changes that occur in the concrete. For example, the pre- and post-test zero-stress elastic wave propagation velocities show that the Young's modulus drops from {approx}19 GPa to <8 GPa for material within the first centimeter from the plastic transition front, while the Young's modulus of the dynamically confined, axially-stressed (in 6-18 MPa range) plasticized material drops to 0.5-0.6 GPa. The data also suggest that the critical particle velocity for formation of a plastic zone in the weak concrete is 13-15 m/s, with increased saturation tending to increase

  4. A piezo-bar pressure probe

    NASA Technical Reports Server (NTRS)

    Friend, W. H.; Murphy, C. L.; Shanfield, I.

    1967-01-01

    Piezo-bar pressure type probe measures the impact velocity or pressure of a moving debris cloud. It measures pressures up to 200,000 psi and peak pressures may be recorded with a total pulse duration between 5 and 65 musec.

  5. New experimental techniques with the split Hopkinson pressure bar

    SciTech Connect

    Frantz, C.E.; Follansbee, P.S.; Wright, W.J.

    1984-01-01

    The split Hopkinson pressure bar or Kolsky bar has provided for many years a technique for performing compression tests at strain rates approaching 10/sup 4/ s/sup -1/. At these strain rates, the small dimensions possible in a compression test specimen give an advantage over a dynamic tensile test by allowing the stress within the specimen to equilibrate within the shortest possible time. The maximum strain rates possible with this technique are limited by stress wave propagation in the elastic pressure bars as well as in the deforming specimen. This subject is reviewed in this paper, and it is emphasized that a slowly rising excitation is preferred to one that rises steeply. Experimental techniques for pulse shaping and a numerical procedure for correcting the raw data for wave dispersion in the pressure bars are presented. For tests at elevated temperature a bar mover apparatus has been developed which effectively brings the cold pressure bars into contact with the specimen, which is heated with a specially designed furnace, shortly before the pressure wave arrives. This procedure has been used successfully in tests at temperatures as high as 1000/sup 0/C.

  6. CFD Modeling of the Multipurpose Hydrogen Test Bed (MHTB) Self-Pressurization and Spray Bar Mixing Experiments in Normal Gravity: Effect of Accommodation Coefficient on the Tank Pressure

    NASA Technical Reports Server (NTRS)

    Kartuzova, Olga; Kassemi, Mohammad

    2015-01-01

    In this paper, a computational model that describes pressure control phase of a typical MHTB experiment will be presented. The fidelity of the model will be assessed by comparing the models predictions with MHTB experimental data. In this paper CFD results for MHTB spray bar cooling case with 50 tank fill ratio will be presented and analyzed. Effect of accommodation coefficient for calculating droplet-ullage mass transfer will be evaluated.

  7. Blast Quantification Using Hopkinson Pressure Bars.

    PubMed

    Clarke, Samuel D; Fay, Stephen D; Rigby, Samuel E; Tyas, Andrew; Warren, James A; Reay, Jonathan J; Fuller, Benjamin J; Gant, Matthew T A; Elgy, Ian D

    2016-01-01

    Near-field blast load measurement presents an issue to many sensor types as they must endure very aggressive environments and be able to measure pressures up to many hundreds of megapascals. In this respect the simplicity of the Hopkinson pressure bar has a major advantage in that while the measurement end of the Hopkinson bar can endure and be exposed to harsh conditions, the strain gauge mounted to the bar can be affixed some distance away. This allows protective housings to be utilized which protect the strain gauge but do not interfere with the measurement acquisition. The use of an array of pressure bars allows the pressure-time histories at discrete known points to be measured. This article also describes the interpolation routine used to derive pressure-time histories at un-instrumented locations on the plane of interest. Currently the technique has been used to measure loading from high explosives in free air and buried shallowly in various soils. PMID:27404117

  8. Numerical Investigation of Dynamic Rock Fracture Toughness Determination Using a Semi-Circular Bend Specimen in Split Hopkinson Pressure Bar Testing

    NASA Astrophysics Data System (ADS)

    Xu, Y.; Dai, F.; Xu, N. W.; Zhao, T.

    2016-03-01

    The International Society for Rock Mechanics (ISRM) has suggested a notched semi-circular bend technique in split Hopkinson pressure bar (SHPB) testing to determine the dynamic mode I fracture toughness of rock. Due to the transient nature of dynamic loading and limited experimental techniques, the dynamic fracture process associated with energy partitions remains far from being fully understood. In this study, the dynamic fracturing of the notched semi-circular bend rock specimen in SHPB testing is numerically simulated for the first time by the discrete element method (DEM) and evaluated in both microlevel and energy points of view. The results confirm the validity of this DEM model to reproduce the dynamic fracturing and the feasibility to simultaneously measure key dynamic rock fracture parameters, including initiation fracture toughness, fracture energy, and propagation fracture toughness. In particular, the force equilibrium of the specimen can be effectively achieved by virtue of a ramped incident pulse, and the fracture onset in the vicinity of the crack tip is found to synchronize with the peak force, both of which guarantee the quasistatic data reduction method employed to determine the dynamic fracture toughness. Moreover, the energy partition analysis indicates that simplifications, including friction energy neglect, can cause an overestimation of the propagation fracture toughness, especially under a higher loading rate.

  9. Using the split Hopkinson pressure bar to validate material models

    PubMed Central

    Church, Philip; Cornish, Rory; Cullis, Ian; Gould, Peter; Lewtas, Ian

    2014-01-01

    This paper gives a discussion of the use of the split-Hopkinson bar with particular reference to the requirements of materials modelling at QinetiQ. This is to deploy validated material models for numerical simulations that are physically based and have as little characterization overhead as possible. In order to have confidence that the models have a wide range of applicability, this means, at most, characterizing the models at low rate and then validating them at high rate. The split Hopkinson pressure bar (SHPB) is ideal for this purpose. It is also a very useful tool for analysing material behaviour under non-shock wave loading. This means understanding the output of the test and developing techniques for reliable comparison of simulations with SHPB data. For materials other than metals comparison with an output stress v strain curve is not sufficient as the assumptions built into the classical analysis are generally violated. The method described in this paper compares the simulations with as much validation data as can be derived from deployed instrumentation including the raw strain gauge data on the input and output bars, which avoids any assumptions about stress equilibrium. One has to take into account Pochhammer–Chree oscillations and their effect on the specimen and recognize that this is itself also a valuable validation test of the material model. PMID:25071238

  10. Using the split Hopkinson pressure bar to validate material models.

    PubMed

    Church, Philip; Cornish, Rory; Cullis, Ian; Gould, Peter; Lewtas, Ian

    2014-08-28

    This paper gives a discussion of the use of the split-Hopkinson bar with particular reference to the requirements of materials modelling at QinetiQ. This is to deploy validated material models for numerical simulations that are physically based and have as little characterization overhead as possible. In order to have confidence that the models have a wide range of applicability, this means, at most, characterizing the models at low rate and then validating them at high rate. The split Hopkinson pressure bar (SHPB) is ideal for this purpose. It is also a very useful tool for analysing material behaviour under non-shock wave loading. This means understanding the output of the test and developing techniques for reliable comparison of simulations with SHPB data. For materials other than metals comparison with an output stress v strain curve is not sufficient as the assumptions built into the classical analysis are generally violated. The method described in this paper compares the simulations with as much validation data as can be derived from deployed instrumentation including the raw strain gauge data on the input and output bars, which avoids any assumptions about stress equilibrium. One has to take into account Pochhammer-Chree oscillations and their effect on the specimen and recognize that this is itself also a valuable validation test of the material model. PMID:25071238

  11. Numerical Simulations of the Kolsky Compression Bar Test

    SciTech Connect

    Corona, Edmundo

    2015-10-01

    The Kolsky compression bar, or split Hopkinson pressure bar (SHPB), is an ex- perimental apparatus used to obtain the stress-strain response of material specimens at strain rates in the order of 10 2 to 10 4 1/s. Its operation and associated data re- duction are based on principles of one-dimensional wave propagation in rods. Second order effects such as indentation of the bars by the specimen and wave dispersion in the bars, however, can significantly affect aspects of the measured material response. Finite element models of the experimental apparatus were used here to demonstrate these two effects. A procedure proposed by Safa and Gary (2010) to account for bar indentation was also evaluated and shown to improve the estimation of the strain in the bars significantly. The use of pulse shapers was also shown to alleviate the effects of wave dispersion. Combining the two can lead to more reliable results in Kolsky compression bar testing.

  12. Experimental and numerical investigations on the use of polymer Hopkinson pressure bars.

    PubMed

    Harrigan, John J; Ahonsi, Bright; Palamidi, Elisavet; Reid, Steve R

    2014-08-28

    Split Hopkinson pressure bar (SHPB) testing has traditionally been carried out using metal bars. For testing low stiffness materials such as rubbers or low strength materials such as low density cellular solids considered primarily herein, there are many advantages to replacing the metal bars with polymer bars. An investigation of a number of aspects associated with the accuracy of SHPB testing of these materials is reported. Test data are used to provide qualitative comparisons of accuracy using different bar materials and wave-separation techniques. Sample results from SHPB tests are provided for balsa, Rohacell foam and hydroxyl-terminated polybutadiene. The techniques used are verified by finite-element (FE) analysis. Experimentally, the material properties of the bars are determined from impact tests in the form of a complex elastic modulus without curve fitting to a rheological model. For the simulations, a rheological model is used to define the bar properties by curve fitting to the experimentally derived properties. Wave propagation in a polymer bar owing to axial impact of a steel bearing ball is simulated. The results indicate that the strain histories can be used to determine accurately the viscoelastic properties of polymer bars. An FE model of the full viscoelastic SHPB set-up is then used to simulate tests on hyperelastic materials. PMID:25071237

  13. Two-wave photon Doppler velocimetry measurements in direct impact Hopkinson pressure bar experiments

    NASA Astrophysics Data System (ADS)

    Lea, Lewis J.; Jardine, Andrew P.

    2015-09-01

    Direct impact Hopkinson pressure bar systems offer many potential advantages over split Hopkinson pressure bars, including access to higher strain rates, higher strains for equivalent striker velocity and system length, lower dispersion and faster achievement of force equilibrium. Currently advantages are gained at a significant cost: the fact that input bar data is unavailable removes all information about the striker impacted specimen face, preventing the determination of force equilibrium, and requiring approximations to be made on the sample deformation history. Recently photon Doppler velocimetry methods have been developed, which can replace strain gauges on Hopkinson bars. In this paper we discuss an experimental method and complementary data analysis for using Doppler velocimetry to measure surface velocities of the striker and output bars in a direct impact bar experiment, allowing similar data to be recorded as in a split bar system, with the same level of convenience. We discuss extracting velocity and force measurements, and improving the accuracy and convenience of Doppler velocimetry on Hopkinson bars. Results obtained using the technique are compared to equivalent split bar tests, showing improved stress measurements for the lowest and highest strains.

  14. On backward dispersion correction of Hopkinson pressure bar signals

    PubMed Central

    Tyas, A.; Ozdemir, Z.

    2014-01-01

    Elastic theory shows that wide spectrum signals in the Hopkinson pressure bar suffer two forms of distortion as they propagate from the loaded bar face. These must be accounted for if accurate determination of the impact load is to be possible. The first form of distortion is the well-known phase velocity dispersion effect. The second form, which can be equally deleterious, is the prediction that at high frequencies, the stress and strain generated in the bar varies with radial position on the cross section, even for a uniformly applied loading. We consider the consequences of these effects on our ability to conduct accurate backward dispersion correction of bar signals, that is, to derive the impact face load from the dispersed signal recorded at some other point on the bar. We conclude that there is an upper limit on the frequency for which the distortion effects can be accurately compensated, and that this can significantly affect the accuracy of experimental results. We propose a combination of experimental studies and detailed numerical modelling of the impact event and wave propagation along the bar to gain better understanding of the frequency content of the impact event, and help assess the accuracy of experimental predictions of impact face load. PMID:25071236

  15. CFD Modeling of the Multipurpose Hydrogen Test Bed (MHTB) Self-Pressurization and Spray Bar Mixing Experiments in Normal Gravity: Effect of the Accommodation Coefficient on the Tank Pressure

    NASA Technical Reports Server (NTRS)

    Kartuzova, Olga; Kassemi, Mohammad

    2015-01-01

    A CFD model for simulating the self-pressurization of a large scale liquid hydrogen storage tank is utilized in this paper to model the MHTB self-pressurization experiment. The kinetics-based Schrage equation is used to account for the evaporative and condensi ng interfacial mass flows in this model. The effect of the accommodation coefficient for calculating the interfacial mass transfer rate on the tank pressure during tank selfpressurization is studied. The values of the accommodation coefficient which were considered in this study vary from 1.0e-3 to 1.0e-1 for the explicit VOF model and from 1.0e-4 to 1.0e-3 for the implicit VOF model. The ullage pressure evolutions are compared against experimental data. A CFD model for controlling pressure in cryogenic storage tanks by spraying cold liquid into the ullage is also presented. The Euler-Lagrange approach is utilized for tracking the spray droplets and for modeling the interaction between the droplets and the continuous phase (ullage). The spray model is coupled with the VOF model by performing particle tracking in the ullage, removing particles from the ullage when they reach the interface, and then adding their contributions to the liquid. Droplet-ullage heat and mass transfer are modeled. The flow, temperature, and interfacial mass flux, as well as droplets trajectories, size distribution and temperatures predicted by the model are presented. The ul lage pressure and vapor temperature evolutions are compared with experimental data obtained from the MHTB spray bar mixing experiment. The effect of the accommodation coefficient for calculating the interfacial and droplet mass transfer rates on the tank pressure during mixing of the vapor using spray is studied. The values used for the accommodation coefficient at the interface vary from 1.0e-5 to 1.0e-2. The droplet accommodation coefficient values vary from 2.0e-6 to 1.0e-4.

  16. Application of photon Doppler velocimetry to direct impact Hopkinson pressure bars.

    PubMed

    Lea, Lewis J; Jardine, Andrew P

    2016-02-01

    Direct impact Hopkinson pressure bar systems offer many potential advantages over split Hopkinson pressure bars, including access to higher strain rates, higher strains for equivalent striker velocity and system length, lower dispersion, and faster achievement of force equilibrium. Currently, these advantages are gained at the expense of all information about the striker impacted specimen face, preventing the experimental determination of force equilibrium, and requiring approximations to be made on the sample deformation history. In this paper, we discuss an experimental method and complementary data analysis for using photon Doppler velocimetry to measure surface velocities of the striker and output bars in a direct impact bar experiment, allowing similar data to be recorded as in a split bar system. We discuss extracting velocity and force measurements, and the precision of measurements. Results obtained using the technique are compared to equivalent split bar tests, showing improved stress measurements for the lowest and highest strains in fully dense metals, and improvement for all strains in slow and non-equilibrating materials. PMID:26931828

  17. Application of photon Doppler velocimetry to direct impact Hopkinson pressure bars

    NASA Astrophysics Data System (ADS)

    Lea, Lewis J.; Jardine, Andrew P.

    2016-02-01

    Direct impact Hopkinson pressure bar systems offer many potential advantages over split Hopkinson pressure bars, including access to higher strain rates, higher strains for equivalent striker velocity and system length, lower dispersion, and faster achievement of force equilibrium. Currently, these advantages are gained at the expense of all information about the striker impacted specimen face, preventing the experimental determination of force equilibrium, and requiring approximations to be made on the sample deformation history. In this paper, we discuss an experimental method and complementary data analysis for using photon Doppler velocimetry to measure surface velocities of the striker and output bars in a direct impact bar experiment, allowing similar data to be recorded as in a split bar system. We discuss extracting velocity and force measurements, and the precision of measurements. Results obtained using the technique are compared to equivalent split bar tests, showing improved stress measurements for the lowest and highest strains in fully dense metals, and improvement for all strains in slow and non-equilibrating materials.

  18. Telescoping magnetic ball bar test gage

    DOEpatents

    Bryan, J.B.

    1984-03-13

    A telescoping magnetic ball bar test gage for determining the accuracy of machine tools, including robots, and those measuring machines having non-disengageable servo drives which cannot be clutched out is disclosed. Two gage balls are held and separated from one another by a telescoping fixture which allows them relative radial motional freedom but not relative lateral motional freedom. The telescoping fixture comprises a parallel reed flexure unit and a rigid member. One gage ball is secured by a magnetic socket knuckle assembly which fixes its center with respect to the machine being tested. The other gage ball is secured by another magnetic socket knuckle assembly which is engaged or held by the machine in such manner that the center of that ball is directed to execute a prescribed trajectory, all points of which are equidistant from the center of the fixed gage ball. As the moving ball executes its trajectory, changes in the radial distance between the centers of the two balls caused by inaccuracies in the machine are determined or measured by a linear variable differential transformer (LVDT) assembly actuated by the parallel reed flexure unit. Measurements can be quickly and easily taken for multiple trajectories about several different fixed ball locations, thereby determining the accuracy of the machine. 3 figs.

  19. Telescoping magnetic ball bar test gage

    DOEpatents

    Bryan, James B.

    1984-01-01

    A telescoping magnetic ball bar test gage for determining the accuracy of machine tools, including robots, and those measuring machines having non-disengageable servo drives which cannot be clutched out. Two gage balls (10, 12) are held and separated from one another by a telescoping fixture which allows them relative radial motional freedom but not relative lateral motional freedom. The telescoping fixture comprises a parallel reed flexure unit (14) and a rigid member (16, 18, 20, 22, 24). One gage ball (10) is secured by a magnetic socket knuckle assembly (34) which fixes its center with respect to the machine being tested. The other gage ball (12) is secured by another magnetic socket knuckle assembly (38) which is engaged or held by the machine in such manner that the center of that ball (12) is directed to execute a prescribed trajectory, all points of which are equidistant from the center of the fixed gage ball (10). As the moving ball (12) executes its trajectory, changes in the radial distance between the centers of the two balls (10, 12) caused by inaccuracies in the machine are determined or measured by a linear variable differential transformer (LVDT) assembly (50, 52, 54, 56, 58, 60) actuated by the parallel reed flexure unit (14). Measurements can be quickly and easily taken for multiple trajectories about several different fixed ball (10) locations, thereby determining the accuracy of the machine.

  20. Telescoping magnetic ball bar test gage

    DOEpatents

    Bryan, J.B.

    1982-03-15

    A telescoping magnetic ball bar test gage for determining the accuracy of machine tools, including robots, and those measuring machines having non-disengagable servo drives which cannot be clutched out. Two gage balls are held and separated from one another by a telescoping fixture which allows them relative radial motional freedom but not relative lateral motional freedom. The telescoping fixture comprises a parallel reed flexure unit and a rigid member. One gage ball is secured by a magnetic socket knuckle assembly which fixes its center with respect to the machine being tested. The other gage ball is secured by another magnetic socket knuckle assembly which is engaged or held by the machine in such manner that the center of that ball is directed to execute a prescribed trajectory, all points of which are equidistant from the center of the fixed gage ball. As the moving ball executes its trajectory, changes in the radial distance between the centers of the two balls caused by inaccuracies in the machine are determined or measured by a linear variable differential transformer (LVDT) assembly actuated by the parallel reed flexure unit. Measurements can be quickly and easily taken for multiple trajectories about several different fixed ball locations, thereby determining the accuracy of the machine.

  1. Flange weld pressure testing

    NASA Technical Reports Server (NTRS)

    Holden, C. F.

    1977-01-01

    Device allows localized high-pressure proof test. Use of tool eliminates need to block off far end of pipe; only small amount of pressurizing gas is needed; only small area needs to be cleared of personnel for proof test.

  2. Testing of a Spray-bar Thermodynamic Vent System in Liquid Nitrogen

    NASA Technical Reports Server (NTRS)

    Flachbart, R. H.; Hastings, L. J.; Hedayat, A.; Nelson, S. L.; Tucker, S. P.

    2005-01-01

    To support development of a microgravity pressure control capability for liquid oxygen, thermodynamic vent system (TVS) testing was conducted at Marshall Space Flight Center (MSFC) using liquid nitrogen (LN2) as a LOX simulant. The spray bar TVS hardware used was originally designed by the Boeing Company for testing in liquid hydrogen (LH2). With this concept, a small portion of the tank fluid is passed through a Joule-Thomson (J-T) device, and then through a longitudinal spray bar mixed-heat exchanger in order to cool the bulk fluid. To accommodate the larger mass flow rates associated with LN2, the TVS hardware was modified by replacing the recirculation pump with an LN2 compatible pump and replacing the J-T valve. The primary advantage of the spray-bar configuration is that tank pressure control can be achieved independent of liquid and vapor location, enhancing the applicability of ground test data to microgravity conditions. Performance testing revealed that the spray-bar TVS was effective in controlling tank pressure within a 6.89 kPa band for fill levels of 90%, 50%, and 25%. Tests were also conducted with gaseous helium (GHe) in the ullage. The TVS operated nominally with GHe in the ullage, with performance similar to the tests with gaseous nitrogen (GN2). Testing demonstrated that the spray-bar TVS design was flexible enough for use in two different propellants with minimal hardware modifications.

  3. An experimental technique of split Hopkinson pressure bar using fiber micro-displacement interferometer system for any reflector

    NASA Astrophysics Data System (ADS)

    Fu, H.; Tang, X. R.; Li, J. L.; Tan, D. W.

    2014-04-01

    A novel non-contact measurement technique had been developed for the mechanical properties of materials in Split Hopkinson Pressure Bars (SHPB). Instead of the traditional strain gages mounted on the surfaces of bars, two shutters were mounted on the end of bars to directly measure interfacial velocity using Fiber Micro-Displacement Interferometer System for Any Reflector. Using the new technique, the integrated stress-strain responses could be determined. The experimental technique was validated by SHPB test simulation. The technique had been used to investigate the dynamic response of a brittle explosive material. The results showed that the new experimental technique could be applied to the dynamic behavior in SHPB test.

  4. ECN Pressure Test

    SciTech Connect

    Dixon, K.; /Fermilab

    1991-07-18

    This note describes: the rationale for the test pressure of the inner ECN cryostat vessel, the equipment to be used in this test, the test procedure, the status of the vessel prior to the test, the actual test results, and a schematic diagram of the testing set up and the pressure testing permit. The test, performed in the evening of July 17, 1991, was a major success. Based on a neglible pressure drop indicated on the pressure gages (1/4 psi), the vessel appeared to be structurally sound throughout the duration of the test (approx. 1.5 hrs.). No pressure increases were observed on the indicators looking at the beam tube bellows volumes. There was no indication of bubbles form the soap test on the welds and most of the fittings that were checked. There were some slight deviations in the actual procedure used. The UO filter was removed after the vessel had bled down to about 18 psig in order to speed up that aspect of the test. The rationale was that the higher velocity gas had already passed through at the higher pressures and there was no visible traces of the black uo particles. The rate of 4 psi/10 minutes seemed incredibly slow and often that time was reduced to just over half that rate. The testing personnel was allowed to stay in the pit throughout the duration of the test; this was a slight relaxation of the rules.

  5. CC Pressure Test

    SciTech Connect

    Dixon, K.; /Fermilab

    1990-07-12

    The inner vessel heads including bypass and beam tubes had just been welded into place and dye penetrant checked. The vacuum heads were not on at this time but the vacuum shell was on covering the piping penetrating into the inner vessel. Signal boxes with all feed through boards, the instrumentation box, and high voltage boxes were all installed with their pump outs capped. All 1/4-inch instrumentation lines were terminated at their respective shutoff valves. All vacuum piping used for pumping down the inner vessel was isolated using o-ring sealed blind flanges. PV215A (VAT Series 12), the 4-inch VRC gate valve isolating the cyropump, and the rupture disk had to be removed and replaced with blind flanges before pressurizing due to their pressure limitations. Stresses in plates used as blind flanges were checked using Code calcualtions. Before the CC test, vacuum style blanks and clamps were hydrostatically pressure tested to 150% of the maximum test pressure, 60 psig. The Code inspector and Research Division Safety had all given their approval to the test pressure and procedure prior to filling the vessel with argon. The test was a major success. Based on the lack of any distinguishable pressure drop indicated on the pressure gages, the vessel appeared to be structurally sound throughout the duration of the test (approx. 3 hrs.). A major leak in the instrumentation tubing was discovered at half of the maximum test pressure and was quickly isolated by crimping and capping with a compression fitting. There were some slight deviations in the actual procedure used. The 44 psig relief valve located just outside the cleanroom had to be capped until the pressure in the vessel indicated 38 psi. This was to allow higher supply pressures and hence, higher flows through the pressurizing line. Also, in order to get pressure readings at the cryostat without exposing any personnel to the potentially dangerous stored energy near the maximum test pressure, a camera was installed

  6. Automated optical manufacturing test system for high power multi- bar diode modules

    NASA Astrophysics Data System (ADS)

    Bhadra, Sriraj K.; Humble, Chuck; Nguyen, Hoa; Treusch, Georg; Pandey, Rajiv; Bell, John

    2005-11-01

    This paper describes an innovative, high throughput manufacturing test system for testing high power laser-diode stacks. These stacks are based on a single high power bar building block, which can be stacked either vertically or horizontally to deliver extremely high output power (>3kW) from a compact package which can range from a single bar to over 25 bars in one package. Testing these various form-factors presents many challenges in high-volume manufacturing e.g. repeated changes of tooling and set-up to accommodate mixture of configurations. The automated test system described in this paper can accommodate any configuration of multi-bar stacks to test critical optical characteristics (LIV, Optical Spectrum Characteristics, Optical Power, Optical Divergence, water flow rate, water pressure etc.). Key to the automated station is a custom designed integrating sphere and universal stack holder with automated water flow configuration. The automated test system significantly improves the throughput by decreasing the test time by 50% (compared to manual testing). Individual bars comprising stack have different spectrum and the custom designed integrating sphere enables accurate spectrum analysis (centroid wavelength, FWHM) of the combined spectrum, as well as accurate power measurement.

  7. Shear viscosity of shocked metals at mega-bar pressures

    NASA Astrophysics Data System (ADS)

    Liu, Fu-Sheng

    2013-06-01

    Viscosity of metals at high pressures and temperatures has been one of the most concerned problems in weapon physics and geophysics, e.g., the shear viscosity coefficients of substances in earth's mantle and earth's core at mega-bar pressures are needed for understanding the core mantle convection in deep earth. But the experimental data is very scarce because the conventional measurement methods can hardly be applied to such compression conditions [1]. In this talk, the principle of small-disturbance perturbation method [2] is re-investigated based on both the analytic solution and the numerical solution of the two-dimentional shock flow of sinusoidal distubance on front. In numerical solution, the real viscosity, which governs the flow behind the shock front and the perturbation damping feature, and the artificial viscosity, whick controls the numerical oscillation, separately treated. The relation between the viscosity of flow and the damping features of perturbation amplitude is quantitatively established for the loading situations of Sakharov's [3] and a flyer-impact situation with a finite disturbance. The later is the theoretical basis to develop a new experimental method, called the flyer-impact small-disturbance method [4]. In the flyer-impact small-disturbance method, the two-stage light-gas gun is used to launch a metal flyer. When the flyer directly impacts on the wedge-shaped sample with a sinusoidal surface, a two-dimensional shock flow of sinusoidal distubance on its front is generated. The amplitude of disturbance and its dependance with propagation distance is measured by use of an electric pin-array probe or a fibre-array probe. Correspondingly, the solution of the flow is given by numerically solving the hydrodynamic equations by the finite difference technique to find out the quantative correlations among the amplitude decay, the initial distribution of flow, the amplitude of initial disturbance, the shear viscosity of the flow, and the material

  8. Hopkinson pressure bar set-up for the measurement of Bauschinger effect under dynamic loading

    NASA Astrophysics Data System (ADS)

    Ruggiero, Andrew; Bonora, Nicola; Iannitti, Gianluca

    2013-06-01

    Metals and alloys show different stress-strain characteristics under reverse loading cycle (Bauschinger effect). The knowledge of the effective material response is important in impact dynamics where material is subjected to compression-tension loading as a result of stress wave propagation. In this paper an experimental set-up of the Hopkinson pressure bar to characterize the material response under dynamic loading cycle is presented. In the proposed configuration, in one single test, the sample is subjected to tension and compression loading with same absolute stress intensity and duration. Also this solution allows the possibility to select the load cycle sequence (tension-compression or compression-tension). Relationships to determine the stress, strain rate and strain from the elastic signals at the bars which are also effective for the second stress pulse, are presented. The method was verified with FEM and used to determine the Bauschinger effect for AISI 316L stainless steel.

  9. Strain rate change tests with the Split Hopkinson Bar method

    NASA Astrophysics Data System (ADS)

    Isakov, M.; Kokkonen, J.; Östman, K.; Kuokkala, V.-T.

    2016-05-01

    In this paper, methods to produce rapid strain rate changes for strain rate sensitivity measurements in Split Hopkinson Bar arrangements are presented and discussed. Two different cases are considered: a strain rate change test within the high strain rate region in compression, and a tension test incorporating a large strain rate jump directly from the low strain rate region to high strain rates. The former method is based on the loading wave amplitude manipulation, while the latter method is based on the incorporation of a low strain rate loading device into a Tensile Split Hopkinson Bar apparatus.

  10. 8. Photocopied August 1978. BREAKING CONCRETE BARS, JULY 1898. TESTING ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    8. Photocopied August 1978. BREAKING CONCRETE BARS, JULY 1898. TESTING MACHINE USED BY VON SCHON IN EXPERIMENTS ON METHODS OF MIXING CONCRETE AND ON CONCRETE AGGREGATES WHICH USED LOCAL MATERIALS. (4) - Michigan Lake Superior Power Company, Portage Street, Sault Ste. Marie, Chippewa County, MI

  11. Raising the Bar: Increased Hydraulic Pressure Allows Unprecedented High Power Densities in Pressure-Retarded Osmosis

    SciTech Connect

    Straub, AP; Yip, NY; Elimelech, M

    2014-01-01

    Pressure-retarded osmosis (PRO) has the potential to generate sustainable energy from salinity gradients. PRO is typically considered for operation with river water and seawater, but a far greater energy of mixing can be harnessed from hypersaline solutions. This study investigates the power density that can be obtained in PRO from such concentrated solutions. Thin-film composite membranes with an embedded woven mesh were supported by tricot fabric feed spacers in a specially designed crossflow cell to maximize the operating pressure of the system, reaching a stable applied hydraulic pressure of 48 bar (700 psi) for more than 10 h. Operation at this increased hydraulic pressure allowed unprecedented power densities, up to 60 W/m(2) with a 3 M (180 g/L) NaCl draw solution. Experimental power densities demonstrate reasonable agreement with power densities modeled using measured membrane properties, indicating high-pressure operation does not drastically alter membrane performance. Our findings exhibit the promise of the generation of power from high-pressure PRO with concentrated solutions.

  12. An experimental technique of split Hopkinson pressure bar using fiber micro-displacement interferometer system for any reflector.

    PubMed

    Fu, H; Tang, X R; Li, J L; Tan, D W

    2014-04-01

    A novel non-contact measurement technique had been developed for the mechanical properties of materials in Split Hopkinson Pressure Bars (SHPB). Instead of the traditional strain gages mounted on the surfaces of bars, two shutters were mounted on the end of bars to directly measure interfacial velocity using Fiber Micro-Displacement Interferometer System for Any Reflector. Using the new technique, the integrated stress-strain responses could be determined. The experimental technique was validated by SHPB test simulation. The technique had been used to investigate the dynamic response of a brittle explosive material. The results showed that the new experimental technique could be applied to the dynamic behavior in SHPB test. PMID:24784672

  13. Acoustic emission monitoring of hot functional testing: Watts Bar Unit 1 Nuclear Reactor

    SciTech Connect

    Hutton, P.H.; Dawson, J.F.; Friesel, M.A.; Harris, J.C.; Pappas, R.A.

    1984-06-01

    Acoustic emission (AE) monitoring of selected pressure boundary areas at TVA's Watts Bar, Unit 1 Nuclear Power Plant during hot functional preservice testing is described in this report. The report deals with background, methodology, and results. The work discussed here is a major milestone in a program supported by NRC to develop and demonstrate application of AE monitoring for continuous surveillance of reactor pressure boundaries to detect and evaluate growing flaws. The subject work demonstrated that anticipated problem areas can be overcome. Work is continuing toward AE monitoring during reactor operation.

  14. Pressure locking test results

    SciTech Connect

    DeWall, K.G.; Watkins, J.C.; McKellar, M.G.; Bramwell, D.

    1996-12-01

    The U.S. Nuclear Regulatory Commission (NRC), Office of Nuclear Regulatory Research, is funding the Idaho National Engineering Laboratory (INEL) in performing research to provide technical input for their use in evaluating responses to Generic Letter 95-07, {open_quotes}Pressure Locking and Thermal Binding of Safety-Related Power-Operated Gate Valves.{close_quotes} Pressure locking and thermal binding are phenomena that make a closed gate valve difficult to open. This paper discusses only the pressure locking phenomenon in a flexible-wedge gate valve; the authors will publish the results of their thermal binding research at a later date. Pressure locking can occur when operating sequences or temperature changes cause the pressure of the fluid in the bonnet (and, in most valves, between the discs) to be higher than the pressure on the upstream and downstream sides of the disc assembly. This high fluid pressure presses the discs against both seats, making the disc assembly harder to unseat than anticipated by the typical design calculations, which generally consider friction at only one of the two disc/seat interfaces. The high pressure of the bonnet fluid also changes the pressure distribution around the disc in a way that can further contribute to the unseating load. If the combined loads associated with pressure locking are very high, the actuator might not have the capacity to open the valve. The results of the NRC/INEL research discussed in this paper show that the relationship between bonnet pressure and pressure locking stem loads appears linear. The results also show that for this valve, seat leakage affects the bonnet pressurization rate when the valve is subjected to thermally induced pressure locking conditions.

  15. Response of the Watts Bar, Maine Yankee and Bellefonte containments to static internal pressurization

    SciTech Connect

    Jung, J.

    1983-01-01

    As part of Sandia National Laboratories' Severe Accident Sequence Analysis (SASA) Program, structural analyses of the Watts Bar, Maine Yankee and Bellefonte containment structures were performed with the objective of obtaining realistic estimates of their ultimate static pressure capabilities. The Watts Bar investigation included analyses of the containment shell, equipment hatch, anchorage systems and personnel lock. The ultimate pressure capability is estimated to be between 120 and 140 psig, corresponding to shell yielding and equipment hatch buckling, respectively. The Maine Yankee investigation provided a 96 to 118 psig failure pressure estimate for the containment shell. The pressure capability of the Bellefonte containment structure is estimated to be between 130 and 139 psig corresponding to dome tendon yielding and cylinder wall tendon yielding, respectively.

  16. IMPROVED BAR IMPACT TESTS USING A PHOTONIC DOPPLER VELOCIMETER

    SciTech Connect

    Bless, S J; Tolman, J; Levinson, S; Nguyen, J

    2009-08-24

    Bar impact tests, using the techniques described elsewhere in this symposium, were used to measure compressive and tensile strengths of borosilicate glass, soda lime glass, and a glass ceramic. The glass ceramic was 25% crystalline spinel, furnished by Corning Inc. There are two measures of compressive strength: the peak stress that can be transmitted in unconfined compression, and the 'steady state' strength. For borosilicate glass and soda lime glass, these values were similar, being about 1.8 and 1.5 GPa, respectively. The glass ceramic (25% spinel) was almost 50% stronger. Tensile failure in the glass and glass ceramic takes places via surface flaws, and thus tensile strength is an extrinsic, as opposed to intrinsic property.

  17. IMPROVED BAR IMPACT TESTS USING A PHOTONIC DOPPLER VELOCIMETER

    SciTech Connect

    Bless, S. J.; Tolman, J.; Levinson, S.; Nguyen, J.

    2009-12-28

    Bar impact tests, using the techniques described elsewhere in this symposium, were used to measure compressive and tensile strengths of borosilicate glass, soda lime glass, and a glass ceramic. The glass ceramic was 25% crystalline spinel, furnished by Corning Inc. There are two measures of compressive strength: the peak stress that can be transmitted in unconfined compression, and the 'steady state' strength. For borosilicate glass and soda lime glass, these values were similar, being about 1.8 and 1.5 GPa, respectively. The glass ceramic (25% spinel) was almost 50% stronger. Tensile failure in the glass and glass ceramic takes places via surface flaws, and thus tensile strength is an extrinsic, as opposed to intrinsic property.

  18. Gap Formations Along Specimen-Bar Interfaces in Numerical Simulations of SHPB Tests on Elastic Materials Soft in Shear

    NASA Astrophysics Data System (ADS)

    Raftenberg, Martin N.; Scheidler, Mike

    2009-06-01

    Simulations of split Hopkinson pressure bar (SHPB) tests on elastic materials were performed using LS-DYNA. The specimens were much stiffer in dilatation than in shear. A compressible form of Mooney-Rivlin elasticity was applied with parameters evaluated from ballistic gelatin data. The bars were aluminum. The velocity prescribed on the incident bar increased over a rise time until attaining a steady-state value corresponding to a nominal strain rate of 2500/s. The rise time was varied to observe effects of pulse shaping. All calculations were 2D axisymmetric. A penalty-based contact algorithm was applied at the specimen-bar interfaces. This algorithm introduced a stiffness and a viscosity parameter. In sensitivity studies we varied the radius of the bars, the specimen's mesh, and the two contact parameters. In all calculations with the Mooney-Rivlin model, gaps formed at both specimen-bar interfaces over a wide range of strains. This gap phenomenon appears not to have been previously reported in the SHPB literature. We replaced the Mooney-Rivlin model with linear elasticity in order to explore whether the gaps were associated with material nonlinearity. We fixed Young's modulus at a value much smaller than that of aluminum. For sufficiently large Poisson ratios, we again observed gap formations at both specimen-bar interfaces.

  19. Dynamic photoelasticity with a split Hopkinson pressure bar

    NASA Astrophysics Data System (ADS)

    Morris, David R.; Watson, A. J.

    1991-04-01

    To observe the behaviour of materials subject to impact shock loads, accurate high frequency measurements are vital. The measurement of ultra short pulses (less than 50 microseconds) can be carried out by means of electrical resistance strain guages (ERSGs) . The ERSG's also pick up electromagnetic interference signals. Dynamic photoelasticity was used as a check for the ERSG records. Dynamic photoelastic tests were carried out using a Barr and Stroud CP5 high speed rotating mirror camera. The timing of the event and illumination was critical. Important confirmatory results were obtained by this technique.

  20. 49 CFR 195.304 - Test pressure.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 3 2012-10-01 2012-10-01 false Test pressure. 195.304 Section 195.304... PIPELINE Pressure Testing § 195.304 Test pressure. The test pressure for each pressure test conducted under... continuous hours at a pressure equal to 125 percent, or more, of the maximum operating pressure and, in...

  1. 49 CFR 195.304 - Test pressure.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 3 2014-10-01 2014-10-01 false Test pressure. 195.304 Section 195.304... PIPELINE Pressure Testing § 195.304 Test pressure. The test pressure for each pressure test conducted under... continuous hours at a pressure equal to 125 percent, or more, of the maximum operating pressure and, in...

  2. 49 CFR 195.304 - Test pressure.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 3 2010-10-01 2010-10-01 false Test pressure. 195.304 Section 195.304... PIPELINE Pressure Testing § 195.304 Test pressure. The test pressure for each pressure test conducted under... continuous hours at a pressure equal to 125 percent, or more, of the maximum operating pressure and, in...

  3. 49 CFR 195.304 - Test pressure.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 3 2011-10-01 2011-10-01 false Test pressure. 195.304 Section 195.304... PIPELINE Pressure Testing § 195.304 Test pressure. The test pressure for each pressure test conducted under... continuous hours at a pressure equal to 125 percent, or more, of the maximum operating pressure and, in...

  4. Constant strain rate compression of bovine cortical bone on the Split-Hopkinson Pressure Bar.

    PubMed

    Bekker, A; Cloete, T J; Chinsamy-Turan, A; Nurick, G N; Kok, S

    2015-01-01

    Cortical bone is a visco-elastic material which implies that strain rate will affect its response. Although the Split-Hopkinson Pressure Bar is an accepted technique for determining the dynamic compressive properties of cortical bone it has been shown that the strain rate of compression does not remain constant throughout the duration of a classical experiment with a uniform striker. This raises concerns as to the measurement of smeared responses. This paper presents a shaped striker technique whereby the incident pulse can be shaped to attain a constant strain rate experiment for bovine bone. Shaped strikers offer benefits such as re-usability and increased test repeatability. A comparison of the stress-strain-strain rate responses attained through classical and constant strain rate experiments shows that the shape of the stress-strain curves from conventional experiments is adversely affected in the portion where the strain rate varies. The dynamic response corridors for the two tests are similar, however the ultimate properties are affected. It is concluded that the strain rate history should be presented with dynamic stress-strain responses since the instantaneous strain rate is a likely contributor to potential constitutive models. PMID:25492009

  5. A modified Hopkinson pressure bar experiment to evaluate a damped piezoresistive MEMS accelerometer.

    SciTech Connect

    Frew, Danny Joe; Duong, Henry

    2009-03-01

    We conducted a series of modified Hopkinson pressure bar (HPB) experiments to evaluate a new, damped, high-shock accelerometer that has recently been developed by PCB Piezotronics Inc. Pulse shapers were used to create a long duration, non-dispersive stress pulse in an aluminum bar that interacted with a tungsten disk at the end of the incident bar. We measured stress at the aluminum bar-disk interface with a quartz gage and measured acceleration at the free-end of the disk with an Endevco brand 7270A and the new PCB 3991 accelerometers. The rise-time of the incident stress pulse in the aluminum bar was long enough and the disk length short enough so that the response of the disk can be approximated closely as rigid-body motion; an experimentally verified analytical model has been shown previously to support this assumption. Since the cross-sectional area and mass of the disk were known, we calculated acceleration of the rigid-disk from the quartz-gage force measurement and Newton's Second Law of Motion. Comparisons of accelerations calculated from the quartz-gage data and measured acceleration data show excellent agreement for acceleration pulses with the PCB accelerometer for peak amplitudes between 4,000 and 40,000 Gs , rise times as short as 40 microsec, and pulse durations between 150 and 320 microsec.

  6. Submarine rescue decompression procedure from hyperbaric exposures up to 6 bar of absolute pressure in man: effects on bubble formation and pulmonary function.

    PubMed

    Blatteau, Jean-Eric; Hugon, Julien; Castagna, Olivier; Meckler, Cédric; Vallée, Nicolas; Jammes, Yves; Hugon, Michel; Risberg, Jan; Pény, Christophe

    2013-01-01

    Recent advances in submarine rescue systems have allowed a transfer under pressure of crew members being rescued from a disabled submarine. The choice of a safe decompression procedure for pressurised rescuees has been previously discussed, but no schedule has been validated when the internal submarine pressure is significantly increased i.e. exceeding 2.8 bar absolute pressure. This study tested a saturation decompression procedure from hyperbaric exposures up to 6 bar, the maximum operating pressure of the NATO submarine rescue system. The objective was to investigate the incidence of decompression sickness (DCS) and clinical and spirometric indices of pulmonary oxygen toxicity. Two groups were exposed to a Nitrogen-Oxygen atmosphere (pO2 = 0.5 bar) at either 5 bar (N = 14) or 6 bar (N = 12) for 12 h followed by 56 h 40 min resp. 60 h of decompression. When chamber pressure reached 2.5 bar, the subjects breathed oxygen intermittently, otherwise compressed air. Repeated clinical examinations, ultrasound monitoring of venous gas embolism and spirometry were performed during decompression. During exposures to 5 bar, 3 subjects had minor subjective symptoms i.e. sensation of joint discomfort, regressing spontaneously, and after surfacing 2 subjects also experienced joint discomfort disappearing without treatment. Only 3 subjects had detectable intravascular bubbles during decompression (low grades). No bubbles were detected after surfacing. About 40% of subjects felt chest tightness when inspiring deeply during the initial phase of decompression. Precordial burning sensations were reported during oxygen periods. During decompression, vital capacity decreased by about 8% and forced expiratory flow rates decreased significantly. After surfacing, changes in the peripheral airways were still noticed; Lung Diffusion for carbon monoxide was slightly reduced by 1% while vital capacity was normalized. The procedure did not result in serious symptoms of DCS or

  7. Submarine Rescue Decompression Procedure from Hyperbaric Exposures up to 6 Bar of Absolute Pressure in Man: Effects on Bubble Formation and Pulmonary Function

    PubMed Central

    Blatteau, Jean-Eric; Hugon, Julien; Castagna, Olivier; Meckler, Cédric; Vallée, Nicolas; Jammes, Yves; Hugon, Michel; Risberg, Jan; Pény, Christophe

    2013-01-01

    Recent advances in submarine rescue systems have allowed a transfer under pressure of crew members being rescued from a disabled submarine. The choice of a safe decompression procedure for pressurised rescuees has been previously discussed, but no schedule has been validated when the internal submarine pressure is significantly increased i.e. exceeding 2.8 bar absolute pressure. This study tested a saturation decompression procedure from hyperbaric exposures up to 6 bar, the maximum operating pressure of the NATO submarine rescue system. The objective was to investigate the incidence of decompression sickness (DCS) and clinical and spirometric indices of pulmonary oxygen toxicity. Two groups were exposed to a Nitrogen-Oxygen atmosphere (pO2 = 0.5 bar) at either 5 bar (N = 14) or 6 bar (N = 12) for 12 h followed by 56 h 40 min resp. 60 h of decompression. When chamber pressure reached 2.5 bar, the subjects breathed oxygen intermittently, otherwise compressed air. Repeated clinical examinations, ultrasound monitoring of venous gas embolism and spirometry were performed during decompression. During exposures to 5 bar, 3 subjects had minor subjective symptoms i.e. sensation of joint discomfort, regressing spontaneously, and after surfacing 2 subjects also experienced joint discomfort disappearing without treatment. Only 3 subjects had detectable intravascular bubbles during decompression (low grades). No bubbles were detected after surfacing. About 40% of subjects felt chest tightness when inspiring deeply during the initial phase of decompression. Precordial burning sensations were reported during oxygen periods. During decompression, vital capacity decreased by about 8% and forced expiratory flow rates decreased significantly. After surfacing, changes in the peripheral airways were still noticed; Lung Diffusion for carbon monoxide was slightly reduced by 1% while vital capacity was normalized. The procedure did not result in serious symptoms of DCS or

  8. Hydrogen no-vent testing in a 5 cubic foot (142 liter) tank using spray nozzle and spray bar liquid injection

    NASA Technical Reports Server (NTRS)

    Moran, Matthew E.; Nyland, Ted W.

    1992-01-01

    A total of 38 hydrogen no-vent fill tests were performed in this test series using various size spray nozzles and a spray bar with different hole sizes in a 5 cubic foot receiver tank. Fill levels of 90 percent by volume or greater were achieved in 26 of the tests while maintaining a receiver tank pressure below 30 psia. Spray nozzles were mounted at the top of the tank, whereas, the spray bar was centered in the tank axially. The spray nozzle no-vent fills demonstrated tank pressure and temperature responses comparable to previous test series. Receiver tank pressure responses for the spray bar configuration were similar to the spray nozzle tests with the pressure initially rising rapidly, then leveling off as vapor condenses onto the discharging liquid streams, and finally ramping up near the end of the test due to ullage compression. Both liquid injection techniques tested were capable of filling the receiver tank to 90 percent under variable test conditions. Comparisons between the spray nozzle and spray bar configurations for well matched test conditions indicate the spray nozzle injection technique is more effective in minimizing the receiving tank pressure throughout a no-vent fill compared to the spray bar under normal gravity conditions.

  9. Hydrogen no-vent fill testing in a 5 cubic foot (142 liter) tank using spray nozzle and spray bar liquid injection

    NASA Technical Reports Server (NTRS)

    Moran, Matthew E.; Nyland, Ted W.

    1992-01-01

    A total of 38 hydrogen no-vent fill tests were performed in this test series using various size spray nozzles and a spray bar with different hole sizes in a 5 cubic foot receiver tank. Fill levels of 90 percent by volume or greater were achieved in 26 of the tests while maintaining a receiver tank pressure below 30 psia. Spray nozzles were mounted at the top of the tank, whereas, the spray bar was centered in the tank axially. The spray nozzle no-vent fills demonstrated tank pressure and temperature responses comparable to previous test series. Receiver tank pressure responses for the spray bar configuration were similar to the spray nozzle tests with the pressure initially rising rapidly, then leveling off as vapor condenses onto the discharging liquid streams, and finally ramping up near the end of the test due to ullage compression. Both liquid injection techniques tested were capable of filling the receiver tank to 90 percent under variable test conditions. Comparisons between the spray nozzle and spray bar configurations for well matched test conditions indicate the spray nozzle injection technique is more effective in minimizing the receiving tank pressure throughout a no-vent fill compared to the spray bar under normal gravity conditions.

  10. Transient Pressure Test Article Test Program

    NASA Technical Reports Server (NTRS)

    Vibbart, Charles M.

    1989-01-01

    The Transient Pressure Test Article (TPTA) test program is being conducted at a new test facility located in the East Test Area at the National Aeronautics and Space Administration's (NASA's) Marshall Space Flight Center (MSFC) in Huntsville, Alabama. This facility, along with the special test equipment (STE) required for facility support, was constructed specifically to test and verify the sealing capability of the Redesigned Solid Rocket Motor (RSRM) field, igniter, and nozzle joints. The test article consists of full scale RSRM hardware loaded with inert propellant and assembled in a short stack configuration. The TPTA is pressurized by igniting a propellant cartridge capable of inducing a pressure rise rate which stimulates the ignition transient that occurs during launch. Dynamic loads are applied during the pressure cycle to simulate external tank attach (ETA) strut loads present on the ETA ring. Sealing ability of the redesigned joints is evaluated under joint movement conditions produced by these combined loads since joint sealing ability depends on seal resilience velocity being greater than gap opening velocity. Also, maximum flight dynamic loads are applied to the test article which is either pressurized to 600 psia using gaseous nitrogen (GN2) or applied to the test article as the pressure decays inside the test article on the down cycle after the ignition transient cycle. This new test facility is examined with respect to its capabilities. In addition, both the topic of test effectiveness versus space vehicle flight performance and new aerospace test techniques, as well as a comparison between the old SRM design and the RSRM are presented.

  11. Insertion device for pressure testing

    NASA Technical Reports Server (NTRS)

    Howland, B. T.; Maurin, A. L.

    1969-01-01

    Test device which introduces either pressure or vacuum into a test pipe or tube, is insertable into the tested item where it secures itself into position and requires no external support. The unit has an operating range from zero to 25,000 psig and to any vacuum level that available equipment can reach.

  12. High temperature and pressure electrochemical test station

    NASA Astrophysics Data System (ADS)

    Chatzichristodoulou, C.; Allebrod, F.; Mogensen, M.

    2013-05-01

    An electrochemical test station capable of operating at pressures up to 100 bars and temperatures up to 400 °C has been established. It enables control of the partial pressures and mass flow of O2, N2, H2, CO2, and H2O in a single or dual environment arrangement, measurements with highly corrosive media, as well as localized sampling of gas evolved at the electrodes for gas analysis. A number of safety and engineering design challenges have been addressed. Furthermore, we present a series of electrochemical cell holders that have been constructed in order to accommodate different types of cells and facilitate different types of electrochemical measurements. Selected examples of materials and electrochemical cells examined in the test station are provided, ranging from the evaluation of the ionic conductivity of liquid electrolytic solutions immobilized in mesoporous ceramic structures, to the electrochemical characterization of high temperature and pressure alkaline electrolysis cells and the use of pseudo-reference electrodes for the separation of each electrode contribution. A future perspective of various electrochemical processes and devices that can be developed with the use of the established test station is provided.

  13. High temperature and pressure electrochemical test station.

    PubMed

    Chatzichristodoulou, C; Allebrod, F; Mogensen, M

    2013-05-01

    An electrochemical test station capable of operating at pressures up to 100 bars and temperatures up to 400 °C has been established. It enables control of the partial pressures and mass flow of O2, N2, H2, CO2, and H2O in a single or dual environment arrangement, measurements with highly corrosive media, as well as localized sampling of gas evolved at the electrodes for gas analysis. A number of safety and engineering design challenges have been addressed. Furthermore, we present a series of electrochemical cell holders that have been constructed in order to accommodate different types of cells and facilitate different types of electrochemical measurements. Selected examples of materials and electrochemical cells examined in the test station are provided, ranging from the evaluation of the ionic conductivity of liquid electrolytic solutions immobilized in mesoporous ceramic structures, to the electrochemical characterization of high temperature and pressure alkaline electrolysis cells and the use of pseudo-reference electrodes for the separation of each electrode contribution. A future perspective of various electrochemical processes and devices that can be developed with the use of the established test station is provided. PMID:23742566

  14. Liquid Methane Testing With a Large-Scale Spray Bar Thermodynamic Vent System

    NASA Technical Reports Server (NTRS)

    Hastings, L. J.; Bolshinskiy, L. G.; Hedayat, A.; Flachbart, R. H.; Sisco, J. D.; Schnell. A. R.

    2014-01-01

    NASA's Marshall Space Flight Center conducted liquid methane testing in November 2006 using the multipurpose hydrogen test bed outfitted with a spray bar thermodynamic vent system (TVS). The basic objective was to identify any unusual or unique thermodynamic characteristics associated with densified methane that should be considered in the design of space-based TVSs. Thirteen days of testing were performed with total tank heat loads ranging from 720 to 420 W at a fill level of approximately 90%. It was noted that as the fluid passed through the Joule-Thompson expansion, thermodynamic conditions consistent with the pervasive presence of metastability were indicated. This Technical Publication describes conditions that correspond with metastability and its detrimental effects on TVS performance. The observed conditions were primarily functions of methane densification and helium pressurization; therefore, assurance must be provided that metastable conditions have been circumvented in future applications of thermodynamic venting to in-space methane storage.

  15. Testing of an actively damped boring bar featuring structurally integrated PZT stack actuators

    SciTech Connect

    Redmond, J.; Barney, P.

    1998-06-01

    This paper summarizes the results of cutting tests performed using an actively damped boring bar to minimize chatter in metal cutting. A commercially available 2 inch diameter boring bar was modified to incorporate PZT stack actuators for controlling tool bending vibrations encountered during metal removal. The extensional motion of the actuators induce bending moments in the host structure through a two-point preloaded mounting scheme. Cutting tests performed at various speeds and depths of cuts on a hardened steel workpiece illustrate the bar`s effectiveness toward eliminating chatter vibrations and improving workpiece surface finish.

  16. Application of the Split Hopkinson Resonant Bar Test for Seismic Property Characterization of Hydrate-bearing Sand Undergoing Water Saturation

    SciTech Connect

    Nakagawa, S.; Kneafsey, T.J.

    2011-05-03

    Conventional resonant bar tests allow the measurement of seismic properties of rocks and sediments at low frequencies (several kilohertz). However, the tests require a long, slender sample which is often difficult to obtain from the deep subsurface and weak and fractured formations. We present an alternative low-frequency measurement technique to the conventional resonant bar tests. This technique involves a jacketed core sample placed between a pair of long, metal extension rods with attached seismic source and receiver—the same geometry as the split Hopkinson pressure bar test for large-strain, dynamic impact experiments. Because of the added length and mass to the sample, the resonance frequency of the entire system can be lowered significantly, compared to the sample alone. The proposed “Split Hopkinson Resonant Bar (SHRB)” test is applied in two steps. In the first step, extension and torsion-mode resonance frequencies and attenuation of the system are measured. Then, numerical inversions for the compressional and shear wave velocities and attenuation are performed. We initially applied the SHRB test to synthetic materials (plastics) for testing its accuracy, then used it for measuring the seismic velocities and attenuation of a rock core containing supercritical CO{sub 2}, and a sediment core while methane hydrate formed in the pore space.

  17. 49 CFR 195.304 - Test pressure.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 3 2013-10-01 2013-10-01 false Test pressure. 195.304 Section 195.304... PIPELINE Pressure Testing § 195.304 Test pressure. The test pressure for each pressure test conducted under... case of a pipeline that is not visually inspected for leakage during the test, for at least...

  18. Testing of a Spray-Bar Zero Gravity Cryogenic Vent System for Upper Stages

    NASA Technical Reports Server (NTRS)

    Lak, Tibor; Flachbart, Robin; Nguyen, Han; Martin, James

    1999-01-01

    The capability to vent in zero gravity without resettling is a fundamental technology need that involves practically all uses of subcritical cryogenics in space. Venting without resettling would extend cryogenic orbital transfer vehicle capabilities. However, the lack of definition regarding liquid/ullage orientation coupled with the somewhat random nature of the thermal stratification and resulting pressure rise rates, lead to significant technical challenges. Typically a zero gravity vent concept, termed a thermodynamic vent system (TVS), consists of a tank mixer to destratify the propellant, combined with a Joule- Thomson (J-T) valve to extract then-nal energy from the propellant. In a cooperative effort, Marshall Space Flight Center's (MSFC's) Multipurpose Hydrogen Test Bed (N4HTB) was used to test a unique "spray bar" TVS system developed by Boeing. A schematic of this system is included in Figure 1. The system consists of a recirculation pump, a parallel flow concentric tube, heat exchanger, and a spray bar positioned close to the longitudinal axis of the tank. In the mixing mode, the recirculation pump withdraws liquid from the tank and sprays it radially into the tank liquid, ullage, and exposed tank surfaces. When energy extraction is required, a small portion of the recirculated liquid is passed sequentially through the J-T expansion valve, the spray bar heat exchanger element, and is vented overboard. The vented vapor cools the circulated bulk fluid, thereby removing thermal energy and reducing tank pressure. Figure 2 is a plot of ullage pressure (P4) and liquid vapor pressure (PSAI) versus time. The pump operates alone, cycling on and off, to destratify the tank liquid and ullage until the liquid vapor pressure reaches the lower set point. At that point, the J-T valve begins to cycle on and off with the pump. Thus, for short duration missions, only the mixer may operate, thus minimizing or even eliminating boil-off losses. The primary advantage of the

  19. Split Hopkinson Resonant Bar Test for Sonic-Frequency Acoustic Velocity and Attenuation Measurements of Small, Isotropic Geologic Samples

    SciTech Connect

    Nakagawa, S.

    2011-04-01

    Mechanical properties (seismic velocities and attenuation) of geological materials are often frequency dependent, which necessitates measurements of the properties at frequencies relevant to a problem at hand. Conventional acoustic resonant bar tests allow measuring seismic properties of rocks and sediments at sonic frequencies (several kilohertz) that are close to the frequencies employed for geophysical exploration of oil and gas resources. However, the tests require a long, slender sample, which is often difficult to obtain from the deep subsurface or from weak and fractured geological formations. In this paper, an alternative measurement technique to conventional resonant bar tests is presented. This technique uses only a small, jacketed rock or sediment core sample mediating a pair of long, metal extension bars with attached seismic source and receiver - the same geometry as the split Hopkinson pressure bar test for large-strain, dynamic impact experiments. Because of the length and mass added to the sample, the resonance frequency of the entire system can be lowered significantly, compared to the sample alone. The experiment can be conducted under elevated confining pressures up to tens of MPa and temperatures above 100 C, and concurrently with x-ray CT imaging. The described Split Hopkinson Resonant Bar (SHRB) test is applied in two steps. First, extension and torsion-mode resonance frequencies and attenuation of the entire system are measured. Next, numerical inversions for the complex Young's and shear moduli of the sample are performed. One particularly important step is the correction of the inverted Young's moduli for the effect of sample-rod interfaces. Examples of the application are given for homogeneous, isotropic polymer samples and a natural rock sample.

  20. High-pressure creep tests

    NASA Technical Reports Server (NTRS)

    Bhattacharyya, S.; Lamoureux, J.; Hales, C.

    1986-01-01

    The automotive Stirling engine, presently being developed by the U.S. Department of Energy and NASA, uses high-pressure hydrogen as a working fluid; its long-term effects on the properties of alloys are relatively unknown. Hence, creep-rupture testing of wrought and cast high-temperature alloys in high-pressure hydrogen is an essential part of the research supporting the development of the Stirling cycle engine. Attention is given to the design, development, and operation of a 20 MPa hydrogen high-temperature multispecimen creep-rupture possessing high sensitivity. This pressure vessel allows for the simultaneous yet independent testing of six specimens. The results from one alloy, XF-818, are presented to illustrate how reported results are derived from the raw test data.

  1. Relationship of Bar Examinations to Performance Tests of Lawyering Skills. Rand Paper Series.

    ERIC Educational Resources Information Center

    Klein, Stephen P.

    The relationship between scores on a typical bar exam and the ability to practice law was investigated with 485 applicants who took the bar exam and a 2-day performance test involving basic oral and written legal tasks. These tasks consisted of simulated cases; each participant functioned as the attorney for the plantiff in one case and as the…

  2. 14 CFR 23.843 - Pressurization tests.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Pressurization tests. 23.843 Section 23.843... Pressurization § 23.843 Pressurization tests. (a) Strength test. The complete pressurized cabin, including doors... in § 23.365(d). (b) Functional tests. The following functional tests must be performed: (1) Tests...

  3. 14 CFR 23.843 - Pressurization tests.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Pressurization tests. 23.843 Section 23.843... Pressurization § 23.843 Pressurization tests. (a) Strength test. The complete pressurized cabin, including doors... in § 23.365(d). (b) Functional tests. The following functional tests must be performed: (1) Tests...

  4. 14 CFR 23.843 - Pressurization tests.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Pressurization tests. 23.843 Section 23.843... Pressurization § 23.843 Pressurization tests. (a) Strength test. The complete pressurized cabin, including doors... in § 23.365(d). (b) Functional tests. The following functional tests must be performed: (1) Tests...

  5. SOL Tests Create Unfair Pressure.

    ERIC Educational Resources Information Center

    Ernst, Katie

    2000-01-01

    A seventh-grader explains why the Virginia Standards of Learning tests unfairly pressure her and her teachers. She wants her free reading time restored and wishes politicians would worry more about students understanding--not just memorizing--facts. She praises teachers who go beyond the SOL. (MLH)

  6. Test Data Analysis of a Spray Bar Zero-Gravity Liquid Hydrogen Vent System for Upper Stages

    NASA Technical Reports Server (NTRS)

    Hedayat, A.; Bailey, J. W.; Hastings, L. J.; Flachbart, R. H.

    2003-01-01

    To support development of a zero-gravity pressure control capability for liquid hydrogen (LH2), a series of thermodynamic venting system (TVS) tests was conducted in 1996 and 1998 using the Marshall Space Flight Center (MSFC) multipurpose hydrogen test bed (MHTB). These tests were performed with ambient heat leaks =20 and 50 W for tank fill levels of 90%, 50%, and 25%. TVS performance testing revealed that the spray bar was highly effective in providing tank pressure control within a 7-kPa band (131-138 Wa), and complete destratification of the liquid and the ullage was achieved with all test conditions. Seven of the MHTB tests were correlated with the TVS performance analytical model. The tests were selected to encompass the range of tank fill levels, ambient heat leaks, operational modes, and ullage pressurants. The TVS model predicted ullage pressure and temperature and bulk liquid saturation pressure and temperature obtained from the TVS model were compared with the test data. During extended self-pressurization periods, following tank lockup, the model predicted faster pressure rise rates than were measured. However, once the system entered the cyclic mixing/venting operational mode, the modeled and measured data were quite similar.

  7. Thermodynamic and related properties of parahydrogen from the triple point to 300 K at pressures to 1000 bar

    NASA Technical Reports Server (NTRS)

    Weber, L. A.

    1975-01-01

    Compressibility measurements and thermodynamic properties data for parahydrogen were extended to higher temperatures and pressures. Results of an experimental program are presented in the form of new pressure, volume and temperature data in the temperature range 23 to 300 K at pressures up to 800 bar. Also given are tables of thermodynamic properties on isobars to 1000 bar including density, internal energy, enthalpy, entropy, specific heats at constant volume and constant pressure, velocity of sound, and surface derivatives. The accuracy of the data is discussed and comparisons are made with previous data.

  8. In-situ TEM on (de)hydrogenation of Pd at 0.5-4.5 bar hydrogen pressure and 20-400°C.

    PubMed

    Yokosawa, Tadahiro; Alan, Tuncay; Pandraud, Gregory; Dam, Bernard; Zandbergen, Henny

    2012-01-01

    We have developed a nanoreactor, sample holder and gas system for in-situ transmission electron microscopy (TEM) of hydrogen storage materials up to at least 4.5 bar. The MEMS-based nanoreactor has a microheater, two electron-transparent windows and a gas inlet and outlet. The holder contains various O-rings to have leak-tight connections with the nanoreactor. The system was tested with the (de)hydrogenation of Pd at pressures up to 4.5 bar. The Pd film consisted of islands being 15 nm thick and 50-500 nm wide. In electron diffraction mode we observed reproducibly a crystal lattice expansion and shrinkage owing to hydrogenation and dehydrogenation, respectively. In selected-area electron diffraction and bright/dark-field modes the (de)hydrogenation of individual Pd particles was followed. Some Pd islands are consistently hydrogenated faster than others. When thermally cycled, thermal hysteresis of about 10-16°C between hydrogen absorption and desorption was observed for hydrogen pressures of 0.5-4.5 bar. Experiments at 0.8 bar and 3.2 bar showed that the (de)hydrogenation temperature is not affected by the electron beam. This result shows that this is a fast method to investigate hydrogen storage materials with information at the nanometer scale. PMID:22088507

  9. An electronic pressure profile display system for aeronautic test facilities

    NASA Technical Reports Server (NTRS)

    Woike, Mark R.

    1990-01-01

    The NASA Lewis Research Center has installed an Electronic Pressure Profile Display system. This system provides for the real-time display of pressure readings on high resolution graphics monitors. The Electronic Pressure Profile Display system will replace manometer banks currently used in aeronautic test facilities. The Electronic Pressure Profile Display system consists of an industrial type Digital Pressure Transmitter (DPT) unit which interfaces with a host computer. The host computer collects the pressure data from the DPT unit, converts it into engineering units, and displays the readings on a high resolution graphics monitor in bar graph format. Software was developed to accomplish the above tasks and also draw facility diagrams as background information on the displays. Data transfer between host computer and DPT unit is done with serial communications. Up to 64 channels are displayed with one second update time. This paper describes the system configuration, its features, and its advantages over existing systems.

  10. An Electronic Pressure Profile Display system for aeronautic test facilities

    NASA Technical Reports Server (NTRS)

    Woike, Mark R.

    1990-01-01

    The NASA Lewis Research Center has installed an Electronic Pressure Profile Display system. This system provides for the real-time display of pressure readings on high resolution graphics monitors. The Electronic Pressure Profile Display system will replace manometer banks currently used in aeronautic test facilities. The Electronic Pressure Profile Display system consists of an industrial type Digital Pressure Transmitter (DPI) unit which interfaces with a host computer. The host computer collects the pressure data from the DPI unit, converts it into engineering units, and displays the readings on a high resolution graphics monitor in bar graph format. Software was developed to accomplish the above tasks and also draw facility diagrams as background information on the displays. Data transfer between host computer and DPT unit is done with serial communications. Up to 64 channels are displayed with one second update time. This paper describes the system configuration, its features, and its advantages over existing systems.

  11. Quasi-CW Laser Diode Bar Life Tests

    NASA Technical Reports Server (NTRS)

    Stephen, Mark A.; Krainak, Michael A.; Dallas, Joseph L.

    1997-01-01

    NASA's Goddard Space Flight Center is developing technology for satellite-based, high peak power, LIDAR transmitters requiring 3-5 years of reliable operation. Semi-conductor laser diodes provide high efficiency pumping of solid state lasers with the promise of long-lived, reliable operation. 100-watt quasi- CW laser diode bars have been baselined for the next generation laser altimeters. Multi-billion shot lifetimes are required. The authors have monitored the performance of several diodes for billions of shots and investigated operational modes for improving diode lifetime.

  12. Report on FY15 Two-Bar Thermal Ratcheting Test Results

    SciTech Connect

    Wang, Yanli; Jetter, Robert I; Baird, Seth T; Pu, Chao; Sham, Sam

    2015-06-22

    Alloy 617 is a reference structural material for very high temperature components of advanced-gas cooled reactors with outlet temperatures in the range of . In order for designers to be able to use Alloy 617 for these high temperature components, Alloy 617 has to be approved for use in Section III (the nuclear section) of the American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel Code. A plan has been developed to submit a draft code for Alloy 617 to ASME Section III by 2015. However, the current rules in Subsection NH* for the evaluation of strain limits and creep-fatigue damage using simplified methods based on elastic analysis have been deemed inappropriate for Alloy 617 at temperatures above . The rationale for this exclusion is that at higher temperatures it is not feasible to decouple plasticity and creep deformation, which is the basis for the current simplified rules. This temperature, , is well below the temperature range of interest for this material in High Temperature Gas Cooled Reactor (HTGR) applications. The only current alternative is, thus, a full inelastic analysis which requires sophisticated material models which have been formulated but not yet verified. To address this issue, proposed code rules have been developed which are based on the use of elastic-perfectly plastic (EPP) analysis methods and which are expected to be applicable to very high temperatures. These newly proposed rules also address a long-term objective to provide an option for more simple, comprehensive and easily applied rules than the current so called simplified rules These two-bar tests discussed herein are part of an ongoing series of tests with cyclic loading at high temperatures using specimens representing key features of potential component designs. The initial focus of the two-bar ratcheting test program, to verify the procedure for evaluation of strain limits for Alloy 617 at very high temperatures, has been expanded to respond to guidance from

  13. Effect of the application of a metatarsal bar on pressure in the metatarsal bones of the foot

    PubMed Central

    Yoon, Se Won

    2015-01-01

    [Purpose] The aim of this study was to determine the effect of application of a metatarsal bar on the pressure in the metatarsal bones of the foot using a foot analysis system (pressure on the forefoot, midfoot, and rearfoot). [Subjects and Methods] Forty female university students in their twenties were selected for this study, and an experiment was conducted with them as the subjects, before and after application of a metatarsal bar. The static foot regions were divided into the forefoot, midfoot, and rearfoot, and then the maximum, average, and low pressures exerted at each region were measured, along with the static foot pressure distribution ratio. 1) Static foot pressure: The tips of both feet were aligned to match the vertical and horizontal lines of the foot pressure measuring plate. The subjects were told to look toward the front and not to wear shoes. 2) Distribution ratio: The distribution ratio was measured in four regions (front, back, left, and right) using the same method as used for static foot pressure measurement. [Results] The results of this study showed that the maximum, average, and minimum static pressures in the forefoot were significantly decreased. The minimum static pressure in the midfoot was significantly increased, and the pressure in the other parts was significantly decreased. The maximum and average static pressures in the rearfoot were also significantly decreased. [Conclusion] As reduction of foot pressure with a metatarsal bar results in lowering of the arch and an increased contact surface, the foot pressure was dispersed. These results suggest that wearing shoes with a bar that can decrease the foot pressure is therapeutically helpful for patients with a diabetic foot lesion or rheumatoid arthritis. PMID:26311941

  14. Testing for Controlled Rapid Pressurization

    DOE Data Explorer

    Steven Knudsen

    2014-09-03

    Borehole W1 is a NQ core hole drilled at our test site in Socorro. The rock is rhyolite. Borehole W1 which was used to test gas-gas explosive mixtures is 55 feet deep with casing (pinkish in the drawing) set to 35 feet. The model is a representation of the borehole and the holes we cored around the central borehole after the test. The brown colored core holes showed dye when we filled W1 with water and slightly pressurized it. This indicates there was some path between W1 and the colored core hole. The core holes are shown to their TD in the drawing. The green plane is a fracture plane which we believe is the result of the explosions of the gas mixture in W1. Data resource is a 2D .pdf Solid Works Drawing of borehole w-1

  15. 49 CFR 230.35 - Pressure testing.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 4 2012-10-01 2012-10-01 false Pressure testing. 230.35 Section 230.35... Pressure Testing of Boilers § 230.35 Pressure testing. The temperature of the steam locomotive boiler shall be raised to at least 70 deg. F any time hydrostatic pressure is applied to the boiler....

  16. 33 CFR 159.109 - Pressure test.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 2 2014-07-01 2014-07-01 false Pressure test. 159.109 Section...) POLLUTION MARINE SANITATION DEVICES Design, Construction, and Testing § 159.109 Pressure test. Any sewage retention tank that is designed to operate under pressure must be pressurized hydrostatically at a...

  17. 49 CFR 230.35 - Pressure testing.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 4 2011-10-01 2011-10-01 false Pressure testing. 230.35 Section 230.35... Pressure Testing of Boilers § 230.35 Pressure testing. The temperature of the steam locomotive boiler shall be raised to at least 70 deg. F any time hydrostatic pressure is applied to the boiler....

  18. 33 CFR 159.109 - Pressure test.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 2 2013-07-01 2013-07-01 false Pressure test. 159.109 Section...) POLLUTION MARINE SANITATION DEVICES Design, Construction, and Testing § 159.109 Pressure test. Any sewage retention tank that is designed to operate under pressure must be pressurized hydrostatically at a...

  19. 49 CFR 230.35 - Pressure testing.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 4 2013-10-01 2013-10-01 false Pressure testing. 230.35 Section 230.35... Pressure Testing of Boilers § 230.35 Pressure testing. The temperature of the steam locomotive boiler shall be raised to at least 70 deg. F any time hydrostatic pressure is applied to the boiler....

  20. 49 CFR 230.35 - Pressure testing.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 4 2014-10-01 2014-10-01 false Pressure testing. 230.35 Section 230.35... Pressure Testing of Boilers § 230.35 Pressure testing. The temperature of the steam locomotive boiler shall be raised to at least 70 deg. F any time hydrostatic pressure is applied to the boiler....

  1. 33 CFR 159.109 - Pressure test.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 2 2012-07-01 2012-07-01 false Pressure test. 159.109 Section...) POLLUTION MARINE SANITATION DEVICES Design, Construction, and Testing § 159.109 Pressure test. Any sewage retention tank that is designed to operate under pressure must be pressurized hydrostatically at a...

  2. 49 CFR 230.35 - Pressure testing.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Pressure testing. 230.35 Section 230.35... Pressure Testing of Boilers § 230.35 Pressure testing. The temperature of the steam locomotive boiler shall be raised to at least 70 deg. F any time hydrostatic pressure is applied to the boiler....

  3. 33 CFR 159.109 - Pressure test.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Pressure test. 159.109 Section...) POLLUTION MARINE SANITATION DEVICES Design, Construction, and Testing § 159.109 Pressure test. Any sewage retention tank that is designed to operate under pressure must be pressurized hydrostatically at a...

  4. Effect of confining pressure due to external jacket of steel plate or shape memory alloy wire on bond behavior between concrete and steel reinforcing bars.

    PubMed

    Choi, Eunsoo; Kim, Dongkyun; Park, Kyoungsoo

    2014-12-01

    For external jackets of reinforced concrete columns, shape memory alloy (SMA) wires are easy to install, and they provide active and passive confining pressure; steel plates, on the other hand, only provide passive confining pressure, and their installation on concrete is not convenient because of the requirement of a special device. To investigate how SMA wires distinctly impact bond behavior compared with steel plates, this study conducted push-out bond tests of steel reinforcing bars embedded in concrete confined by SMA wires or steel plates. For this purpose, concrete cylinders were prepared with dimensions of 100 mm x 200 mm, and D-22 reinforcing bars were embedded at the center of the concrete cylinders. External jackets of 1.0 mm and 1.5 mm thickness steel plates were used to wrap the concrete cylinders. Additionally, NiTiNb SMA wire with a diameter of 1.0 mm was wound around the concrete cylinders. Slip of the reinforcing bars due to pushing force was measured by using a displacement transducer, while the circumferential deformation of specimens was obtained by using an extensometer. The circumferential deformation was used to calculate the circumferential strains of the specimens. This study assessed the radial confining pressure due to the external jackets on the reinforcing bars at bond strength from bond stress-slip curves and bond stress-circumferential strain curves. Then, the effects of the radial confining pressure on the bond behavior of concrete are investigated, and an equation is suggested to estimate bond strength using the radial confining pressure. Finally, this study focused on how active confining pressure due to recovery stress of the SMA wires influences bond behavior. PMID:25971115

  5. A regularized model for impact in explicit dynamics applied to the split Hopkinson pressure bar

    NASA Astrophysics Data System (ADS)

    Otto, Peter; De Lorenzis, Laura; Unger, Jörg F.

    2016-07-01

    In the numerical simulation of impact phenomena, artificial oscillations can occur due to an instantaneous change of velocity in the contact area. In this paper, a nonlinear penalty regularization is used to avoid these oscillations. A particular focus is the investigation of higher order methods in space and time to increase the computational efficiency. The spatial discretization is realized by higher order spectral element methods that are characterized by a diagonal mass matrix. The time integration scheme is based on half-explicit Runge-Kutta scheme of fourth order. For the conditionally stable scheme, the critical time step is influenced by the penalty regularization. A framework is presented to adjust the penalty stiffness and the time step for a specific mesh to avoid oscillations. The methods presented in this paper are applied to 1D-simulations of a split Hopkinson pressure bar, which is commonly used for the investigation of materials under dynamic loading.

  6. Thermodynamic and related properties of oxygen from the triple point to 300 K at pressures to 1000 bar

    NASA Technical Reports Server (NTRS)

    Weber, L. A.

    1977-01-01

    The results of an experimental program are presented in the form of PVT data in the temperature range 58 to 300 K at pressures up to 800 bar. Tables of the derived thermodynamic properties on isobars to 1000 bar are given, including density, internal energy, enthalpy, entropy, specific heats at constant volume and constant pressure, velocity of sound, and the surface derivatives (delta P/delta T) sub rho and (delta P/delta Rho) sub T. Auxiliary tables in engineering units are also given. The accuracy of the data is discussed and comparisons are made with previous data.

  7. A test of the association of infrared activity with bars. [Intragalactic dynamics

    SciTech Connect

    Pompea, S.M.; Rieke, G.H. )

    1990-06-01

    The hypothesis that high FIR luminosities in noninteracting galaxies are dependent on material fed into their nuclei or into circumnuclear rings along bars can be tested by NIR imaging. A sample of 22 galaxies was selected from the Revised Shapley-Ames Catalog, that have FIR luminosities greater than 10 to the 10th lunar luminosities and hot colors between 60 and 100 microns, indicative of possible nuclear starbursts, but are not interacting or classified as Seyfert galaxies. Fifteen galaxies of the sample of 16 that are not clearly barred from optical data and are isolated were imaged at 1.6 micron and 2.2 microns. In an evaluation of the IR images, at least eight of these galaxies do not appear to have bars. Strong bars therefore do not appear to be an absolute requirement for high IR luminosity. 21 refs.

  8. A test of the association of infrared activity with bars. [intragalactic dynamics

    NASA Technical Reports Server (NTRS)

    Pompea, Stephen M.; Rieke, G. H.

    1990-01-01

    The hypothesis that high FIR luminosities in noninteracting galaxies are dependent on material fed into their nuclei or into circumnuclear rings along bars can be tested by NIR imaging. A sample of 22 galaxies was selected from the Revised Shapley-Ames Catalog, that have FIR luminosities greater than 10 to the 10th lunar luminosities and hot colors between 60 and 100 microns, indicative of possible nuclear starbursts, but are not interacting or classified as Seyfert galaxies. Fifteen galaxies of the sample of 16 that are not clearly barred from optical data and are isolated were imaged at 1.6 micron and 2.2 microns. In an evaluation of the IR images, at least eight of these galaxies do not appear to have bars. Strong bars therefore do not appear to be an absolute requirement for high IR luminosity.

  9. Development of a miniature tensile Kolsky bar for dynamic testing of thin films

    NASA Astrophysics Data System (ADS)

    Paul, Jastin V.

    Mechanical properties such as yield stress and ultimate strength are most commonly obtained under quasi-static (strain rate of 10--4 s--1) loading conditions Materials such as metals, ceramics, and polymers may exhibit significant changes in mechanical response when subjected to high strain rate (102 --105 per second) conditions. The loading rate or strain rate can affect the material properties such as elastic modulus, yield strength, work hardening, and ductility. To ensure product quality and reliability under impact conditions, the mechanical responses of materials under dynamic loading conditions must be characterized. A Kolsky bar is a tool that can be used to study the uniaxial compressive constitutive behavior of materials under high strain rates. The goal of this thesis is to develop a miniature Tensile Kolsky bar that can be used to test materials with thickness on the order of 200 micrometers (thin foils). The system consists of a cylindrical launch tube with an internal striker, a rectangular incident bar and a transmitted bar. The specimen is held in pockets that were milled directly into the incident and transmitted bar. The rectangular incident and transmitted bars facilitate specimen and strain gage mounting. The rectangular section also provides a reduced cross sectional bar area compared to a bar of circular cross section with diameter equivalent to the width of the rectangular bar, which increases the system sensitivity. This thesis presents the detailed description of the miniature Kolsky bar device, specimen geometry, diagnostic techniques and different calibration and validation techniques used for developing the system. The Kolsky bar setup was used to test 99.9 percent pure magnesium at two different strain rates (5000 and 10000 per second). Specimens were cut from billets processed via the 4Bc equal channel angular extrusion route and were tested in three different directions: extrusion, longitudinal and transverse. The results from the

  10. Surface Fatigue Tests Of M50NiL Gears And Bars

    NASA Technical Reports Server (NTRS)

    Townsend, Dennis P.; Bamberger, Eric N.

    1994-01-01

    Report presents results of tests of steels for use in gears and bearings of advanced aircraft. Spur-gear endurance tests and rolling-element surface fatigue tests performed on gear and bar specimens of M50NiL steel processed by vacuum induction melting and vacuum arc remelting (VIM-VAR). Compares results of tests with similar tests of specimens of VIM-VAR AISI 9310 steel and of AISI 9310 steel subjected to VAR only.

  11. Simulation of Watts Bar Unit 1 Initial Startup Tests with Continuous Energy Monte Carlo Methods

    SciTech Connect

    Godfrey, Andrew T; Gehin, Jess C; Bekar, Kursat B; Celik, Cihangir

    2014-01-01

    The Consortium for Advanced Simulation of Light Water Reactors* is developing a collection of methods and software products known as VERA, the Virtual Environment for Reactor Applications. One component of the testing and validation plan for VERA is comparison of neutronics results to a set of continuous energy Monte Carlo solutions for a range of pressurized water reactor geometries using the SCALE component KENO-VI developed by Oak Ridge National Laboratory. Recent improvements in data, methods, and parallelism have enabled KENO, previously utilized predominately as a criticality safety code, to demonstrate excellent capability and performance for reactor physics applications. The highly detailed and rigorous KENO solutions provide a reliable nu-meric reference for VERAneutronics and also demonstrate the most accurate predictions achievable by modeling and simulations tools for comparison to operating plant data. This paper demonstrates the performance of KENO-VI for the Watts Bar Unit 1 Cycle 1 zero power physics tests, including reactor criticality, control rod worths, and isothermal temperature coefficients.

  12. Influence of grid bar shape on field cleaner performance - field testing

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A test was conducted to evaluate the influence of grid bar cross sectional shape on cotton stripper field cleaner performance in terms of cleaning efficiency, seed cotton loss, and fiber and yarn quality. Three field cleaner configurations were tested on a cotton stripper harvester operating under f...

  13. The Measurement of Pressure Through Tubes in Pressure Distribution Tests

    NASA Technical Reports Server (NTRS)

    Hemke, Paul E

    1928-01-01

    The tests described in this report were made to determine the error caused by using small tubes to connect orifices on the surface of aircraft to central pressure capsules in making pressure distribution tests. Aluminum tubes of 3/16-inch inside diameter were used to determine this error. Lengths from 20 feet to 226 feet and pressures whose maxima varied from 2 inches to 140 inches of water were used. Single-pressure impulses for which the time of rise of pressure from zero to a maximum varied from 0.25 second to 3 seconds were investigated. The results show that the pressure recorded at the capsule on the far end of the tube lags behind the pressure at the orifice end and experiences also a change in magnitude. For the values used in these tests the time lag and pressure change vary principally with the time of rise of pressure from zero to a maximum and the tube length. Curves are constructed showing the time lag and pressure change. Empirical formulas are also given for computing the time lag. Analysis of pressure distribution tests made on airplanes in flight shows that the recorded pressures are slightly higher than the pressures at the orifice and that the time lag is negligible. The apparent increase in pressure is usually within the experimental error, but in the case of the modern pursuit type of airplane the pressure increase may be 5 per cent. For pressure-distribution tests on airships the analysis shows that the time lag and pressure change may be neglected.

  14. Crack initiation at high loading rates applying the four-point bending split Hopkinson pressure bar technique

    NASA Astrophysics Data System (ADS)

    Henschel, Sebastian; Krüger, Lutz

    2015-09-01

    Dynamic crack initiation with crack-tip loading rates of K˙ ≈ 2.106MPa√ms-1 in a high strength G42CrMoS4 steel was investigated. To this end, a previously developed split Hopkinson pressure bar with four-point bending was utilised. V-notched and pre-cracked Charpy specimens were tested. The detection of dynamic crack initiation was performed by analysing the dynamic force equilibrium between the incident and the transmission bar. Additionally, the signal of a near-field strain gauge and high-speed photography were used to determine the instant of crack initiation. To account for vibrations of the sample, a dynamic analysis of the stress intensity factor was performed. The dynamic and static analyses of the tests produced nearly the same results when a force equilibrium was achieved. Fracture-surface analysis revealed that elongated MnS inclusions strongly affected both the dynamic crack initiation and growth. Blunting of the precrack did not take place when a group of MnS inclusions was located directly at the precrack tip. Due to the direction of the elongated MnS inclusions perpendicular to the direction of crack growth, the crack could be deflected. The comparison with a 42CrMo4 steel without elongated MnS inclusions revealed the detrimental effect in terms of resistance to crack initiation. Taking the loading-rate dependency into consideration, it was shown that there was no pronounced embrittlement due to the high loading rates.

  15. High-strain rate tensile characterization of graphite platelet reinforced vinyl ester based nanocomposites using split-Hopkinson pressure bar

    NASA Astrophysics Data System (ADS)

    Pramanik, Brahmananda

    The dynamic response of exfoliated graphite nanoplatelet (xGnP) reinforced and carboxyl terminated butadiene nitrile (CTBN) toughened vinyl ester based nanocomposites are characterized under both dynamic tensile and compressive loading. Dynamic direct tensile tests are performed applying the reverse impact Split Hopkinson Pressure Bar (SHPB) technique. The specimen geometry for tensile test is parametrically optimized by Finite Element Analysis (FEA) using ANSYS Mechanical APDLRTM. Uniform stress distribution within the specimen gage length has been verified using high-speed digital photography. The on-specimen strain gage installation is substituted by a non-contact Laser Occlusion Expansion Gage (LOEG) technique for infinitesimal dynamic tensile strain measurements. Due to very low transmitted pulse signal, an alternative approach based on incident pulse is applied for obtaining the stress-time history. Indirect tensile tests are also performed combining the conventional SHPB technique with Brazilian disk test method for evaluating cylindrical disk specimens. The cylindrical disk specimen is held snugly in between two concave end fixtures attached to the incident and transmission bars. Indirect tensile stress is estimated from the SHPB pulses, and diametrical transverse tensile strain is measured using LOEG. Failure diagnosis using high-speed digital photography validates the viability of utilizing this indirect test method for characterizing the tensile properties of the candidate vinyl ester based nanocomposite system. Also, quasi-static indirect tensile response agrees with previous investigations conducted using the traditional dog-bone specimen in quasi-static direct tensile tests. Investigation of both quasi-static and dynamic indirect tensile test responses show the strain rate effect on the tensile strength and energy absorbing capacity of the candidate materials. Finally, the conventional compressive SHPB tests are performed. It is observed that both

  16. Network Performance Testing for the BaBar Event Builder

    SciTech Connect

    Pavel, Tomas J

    1998-11-17

    We present an overview of the design of event building in the BABAR Online, based upon TCP/IP and commodity networking technology. BABAR is a high-rate experiment to study CP violation in asymmetric e{sup +}e{sup {minus}} collisions. In order to validate the event-builder design, an extensive program was undertaken to test the TCP performance delivered by various machine types with both ATM OC-3 and Fast Ethernet networks. The buffering characteristics of several candidate switches were examined and found to be generally adequate for our purposes. We highlight the results of this testing and present some of the more significant findings.

  17. 14 CFR 23.843 - Pressurization tests.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ..., windows, canopy, and valves, must be tested as a pressure vessel for the pressure differential specified... the functioning and capacity of the positive and negative pressure differential valves, and of the... system to show proper functioning under each possible condition of pressure, temperature, and...

  18. BaBar superconducting coil: design, construction and test

    SciTech Connect

    Bell, R A; Berndt, M; Burgess, W; Craddock, W; Dormicchi, O; Fabbricatore, P; Farinon, S; Keller, L; Moreschi, P; Musenich, R; O'Connor, T G; Penco, R; Priano, C; Shen, S; Valente, P

    2001-01-26

    The BABAR Detector, located in the PEP-II B-Factory at the Stanford Linear Accelerator Center, includes a large 1.5 Tesla superconducting solenoid, 2.8 m bore and length 3.7 m. The two layer solenoid is wound with an aluminum stabilized conductor which is graded axially to produce a {+-} 3% field uniformity in the tracking region. This paper summarizes the 3 year design, fabrication and testing program of the superconducting solenoid. The work was carried out by an international collaboration between INFN, LLNL and SLAC. The coil was constructed by Ansaldo Energia. Critical current measurements of the superconducting strand, cable and conductor, cool-down, operation with the thermo-siphon cooling, fast and slow discharges, and magnetic forces are discussed in detail.

  19. 33 CFR 159.109 - Pressure test.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 2 2011-07-01 2011-07-01 false Pressure test. 159.109 Section 159.109 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) POLLUTION MARINE SANITATION DEVICES Design, Construction, and Testing § 159.109 Pressure test. Any...

  20. Implementation of viscoelastic Hopkinson bars

    NASA Astrophysics Data System (ADS)

    Curry, R.; Cloete, T.; Govender, R.

    2012-08-01

    Knowledge of the properties of soft, viscoelastic materials at high strain rates are important in furthering our understanding of their role during blast or impact events. Testing these low impedance materials using a metallic split Hopkinson pressure bar setup results in poor signal to noise ratios due to impedance mismatching. These difficulties are overcome by using polymeric Hopkinson bars. Conventional Hopkinson bar analysis cannot be used on the polymeric bars due to the viscoelastic nature of the bar material. Implementing polymeric Hopkinson bars requires characterization of the viscoelastic properties of the material used. In this paper, 30 mm diameter Polymethyl Methacrylate bars are used as Hopkinson pressure bars. This testing technique is applied to polymeric foam called Divinycell H80 and H200. Although there is a large body of of literature containing compressive data, this rarely deals with strain rates above 250s-1 which becomes increasingly important when looking at the design of composite structures where energy absorption during impact events is high on the list of priorities. Testing of polymeric foams at high strain rates allows for the development of better constitutive models.

  1. Pressurized solid oxide fuel cell testing

    SciTech Connect

    Basel, R.A.; Pierre, J.F.

    1995-08-01

    The goals of the SOFC pressurized test program are to obtain cell voltage versus current (VI) performance data as a function of pressure; to evaluate the effects of operating parameters such as temperature, air stoichiometry, and fuel utilization on cell performance, and to demonstrate long term stability of the SOFC materials at elevated pressures.

  2. Rotational reorientation dynamics at high pressures: rhodamine 6G in ethanol from 1 bar to 6 kbar

    SciTech Connect

    Philips, L.A.; Webb, S.P.; Yeh, S.W.; Clark, J.H.

    1985-01-03

    Picosecond, time-resolved fluorescence depolarization spectroscopy has been used to measure the rotational reorientation time (tau/sub or/) of electronically excited rhodamine 6G. When the dependence of tau/sub or/ on solvent viscosity for a series of linear alcohols is compared with that for ethanol as a function of pressure over the range from 1 bar to 6 kbar, substantially different rotational reorientation dynamics are found for identical macroscopic viscosities. 31 references, 2 figures, 2 tables.

  3. Pressure Dependence of the Acid/Base Equilibria of Methyl Orange in Aqueous Solutions to 1000 bars at 20°C

    SciTech Connect

    Suleimenov, Oleg M; Boily, Jean F

    2006-07-31

    The pressure dependence on the acid/base equilibria of methyl orange in aqueous solution was measured at 20°C in the 1-1000 bar range with a newly designed flow-through spectrophotometric cell. Combined chemometric and thermodynamic analyses of uv-vis spectrophotometric data were used to extract the dissociation constants as well as the changes in molar volume and isothermal compressibility of methyl orange as a function of pressure. The results show increasing pressure promotes the deprotonation of the methyl orange, with pK values ranging from 3.505 at 1 bar to 3.445 (0.002) at 1000 bars. Increasing pressure also yields small values of negative changes in the molar volume ranging from –6.9 cm3∙mol-1 at 1 bar to –1.7 cm3∙mol-1 at 1000 bars. The isothermal compressibility of methyl orange in this pressure range was estimated using the 2nd derivative of 2nd and 3rd order polynomial fits to the constants and gave rise to a constant value of –48.4x 10-4 cm3∙mol-1∙bar-1 in the former case, and increasing values from -107×10-4 cm3∙mol-1∙bar-1 at 1 bar to 3.43×10-4 cm3∙mol-1∙bar-1 at 1000 bars in the latter case. Molar absorption coefficients for the protonated and deprotonated species were also shown to be only slightly affected by pressure changes and can be used to accurately predict the absorption spectra of methyl orange as a function of pressure.

  4. Minimum bar size for flexure testing of irradiated SiC/SiC composite

    SciTech Connect

    Youngblood, G.E.; Jones, R.H.

    1998-03-01

    This report covers material presented at the IEA/Jupiter Joint International Workshop on SiC/SiC Composites for Fusion structural Applications held in conjunction with ICFRM-8, Sendai, Japan, Oct. 23-24, 1997. The minimum bar size for 4-point flexure testing of SiC/SiC composite recommended by PNNL for irradiation effects studies is 30 {times} 6 {times} 2 mm{sup 3} with a span-to-depth ratio of 10/1.

  5. Multi-Canister overpack pressure testing

    SciTech Connect

    SMITH, K.E.

    1998-11-03

    The Multi-Canister Overpack (MCO) shield plug closure assembly will be hydrostatically tested at the fabricator's shop to the 150 psig design test requirement in accordance with the ASME Code. Additionally, the MCO shell and collar will be hydrostatically tested at the fabricator's shop to the 450 psig design test requirement. Commercial practice has not required a pressure test of the closure weld after spent fuel is loaded in the containers. Based on this precedent and Code Case N-595-I, the MCO closure weld will not be pressure tested in the field.

  6. Analysis of pressure distortion testing

    NASA Technical Reports Server (NTRS)

    Koch, K. E.; Rees, R. L.

    1976-01-01

    The development of a distortion methodology, method D, was documented, and its application to steady state and unsteady data was demonstrated. Three methodologies based upon DIDENT, a NASA-LeRC distortion methodology based upon the parallel compressor model, were investigated by applying them to a set of steady state data. The best formulation was then applied to an independent data set. The good correlation achieved with this data set showed that method E, one of the above methodologies, is a viable concept. Unsteady data were analyzed by using the method E methodology. This analysis pointed out that the method E sensitivities are functions of pressure defect level as well as corrected speed and pattern.

  7. Effect of pressure and shielding gas on the microstructure of hyperbaric metal cored GMAW welds down to 111 bar

    SciTech Connect

    Jorge, J.C.F.; Santos, V.R. dos

    1995-12-31

    The microstructural evolution of hyperbaric C-Mn weld metals was studied by means of bead-on-plate welds deposit with GMAW process using a commercial metal cored wire. The welding was carried out in the flat position in the range of 51 bar to 111 bar with He+ CO{sub 2} as shielding gas, which CO{sub 2} content varied from 0.1% to 0.8 %. The microstructures were quantitatively analyzed by optical microscopy to evaluate the amount of constituents according to the IIW/IIS terminology. The results showed that all weld metals presented great amounts of acicular ferrite and a stronger influence of pressure on microstructure compared to the influence of the shielding gas.

  8. Lead test assembly irradiation and analysis Watts Bar Nuclear Plant, Tennessee and Hanford Site, Richland, Washington

    SciTech Connect

    1997-07-01

    The U.S. Department of Energy (DOE) needs to confirm the viability of using a commercial light water reactor (CLWR) as a potential source for maintaining the nation`s supply of tritium. The Proposed Action discussed in this environmental assessment is a limited scale confirmatory test that would provide DOE with information needed to assess that option. This document contains the environmental assessment results for the Lead test assembly irradiation and analysis for the Watts Bar Nuclear Plant, Tennessee, and the Hanford Site in Richland, Washington.

  9. Normal-Pressure Tests of Rectangular Plates

    NASA Technical Reports Server (NTRS)

    Ramberg, Walter; Mcpherson, Albert E; Levy, Samuel

    1942-01-01

    Report presents the results of normal-pressure tests made of 56 rectangular plates with clamped edges and of 5 plates with freely supported edges. Pressure was applied and the center deflection and the permanent set at the center were measured. For some of the plates, in addition, strains and contours were measured.

  10. Testing Transgenic Aspen Plants with bar Gene for Herbicide Resistance under Semi-natural Conditions

    PubMed Central

    Lebedev, V. G.; Faskhiev, V. N.; Kovalenko, N. P.; Shestibratov, K. A.; Miroshnikov, A. I.

    2016-01-01

    Obtaining herbicide resistant plants is an important task in the genetic engineering of forest trees. Transgenic European aspen plants (Populus tremula L.) expressing the bar gene for phosphinothricin resistance have been produced using Agrobacterium tumefaciens-mediated transformation. Successful genetic transformation was confirmed by PCR analysis for thirteen lines derived from two elite genotypes. In 2014–2015, six lines were evaluated for resistance to herbicide treatment under semi-natural conditions. All selected transgenic lines were resistant to the herbicide Basta at doses equivalent to 10 l/ha (twofold normal field dosage) whereas the control plants died at 2.5 l/ha. Foliar NH4-N concentrations in transgenic plants did not change after treatment. Extremely low temperatures in the third ten-day period of October 2014 revealed differences in freeze tolerance between the lines obtained from Pt of f2 aspen genotypes. Stable expression of the bar gene after overwintering outdoors was confirmed by RT-PCR. On the basis of the tests, four transgenic aspen lines were selected. The bar gene could be used for retransformation of transgenic forest trees expressing valuable traits, such as increased productivity. PMID:27437143

  11. Hopkinson bar techniques for the intermediate strain rate testing of bovine cortical bone

    PubMed Central

    Cloete, T. J.; Paul, G.; Ismail, E. B.

    2014-01-01

    Detailed knowledge of the dynamic viscoelastic properties of bone is required to understand the mechanisms of macroscopic bone fracture in humans, and other terrestrial mammals, during impact loading events (e.g. falls, vehicle accidents, etc.). While the dynamic response of bone has been studied for several decades, high-quality data remain limited, and it is only within the last decade that techniques for conducting dynamic compression tests on bone at near-constant strain rates have been developed. Furthermore, there appears to be a lack of published bone data in the intermediate strain rate (ISR) range (i.e. 1–100 s−1), which represents a regime in which many dynamic bone fractures occur. In this paper, preliminary results for the dynamic compression of bovine cortical bone in the ISR regime are presented. The results are obtained using two Hopkinson-bar-related techniques, namely the conventional split Hopkinson bar arrangement incorporating a novel cone-in-tube striker design, and the recently developed wedge bar apparatus. The experimental results show a rapid transition in the strain rate sensitive behaviour of bovine cortical bone in the ISR range. Finally, a new viscoelastic model is proposed that captures the observed transition behaviour. PMID:24711493

  12. Pressure reversal study through tensile tests

    SciTech Connect

    Swinson, W.F.; Battiste, R.L.; Wright, A.L.; Yahr, G.T.; Robertson, J.P.

    1997-12-31

    This paper is a summary of the results from a study of the variables related to pressure reversal and was sponsored by the US Department of Transportation, Office of Pipeline Safety. The circumferential pipe stress, which is the most significant variable in pressure reversal, was examined by using tensile specimens and then relating the results to pressurized pipe. A model is proposed that gives some insight into how pressure reversal can be minimized when a section of pipe is being hydrotested. Twenty tensile specimens from X-42 electric resistance welded (ERW) pipe and twenty specimens from X-52 ERW pipe were tested. Each specimen had a machined flaw. The flaw regions were monitored using strain gages and photoelasticity. These tensile tests represent the first phase of a research effort to examine and understand the variables related to pressure reversal. The second phase of this effort will be with pipe specimens and presently is in progress.

  13. Commonwealth Edison Company pressure locking test report

    SciTech Connect

    Bunte, B.D.; Kelly, J.F.

    1996-12-01

    Pressure Locking is a phenomena which can cause the unseating thrust for a gate valve to increase dramatically from its typical static unseating thrust. This can result in the valve actuator having insufficient capability to open the valve. In addition, this can result in valve damage in cases where the actuator capability exceeds the valve structural limits. For these reasons, a proper understanding of the conditions which may cause pressure locking and thermal binding, as well as a methodology for predicting the unseating thrust for a pressure locked or thermally bound valve, are necessary. This report discusses the primary mechanisms which cause pressure locking. These include sudden depressurization of piping adjacent to the valve and pressurization of fluid trapped in the valve bonnet due to heat transfer. This report provides a methodology for calculating the unseating thrust for a valve which is pressure locked. This report provides test data which demonstrates the accuracy of the calculation methodology.

  14. Corrosion Assessment of Steel Bars Used in Reinforced Concrete Structures by Means of Eddy Current Testing.

    PubMed

    de Alcantara, Naasson P; da Silva, Felipe M; Guimarães, Mateus T; Pereira, Matheus D

    2015-01-01

    This paper presents a theoretical and experimental study on the use of Eddy Current Testing (ECT) to evaluate corrosion processes in steel bars used in reinforced concrete structures. The paper presents the mathematical basis of the ECT sensor built by the authors; followed by a finite element analysis. The results obtained in the simulations are compared with those obtained in experimental tests performed by the authors. Effective resistances and inductances; voltage drops and phase angles of wound coil are calculated using both; simulated and experimental data; and demonstrate a strong correlation. The production of samples of corroded steel bars; by using an impressed current technique is also presented. The authors performed experimental tests in the laboratory using handmade sensors; and the corroded samples. In the tests four gauges; with five levels of loss-of-mass references for each one were used. The results are analyzed in the light of the loss-of-mass and show a strong linear behavior for the analyzed parameters. The conclusions emphasize the feasibility of the proposed technique and highlight opportunities for future works. PMID:26712754

  15. Corrosion Assessment of Steel Bars Used in Reinforced Concrete Structures by Means of Eddy Current Testing

    PubMed Central

    de Alcantara, Naasson P.; da Silva, Felipe M.; Guimarães, Mateus T.; Pereira, Matheus D.

    2015-01-01

    This paper presents a theoretical and experimental study on the use of Eddy Current Testing (ECT) to evaluate corrosion processes in steel bars used in reinforced concrete structures. The paper presents the mathematical basis of the ECT sensor built by the authors; followed by a finite element analysis. The results obtained in the simulations are compared with those obtained in experimental tests performed by the authors. Effective resistances and inductances; voltage drops and phase angles of wound coil are calculated using both; simulated and experimental data; and demonstrate a strong correlation. The production of samples of corroded steel bars; by using an impressed current technique is also presented. The authors performed experimental tests in the laboratory using handmade sensors; and the corroded samples. In the tests four gauges; with five levels of loss-of-mass references for each one were used. The results are analyzed in the light of the loss-of-mass and show a strong linear behavior for the analyzed parameters. The conclusions emphasize the feasibility of the proposed technique and highlight opportunities for future works. PMID:26712754

  16. Interfacial toughness of bilayer dental ceramics based on a short-bar, chevron-notch test

    PubMed Central

    Anunmana, Chuchai; Anusavice, Kenneth J.; Mecholsky, John J.

    2009-01-01

    Objective The objective of this study was to test the null hypothesis that the interfacial toughness of each of two types of bonded core-veneer bilayer ceramics is not significantly different from the apparent fracture toughness of the control monolithic glass veneer. Methods T-shaped short bars of a lithia-disilicate glass-ceramic core (LC) and yttria-stabilized polycrystalline zirconia core ceramic (ZC) were prepared according to the manufacturer's recommendations. V-shaped notches were prepared by using 25-μm-thick palladium foil, leaving the chevron notch area exposed, and the bars were veneered with a thermally compatible glass veneer (LC/GV and ZC/GV). Additionally, we also bonded the glass veneer to itself as a control group (GV/GV). Specimens were kept in distilled water for 30 days before testing in tension. Eight glass veneer bars were prepared for the analysis of fracture toughness test using the indentation-strength technique. Results The mean interfacial toughness of the LC/GV group was 0.69 [0.11] MPa·m1/2, and did not significantly differ from that of the GV/GV control group, 0.74 (0.17) MPa·m1/2 (p > 0.05). However, the difference between the mean interfacial toughness of the ZC/GV group, 0.13 (0.07) MPa·m1/2, and the LC/GV and the GV/GV groups was statistically significant (p<0.05). Significance For bilayer all-ceramic restorations with high-strength core materials, the veneering ceramics are the weakest link in the design of the structure. Since all-ceramic restorations often fail from chipping of veneer layers or crack initiation at the interface, the protective effects of thermal mismatch stresses oral prosthesis design should be investigated. PMID:19818486

  17. Stability analysis and testing of a train of centrifugal compressors for high pressure gas injection

    SciTech Connect

    Memmott, E.A.

    1999-07-01

    This paper describes the rotor dynamic stability analysis and the PTC-10 Class 1 test of a three body centrifugal compressor train for high pressure natural gas injection services. This train had a full load full pressure string test on hydrocarbon gases to a final discharge pressure of 500 BAR (7250 PSIA). Each compressor is of the back to back configuration, and is equipped with tilting pad seals, damper bearings, and a honeycomb labyrinth at the division wall with shunt holes. The driver is a gas turbine.

  18. Image-based stress and strain measurement of wood in the split-Hopkinson pressure bar

    NASA Astrophysics Data System (ADS)

    Moilanen, C. S.; Saarenrinne, P.; Engberg, B. A.; Björkqvist, T.

    2015-08-01

    The properties of wood must be considered when designing mechanical pulping machinery. The composition of wood within the annual ring is important. This paper proposes a novel image-based method to measure stress and planar strain distribution in soft, heterogeneous materials. The main advantage of this method in comparison to traditional methods that are based on strain gauges is that it captures local strain gradients and not only average strains. Wood samples were subjected to compression at strain rates of 1000-2500 s-1 in an encapsulated split-Hopkinson device. High-speed photography captured images at 50 000-100 000 Hz and different magnifications to achieve spatial resolutions of 2.9 to 9.7 µm pixels-1. The image-based analysis utilized an image correlation technique with a method that was developed for particle image velocimetry. The image analysis gave local strain distribution and average stress as a function of time. Two stress approximations, using the material properties of the split-Hopkinson bars and the displacement of the transmitter bar/sample interface, are presented. Strain gauges on the bars of the split-Hopkinson device give the reference average stress and strain. The most accurate image-based stress approximation differed from the strain gauge result by 5%.

  19. Pressure Change Measurement Leak Testing Errors

    SciTech Connect

    Pryor, Jeff M; Walker, William C

    2014-01-01

    A pressure change test is a common leak testing method used in construction and Non-Destructive Examination (NDE). The test is known as being a fast, simple, and easy to apply evaluation method. While this method may be fairly quick to conduct and require simple instrumentation, the engineering behind this type of test is more complex than is apparent on the surface. This paper intends to discuss some of the more common errors made during the application of a pressure change test and give the test engineer insight into how to correctly compensate for these factors. The principals discussed here apply to ideal gases such as air or other monoatomic or diatomic gasses; however these same principals can be applied to polyatomic gasses or liquid flow rate with altered formula specific to those types of tests using the same methodology.

  20. Hardware Testing of the BaBar Drift Chamber Electronics Upgrade (SULI paper)

    SciTech Connect

    Littlejohn, Bryce; Chu, Yiwen; Wiik, Liv; /SLAC

    2006-01-04

    The BaBar drift chamber provides position, timing, and dE/dx measurements for charged decay products of the {Upsilon}(4S) resonance at 10.58 GeV. Increasing data collection rates stemming from higher PEP II luminosities and background have highlighted dead time problems in the drift chamber's data acquisition system. A proposed upgrade, called Phase II, aims to solve the problem with the introduction of rewritable, higher-memory firmware in the DAQ front-end electronics that lowers dataflow through the system. After fabrication, the new electronics components were tested to ensure proper function and reliability before installation in the detector. Some tests checked for successful operation of individual components, while others operated entire sections of the upgraded system in a mockup drift chamber environment. This paper explains the testing process and presents results regarding performance of the upgrade electronics.

  1. Apparatus for testing high pressure injector elements

    NASA Technical Reports Server (NTRS)

    Myers, William Neill (Inventor); Scott, Ewell M. (Inventor); Forbes, John C. (Inventor); Shadoan, Michael D. (Inventor)

    1995-01-01

    An apparatus for testing and evaluating the spray pattern of high pressure fuel injector elements for use in supplying fuel to combustion engines is presented. Prior art fuel injector elements were normally tested by use of low pressure apparatuses which did not provide a purge to prevent mist from obscuring the injector element or to prevent frosting of the view windows; could utilize only one fluid during each test; and had their viewing ports positioned one hundred eighty (180 deg) apart, thus preventing optimum use of laser diagnostics. The high pressure fluid injector test apparatus includes an upper hub, an upper weldment or housing, a first clamp and stud/nut assembly for securing the upper hub to the upper weldment, a standoff assembly within the upper weldment, a pair of window housings having view glasses within the upper weldment, an injector block assembly and purge plate within the upper weldment for holding an injector element to be tested and evaluated, a lower weldment or housing, a second clamp and stud/nut assembly for securing the lower weldment to the upper hub, a third clamp and stud/nut assembly for securing the lower hub to the lower weldment, mechanisms for introducing fluid under high pressure for testing an injector element, and mechanisms for purging the apparatus to prevent frosting of view glasses within the window housings and to permit unobstructed viewing of the injector element.

  2. Apparatus for testing high pressure injector elements

    NASA Astrophysics Data System (ADS)

    Myers, William Neill; Scott, Ewell M.; Forbes, John C.; Shadoan, Michael D.

    1993-09-01

    An apparatus for testing and evaluating the spray pattern of high pressure fuel injector elements for use in supplying fuel to combustion engines is presented. Prior art fuel injector elements were normally tested by use of low pressure apparatuses which did not provide a purge to prevent mist from obscuring the injector element or to prevent frosting of the view windows; could utilize only one fluid during each test; and had their viewing ports positioned one hundred eighty (180 deg) apart, thus preventing optimum use of laser diagnostics. The high pressure fluid injector test apparatus includes an upper hub, an upper weldment or housing, a first clamp and stud/nut assembly for securing the upper hub to the upper weldment, a standoff assembly within the upper weldment, a pair of window housings having view glasses within the upper weldment, an injector block assembly and purge plate within the upper weldment for holding an injector element to be tested and evaluated, a lower weldment or housing, a second clamp and stud/nut assembly for securing the lower weldment to the upper weldment, a lower hub, a third clamp and stud/nut assembly for securing the lower hub to the lower weldment, mechanisms for introducing fluid under high pressure for testing an injector element, and mechanisms for purging the apparatus to prevent frosting of view glasses within the window housings and to permit unobstructed viewing of the injector element.

  3. Apparatus for testing high pressure injector elements

    NASA Astrophysics Data System (ADS)

    Myers, William Neill; Scott, Ewell M.; Forbes, John C.; Shadoan, Michael D.

    1995-05-01

    An apparatus for testing and evaluating the spray pattern of high pressure fuel injector elements for use in supplying fuel to combustion engines is presented. Prior art fuel injector elements were normally tested by use of low pressure apparatuses which did not provide a purge to prevent mist from obscuring the injector element or to prevent frosting of the view windows; could utilize only one fluid during each test; and had their viewing ports positioned one hundred eighty (180 deg) apart, thus preventing optimum use of laser diagnostics. The high pressure fluid injector test apparatus includes an upper hub, an upper weldment or housing, a first clamp and stud/nut assembly for securing the upper hub to the upper weldment, a standoff assembly within the upper weldment, a pair of window housings having view glasses within the upper weldment, an injector block assembly and purge plate within the upper weldment for holding an injector element to be tested and evaluated, a lower weldment or housing, a second clamp and stud/nut assembly for securing the lower weldment to the upper hub, a third clamp and stud/nut assembly for securing the lower hub to the lower weldment, mechanisms for introducing fluid under high pressure for testing an injector element, and mechanisms for purging the apparatus to prevent frosting of view glasses within the window housings and to permit unobstructed viewing of the injector element.

  4. Apparatus for testing high pressure injector elements

    NASA Technical Reports Server (NTRS)

    Myers, William Neill (Inventor); Scott, Ewell M. (Inventor); Forbes, John C. (Inventor); Shadoan, Michael D. (Inventor)

    1993-01-01

    An apparatus for testing and evaluating the spray pattern of high pressure fuel injector elements for use in supplying fuel to combustion engines is presented. Prior art fuel injector elements were normally tested by use of low pressure apparatuses which did not provide a purge to prevent mist from obscuring the injector element or to prevent frosting of the view windows; could utilize only one fluid during each test; and had their viewing ports positioned one hundred eighty (180 deg) apart, thus preventing optimum use of laser diagnostics. The high pressure fluid injector test apparatus includes an upper hub, an upper weldment or housing, a first clamp and stud/nut assembly for securing the upper hub to the upper weldment, a standoff assembly within the upper weldment, a pair of window housings having view glasses within the upper weldment, an injector block assembly and purge plate within the upper weldment for holding an injector element to be tested and evaluated, a lower weldment or housing, a second clamp and stud/nut assembly for securing the lower weldment to the upper weldment, a lower hub, a third clamp and stud/nut assembly for securing the lower hub to the lower weldment, mechanisms for introducing fluid under high pressure for testing an injector element, and mechanisms for purging the apparatus to prevent frosting of view glasses within the window housings and to permit unobstructed viewing of the injector element.

  5. High Pressure Quick Disconnect Particle Impact Tests

    NASA Technical Reports Server (NTRS)

    Rosales, Keisa R.; Stoltzfus, Joel M.

    2009-01-01

    NASA Johnson Space Center White Sands Test Facility (WSTF) performed particle impact testing to determine whether there is a particle impact ignition hazard in the quick disconnects (QDs) in the Environmental Control and Life Support System (ECLSS) on the International Space Station (ISS). Testing included standard supersonic and subsonic particle impact tests on 15-5 PH stainless steel, as well as tests performed on a QD simulator. This paper summarizes the particle impact tests completed at WSTF. Although there was an ignition in Test Series 4, it was determined the ignition was caused by the presence of a machining imperfection. The sum of all the test results indicates that there is no particle impact ignition hazard in the ISS ECLSS QDs. KEYWORDS: quick disconnect, high pressure, particle impact testing, stainless steel

  6. Reaction CH3 + OH studied over the 294-714 K temperature and 1-100 bar pressure ranges.

    PubMed

    Sangwan, Manuvesh; Chesnokov, Evgeni N; Krasnoperov, Lev N

    2012-08-30

    Reaction of methyl radicals with hydroxyl radicals, CH(3) + OH → products (1) was studied using pulsed laser photolysis coupled to transient UV-vis absorption spectroscopy over the 294-714 K temperature and 1-100 bar pressure ranges (bath gas He). Methyl radicals were produced by photolysis of acetone at 193.3 nm. Hydroxyl radicals were generated in reaction of electronically excited oxygen atoms O((1)D), produced in the photolysis of N(2)O at 193.3 nm, with H(2)O. Temporal profiles of CH(3) were recorded via absorption at 216.4 nm using xenon arc lamp and a spectrograph; OH radicals were monitored via transient absorption of light from a dc discharge H(2)O/Ar low pressure resonance lamp at ca. 308 nm. The absolute intensity of the photolysis light inside the reactor was determined by an accurate in situ actinometry based on the ozone formation in the presence of molecular oxygen. The results of this study indicate that the rate constant of reaction 1 is pressure independent within the studied pressure and temperature ranges and has slight negative temperature dependence, k(1) = (1.20 ± 0.20) × 10(-10)(T/300)(-0.49) cm(3) molecule(-1) s(-1). PMID:22846041

  7. 30 CFR 7.307 - Static pressure test.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Static pressure test. 7.307 Section 7.307... pressure test. (a) Test procedure. (1) The enclosure shall be internally pressurized to a minimum of 150 psig and the pressure maintained for a minimum of 10 seconds. (2) Following the pressure hold,...

  8. 30 CFR 7.307 - Static pressure test.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Static pressure test. 7.307 Section 7.307... pressure test. (a) Test procedure. (1) The enclosure shall be internally pressurized to a minimum of 150 psig and the pressure maintained for a minimum of 10 seconds. (2) Following the pressure hold,...

  9. 30 CFR 7.307 - Static pressure test.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Static pressure test. 7.307 Section 7.307... pressure test. (a) Test procedure. (1) The enclosure shall be internally pressurized to a minimum of 150 psig and the pressure maintained for a minimum of 10 seconds. (2) Following the pressure hold,...

  10. 30 CFR 7.307 - Static pressure test.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Static pressure test. 7.307 Section 7.307... pressure test. (a) Test procedure. (1) The enclosure shall be internally pressurized to a minimum of 150 psig and the pressure maintained for a minimum of 10 seconds. (2) Following the pressure hold,...

  11. 30 CFR 7.307 - Static pressure test.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Static pressure test. 7.307 Section 7.307... pressure test. (a) Test procedure. (1) The enclosure shall be internally pressurized to a minimum of 150 psig and the pressure maintained for a minimum of 10 seconds. (2) Following the pressure hold,...

  12. Evolvable Cryogenics (ECRYO) Pressure Transducer Calibration Test

    NASA Technical Reports Server (NTRS)

    Diaz, Carlos E., Jr.

    2015-01-01

    This paper provides a summary of the findings of recent activities conducted by Marshall Space Flight Center's (MSFC) In-Space Propulsion Branch and MSFC's Metrology and Calibration Lab to assess the performance of current "state of the art" pressure transducers for use in long duration storage and transfer of cryogenic propellants. A brief historical narrative in this paper describes the Evolvable Cryogenics program and the relevance of these activities to the program. This paper also provides a review of three separate test activities performed throughout this effort, including: (1) the calibration of several pressure transducer designs in a liquid nitrogen cryogenic environmental chamber, (2) the calibration of a pressure transducer in a liquid helium Dewar, and (3) the calibration of several pressure transducers at temperatures ranging from 20 to 70 degrees Kelvin (K) using a "cryostat" environmental chamber. These three separate test activities allowed for study of the sensors along a temperature range from 4 to 300 K. The combined data shows that both the slope and intercept of the sensor's calibration curve vary as a function of temperature. This homogeneous function is contrary to the linearly decreasing relationship assumed at the start of this investigation. Consequently, the data demonstrates the need for lookup tables to change the slope and intercept used by any data acquisition system. This ultimately would allow for more accurate pressure measurements at the desired temperature range. This paper concludes with a review of a request for information (RFI) survey conducted amongst different suppliers to determine the availability of current "state of the art" flight-qualified pressure transducers. The survey identifies requirements that are most difficult for the suppliers to meet, most notably the capability to validate the sensor's performance at temperatures below 70 K.

  13. PRSEUS Pressure Cube Test Data and Response

    NASA Technical Reports Server (NTRS)

    Lovejoy, Andrew E.

    2013-01-01

    NASA s Environmentally Responsible Aviation (ERA) Program is examining the hybrid wing body (HWB) aircraft, among others, in an effort to increase the fuel efficiency of commercial aircraft. The HWB design combines features of a flying wing with features of conventional transport aircraft, and has the advantage of simultaneously increasing both fuel efficiency and payload. Recent years have seen an increased focus on the structural performance of the HWB. The key structural challenge of a HWB airframe is the ability to create a cost and weight efficient, non-circular, pressurized shell. Conventional round fuselage sections react cabin pressure by hoop tension. However, the structural configuration of the HWB subjects the majority of the structural panels to bi-axial, in-plane loads in addition to the internal cabin pressure, which requires more thorough examination and analysis than conventional transport aircraft components having traditional and less complex load paths. To address this issue, while keeping structural weights low, extensive use of advanced composite materials is made. This report presents the test data and preliminary conclusions for a pressurized cube test article that utilizes Boeing's Pultruded Rod Stitched Efficient Unitized Structure (PRSEUS), and which is part of the building block approach used for HWB development.

  14. Adapting optical technologies for low pressure measurements in the marine industry (1-10 bar)

    NASA Astrophysics Data System (ADS)

    Sanmartin, D. Rodriguez; Lawal, A.; Awcock, G.; Busbridge, S.; Cooper, P.; Spenceley, J.

    2013-05-01

    Optical sensing is a very attractive technology option to design transducers for applications, such as the measurement of liquid level in oil fuel tanks, which require intrinsic safety and electromagnetic compatibility. PSM Instrumentation Ltd., an UK firm specialised in instrumentation for liquid level measurement for the marine industry and the University of Brighton are currently collaborating in a 2 year research programme funded by the UK government scheme Knowledge Transfer Partnerships. This paper evaluates how optical technologies could be used in pressure transducers, and their potential benefits, such as intrinsic safety compliance and low cost cabling, for low pressure applications such as fuel tank gauging for applications in the marine industry.

  15. Reaction OH + OH studied over the 298-834 K temperature and 1-100 bar pressure ranges.

    PubMed

    Sangwan, Manuvesh; Chesnokov, Evgeni N; Krasnoperov, Lev N

    2012-06-21

    Self-reaction of hydroxyl radicals, OH + OH → H(2)O + O (1a) and OH + OH → H(2)O(2) (1b), was studied using pulsed laser photolysis coupled to transient UV-vis absorption spectroscopy over the 298-834 K temperature and 1-100 bar pressure ranges (bath gas He). A heatable high-pressure flow reactor was employed. Hydroxyl radicals were prepared using reaction of electronically excited oxygen atoms, O((1)D), produced in photolysis of N(2)O at 193 nm, with H(2)O. The temporal behavior of OH radicals was monitored via transient absorption of light from a dc discharge in H(2)O/Ar low-pressure resonance lamp at ca. 308 nm. The absolute intensity of the photolysis light was determined by accurate in situ actinometry based on the ozone formation in the presence of molecular oxygen. The results of this study combined with the literature data indicate that the rate constant of reaction 1a, associated with the pressure independent component, decreases with temperature within the temperature range 298-414 K and increases above 555 K. The pressure dependent rate constant for (1b) was parametrized using the Troe expression as k(1b,inf) = (2.4 ± 0.6) × 10(-11)(T/300)(-0.5) cm(3) molecule(-1) s(-1), k(1b,0) = [He] (9.0 ± 2.2) × 10(-31)(T/300)(-3.5±0.5) cm(3) molecule(-1) s(-1), F(c) = 0.37. PMID:22397582

  16. Cerebral Critical Closing Pressure During Infusion Tests.

    PubMed

    Varsos, Georgios V; Czosnyka, Marek; Smielewski, Peter; Garnett, Matthew R; Liu, Xiuyun; Adams, Hadie; Pickard, John D; Czosnyka, Zofia

    2016-01-01

    We studied possible correlations between cerebral hemodynamic indices based on critical closing pressure (CrCP) and cerebrospinal fluid (CSF) compensatory dynamics, as assessed during lumbar infusion tests. Our data consisted of 34 patients with normal-pressure hydrocephalus who undertook an infusion test, in conjunction with simultaneous transcranial Doppler ultrasonography (TCD) monitoring of blood flow velocity (FV). CrCP was calculated from the monitored signals of ICP, arterial blood pressure (ABP), and FV, whereas vascular wall tension (WT) was estimated as CrCP - ICP. The closing margin (CM) expresses the difference between ABP and CrCP. ICP increased during infusion from 6.67 ± 4.61 to 24.98 ± 10.49 mmHg (mean ± SD; p < 0.001), resulting in CrCP rising by 22.93 % (p < 0.001), with WT decreasing by 11.33 % (p = 0.005) owing to vasodilatation. CM showed a tendency to decrease, albeit not significantly (p = 0.070), because of rising ABP (9.12 %; p = 0.005), and was significantly different from zero for the whole duration of the tests (52.78 ± 22.82 mmHg; p < 0.001). CM at baseline correlated inversely with brain elasticity (R = -0.358; p = 0.038). Neither CrCP nor WT correlated with CSF compensatory parameters. Overall, CrCP increases and WT decreases during infusion tests, whereas CM at baseline pressure may act as a characterizing indicator of the cerebrospinal compensatory reserve. PMID:27165909

  17. Dynamic testing of concrete under high confined pressure. Influence of saturation ratio and aggregate size

    NASA Astrophysics Data System (ADS)

    Forquin, P.; Piotrowska, E.; Gary, G.

    2015-09-01

    Concrete structures can be exposed to intense pressure loadings such as projectile-impact or detonation near a concrete structural element. To investigate the mechanical behaviour of concrete under high confining pressure, dynamic quasi-oedometric compression tests have been performed with a large diameter (80 mm) Split Hopkinson Pressure Bar apparatus. The concrete sample is placed within a steel confining ring and compressed along its axial direction. Hydrostatic pressures as high as 800 MPa and axial strain of about - 10% are reached during the tests. In the present work, experiments have been conducted on two types of concrete: MB50 microconcrete with a maximum grain size of 2 mm and R30A7 ordinary concrete of maximum grain size about 8 mm. Both concretes are tested in dry or saturated conditions. According to these dynamic experiments it is noted that grain size has a small influence whereas water content has a strong effect on the confined behaviour of concrete.

  18. Apparatus for Leak Testing Pressurized Hoses

    NASA Technical Reports Server (NTRS)

    Underwood, Steve D. (Inventor); Garrison, Steve G. (Inventor); Gant, Bobby D. (Inventor); Palmer, John R. (Inventor)

    2015-01-01

    A hose-attaching apparatus for leak-testing a pressurized hose may include a hose-attaching member. A bore may extend through the hose-attaching member. An internal annular cavity may extend coaxially around the bore. At least one of a detector probe hole and a detector probe may be connected to the internal annular cavity. At least a portion of the bore may have a diameter which is at least one of substantially equal to and less than a diameter of a hose to be leak-tested.

  19. Testing the Effects of Helium Pressurant on Thermodynamic Vent System Performance with Liquid Hydrogen

    NASA Technical Reports Server (NTRS)

    Flachbart, R. H.; Hastings, L. J.; Hedayat, A.; Nelson, S.; Tucker, S.

    2006-01-01

    In support of the development of a zero gravity pressure control capability for liquid hydrogen, testing was conducted at the Marshall Space Flight Center using the Multipurpose Hydrogen Test Bed (MHTB) to evaluate the effects of helium pressurant on the performance of a spray bar thermodynamic vent system (TVS). Fourteen days of testing was performed in August - September 2005, with an ambient heat leak of about 70-80 watts and tank fill levels of 90%, 50%, and 25%. The TVS successfully controlled the tank pressure within a +/- 3.45 kPa (+/- 0.5 psi) band with various helium concentration levels in the ullage. Relative to pressure control with an "all hydrogen" ullage, the helium presence resulted in 10 to 30 per cent longer pressure reduction durations, depending on the fill level, during the mixing/venting phase of the control cycle. Additionally, the automated control cycle was based on mixing alone for pressure reduction until the pressure versus time slope became positive, at which time the Joule-Thomson vent was opened. Testing was also conducted to evaluate thermodynamic venting without the mixer operating, first with liquid then with vapor at the recirculation line inlet. Although ullage stratification was present, the ullage pressure was successfully controlled without the mixer operating. Thus, if vapor surrounded the pump inlet in a reduced gravity situation, the ullage pressure can still be controlled by venting through the TVS Joule Thomson valve and heat exchanger. It was evident that the spray bar configuration, which extends almost the entire length of the tank, enabled significant thermal energy removal from the ullage even without the mixer operating. Details regarding the test setup and procedures are presented in the paper. 1

  20. Partial pressure analysis in space testing

    NASA Technical Reports Server (NTRS)

    Tilford, Charles R.

    1994-01-01

    For vacuum-system or test-article analysis it is often desirable to know the species and partial pressures of the vacuum gases. Residual gas or Partial Pressure Analyzers (PPA's) are commonly used for this purpose. These are mass spectrometer-type instruments, most commonly employing quadrupole filters. These instruments can be extremely useful, but they should be used with caution. Depending on the instrument design, calibration procedures, and conditions of use, measurements made with these instruments can be accurate to within a few percent, or in error by two or more orders of magnitude. Significant sources of error can include relative gas sensitivities that differ from handbook values by an order of magnitude, changes in sensitivity with pressure by as much as two orders of magnitude, changes in sensitivity with time after exposure to chemically active gases, and the dependence of the sensitivity for one gas on the pressures of other gases. However, for most instruments, these errors can be greatly reduced with proper operating procedures and conditions of use. In this paper, data are presented illustrating performance characteristics for different instruments and gases, operating parameters are recommended to minimize some errors, and calibrations procedures are described that can detect and/or correct other errors.

  1. Wind tunnel force and pressure tests

    NASA Technical Reports Server (NTRS)

    Wentz, W. H., Jr.

    1981-01-01

    Force and surface pressure distributions were measured for a 13% medium speed (NASA MS(1)-0313) airfoil fitted with 20% aileron, 25% slotted flap and 10% slot lip spoiler. All tests were conducted in the Walter Beech Memorial Wind Tunnel at a Reynolds number of 2.2 million and a Mach number of 0.13. Results include lift, drag, pitching moments, control surface normal force and hinge moments, and surface pressure distributions. The basic airfoil exhibits low speed characteristics similar to the GA(W)-2 airfoil. Incremental aileron and spoiler performance are quite comparable to that obtained on the GA(W)-2 airfoil. Slotted flap performance on this section is reduced compared to the GA(W)-2, resulting in a highest c sub l max of 3.00 compared to 3.35 for the GA(W)-2.

  2. KSC inventor tests cabin pressure monitor

    NASA Technical Reports Server (NTRS)

    2000-01-01

    Jan Zysko (left) and Rich Mizell (right) test a Personal Cabin Pressure Altitude Monitor in an altitude chamber at Tyndall Air Force Base in Florida. Zysko invented the pager-sized monitor that alerts wearers of a potentially dangerous or deteriorating cabin pressure altitude condition, which can lead to life- threatening hypoxia. Zysko is chief of the KSC Spaceport Engineering and Technology directorate's data and electronic systems branch. Mizell is a Shuttle processing engineer. The monitor, which has drawn the interest of such organizations as the Federal Aviation Administration for use in commercial airliners and private aircraft, was originally designed to offer Space Shuttle and Space Station crew members added independent notification about any depressurization.

  3. Liquid abrasive pressure pot scoping tests report

    SciTech Connect

    Archibald, K.E.

    1996-01-01

    The primary initiatives of the LITCO Decontamination Development group at the Idaho Chemical Process Plant (ICPP) are the development of methods to eliminate the use of sodium bearing decontamination chemicals and minimization of the amount of secondary waste generated during decontamination activities. In July of 1994, a Commerce Business Daily (CBD) announcement was issued by the INEL to determine commercial interest in the development of an in-situ liquid abrasive grit blasting system. As a result of the CBD announcement, Klieber & Schulz issued an Expression of Interest letter which stated they would be interested in testing a prototype Liquid Abrasive Pressure Pot (LAPP). LITCO`s Decontamination group and Kleiber & Schulz entered into a Cooperative Research and Development Agreement (CRADA) in which the Decontamination Development group tested the prototype LAPP in a non-radioactive hot cell mockup. Test results are provided.

  4. 30 CFR 18.67 - Static-pressure tests.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Static-pressure tests. 18.67 Section 18.67....67 Static-pressure tests. Static-pressure tests shall be conducted by the applicant on each enclosure... pressure to be applied shall be 150 pounds per square inch (gage) or one and one-half times the...

  5. 30 CFR 18.67 - Static-pressure tests.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Static-pressure tests. 18.67 Section 18.67....67 Static-pressure tests. Static-pressure tests shall be conducted by the applicant on each enclosure... pressure to be applied shall be 150 pounds per square inch (gage) or one and one-half times the...

  6. 30 CFR 18.67 - Static-pressure tests.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Static-pressure tests. 18.67 Section 18.67....67 Static-pressure tests. Static-pressure tests shall be conducted by the applicant on each enclosure... pressure to be applied shall be 150 pounds per square inch (gage) or one and one-half times the...

  7. 30 CFR 18.67 - Static-pressure tests.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Static-pressure tests. 18.67 Section 18.67....67 Static-pressure tests. Static-pressure tests shall be conducted by the applicant on each enclosure... pressure to be applied shall be 150 pounds per square inch (gage) or one and one-half times the...

  8. 30 CFR 18.67 - Static-pressure tests.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Static-pressure tests. 18.67 Section 18.67....67 Static-pressure tests. Static-pressure tests shall be conducted by the applicant on each enclosure... pressure to be applied shall be 150 pounds per square inch (gage) or one and one-half times the...

  9. Measurement of local strain and heat propagation during high-temperature testing in a split-Hopkinson tension bar system

    NASA Astrophysics Data System (ADS)

    Vilamosa, V.; Clausen, A. H.; Hopperstad, O. S.; Børvik, T.; Skjervold, S.

    2012-08-01

    Aluminium alloys are commonly used by the industry due to their good mechanical properties and their relatively low density. An accurate prediction of the behaviour of aluminium alloys under a wide range of temperatures and strain rates is important in numerical simulations of forming processes or applications involving adiabatic heating like penetration and crash situations. Several tests are needed at low, medium and high strain rates to study this behaviour. This paper will focus on the high strain rate test rig, which is a split- Hopkinson tension bar system (SHTB), the acquisition system for strain measurements, and a thermal analysis of the bars due to heating of the sample. A new way of doing local measurements with a high-speed camera will be presented. The thermal boundary conditions of the tests have been measured and simulated, and the results indicate that the stress wave propagation in the bars is not significantly affected by a local heating of the part of the bars which is closest to the sample.

  10. Watts Bar Unit 1 Cycle Zero Power Physics Tests Analysis with VERA-CS

    SciTech Connect

    Gehin, Jess C; Godfrey, Andrew T; Evans, Thomas M; Hamilton, Steven P; Francheschini, F.

    2014-01-01

    The Consortium for Advanced Simulation of Light Water Reactors (CASL) is developing a collection of methods and software products known as VERA, the Virtual Environment for Reactor Applications, including a core simulation capability called VERA-CS. A key milestone for this endeavor is to validate VERA against measurements from operating nuclear power reactors. The first step in validation against plant data is to determine the ability of VERA to accurately simulate the initial startup physics tests for Watts Bar Nuclear Power Station, Unit 1 (WBN1) cycle 1. VERA-CS calculations were performed with the Insilico code developed at ORNL using cross section processing from the SCALE system and the transport capabilities within the Denovo transport code using the SPN method. The calculations were performed with ENDF/B-VII.0 cross sections in 252 groups (collapsed to 23 groups for the 3D transport solution). The key results of the comparison of calculations with measurements include initial criticality, control rod worth critical configurations, control rod worth, differential boron worth, and isothermal temperature reactivity coefficient (ITC). The VERA results for these parameters show good agreement with measurements, with the exception of the ITC, which requires additional investigation. Results are also compared to those obtained with Monte Carlo methods and a current industry core simulator.

  11. Development and testing of an active boring bar for increased chatter immunity

    SciTech Connect

    Redmond, J.; Barney, P.

    1997-12-01

    Recent advances in smart materials have renewed interest in the development of improved manufacturing processes featuring sensing, processing, and active control. In particular, vibration suppression in metal cutting has received much attention because of its potential for enhancing part quality while reducing the time and cost of production. Although active tool clamps have been recently demonstrated, they are often accompanied by interfacing issues that limit their applicability to specific machines. Under the auspices of the Laboratory Directed Research and Development program, the project titled {open_quotes}Smart Cutting Tools for Precision Manufacturing{close_quotes} developed an alternative approach to active vibration control in machining. Using the boring process as a vehicle for exploration, a commercially available tool was modified to incorporate PZT stack actuators for active suppression of its bending modes. Since the modified tool requires no specialized mounting hardware, it can be readily mounted on many machines. Cutting tests conducted on a horizontal lathe fitted with a hardened steel workpiece verify that the actively damped boring bar yields significant vibration reduction and improved surface finishes as compared to an unmodified tool.

  12. Test plan pressure fed thrust chamber technology

    NASA Technical Reports Server (NTRS)

    Dunn, Glenn

    1990-01-01

    Aerojet is developing the technology for the design of a reliable, low cost, efficient, and lightweight LOX/RP-1 pressure fed engine. This technology program is a direct result of Aerojet's liquid rocket booster (LRB) study and previous NASA studies that identified liquid engines using high bulk density hydrocarbon fuels as very attractive for a space transportation system (STS). Previous large thrust LOX/RP-1 engine development programs were characterized by costly development problems due to combustion instability damage. The combustion stability solution was typically obtained through trial and error methods of minimizing instability damage by degrading engine performance. The approach to this program was to utilize existing and newly developed combustion analysis models and design methodology to create a thrust chamber design with features having the potential of producing reliable and efficient operation. This process resulted in an engine design with a unique high thrust-per-element OFO triplet injector utilizing a low cost modular approach. Cost efficient ablative materials are baselined for the injector face and chamber. Technology demonstration will be accomplished through a hot fire test program using appropriately sized subscale hardware. This subscale testing will provide a data base to supplement the current industry data bank and to anchor and validate the applied analysis models and design methodology. Once anchored and validated, these analysis models and design methodology can be applied with greatly increased confidence to design and characterize a large scale pressure fed LOX/RP-1 thrust chamber. The objective of this test program is to generate a data base that can be used to anchor and validate existing analysis models and design methodologies and to provide early concept demonstration of a low cost, efficient LOX/RP-1 thrust chamber. Test conditions and hardware instrumentation were defined to provide data sufficient to characterize combustion

  13. 33 CFR 183.586 - Pressure impulse test.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 2 2011-07-01 2011-07-01 false Pressure impulse test. 183.586...) BOATING SAFETY BOATS AND ASSOCIATED EQUIPMENT Fuel Systems Tests § 183.586 Pressure impulse test. A fuel... pressure test under § 183.580. (b) If the tank is non-metallic, fill it to capacity with a gasoline...

  14. 33 CFR 183.586 - Pressure impulse test.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 2 2012-07-01 2012-07-01 false Pressure impulse test. 183.586...) BOATING SAFETY BOATS AND ASSOCIATED EQUIPMENT Fuel Systems Tests § 183.586 Pressure impulse test. A fuel... pressure test under § 183.580. (b) If the tank is non-metallic, fill it to capacity with a gasoline...

  15. 30 CFR 7.104 - Internal static pressure test.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Internal static pressure test. 7.104 Section 7... Internal static pressure test. (a) Test procedures. (1) Isolate and seal each segment of the intake system... system or exhaust system to four times the maximum pressure observed in each segment during the tests...

  16. 49 CFR 178.348-5 - Pressure and leakage test.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 3 2014-10-01 2014-10-01 false Pressure and leakage test. 178.348-5 Section 178... Specifications for Containers for Motor Vehicle Transportation § 178.348-5 Pressure and leakage test. (a) Each cargo tank must be tested in accordance with § 178.345-13 and this section. (b) Pressure test....

  17. 30 CFR 7.104 - Internal static pressure test.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Internal static pressure test. 7.104 Section 7... Internal static pressure test. (a) Test procedures. (1) Isolate and seal each segment of the intake system... system or exhaust system to four times the maximum pressure observed in each segment during the tests...

  18. 30 CFR 250.1609 - Pressure testing of casing.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 2 2012-07-01 2012-07-01 false Pressure testing of casing. 250.1609 Section... Pressure testing of casing. (a) Prior to drilling the plug after cementing, all casing strings, except the drive or structural casing, shall be pressure tested. The conductor casing shall be tested to at...

  19. 33 CFR 183.586 - Pressure impulse test.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 2 2013-07-01 2013-07-01 false Pressure impulse test. 183.586...) BOATING SAFETY BOATS AND ASSOCIATED EQUIPMENT Fuel Systems Tests § 183.586 Pressure impulse test. A fuel... pressure test under § 183.580. (b) If the tank is non-metallic, fill it to capacity with a gasoline...

  20. 49 CFR 178.347-5 - Pressure and leakage test.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 3 2013-10-01 2013-10-01 false Pressure and leakage test. 178.347-5 Section 178... Specifications for Containers for Motor Vehicle Transportation § 178.347-5 Pressure and leakage test. (a) Each cargo tank must be tested in accordance with § 178.345-13 and this section. (b) Pressure test....

  1. 49 CFR 178.347-5 - Pressure and leakage test.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 3 2011-10-01 2011-10-01 false Pressure and leakage test. 178.347-5 Section 178... Specifications for Containers for Motor Vehicle Transportation § 178.347-5 Pressure and leakage test. (a) Each cargo tank must be tested in accordance with § 178.345-13 and this section. (b) Pressure test....

  2. 30 CFR 250.1609 - Pressure testing of casing.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 2 2013-07-01 2013-07-01 false Pressure testing of casing. 250.1609 Section... Pressure testing of casing. (a) Prior to drilling the plug after cementing, all casing strings, except the drive or structural casing, shall be pressure tested. The conductor casing shall be tested to at...

  3. 30 CFR 250.1609 - Pressure testing of casing.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 2 2014-07-01 2014-07-01 false Pressure testing of casing. 250.1609 Section... Pressure testing of casing. (a) Prior to drilling the plug after cementing, all casing strings, except the drive or structural casing, shall be pressure tested. The conductor casing shall be tested to at...

  4. 30 CFR 7.104 - Internal static pressure test.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Internal static pressure test. 7.104 Section 7... Internal static pressure test. (a) Test procedures. (1) Isolate and seal each segment of the intake system... system or exhaust system to four times the maximum pressure observed in each segment during the tests...

  5. 33 CFR 183.586 - Pressure impulse test.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Pressure impulse test. 183.586...) BOATING SAFETY BOATS AND ASSOCIATED EQUIPMENT Fuel Systems Tests § 183.586 Pressure impulse test. A fuel... pressure test under § 183.580. (b) If the tank is non-metallic, fill it to capacity with a gasoline...

  6. 30 CFR 7.104 - Internal static pressure test.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Internal static pressure test. 7.104 Section 7... Internal static pressure test. (a) Test procedures. (1) Isolate and seal each segment of the intake system... system or exhaust system to four times the maximum pressure observed in each segment during the tests...

  7. 49 CFR 178.347-5 - Pressure and leakage test.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 3 2014-10-01 2014-10-01 false Pressure and leakage test. 178.347-5 Section 178... Specifications for Containers for Motor Vehicle Transportation § 178.347-5 Pressure and leakage test. (a) Each cargo tank must be tested in accordance with § 178.345-13 and this section. (b) Pressure test....

  8. 49 CFR 178.348-5 - Pressure and leakage test.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 3 2013-10-01 2013-10-01 false Pressure and leakage test. 178.348-5 Section 178... Specifications for Containers for Motor Vehicle Transportation § 178.348-5 Pressure and leakage test. (a) Each cargo tank must be tested in accordance with § 178.345-13 and this section. (b) Pressure test....

  9. 33 CFR 183.586 - Pressure impulse test.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 2 2014-07-01 2014-07-01 false Pressure impulse test. 183.586...) BOATING SAFETY BOATS AND ASSOCIATED EQUIPMENT Fuel Systems Tests § 183.586 Pressure impulse test. A fuel... pressure test under § 183.580. (b) If the tank is non-metallic, fill it to capacity with a gasoline...

  10. 30 CFR 7.104 - Internal static pressure test.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Internal static pressure test. 7.104 Section 7... Internal static pressure test. (a) Test procedures. (1) Isolate and seal each segment of the intake system... system or exhaust system to four times the maximum pressure observed in each segment during the tests...

  11. 49 CFR 178.348-5 - Pressure and leakage test.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 3 2011-10-01 2011-10-01 false Pressure and leakage test. 178.348-5 Section 178... Specifications for Containers for Motor Vehicle Transportation § 178.348-5 Pressure and leakage test. (a) Each cargo tank must be tested in accordance with § 178.345-13 and this section. (b) Pressure test....

  12. 49 CFR 178.348-5 - Pressure and leakage test.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 3 2012-10-01 2012-10-01 false Pressure and leakage test. 178.348-5 Section 178... Specifications for Containers for Motor Vehicle Transportation § 178.348-5 Pressure and leakage test. (a) Each cargo tank must be tested in accordance with § 178.345-13 and this section. (b) Pressure test....

  13. 49 CFR 178.347-5 - Pressure and leakage test.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 3 2012-10-01 2012-10-01 false Pressure and leakage test. 178.347-5 Section 178... Specifications for Containers for Motor Vehicle Transportation § 178.347-5 Pressure and leakage test. (a) Each cargo tank must be tested in accordance with § 178.345-13 and this section. (b) Pressure test....

  14. Thermodynamic Vent System Performance Testing with Subcooled Liquid Methane and Gaseous Helium Pressurant

    NASA Technical Reports Server (NTRS)

    Flachbart, R. H.; Hastings, L. J.; Hedayat, A.; Nelson, S. L.; Tucker, S. P.

    2007-01-01

    Due to its high specific impulse and favorable thermal properties for storage, liquid methane (LCH4) is being considered as a candidate propellant for exploration architectures. In order to gain an -understanding of any unique considerations involving micro-gravity pressure control with LCH4, testing was conducted at the Marshall Space Flight Center using the Multipurpose Hydrogen Test Bed (MHTB) to evaluate the performance of a spray-bar thermodynamic vent system (TVS) with subcooled LCH4 and gaseous helium (GHe) pressurant. Thirteen days of testing were performed in November 2006, with total tank heat leak conditions of about 715 W and 420 W at a fill level of approximately 90%. The TVS system was used to subcool the LCH4 to a liquid saturation pressure of approximately 55.2 kPa before the tank was pressurized with GHe to a total pressure of 165.5 kPa. A total of 23 TVS cycles were completed. The TVS successfully controlled the ullage pressure within a prescribed control band but did not maintain a stable liquid saturation pressure. This was likely. due to a TVS design not optimized for this particular propellant and test conditions, and possibly due to a large artificially induced heat input directly into the liquid. The capability to reduce liquid saturation pressure as well as maintain it within a prescribed control band, demonstrated that the TVS could be used to seek and maintain a desired liquid inlet temperature for an engine (at a cost of propellant lost through the TVS vent). One special test was conducted at the conclusion of the planned test activities. Reduction of the tank ullage pressure by opening the Joule-Thomson valve (JT) without operating the pump was attempted. The JT remained open for over 9300 seconds, resulting in an ullage pressure reduction of 30 kPa. The special test demonstrated the feasibility of using the JT valve for limited ullage pressure reduction in the event of a pump failure.

  15. Characterization and modeling of mechanical behavior of single crystal titanium deformed by split-Hopkinson pressure bar

    DOE PAGESBeta

    Morrow, B. M.; Lebensohn, R. A.; Trujillo, C. P.; Martinez, D. T.; Addessio, F. L.; Bronkhorst, C. A.; Lookman, T.; Cerreta, E. K.

    2016-07-01

    Single crystal titanium samples were dynamically loaded using split-Hopkinson pressure bar (SHPB) and the resulting microstructures were examined. Characterization of the twins and dislocations present in the microstructure was conducted to understand the pathway for observed mechanical behavior. Electron backscatter diffraction (EBSD) was used to measure textures and quantify twinning. Microstructures were profusely twinned after loading, and twin variants and corresponding textures were different as a function of initial orientation. Focused ion beam (FIB) foils were created to analyze dislocation content using transmission electron microscopy (TEM). Large amounts of dislocations were present, indicating that plasticity was achieved through slip andmore » twinning together. Viscoplastic self-consistent (VPSC) modeling was used to confirm the complex order of operations during deformation. The activation of different mechanisms was highly dependent upon crystal orientation. For [0001] and View the MathML source[101¯1]-oriented crystals, compressive twinning was observed, followed by secondary tensile twinning. Furthermore, dislocations though prevalent in the microstructure, contributed to final texture far less than twinning.« less

  16. 49 CFR 178.345-13 - Pressure and leakage tests.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... adjacent cargo tanks empty and at atmospheric pressure. Each closure, except pressure relief devices and... 49 Transportation 3 2012-10-01 2012-10-01 false Pressure and leakage tests. 178.345-13 Section 178... Specifications for Containers for Motor Vehicle Transportation § 178.345-13 Pressure and leakage tests. (a)...

  17. 49 CFR 195.307 - Pressure testing aboveground breakout tanks.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... (incorporated by reference, see § 195.3). (d) For aboveground atmospheric pressure breakout tanks constructed of... 49 Transportation 3 2014-10-01 2014-10-01 false Pressure testing aboveground breakout tanks. 195... SAFETY TRANSPORTATION OF HAZARDOUS LIQUIDS BY PIPELINE Pressure Testing § 195.307 Pressure...

  18. 49 CFR 195.307 - Pressure testing aboveground breakout tanks.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... (incorporated by reference, see § 195.3). (d) For aboveground atmospheric pressure breakout tanks constructed of... 49 Transportation 3 2011-10-01 2011-10-01 false Pressure testing aboveground breakout tanks. 195... SAFETY TRANSPORTATION OF HAZARDOUS LIQUIDS BY PIPELINE Pressure Testing § 195.307 Pressure...

  19. 49 CFR 195.307 - Pressure testing aboveground breakout tanks.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... (incorporated by reference, see § 195.3). (d) For aboveground atmospheric pressure breakout tanks constructed of... 49 Transportation 3 2010-10-01 2010-10-01 false Pressure testing aboveground breakout tanks. 195... SAFETY TRANSPORTATION OF HAZARDOUS LIQUIDS BY PIPELINE Pressure Testing § 195.307 Pressure...

  20. 49 CFR 195.307 - Pressure testing aboveground breakout tanks.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... (incorporated by reference, see § 195.3). (d) For aboveground atmospheric pressure breakout tanks constructed of... 49 Transportation 3 2012-10-01 2012-10-01 false Pressure testing aboveground breakout tanks. 195... SAFETY TRANSPORTATION OF HAZARDOUS LIQUIDS BY PIPELINE Pressure Testing § 195.307 Pressure...

  1. 49 CFR 195.307 - Pressure testing aboveground breakout tanks.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... (incorporated by reference, see § 195.3). (d) For aboveground atmospheric pressure breakout tanks constructed of... 49 Transportation 3 2013-10-01 2013-10-01 false Pressure testing aboveground breakout tanks. 195... SAFETY TRANSPORTATION OF HAZARDOUS LIQUIDS BY PIPELINE Pressure Testing § 195.307 Pressure...

  2. 49 CFR 178.345-13 - Pressure and leakage tests.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... adjacent cargo tanks empty and at atmospheric pressure. Each closure, except pressure relief devices and... 49 Transportation 3 2011-10-01 2011-10-01 false Pressure and leakage tests. 178.345-13 Section 178... Specifications for Containers for Motor Vehicle Transportation § 178.345-13 Pressure and leakage tests. (a)...

  3. 49 CFR 178.345-13 - Pressure and leakage tests.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... adjacent cargo tanks empty and at atmospheric pressure. Each closure, except pressure relief devices and... 49 Transportation 3 2013-10-01 2013-10-01 false Pressure and leakage tests. 178.345-13 Section 178... Specifications for Containers for Motor Vehicle Transportation § 178.345-13 Pressure and leakage tests. (a)...

  4. 49 CFR 178.345-13 - Pressure and leakage tests.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... adjacent cargo tanks empty and at atmospheric pressure. Each closure, except pressure relief devices and... 49 Transportation 3 2014-10-01 2014-10-01 false Pressure and leakage tests. 178.345-13 Section 178... Specifications for Containers for Motor Vehicle Transportation § 178.345-13 Pressure and leakage tests. (a)...

  5. Small Two-Bar Specimen Creep Testing of Grade P91 Steel at 650°C

    NASA Astrophysics Data System (ADS)

    Ali, Balhassn S. M.; Hyde, Tom H.; Sun, Wei

    2016-03-01

    Commonly used small creep specimen types, such as ring and impression creep specimens, are capable of providing minimum creep strain rate data from small volumes of material. However, these test types are unable to provide the creep rupture data. In this paper the recently developed two-bar specimen type, which can be used to obtain minimum creep strain rate and creep rupture creep data from small volumes of material, is described. Conversion relationships are used to convert (i) the applied load to the equivalent uniaxial stress, and (ii) the load line deformation rate to the equivalent uniaxial creep strain rate. The effects of the specimen dimension ratios on the conversion factors are also discussed in this paper. This paper also shows comparisons between two-bar specimen creep test data and the corresponding uniaxial creep test data, for grade P91 steel at 650°C.

  6. 49 CFR 178.255-12 - Pressure test.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Pressure test. 178.255-12 Section 178.255-12... Specifications for Portable Tanks § 178.255-12 Pressure test. (a) Each completed portable tank prior to... 100 °F during the test, and applying a pressure of 60 psig. The tank shall be capable of holding...

  7. 49 CFR 178.255-12 - Pressure test.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 3 2014-10-01 2014-10-01 false Pressure test. 178.255-12 Section 178.255-12... Portable Tanks § 178.255-12 Pressure test. (a) Each completed portable tank prior to application of lining... the test, and applying a pressure of 60 psig. The tank shall be capable of holding the...

  8. 30 CFR 250.1609 - Pressure testing of casing.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 2 2011-07-01 2011-07-01 false Pressure testing of casing. 250.1609 Section... Operations § 250.1609 Pressure testing of casing. (a) Prior to drilling the plug after cementing, all casing strings, except the drive or structural casing, shall be pressure tested. The conductor casing shall...

  9. 49 CFR 178.255-12 - Pressure test.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 3 2011-10-01 2011-10-01 false Pressure test. 178.255-12 Section 178.255-12... Portable Tanks § 178.255-12 Pressure test. (a) Each completed portable tank prior to application of lining... the test, and applying a pressure of 60 psig. The tank shall be capable of holding the...

  10. 49 CFR 178.255-12 - Pressure test.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 3 2012-10-01 2012-10-01 false Pressure test. 178.255-12 Section 178.255-12... Portable Tanks § 178.255-12 Pressure test. (a) Each completed portable tank prior to application of lining... the test, and applying a pressure of 60 psig. The tank shall be capable of holding the...

  11. 49 CFR 178.255-12 - Pressure test.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 3 2013-10-01 2013-10-01 false Pressure test. 178.255-12 Section 178.255-12... Portable Tanks § 178.255-12 Pressure test. (a) Each completed portable tank prior to application of lining... the test, and applying a pressure of 60 psig. The tank shall be capable of holding the...

  12. Environmental Testing of Glass-Fiber/Epoxy Pressure Vessels

    NASA Technical Reports Server (NTRS)

    Faddoul, J. R.

    1987-01-01

    Pair of reports discusses long-term environmental tests of glassfiber/epoxy composite pressure vessels. Strength diminishes during long exposure to environment. Since such data necessary for accurate design of long-life structures such as pressure vessels, NASA Lewis Research Center built outdoor test stand in 1973. Test stand maintains system under constant pressure loading without frequent intervention of personnel.

  13. Apparatus and method for pressure testing closure disks

    DOEpatents

    Merten, Jr., Charles W.

    1992-01-21

    A method and device for testing the burst pressure of closure disks which provides high pressure to both sides of a disk and rapidly releases pressure from one side thereof causing a high rate of change of pressure. A hollow notched plug allows the rapid release of pressure upon rupturing. A tensile load is transmitted by a piston in combination with fluid pressure to the hollow notched plug.

  14. Apparatus and method for pressure testing closure disks

    DOEpatents

    Merten, C.W. Jr.

    1992-01-21

    A method and device are described for testing the burst pressure of closure disks which provides high pressure to both sides of a disk and rapidly releases pressure from one side thereof causing a high rate of change of pressure. A hollow notched plug allows the rapid release of pressure upon rupturing. A tensile load is transmitted by a piston in combination with fluid pressure to the hollow notched plug. 5 figs.

  15. Steam Oxidation at High Pressure

    SciTech Connect

    Holcomb, Gordon R.; Carney, Casey

    2013-07-19

    A first high pressure test was completed: 293 hr at 267 bar and 670{degrees}C; A parallel 1 bar test was done for comparison; Mass gains were higher for all alloys at 267 bar than at 1 bar; Longer term exposures, over a range of temperatures and pressures, are planned to provide information as to the commercial implications of pressure effects; The planned tests are at a higher combination of temperatures and pressures than in the existing literature. A comparison was made with longer-term literature data: The short term exposures are largely consistent with the longer-term corrosion literature; Ferritic steels--no consistent pressure effect; Austenitic steels--fine grain alloys less able to maintain protective chromia scale as pressure increases; Ni-base alloys--more mass gains above 105 bar than below. Not based on many data points.

  16. High temperature pressurized high frequency testing rig and test method

    DOEpatents

    De La Cruz, Jose; Lacey, Paul

    2003-04-15

    An apparatus is described which permits the lubricity of fuel compositions at or near temperatures and pressures experienced by compression ignition fuel injector components during operation in a running engine. The apparatus consists of means to apply a measured force between two surfaces and oscillate them at high frequency while wetted with a sample of the fuel composition heated to an operator selected temperature. Provision is made to permit operation at or near the flash point of the fuel compositions. Additionally a method of using the subject apparatus to simulate ASTM Testing Method D6079 is disclosed, said method involving using the disclosed apparatus to contact the faces of prepared workpieces under a measured load, sealing the workface contact point into the disclosed apparatus while immersing said contact point between said workfaces in a lubricating media to be tested, pressurizing and heating the chamber and thereby the fluid and workfaces therewithin, using the disclosed apparatus to impart a differential linear motion between the workpieces at their contact point until a measurable scar is imparted to at least one workpiece workface, and then evaluating the workface scar.

  17. Pressure Venting Tests of Phenolic Impregnated Carbon Ablator (PICA)

    NASA Technical Reports Server (NTRS)

    Blosser, Max L.; Knutson, Jeffrey R.

    2015-01-01

    A series of tests was devised to investigate the pressure venting behavior of one of the candidate ablators for the Orion capsule heat shield. Three different specimens of phenolic impregnated carbon ablator (PICA) were instrumented with internal pressure taps and subjected to rapid pressure changes from near vacuum to one atmosphere and simulated Orion ascent pressure histories. The specimens vented rapidly to ambient pressure and sustained no detectable damage during testing. Peak pressure differences through the thickness of a 3-inch-thick specimen were less than 1 psi during a simulated ascent pressure history.

  18. 14 CFR 25.843 - Tests for pressurized cabins.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ..., windows, and valves, must be tested as a pressure vessel for the pressure differential specified in § 25... functioning and capacity of the positive and negative pressure differential valves, and of the emergency... to show proper functioning under each possible condition of pressure, temperature, and moisture,...

  19. 14 CFR 25.843 - Tests for pressurized cabins.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ..., windows, and valves, must be tested as a pressure vessel for the pressure differential specified in § 25... functioning and capacity of the positive and negative pressure differential valves, and of the emergency... to show proper functioning under each possible condition of pressure, temperature, and moisture,...

  20. 49 CFR 178.345-13 - Pressure and leakage tests.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... be tested with the adjacent cargo tanks empty and at atmospheric pressure. Each closure, except... 49 Transportation 2 2010-10-01 2010-10-01 false Pressure and leakage tests. 178.345-13 Section 178... PACKAGINGS Specifications for Containers for Motor Vehicle Transportation § 178.345-13 Pressure and...

  1. 33 CFR 159.111 - Pressure and vacuum pulse test.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 2 2011-07-01 2011-07-01 false Pressure and vacuum pulse test... (CONTINUED) POLLUTION MARINE SANITATION DEVICES Design, Construction, and Testing § 159.111 Pressure and... installed must be subjected to 50 fillings of water at a pressure head of 7 feet or the maximum...

  2. 33 CFR 159.111 - Pressure and vacuum pulse test.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 2 2012-07-01 2012-07-01 false Pressure and vacuum pulse test... (CONTINUED) POLLUTION MARINE SANITATION DEVICES Design, Construction, and Testing § 159.111 Pressure and... installed must be subjected to 50 fillings of water at a pressure head of 7 feet or the maximum...

  3. 33 CFR 159.111 - Pressure and vacuum pulse test.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 2 2014-07-01 2014-07-01 false Pressure and vacuum pulse test... (CONTINUED) POLLUTION MARINE SANITATION DEVICES Design, Construction, and Testing § 159.111 Pressure and... installed must be subjected to 50 fillings of water at a pressure head of 7 feet or the maximum...

  4. 33 CFR 159.111 - Pressure and vacuum pulse test.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Pressure and vacuum pulse test... (CONTINUED) POLLUTION MARINE SANITATION DEVICES Design, Construction, and Testing § 159.111 Pressure and... installed must be subjected to 50 fillings of water at a pressure head of 7 feet or the maximum...

  5. Venus Pressure Chamber: A Small Testing Facility Available to the Community

    NASA Technical Reports Server (NTRS)

    Johnson, Natasha M.; Wegel, D. C.

    2011-01-01

    Venus is an inhospitable planet where the surface mean. temperature is approximately 740K and the global mean pressure is approximately 95 bars. The atmosphere is comprised mostly of CO2 (approximately 96.5%) and N2 (approximately3.5%) with trace amounts of CO and other reactive gases. Although Venus is very similar in size and mass with the Earth and is Earth's nearest planetary neighbor, it has not received many visitors from Earth, especially those that can land on the surface. The challenge most often cited for this scarcity of surface probes is the workability/survivability of instruments and equipment in Venus' harsh environment. In order to overcome this obstacle, a small pressure chamber has been acquired for use by the scientific community. It is housed at Goddard Space. Flight Center in Maryland and is available to the community for testing of small flight components, instruments and short-term experiments that require high temperatures and pressures.

  6. An equation correlating the solubility of quartz in water from 25° to 900°C at pressures up to 10,000 bars

    USGS Publications Warehouse

    Fournier, Robert O.; Potter, Robert W., II

    1982-01-01

    The solubility of quartz in water from 25° to 900°C at specific volume of the solvent ranging from about 1 to 10 and from 300° to 600°C at specific volume of the solvent ranging from about 10 to 100 is given by an empirically derived equation of the form: log m = A + B(log V) + C(log V)2 where m is the molal silica concentration, V is the specific volume of pure water, and A = −4.66206 + 0.0034063T + 2179.7T−1 − 1.1292 × 106T−2 + 1.3543 × 108T−3B = −0.0014180T— 806.97T−1C = 3.9465 × 10−4T T is temperature in kelvins. The experimental data used in formulating the empirical relation ranged in pressure from 1 bar at 25°C to about 10,000 bars at 900°C, and the lowest pressure in the low-density steam region was about 30 bars. According to the above equation, the average difference in molality between 518 measured and calculated solubilities is −0.016 m with a standard deviation of 0.089.

  7. 49 CFR 178.348-5 - Pressure and leakage test.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Pressure and leakage test. 178.348-5 Section 178... PACKAGINGS Specifications for Containers for Motor Vehicle Transportation § 178.348-5 Pressure and leakage test. (a) Each cargo tank must be tested in accordance with § 178.345-13 and this section. (b)...

  8. 49 CFR 178.347-5 - Pressure and leakage test.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Pressure and leakage test. 178.347-5 Section 178... PACKAGINGS Specifications for Containers for Motor Vehicle Transportation § 178.347-5 Pressure and leakage test. (a) Each cargo tank must be tested in accordance with § 178.345-13 and this section. (b)...

  9. Triple bar, high efficiency mechanical sealer

    DOEpatents

    Pak, Donald J.; Hawkins, Samantha A.; Young, John E.

    2013-03-19

    A clamp with a bottom clamp bar that has a planar upper surface is provided. The clamp may also include a top clamp bar connected to the bottom clamp bar, and a pressure distribution bar between the top clamp bar and the bottom clamp bar. The pressure distribution bar may have a planar lower surface in facing relation to the upper surface of the bottom clamp bar. An object is capable of being disposed in a clamping region between the upper surface and the lower surface. The width of the planar lower surface may be less than the width of the upper surface within the clamping region. Also, the pressure distribution bar may be capable of being urged away from the top clamp bar and towards the bottom clamp bar.

  10. Air jet erosion test on plasma sprayed surface by varying erodent impingement pressure and impingement angle

    NASA Astrophysics Data System (ADS)

    Behera, Ajit; Behera, Asit; Mishra, S. C.; Pani, S.; Parida, P.

    2015-02-01

    Fly-ash premixed with quartz and illmenite powder in different weight proportions are thermal sprayed on mild steel and copper substrates at various input power levels of the plasma torch ranging from 11 kW to 21 kW DC. The erosion test has done using Air Jet erosion test Reg (As per ASTM G76) with silica erodent typically 150-250 pm in size. Multiple tests were performed at increasing the time duration from 60 sec to 180 sec with increasing pressure (from 1 bar to 2.5 bar) and angle (60° & 90°). This study reveals that the impact velocity and impact angle are two most significant parameters among various factors influencing the wear rate of these coatings. The mechanisms and microstructural changes that arise during erosion wear are studied by using SEM. It is found that, when erodent are impacting the fresh un-eroded surface, material removal occurs by the continuous evolution of craters on the surface. Upper layer splats are removed out after 60 sec and second layer splat erosion starts. Based on these observations Physical models are developed. Some graphs plotted between mass loss-rate versus time period/impact Pressure/impact Angle gives good correlation with surface features observed.

  11. Pressure Roller For Tape-Lift Tests

    NASA Technical Reports Server (NTRS)

    Abrams, Eve

    1991-01-01

    Rolling device applies nearly constant, uniform pressure to surface. Simple tool exerts nearly constant pressure via compression of sheath by fixed amount. Pins hold wheels on cylinder and cylinder on tangs of handle. Cylinder and handle made of metal or plastic. Sheath press-fit or glued to cylinder. End pins attached to cylinder by adhesive or screw threads. Device intended for use in taking tape-lift samples of particulate contamination on surface.

  12. Analyzing the Use of Gaseous Helium as a Pressurant with Cryogenic Propellants with Thermodynamic Venting System Modelling and Test Data

    NASA Astrophysics Data System (ADS)

    Hedayat, A.; Nelson, S. L.; Hastings, L. J.; Flachbart, R. H.; Vermilion, D. J.; Tucker, S. P.

    2008-03-01

    Cryogens are viable candidate propellants for NASA's Lunar and Mars exploration programs. To provide adequate mass flow to the system's engines and/or prevent feed system cavitation, gaseous helium (GHe) is frequently considered as a pressurant. A Thermodynamic Venting System (TVS) is designed to maintain tank pressure during low gravity operations without propellant resettling. Tests were conducted in the Marshall Space Flight Center (MSFC) Multi-purpose Hydrogen Test Bed (MHTB) to evaluate the effects of GHe pressurant on pressure control performance of a TVS with liquid hydrogen (LH2) and nitrogen (LN2) test liquids. The TVS used comprises a recirculation pump, a Joule-Thomson (J-T) expansion valve, and a parallel flow concentric tube heat exchanger combined with a longitudinal spray bar. A small amount of liquid extracted from the tank recirculation line was passed through the J-T valve and then through the heat exchanger, extracting thermal energy from the bulk liquid and ullage and thereby enabling pressure control. The LH2/GHe tests were performed at fill levels of 90%, 50%, and 25%, and LN2/GHe tests were conducted at fill levels of 50% and 25%. Moreover, each test was conducted with a specified tank ullage pressure control band. A one-dimensional TVS performance program was used to analyze and correlate the test data. Predictions were compared with test data of ullage pressure and temperature and bulk liquid saturation pressure and temperature.

  13. Experimental and theoretical investigations on the transmission of sound through single and double plates in air and helium at pressures up to 50 bars

    NASA Astrophysics Data System (ADS)

    Kehr, M.

    1980-07-01

    The thermal insulation in hot gas ducts of high temperature reactors (HTR) is subjected to dynamic loads due to pressure fluctuations. These fluctuations which are caused by turbomachines or by turbulent pipe flow may cause mechanical failures. To find out the transmission of sound energy through the structure of the insulation it is necessary to make investigations at pressures up to 50 bars with He. The radiation of sound by blowers and the propagation of sound in circular tubes is considered. The transmission of sound through a single and a double plate is calculated based on computations by the methods of room acoustics and statistical energy analysis (SEA) derived for conditions at ambient pressure. The transmission of sound through single and double plates was investigated in a tube at pressures up to 50 bars with air and He. The results of these experiments were compared with the theoretical predictions. Especially at higher frequencies the agreement between theory and experimental results are good. The main parameter influencing sound transmission is the wave resistance.

  14. Pressure relief valve/safety relief valve testing

    SciTech Connect

    Murray, W.A.; Hamm, E.R.; Barber, J.R.

    1994-02-01

    Pressure vessels and piping systems are protected form overpressurization by pressure relief valves. These safety features are required to be tested-inspected on some periodic basis and, in most cases witnessed by a third party inspector. As a result nonconformances found by third parties Westinghouse Hanford Company initiated a task team to develop a pressure safety program. This paper reveals their findings.

  15. Adapter assembly prevents damage to tubing during high pressure tests

    NASA Technical Reports Server (NTRS)

    Stinett, L. L.

    1965-01-01

    Portable adapter assembly prevents damage to tubing and injury to personnel when pressurizing a system or during high pressure tests. The assembly is capable of withstanding high pressure. It is securely attached to the tubing stub end and may be removed without brazing, cutting or cleaning the tube.

  16. Pressure measurement. [liquid monopropellant rocket engine performance tests

    NASA Technical Reports Server (NTRS)

    1979-01-01

    Practices are outlined for the design, installation, checkout, calibration, and operation of a pressure measuring system to be used during tests of a liquid monopropellant rocket engine. Appendixes include: (1) pressure measurement system elemental uncertainties; (2) short- and long-term pressure measurement system uncertainty; (3) shunt calibration of pressure transducers; (4) special considerations for vacuum measurement; and (5) methods of determining the dynamic characteristics of pressure transducers. Design guidelines are provided for the critical components of each portion of the system to provide a pressure measurement system which meets the performance criteria specified.

  17. Interpretation of prematurely terminated air-pressurized slug tests

    USGS Publications Warehouse

    Shapiro, Allen M.; Greene, Earl A.

    1995-01-01

    An air-pressurized slug test consists of applying a constant pressure to the column of air in a well, monitoring the declining water level, and then releasing the air pressure and monitoring the recovering water level. Such tests offer a means of estimating formation transmissivity and storativity without extensive downhole equipment and the associated safety risks. This paper analyzes data from prematurely terminated tests. A solution to the boundary-value problem for the declining and recovering water level during an air-pressurized slug test is developed for an arbitrary time-dependent air pressure applied to the well. Type curves are generated to estimate formation transmissivity and storativity from the recovering water level associated with prematurely, terminated tests. The application of the type curves is illustrated in a series of actual tests.

  18. Low-Cost, Lightweight Pressure Vessel Proof Test

    NASA Astrophysics Data System (ADS)

    Chanez, Eric

    This experiment seeks to determine the burst strength of the low-cost, lightweight pressure vessel fabricated by the Suborbital Center of Excellence (SCE). Moreover, the test explores the effects of relatively large gage pressures on material strain for ‘pumpkin-shaped' pressure vessels. The SCE team used pressure transducers and analog gauges to measure the gage pressure while a video camera assembly recorded several gores in the shell for strain analysis. The team loaded the vessel in small intervals of pressure until the structure failed. Upon test completion, the pressure readings and video recordings were analyzed to determine the burst strength and material strain in the shell. The analysis yielded a burst pressure of 13.5 psi while the strain analysis reported in the shell. While the results of this proof test are encouraging, the structure's factor of safety must be increased for actual balloon flights. Furthermore, the pressure vessel prototype must be subjected to reliability tests to show the design can sustain gage pressures for the length of a balloon flight.

  19. Flight testing of a luminescent surface pressure sensor

    NASA Technical Reports Server (NTRS)

    Mclachlan, B. G.; Bell, J. H.; Espina, J.; Gallery, J.; Gouterman, M.; Demandante, C. G. N.; Bjarke, L.

    1992-01-01

    NASA ARC has conducted flight tests of a new type of aerodynamic pressure sensor based on a luminescent surface coating. Flights were conducted at the NASA ARC-Dryden Flight Research Facility. The luminescent pressure sensor is based on a surface coating which, when illuminated with ultraviolet light, emits visible light with an intensity dependent on the local air pressure on the surface. This technique makes it possible to obtain pressure data over the entire surface of an aircraft, as opposed to conventional instrumentation, which can only make measurements at pre-selected points. The objective of the flight tests was to evaluate the effectiveness and practicality of a luminescent pressure sensor in the actual flight environment. A luminescent pressure sensor was installed on a fin, the Flight Test Fixture (FTF), that is attached to the underside of an F-104 aircraft. The response of one particular surface coating was evaluated at low supersonic Mach numbers (M = 1.0-1.6) in order to provide an initial estimate of the sensor's capabilities. This memo describes the test approach, the techniques used, and the pressure sensor's behavior under flight conditions. A direct comparison between data provided by the luminescent pressure sensor and that produced by conventional pressure instrumentation shows that the luminescent sensor can provide quantitative data under flight conditions. However, the test results also show that the sensor has a number of limitations which must be addressed if this technique is to prove useful in the flight environment.

  20. Inservice leak testing of primary pressure isolation valves

    SciTech Connect

    Livingston, R.A.

    1983-02-01

    This report discusses the inservice leak testing of primary pressure isolation valves in commercial power reactors which was investigated to identify problems with current test procedures and requirements. Nine utilities were surveyed to gather information which is presented in this report. An analysis of the survey information was performed, resulting in recommended changes to improve valve leak testing requirements currently invoked by Section XI of the ASME Boiler and Pressure Vessel Code, Plant Technical Specifications, and Regulatory Guides addressing this subject.

  1. Test and evaluation of pressure transducers for a reentry vehicle pressure measurement system

    NASA Technical Reports Server (NTRS)

    Gibson, Lorelei S.; Sealey, Bradley S.

    1993-01-01

    The Pressure Distribution and Air Data System experiment was designed to obtain accurate pressure measurements on the windward surface of an aeroassist flight research vehicle during its aeropass through the earth's atmosphere. These pressure measurements were intended to provide air data and support CFD code validation for future aeroassist orbital transfer vehicle designs. The system consisted of a flush orifice configuration connected by tubing to a specially ranged and selected pressure transducer. The purpose of this paper is to describe the flight acceptance test program and test results leading to the selection of flight transducers.

  2. Reduced Pressure Cabin Testing of the Orion Atmosphere Revitalization Technology

    NASA Technical Reports Server (NTRS)

    Button, Amy B.; Sweterlitsch, Jeffrey J.

    2013-01-01

    An amine-based carbon dioxide (CO2) and water vapor sorbent in pressure-swing regenerable beds has been developed by United Technologies Corp. Aerospace Systems (UTAS, formerly Hamilton Sundstrand) and baselined for the Atmosphere Revitalization System for moderate duration missions of the Orion Multipurpose Crew Vehicle (MPCV). In previous years at this conference, reports were presented on extensive Johnson Space Center testing of this technology in a sea-level pressure environment with simulated and actual human metabolic loads in both open and closed-loop configurations. In 2011, the technology was tested in an open cabin-loop configuration at ambient and two sub-ambient pressures to compare the performance of the system to the results of previous tests at ambient pressure. The testing used a human metabolic simulator with a different type of water vapor generation than previously used, which added some unique challenges in the data analysis. This paper summarizes the results of: baseline and some matrix testing at all three cabin pressures, increased vacuum regeneration line pressure testing with a high metabolic load, a set of tests studying CO2 and water vapor co-adsorption effects relative to model-predicted performance, and validation tests of flight project computer model predictions with specific operating conditions.

  3. Acoustic emission testing of 12-nickel maraging steel pressure vessels

    NASA Technical Reports Server (NTRS)

    Dunegan, H. L.

    1973-01-01

    Acoustic emission data were obtained from three point bend fracture toughness specimens of 12-nickel maraging steel, and two pressure vessels of the same material. One of the pressure vessels contained a prefabricated flaw which was extended and sharpened by fatigue cycling. It is shown that the flawed vessel had similar characteristics to the fracture specimens, thereby allowing estimates to be made of its nearness to failure during a proof test. Both the flawed and unflawed pressure vessel survived the proof pressure and 5 cycles to the working pressure, but it was apparent from the acoustic emission response during the proof cycle and the 5 cycles to the working pressure that the flawed vessel was very near failure. The flawed vessel did not survive a second cycle to the proof pressure before failure due to flaw extension through the wall (causing a leak).

  4. Orion ECLSS/Suit System - Ambient Pressure Integrated Suit Test

    NASA Technical Reports Server (NTRS)

    Barido, Richard A.

    2012-01-01

    The Ambient Pressure Integrated Suit Test (APIST) phase of the integrated system testing of the Orion Vehicle Atmosphere Revitalization System (ARS) technology was conducted for the Multipurpose Crew Vehicle (MPCV) Program within the National Aeronautics and Space Administration (NASA) Exploration Systems Mission Directorate. Crew and Thermal Systems Division performed this test in the eleven-foot human-rated vacuum chamber at the NASA Johnson Space Center. This testing is the first phase of suit loop testing to demonstrate the viability of the Environmental Control and Life Support System (ECLSS) being developed for Orion. APIST is the first in a series, which will consist of testing development hardware including the Carbon dioxide and Moisture Removal Amine Swing-bed (CAMRAS) and the air revitalization loop fan with human test subjects in pressure suits at varying suit pressures. Follow-on testing, to be conducted in 2013, will utilize the CAMRAS and a development regulator with human test subjects in pressure suits at varying cabin and suit pressures. This paper will discuss the results and findings of APIST and will also discuss future testing.

  5. Expandable rubber plug seals openings for pressure testing

    NASA Technical Reports Server (NTRS)

    1966-01-01

    Plug assembly seals openings in piping systems, vessels, and chambers for low pressure leak testing. The assembly, which consists of a rubber sealing plug and the mechanism for expanding it into a pressure-tight configuration, adequately seals irregular diameters without damage to mating surfaces.

  6. Pressure Balanced, Low Hysteresis Finger Seal Test Results

    NASA Technical Reports Server (NTRS)

    Arora, Gul K.; Proctor, Margaret; Steinetz, Bruce M.; Delgado, Irebert R.

    2000-01-01

    The purpose of this presentation is to demonstrate: low cost photoetching fabrication technique; pressure balanced finger seal design; and finger seal operation. The tests and analyses includes: finger seal air leakage analysis; rotor-run out and endurance tests; and extensive analytical work and rig testing.

  7. ARL Explosive Blast Bar Gauge Response Simulation

    NASA Astrophysics Data System (ADS)

    Sutherland, Gerrit; Boyle, Vincent; Benjamin, Richard

    2013-06-01

    Simulations allow us to optimize the design of a bar gauge. The incident blast wave imparts a wave that travels down the metal bar. Strain gauges positioned along the bar measure the strain produced by the bar wave, allowing determination of pressure and impulse at the bar face. The measured pressure history depends on the arrangement of the bar gauge. If a large metal plate surrounds the bar face, a reflected blast pressure is measured. If a metal fixture that forms a nozzle surrounds the bar face, the initial pressure will be the same as above. In time, release waves emanating from the nozzle edge will decrease the pressure at the bar face. The bar diameter and size of strain gauges control the time response or gauge bandwidth. CTH hydrocode simulations allow optimization of bar gauge features for various size explosive charges. The simulations predicted the response of the metal plate arrangement to a blast from a spherical composition C4 charge. The simulations predicted the proper metal plate diameter for a reflected pressure measurement. Other simulations compared the response of the bar gauge for both configurations (nozzle or plate surround) when subjected to the same blast loading. Pressure histories from simulations were compared to those from experiment and those predicted by the CONWEP blast code. The initial experimental and CONWEP pressures were in reasonable agreement.

  8. Reduced Pressure Cabin Testing of the Orion Atmosphere Revitalization Technology

    NASA Technical Reports Server (NTRS)

    Button, Amy; Sweterlisch, Jeffery J.

    2013-01-01

    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 Atmosphere Revitalization System for moderate duration missions of the Orion Multipurpose Crew Vehicle. In previous years at this conference, reports were presented on extensive Johnson Space Center testing of this technology in a sea-level pressure environment with simulated and actual human metabolic loads in both open and closed-loop configurations. In 2011, the technology was tested in an open cabin-loop configuration at ambient and two sub-ambient pressures to compare the performance of the system to the results of previous tests at ambient pressure. The testing used a human metabolic simulator with a different type of water vapor generation than previously used, which added some unique challenges in the data analysis. This paper summarizes the results of: baseline and some matrix testing at all three cabin pressures, increased vacuum regeneration line pressure with a high metabolic load, a set of tests studying CO2 and water vapor co-adsorption effects relative to model-predicted performance, and validation tests of flight program computer model predictions with specific operating conditions.

  9. Dual-pump CARS of Air in a Heated Pressure Vessel up to 55 Bar and 1300 K

    NASA Technical Reports Server (NTRS)

    Cantu, Luca; Gallo, Emanuela; Cutler, Andrew D.; Danehy, Paul M.

    2014-01-01

    Dual-pump Coherent anti-Stokes Raman scattering (CARS) measurements have been performed in a heated pressure vessel at NASA Langley Research Center. Each measurement, consisting of 500 single shot spectra, was recorded at a fixed location in dry air at various pressures and temperatures, in a range of 0.03-55×10(exp 5) Pa and 300-1373 K, where the temperature was varied using an electric heater. The maximum output power of the electric heater limited the combinations of pressures and temperatures that could be obtained. Charts of CARS signal versus temperature (at constant pressure) and signal versus pressure (at constant temperature) are presented and fit with an empirical model to validate the range of capability of the dual-pump CARS technique; averaged spectra at different conditions of pressure and temperature are also shown.

  10. Pressure Testing of a Minimum Gauge PRSEUS Panel

    NASA Technical Reports Server (NTRS)

    Lovejoy, Andrew J.; Rouse, Marshall; Linton, Kim A.; Li, Victor P.

    2011-01-01

    Advanced aircraft configurations that have been developed to increase fuel efficiency require advanced, novel structural concepts capable of handling the unique load conditions that arise. One such concept is the Pultruded Rod Stitched Efficient Unitized Structure (PRSEUS) developed by the Boeing Company. The PRSEUS concept is being investigated by NASA s Environmentally Responsible Aviation (ERA) Program for use in a hybrid-wing body (HWB) aircraft. This paper summarizes the analysis and test of a PRSEUS panel subjected to internal pressure, the first such pressure test for this structural concept. The pressure panel used minimum gauge skin, with stringer and frame configurations consistent with previous PRSEUS tests. Analysis indicated that for the minimum gauge skin panel, the stringer locations exhibit fairly linear response, but the skin bays between the stringers exhibit nonlinear response. Excellent agreement was seen between nonlinear analysis and test results in the critical portion at the center of the panel. The pristine panel was capable of withstanding the required 18.4 psi pressure load condition without exhibiting any damage. The impacted panel was capable of withstanding a pressure load in excess of 28 psi before initial failure occurred at the center stringer, and the panel was capable of sustaining increased pressure load after the initial failure. This successful PRSEUS panel pressure panel test was a critical step in the building block approach for enabling the use of this advanced structural concept on future aircraft, such as the HWB.

  11. Constant pressure high throughput membrane permeation testing system

    DOEpatents

    Albenze, Erik J.; Hopkinson, David P.; Luebke, David R.

    2014-09-02

    The disclosure relates to a membrane testing system for individual evaluation of a plurality of planar membranes subjected to a feed gas on one side and a sweep gas on a second side. The membrane testing system provides a pressurized flow of a feed and sweep gas to each membrane testing cell in a plurality of membrane testing cells while a stream of retentate gas from each membrane testing cell is ported by a retentate multiport valve for sampling or venting, and a stream of permeate gas from each membrane testing cell is ported by a permeate multiport valve for sampling or venting. Back pressure regulators and mass flow controllers act to maintain substantially equivalent gas pressures and flow rates on each side of the planar membrane throughout a sampling cycle. A digital controller may be utilized to position the retentate and permeate multiport valves cyclically, allowing for gas sampling of different membrane cells over an extended period of time.

  12. Evaluation of the concept of pressure proof testing fuselage structures

    NASA Technical Reports Server (NTRS)

    Harris, Charles E.; Orringer, Oscar

    1991-01-01

    The FAA and NASA have recently completed independent technical evaluations of the concept of pressure proof testing the fuselage of commercial transport airplanes. The results of these evaluations are summarized. The objectives of the evaluations were to establish the potential benefit of the pressure proof test, to quantify the most desirable proof test pressure, and to quantify the required proof test interval. The focus of the evaluations was on multiple-site cracks extending from adjacent rivet holes of a typical fuselage longitudinal lap splice joint. The FAA and NASA do not support pressure proof testing the fuselage of aging commercial transport aircraft. The argument against proof testing is as follows: (1) a single proof test does not insure an indefinite life; therefore, the proof test must be repeated at regular intervals; (2) for a proof factor of 1.33, the required proof test interval must be below 300 flights to account for uncertainties in the evaluation; (3) conducting the proof test at a proof factor of 1.5 would considerably exceed the fuselage design limit load; therefore, it is not consistent with accepted safe practices; and (4) better safety can be assured by implementing enhanced nondestructive inspection requirements, and adequate reliability can be achieved by an inspection interval several times longer than the proof test interval.

  13. Normal-Pressure Tests of Circular Plates with Clamped Edges

    NASA Technical Reports Server (NTRS)

    Mcpherson, Albert E; Ramberg, Walter; Levy, Samuel

    1942-01-01

    A fixture is described for making normal-pressure tests of flat plates 5 inches in diameter in which particular care was taken to obtain rigid clamping at the edges. Results are given for 19 plates, ranging in thickness form 0.015 to 0.072 inch. The center deflections and the extreme-fiber stresses at low pressures were found to agree with theoretical values; the center deflections at high pressures were 4 to 12 percent greater than the theoretical values. Empirical curves are derived of the pressure for the beginning of the permanent set as a function of the dimensions of the plate and the tensile properties of the material.

  14. Thermodynamic Properties of Nitrogen Including Liquid and Vapor Phases from 63K to 2000K with Pressures to 10,000 Bar

    NASA Technical Reports Server (NTRS)

    Jacobsen, Richard T.; Stewart, Richard B.

    1973-01-01

    Tables of thermodynamic properties of nitrogen are presented for the liquid and vapor phases for temperatures from the freezing line to 2000K and pressures to 10,000 bar. The tables include values of density, internal energy, enthalpy, entropy, isochoric heat capacity, isobaric heat capacity velocity of sound, the isotherm derivative, and the isochor derivative. The thermodynamic property tables are based on an equation of state, P=P (p,T), which accurately represents liquid and gaseous nitrogen for the range of pressures and temperatures covered by the tables. Comparisons of property values calculated from the equation of state with measured values for P-p-T, heat capacity, enthalpy, latent heat, and velocity of sound are included to illustrate the agreement between the experimental data and the tables of properties presented here. The coefficients of the equation of state were determined by a weighted least squares fit to selected P-p-T data and, simultaneously, to isochoric heat capacity data determined by corresponding states analysis from oxygen data, and to data which define the phase equilibrium criteria for the saturated liquid and the saturated vapor. The vapor pressure equation, melting curve equation, and an equation to represent the ideal gas heat capacity are also presented. Estimates of the accuracy of the equation of state, the vapor pressure equation, and the ideal gas heat capacity equation are given. The equation of state, derivatives of the equation, and the integral functions for calculating derived thermodynamic properties are included.

  15. Laser-induced fluorescence of ketones at elevated temperatures for pressures up to 20 bars by using a 248 nm excitation laser wavelength: experiments and model improvements.

    PubMed

    Braeuer, Andreas; Beyrau, Frank; Leipertz, Alfred

    2006-07-10

    Laser-induced fluorescence of acetone and 3-pentanone for a 248 nm excitation wavelength was investigated for conditions relevant for internal combustion engines regarding temperature, pressure, and gas composition. An optically accessible calibration chamber with continuous gas flow was operated by using CO2 and air as a bath gas. According to the varying pressure and temperature conditions during the compression stroke of a spark ignition engine, fluorescence experiments were performed under isothermal pressure variations from 1 to 20 bars for different temperatures between 293 and 700 K. The ketone fluorescence behavior predictions, based on a model previously developed by Thurber et al. [Appl. Opt. 37, 4963 (1998)], were found to overestimate the pressure-related fluorescence increase for high temperature and small wavelength excitation at 248 nm. The parameters influencing the model only in the large vibrational energy regime were newly adjusted, which resulted in an improved model with a better agreement with the experiment. The model's validity for excitation at larger wavelengths was not influenced. For the air bath gas an additional collision and vibrational energy sensitive quenching rate was implemented in the model for both tracers, acetone and 3-pentanone. PMID:16807609

  16. Laser-induced fluorescence of ketones at elevated temperatures for pressures up to 20 bars by using a 248 nm excitation laser wavelength: experiments and model improvements

    NASA Astrophysics Data System (ADS)

    Braeuer, Andreas; Beyrau, Frank; Leipertz, Alfred

    2006-07-01

    Laser-induced fluorescence of acetone and 3-pentanone for a 248 nm excitation wavelength was investigated for conditions relevant for internal combustion engines regarding temperature, pressure, and gas composition. An optically accessible calibration chamber with continuous gas flow was operated by using CO2 and air as a bath gas. According to the varying pressure and temperature conditions during the compression stroke of a spark ignition engine, fluorescence experiments were performed under isothermal pressure variations from 1 to 20 bars for different temperatures between 293 and 700 K. The ketone fluorescence behavior predictions, based on a model previously developed by Thurber et al. [Appl. Opt. 37, 4963 (1998)], were found to overestimate the pressure-related fluorescence increase for high temperature and small wavelength excitation at 248 nm. The parameters influencing the model only in the large vibrational energy regime were newly adjusted, which resulted in an improved model with a better agreement with the experiment. The model's validity for excitation at larger wavelengths was not influenced. For the air bath gas an additional collision and vibrational energy sensitive quenching rate was implemented in the model for both tracers, acetone and 3-pentanone.

  17. Liquid Oxygen Thermodynamic Vent System Testing with Helium Pressurization

    NASA Technical Reports Server (NTRS)

    VanDresar, Neil T.

    2014-01-01

    This report presents the results of several thermodynamic vent system (TVS) tests with liquid oxygen plus a test with liquid nitrogen. In all tests, the liquid was heated above its normal boiling point to 111 K for oxygen and 100 K for nitrogen. The elevated temperature was representative of tank conditions for a candidate lunar lander ascent stage. An initial test series was conducted with saturated oxygen liquid and vapor at 0.6 MPa. The initial series was followed by tests where the test tank was pressurized with gaseous helium to 1.4 to 1.6 MPa. For these tests, the helium mole fraction in the ullage was quite high, about 0.57 to 0.62. TVS behavior is different when helium is present than when helium is absent. The tank pressure becomes the sum of the vapor pressure and the partial pressure of helium. Therefore, tank pressure depends not only on temperature, as is the case for a pure liquid-vapor system, but also on helium density (i.e., the mass of helium divided by the ullage volume). Thus, properly controlling TVS operation is more challenging with helium pressurization than without helium pressurization. When helium was present, the liquid temperature would rise with each successive TVS cycle if tank pressure was kept within a constant control band. Alternatively, if the liquid temperature was maintained within a constant TVS control band, the tank pressure would drop with each TVS cycle. The final test series, which was conducted with liquid nitrogen pressurized with helium, demonstrated simultaneous pressure and temperature control during TVS operation. The simultaneous control was achieved by systematic injection of additional helium during each TVS cycle. Adding helium maintained the helium partial pressure as the liquid volume decreased because of TVS operation. The TVS demonstrations with liquid oxygen pressurized with helium were conducted with three different fluid-mixer configurations-a submerged axial jet mixer, a pair of spray hoops in the tank

  18. Beryllium pressure vessels for creep tests in magnetic fusion energy

    SciTech Connect

    Neef, W.S.

    1990-07-20

    Beryllium has interesting applications in magnetic fusion experimental machines and future power-producing fusion reactors. Chief among the properties of beryllium that make these applications possible is its ability to act as a neutron multiplier, thereby increasing the tritium breeding ability of energy conversion blankets. Another property, the behavior of beryllium in a 14-MeV neutron environment, has not been fully investigated, nor has the creep behavior of beryllium been studied in an energetic neutron flux at thermodynamically interesting temperatures. This small beryllium pressure vessel could be charged with gas to test pressures around 3, 000 psi to produce stress in the metal of 15,000 to 20,000 psi. Such stress levels are typical of those that might be reached in fusion blanket applications of beryllium. After contacting R. Powell at HEDL about including some of the pressure vessels in future test programs, we sent one sample pressure vessel with a pressurizing tube attached (Fig. 1) for burst tests so the quality of the diffusion bond joints could be evaluated. The gas used was helium. Unfortunately, budget restrictions did not permit us to proceed in the creep test program. The purpose of this engineering note is to document the lessons learned to date, including photographs of the test pressure vessel that show the tooling necessary to satisfactorily produce the diffusion bonds. This document can serve as a starting point for those engineers who resume this task when funds become available.

  19. Analyzing the Use of Gaseous Helium as a Pressurant with Cryogenic Propellants with Thermodynamic Venting System Modelling and Test Data

    NASA Technical Reports Server (NTRS)

    Hedayat, A.; Nelson, S.L.; Hastings, L.J.; Flachbart, R.H.; Vermillion, D.J.; Tucker, S.P.

    2007-01-01

    Cryogens are viable candidate propellants for NASA's Lunar and Mars exploration programs. To provide adequate mass flow to the system's engines and/or to prevent feed system cavitation, gaseous helium (GHe) is frequently considered as a pressurant. During low gravity operations, a Thermodynamic Venting System (TVS) is designed to maintain tank pressure during low gravity operations without propellant resettling. Therefore, a series of tests were conducted in the Multi-purpose Hydrogen Test Bed (MHTB) of Marshall Space Flight Center (MSFC) in order to evaluate the effects of GHe pressurant on pressure control performance of a TVS with liquid hydrogen (LH2) and nitrogen (LN2) as the test liquids. The TVS used in these test series consists of a recirculation pump, Joule-Thomson (J-T) expansion valve, and a parallel flow concentric tube heat exchanger combined with a longitudinal spray bar. Using a small amount of liquid extracted from the tank recirculation line, passing it through the J-T valve, and then through the heat exchanger, thermal energy is extracted from the bulk liquid and ullage thereby enabling pressure control. The LH2/GHe tests were performed at fill levels of 90%, 50%, and 25% and LN2/GHe tests were conducted at fill levels of 50% and 25%. Moreover, each test was conducted with a specified tank ullage pressure control band. A one-dimensional TVS performance program was used to analyze and correlate the test data. Predictions and comparisons with test data of ullage pressure and temperature and bulk liquid saturation pressure and temperature with test data are presented.

  20. Orion ECLSS/Suit System Intermediate Pressure Integrated Suit Test

    NASA Technical Reports Server (NTRS)

    Barido, Richard A.

    2014-01-01

    The Intermediate Pressure Integrated Suit Test (IPIST) phase of the integrated system testing of the Orion Vehicle Atmosphere Revitalization System (ARS) technology was conducted for the Multipurpose Crew Vehicle (MPCV) Program within the National Aeronautics and Space Administration (NASA) Exploration Systems Mission Directorate. This test was performed in the eleven-foot human-rated vacuum chamber at the NASA Johnson Space Center by the Crew and Thermal Systems Division. This testing is the second phase of suit loop testing to demonstrate the viability of the Environmental Control and Life Support System (ECLSS) being developed for Orion. The IPIST configuration consisted of development hardware that included the CAMRAS, air revitalization loop fan and suit loop regulator. Two test subjects were in pressure suits at varying suit pressures. Follow-on testing, to be conducted in 2014, will utilize the same hardware with human test subjects in pressure suits at vacuum. This paper will discuss the results and findings of IPIST and will also discuss future testing.

  1. Three-Dimensional Digital Image Correlation of a Composite Overwrapped Pressure Vessel During Hydrostatic Pressure Tests

    NASA Technical Reports Server (NTRS)

    Revilock, Duane M., Jr.; Thesken, John C.; Schmidt, Timothy E.

    2007-01-01

    Ambient temperature hydrostatic pressurization tests were conducted on a composite overwrapped pressure vessel (COPV) to understand the fiber stresses in COPV components. Two three-dimensional digital image correlation systems with high speed cameras were used in the evaluation to provide full field displacement and strain data for each pressurization test. A few of the key findings will be discussed including how the principal strains provided better insight into system behavior than traditional gauges, a high localized strain that was measured where gages were not present and the challenges of measuring curved surfaces with the use of a 1.25 in. thick layered polycarbonate panel that protected the cameras.

  2. How to pressurize autoclaves for corrosion testing under carbon dioxide and hydrogen sulfide pressure

    SciTech Connect

    Crolet, J.L.; Bonis, M.R.

    2000-02-01

    All the methods presently used for pressurizing autoclaves have advantages and disadvantages. Pressurizing with pure gases is undoubtedly the surest method, since it is insensitive to the autoclave filling rate, and the influence of temperature stability readily can be controlled. The only limitation is the impossibility of accurately reproducing very low hydrogen sulfide (H{sub 2}S) partial pressures (<30 mbar) at high temperatures (>150 C). Conventional pressurizing with gas mixtures is not at all practical, since it demands either excessively large autoclaves or the bubbling of prohibitive volumes of gas. To overcome these fundamental difficulties, alternative methods are proposed, such as high-temperature bubbling using a cooled reflux condenser or presaturation of the autoclave at 60 C at a fraction of the test pressure, enabling the latter to be attained during subsequent heating by the natural increase in pressure with temperature.

  3. 49 CFR 178.605 - Hydrostatic pressure test.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 3 2014-10-01 2014-10-01 false Hydrostatic pressure test. 178.605 Section 178.605 Transportation Other Regulations Relating to Transportation (Continued) PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) SPECIFICATIONS FOR PACKAGINGS Testing of Non-bulk Packagings and Packages...

  4. Ion engine endurance testing at high background pressures

    NASA Technical Reports Server (NTRS)

    Brophy, John R.; Pless, Lewis C.; Garner, Charles E.

    1992-01-01

    Ion engine endurance testing at vacuum chamber pressures in the low 10 exp -3 Pa range is enabled through the use of a three-grid accelerator system with the decelerator grid biased 50 to 100 volts negative of neutralizer cathode potential. The negative decelerator grid serves to collect the facility induced charge exchange ion current which normally results in rapid erosion of the accelerator grid during testing at elevated vacuum chamber pressures. This screen, accelerator, negative decelerator (SAND) grid configuration enables an order of magnitude reduction in vacuum chamber pumping speeds relative to that required for endurance testing of ion engines with conventional two-grid accelerator systems. A 900-hr test of a 30-cm diameter engine at 6.5 kW and a tank pressure of 3.7 x 10 exp -3 Pa was performed to test the feasibility of the three-grid SAND accelerator system technology. Grid erosion rates from this test are compared to those from a 200-hr test performed with the same discharge chamber, in the same test facility, and at the same background pressure with a conventional two grid accelerator system. The SAND optics resulted in greater than a factor of 100 reduction in accelerator grid erosion rate relative to the two-grid system.

  5. 33 CFR 159.111 - Pressure and vacuum pulse test.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 2 2013-07-01 2013-07-01 false Pressure and vacuum pulse test. 159.111 Section 159.111 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY... vacuum pulse test. Liquid retention components of the device with manufacturer specified...

  6. Ion engine endurance testing at high background pressures

    NASA Astrophysics Data System (ADS)

    Brophy, John R.; Pless, Lewis C.; Garner, Charles E.

    1992-07-01

    Ion engine endurance testing at vacuum chamber pressures in the low 10 exp -3 Pa range is enabled through the use of a three-grid accelerator system with the decelerator grid biased 50 to 100 volts negative of neutralizer cathode potential. The negative decelerator grid serves to collect the facility induced charge exchange ion current which normally results in rapid erosion of the accelerator grid during testing at elevated vacuum chamber pressures. This screen, accelerator, negative decelerator (SAND) grid configuration enables an order of magnitude reduction in vacuum chamber pumping speeds relative to that required for endurance testing of ion engines with conventional two-grid accelerator systems. A 900-hr test of a 30-cm diameter engine at 6.5 kW and a tank pressure of 3.7 x 10 exp -3 Pa was performed to test the feasibility of the three-grid SAND accelerator system technology. Grid erosion rates from this test are compared to those from a 200-hr test performed with the same discharge chamber, in the same test facility, and at the same background pressure with a conventional two grid accelerator system. The SAND optics resulted in greater than a factor of 100 reduction in accelerator grid erosion rate relative to the two-grid system.

  7. Fan Noise Source Diagnostic Test: Vane Unsteady Pressure Results

    NASA Technical Reports Server (NTRS)

    Envia, Edmane

    2002-01-01

    To investigate the nature of fan outlet guide vane pressure fluctuations and their link to rotor-stator interaction noise, time histories of vane fluctuating pressures were digitally acquired as part of the Fan Noise Source Diagnostic Test. Vane unsteady pressures were measured at seven fan tip speeds for both a radial and a swept vane configuration. Using time-domain averaging and spectral analysis, the blade passing frequency (BPF) harmonic and broadband contents of the vane pressures were individually analyzed. Significant Sound Pressure Level (SPL) reductions were observed for the swept vane relative to the radial vane for the BPF harmonics of vane pressure, but vane broadband reductions due to sweep turned out to be much smaller especially on an average basis. Cross-correlation analysis was used to establish the level of spatial coherence of broadband pressures between different locations on the vane and integral length scales of pressure fluctuations were estimated from these correlations. Two main results of this work are: (1) the average broadband level on the vane (in dB) increases linearly with the fan tip speed for both the radial and swept vanes, and (2) the broadband pressure distribution on the vane is nearly homogeneous and its integral length scale is a monotonically decreasing function of fan tip speed.

  8. Pressure inactivation of microorganisms at moderate temperatures

    NASA Astrophysics Data System (ADS)

    Butz, P.; Ludwig, H.

    1986-05-01

    The inactivation of bacteria, bacterial spores, yeasts and molds by high hydrostatic pressure was investigated over a pressure range up to 3000 bar. Survival curves were measured as a function of temperature and pressure applied on the microorganisms. Conditions are looked for under which heat or radiation sensitive pharmaceutical preparations can be sterilized by high pressure treatment at moderate temperatures. All organisms tested can be inactivated in the range of 2000-2500 bar and between 40-60 degrees.

  9. Astronaut Joseph Kerwin test subject Lower Body Negative Pressure experiment

    NASA Technical Reports Server (NTRS)

    1973-01-01

    Scientist-Astronaut Joseph P. Kerwin, Skylab 2 science pilot, serves as test subject for the Lower Body Negative Pressure Experiment. Astronaut Paul J. Weitz, Skylab 2 pilot, assists Kerwin with the blood pressure cuff. They are in the experiment and work area of the Orbital Workshop crew quarters of the Skylab 1 and 2 space station cluster in Earth orbit. Kerwin is lying in the lower body negative pressure device. The purpose of the M092 experiment is to provide information concerning the time course of cardiovascular adaptation during flight, and to provide inflight data for predicting the degree of orthostatic intolerance and impairment of physical capacity to be expected upon return to Earth environment. The data collected in support of M092 are blood pressure, heart rate, body temperature, vectorcardiogram, LBNPD pressure, leg volume changes, and body weight.

  10. Static pressure orifice system testing method and apparatus

    NASA Technical Reports Server (NTRS)

    Culotta, R. F.; Posey, D. L. (Inventor)

    1980-01-01

    A method and apparatus are presented for pressure testing the static pressure orifices and associated connections used in wind tunnels. A cylindrical module, having in one end an open hemispherical calibration pressure chamber separated from and surrounded by an annular vacuum chamber is placed over the orifice of the system to be tested. O-rings ensure seating and a vacuum seal between the chambered end of the module and the surface around the orifice: one O-ring separates the outer chamber from the outside environment. Ports lead from each of the chambers out the other end of the module to tubes connected to a control box consisting of calibration pressure and vacuum supply lines, bleeder valves, and gauges.

  11. Composite Overwrapped Pressure Vessel (COPV) Stress Rupture Testing

    NASA Technical Reports Server (NTRS)

    Greene, Nathanael J.; Saulsberry, Regor L.; Leifeste, Mark R.; Yoder, Tommy B.; Keddy, Chris P.; Forth, Scott C.; Russell, Rick W.

    2010-01-01

    This paper reports stress rupture testing of Kevlar(TradeMark) composite overwrapped pressure vessels (COPVs) at NASA White Sands Test Facility. This 6-year test program was part of the larger effort to predict and extend the lifetime of flight vessels. Tests were performed to characterize control parameters for stress rupture testing, and vessel life was predicted by statistical modeling. One highly instrumented 102-cm (40-in.) diameter Kevlar(TradeMark) COPV was tested to failure (burst) as a single-point model verification. Significant data were generated that will enhance development of improved NDE methods and predictive modeling techniques, and thus better address stress rupture and other composite durability concerns that affect pressure vessel safety, reliability and mission assurance.

  12. Composite Overwrapped Pressure Vessel(COPV) Stress Rupture Testing

    NASA Astrophysics Data System (ADS)

    Greene, Nathanael J.; Saulsberry, Regor L.; Leifeste, Mark, R.; Yoder, Tommy B.; Keddy, Chris P.; Forth, Scott C.; Russell, Rick W.

    2010-09-01

    This paper reports stress rupture testing of Kevlar® composite overwrapped pressure vessels(COPVs) at NASA White Sands Test Facility. This 6-year test program was part of the larger effort to predict and extend the lifetime of flight vessels. Tests were performed to characterize control parameters for stress rupture testing, and vessel life was predicted by statistical modeling. One highly instrumented 102-cm(40-in.) diameter Kevlar® COPV was tested to failure(burst) as a single-point model verification. Significant data were generated that will enhance development of improved NDE methods and predictive modeling techniques, and thus better address stress rupture and other composite durability concerns that affect pressure vessel safety, reliability and mission assurance.

  13. Leaky guided waves in generic bars: Numerical prediction and experimental validation by means of ultrasonic underwater testing

    SciTech Connect

    Mazzotti, Matteo; Bartoli, Ivan; Marzani, Alessandro

    2014-02-18

    Guided Ultrasonic Waves (GUWs) are used in several industrial and civil applications for the non-destructive tests and inspection of mechanical waveguides immersed in fluids. As well known, the impedance mismatch at the fluid-structure interface causes the bulk waves traveling inside the waveguide to be partially refracted in the surrounding fluid. The leakage of bulk waves involves continuous energy radiation along the propagation direction, resulting in high attenuation rates and, consequently, reduced inspection ranges. In this work, the dispersion behaviour of leaky guided waves that propagate in immersed waveguides of general cross-section is investigated. To this end, a Semi-Analytical Finite Element (SAFE) method coupled with a 2.5D Boundary Element method (BEM) is used to extract the wave dispersion equation. The proposed formulation avoids the well known limitations of analytical methods in treating complex geometries as well as those of Finite Element-based methods in representing propagation processes in unbounded domains. Numerical and experimental results are presented, in which the dispersion curves are extracted for different bars of arbitrary shape immersed in water. The results obtained in this paper can be useful for the design of testing conditions in practical applications and to tune experimental set up.

  14. Strain localization during tensile Hopkinson bar testing of commercially pure titanium and Ti6Al4V titanium alloy

    NASA Astrophysics Data System (ADS)

    Moćko, Wojciech; Kruszka, Leopold; Brodecki, Adam

    2015-09-01

    The goal of the analysis was to determine the strain localization for various specimen shapes (type A and type B according to PN-EN ISO 26203-1 standard) and different loading conditions, i.e. quasi- static and dynamic. Commercially pure titanium (Grade 2) and titanium alloy Ti6Al4V (Grade 5) were selected for the tests. Tensile loadings were applied out using servo-hydraulic testing machine and tensile Hopkinson bar with pre-tension. The results were recorded using ARAMIS system cameras and fast camera Phantom V1210, respectively at quasi-static and dynamic loading conditions. Further, specimens outline was determined on the basis of video data using TEMA MOTION software. The strain distribution on the specimen surface was estimated using digital image correlation method. The larger radius present in the specimen of type B in comparison to specimen of type A, results in slight increase of the elongation for commercially pure titanium at both quasi-static and dynamic loading conditions. However this effect disappears for Ti6Al4V alloy. The increase of the elongation corresponds to the stronger necking effect. Material softening due to increase of temperature induced by plastic work was observed at dynamic loading conditions. Moreover lower elongation at fracture point was found at high strain rates for both materials.

  15. Composite Overwrapped Pressure Vessels (COPV) Stress Rupture Test

    NASA Technical Reports Server (NTRS)

    Russell, Richard; Flynn, Howard; Forth, Scott; Greene, Nathanael; Kezian, Michael; Varanauski, Don; Yoder, Tommy; Woodworth, Warren

    2009-01-01

    One of the major concerns for the aging Space Shuttle fleet is the stress rupture life of composite overwrapped pressure vessels (COPVs). Stress rupture life of a COPV has been defined as the minimum time during which the composite maintains structural integrity considering the combined effects of stress levels and time. To assist in the evaluation of the aging COPVs in the Orbiter fleet an analytical reliability model was developed. The actual data used to construct this model was from testing of COPVs constructed of similar, but not exactly same materials and pressure cycles as used on Orbiter vessels. Since no actual Orbiter COPV stress rupture data exists the Space Shuttle Program decided to run a stress rupture test to compare to model predictions. Due to availability of spares, the testing was unfortunately limited to one 40" vessel. The stress rupture test was performed at maximum operating pressure at an elevated temperature to accelerate aging. The test was performed in two phases. The first phase, 130 F, a moderately accelerated test designed to achieve the midpoint of the model predicted point reliability. The more aggressive second phase, performed at 160 F was designed to determine if the test article will exceed the 95% confidence interval of the model. This paper will discuss the results of this test, it's implications and possible follow-on testing.

  16. Lepton Universality Test in Upsilon(1S) Decays at BaBar

    SciTech Connect

    Guido, Elisa; /Genoa U. /INFN, Genoa

    2012-04-10

    Using a sample of 122 million {Upsilon}(3S) decays collected with the BABAR detector at the PEP-II asymmetric energy collider at the SLAC National Accelerator Laboratory, we measure the ratio R{sub {tau}{mu}} = BR({Upsilon}(1S) {yields} {tau}{sup +}{tau}{sup -})/BR({Upsilon}(1S) {yields} {mu}{sup +}{mu}{sup -}); the measurement is intended as a test of lepton universality and as a possible search for a light pseudoscalar Higgs boson in Next to Minimal Supersymmetric Standard Model (NMSSM) scenarios. Such a boson could appear in a deviation of the ratio R{sub {tau}{mu}} from the Standard Model expectation, that is 1, except for small lepton mass corrections. The analysis exploits the decays {Upsilon}(3S) {yields} {Upsilon}(1S){pi}{sup +}{pi}{sup -}, {Upsilon}(1S) {yields} l{sup +}l{sup -}, where l = {mu},{tau}.

  17. Terahertz NDE of Stressed Composite Overwrapped Pressure Vessels - Initial Testing

    NASA Technical Reports Server (NTRS)

    Madaras, Eric I.; Seebo, Jeffrey P.; Anatasi, Robert F.

    2009-01-01

    Terahertz radiation nondestructive evaluation was applied to a set of Kevlar composite overwrapped pressure vessel bottles that had undergone a series of thermal and pressure tests to simulate stress rupture effects. The bottles in these nondestructive evaluation tests were bottles that had not ruptured but had survived various times at the elevated load and temperature levels. Some of the bottles showed evidence of minor composite failures. The terahertz radiation did detect visible surface flaws, but did not detect any internal chemical or material degradation of the thin overwraps.

  18. Dark Matter Trapping by Stellar Bars: The Shadow Bar

    NASA Astrophysics Data System (ADS)

    Petersen, Michael S.; Weinberg, Martin D.; Katz, Neal

    2016-09-01

    We investigate the complex interactions between the stellar disc and the dark-matter halo during bar formation and evolution using N-body simulations with fine temporal resolution and optimally chosen spatial resolution. We find that the forming stellar bar traps dark matter in the vicinity of the stellar bar into bar-supporting orbits. We call this feature the shadow bar. The shadow bar modifies both the location and magnitude of the angular momentum transfer between the disc and dark matter halo and adds 10 per cent to the mass of the stellar bar over 4 Gyr. The shadow bar is potentially observable by its density and velocity signature in spheroid stars and by direct dark matter detection experiments. Numerical tests demonstrate that the shadow bar can diminish the rate of angular momentum transport from the bar to the dark matter halo by more than a factor of three over the rate predicted by dynamical friction with an untrapped dark halo, and thus provides a possible physical explanation for the observed prevalence of fast bars in nature.

  19. Test of Lepton Universality in Upsilon(1S) Decays at BaBar

    SciTech Connect

    del Amo Sanchez, P.; Lees, J.P.; Poireau, V.; Prencipe, E.; Tisserand, V.; Garra Tico, J.; Grauges, E.; Martinelli, M.; Palano, A.; Pappagallo, M.; Eigen, G.; Stugu, B.; Sun, L.; Battaglia, M.; Brown, David Nathan; Hooberman, B.; Kerth, L.T.; Kolomensky, Yu.G.; Lynch, G.; Osipenkov, I.L.; Tanabe, T.; /more authors..

    2010-06-07

    The ratio R{sub {tau}{mu}}({Upsilon}(1S))={Lambda}{sub {Upsilon}(1S){yields}{tau}{sup +}{tau}{sup -}}/{Lambda}{sub {Upsilon}(1S){yields}{mu}{sup +}{mu}{sup -}} is measured using a sample of (121.8 {+-} 1.2) x 10{sup 6}{Upsilon}(3S) events recorded by the BABAR detector. This measurement is intended as a test of lepton universality and as a search for a possible light pseudoscalar Higgs boson. In the standard model (SM) this ratio is expected to be close to 1. Any significant deviations would violate lepton universality and could be introduced by the coupling to a light pseudoscalar Higgs boson. The analysis studies the decays {Upsilon}(3S) {yields} {Upsilon}(1S){sub {pi}{sup +}{pi}{sup -}}, {Upsilon}(1S) {yields} {ell}{sup +}{ell}{sup -}, where l = {mu}, {tau}. The result, R{sub {tau}{mu}}({Upsilon}(1S))=1.005 {+-} 0.013(stat) {+-} 0.022(syst), shows no deviation from the expected SM value, while improving the precision with respect to previous measurements.

  20. Barred beaches

    NASA Astrophysics Data System (ADS)

    Wijnberg, Kathelijne M.; Kroon, Aart

    2002-11-01

    Seven different bar types are distinguished to provide a framework for comparing morphodynamic studies conducted in different areas. Five types occur in semiprotected or open coast settings, of which two are intertidal and three are subtidal. Two types occur in highly protected settings. The occurrence of a certain bar type is generally determined by the wave energy and tidal range, although the nearshore slope may also be a differentiating boundary condition. The theory behind the generation, evolution and decay of bars has evolved most for the subtidal bars in the semiprotected and open coast settings, for which three types of competing mechanisms have been formulated (breakpoint, infragravity waves, self-organisational). Most research has focused on these processes on the time scale of storm events and post-storm recovery. However, to understand the longer-term behavior of bar systems, knowledge of the role of relaxation time and morphologic feedback is needed as well. At present, such knowledge is very limited. We think it can best be obtained from the analysis of long time series of morphology and forcing conditions, rather than from intensive field experiments. In case of a feedback-dominated response (self-organisational), we expect to find no correlation between the time series of external forcing and the morphologic response. In case of a relaxation time-dominated response, we do expect to find such a correlation, albeit filtered. This discussion is illustrated by a case study of the Dutch coast.

  1. Design and testing of high-pressure railguns and projectiles

    SciTech Connect

    Peterson, D.R.; Fowler, C.M.

    1984-03-01

    The results of high-pressure tests of four railgun designs and four projectile types are presented. All tests were conducted at the Los Alamos explosive magnetic-flux compression facility in Ancho Canyon. The data suggest that the high-strength projectiles have lower resistance to acceleration than the lowstrength projectiles, which expand against the bore during acceleration. The railguns were powered by explosive magneticflux compression generators. Calculations to predict railgun and power supply performance were performed by Kerrisk.

  2. Design and testing of high-pressure railguns and projectiles

    SciTech Connect

    Peterson, D.R.; Fowler, C.M.; Cummings, C.E.; Kerrisk, J.F.; Parker, J.V.; Marsh, S.P.; Adams, D.F.

    1983-01-01

    The results of high-pressure tests of four railgun designs and four projectile types are presented. All tests were conducted at the Los Alamos explosive magnetic-flux compression facility in Ancho Canyon. The data suggest that the high-strength projectiles have lower resistance to acceleration than the low-strength projectiles, which expand against the bore during acceleration. The railguns were powered by explosive magnetic-flux compression generators. Calculations to predict railgun and power supply performance were performed.

  3. Pressure-Sensitive Paints Advance Rotorcraft Design Testing

    NASA Technical Reports Server (NTRS)

    2013-01-01

    The rotors of certain helicopters can spin at speeds as high as 500 revolutions per minute. As the blades slice through the air, they flex, moving into the wind and back out, experiencing pressure changes on the order of thousands of times a second and even higher. All of this makes acquiring a true understanding of rotorcraft aerodynamics a difficult task. A traditional means of acquiring aerodynamic data is to conduct wind tunnel tests using a vehicle model outfitted with pressure taps and other sensors. These sensors add significant costs to wind tunnel testing while only providing measurements at discrete locations on the model's surface. In addition, standard sensor solutions do not work for pulling data from a rotor in motion. "Typical static pressure instrumentation can't handle that," explains Neal Watkins, electronics engineer in Langley Research Center s Advanced Sensing and Optical Measurement Branch. "There are dynamic pressure taps, but your costs go up by a factor of five to ten if you use those. In addition, recovery of the pressure tap readings is accomplished through slip rings, which allow only a limited amount of sensors and can require significant maintenance throughout a typical rotor test." One alternative to sensor-based wind tunnel testing is pressure sensitive paint (PSP). A coating of a specialized paint containing luminescent material is applied to the model. When exposed to an LED or laser light source, the material glows. The glowing material tends to be reactive to oxygen, explains Watkins, which causes the glow to diminish. The more oxygen that is present (or the more air present, since oxygen exists in a fixed proportion in air), the less the painted surface glows. Imaged with a camera, the areas experiencing greater air pressure show up darker than areas of less pressure. "The paint allows for a global pressure map as opposed to specific points," says Watkins. With PSP, each pixel recorded by the camera becomes an optical pressure

  4. The influence of intraocular pressure and air jet pressure on corneal contactless tonometry tests.

    PubMed

    Simonini, Irene; Pandolfi, Anna

    2016-05-01

    The air puff is a dynamic contactless tonometer test used in ophthalmology clinical practice to assess the biomechanical properties of the human cornea and the intraocular pressure due to the filling fluids of the eye. The test is controversial, since the dynamic response of the cornea is governed by the interaction of several factors which cannot be discerned within a single measurement. In this study we describe a numerical model of the air puff tests, and perform a parametric analysis on the major action parameters (jet pressure and intraocular pressure) to assess their relevance on the mechanical response of a patient-specific cornea. The particular cornea considered here has been treated with laser reprofiling to correct myopia, and the parametric study has been conducted on both the preoperative and postoperative geometries. The material properties of the cornea have been obtained by means of an identification procedure that compares the static biomechanical response of preoperative and postoperative corneas under the physiological IOP. The parametric study on the intraocular pressure suggests that the displacement of the cornea׳s apex can be a reliable indicator for tonometry, and the one on the air jet pressure predicts the outcomes of two or more distinct measurements on the same cornea, which can be used in inverse procedures to estimate the material properties of the tissue. PMID:26282384

  5. 49 CFR 178.814 - Hydrostatic pressure test.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... pressure (pressure in the IBC above ambient atmospheric pressure) measured in the IBC at 55 °C (131 °F... pressure of the hazardous material plus atmospheric pressure) is used, 1.5 multiplied by the vapor pressure... pressure (vapor pressure of the hazardous material plus atmospheric pressure) is used, 1.75......

  6. 49 CFR 178.814 - Hydrostatic pressure test.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... pressure (pressure in the IBC above ambient atmospheric pressure) measured in the IBC at 55 °C (131 °F... pressure of the hazardous material plus atmospheric pressure) is used, 1.5 multiplied by the vapor pressure... pressure (vapor pressure of the hazardous material plus atmospheric pressure) is used, 1.75......

  7. 49 CFR 178.814 - Hydrostatic pressure test.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... pressure (pressure in the IBC above ambient atmospheric pressure) measured in the IBC at 55 °C (131 °F... pressure of the hazardous material plus atmospheric pressure) is used, 1.5 multiplied by the vapor pressure... pressure (vapor pressure of the hazardous material plus atmospheric pressure) is used, 1.75......

  8. 49 CFR 178.814 - Hydrostatic pressure test.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... pressure (pressure in the IBC above ambient atmospheric pressure) measured in the IBC at 55 °C (131 °F... pressure of the hazardous material plus atmospheric pressure) is used, 1.5 multiplied by the vapor pressure... pressure (vapor pressure of the hazardous material plus atmospheric pressure) is used, 1.75......

  9. Acceptance test procedure for High Pressure Water Jet System

    SciTech Connect

    Crystal, J.B.

    1995-05-30

    The overall objective of the acceptance test is to demonstrate a combined system. This includes associated tools and equipment necessary to perform cleaning in the 105 K East Basin (KE) for achieving optimum reduction in the level of contamination/dose rate on canisters prior to removal from the KE Basin and subsequent packaging for disposal. Acceptance tests shall include necessary hardware to achieve acceptance of the cleaning phase of canisters. This acceptance test procedure will define the acceptance testing criteria of the high pressure water jet cleaning fixture. The focus of this procedure will be to provide guidelines and instructions to control, evaluate and document the acceptance testing for cleaning effectiveness and method(s) of removing the contaminated surface layer from the canister presently identified in KE Basin. Additionally, the desired result of the acceptance test will be to deliver to K Basins a thoroughly tested and proven system for underwater decontamination and dose reduction. This report discusses the acceptance test procedure for the High Pressure Water Jet.

  10. High Pressure Composite Overwrapped Pressure Vessel (COPV) Development Tests at Cryogenic Temperatures

    NASA Technical Reports Server (NTRS)

    Ray, David M.; Greene, Nathanael J.; Revilock, Duane; Sneddon, Kirk; Anselmo, Estelle

    2008-01-01

    Development tests were conducted to evaluate the performance of 2 COPV designs at cryogenic temperatures. This allows for risk reductions for critical components for a Gaseous Helium (GHe) Pressurization Subsystem for an Advanced Propulsion System (APS) which is being proposed for NASA s Constellation project and future exploration missions. It is considered an advanced system since it uses Liquid Methane (LCH4) as the fuel and Liquid Oxygen (LO2) as the oxidizer for the propellant combination mixture. To avoid heating of the propellants to prevent boil-off, the GHe will be stored at subcooled temperatures equivalent to the LO2 temperature. Another advantage of storing GHe at cryogenic temperatures is that more mass of the pressurized GHe can be charged in to a vessel with a smaller volume, hence a smaller COPV, and this creates a significant weight savings versus gases at ambient temperatures. The major challenge of this test plan is to verify that a COPV can safely be used for spacecraft applications to store GHe at a Maximum Operating Pressure (MOP) of 4,500 psig at 140R to 160R (-320 F to -300 F). The COPVs for these tests were provided by ARDE , Inc. who developed a resin system to use at cryogenic conditions and has the capabilities to perform high pressure testing with LN2.

  11. The Destructive High Pressure Tests of Cylindrical Shells

    SciTech Connect

    Yasumi Kitajima; Satoru Shibata

    2002-07-01

    We conducted the limit state tests of cylindrical shells to establish criteria for the occurrence of steel wall/liner tearing in the reactor containment vessels (such as Steel Containment Vessels (SCV), Prestressed Concrete Containment Vessels (PCCV) and Reinforced Concrete Containment Vessels (RCCV)) under the limit state pressure. In the tests, precisely manufactured cylindrical shell vessels (about 800 mm in height and 300 mm in diameter) were pressurized to the failure using water. We also conducted the finite element analyses. The conclusions are as follows: 1. We obtained good agreement (within 2-3%) between the tests and the analyses in structural behavior such as internal pressure loading vs. displacement and strain to the failure. However, in the case of the test piece which included weld line on the cylindrical wall, the difference between the tests and the analyses was larger (about 1.5 times) than the rest. 2. The localized strains began to increase when radial strains in general structure reached 5-10%. We are intended to apply these results to the finite element analyses and the integrity evaluation of containment vessels (SCV, PCCV and RCCV). (authors)

  12. Techniques for embedding instrumentation in pressure vessel test articles

    NASA Astrophysics Data System (ADS)

    Cornelius, Michael

    2006-05-01

    Many interesting structural and thermal events occur in materials that are housed within a surrounding pressure vessel. In order to measure the environment during these events and explore their causes instrumentation must be installed on or in the material. Transducers can be selected that are small enough to be embedded within the test material but these instruments must interface with an external system in order to apply excitation voltages and output the desired data. The methods for installing the instrumentation and creating an interface are complicated when the material is located in a case or housing containing high pressures and hot gases. Installation techniques for overcoming some of these difficulties were developed while testing a series of small-scale solid propellant and hybrid rocket motors at Marshall Space Flight Center. These techniques have potential applications in other test articles where data are acquired from materials that require containment due to the severe environment encountered during the test process. This severe environment could include high pressure, hot gases, or ionized atmospheres. The development of these techniques, problems encountered, and the lessons learned from the ongoing testing process are summarized.

  13. Techniques for Embedding Instrumentation in Pressure Vessel Test Articles

    NASA Technical Reports Server (NTRS)

    Cornelius, Michael

    2006-01-01

    Many interesting structural and thermal events occur in materials that are housed within a surrounding pressure vessel. In order to measure the environment during these events and explore their causes instrumentation must be installed on or in the material. Transducers can be selected that are small enough to be embedded within the test material but these instruments must interface with an external system in order to apply excitation voltages and output the desired data. The methods for installing the instrumentation and creating an interface are complicated when the material is located in a case or housing containing high pressures and hot gases. Installation techniques for overcoming some of these difficulties were developed while testing a series of small-scale solid propellant and hybrid rocket motors at Marshall Space Flight Center. These techniques have potential applications in other test articles where data are acquired from materials that require containment due to the severe environment encountered during the test process. This severe environment could include high pressure, hot gases, or ionized atmospheres. The development of these techniques, problems encountered, and the lessons learned from the ongoing testing process are summarized.

  14. Pressure-interference testing of the Sumikawa geothermal field

    SciTech Connect

    Garg, S.K.; Pritchett, J.W.; Ariki, K.; Kawano, Y.

    1991-01-01

    Pressure interference tests have been used to determine the permeability structure of the Sumikawa reservoir. Interference tests between wells S-4 and KY-1 have indicated the presence of a very high permeability (140 md) north-south channel in the altered andesite layer. Pressure buildup data from well SN-7D have provided indications of a high transmissivity (kh {approx} 18 darcy-meters) reservoir located in the granodiorite layer, lack of pressure response in nearby shutin Sumikawa wells implies that the reservoir penetrated by SN-7D is isolated from the shallower reservoir in the altered andesites. The ''altered andesite'' and the ''granodiorite'' formations constitute the principal geothermal aquifers at Sumikawa. Pressure interference tests (wells KY-1 and SB-2, and wells KY-2 and SB-3) have also confirmed the presence of moderately high transmissivity ({approx} 2 darcy-meters) dacitic layers in the ''marine-volcanic complex'' formation. Because of its low vertical permeability, the ''marine volcanic complex'' formation constitutes an attractive target for the reinjection of waste geothermal fluids.

  15. Hydrogen gas embrittlement and the disc pressure test

    NASA Technical Reports Server (NTRS)

    Bachelet, E. J.; Troiano, A. R.

    1973-01-01

    A disc pressure test has been used to study the influenced of a hydrogen gas environment on the mechanical properties of three high strength superalloys, Inconel 718, L-605 and A-286, in static and dynamic conditions. The influence of the hydrogen pressure, loading rate, temperature, mechanical and thermal fatigue has investigated. The permeation characteristics of Inconel 718 have been determined in collaboration with the French AEC. The results complemented by a fractographic study are consistent either with a stress-sorption or with an internal embrittlement type of mechanism.

  16. Design and testing of high-pressure railguns and projectiles

    NASA Technical Reports Server (NTRS)

    Peterson, D. R.; Fowler, C. M.; Cummings, C. E.; Kerrisk, J. F.; Parker, J. V.; Marsh, S. P.; Adams, D. F.

    1984-01-01

    Attention is given to the results of high-pressure tests involving four railgun designs and four projectile types. Explosive magnetic-flux compression generators were employed to power the railguns. On the basis of the experimental data, it appears that the high-strength projectiles have lower resistance to acceleration than low-strength projectiles, which expand against the bore during acceleration. While confined in the bore, polycarbonate projectiles can be subjected to pressures as high as 1.3 GPa without shattering. In multishot railguns, it is important to prevent an accumulation of sooty material from the plasma armature in railgun seams.

  17. Design and testing of high-pressure railguns and projectiles

    NASA Astrophysics Data System (ADS)

    Peterson, D. R.; Fowler, C. M.; Cummings, C. E.; Kerrisk, J. F.; Parker, J. V.; Marsh, S. P.; Adams, D. F.

    1984-03-01

    Attention is given to the results of high-pressure tests involving four railgun designs and four projectile types. Explosive magnetic-flux compression generators were employed to power the railguns. On the basis of the experimental data, it appears that the high-strength projectiles have lower resistance to acceleration than low-strength projectiles, which expand against the bore during acceleration. While confined in the bore, polycarbonate projectiles can be subjected to pressures as high as 1.3 GPa without shattering. In multishot railguns, it is important to prevent an accumulation of sooty material from the plasma armature in railgun seams.

  18. Development test procedure High Pressure Water Jet System

    SciTech Connect

    Crystal, J.B.

    1995-06-05

    Development testing will be performed on the water jet cleaning fixture to determine the most effective arrangement of water jet nozzles to remove contamination from the surfaces of canisters and other debris. The following debris may be stained with dye to simulate surface contaminates: Mark O, Mark I, and Mark II Fuel Storage Canisters (both stainless steel and aluminum), pipe of various size, (steel, stainless, carbon steel and aluminum). Carbon steel and stainless steel plate, channel, angle, I-beam and other surfaces, specifically based on the Scientific Ecology Group (SEG) inventory and observations of debris within the basin. Test procedure for developmental testing of High Pressure Water Jet System.

  19. 49 CFR 178.814 - Hydrostatic pressure test.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... following methods: (A) The gauge pressure (pressure in the IBC above ambient atmospheric pressure) measured...); (B) If absolute pressure (vapor pressure of the hazardous material plus atmospheric pressure) is used... atmospheric pressure) is used, 1.75 multiplied by the vapor pressure of the hazardous material at 50......

  20. Atmospheric pressure gas chromatography-time-of-flight-mass spectrometry (APGC-ToF-MS) for the determination of regulated and emerging contaminants in aqueous samples after stir bar sorptive extraction (SBSE).

    PubMed

    Pintado-Herrera, Marina G; González-Mazo, Eduardo; Lara-Martín, Pablo A

    2014-12-01

    This work presents the development, optimization and validation of a multi-residue method for the simultaneous determination of 102 contaminants, including fragrances, UV filters, repellents, endocrine disruptors, biocides, polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), and several types of pesticides in aqueous matrices. Water samples were processed using stir bar sorptive extraction (SBSE) after the optimization of several parameters: agitation time, ionic strength, presence of organic modifiers, pH, and volume of the derivatizing agent. Target compounds were extracted from the bars by liquid desorption (LD). Separation, identification and quantification of analytes were carried out by gas chromatography (GC) coupled to time-of-flight (ToF-MS) mass spectrometry. A new ionization source, atmospheric pressure gas chromatography (APGC), was tested. The optimized protocol showed acceptable recovery percentages (50-100%) and limits of detection below 1ngL(-1) for most of the compounds. Occurrence of 21 out of 102 analytes was confirmed in several environmental aquatic matrices, including seawater, sewage effluent, river water and groundwater. Non-target compounds such as organophosphorus flame retardants were also identified in real samples by accurate mass measurement of their molecular ions using GC-APGC-ToF-MS. To the best of our knowledge, this is the first time that this technique has been applied for the analysis of contaminants in aquatic systems. By employing lower energy than the more widely used electron impact ionization (EI), AGPC provides significant advantages over EI for those substances very susceptible to high fragmentation (e.g., fragrances, pyrethroids). PMID:25440658

  1. Surface fatigue life of carburized and hardened M50NiL and AISI 9310 spur gears and rolling-contact test bars

    NASA Technical Reports Server (NTRS)

    Townsend, Dennis P.; Bamberger, Eric N.

    1989-01-01

    Spur gear endurance tests and rolling-element surface tests were conducted to investigate vacuum-induction-melted, vacuum-arc-melted (VIM-VAR) M50NiL steel for use as a gear steel in advanced aircraft applications, to determine its endurance characteristics, and to compare the results with those for standard VAR and VIM-VAR AISI 9310 gear material. Tests were conducted with spur gears and rolling-contact bars manufactured from VIM-VAR M50NiL and VAR and VIM-VAR AISI 9310. The gear pitch diameter was 8.9 cm (3.5 in.). Gear test conditions were an inlet oil temperature of 320 K (116 F), and outlet oil temperature of 350 K (170 F), a maximum Hertz stress of 1.71 GPa (248 ksi), and a speed of 10,000 rpm. Bench rolling-element fatigue tests were conducted at ambient temperatures with a bar speed of 12,500 rpm and a maximum Hertz stress of 4.83 GPA (700 ksi). The VIM-VAR M50NiL gears had a surface fatigue life that was 4.5 and 11.5 times that for VIM-VAR and VAR AISI 9310 gears, respectively. The surface fatigue life of the VIM-VAR M50NiL rolling-contact bars was 13.2 and 21.6 times that for the VIM-VAR and VAR AISI 9310, respectively. The VIM-VAR M50NiL material was shown to have good resistance to fracture through a fatigue spall and to have fatigue life far superior to that of both VIM-VAR and VAR AISI 9310 gears and rolling-contact bars.

  2. Barometric pressure transient testing applications at the Nevada Test Site: formation permeability analysis. Final report

    SciTech Connect

    Hanson, J.M.

    1984-12-01

    The report evaluates previous investigations of the gas permeability of the rock surrounding emplacement holes at the Nevada Test Site. The discussion sets the framework from which the present uncertainty in gas permeability can be overcome. The usefulness of the barometric pressure testing method has been established. Flow models were used to evaluate barometric pressure transients taken at NTS holes U2fe, U19ac and U20ai. 31 refs., 103 figs., 18 tabs. (ACR)

  3. MECHANICAL TESTING OF CARBON STEEL IN HIGH PRESSURE HYDROGEN

    SciTech Connect

    Duncan, A

    2006-05-11

    The methods and interim results from a testing program to quantify hydrogen effects on mechanical properties of carbon steel pipeline and pipeline weld materials are provided. The scope is carbon steels commonly used for natural gas pipelines in the United States that are candidates for hydrogen service in the hydrogen economy. The mechanical test results will be applied in future analyses to evaluate service life of the pipelines. The results are also envisioned to be part of the bases for construction codes and structural integrity demonstrations for hydrogen service pipeline and vessels. Tensile properties of one type of steel (A106 Grade B) in base metal, welded and heat affected zone conditions were tested at room temperature in air and high pressure (1500 psig) hydrogen. A general reduction in the materials ability to plastically deform was noted in this material when specimens were tested in 1500 psig hydrogen. Furthermore, the primary mode of fracture was changed from ductile rupture in air to cleavage with secondary tearing in hydrogen. The mechanical test program will continue with tests to quantify the fracture behavior in terms of J-R curves for these materials at air and hydrogen pressure conditions.

  4. Testing of fuel/oxidizer-rich, high-pressure preburners

    NASA Technical Reports Server (NTRS)

    Lawver, B. R.

    1982-01-01

    Results of an evaluation of high pressure combustion of fuel rich and oxidizer rich LOX/RP-1 propellants using 4.0 inch diameter prototype preburner injectors and chambers are presented. Testing covered a pressure range from 8.9 to 17.5 MN/square meters (1292 to 2540 psia). Fuel rich mixture ratios ranged from 0.238 to 0.367; oxidizer rich mixture ratios ranged from 27.2 to 47.5. Performance, gas temperature uniformity, and stability data for two fuel rich and two ozidizer rich preburner injectors are presented for a conventional like-on-like (LOL) design and a platelet design injector. Kinetically limited combustion is shown by the excellent agreement of measured fuel rich gas composition and C performance data with kinetic model predictions. The oxidizer rich test results support previous equilibrium combustion predictions.

  5. Multilayer Pressure Vessel Materials Testing and Analysis. Phase 1

    NASA Technical Reports Server (NTRS)

    Cardinal, Joseph W.; Popelar, Carl F.; Page, Richard A.

    2014-01-01

    To provide NASA a comprehensive suite of materials strength, fracture toughness and crack growth rate test results for use in remaining life calculations for aging multilayer pressure vessels, Southwest Research Institute (R) (SwRI) was contracted in two phases to obtain relevant material property data from a representative vessel. This report describes Phase 1 of this effort which includes a preliminary material property assessment as well as a fractographic, fracture mechanics and fatigue crack growth analyses of an induced flaw in the outer shell of a representative multilayer vessel that was subjected to cyclic pressure test. SwRI performed this Phase 1 effort under contract to the Digital Wave Corporation in support of their contract to Jacobs ATOM for the NASA Ames Research Center.

  6. 30 CFR 250.448 - What are the BOP pressure tests requirements?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... have approved those test pressures in your APD. (c) High pressure test for annular-type BOPs. The high... 30 Mineral Resources 2 2010-07-01 2010-07-01 false What are the BOP pressure tests requirements... Blowout Preventer (bop) System Requirements § 250.448 What are the BOP pressure tests requirements?...

  7. Identification of steel bars immersed in reinforced concrete based on experimental results of eddy current testing and artificial neural network analysis

    NASA Astrophysics Data System (ADS)

    de Alcantara, Naasson

    2013-03-01

    This paper presents an experimental research on the use of eddy current testing (ECT) and artificial neural networks (ANNs) in order to identify the gauge and position of steel bars immersed in concrete structures. The paper presents details of the ECT probe and concrete specimens constructed for the tests, and a study about the influence of the concrete on the values of measured voltages. After this, new measurements were done with a greater number of specimens, simulating a field condition and the results were used to generate training and validation vectors for multilayer perceptron ANNs. The results show a high percentage of correct identification with respect to both, the gauge of the bar and of the thickness of the concrete cover.

  8. Creep-rupture tests of internally pressurized Inconel 702 tubes

    NASA Technical Reports Server (NTRS)

    Gumto, K. H.

    1973-01-01

    Seamless Inconel 702 tubes with 0.375-in. outside diameter and 0.025-in. wall thickness were tested to failure at temperatures from 1390 to 1575 F and internal helium pressures from 700 to 1800 psi. Lifetimes ranged from 29 to 1561 hr. The creep-rupture strength of the tubes was about 70 percent lower than that of sheet specimens. Larson-Miller correlations and photomicrographs of some specimens are presented.

  9. TENSILE TESTING OF CARBON STEEL IN HIGH PRESSURE HYDROGEN

    SciTech Connect

    Duncan, A; Thad Adams, T; Ps Lam, P

    2007-05-02

    An infrastructure of new and existing pipelines and systems will be required to carry and to deliver hydrogen as an alternative energy source under the hydrogen economy. Carbon and low alloy steels of moderate strength are currently used in hydrogen delivery systems as well as in the existing natural gas systems. It is critical to understand the material response of these standard pipeline materials when they are subjected to pressurized hydrogen environments. The methods and results from a testing program to quantify hydrogen effects on mechanical properties of carbon steel pipeline and pipeline weld materials are provided. Tensile properties of one type of steel (A106 Grade B) in base metal, welded and heat affected zone conditions were tested at room temperature in air and high pressure (10.34 MPa or 1500 psig) hydrogen. A general reduction in the materials ability to plastically deform was noted in this material when specimens were tested in hydrogen. Furthermore, the primary mode of fracture was changed from ductile rupture in air to cleavage with secondary tearing in hydrogen. The mechanical test results will be applied in future analyses to evaluate service life of the pipelines. The results are also envisioned to be part of the bases for construction codes and structural integrity demonstrations for hydrogen service pipeline and vessels.

  10. Proposal for high pressure RF cavity test in the MTA

    SciTech Connect

    Yonehara, K.; /Fermilab

    2010-09-01

    In order to demonstrate the feasibility of high pressure hydrogen gas filled RF (HPRF) cavities for muon ionization cooling, an HPRF cavity must be tested with a high intensity charged beam. When an HPRF cavity is irradiated with an intense beam each incident particle generates about 1000 electrons and ions per cubic centimeter in a high pressure cavity via ionization. These ionization electrons are influenced by the RF field and the RF quality factor goes down. This Q factor reduction will be a problem with a multi bunch beam, e.g., a muon beam for a muon collider consists of a 12 to 20 bunch train beam with 5 ns timing gap. Thus, the RF field must recover in few nano seconds. We propose to use a 400 MeV proton beam in the MTA and measure a beam loading effect in the HPRF cavity and study the recovery mechanism of the RF field.

  11. Results from a 20 scintillator bar time-of-flight test system located inside the 1.4 T CDF solenoid

    NASA Astrophysics Data System (ADS)

    Ukegawa, F.; Heinrich, J. G.; Lockyer, N. S.; Long, O.; Kononenko, W.; Gao, T.; Newcomer, F. M.; Van Berg, R.; Kephart, R.; Mori, S.; Kondo, K.

    2000-01-01

    This paper reports on a test time-of-flight (TOF) system that operated in the Collider Detector at Fermilab (CDF) during pp¯ Tevatron collider operation at s=1.8 TeV in the fall 1995 running period. The TOF system consisted of 20 130×4×4 cm3 long Bicron BC408 scintillator bars, with each end of the bars fitted with a small compound parabolic concentrator and a 16-stage R5946 Hamamatsu fine-mesh photomultiplier. The electronics chain consisted of a custom designed preamplifier, constant fraction discriminator, and commercial TDC and ADC FASTBUS modules read out with the CDF data acquisition system. The counters were installed between the Central Tracking Chamber and the 1.4 T superconducting solenoid at a mean radius of 140 cm. We report a procedure for calculating the t0 time from all tracks in an event, the timing resolution, and the particle identification performance of this system.

  12. 49 CFR 179.500-16 - Tests of pressure relief devices.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Tests of pressure relief devices. 179.500-16...-113 and 107A) § 179.500-16 Tests of pressure relief devices. (a) Pressure relief valves shall be tested by air or gas before being put into service. Valve shall open at pressure not exceeding the...

  13. 49 CFR 179.500-16 - Tests of pressure relief devices.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 3 2013-10-01 2013-10-01 false Tests of pressure relief devices. 179.500-16... 107A) § 179.500-16 Tests of pressure relief devices. (a) Pressure relief valves shall be tested by air or gas before being put into service. Valve shall open at pressure not exceeding the marked...

  14. Numerical Modeling and Test Data Comparison of Propulsion Test Article Helium Pressurization System

    NASA Technical Reports Server (NTRS)

    Holt, Kimberly; Majumdar, Alok; Steadman, Todd; Hedayat, Ali; Fogle, Frank R. (Technical Monitor)

    2000-01-01

    A transient model of the propulsion test article (PTA) helium pressurization system was developed using the generalized fluid system simulation program (GFSSP). The model included pressurization lines from the facility interface to the engine purge interface and liquid oxygen (lox) and rocket propellant-1 (RP-1) tanks, the propellant tanks themselves including ullage space, and propellant feed lines to their respective pump interfaces. GFSSP's capability was extended to model a control valve to maintain ullage pressure within a specified limit and pressurization processes such as heat transfer between ullage gas, propellant, and the tank wall as well as conduction in the tank wall. The purpose of the model is to predict the flow system characteristics in the entire pressurization system during 80 sec of lower feed system priming, 420 sec of fuel and lox pump priming, and 150 sec of engine firing.

  15. CLOSEOUT REPORT FOR HYBRID SULFUR PRESSURIZED BUTTON CELL TEST FACILITY

    SciTech Connect

    Steeper, T.

    2010-09-15

    This document is the Close-Out Report for design and partial fabrication of the Pressurized Button Cell Test Facility at Savannah River National Laboratory (SRNL). This facility was planned to help develop the sulfur dioxide depolarized electrolyzer (SDE) that is a key component of the Hybrid Sulfur Cycle for generating hydrogen. The purpose of this report is to provide as much information as possible in case the decision is made to resume research. This report satisfies DOE Milestone M3GSR10VH030107.0. The HyS Cycle is a hybrid thermochemical cycle that may be used in conjunction with advanced nuclear reactors or centralized solar receivers to produce hydrogen by watersplitting. The HyS Cycle utilizes the high temperature (>800 C) thermal decomposition of sulfuric acid to produce oxygen and regenerate sulfur dioxide. The unique aspect of HyS is the generation of hydrogen in a water electrolyzer that is operated under conditions where dissolved sulfur dioxide depolarizes the anodic reaction, resulting in substantial voltage reduction. Low cell voltage is essential for both high thermodynamic efficiency and low hydrogen cost. Sulfur dioxide is oxidized at the anode, producing sulfuric acid that is sent to the high temperature acid decomposition portion of the cycle. Sulfur dioxide from the decomposer is cycled back to electrolyzers. The electrolyzer cell uses the membrane electrode assembly (MEA) concept. Anode and cathode are formed by spraying a catalyst, typically platinized carbon, on both sides of a Proton Exchange Membrane (PEM). SRNL has been testing SDEs for several years including an atmospheric pressure Button Cell electrolyzer (2 cm{sup 2} active area) and an elevated temperature/pressure Single Cell electrolyzer (54.8 cm{sup 2} active area). SRNL tested 37 MEAs in the Single Cell electrolyzer facility from June 2005 until June 2009, when funding was discontinued. An important result of the final months of testing was the development of a method that

  16. Measurement of hydrogen permeation through SUS 316L for pressures from 0.8 to 2.0 bar and thicknesses from 1 to 3 mm at 800°C

    NASA Astrophysics Data System (ADS)

    Lee, S. K.; Noh, S. J.; In, S. R.

    2012-07-01

    A detailed understanding of the permeation of hydrogen isotopes through structural materials is an important issue concerning the reliability, safety, fuelling and environmental impact of fusion power reactors. The permeation of hydrogen through SUS 316L stainless steel, which will be used in various parts of fusion power reactors, was investigated at an elevated temperature of 800 °C. From experiments at different hydrogen feed pressures of 0.8, 1.0, 1.5, and 2.0 bar with a 3-mm-thick membrane coupon, the hydrogen pressure exponent was determined, and the rate-limiting step for the permeation was determined to be bulk diffusion. From experiments using membranes of various thicknesses of 1, 2, and 3 mm at 1 bar, the effect of the membrane thickness on the hydrogen permeation was studied and discussed in relation to the bulk diffusion process. The results and the discussions for the hydrogen permeation experiments are presented here.

  17. External Pressure Testing of the 60-Watt Isotopic Heat Source

    SciTech Connect

    Frazier, T. A.; Christenbury, S. T.

    1995-03-15

    The purpose of this manual is to establish the capability of the IHS generator system to contain its radioisotopic source under an accident scenario in which the generator is deposited in the ocean at great depth. This procedure is to be used on assemblies designated to demonstrate the capability of the 60-watt IHS in external pressure environments. A qualified helium leak technician (NDE) performs evaluations during post test activities. Quality Engineering (QE) is present during testing to monitor activities. Testing involves a 60-watt IHS/Heater Head Assembly with the simulant yttria in place of the isotopic fuel. The standard length 0.094 inch diameter SST dowel pin is replaced with a longer pin to facilitate disassembly. The assembly is tested to 1000 atmospheres (-15,000 psi). It is then evaluated. If it shows no evidence of collapse, an additional test is conducted for information only. The Source Document is "Safety Test Program Plan for the 60-Watt Isotopic Heat Source (IHS)", TBE-32156-IHS-008 Issue

  18. Creep-rupture tests of internally pressurized Rene 41 tubes

    NASA Technical Reports Server (NTRS)

    Gumto, K. H.; Weiss, B.

    1972-01-01

    Weld-drawn tubes of Rene 41 with 0.935 centimeter outside diameter and 0.064 centimeter wall thickness were tested to failure at temperatures from 1117 to 1233 K and internal helium pressures from 5.5 to 12.4 meganewtons per square meter. Lifetimes ranged from 5 to 2065 hours. The creep-rupture strength of the tubes was 50 percent lower than that of unwelded, thick sheet specimens, and 20 percent lower than that of unwelded, thin sheet specimens. Larson-Miller correlations and photomicrographs of some specimens are presented.

  19. Solar Thermal Upper Stage Liquid Hydrogen Pressure Control Testing

    NASA Technical Reports Server (NTRS)

    Moore, J. D.; Otto, J. M.; Cody, J. C.; Hastings, L. J.; Bryant, C. B.; Gautney, T. T.

    2015-01-01

    High-energy cryogenic propellant is an essential element in future space exploration programs. Therefore, NASA and its industrial partners are committed to an advanced development/technology program that will broaden the experience base for the entire cryogenic fluid management community. Furthermore, the high cost of microgravity experiments has motivated NASA to establish government/aerospace industry teams to aggressively explore combinations of ground testing and analytical modeling to the greatest extent possible, thereby benefitting both industry and government entities. One such team consisting of ManTech SRS, Inc., Edwards Air Force Base, and Marshall Space Flight Center (MSFC) was formed to pursue a technology project designed to demonstrate technology readiness for an SRS liquid hydrogen (LH2) in-space propellant management concept. The subject testing was cooperatively performed June 21-30, 2000, through a partially reimbursable Space Act Agreement between SRS, MSFC, and the Air Force Research Laboratory. The joint statement of work used to guide the technical activity is presented in appendix A. The key elements of the SRS concept consisted of an LH2 storage and supply system that used all of the vented H2 for solar engine thrusting, accommodated pressure control without a thermodynamic vent system (TVS), and minimized or eliminated the need for a capillary liquid acquisition device (LAD). The strategy was to balance the LH2 storage tank pressure control requirements with the engine thrusting requirements to selectively provide either liquid or vapor H2 at a controlled rate to a solar thermal engine in the low-gravity environment of space operations. The overall test objective was to verify that the proposed concept could enable simultaneous control of LH2 tank pressure and feed system flow to the thruster without necessitating a TVS and a capillary LAD. The primary program objectives were designed to demonstrate technology readiness of the SRS concept

  20. Space Shuttle Main Engine instrumented High Pressure Oxidizer Turbopump technology test bed testing results summary

    NASA Technical Reports Server (NTRS)

    Koelbl, Mary E.

    1993-01-01

    This paper presents the test results from the Space Shuttle Main Engine (SSME) instrumented High Pressure Oxidizer Turbopump (HPOTP). The turbopump was tested on Engine 3001, a highly instrumented engine, in an effort to characterize the turbopump and the engine system. Seven tests, for a total duration of 766 seconds, were performed over a five month time period. The testing was performed at a wide variety of engine conditions. Changes in engine mixture ratio, power level, engine inlet oxidizer pressure, engine inlet fuel pressure, and engine start sequence were made. A discussion of all the HPOTP pressure and temperature data obtained are presented with comparisons to supporting analyses made where applicable. The effect of the various engine conditions on the measured data is addressed. This paper also discusses the challenges that were overcome to obtain the data. The significant instrumentation related problems encountered during the design, fabrication, and testing of this turbopump are summarized. Only those issues that affected the data obtained or the instrumentation itself are discussed. The relevance of the data to other noninstrumented turbomachinery is outlined. Conclusions and recommendations resulting from the test series will be presented.

  1. Space Shuttle Main Engine instrumented High Pressure Oxidizer Turbopump technology test bed testing results summary

    NASA Astrophysics Data System (ADS)

    Koelbl, Mary E.

    1993-06-01

    This paper presents the test results from the Space Shuttle Main Engine (SSME) instrumented High Pressure Oxidizer Turbopump (HPOTP). The turbopump was tested on Engine 3001, a highly instrumented engine, in an effort to characterize the turbopump and the engine system. Seven tests, for a total duration of 766 seconds, were performed over a five month time period. The testing was performed at a wide variety of engine conditions. Changes in engine mixture ratio, power level, engine inlet oxidizer pressure, engine inlet fuel pressure, and engine start sequence were made. A discussion of all the HPOTP pressure and temperature data obtained are presented with comparisons to supporting analyses made where applicable. The effect of the various engine conditions on the measured data is addressed. This paper also discusses the challenges that were overcome to obtain the data. The significant instrumentation related problems encountered during the design, fabrication, and testing of this turbopump are summarized. Only those issues that affected the data obtained or the instrumentation itself are discussed. The relevance of the data to other noninstrumented turbomachinery is outlined. Conclusions and recommendations resulting from the test series will be presented.

  2. Overview of NASA White Sands Test Facility Composite Overwrapped Pressure Vessel Testing

    NASA Technical Reports Server (NTRS)

    Greene, Nathanael; Saulsberry, Regor; Thesken, John; Phoenix, Leigh

    2006-01-01

    This viewgraph presentation examines the White Sands Test Facility testing of Composite overwrapped pressure vessel (COPV). A COPV is typically a metallic liner overwrapped with a fiber epoxy matrix. There is a weight advantage over the traditional all metal design. The presentation shows pictures of the facilities at White Sands, and then examines some of the testing performed. The tests include fluids compatibility, and Kevlar COPV. Data for the Kevlar tests are given, and an analysis is reviewed. There is also a comparison between Carbon COPVs and the Kevlar COPVs.

  3. High-pressure oxygen test evaluations. [impact tests/metals - space shuttles

    NASA Technical Reports Server (NTRS)

    Schwinghamer, R. J.; Key, C. F.

    1974-01-01

    The relevance of impact sensitivity testing to the development of the space shuttle main engine is discussed in the light of the special requirements for the engine. The background and history of the evolution of liquid and gaseous oxygen testing techniques and philosophy is discussed also. The parameters critical to reliable testing are treated in considerable detail, and test apparatus and procedures are described and discussed. Materials threshold sensitivity determination procedures are considered and a decision logic diagram for sensitivity threshold determination was plotted. Finally, high-pressure materials sensitivity test data are given for selected metallic and nonmetallic materials.

  4. Self-Pressurization and Spray Cooling Simulations of the Multipurpose Hydrogen Test Bed (MHTB) Ground-Based Experiment

    NASA Technical Reports Server (NTRS)

    Kartuzova, O.; Kassemi, M.; Agui, J.; Moder, J.

    2014-01-01

    This paper presents a CFD (computational fluid dynamics) model for simulating the self-pressurization of a large scale liquid hydrogen storage tank. In this model, the kinetics-based Schrage equation is used to account for the evaporative and condensing interfacial mass flows. Laminar and turbulent approaches to modeling natural convection in the tank and heat and mass transfer at the interface are compared. The flow, temperature, and interfacial mass fluxes predicted by these two approaches during tank self-pressurization are compared against each other. The ullage pressure and vapor temperature evolutions are also compared against experimental data obtained from the MHTB (Multipuprpose Hydrogen Test Bed) self-pressurization experiment. A CFD model for cooling cryogenic storage tanks by spraying cold liquid in the ullage is also presented. The Euler- Lagrange approach is utilized for tracking the spray droplets and for modeling interaction between the droplets and the continuous phase (ullage). The spray model is coupled with the VOF (volume of fluid) model by performing particle tracking in the ullage, removing particles from the ullage when they reach the interface, and then adding their contributions to the liquid. Droplet ullage heat and mass transfer are modeled. The flow, temperature, and interfacial mass flux predicted by the model are presented. The ullage pressure is compared with experimental data obtained from the MHTB spray bar mixing experiment. The results of the models with only droplet/ullage heat transfer and with heat and mass transfer between the droplets and ullage are compared.

  5. Quiz: Does Your Blood Pressure Pass the Test? | NIH MedlinePlus the Magazine

    MedlinePlus

    ... please turn Javascript on. Special Section: Healthy Blood Pressure Quiz: Does Your Blood Pressure Pass the Test? Past Issues / Winter 2010 Table of Contents Blood pressure changes throughout the day. It is highest while ...

  6. Research on reliability test circuit of pneumatic pressure regulator

    NASA Astrophysics Data System (ADS)

    Ma, Jungong; Wang, Haitao; Oneyama, Naotake; Senoo, Mitsuru; Zhang, Huping

    2006-11-01

    In order to evaluate ISO/CD19973-4, some items had been tested, such as step response, valve opening, feasible opening frequency, air consumption, piping influence, cycle response and so on. The results show that Valve opening varies sensitively to the size of piping, solenoid valve and test chamber. The valve of regulator opens to some extent, closes immediately, and never reaches the full opening. If these circuit specifications are defined concretely and observed strictly, it is not impossible to obtain a certain required opening ratio and air consumption is very large. On the side, the compared tests based on the Japanese JIS test circuit having been carried out, the results show that, regardless of test circuit specifications, the valve of regulator always repeats full closing and full opening. The relief valve of the regulator operates too. At the same operating frequency, air consumption is one digit less than the one in ISO/CD 19973-4 circuit. In the end, improved JIS circuit was put forward as a reliability circuit of pneumatic pressure regulator.

  7. Pressurized helium II-cooled magnet test facility

    SciTech Connect

    Warren, R.P.; Lambertson, G.R.; Gilbert, W.S.; Meuser, R.B.; Caspi, S.; Schafer, R.V.

    1980-06-01

    A facility for testing superconducting magnets in a pressurized bath of helium II has been constructed and operated. The cryostat accepts magnets up to 0.32 m diameter and 1.32 m length with current to 3000 A. In initial tests, the volume of helium II surrounding the superconducting magnet was 90 liters. Minimum temperature reached was 1.7 K at which point the pumping system was throttled to maintain steady temperature. Helium II reservoir temperatures were easily controlled as long as the temperature upstream of the JT valve remained above T lambda; at lower temperatures control became difficult. Positive control of the temperature difference between the liquid and cold sink by means of an internal heat source appears necessary to avoid this problem. The epoxy-sealed vessel closures, with which we have had considerable experience with normal helium vacuum, also worked well in the helium II/vacuum environment.

  8. Au@Pt nanoparticle encapsulated target-responsive hydrogel with volumetric bar-chart chip readout for quantitative point-of-care testing.

    PubMed

    Zhu, Zhi; Guan, Zhichao; Jia, Shasha; Lei, Zhichao; Lin, Shuichao; Zhang, Huimin; Ma, Yanli; Tian, Zhong-Qun; Yang, Chaoyong James

    2014-11-10

    Point-of-care testing (POCT) with the advantages of speed, simplicity, portability, and low cost is critical for the measurement of analytes in a variety of environments where access to laboratory infrastructure is lacking. While qualitative POCTs are widely available, quantitative POCTs present significant challenges. Here we describe a novel method that integrates an Au core/Pt shell nanoparticle (Au@PtNP) encapsulated target-responsive hydrogel with a volumetric bar-chart chip (V-Chip) for quantitative POCT. Upon target introduction, the hydrogel immediately dissolves and releases Au@PtNPs, which can efficiently catalyze the decomposition of H2 O2 to generate a large volume of O2 to move of an ink bar in the V-Chip. The concentration of the target introduced can be visually quantified by reading the traveling distance of the ink bar. This method has the potential to be used for portable and quantitative detection of a wide range of targets without any external instrument. PMID:25113247

  9. Hot Gas Cleanup Test Facility for Gasification and Pressurized Combustion

    SciTech Connect

    Sears, R.E.; Griswold, G.H.; Fankhanel, M.O.; Kastner, C.E.; Pontium, D.H.

    1992-11-01

    Efficiencies in advanced power generation systems such as integrated gasification combined cycle, pressurized fluidized bed combustion and integrated gasification fuel cells can be maximized by feeding hot fuel gas or flue gas to the power block. However, advanced gas turbines have strict particulate requirements to minimize wear on the blades due to the close tolerances used to maximize the efficiency of the turbomachinery. Molten Carbonate Fuel Cells also have strict particulate requirements to prevent blinding of the electrodes. Therefore, one of the main barriers to developing these advanced power generation systems is the removal of particulates in a hot gas stream. Although the development of several high temperature/pressure PCD systems has been ongoing for the past several years, long term operation under realistic conditions for advanced power generation has been limited. The demonstration of reliable operation is critical to the commercialization of PCD technology for advanced power generation. The conceptual design of the Hot Gas Cleanup Test Facility Project was expanded to include additional modules to better address the scope of the Cooperative Agreement with the DOE/METC. The expanded test facility, referred to as the Power Systems Development Facility, will provide a flexible test location in which the development of advanced power system components, the evaluation of advanced turbine and fuel cell configurations, and the integration and control issues of these systems. The facility is intended to provide direct support for upcoming DOE demonstrations of power generation technologies utilizing hot stream cleanup and will provide a resource for rigorous testing and performance assessment of hot stream cleanup devices now being developed with the support of DOE/METC.

  10. Ares I Upper Stage Pressure Tests in Wind Tunnel

    NASA Technical Reports Server (NTRS)

    2007-01-01

    Under the goals of the Vision for Space Exploration, Ares I is a chief component of the cost-effective space transportation infrastructure being developed by NASA's Constellation Program. This transportation system will safely and reliably carry human explorers back to the moon, and then onward to Mars and other destinations in the solar system. The Ares I effort includes multiple project element teams at NASA centers and contract organizations around the nation, and is managed by the Exploration Launch Projects Office at NASA's Marshall Space Flight Center (MFSC). ATK Launch Systems near Brigham City, Utah, is the prime contractor for the first stage booster. ATK's subcontractor, United Space Alliance of Houston, is designing, developing and testing the parachutes at its facilities at NASA's Kennedy Space Center in Florida. NASA's Johnson Space Center in Houston hosts the Constellation Program and Orion Crew Capsule Project Office and provides test instrumentation and support personnel. Together, these teams are developing vehicle hardware, evolving proven technologies, and testing components and systems. Their work builds on powerful, reliable space shuttle propulsion elements and nearly a half-century of NASA space flight experience and technological advances. Ares I is an inline, two-stage rocket configuration topped by the Crew Exploration Vehicle, its service module, and a launch abort system. In this HD video image, the first stage reentry 1/2% model is undergoing pressure measurements inside the wind tunnel testing facility at MSFC. (Highest resolution available)

  11. Ambient Pressure Test Rig Developed for Testing Oil-Free Bearings in Alternate Gases and Variable Pressures

    NASA Technical Reports Server (NTRS)

    Bauman, Steven W.

    1990-01-01

    The Oil-Free Turbomachinery research team at the NASA Glenn Research Center is conducting research to develop turbomachinery systems that utilize high-speed, high temperature foil (air) bearings that do not require an oil lubrication system. Such systems combine the most advanced foil bearings from industry with NASA-developed hightemperature solid-lubricant technology. New applications are being pursued, such as Oil- Free turbochargers, auxiliary power units, and turbine propulsion systems for aircraft. An Oil-Free business jet engine, for example, would be simpler, lighter, more reliable, and less costly to purchase and maintain than current engines. Another application is NASA's Prometheus mission, where gas bearings will be required for the closed-cycle turbine based power-conversion system of a nuclear power generator for deep space. To support these applications, Glenn's Oil-Free Turbomachinery research team developed the Ambient Pressure Test Rig. Using this facility, researchers can load and heat a bearing and evaluate its performance with reduced air pressure to simulate high altitude conditions. For the nuclear application, the test chamber can be purged with gases such as helium to study foil gas bearing operation in working fluids other than air.

  12. 49 CFR 178.605 - Hydrostatic pressure test.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... vapor pressure of the filling material and the partial pressure of the air or other inert gas minus 100... subchapter and a filling temperature of 15 °C (59 °F); (2) Not less than 1.75 times the vapor pressure at 50... pressure of 100 kPa (15 psig); or (3) Not less than 1.5 times the vapor pressure at 55 °C (131 °F) of...

  13. Bar dimensions and bar shapes in estuaries

    NASA Astrophysics Data System (ADS)

    Leuven, Jasper; Kleinhans, Maarten; Weisscher, Steven; van der Vegt, Maarten

    2016-04-01

    Estuaries cause fascinating patterns of dynamic channels and shoals. Intertidal sandbars are valuable habitats, whilst channels provide access to harbors. We still lack a full explanation and classification scheme for the shapes and dimensions of bar patterns in natural estuaries, in contrast with bars in rivers. Analytical physics-based models suggest that bar length in estuaries increases with flow velocity, tidal excursion length or estuary width, depending on which model. However, these hypotheses were never validated for lack of data and experiments. We present a large dataset and determine the controls on bar shape and dimensions in estuaries, spanning bar lengths from centimeters (experiments) to 10s of kilometers length. First, we visually identified and classified 190 bars, measured their dimensions (width, length, height) and local braiding index. Data on estuarine geometry and tidal characteristics were obtained from governmental databases and literature on case studies. We found that many complex bars can be seen as simple elongated bars partly cut by mutually evasive ebb- and flood-dominated channels. Data analysis shows that bar dimensions scale with estuary dimensions, in particular estuary width. Breaking up the complex bars in simple bars greatly reduced scatter. Analytical bar theory overpredicts bar dimensions by an order of magnitude in case of small estuarine systems. Likewise, braiding index depends on local width-to-depth ratio, as was previously found for river systems. Our results suggest that estuary dimensions determine the order of magnitude of bar dimensions, while tidal characteristics modify this. We will continue to model bars numerically and experimentally. Our dataset on tidal bars enables future studies on the sedimentary architecture of geologically complex tidal deposits and enables studying effects of man-induced perturbations such as dredging and dumping on bar and channel patterns and habitats.

  14. Development of a new testing equipment that combines the working principles of both the split Hopkinson bar and the drop weight testers.

    PubMed

    Adas, Rateb; Haiba, Majed

    2016-01-01

    In the current work, a new high strain rate tensile testing equipment is proposed. The equipment uses a pendulum device to generate an impact load and a three-bar mechanism to bring that load to act upon a specially designed specimen. As the standard impact testing apparatus uses pendulum device and the well-known SHB high strain rate tester adopts the above-mentioned mechanism, the introduced equipment can be dealt with as an impact apparatus in which the base that supports the V-shape specimen is replaced with the three-bar configuration that the traditional SHB uses. In order to demonstrate the applicability of the new tester, virtual design tools were used to determine the most appropriate configuration for it. Then, a detailed design was created, and a full-scale prototype was produced, calibrated, instrumented and tested. The obtained results demonstrate that the new tester is capable of axially straining steel specimens up to failure at a maximum rate of about 250 s(-1), which is reasonable when compared with a more established high strain rate testers. PMID:27504253

  15. X-33 Metal Model Testing In Low Turbulence Pressure Tunnel

    NASA Technical Reports Server (NTRS)

    1997-01-01

    The countrys next generation of space transportation, a reusable launch vehicle (RLV), continues to undergo wind tunnel testing at NASA Langley Research Center, Hampton, Va. All four photos are a metal model of the X-33 reusable launch vehicle (about 15 inches long by 15 inches wide) being tested for Lockheed Martin Skunk Works in the Low Turbulence Pressure Tunnel (LTPT) at NASA Langley Research Center. Tests are being conducted by members of the Aerothermodynamics Branch. According to Kelly Murphy of Langleys Aerothermodynamics Branch, the aluminum and stainless steel model of the X-33 underwent aerodynamic testing in the tunnel. *The subsonic tests were conducted at the speed of Mach .25,* she said. *Force and moment testing and measurement in this tunnel lasted about one week.* Future testing of the metal model is scheduled for Langleys 16-Foot Transonic Tunnel, from the end of March to mid-April 1997, and the Unitary Wind Tunnel, from mid-April to the beginning of May. Other tunnel testing for X-33 models are scheduled from the present through June in the hypersonic tunnels, and the 14- by 22-Foot Tunnel from about mid-June to mid-July. Since 1991 Marshall Space Flight Center in Huntsville, Ala. has been the lead center for coordinating the Agencys X-33 Reusable Launch Vehicle (RLV) Program, an industry-led effort, which NASA Administrator Daniel S. Goldin has declared the agency's highest priority new program. The RLV Technology Program is a partnership among NASA, the United States Air Force and private industry to develop world leadership in low-cost space transportation. The goal of the program is to develop technologies and new operational concepts that can radically reduce the cost of access to space. The RLV program also hopes to speed the commercialization of space and improve U.S. economic competitiveness by making access to space as routine and reliable as today's airline industry, while reducing costs and enhancing safety and reliability. The RLV

  16. X-33 Metal Model Testing In Low Turbulence Pressure Tunnel

    NASA Technical Reports Server (NTRS)

    1997-01-01

    The countrys next generation of space transportation, a reusable launch vehicle (RLV), continues to undergo wind tunnel testing at NASA Langley Research Center, Hampton, Va. All four photos are a metal model of the X-33 reusable launch vehicle (about 15 inches long by 15 inches wide) being tested for Lockheed Martin Skunk Works in the Low Turbulence Pressure Tunnel (LTPT) at NASA Langley Research Center. Tests are being conducted by members of the Aerothermodynamics Branch. According to Kelly Murphy of Langleys Aerothermodynamics Branch, the aluminum and stainless steel model of the X-33 underwent aerodynamic testing in the tunnel. *The subsonic tests were conducted at the speed of Mach 25,* she said. *Force and moment testing and measurement in this tunnel lasted about one week.* Future testing of the metal model is scheduled for Langleys 16-Foot Transonic Tunnel, from the end of March to mid-April 1997, and the Unitary Wind Tunnel, from mid-April to the beginning of May. Other tunnel testing for X-33 models are scheduled from the present through June in the hypersonic tunnels, and the 14- by 22-Foot Tunnel from about mid-June to mid-July. Since 1991 Marshall Space Flight Center in Huntsville, Ala. has been the lead center for coordinating the Agencys X-33 Reusable Launch Vehicle (RLV) Program, an industry-led effort, which NASA Administrator Daniel S. Goldin has declared the agency's highest priority new program. The RLV Technology Program is a partnership among NASA, the United States Air Force and private industry to develop world leadership in low-cost space transportation. The goal of the program is to develop technologies and new operational concepts that can radically reduce the cost of access to space. The RLV program also hopes to speed the commercialization of space and improve U.S. economic competitiveness by making access to space as routine and reliable as today's airline industry, while reducing costs and enhancing safety and reliability. The RLV

  17. 49 CFR 179.220-24 - Tests of pressure relief valves.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Tests of pressure relief valves. 179.220-24... FOR TANK CARS Specifications for Non-Pressure Tank Car Tanks (Classes DOT-111AW and 115AW) § 179.220-24 Tests of pressure relief valves. Each safety relief valve must be tested by air or gas...

  18. 49 CFR 179.200-23 - Tests of pressure relief valves.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Tests of pressure relief valves. 179.200-23... FOR TANK CARS Specifications for Non-Pressure Tank Car Tanks (Classes DOT-111AW and 115AW) § 179.200-23 Tests of pressure relief valves. (a) Each valve shall be tested by air or gas for compliance...

  19. 49 CFR 179.200-23 - Tests of pressure relief valves.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 3 2013-10-01 2013-10-01 false Tests of pressure relief valves. 179.200-23... CARS Specifications for Non-Pressure Tank Car Tanks (Classes DOT-111AW and 115AW) § 179.200-23 Tests of pressure relief valves. (a) Each valve shall be tested by air or gas for compliance with § 179.15...

  20. 49 CFR 179.300-17 - Tests of pressure relief devices.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Tests of pressure relief devices. 179.300-17... Tests of pressure relief devices. (a) Each valve shall be tested by air or gas before being put into service. The valve shall open and be vapor-tight at the pressure prescribed in § 179.301. (b)...

  1. 49 CFR 179.220-24 - Tests of pressure relief valves.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 3 2013-10-01 2013-10-01 false Tests of pressure relief valves. 179.220-24... CARS Specifications for Non-Pressure Tank Car Tanks (Classes DOT-111AW and 115AW) § 179.220-24 Tests of pressure relief valves. Each safety relief valve must be tested by air or gas for compliance with §...

  2. 46 CFR 56.97-5 - Pressure testing of nonstandard piping system components.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 2 2010-10-01 2010-10-01 false Pressure testing of nonstandard piping system components... ENGINEERING PIPING SYSTEMS AND APPURTENANCES Pressure Tests § 56.97-5 Pressure testing of nonstandard piping system components. (a) All nonstandard piping system components such as welded valves and...

  3. 46 CFR 56.97-5 - Pressure testing of nonstandard piping system components.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 2 2013-10-01 2013-10-01 false Pressure testing of nonstandard piping system components... ENGINEERING PIPING SYSTEMS AND APPURTENANCES Pressure Tests § 56.97-5 Pressure testing of nonstandard piping system components. (a) All nonstandard piping system components such as welded valves and...

  4. 46 CFR 56.97-5 - Pressure testing of nonstandard piping system components.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 2 2014-10-01 2014-10-01 false Pressure testing of nonstandard piping system components... ENGINEERING PIPING SYSTEMS AND APPURTENANCES Pressure Tests § 56.97-5 Pressure testing of nonstandard piping system components. (a) All nonstandard piping system components such as welded valves and...

  5. 46 CFR 56.97-5 - Pressure testing of nonstandard piping system components.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 2 2011-10-01 2011-10-01 false Pressure testing of nonstandard piping system components... ENGINEERING PIPING SYSTEMS AND APPURTENANCES Pressure Tests § 56.97-5 Pressure testing of nonstandard piping system components. (a) All nonstandard piping system components such as welded valves and...

  6. 46 CFR 56.97-5 - Pressure testing of nonstandard piping system components.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 2 2012-10-01 2012-10-01 false Pressure testing of nonstandard piping system components... ENGINEERING PIPING SYSTEMS AND APPURTENANCES Pressure Tests § 56.97-5 Pressure testing of nonstandard piping system components. (a) All nonstandard piping system components such as welded valves and...

  7. 30 CFR 35.21 - Temperature-pressure spray-ignition tests.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Temperature-pressure spray-ignition tests. 35... Temperature-pressure spray-ignition tests. (a) Purpose. The purpose of this test shall be to determine the... the pressure vessel and heated to a temperature of 150 °F. The temperature shall be maintained at...

  8. 30 CFR 35.21 - Temperature-pressure spray-ignition tests.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Temperature-pressure spray-ignition tests. 35... Temperature-pressure spray-ignition tests. (a) Purpose. The purpose of this test shall be to determine the... the pressure vessel and heated to a temperature of 150 °F. The temperature shall be maintained at...

  9. 30 CFR 35.21 - Temperature-pressure spray-ignition tests.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Temperature-pressure spray-ignition tests. 35... Temperature-pressure spray-ignition tests. (a) Purpose. The purpose of this test shall be to determine the... the pressure vessel and heated to a temperature of 150 °F. The temperature shall be maintained at...

  10. 30 CFR 35.21 - Temperature-pressure spray-ignition tests.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Temperature-pressure spray-ignition tests. 35... Temperature-pressure spray-ignition tests. (a) Purpose. The purpose of this test shall be to determine the... the pressure vessel and heated to a temperature of 150 °F. The temperature shall be maintained at...

  11. 30 CFR 250.423 - What are the requirements for pressure testing casing?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... pressure testing casing? (a) The table in this section describes the minimum test pressures for each string... down mechanisms are engaged upon installation of each casing string. (2) If you run a liner that has a... perform additional negative pressure tests on other casing strings or liners (e.g., intermediate...

  12. 30 CFR 250.423 - What are the requirements for pressure testing casing?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... pressure testing casing? (a) The table in this section describes the minimum test pressures for each string... down mechanisms are engaged upon installation of each casing string. (2) If you run a liner that has a... perform additional negative pressure tests on other casing strings or liners (e.g., intermediate...

  13. Development of methods and equipment for bellows assemblies testing under hydrostatic pressure

    NASA Astrophysics Data System (ADS)

    Ol’khovik, E.

    2016-04-01

    The paper presents a newbellows assemblies test method for stop and safety valves. To create the real conditions it is suggested testing under external hydrostatic pressure, which is available in the piping system.A designed test apparatus allows testing of the bellows under the effect of external hydrostatic pressure. The paper describes the design of the apparatus, its specifications and the test procedures.

  14. 49 CFR 178.605 - Hydrostatic pressure test.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... vapor pressure of the filling material and the partial pressure of the air or other inert gas minus 100... subchapter and a filling temperature of 15 °C (59 °F); (2) Not less than 1.75 times the vapor pressure at 50... of 100 kPa (15 psig); or (3) Not less than 1.5 times the vapor pressure at 55 °C (131 °F) of...

  15. 49 CFR 178.605 - Hydrostatic pressure test.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... vapor pressure of the filling material and the partial pressure of the air or other inert gas minus 100... subchapter and a filling temperature of 15 °C (59 °F); (2) Not less than 1.75 times the vapor pressure at 50... of 100 kPa (15 psig); or (3) Not less than 1.5 times the vapor pressure at 55 °C (131 °F) of...

  16. 49 CFR 178.605 - Hydrostatic pressure test.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... vapor pressure of the filling material and the partial pressure of the air or other inert gas minus 100... subchapter and a filling temperature of 15 °C (59 °F); (2) Not less than 1.75 times the vapor pressure at 50... of 100 kPa (15 psig); or (3) Not less than 1.5 times the vapor pressure at 55 °C (131 °F) of...

  17. Cryogenic Autogenous Pressurization Testing for Robotic Refueling Mission 3

    NASA Technical Reports Server (NTRS)

    Boyle, R.; DiPirro, M.; Tuttle, J.; Francis, J.; Mustafi, S.; Li, X.; Barfknecht, P.; DeLee, C. H.; McGuire, J.

    2015-01-01

    A wick-heater system has been selected for use to pressurize the Source Dewar of the Robotic Refueling Mission Phase 3 on-orbit cryogen transfer experiment payload for the International Space Station. Experimental results of autogenous pressurization of liquid argon and liquid nitrogen using a prototype wick-heater system are presented. The wick-heater generates gas to increase the pressure in the tank while maintaining a low bulk fluid temperature. Pressurization experiments were performed in 2013 to characterize the performance of the wick heater. This paper describes the experimental setup, pressurization results, and analytical model correlations.

  18. Laboratory evaluation of the pressure water level data logger manufactured by Infinities USA, Inc.: results of pressure and temperature tests

    USGS Publications Warehouse

    Carnley, Mark V.

    2015-01-01

    The Pressure Water Level Data Logger manufactured by Infinities USA, Inc., was evaluated by the U.S. Geological Survey (USGS) Hydrologic Instrumentation Facility for conformance with the manufacturer’s stated accuracy specifications for measuring pressure throughout the device’s operating temperature range and with the USGS accuracy requirements for water-level measurements. The Pressure Water Level Data Logger (Infinities Logger) is a submersible, sealed, water-level sensing device with an operating pressure range of 0 to 11.5 feet of water over a temperature range of −18 to 49 degrees Celsius. For the pressure range tested, the manufacturer’s accuracy specification of 0.1 percent of full scale pressure equals an accuracy of ±0.138 inch of water. Three Infinities Loggers were evaluated, and the testing procedures followed and results obtained are described in this report. On the basis of the test results, the device is poorly compensated for temperature. For the three Infinities Loggers, the mean pressure differences varied from –4.04 to 5.32 inches of water and were not within the manufacturer’s accuracy specification for pressure measurements made within the temperature-compensated range. The device did not meet the manufacturer’s stated accuracy specifications for pressure within its temperature-compensated operating range of –18 to 49 degrees Celsius or the USGS accuracy requirements of no more than 0.12 inch of water (0.01 foot of water) or 0.10 percent of reading, whichever is larger. The USGS accuracy requirements are routinely examined and reported when instruments are evaluated at the Hydrologic Instrumentation Facility. The estimated combined measurement uncertainty for the pressure cycling test was ±0.139 inch of water, and for temperature, the cycling test was ±0.127 inch of water for the three Infinities Loggers.

  19. 49 CFR 179.300-17 - Tests of pressure relief devices.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 3 2013-10-01 2013-10-01 false Tests of pressure relief devices. 179.300-17... pressure relief devices. (a) Each valve shall be tested by air or gas before being put into service. The valve shall open and be vapor-tight at the pressure prescribed in § 179.301. (b) Rupture disks of...

  20. 30 CFR 250.425 - What are the requirements for pressure testing liners?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... liners? 250.425 Section 250.425 Mineral Resources BUREAU OF SAFETY AND ENVIRONMENTAL ENFORCEMENT... pressure testing liners? (a) You must test each drilling liner (and liner-lap) to a pressure at least equal to the anticipated pressure to which the liner will be subjected during the formation...

  1. 30 CFR 250.425 - What are the requirements for pressure testing liners?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... liners? 250.425 Section 250.425 Mineral Resources BUREAU OF SAFETY AND ENVIRONMENTAL ENFORCEMENT... pressure testing liners? (a) You must test each drilling liner (and liner-lap) to a pressure at least equal to the anticipated pressure to which the liner will be subjected during the formation...

  2. 30 CFR 250.425 - What are the requirements for pressure testing liners?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... liners? 250.425 Section 250.425 Mineral Resources BUREAU OF SAFETY AND ENVIRONMENTAL ENFORCEMENT... pressure testing liners? (a) You must test each drilling liner (and liner-lap) to a pressure at least equal to the anticipated pressure to which the liner will be subjected during the formation...

  3. 30 CFR 250.425 - What are the requirements for pressure testing liners?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... liners? 250.425 Section 250.425 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT, REGULATION, AND... requirements for pressure testing liners? (a) You must test each drilling liner (and liner-lap) to a pressure at least equal to the anticipated pressure to which the liner will be subjected during the...

  4. Characterization Testing of H20-SO2 Electrolyzer at Ambient Pressure

    SciTech Connect

    Steimke, J

    2005-07-29

    This document reports work performed at the Savannah River National Laboratory (SRNL) that resulted in a major accomplishment by demonstrating the proof-of-concept of the use of a proton exchange membrane or PEM-type electrochemical cell to produce hydrogen via SO{sub 2}-depolarized water electrolysis. For the first time sulfur dioxide dissolved in liquid sulfuric acid was used to depolarize water electrolysis in a modern PEM cell. The use of such a cell represents a major step in achieving the ultimate goal of an economical hydrogen production process based on the Hybrid Sulfur (HyS) Cycle. The HyS Process is a hybrid thermochemical cycle that may be used in conjunction with advanced nuclear reactors or centralized solar receivers to produce hydrogen by water-splitting. Like all other sulfur-based cycles, HyS utilizes the high temperature thermal decomposition of sulfuric acid to produce oxygen. The unique aspect of HyS is the generation of hydrogen in a water electrolyzer that is operated under conditions where dissolved sulfur dioxide depolarizes the anodic reaction, resulting in substantial voltage reduction. Sulfur dioxide is oxidized at the anode, producing sulfuric acid, that is sent to the acid decomposition portion of the cycle. The focus of this work was to conduct single cell electrolyzer tests in order to prove the concept of SO{sub 2}-depolarization and to determine how the results can be used to evaluate the performance of key components of the HyS Process. A test facility for conducting SO{sub 2}-depolarized electrolyzer (SDE) testing was designed, constructed and commissioned. The maximum cell current is 50 amperes, which is equivalent to a hydrogen production rate of approximately 20 liters per hour. The test facility was designed for operation at room temperature with pressures up to 2 bar. Feed to the anode of the electrolyzer can be water, sulfuric acid of various concentrations, or sulfuric acid containing dissolved sulfur dioxide. Provisions

  5. How to pressurize autoclaves for corrosion testing under CO{sub 2} and H{sub 2}S pressure

    SciTech Connect

    Crolet, J.L.; Bonis, M.R.

    1998-12-31

    All the methods presently used for pressurizing autoclaves have their advantages and disadvantages. Pressurizing with pure gases is undoubtedly the surest method, since it is insensitive to the autoclave filling rate, and the influence of temperature stability can be readily controlled. The only limitation is the impossibility of accurately reproducing very low H{sub 2}S partial pressures (< 30 mbar) at high temperatures (> 150 C). Conventional pressurizing with gas mixtures is not at all practical, since it demands either excessively large autoclaves or the bubbling of prohibitive volumes of gas. In order to overcome these fundamental difficulties, alternative methods are proposed, such as high temperature bubbling using a cooled reflux condenser, or presaturation of the autoclave at 60 C at a fraction of the test pressure, enabling the latter to be attained during subsequent heating by the natural increase in pressure with temperature. This study is relevant for the oil and gas industries.

  6. New Constraints on the Galactic Bar

    NASA Astrophysics Data System (ADS)

    Minchev, I.; Nordhaus, J.; Quillen, A. C.

    2007-07-01

    Previous work has related the Galactic bar to structure in the local stellar velocity distribution. Here we show that the bar also influences the spatial gradients of the velocity vector via the Oort constants. By numerical integration of test particles we simulate measurements of the Oort C-value in a gravitational potential including the Galactic bar. We account for the observed trend that C is increasingly negative for stars with higher velocity dispersion. By comparing measurements of C with our simulations we improve on previous models of the bar, estimating that the bar pattern speed is Ωb/Ω0=1.87+/-0.04, where Ω0 is the local circular frequency, and the bar angle lies within 20deg<=φ0<=45deg. We find that the Galactic bar affects measurements of the Oort constants A and B less than ~2 km s-1 kpc-1 for the hot stars.

  7. New Constraints on the Galactic Bar

    NASA Astrophysics Data System (ADS)

    Minchev, Ivan; Nordhaus, J.; Quillen, A. C.

    2007-07-01

    Previous work has related the Galactic Bar to structure in the local stellar velocity distribution. Here we show that the Bar also influences the spatial gradients of the velocity vector via the Oort constants. By numerical integration of test-particles we simulate measurements of the Oort C-value in a gravitational potential including the Galactic Bar. We account for the observed trend that C is increasingly negative for stars with higher velocity dispersion. By comparing measurements of C with our simulations we improve on previous models of the Bar, estimating that the Bar pattern speed is Omega_b/Omega_0=1.87\\pm0.04, where Omega_0 is the local circular frequency, and the Bar angle lies within 20Bar affects measurements of the Oort constants A and B less than 2 km/s/kpc for the hot stars.

  8. Test Structures for Rapid Prototyping of Gas and Pressure Sensors

    NASA Technical Reports Server (NTRS)

    Buehler, M.; Cheng, L. J.; Martin, D.

    1996-01-01

    A multi-project ceramic substrate was used in developing a gas sensor and pressure sensor. The ceramic substrate cantained 36 chips with six variants including sensors, process control monitors, and an interconnect ship. Tha gas sensor is being developed as an air quality monitor and the pressure gauge as a barometer.

  9. 30 CFR 250.1609 - Pressure testing of casing.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    .... (When oil or gas is not present in the cap rock, the production liner need not be cemented in place... conductor casing string or 12 hours under pressure for all other casing strings. Cement is considered under pressure if one or more float valves are shown to be holding the cement in place or when other means...

  10. Development and Validation of a Pressurization System Model for a Crossfeed Subscale Water Test Article

    NASA Technical Reports Server (NTRS)

    Nguyen, Han; Mazurkivich, Pete

    2006-01-01

    A pressurization system model was developed for a crossfeed subscale water test article using the EASY5 modeling software. The model consisted of an integrated tank pressurization and pressurization line model. The tank model was developed using the general purpose library, while the line model was assembled from the gas dynamic library. The pressurization system model was correlated to water test data obtained from nine test runs conducted on the crossfeed subscale test article. The model was first correlated to a representative test run and frozen. The correlated model was then used to predict the tank pressures and compared with the test data for eight other runs. The model prediction showed excellent agreement with the test data, allowing it to be used in a later study to analyze the pressurization system performance of a full-scale bimese vehicle with cryogenic propellants.

  11. Device for testing closure disks at high rates of change of pressure

    DOEpatents

    Merten, Jr., Charles W.

    1993-11-09

    A device for testing the burst pressure of closure disks which provides high pressure to both sides of a disk and rapidly releases pressure from one side thereof causing a high rate of change of pressure. A hollow notched plug allows the rapid release of pressure upon rupturing. A means is also disclosed for transmitting a tensile load from a piston to a hollow notched plug and for sealing the means for transmitting load within a hole in a piston.

  12. Barometric pressure transient testing applications at the Nevada Test Site. Nuclear chimney analysis. Final report

    SciTech Connect

    Hanson, J.M.

    1985-12-01

    Investigations of barometric pressure testing of NTS nuclear chimneys were reviewed. This review includes the models used in the interpretation, methods of analysis, and results. Analytic and semi-analytic models were presented and applied to both historical data and new data taken for this current project. An interpretation technique based on non-linear least squares methods was used to analyze this data in terms of historic and more recent chimney models. Finally, a detailed discussion of radioactive gas transport due to surface barometric pressure fluctuations was presented. This mechanism of transport, referred to as ''barometric pumping,'' is presented in terms of conditions likely to be encountered at the NTS. The report concludes with a discussion of the current understanding of gas flow properties in the alluvial and volcanic areas of the NTS, and suggestions for future efforts directed toward increasing this understanding are presented.

  13. 30 CFR 250.427 - What are the requirements for pressure integrity tests?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... integrity tests? 250.427 Section 250.427 Mineral Resources MINERALS MANAGEMENT SERVICE, DEPARTMENT OF THE... Operations Casing and Cementing Requirements § 250.427 What are the requirements for pressure integrity tests? You must conduct a pressure integrity test below the surface casing or liner and all...

  14. 49 CFR 179.400-21 - Test of pressure relief valves.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 3 2013-10-01 2013-10-01 false Test of pressure relief valves. 179.400-21 Section 179.400-21 Transportation Other Regulations Relating to Transportation (Continued) PIPELINE AND... 107A) § 179.400-21 Test of pressure relief valves. Each valve must be tested with air or gas...

  15. 49 CFR 179.400-21 - Test of pressure relief valves.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Test of pressure relief valves. 179.400-21 Section 179.400-21 Transportation Other Regulations Relating to Transportation PIPELINE AND HAZARDOUS...-113 and 107A) § 179.400-21 Test of pressure relief valves. Each valve must be tested with air or...

  16. 49 CFR 179.400-21 - Test of pressure relief valves.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 107A) § 179.400-21 Test of pressure relief valves. Each valve must be tested with air or gas for... 49 Transportation 3 2011-10-01 2011-10-01 false Test of pressure relief valves. 179.400-21 Section 179.400-21 Transportation Other Regulations Relating to Transportation (Continued) PIPELINE...

  17. 49 CFR 179.400-21 - Test of pressure relief valves.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 3 2014-10-01 2014-10-01 false Test of pressure relief valves. 179.400-21 Section 179.400-21 Transportation Other Regulations Relating to Transportation (Continued) PIPELINE AND... 107A) § 179.400-21 Test of pressure relief valves. Each valve must be tested with air or gas...

  18. Development test report for the high pressure water jet system nozzles

    SciTech Connect

    Takasumi, D.S.

    1995-09-28

    The high pressure water jet nozzle tests were conducted to identify optimum water pressure, water flow rate, nozzle orifice size and fixture configuration needed to effectively decontaminate empty fuel storage canisters in KE-Basin. This report gives the tests results and recommendations from the these tests.

  19. Fixture tests bellows reliability through repetitive pressure/temperature cycling

    NASA Technical Reports Server (NTRS)

    Levinson, C.

    1967-01-01

    Fixture explores the reliability of bellows used in precision in inertial systems. The fixture establishes the ability of the bellows to withstand repetitive over-stress pressure cycling at elevated temperatures. It is applicable in quality control and reliability programs.

  20. Detection of leaks in a water-cooled generator stator bar using perfluorocarbon tracers

    SciTech Connect

    Loss, W.M.; Dietz, R.N.; Senum, G.I.

    1989-12-01

    A generator stator bar with a suspected leak was removed from the ConEdison Ravenswood power plant and shipped to an independent laboratory for hydraulic pressure testing. The test failed to demonstrate the location and magnitude of leaks. The stator bar was subsequently investigated at Brookhaven's Tracer Technology Center. Pressurization with 3 ppM PMCP (perfluoromethylcyclopentane) in hydrogen as carrier gas revealed a leak close to the turbine end of the generator. The equivalent water leak rate was calculated to be about 1/2 mL per day at 30 psi water pressure. A series of tests was designed to first verify the existence of potential leaks and then to locate these leaks as accurately as possible. Enclosing the bar in a flexible hose, introducing nitrogen gas into the hose and analyzing the hose exhaust with Brookhaven's Dual Trap Analyzer successfully identified the existence of leaks. However, the technique failed to locate the approximation position of the suspected leaks. It was found that diffusion and the existence of a laminar flow regime inside the hose prevented the formation of uniform concentration levels and, hence, consistent readings. Successful leak pinpointing was accomplished by wrapping short sections of the bar in plastic bags. This approach with some suggested improvements is also recommended for future experiments with stator bars. 6 figs., 1 tab.

  1. Interpretation of Redondo Creek Field pressure buildup tests

    SciTech Connect

    Fallon, J.B.

    1982-01-01

    Recent pressure buildup analyses of Redondo Creek Field wells have been facilitated by identification of wellbore storage. The wellbore storage coefficient observed immediately after shut-in is controlled by the compressibility of the two-phase wellbore fluid, but the coefficient decreases when the wellbore storage is controlled by a rising liquid level. Identification of such phenomena aids in defining the correct radial flow regime of the pressure buildup response.

  2. Cryogenic & Gas System Piping Pressure Tests (A Collection of PT Permits)

    SciTech Connect

    Rucinski, Russell A.; /Fermilab

    2002-08-22

    This engineering note is a collection of pipe pressure testing documents for various sections of piping for the D-Zero cryogenic and gas systems. High pressure piping must conform with FESHM chapter 5031.1. Piping lines with ratings greater than 150 psig have a pressure test done before the line is put into service. These tests require the use of pressure testing permits. It is my intent that all pressure piping over which my group has responsibility conforms to the chapter. This includes the liquid argon and liquid helium and liquid nitrogen cryogenic systems. It also includes the high pressure air system, and the high pressure gas piping of the WAMUS and MDT gas systems. This is not an all inclusive compilation of test documentation. Some piping tests have their own engineering note. Other piping section test permits are included in separate safety review documents. So if it isn't here, that doesn't mean that it wasn't tested. D-Zero has a back up air supply system to add reliability to air compressor systems. The system includes high pressure piping which requires a review per FESHM 5031.1. The core system consists of a pressurized tube trailer, supply piping into the building and a pressure reducing regulator tied into the air compressor system discharge piping. Air flows from the trailer if the air compressor discharge pressure drops below the regulator setting. The tube trailer is periodically pumped back up to approximately 2000 psig. A high pressure compressor housed in one of the exterior buildings is used for that purpose. The system was previously documented, tested and reviewed for Run I, except for the recent addition of piping to and from the high pressure compressor. The following documents are provided for review of the system: (1) Instrument air flow schematic, drg. 3740.000-ME-273995 rev. H; (2) Component list for air system; (3) Pressure testing permit for high pressure piping; (4) Documentation from Run I contained in D-Zero Engineering note

  3. Payload and Components Real-Time Automated Test System (PACRATS), Data Acquisition of Leak Rate and Pressure Data Test Procedure

    NASA Technical Reports Server (NTRS)

    Rinehart, Maegan L.

    2011-01-01

    The purpose of this activity is to provide the Mechanical Components Test Facility (MCTF) with the capability to obtain electronic leak test and proof pressure data, Payload and Components Real-time Automated Test System (PACRATS) data acquisition software will be utilized to display real-time data. It will record leak rates and pressure/vacuum level(s) simultaneously. This added functionality will provide electronic leak test and pressure data at specified sampling frequencies. Electronically stored data will provide ES61 with increased data security, analysis, and accuracy. The tasks performed in this procedure are to verify PACRATS only, and are not intended to provide verifications for MCTF equipment.

  4. Evaluation of Acoustic Emission SHM of PRSEUS Composite Pressure Cube Tests

    NASA Technical Reports Server (NTRS)

    Horne, Michael R.; Madaras, Eric I.

    2013-01-01

    A series of tests of the Pultruded Rod Stitched Efficient Unitized Structure (PRSEUS) pressure cube were conducted during third quarter 2011 at NASA Langley Research Center (LaRC) in the Combined Loads Test facility (COLTS). This is a report of the analysis of the Acoustic Emission (AE) data collected during those tests. The AE signals of the later tests are consistent with the final failure progression through two of the pressure cube panels. Calibration tests and damage precursor AE indications, from preliminary checkout pressurizations, indicated areas of concern that eventually failed. Hence those tests have potential for vehicle health monitoring.

  5. Pressure vessels and piping systems: general requirements and documentation for testing

    SciTech Connect

    Blyukher, B; Borzileri, C; Brailovsky, Y; Tsicalo, A

    1999-02-25

    Pressure vessel and piping systems are widely used throughout industry and research laboratories and contain a very large concentration of energy, and yet, despite the fact that their design and installation comply with federal, state and local regulations and recognized industrial standards, there continue to be serious pressure equipment failures. There are many reasons for pressure equipment failure: degradation and thinning of materials with usage, aging, hidden flaws during fabrication, etc. Fortunately, periodic testing and internal and external inspections significantly improve the safety of a pressure vessel or facility. A good testing and inspection program is based on development of procedures for specific industries or types of vessels. This paper describes the elements that should be a part of a pressure testing safety program and the requirements that it should address. The program should comply with pressure safety standards and include the requirements for inspecting pressure vessels, establishing and implementing a written pressure system test work permit, maintaining safety in the testing area, developing in-place pressure testing procedures, keeping records for pressure test calculations and results, and evaluating the system's internal and external integrity.

  6. 49 CFR 178.346-5 - Pressure and leakage tests.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... is equipped with vapor recovery equipment may be leakage tested in accordance with 40 CFR 63.425(e). To satisfy the leakage test requirements of this paragraph, the test specified in 40 CFR 63.425(e)(1) must be conducted using air. The hydrostatic test alternative permitted under Appendix A to 40 CFR...

  7. 49 CFR 178.346-5 - Pressure and leakage tests.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... is equipped with vapor recovery equipment may be leakage tested in accordance with 40 CFR 63.425(e). To satisfy the leakage test requirements of this paragraph, the test specified in 40 CFR 63.425(e)(1) must be conducted using air. The hydrostatic test alternative permitted under Appendix A to 40 CFR...

  8. 49 CFR 178.346-5 - Pressure and leakage tests.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... is equipped with vapor recovery equipment may be leakage tested in accordance with 40 CFR 63.425(e). To satisfy the leakage test requirements of this paragraph, the test specified in 40 CFR 63.425(e)(1) must be conducted using air. The hydrostatic test alternative permitted under Appendix A to 40 CFR...

  9. 49 CFR 178.346-5 - Pressure and leakage tests.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... is equipped with vapor recovery equipment may be leakage tested in accordance with 40 CFR 63.425(e). To satisfy the leakage test requirements of this paragraph, the test specified in 40 CFR 63.425(e)(1) must be conducted using air. The hydrostatic test alternative permitted under Appendix A to 40 CFR...

  10. Force and pressure tests of the GA(W)-1 airfoil with a 20% aileron and pressure tests with a 30% Fowler flap

    NASA Technical Reports Server (NTRS)

    Wentz, W. H., Jr.; Seetharam, H. C.; Fiscko, K. A.

    1977-01-01

    Wind tunnel force and pressure tests were conducted for the GA(W)-1 airfoil equipped with a 20% aileron, and pressure tests were conducted with a 30% Fowler flap. All tests were conducted at a Reynolds number of 2.2 and a Mach number of 0.13. The aileron provides control effectiveness similar to ailerons applied to more conventional airfoils. Effects of aileron gaps from 0% to 2% chord were evaluated, as well as hinge moment characteristics. The aft camber of the GA(W)-1 section results in a substantial up-aileron moment, but the hinge moments associated with aileron deflection are similar to other configurations. Fowler flap pressure distributions indicate that unseparated flow is achieved for flap settings up to 40 deg., over a limited angle of attack range. Theoretical pressure distributions compare favorably with experiments for low flap deflections, but show substantial errors at large deflections.

  11. Five-Minute Awake Snoring Test for Determining CPAP Pressures (Five-Minute CPAP Test): A Pilot Study

    PubMed Central

    Camacho, Macario; Ruoff, Chad M.; Kawai, Makoto; Modi, Rahul; Arbee, Jabri; Hekmat, Anahid; Robertson, Matthew; Certal, Victor; Capasso, Robson; Kushida, Clete A.

    2016-01-01

    Objective. To develop a quick, simple, bedside test for determining continuous positive airway pressures (CPAP) for obstructive sleep apnea (OSA) patients. Study Design. Prospective case series at a tertiary medical center. Methods. The Five-Minute Awake Snoring Test for Determining CPAP (Five-Minute CPAP Test) was developed and tested. Patients wear a soft-gel nasal triangle mask while holding a tongue depressor with the wide section (1.75 cm) between the teeth. Fixed pressure nasal CPAP is applied while the patient simulates snoring at 4 centimeters of water pressure. The pressure is incrementally titrated up and then down to determine the lowest pressure at which the patient cannot snore (Quiet Pressure). Results. Overall, thirty-eight patients participated. All could simulate snoring. Correlation coefficients were statistically significant between Quiet Pressures and body mass index (rs = 0.60 [strong positive relationship], p = 0.0088), apnea-hypopnea index (rs = 0.49 [moderate positive relationship], p = 0.039), lowest oxygen saturation (rs = −0.47 [moderate negative relationship], p = 0.048), and oxygen desaturation index (rs = 0.62 [strong positive relationship], p = 0.0057). Conclusion. This pilot study introduces a new concept, which is the final product of over one year of exploration, development, and testing. Five-Minute CPAP Test is a quick, inexpensive, and safe bedside test based on supine awake simulated snoring with nasal CPAP. PMID:26881088

  12. Five-Minute Awake Snoring Test for Determining CPAP Pressures (Five-Minute CPAP Test): A Pilot Study.

    PubMed

    Camacho, Macario; Ruoff, Chad M; Kawai, Makoto; Modi, Rahul; Arbee, Jabri; Hekmat, Anahid; Robertson, Matthew; Zaghi, Soroush; Certal, Victor; Capasso, Robson; Kushida, Clete A

    2016-01-01

    Objective. To develop a quick, simple, bedside test for determining continuous positive airway pressures (CPAP) for obstructive sleep apnea (OSA) patients. Study Design. Prospective case series at a tertiary medical center. Methods. The Five-Minute Awake Snoring Test for Determining CPAP (Five-Minute CPAP Test) was developed and tested. Patients wear a soft-gel nasal triangle mask while holding a tongue depressor with the wide section (1.75 cm) between the teeth. Fixed pressure nasal CPAP is applied while the patient simulates snoring at 4 centimeters of water pressure. The pressure is incrementally titrated up and then down to determine the lowest pressure at which the patient cannot snore (Quiet Pressure). Results. Overall, thirty-eight patients participated. All could simulate snoring. Correlation coefficients were statistically significant between Quiet Pressures and body mass index (r s = 0.60 [strong positive relationship], p = 0.0088), apnea-hypopnea index (r s = 0.49 [moderate positive relationship], p = 0.039), lowest oxygen saturation (r s = -0.47 [moderate negative relationship], p = 0.048), and oxygen desaturation index (r s = 0.62 [strong positive relationship], p = 0.0057). Conclusion. This pilot study introduces a new concept, which is the final product of over one year of exploration, development, and testing. Five-Minute CPAP Test is a quick, inexpensive, and safe bedside test based on supine awake simulated snoring with nasal CPAP. PMID:26881088

  13. Reducing uncertainty in geostatistical description with well testing pressure data

    SciTech Connect

    Reynolds, A.C.; He, Nanqun; Oliver, D.S.

    1997-08-01

    Geostatistics has proven to be an effective tool for generating realizations of reservoir properties conditioned to static data, e.g., core and log data and geologic knowledge. Due to the lack of closely spaced data in the lateral directions, there will be significant variability in reservoir descriptions generated by geostatistical simulation, i.e., significant uncertainty in the reservoir descriptions. In past work, we have presented procedures based on inverse problem theory for generating reservoir descriptions (rock property fields) conditioned to pressure data and geostatistical information represented as prior means for log-permeability and porosity and variograms. Although we have shown that the incorporation of pressure data reduces the uncertainty below the level contained in the geostatistical model based only on static information (the prior model), our previous results assumed did not explicitly account for uncertainties in the prior means and the parameters defining the variogram model. In this work, we investigate how pressure data can help detect errors in the prior means. If errors in the prior means are large and are not taken into account, realizations conditioned to pressure data represent incorrect samples of the a posteriori probability density function for the rock property fields, whereas, if the uncertainty in the prior mean is incorporated properly into the model, one obtains realistic realizations of the rock property fields.

  14. An evaluation of pressure and flow measurement in the Molten Salt Test Loop (MSTL) system.

    SciTech Connect

    Gill, David Dennis; Kolb, William J.; Briggs, Ronald J.

    2013-07-01

    The National Solar Thermal Test Facility at Sandia National Laboratories has a unique test capability called the Molten Salt Test Loop (MSTL) system. MSTL allows customers and researchers to test components in flowing, molten nitrate salt at plant-like conditions for pressure, flow, and temperature. An important need in thermal storage systems that utilize molten salts is for accurate flow and pressure measurement at temperatures above 535%C2%B0C. Currently available flow and pressure instrumentation for molten salt is limited to 535%C2%B0C and even at this temperature the pressure measurement appears to have significant variability. It is the design practice in current Concentrating Solar Power plants to measure flow and pressure on the cold side of the process or in dead-legs where the salt can cool, but this practice won't be possible for high temperature salt systems. For this effort, a set of tests was conducted to evaluate the use of the pressure sensors for flow measurement across a device of known flow coefficient Cv. To perform this task, the pressure sensors performance was evaluated and was found to be lacking. The pressure indicators are severely affected by ambient conditions and were indicating pressure changes of nearly 200psi when there was no flow or pressure in the system. Several iterations of performance improvement were undertaken and the pressure changes were reduced to less than 15psi. The results of these pressure improvements were then tested for use as flow measurement. It was found that even with improved pressure sensors, this is not a reliable method of flow measurement. The need for improved flow and pressure measurement at high temperatures remains and will need to be solved before it will be possible to move to high temperature thermal storage systems with molten salts.

  15. 49 CFR 178.346-5 - Pressure and leakage tests.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... CFR 63.425(e). To satisfy the leakage test requirements of this paragraph, the test specified in 40 CFR 63.425(e)(1) must be conducted using air. The hydrostatic test alternative permitted under Appendix A to 40 CFR Part 60 (“Method 27—Determination of Vapor Tightness of Gasoline Delivery Tank...

  16. Locating of leaks in water-cooled generator stator bars using perfluorocarbon tracers

    SciTech Connect

    Loss, W.M.; Dietz, R.N.

    1991-09-01

    Water cooled stator bars in power plant generators often fail during the maintenance cycle due to water leakage. After the hydrogen pressure in the generator shell has been released water can leak through cracks in the copper and through the insulation. Leaking bars, but not the leaks themselves, are detected with so-called ``hi-pot`` (high potential) tests where direct electrical current is applied to the stator bar windings. A study initiated by ConEd and Brookhaven`s Tracer Technology Center to explore the cause of these leakage problems to determine if the failures originate in the manufacturing process or are created in service by phase related torque stresses. To this purpose bars that had failed the hi-pot test were investigated first with the insulation in place and then stripped to the bare copper. The bars were pressurized with gases containing perfluorocarbon tracers and the magnitude and location of the leaks was detected by using tracers technology principles and instruments such as the ``double source`` method and the Dual Trap Analyzer. In the second part of the project the windings within a generator were tested in-situ for leaks during an outage using tracer principles. Recommendations are given suggesting the shut down of stator bar cooling water before hydrogen bleeding during outages and a revision of the current vent flow rate. The new standard should establish a reasonable leak rate for the stator bar windings proper and exclude leakage of pump seals and connections. Testing during the maintenance cycle in generators should include routine tracer leak detection following the hi-pot test.

  17. Locating of leaks in water-cooled generator stator bars using perfluorocarbon tracers

    SciTech Connect

    Loss, W.M.; Dietz, R.N.

    1991-09-01

    Water cooled stator bars in power plant generators often fail during the maintenance cycle due to water leakage. After the hydrogen pressure in the generator shell has been released water can leak through cracks in the copper and through the insulation. Leaking bars, but not the leaks themselves, are detected with so-called hi-pot'' (high potential) tests where direct electrical current is applied to the stator bar windings. A study initiated by ConEd and Brookhaven's Tracer Technology Center to explore the cause of these leakage problems to determine if the failures originate in the manufacturing process or are created in service by phase related torque stresses. To this purpose bars that had failed the hi-pot test were investigated first with the insulation in place and then stripped to the bare copper. The bars were pressurized with gases containing perfluorocarbon tracers and the magnitude and location of the leaks was detected by using tracers technology principles and instruments such as the double source'' method and the Dual Trap Analyzer. In the second part of the project the windings within a generator were tested in-situ for leaks during an outage using tracer principles. Recommendations are given suggesting the shut down of stator bar cooling water before hydrogen bleeding during outages and a revision of the current vent flow rate. The new standard should establish a reasonable leak rate for the stator bar windings proper and exclude leakage of pump seals and connections. Testing during the maintenance cycle in generators should include routine tracer leak detection following the hi-pot test.

  18. Ultrasonic Nondestructive Evaluation of PRSEUS Pressure Cube Article in Support of Load Test to Failure

    NASA Technical Reports Server (NTRS)

    Johnston, Patrick H.

    2013-01-01

    The PRSEUS Pressure Cube Test was a joint development effort between the Boeing Company and NASA Langley Research Center, sponsored in part by the Environmentally Responsible Aviation Project and Boeing internal R&D. This Technical Memorandum presents the results of ultrasonic inspections in support of the PRSEUS Pressure Cube Test, and is a companion document with the NASA test report and a report on the acoustic emission measurements made during the test.

  19. 30 CFR 250.426 - What are the recordkeeping requirements for casing and liner pressure tests?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 2 2014-07-01 2014-07-01 false What are the recordkeeping requirements for casing and liner pressure tests? 250.426 Section 250.426 Mineral Resources BUREAU OF SAFETY AND... recordkeeping requirements for casing and liner pressure tests? You must record the time, date, and results...

  20. 30 CFR 250.426 - What are the recordkeeping requirements for casing and liner pressure tests?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 2 2011-07-01 2011-07-01 false What are the recordkeeping requirements for casing and liner pressure tests? 250.426 Section 250.426 Mineral Resources BUREAU OF OCEAN ENERGY... § 250.426 What are the recordkeeping requirements for casing and liner pressure tests? You must...

  1. 30 CFR 250.426 - What are the recordkeeping requirements for casing and liner pressure tests?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 2 2013-07-01 2013-07-01 false What are the recordkeeping requirements for casing and liner pressure tests? 250.426 Section 250.426 Mineral Resources BUREAU OF SAFETY AND... recordkeeping requirements for casing and liner pressure tests? You must record the time, date, and results...

  2. 30 CFR 250.426 - What are the recordkeeping requirements for casing and liner pressure tests?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 2 2012-07-01 2012-07-01 false What are the recordkeeping requirements for casing and liner pressure tests? 250.426 Section 250.426 Mineral Resources BUREAU OF SAFETY AND... recordkeeping requirements for casing and liner pressure tests? You must record the time, date, and results...

  3. 49 CFR 179.220-24 - Tests of pressure relief valves.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... pressure relief valves. Each safety relief valve must be tested by air or gas for compliance with § 179.15... 49 Transportation 3 2011-10-01 2011-10-01 false Tests of pressure relief valves. 179.220-24 Section 179.220-24 Transportation Other Regulations Relating to Transportation (Continued) PIPELINE...

  4. 49 CFR 179.200-23 - Tests of pressure relief valves.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... pressure relief valves. (a) Each valve shall be tested by air or gas for compliance with § 179.15 before... 49 Transportation 3 2011-10-01 2011-10-01 false Tests of pressure relief valves. 179.200-23 Section 179.200-23 Transportation Other Regulations Relating to Transportation (Continued) PIPELINE...

  5. 49 CFR 179.200-23 - Tests of pressure relief valves.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 3 2014-10-01 2014-10-01 false Tests of pressure relief valves. 179.200-23 Section 179.200-23 Transportation Other Regulations Relating to Transportation (Continued) PIPELINE AND... pressure relief valves. (a) Each valve shall be tested by air or gas for compliance with § 179.15...

  6. 49 CFR 179.220-24 - Tests of pressure relief valves.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 3 2014-10-01 2014-10-01 false Tests of pressure relief valves. 179.220-24 Section 179.220-24 Transportation Other Regulations Relating to Transportation (Continued) PIPELINE AND... pressure relief valves. Each safety relief valve must be tested by air or gas for compliance with §...

  7. 49 CFR 179.220-24 - Tests of pressure relief valves.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 3 2012-10-01 2012-10-01 false Tests of pressure relief valves. 179.220-24 Section 179.220-24 Transportation Other Regulations Relating to Transportation (Continued) PIPELINE AND... pressure relief valves. Each safety relief valve must be tested by air or gas for compliance with §...

  8. 49 CFR 179.200-23 - Tests of pressure relief valves.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 3 2012-10-01 2012-10-01 false Tests of pressure relief valves. 179.200-23 Section 179.200-23 Transportation Other Regulations Relating to Transportation (Continued) PIPELINE AND... pressure relief valves. (a) Each valve shall be tested by air or gas for compliance with § 179.15...

  9. 40 CFR 53.56 - Test for effect of variations in ambient pressure.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... to exceed 5 minutes. (5) Flow measurement adaptor (40 CFR part 50, appendix L, figure L-30) or... section 6 of 40 CFR part 50, appendix L (if required). (d) Calibration of test measurement instruments... variations in ambient (barometric) pressure. Tests shall be conducted in a pressure-controlled...

  10. 40 CFR 53.56 - Test for effect of variations in ambient pressure.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... to exceed 5 minutes. (5) Flow measurement adaptor (40 CFR part 50, appendix L, figure L-30) or... section 6 of 40 CFR part 50, appendix L (if required). (d) Calibration of test measurement instruments... variations in ambient (barometric) pressure. Tests shall be conducted in a pressure-controlled...

  11. 40 CFR 53.56 - Test for effect of variations in ambient pressure.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... to exceed 5 minutes. (5) Flow measurement adaptor (40 CFR part 50, appendix L, figure L-30) or... section 6 of 40 CFR part 50, appendix L (if required). (d) Calibration of test measurement instruments... variations in ambient (barometric) pressure. Tests shall be conducted in a pressure-controlled...

  12. Pressurized Testing of Solid Oxide Electrolysis Stacks with Advanced Electrode-Supported Cells

    SciTech Connect

    J. E. O'Brien; X. Zhang; G. K. Housley; K. DeWall; L. Moore-McAteer; G. Tao

    2012-06-01

    A new facility has been developed at the Idaho National Laboratory for pressurized testing of solid oxide electrolysis stacks. Pressurized operation is envisioned for large-scale hydrogen production plants, yielding higher overall efficiencies when the hydrogen product is to be delivered at elevated pressure for tank storage or pipelines. Pressurized operation also supports higher mass flow rates of the process gases with smaller components. The test stand can accommodate cell dimensions up to 8.5 cm x 8.5 cm and stacks of up to 25 cells. The pressure boundary for these tests is a water-cooled spool-piece pressure vessel designed for operation up to 5 MPa. The stack is internally manifolded and operates in cross-flow with an inverted-U flow pattern. Feed-throughs for gas inlets/outlets, power, and instrumentation are all located in the bottom flange. The entire spool piece, with the exception of the bottom flange, can be lifted to allow access to the internal furnace and test fixture. Lifting is accomplished with a motorized threaded drive mechanism attached to a rigid structural frame. Stack mechanical compression is accomplished using springs that are located inside of the pressure boundary, but outside of the hot zone. Initial stack heatup and performance characterization occurs at ambient pressure followed by lowering and sealing of the pressure vessel and subsequent pressurization. Pressure equalization between the anode and cathode sides of the cells and the stack surroundings is ensured by combining all of the process gases downstream of the stack. Steady pressure is maintained by means of a backpressure regulator and a digital pressure controller. A full description of the pressurized test apparatus is provided in this paper.

  13. Pressure control and analysis report: Hydrogen Thermal Test Article (HTTA)

    NASA Technical Reports Server (NTRS)

    1971-01-01

    Tasks accomplished during the HTTA Program study period included: (1) performance of a literature review to provide system guidelines; (2) development of analytical procedures needed to predict system performance; (3) design and analysis of the HTTA pressurization system considering (a) future utilization of results in the design of a spacecraft maneuvering system propellant package, (b) ease of control and operation, (c) system safety, and (d) hardware cost; and (4) making conclusions and recommendations for systems design.

  14. An experimental method to dynamically test pressure sensors using a rupture disk

    NASA Astrophysics Data System (ADS)

    Liu, Hanying; Miller, Don W.; Talnagi, Joseph W.

    2002-02-01

    The response time of a pressure sensor is required when it is used in control systems and in some measurement applications. It is often difficult to measure the response time of a pressure sensor since it is difficult to obtain changes in fluid pressure sufficient to characterize the sensor dynamic response. In this article we describe a relatively simple system for measuring or validating the response time of pressure sensors with fast dynamic response. The system consists of two chambers isolated by a graphite rupture disk, a device that fully and rapidly opens at a known rupture or break pressure. A pressure transient in the second chamber is initiated by slowly increasing the pressure in the first chamber until reaching the nominal break pressure of the rupture disk. Performance of the system was validated by comparing the rise time predicted by a theoretical model with the rise time of the pressure transient measured by a piezoelectric pressure transducer. The method was evaluated by comparing the response to the pressure transient of an optical based pressure transducer with the response of the reference piezoelectric pressure transducer. The time constant of the tested fiber optic pressure sensor was found using the method presented in this article to be 0.488 ms, which is close to the time constant of 0.455 ms measured by a comparison method.

  15. Teledyne Taber 206-1000 and 2210-3000 pressure transducer proof test and burst test

    NASA Technical Reports Server (NTRS)

    Ricks, G. A.

    1989-01-01

    The range accuracy and structural integrity of the Teledyne Taber 206-1000 and 2210-3000 pressure transducers are verified and multiple uses are studied to determine is they have a significant effect on the transducers. Burst pressure for these transducers was also established. The Teledyne Taber 206-1000 pressure transducer is used to measure chamber pressure on full-scale space shuttle rocket motors. The Teledyne Taber 2210-3000 pressure transducer is used to measure igniter pressure. The Teledyne Taber transducer has very good temperature stability and was used on all full-scale solid rocket motors, so there is a large data base established using this transducer.

  16. Condenser performance test and back-pressure improvement: Final report

    SciTech Connect

    Piskorowski, J.; Beckett, G.; Bell, R.

    1988-04-01

    This document describes condenser performance test and analyses experiences. The testing was performed by Indianapolis Power and Light Company (IPL) on the Petersburg Unit 3 condenser. The initial testing revealed a performance deficiency. Modifications were made to the condenser, air in-leakage was reduced and the vacuum pumps were brought back to their original design capacity. Testing was reperformed after these activities and although a significant performance improvement was achieved deficiencies were still evident. Heat Exchanger Systems, Inc. (HES) was retained as consultants during this testing program. The Central Electricity Generating Board's (CEGB) Central Electricity Research Laboratory (CERL) acting as a subcontractor to HES were retained to perform an analysis of the Petersburg Unit 3 condenser using their EPOC computer code. The results of this analysis are also contained in this document. 3 refs., 48 figs., 3 tabs.

  17. Analysis, design and testing of high pressure waterjet nozzles

    NASA Technical Reports Server (NTRS)

    Mazzoleni, Andre P.

    1996-01-01

    The Hydroblast Research Cell at MSFC is both a research and a processing facility. The cell is used to investigate fundamental phenomena associated with waterjets as well as to clean hardware for various NASA and contractor projects. In the area of research, investigations are made regarding the use of high pressure waterjets to strip paint, grease, adhesive and thermal spray coatings from various substrates. Current industrial methods of cleaning often use ozone depleting chemicals (ODC) such as chlorinated solvents, and high pressure waterjet cleaning has proven to be a viable alternative. Standard methods of waterjet cleaning use hand held or robotically controlled nozzles. The nozzles used can be single-stream or multijet nozzles, and the multijet nozzles may be mounted in a rotating head or arranged in a fan-type shape. We consider in this paper the use of a rotating, multijet, high pressure water nozzle which is robotically controlled. This method enables rapid cleaning of a large area, but problems such as incomplete coverage (e.g. the formation of 'islands' of material not cleaned) and damage to the substrate from the waterjet have been observed. In addition, current stripping operations require the nozzle to be placed at a standoff distance of approximately 2 inches in order to achieve adequate performance. This close proximity of the nozzle to the target to be cleaned poses risks to the nozzle and the target in the event of robot error or the striking of unanticipated extrusions on the target surface as the nozzle sweeps past. Two key motivations of this research are to eliminate the formation of 'coating islands' and to increase the allowable standoff distance of the nozzle.

  18. Evaluation of high pressure water blast with rotating spray bar for removing paint and rubber deposits from airport runways, and review of runway slipperiness problems created by rubber contamination

    NASA Technical Reports Server (NTRS)

    Horne, W. B.; Griswold, G. D.

    1975-01-01

    A high pressure water blast with rotating spray bar treatment for removing paint and rubber deposits from airport runways is studied. The results of the evaluation suggest that the treatment is very effective in removing above surface paint and rubber deposits to the point that pavement skid resistance is restored to trafficked but uncontaminated runway surface skid resistance levels. Aircraft operating problems created by runway slipperiness are reviewed along with an assessment of the contributions that pavement surface treatments, surface weathering, traffic polishing, and rubber deposits make in creating or alleviating runway slipperiness. The results suggest that conventional surface treatments for both portland cement and asphaltic concrete runways are extremely vulnerable to rubber deposit accretions which can produce runway slipperiness conditions for aircraft operations as or more slippery than many snow and ice-covered runway conditions. Pavement grooving surface treatments are shown to be the least vulnerable to rubber deposits accretion and traffic polishing of the surface treatments examined.

  19. Device for testing closure disks at high rates of change of pressure

    DOEpatents

    Merten, C.W. Jr.

    1993-11-09

    A device is described for testing the burst pressure of closure disks which provides high pressure to both sides of a disk and rapidly releases pressure from one side thereof causing a high rate of change of pressure. A hollow notched plug allows the rapid release of pressure upon rupturing. A means is also disclosed for transmitting a tensile load from a piston to a hollow notched plug and for sealing the means for transmitting load within a hole in a piston. 5 figures.

  20. The B.A.R. Demonstration Project: A Comparative Evaluation Trial of Computer-Based, Multimedia Simulation Testing and "Hands-on," Actual Equipment Testing.

    ERIC Educational Resources Information Center

    Maher, Thomas G.

    A general evaluation design was developed to examine the effectiveness of a computer-based, multimedia simulation test on California smog check mechanics. The simulation test operated on an Apple Macintosh IIci, with a single touchscreen color monitor controlling a videodisc player; it had three parts: introduction-tutorial-help, data, and test.…

  1. Subsurface fluid pressures from drill-stem tests, Uinta Basin, Utah

    USGS Publications Warehouse

    Nelson, P.H.

    2002-01-01

    High fluid pressures are known to be associated with oil and gas fields in the Uinta Basin, Utah. Shut-in pressure measurements from drill-stem tests show how pressure varies with depth and by area within the basin. The data base used in this report incorporates over 2,000 pressure measurements from drill-stem tests in wells completed prior to 1985. However, the number of useful pressure measurements is considerably less, because many drill-stem tests fail to stabilize at the actual formation pressure if the permeability is low. By extracting the maximum pressure measurements recorded in a collection of wells within an area, the trend of formation pressure within that area can be approximated. Areal compilations of pressures from drill-stem tests show that overpressured rock formations occur throughout much of the northern and eastern areas of the Uinta Basin. In particular, significant overpressuring (0.5 < pressure gradient < 0.8 psi/ft) is found throughout much of the Altamont-Bluebell field at depths ranging from 10,000 to 13,000 ft, equivalent to 5,000 to 8,000 ft below sea level. Limited data indicate that the pressure gradient declines at depths greater than 13,000 ft. An underpressured zone appears to exist in the Altamont-Bluebell field at depths shallower than 5,000 ft. Throughout the eastern Uinta Basin, moderately overpressured zones (0.46 < pressure gradient < 0.5 psi/ft) are common, with local evidence of significantly overpressured zones, but pressure gradients greater than 0.6 psi/ft are rare.

  2. Statistical testing and estimation of uncertainty in pre-post case control experimental designs: are the error bars of physics too large?

    NASA Astrophysics Data System (ADS)

    Ignatius, K.; Henning, S.; Stratmann, F.

    2013-12-01

    We encountered the question of how to do statistical inference and uncertainty estimation for the aerosol particle hygroscopicity (κ) measured up- and downstream of a hilltop in two conditions: during full-cloud events (FCE) where a cap cloud was present on the hilltop, and under cloud-free conditions (non-cloud events, NCE). The aim was to show with statistical testing that particle hygroscopicity is altered by cloud processing. This type of statistical experimental design known as a 'pre-post case control study', 'between-within design' or 'mixed design' is common in medicine and biostatistics but it may not be familiar to all researchers in the atmospheric sciences. Therefore we review the statistical testing methods that can be applied to solve these kind of problems. The key point is that these methods use the pre-measurement as a covariate to the post-measurement, which accounts for the daily variation and reduces variance in the analysis. All the three tests, Change score analysis, Analysis of Covariance (ANCOVA) and multi-way Analysis of Variance (ANOVA) gave similar results and suggested a statistically significant change in κ between FCE and NCE. Quantification of the uncertainty in hygroscopicities derived from cloud condensation nuclei (CCN) measurements implies an uncertainty interval estimation in a nonlinear expression where the uncertainty of one parameter is Gaussian with known mean and variance. We concluded that the commonly used way of estimating and showing the uncertainty intervals in hygroscopicity studies may make the error bars appear too large. Using simple Monte Carlo sampling and plotting the resulting nonlinear distribution and its quantiles may better represent the probability mass in the uncertainty distribution.

  3. No-vent fill pressurization tests using a cryogen simulant

    NASA Technical Reports Server (NTRS)

    Schmidt, G. R.; Carrigan, R. W.; Hahs, J. E.; Vaughan, D. A.; Foust, D. C.

    1991-01-01

    The results are described of an experimental program which studied the performance of various no-vent fill techniques for tank-to-tank liquid transfer. The tests were performed using a cryogen simulant (Freon-114) and a test bed consisting of a multiple tank/plumbing network that enabled studies of a variety of different inlet flow and active mixing regimes. Several results and conclusions were drawn from the 26 transfer experiments comprising the program. Most notable was the significant improvement in fill performance (i.e., minimized fill time and maximized fill fraction) with increased agitation of the liquid surface. Another was the close correlation between measured condensation rates and those predicted by recent theories which express condensation as a function of turbulent eddy effects on the liquid surface. In most cases, test data exhibited strong agreement with an analytical model which accounts for tank heat transfer and thermodynamics in a 1 g environment.

  4. No-vent fill pressurization tests using a cryogen simulant

    NASA Technical Reports Server (NTRS)

    Schmidt, G.; Carrigan, R.; Hahs, J.; Vaughan, D.; Foust, D.

    1992-01-01

    The results are described of an experimental program which studied the performance of various no-vent fill techniques for tank-to-tank liquid transfer. The tests were performed using a cryogen simulant (Freon-114) and a test bed consisting of a multiple tank/plumbing network that enabled studies of a variety of different inlet flow and active mixing regimes. Several results and conclusions were drawn from the 26 transfer experiments comprising the program. Most notable was the significant improvement in fill performance (i.e., minimized fill time and maximized fill fraction) with increased agitation of the liquid surface. Another was the close correlation between measured condensation rates and those predicted by recent theories which express condensation as a function of turbulent eddy effects on the liquid surface. In most cases, test data exhibited strong agreement with an analytical model which accounts for tank heat transfer and thermodynamics in a 1 g environment.

  5. Performance Evaluation Tests of Insulated Pressure Vessels for Vehicular Hydrogen Storage

    SciTech Connect

    Aceves, S M; Martinez-Frias, J; Espinoza-Loza, F

    2002-03-01

    Insulated pressure vessels are cryogenic-capable pressure vessels that can be fueled with liquid hydrogen or ambient-temperature compressed hydrogen. This flexibility results in multiple advantages with respect to compressed hydrogen tanks or low-pressure liquid hydrogen tanks. Our work is directed at verifying that commercially available aluminum-lined, fiber-wrapped pressure vessels can be safely used to store liquid hydrogen. A series of tests have been conducted, and the results indicate that no significant vessel damage has resulted from cryogenic operation. Future activities include a demonstration project in which the insulated pressure vessels will be installed and tested on two vehicles. A draft standard will also be generated for certification of insulated pressure vessels.

  6. Certification Testing and Demonstration of Insulated Pressure Vessels for Vehicular Hydrogen Storage

    SciTech Connect

    Aceves, S M; Martinez-Frias, J; Espinosa-Loza, F

    2002-05-22

    Insulated pressure vessels are cryogenic-capable pressure vessels that can be fueled with liquid hydrogen or ambient-temperature compressed hydrogen. This flexibility results in multiple advantages with respect to compressed hydrogen tanks or low-pressure liquid hydrogen tanks. Our work is directed at verifying that commercially available aluminum-lined, fiber-wrapped pressure vessels can be safely used to store liquid hydrogen. A series of tests have been conducted, and the results indicate that no significant vessel damage has resulted from cryogenic operation. Future activities include a demonstration project in which the insulated pressure vessels will be installed and tested on two vehicles. A draft standard will also be generated for certification of insulated pressure vessels.

  7. Study and application of a high-pressure water jet multi-functional flow test system

    NASA Astrophysics Data System (ADS)

    Shi, Huaizhong; Li, Gensheng; Huang, Zhongwei; Li, Jingbin; Zhang, Yi

    2015-12-01

    As the exploration and development of oil and gas focus more and more on deeper formation, hydraulic issues such as high-pressure water jet rock breaking, wellbore multiphase flow law, cuttings carrying efficiency, and hydraulic fracturing technique during the drilling and completion process have become the key points. To accomplish related researches, a high-pressure water jet multi-functional flow test system was designed. The following novel researches are carried out: study of high-pressure water jet characteristics under confining pressure, wellbore multiphase flow regime, hydraulic pressure properties of down hole tools during jet fracturing and pulsed cavitation jet drilling, and deflector's friction in radial jet drilling. The validity and feasibility of the experimental results provided by the system with various test modules have proved its importance in the research of the high-pressure water jet and well completion technology.

  8. Study and application of a high-pressure water jet multi-functional flow test system.

    PubMed

    Shi, Huaizhong; Li, Gensheng; Huang, Zhongwei; Li, Jingbin; Zhang, Yi

    2015-12-01

    As the exploration and development of oil and gas focus more and more on deeper formation, hydraulic issues such as high-pressure water jet rock breaking, wellbore multiphase flow law, cuttings carrying efficiency, and hydraulic fracturing technique during the drilling and completion process have become the key points. To accomplish related researches, a high-pressure water jet multi-functional flow test system was designed. The following novel researches are carried out: study of high-pressure water jet characteristics under confining pressure, wellbore multiphase flow regime, hydraulic pressure properties of down hole tools during jet fracturing and pulsed cavitation jet drilling, and deflector's friction in radial jet drilling. The validity and feasibility of the experimental results provided by the system with various test modules have proved its importance in the research of the high-pressure water jet and well completion technology. PMID:26724077

  9. Cygnus Pressurized Cargo Module (PCM) Flight Inertial Load Static Tests

    NASA Astrophysics Data System (ADS)

    Murgia, Giovanni; Mancini, Simone; Palmieri, Paolo; Rutigliano, Luigi

    2012-07-01

    Cygnus PCM Flight Inertial Load Static Test campaign has been performed by Thales Alenia Space - Italy (TAS-I) to achieve the Static Qualification of its Primary Structure. A “Proto-flight Approach” has been followed (as per [1] and [2]), thus the first flight unit, the PCM0, has been tested up to qualification level (qualification/acceptance factor equivalent to 1.2 [1]). The PCM0 has been constrained to a dummy Service Module (the second member of Cygnus Spacecraft), representative in terms of interfaces provisions, and flight load conditions have been reproduced with proper forces that have been applied by means of hydraulic jacks at internal PCM secondary structure interfaces. Test load cases have been defined in order to simulate load paths and relevant stress fields associated to the worst flight load conditions by using the FE model analyses. Tests have been monitored by means of gauges and displacement transducers and results have been utilized to correlate the PCM FEM following [3] requirements.

  10. Implications of Dynamic Pressure Transducer Mounting Variations on Measurements in Pyrotechnic Test Apparatus

    NASA Technical Reports Server (NTRS)

    Dibbern, Andreas; Crisafulli, Jeffrey; Hagopia, Michael; McDougle, Stephen H.; Saulsberry, Regor L.

    2009-01-01

    Accurate dynamic pressure measurements are often difficult to make within small pyrotechnic devices, and transducer mounting difficulties can cause data anomalies that lead to erroneous conclusions. Delayed initial pressure response followed by data ringing has been observed when using miniaturized pressure transducer mounting adapters required to interface transducers to small test chambers. This delayed pressure response and ringing, combined with a high data acquisition rate, has complicated data analysis. This paper compares the output signal characteristics from different pressure transducer mounting options, where the passage distance from the transducer face to the pyrotechnic chamber is varied in length and diameter. By analyzing the data and understating the associated system dynamics, a more realistic understanding of the actual dynamic pressure variations is achieved. Three pressure transducer mounting configurations (elongated, standard, and face/flush mount) were simultaneously tested using NASA standard initiators in closed volume pressure bombs. This paper also presents results of these pressure transducer mounting configurations as a result of a larger NASA Engineering and Safety Center pyrovalve test project. Results from these tests indicate the improved performance of using face/flush mounted pressure transducers in this application. This type of mounting improved initial pressure measurement response time by approximately 19 s over standard adapter mounting, eliminating most of the lag time; provided a near step-function type initial pressure increase; and greatly reduced data ringing in high data acquisition rate systems. The paper goes on to discuss other issues associated with the firing and instrumentation that are important for the tester to understand.

  11. Tests of models equipped with TPS in low speed ONERA F1 pressurized wind tunnel

    NASA Astrophysics Data System (ADS)

    Leynaert, J.

    1992-09-01

    The particular conditions of tests of models equipped with a turbofan powered simulator (TPS) at high Reynolds numbers in a pressurized wind tunnel are presented. The high-pressure air supply system of the wind tunnel, the equipment of the balance with the high-pressure traversing flow and its calibration, and the thrust calibration method of the TPS and its verification in the wind tunnel are described.

  12. Data acquisition and interpretation of horizontal well pressure-transient tests

    SciTech Connect

    Lichtenberger, G.J. )

    1994-02-01

    For both vertical and horizontal wells, pressure-transient testing is a powerful tool for evaluating in-situ reservoir and wellbore parameters that describe the production characteristics of a well. Although many operators use horizontal well technology, many engineers consider pressure-transient testing of horizontal wells impractical and too complex. Experience has shown, however, that with adequate test planning, based on the concept of low regimes and focused on optimizing test conditions, horizontal well testing can be as successful as vertical well testing. Using the concept of flow regimes and drawing on analogies with vertical wells, this paper reviews the pressure-transient behavior of horizontal wells. Practical guidelines are given for planning, executing, and interpreting horizontal well tests. The application of various interpretation techniques is illustrated with field examples.

  13. Small, high-pressure ratio compressor mechanical acceptance test, volume 2

    NASA Technical Reports Server (NTRS)

    Metty, G. R.; Shoup, W. I.

    1973-01-01

    The fabrication and mechanical testing of the high-pressure-ratio compressor are reported. Mechanical testing was performed to demonstrate overspeed capability, adequate rotor dynamics, electrical isolation of the gas bearing trunnion mounted diffuser and shroud and the effect of operating parameters (speed and pressure ratio) on clearance of the compressor test rig. The speed range covered was 20 to 120 percent of rated speed (80,000 rpm). Following these tests an acceptance test which consisted of a 5 hour run at 80,000 rpm was made with approximately design impeller to shroud clearances. For Vol. 1, see N73-26483.

  14. The four bars problem

    NASA Astrophysics Data System (ADS)

    Mauroy, Alexandre; Taslakian, Perouz; Langerman, Stefan; Jungers, Raphaël

    2016-09-01

    A four-bar linkage is a mechanism consisting of four rigid bars which are joined by their endpoints in a polygonal chain and which can rotate freely at the joints (or vertices). We assume that the linkage lies in the 2-dimensional plane so that one of the bars is held horizontally fixed. In this paper we consider the problem of reconfiguring a four-bar linkage using an operation called a pop. Given a four-bar linkage, a pop reflects a vertex across the line defined by its two adjacent vertices along the polygonal chain. Our main result shows that for certain conditions on the lengths of the bars, the neighborhood of any configuration that can be reached by smooth motion can also be reached by pops. The proof relies on the fact that pops are described by a map on the circle with an irrational number of rotation.

  15. Fluid dynamics of a pressure measuring system for underground explosive tests

    SciTech Connect

    Dykhuizen, R.C.

    1987-01-01

    Numerical and analytical models are used to optimize a pressure measuring system for underground nuclear tests. This system uses a long pipe filled with gas to communicate the pressure level to a transducer in a pressure chamber remote from the explosion cavity. The pressure chamber and pipe are pressurized above the final pressure expected from the explosion. During the explosion, the high pressure gas blows down, preventing debris from entering and clogging the system. The models were first checked against the Junior Jade test series, which used an undergound non-nuclear explosion to simulate a nuclear test. It was found that the measured pressure oscillated for some time before settling down to a steady value. This is shown to be a result of an organ pipe oscillation that can develop in the short pipes used for this test series. The analytical model provided a simple means to optimize the system design parameters and showed that changing the working fluid from nitrogen to helium would improve the time response of the system significantly. The numerical model is then used to obtain more accurate predictions of the sytem response. 2 refs., 5 figs., 1 tab.

  16. Bar Code Labels

    NASA Technical Reports Server (NTRS)

    1988-01-01

    American Bar Codes, Inc. developed special bar code labels for inventory control of space shuttle parts and other space system components. ABC labels are made in a company-developed anodizing aluminum process and consecutively marketed with bar code symbology and human readable numbers. They offer extreme abrasion resistance and indefinite resistance to ultraviolet radiation, capable of withstanding 700 degree temperatures without deterioration and up to 1400 degrees with special designs. They offer high resistance to salt spray, cleaning fluids and mild acids. ABC is now producing these bar code labels commercially or industrial customers who also need labels to resist harsh environments.

  17. Design certification tests: High Pressure Oxygen Filter (HPOF) program. Summary report

    NASA Technical Reports Server (NTRS)

    Smith, I. D.

    1976-01-01

    Design and acceptance certification test procedures and results are presented for a high pressure oxygen filter developed to protect the sealing surfaces in emergency oxygen systems. Equipment specifications are included.

  18. Highly reliable qcw laser bars and stacks

    NASA Astrophysics Data System (ADS)

    Deichsel, E.; Schröder, D.; Meusel, J.; Hülsewede, R.; Sebastian, J.; Ludwig, S.; Hennig, P.

    2008-02-01

    Based on a well established technology for continuous-wave (cw) diode lasers, further development and optimization lead to high performance laser bars for quasi-continuous-wave (qcw) operation suitable for pumping applications. Mounted on standard heat sinks, these 808nm laser bars exhibit more than 300W (400W) qcw output power with 50% (75%) filling factors. Reliability tests of these bars are running at >200W. Several GShots at 2, 4 and 10% duty cycle (d.c.) were already achieved. With this high performance qcw laser bars, passively cooled laser stacks were developed and tested using a new design compatible to high power operation. Thermal expansion matched materials and hard solder techniques allow reliable operation, even under rough environmental conditions. Output powers of 2.5kW (>300W per bar) were demonstrated from a stack with 8 bars. After environmental tests (vibration and thermal cycles), an ongoing life test exhibits more than 2.5GShots with 1.6kW (~200W per bar) at 4% duty cycle.

  19. Activation of the E1 Ultra High Pressure Propulsion Test Facility at Stennis Space Center

    NASA Technical Reports Server (NTRS)

    Messer, Bradley; Messer, Elisabeth; Sewell, Dale; Sass, Jared; Lott, Jeff; Dutreix, Lionel, III

    2001-01-01

    After a decade of construction and a year of activation the El Ultra High Pressure Propulsion Test Facility at NASA's Stennis Space Center is fully operational. The El UHP Propulsion Test Facility is a multi-cell, multi-purpose component and engine test facility . The facility is capable of delivering cryogenic propellants at low, high, and ultra high pressures with flow rates ranging from a few pounds per second up to two thousand pounds per second. Facility activation is defined as a series of tasks required to transition between completion of construction and facility operational readiness. Activating the El UHP Propulsion Test Facility involved independent system checkouts, propellant system leak checks, fluid and gas sampling, gaseous system blow downs, pressurization and vent system checkouts, valve stability testing, valve tuning cryogenic cold flows, and functional readiness tests.

  20. Space Station Freedom delta pressure leakage rate comparison test data analysis report

    NASA Technical Reports Server (NTRS)

    Sorensen, E. B.

    1992-01-01

    Results are provided of a series of tests performed to identify the relationship between gas leakage rates across a seal at various internal to external pressure ratios. The results complement and provide insight into the analysis technique used to obtain the results presented in MSFC SSF/DEV/EL91-008, 'Space Station Freedom (S.S. Freedom) Seal Flaw Study with Delta Pressure Leak Rate Comparison Test Report.'

  1. The BaBar electromagnetic calorimeter

    SciTech Connect

    Stahl, A.

    1997-07-01

    The progress on the design and construction of the BaBar electromagnetic calorimeter including its mechanical structure, the readout system, the mechanical and optical properties of the crystals, and the schedule for the final assembly and testing is summarized.

  2. Multilayer Pressure Vessel Materials Testing and Analysis Phase 2

    NASA Technical Reports Server (NTRS)

    Popelar, Carl F.; Cardinal, Joseph W.

    2014-01-01

    To provide NASA with a suite of materials strength, fracture toughness and crack growth rate test results for use in remaining life calculations for the vessels described above, Southwest Research Institute® (SwRI®) was contracted in two phases to obtain relevant material property data from a representative vessel. An initial characterization of the strength, fracture and fatigue crack growth properties was performed in Phase 1. Based on the results and recommendations of Phase 1, a more extensive material property characterization effort was developed in this Phase 2 effort. This Phase 2 characterization included additional strength, fracture and fatigue crack growth of the multilayer vessel and head materials. In addition, some more limited characterization of the welds and heat affected zones (HAZs) were performed. This report

  3. Performance and Certification Testing of Insulated Pressure Vessels for Vehicular Hydrogen Storage

    SciTech Connect

    Aceves, S M; Martinez-Frias, J; Garcia-Villazana, O; Espinosa-Loza, F

    2001-06-03

    Insulated pressure vessels are cryogenic-capable pressure vessels that can be fueled with liquid hydrogen (LH2) or ambient-temperature compressed hydrogen (CH2). Insulated pressure vessels offer the advantages of liquid hydrogen tanks (low weight and volume), with reduced disadvantages (fuel flexibility, lower energy requirement for hydrogen liquefaction and reduced evaporative losses). The work described here is directed at verifying that commercially available pressure vessels can be safely used to store liquid hydrogen. The use of commercially available pressure vessels significantly reduces the cost and complexity of the insulated pressure vessel development effort. This paper describes a series of tests that have been done with aluminum-lined, fiber-wrapped vessels to evaluate the damage caused by low temperature operation. All analysis and experiments to date indicate that no significant damage has resulted. Required future tests are described that will prove that no technical barriers exist to the safe use of aluminum-fiber vessels at cryogenic temperatures. Future activities also include a demonstration project in which the insulated pressure vessels will be installed and tested on two vehicles. A draft standard will also be generated for obtaining certification for insulated pressure vessels.

  4. Certification Testing and Demonstration of Insulated Pressure Vessels for Vehicular Hydrogen and Natural Gas Storage

    SciTech Connect

    Aceves, S M; Martinez-Frias, J; Espinosa-Loza, F; Schaffer, R; Clapper, W

    2002-05-22

    We are working on developing an alternative technology for storage of hydrogen or natural gas on light-duty vehicles. This technology has been titled insulated pressure vessels. Insulated pressure vessels are cryogenic-capable pressure vessels that can accept either liquid fuel or ambient-temperature compressed fuel. Insulated pressure vessels offer the advantages of cryogenic liquid fuel tanks (low weight and volume), with reduced disadvantages (fuel flexibility, lower energy requirement for fuel liquefaction and reduced evaporative losses). The work described in this paper is directed at verifying that commercially available pressure vessels can be safely used to store liquid hydrogen or LNG. The use of commercially available pressure vessels significantly reduces the cost and complexity of the insulated pressure vessel development effort. This paper describes a series of tests that have been done with aluminum-lined, fiber-wrapped vessels to evaluate the damage caused by low temperature operation. All analysis and experiments to date indicate that no significant damage has resulted. Future activities include a demonstration project in which the insulated pressure vessels will be installed and tested on two vehicles. A draft standard will also be generated for obtaining insulated pressure vessel certification.

  5. Energy efficient engine low-pressure compressor component test hardware detailed design report

    NASA Technical Reports Server (NTRS)

    Michael, C. J.; Halle, J. E.

    1981-01-01

    The aerodynamic and mechanical design description of the low pressure compressor component of the Energy Efficient Engine were used. The component was designed to meet the requirements of the Flight Propulsion System while maintaining a low cost approach in providing a low pressure compressor design for the Integrated Core/Low Spool test required in the Energy Efficient Engine Program. The resulting low pressure compressor component design meets or exceeds all design goals with the exception of surge margin. In addition, the expense of hardware fabrication for the Integrated Core/Low Spool test has been minimized through the use of existing minor part hardware.

  6. Design, analysis, and fabrication of a pressure box test fixture for tension damage tolerance testing of curved fuselage panels

    NASA Technical Reports Server (NTRS)

    Smith, P. J.; Bodine, J. B.; Preuss, C. H.; Koch, W. J.

    1993-01-01

    A pressure box test fixture was designed and fabricated to evaluate the effects of internal pressure, biaxial tension loads, curvature, and damage on the fracture response of composite fuselage structure. Previous work in composite fuselage tension damage tolerance, performed during NASA contract NAS1-17740, evaluated the above effects on unstiffened panels only. This work extends the tension damage tolerance testing to curved stiffened fuselage crown structure that contains longitudinal stringers and circumferential frame elements. The pressure box fixture was designed to apply internal pressure up to 20 psi, and axial tension loads up to 5000 lb/in, either separately or simultaneously. A NASTRAN finite element model of the pressure box fixture and composite stiffened panel was used to help design the test fixture, and was compared to a finite element model of a full composite stiffened fuselage shell. This was done to ensure that the test panel was loaded in a similar way to a panel in the full fuselage shell, and that the fixture and its attachment plates did not adversely affect the panel.

  7. An evaluation of the pressure proof test concept for thin sheet 2024-T3

    NASA Technical Reports Server (NTRS)

    Dawicke, D. S.; Poe, C. C., Jr.; Newman, James C., Jr.; Harris, Charles E.

    1990-01-01

    The concept of pressure proof testing of fuselage structures with fatigue cracks to insure structural integrity was evaluated from a fracture mechanics viewpoint. A generic analytical and experimental investigation was conducted on uniaxially loaded flat panels with crack configurations and stress levels typical of longitudinal lap splice joints in commercial transport aircraft fuselages. The results revealed that the remaining fatigue life after a proof test was longer than that without the proof test because of crack growth retardation due to increased crack closure. However, based on a crack length that is slightly less than the critical value at the maximum proof test stress, the minimum assured life or proof test interval must be no more than 550 pressure cycles for a 1.33 proof factor and 1530 pressure cycles for a 1.5 proof factor to prevent in-flight failures.

  8. An evaluation of the pressure proof test concept for thin sheet 2024-T3

    NASA Technical Reports Server (NTRS)

    Dawicke, D. S.; Poe, C. C., Jr.; Newman, J. C., Jr.; Harris, C. E.

    1990-01-01

    The concept of pressure proof testing of fuselage structures with fatigue cracks to insure structural integrity was evaluated from a fracture mechanics viewpoint. A generic analytical and experimental investigation was conducted on uniaxially loaded flat panels with crack configurations and stress levels typical of longitudinal lap-splice joints in commercial transport aircraft fuselage. The results revealed that the remaining fatigue life after a proof test was longer than that without the proof test because of crack growth retardation due to increased crack closure. However, based on a crack length that is slightly less than the critical value at the maximum proof test stress, the minimum assured life or proof test interval must be no more than 550 pressure cycles for a 1.33 proof factor and 1530 pressure cycles for a 1.5 proof factor to prevent in-flight failures.

  9. Bar-biting

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Bar biting is regarded as a stereotypic behavior in which the animal carries out repetitive mouthing and biting of the metal bars in its environmental enclosure. It is commonly seen in sows housed in close confinement, in barren environments, and with restricted access to food. However, it has also ...

  10. Elastic-plastic failure analysis of pressure burst tests of thin toroidal shells

    SciTech Connect

    Jones, D.P.; Holliday, J.E.; Larson, L.D.

    1998-07-01

    This paper provides a comparison between test and analysis results for bursting of thin toroidal shells. Testing was done by pressurizing two toroidal shells until failure by bursting. An analytical criterion for bursting is developed based on good agreement between structural instability predicted by large strain-large displacement elastic-plastic finite element analysis and observed burst pressure obtained from test. The failures were characterized by loss of local stability of the membrane section of the shells consistent with the predictions from the finite element analysis. Good agreement between measured and predicted burst pressure suggests that incipient structural instability as calculated by an elastic-plastic finite element analysis is a reasonable way to calculate the bursting pressure of thin membrane structures.

  11. Testing of a 4 K to 2 K heat exchanger with an intermediate pressure drop

    SciTech Connect

    Knudsen, Peter N.; Ganni, Venkatarao

    2015-12-01

    Most large sub-atmospheric helium refrigeration systems incorporate a heat exchanger at the load, or in the distribution system, to counter-flow the sub-atmospheric return with the super-critical or liquid supply. A significant process improvement is theoretically obtainable by handling the exergy loss across the Joule-Thompson throttling valve supplying the flow to the load in a simple but different manner. As briefly outlined in previous publications, the exergy loss can be minimized by allowing the supply flow pressure to decrease to a sub-atmospheric pressure concurrent with heat exchange flow from the load. One practical implementation is to sub-divide the supply flow pressure drop between two heat exchanger sections, incorporating an intermediate pressure drop. Such a test is being performed at Jefferson Lab's Cryogenic Test Facility (CTF). This paper will briefly discuss the theory, practical implementation and test results and analysis obtained to date.

  12. Results of 1.0-L sample bottle pressurization tests for the pit burst experiment

    SciTech Connect

    Veirs, K.D.; Prenger, F.C.; Harradine, D.M.; McFarlan, J.T.

    1997-02-01

    Pressurization tests were performed on a 1.0-L sample bottle to verify operational aspects of the pit burst experimental test apparatus. The 1.0-L sample bottle was selected because of its known geometry, certified performance and ready availability. Redundant strain gage instrumentation was installed on the test sample enabling evaluation of the repeatability and consistency of data acquisition. Test results were compared with analytical model predictions to evaluate instrumentation accuracy.

  13. Development of immersion quenching of small diameter bars

    SciTech Connect

    Bunte, C.

    1996-12-31

    A change of process in the quenching of 25.40 mm (1 inch) bars in UNI41Cr4 (SAE 5140) was implemented. The change consisted in the passage from induction quenching to immersion quenching in a polymer solution bath. The tests were made on bars of 6.00 meters long, disposed in separate layers. The results were satisfactory: (a) A good homogeneity in the average center hardness of bars. (b) Low distortion of bars. (c) No cracks were found. Afterwards, tests were made on longer bars (9.50 meters) with the same results. This change of process allowed an important reduction of fabrication costs.

  14. Suitport Feasibility: Development and Test of a Suitport and Space Suit for Human Pressurized Space Suit Donning Tests

    NASA Technical Reports Server (NTRS)

    Boyle, Robert M.; Mitchell, Kathryn; Allton, Charles; Ju, Hsing

    2012-01-01

    The suitport concept has been recently implemented as part of the small pressurized lunar rover (Currently the Space Exploration vehicle, or SEV) and the Multi-Mission Space Exploration Vehicle (MMSEV) concept demonstrator vehicle. Suitport replaces or augments the traditional airlock function of a spacecraft by providing a bulkhead opening, capture mechanism, and sealing system to allow ingress and egress of a space suit while the space suit remains outside of the pressurized volume of the spacecraft. This presents significant new opportunities to EVA exploration in both microgravity and surface environments. The suitport concept will enable three main improvements in EVA by providing reductions in: pre-EVA time from hours to less than thirty minutes; airlock consumables; contamination returned to the cabin with the EVA crewmember. To date, the first generation suitport has been tested with mockup suits on the rover cabins and pressurized on a bench top engineering unit. The work on the rover cabin has helped define the operational concepts and timelines, and has demonstrated the potential of suitport to save significant amounts of crew time before and after EVAs. The work with the engineering unit has successfully demonstrated the pressurizable seal concept including the ability to seal after the introduction and removal of contamination to the sealing surfaces. Using this experience, a second generation suitport was designed. This second generation suitport has been tested with a space suit prototype on the second generation MMSEV cabin, and testing is planned using the pressure differentials of the spacecraft. Pressurized testing will be performed using the JSC B32 Chamber B, a human rated vacuum chamber. This test will include human rated suitports, a suitport compatible prototype suit, and chamber modifications. This test will bring these three elements together in the first ever pressurized donning of a rear entry suit through a suitport. This paper presents

  15. Ares I Scale Model Acoustic Tests Instrumentation for Acoustic and Pressure Measurements

    NASA Technical Reports Server (NTRS)

    Vargas, Magda B.; Counter, Douglas D.

    2011-01-01

    The Ares I Scale Model Acoustic Test (ASMAT) was a development test performed at the Marshall Space Flight Center (MSFC) East Test Area (ETA) Test Stand 116. The test article included a 5% scale Ares I vehicle model and tower mounted on the Mobile Launcher. Acoustic and pressure data were measured by approximately 200 instruments located throughout the test article. There were four primary ASMAT instrument suites: ignition overpressure (IOP), lift-off acoustics (LOA), ground acoustics (GA), and spatial correlation (SC). Each instrumentation suite incorporated different sensor models which were selected based upon measurement requirements. These requirements included the type of measurement, exposure to the environment, instrumentation check-outs and data acquisition. The sensors were attached to the test article using different mounts and brackets dependent upon the location of the sensor. This presentation addresses the observed effect of the sensors and mounts on the acoustic and pressure measurements.

  16. Slow bars in spiral galaxies

    NASA Astrophysics Data System (ADS)

    Fridman, A. M.; Khoruzhii, O. V.

    2000-11-01

    Here we put forward some arguments in favour of the existence of slow bars. More then a half of spiral galaxies have in their central regions a bar - a structure in the form of triaxial ellipsoid. Historically two models of the bar were developed - those of the so called ``slow'' and ``fast'' bars. In both cases the bar is in some resonance with the galactic disc region near the bar ends - it is the corotation resonance for a fast bar and the inner Lindblad resonance for a slow bar. For the same angular velocity the fast bar would be larger then the slow bar. Alternatively, for the same size the fast bar would have much higher angular velocity, that being the reason for the terminology used. Up till now, the direct measurement of angular velocity of a bar has been an open problem. This is why all arguments on the nature of bar observed in some particular galaxy are inevitably indirect. Despite the fact that the model of slow bars was developed slightly earlier, the main part of attention was focused on the fast bars. Presently many researchers believe in the existence of the fast bars in real galaxies, while discussions on the existence of the slow bars continue so far. In this Letter we demonstrate that the bar detected in the grand design spiral galaxy NGC 157 is the slow bar.

  17. 33 CFR 183.580 - Static pressure test for fuel tanks.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Static pressure test for fuel tanks. 183.580 Section 183.580 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) BOATING SAFETY BOATS AND ASSOCIATED EQUIPMENT Fuel Systems Tests § 183.580...

  18. 33 CFR 183.580 - Static pressure test for fuel tanks.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 2 2011-07-01 2011-07-01 false Static pressure test for fuel tanks. 183.580 Section 183.580 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) BOATING SAFETY BOATS AND ASSOCIATED EQUIPMENT Fuel Systems Tests § 183.580...

  19. 30 CFR 250.447 - When must I pressure test the BOP system?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... casing or a liner. The District Manager may allow you to omit this test if you didn't remove the BOP stack to run the casing string or liner and the required BOP test pressures for the next section of the... which casing strings and liners meet these criteria....

  20. 30 CFR 250.447 - When must I pressure test the BOP system?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... liner. The District Manager may allow you to omit this test if you didn't remove the BOP stack to run the casing string or liner and the required BOP test pressures for the next section of the hole are... casing strings and liners meet these criteria....

  1. 30 CFR 250.447 - When must I pressure test the BOP system?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... liner. The District Manager may allow you to omit this test if you didn't remove the BOP stack to run the casing string or liner and the required BOP test pressures for the next section of the hole are... casing strings and liners meet these criteria....

  2. 30 CFR 250.447 - When must I pressure test the BOP system?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... liner. The District Manager may allow you to omit this test if you didn't remove the BOP stack to run the casing string or liner and the required BOP test pressures for the next section of the hole are... casing strings and liners meet these criteria....

  3. Software Verification and Validation Test Report for the HEPA filter Differential Pressure Fan Interlock System

    SciTech Connect

    ERMI, A.M.

    2000-09-05

    The HEPA Filter Differential Pressure Fan Interlock System PLC ladder logic software was tested using a Software Verification and Validation (V&V) Test Plan as required by the ''Computer Software Quality Assurance Requirements''. The purpose of his document is to report on the results of the software qualification.

  4. Pressure Distribution on a Wing Section with Slotted Flap in Free Flight Tests

    NASA Technical Reports Server (NTRS)

    Kiel, Georg

    1937-01-01

    The pressure distribution was measured in flight on a wing section with a slotted flap for several flap deflections, and the results obtained are presented. The test apparatus and the procedure employed in obtaining the results are also described. A Fieseler type F 5 R airplane was used for the tests.

  5. 40 CFR 53.56 - Test for effect of variations in ambient pressure.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 6 2013-07-01 2013-07-01 false Test for effect of variations in ambient pressure. 53.56 Section 53.56 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) AMBIENT AIR MONITORING REFERENCE AND EQUIVALENT METHODS Procedures for Testing Physical (Design) and...

  6. Microlensing by the galactic bar

    NASA Technical Reports Server (NTRS)

    Zhao, Hongsheng; Spergel, David N.; Rich, R. Michael

    1995-01-01

    We compute the optical depth and duration distribution of microlensing events towrd Baade's window in a model composed of a Galactic disk and a bar. The bar model is a self-consistent dynamical model built out of individual orbits that has been populated to be consistent with the COBE maps of the Galaxy and kinematic observations of the Galactic bulge. We find that most of the lenses are in the bulge with a line-of-sight distance 6.25 kpc (adopting R(sub 0) = 8 kpc). The microlensing optical depth of a 2 x 10(exp 10) solar mass bar plus a truncated disk is (2.2 +/- 0.45) x 10(exp -6), consistent with the large optical depth (3.2 +/- 1.2) x 10(exp -6) found by Udalski et al. (1994). This model optical depth is enhanced over the predictions of axisymmetric models by Kiraga & Paczynski (1994) by slightly more than a factor of 2, since the bar is elongated along the line of sight. The large Einstein radius and small transverse velocity dispersion also predict a longer event duration in the self-consistent bar model than in the Kiraga-Paczynski model. The event rate and duration distribution also depend on the lower mass cutoff of the lens mass function. With a 0.1 solar mass cutoff, five to seven events (depending on the contribution of disk lenses) with a logarithmic mean duration of 20 days are expected for the Optical Gravitational Lensing Experiment (OGLE) according to our model, while Udalski et al. (1994) observed nine events with durations from 8 to 62 days. On the other hand, if most of the lenses are brown dwarfs, our model predicts too many short-duration events. A Kolmogorov-Smirnov test finds only 7% probability for the model with 0.01 solar mass cutoff to be consistent with current data.

  7. Transient Pressure Test Article (TPTA) 1.1 and 1.1A, volume 1

    NASA Technical Reports Server (NTRS)

    Rebells, Clarence A.

    1988-01-01

    This final test report presents the results obtained during the static hot firing and cold-gas high Q tests of the first Transient Pressure Test Article (TPTA) 1.1. The TPTA consisted of field test joints A and B, which were the original RSRM J-insulation configuration, with a metal capture feature. It also consisted of a flight configuration nozzle-to-case test joint (Joint D) with shorter vent slots. Fluorocarbon O-rings were used in all the test joints. The purpose of the TPTA tests is to evaluate and characterize the RSMR field and nozzle-to-case joints under the influence of ignition and strut loads during liftoff anf high Q. All objectives of the cold-gas high Q (TPTA 1.1A) test were met and all measurements were close to predicted values. During the static hot-firing test (TPTA 1.1), the motor was inadvertently plugged by the quench injector plug, making it a more severe test, although no strut loads were applied. The motor was depressurized after approximately 11 min using an auxiliary system, and no anomalies were noted. In the static hot-firing test, pressure was incident on the insulation and the test joint gaps were within the predicted range. During the static hot-firing test, no strut loads were applied because the loading system malfunctioned. For this test, all measurements were within range of similar tests performed without strut loads.

  8. Results From a Pressure Sensitive Paint Test Conducted at the National Transonic Facility on Test 197: The Common Research Model

    NASA Technical Reports Server (NTRS)

    Watkins, A. Neal; Lipford, William E.; Leighty, Bradley D.; Goodman, Kyle Z.; Goad, William K.; Goad, Linda R.

    2011-01-01

    This report will serve to present results of a test of the pressure sensitive paint (PSP) technique on the Common Research Model (CRM). This test was conducted at the National Transonic Facility (NTF) at NASA Langley Research Center. PSP data was collected on several surfaces with the tunnel operating in both cryogenic mode and standard air mode. This report will also outline lessons learned from the test as well as possible approaches to challenges faced in the test that can be applied to later entries.

  9. Results of pressure locking and thermal binding tests of gate valves

    SciTech Connect

    DeWall, K.G.; Watkins, J.C.; McKellar, M.G.; Bramwell, D.

    1998-05-01

    The US Nuclear Regulatory Commission (NRC), Office of Nuclear Regulatory Research, is funding the Idaho National Engineering and Environmental Laboratory (INEEL) in performing research investigating the performance of gate valves subjected to pressure locking and thermal binding conditions. Pressure locking and thermal binding are phenomena that make a closed gate valve difficult to open. Pressure locking can occur when operating sequences or temperature changes cause the pressure of the fluid in the bonnet (and, in most gate valves, between the discs) to be higher than the pressure on the upstream and downstream sides of the disc assembly. Thermal binding can occur when thermal expansion/contraction effects cause the disc to be squeezed between the valve body seats. If the loads associated with pressure locking or thermal binding are very high, the actuator might not have the capacity to open the valve. The authors tested a flexible-wedge gate valve and a double-disc gate valve under pressure locking and thermal binding conditions. The results show that these valves are susceptible to pressure locking; however, they are not significantly affected by thermal binding. For the flexible-wedge gate valve, pressure locking loads (in terms of stem thrust) were higher than corresponding hydrostatic opening loads by a factor of 1.1 to 1.5. For the parallel disc gate valve, pressure locking loads were higher by a factor of 2.05 to 2.4. The results also show that seat leakage affects the bonnet pressurization rate when the valve is subjected to thermally induced pressure locking conditions.

  10. Pressure transient tests on geothermal wells in the Dogger aquifer, Paris Basin

    NASA Astrophysics Data System (ADS)

    giuglaris, elodie; hamm, virginie

    2014-05-01

    In this work, we propose a new interpretation of pressure transient tests conducted in more than sixty wells targeting the Dogger formation in the Paris basin. The most part of these wells were drilled during the eighties over a very short period of time in an urban area. The transient tests were only recorded during a pressure buildup and show that contrary to what has long been assumed the Dogger aquifer behavior is not homogeneous. The interpretation of the obtained data was mainly done with Horner's method, independently for each well, and assuming generally that the aquifer is homogeneous. Available data from pressure transient tests are limited because of the precision of the tools used, and because pressure buildup was only recorded during eight to twelve hours. The objective was to determine the average transmissivity and the skin factor in order to obtain the productivity of the wells. We gather all available data, including those obtained on the thirteen recent wells, and propose a new interpretation in terms of aquifer model. We use the pressure derivative method developed in the nineties for oil reservoirs which allows a better visualization of the model and of the heterogeneity of the aquifer. Most of the well tests have a derivative pressure curve with a slope equal to zero, that does not change after the well bore effects, confirming that the aquifer is relatively homogenous. However on a dozen of wells, data from pressure transient tests display singular behaviors that can be related to a double porosity or double permeability model for some wells and to a composite model for others. These observations question the validity of a homogeneous model for the Dogger aquifer in the Paris basin and the currently used parameters for the thermal and hydrodynamic predictive model of geothermal exploitation. Finally, this work increases our understanding of the Dogger aquifer in the Paris basin and will allow the optimization of the ongoing hydraulic tests and

  11. An in situ tensile test apparatus for polymers in high pressure hydrogen

    NASA Astrophysics Data System (ADS)

    Alvine, K. J.; Kafentzis, T. A.; Pitman, S. G.; Johnson, K. I.; Skorski, D.; Tucker, J. C.; Roosendaal, T. J.; Dahl, M. E.

    2014-10-01

    Degradation of material properties by high-pressure hydrogen is an important factor in determining the safety and reliability of materials used in high-pressure hydrogen storage and delivery. Hydrogen damage mechanisms have a time dependence that is linked to hydrogen outgassing after exposure to the hydrogen atmosphere that makes ex situ measurements of mechanical properties problematic. Designing in situ measurement instruments for high-pressure hydrogen is challenging due to known hydrogen incompatibility with many metals and standard high-power motor materials such as Nd. Here we detail the design and operation of a solenoid based in situ tensile tester under high-pressure hydrogen environments up to 42 MPa (6000 psi). Modulus data from high-density polyethylene samples tested under high-pressure hydrogen at 35 MPa (5000 psi) are also reported as compared to baseline measurements taken in air.

  12. An In-situ Tensile Test Apparatus for Polymers in High Pressure Hydrogen

    SciTech Connect

    Alvine, Kyle J.; Kafentzis, Tyler A.; Pitman, Stan G.; Johnson, Kenneth I.; Skorski, Daniel C.; Tucker, Joseph C.; Roosendaal, Timothy J.; Dahl, Michael E.

    2014-10-10

    Degradation of material properties by high-pressure hydrogen is an important factor in determining the safety and reliability of materials used in high-pressure hydrogen storage and delivery. Hydrogen damage mechanisms have a time dependence that is linked to hydrogen outgassing after exposure to the hydrogen atmosphere that makes ex-situ measurements of mechanical properties problematic. Designing in-situ measurement instruments for high-pressure hydrogen is challenging due to known hydrogen incompatibility with many metals and standard high-power motor materials like Nd. Here we detail the design and operation of a solenoid based in-situ tensile tester under high-pressure hydrogen environments up to 5,000 psi. Modulus data from high-density polyethylene (HDPE) samples tested under high-pressure hydrogen are also reported as compared to baseline measurements taken in air.

  13. An in situ tensile test apparatus for polymers in high pressure hydrogen

    SciTech Connect

    Alvine, K. J. Kafentzis, T. A.; Pitman, S. G.; Johnson, K. I.; Skorski, D.; Tucker, J. C.; Roosendaal, T. J.; Dahl, M. E.

    2014-10-15

    Degradation of material properties by high-pressure hydrogen is an important factor in determining the safety and reliability of materials used in high-pressure hydrogen storage and delivery. Hydrogen damage mechanisms have a time dependence that is linked to hydrogen outgassing after exposure to the hydrogen atmosphere that makes ex situ measurements of mechanical properties problematic. Designing in situ measurement instruments for high-pressure hydrogen is challenging due to known hydrogen incompatibility with many metals and standard high-power motor materials such as Nd. Here we detail the design and operation of a solenoid based in situ tensile tester under high-pressure hydrogen environments up to 42 MPa (6000 psi). Modulus data from high-density polyethylene samples tested under high-pressure hydrogen at 35 MPa (5000 psi) are also reported as compared to baseline measurements taken in air.

  14. Composite Overwrapped Pressure Vessels (COPV) Stress Rupture Test: Part 2. Part 2

    NASA Technical Reports Server (NTRS)

    Russell, Richard; Flynn, Howard; Forth, Scott; Greene, Nathanael; Kezirian, Michael; Varanauski, Don; Leifeste, Mark; Yoder, Tommy; Woodworth, Warren

    2010-01-01

    One of the major concerns for the aging Space Shuttle fleet is the stress rupture life of composite overwrapped pressure vessels (COPVs). Stress rupture life of a COPY has been defined as the minimum time during which the composite maintains structural integrity considering the combined effects of stress levels and time. To assist in the evaluation of the aging COPVs in the Orbiter fleet an analytical reliability model was developed. The actual data used to construct this model was from testing of COPVs constructed of similar, but not exactly same materials and pressure cycles as used on Orbiter vessels. Since no actual Orbiter COPV stress rupture data exists the Space Shuttle Program decided to run a stress rupture test to compare to model predictions. Due to availability of spares, the testing was unfortunately limited to one 40" vessel. The stress rupture test was performed at maximum operating pressure at an elevated temperature to accelerate aging. The test was performed in two phases. The first phase, 130 F, a moderately accelerated test designed to achieve the midpoint of the model predicted point reliability. A more aggressive second phase, performed at 160 F, was designed to determine if the test article will exceed the 95% confidence interval ofthe model. In phase 3, the vessel pressure was increased to above maximum operating pressure while maintaining the phase 2 temperature. After reaching enough effectives hours to reach the 99.99% confidence level of the model phase 4 testing began when the temperature was increased to greater than 170 F. The vessel was maintained at phase 4 conditions until it failed after over 3 million effect hours. This paper will discuss the results of this test, it's implications and possible follow-on testing.

  15. Design, Analysis and Testing of a PRSEUS Pressure Cube to Investigate Assembly Joints

    NASA Technical Reports Server (NTRS)

    Yovanof, Nicolette; Lovejoy, Andrew E.; Baraja, Jaime; Gould, Kevin

    2012-01-01

    Due to its potential to significantly increase fuel efficiency, the current focus of NASA's Environmentally Responsible Aviation Program is the hybrid wing body (HWB) aircraft. Due to the complex load condition that exists in HWB structure, as compared to traditional aircraft configurations, light-weight, cost-effective and manufacturable structural concepts are required to enable the HWB. The Pultruded Rod Stitched Efficient Unitized Structure (PRSEUS) concept is one such structural concept. A building block approach for technology development of the PRSEUS concept is being conducted. As part of this approach, a PRSEUS pressure cube was developed as a risk reduction test article to examine a new integral cap joint concept. This paper describes the design, analysis and testing of the PRSEUS pressure cube test article. The pressure cube was required to withstand a 2P, 18.4 psi, overpressure load requirement. The pristine pressure cube was tested to 2.2P with no catastrophic failure. After the addition of barely visible impact damage, the cube was pressure loaded to 48 psi where catastrophic failure occurred, meeting the scale-up requirement. Comparison of pretest and posttest analyses with the cube test response agree well, and indicate that current analysis methods can be used to accurately analyze PRSEUS structure for initial failure response.

  16. Liquid Oxygen Liquid Acquisition Device Bubble Point Tests with High Pressure LOX at Elevated Temperatures

    NASA Technical Reports Server (NTRS)

    Jurns, John M.; Hartwig, Jason W.

    2011-01-01

    When transferring propellant in space, it is most efficient to transfer single phase liquid from a propellant tank to an engine. In earth s gravity field or under acceleration, propellant transfer is fairly simple. However, in low gravity, withdrawing single-phase fluid becomes a challenge. A variety of propellant management devices (PMD) are used to ensure single-phase flow. One type of PMD, a liquid acquisition device (LAD) takes advantage of capillary flow and surface tension to acquire liquid. The present work reports on testing with liquid oxygen (LOX) at elevated pressures (and thus temperatures) (maximum pressure 1724 kPa and maximum temperature 122K) as part of NASA s continuing cryogenic LAD development program. These tests evaluate LAD performance for LOX stored in higher pressure vessels that may be used in propellant systems using pressure fed engines. Test data shows a significant drop in LAD bubble point values at higher liquid temperatures, consistent with lower liquid surface tension at those temperatures. Test data also indicates that there are no first order effects of helium solubility in LOX on LAD bubble point prediction. Test results here extend the range of data for LOX fluid conditions, and provide insight into factors affecting predicting LAD bubble point pressures.

  17. Design and Test of a Liquid Oxygen / Liquid Methane Thruster with Cold Helium Pressurization Heat Exchanger

    NASA Technical Reports Server (NTRS)

    Melcher, John C.; Morehead, Robert L.; Atwell, Matthew J.; Hurlbert, Eric A.

    2015-01-01

    A liquid oxygen / liquid methane 2,000 lbf thruster was designed and tested in conjuction with a nozzle heat exchanger for cold helium pressurization. Cold helium pressurization systems offer significant spacecraft vehicle dry mass savings since the pressurant tank size can be reduced as the pressurant density is increased. A heat exchanger can be incorporated into the main engine design to provide expansion of the pressurant supply to the propellant tanks. In order to study the systems integration of a cold-helium pressurization system, a 2,000 lbf thruster with a nozzle heat exchanger was designed for integration into the Project Morpheus vehicle at NASA Johnson Space Center. The testing goals were to demonstrate helium loading and initial conditioning to low temperatures, high-pressure/low temperature storage, expansion through the main engine heat exchanger, and propellant tank injection/pressurization. The helium pressurant tank was an existing 19 inch diameter composite-overwrap tank, and the targert conditions were 4500 psi and -250 F, providing a 2:1 density advantage compared to room tempatrue storage. The thruster design uses like-on-like doublets in the injector pattern largely based on Project Morpheus main engine hertiage data, and the combustion chamber was designed for an ablative chamber. The heat exchanger was installed at the ablative nozzle exit plane. Stand-alone engine testing was conducted at NASA Stennis Space Center, including copper heat-sink chambers and highly-instrumented spoolpieces in order to study engine performance, stability, and wall heat flux. A one-dimensional thermal model of the integrated system was completed. System integration into the Project Morpheus vehicle is complete, and systems demonstrations will follow.

  18. Pressure capillary spot-test for the detection of pollutants in crops, vegetation and environment

    SciTech Connect

    Rathore, H.S.; Gupta, S.; Khan, H.A.

    1986-01-01

    A new, simple, sensitive and selective technique, pressure capillary spot test, has been developed for the detection and determination of pollutants containing amino, carbonyl, carboxylic or phenolic groups. The pressure has been reduced with the help of a suction pump and a capillary containing p-dimethylaminobenzaldehyde has been used as detector for the semi-quantitative determination of plant growth regulators, indoleacetic acids, in wheat shoots.

  19. Test of a novel miniature blood pressure sensor in the coronary arteries of a swine model

    NASA Astrophysics Data System (ADS)

    Wu, Nan; Sun, Kai; Zou, Xiaotian; Barringhaus, Kurt; Wang, Xingwei

    2011-06-01

    Fractional flow reserve (FFR) has proven to be very useful in diagnosis of narrowed coronary arteries. It is a technique that is used in coronary catheterization to measure blood pressure difference across a coronary artery stenosis in maximal flow. In-vivo blood pressure measurement is critical in FFR diagnosis. This paper presents a novel miniature all-optical fiber blood pressure sensor. It is based on Fabry-Perot (FP) interferometry principle. The FP cavity was fabricated by directly wet etching the fiber tip. Then, a diaphragm with well-controlled thickness was bonded to the end face of the fiber using the thermal bonding technique. Finally, the sensor was packaged with a bio-compatible and flexible coil for animal tests. A 25-50 kg Yorkshire swine model was introduced as the animal test target. The left anterior descending coronary artery (LAD) was exposed, and beyond the takeoff of the largest diagonal branch, a 3.0 mm vascular occluder was secured. Firstly, standard invasive manometry was used to obtain the blood pressure as baseline. Next, a guiding catheter was introduced into the ostium of the left main coronary artery, and the miniature blood pressure sensor was advanced into the LAD at a point beyond the vascular occlude. The blood pressure beyond the vascular occlude was recorded. The sensor successfully recorded the blood pressure at both near-end and far-end of the vascular occluder.

  20. High pressure hypervelocity electrothermal wind tunnel performance study and subscale tests

    NASA Technical Reports Server (NTRS)

    Rizkalla, Oussama F.; Chinitz, Wallace; Witherspoon, F. D.; Burton, Rodney L.

    1992-01-01

    The feasibility of a Mach 10 to 20, high pressure electrothermal wind tunnel was assessed. A heater based on a continuous high power electric arc discharge capable of heating air to temperatures above 10,000 K and pressures of 15,000 atm is the key element of this wind tunnel. Results of analytical study indicate that the facility is capable of simulation conditions suitable for hypervelocity airbreathing propulsion testing up to Mach 16. In this case simulation was limited by pressure containment, high nozzle throat heat flux rates, and chemical freezing in the nozzle. The high total pressure capability improved the recombination chemistry in the facility nozzle as chemical equilibrium prevailed to the freezing point. Steady arc discharges were observed with liquid nitrogen flowing into the arc chamber during tests based on the two millisecond test facility. The measured steady pressure in the arc chamber was 4559 psi, which is two times greater than maximum total pressure obtainable in conventional arc heaters.

  1. Suitport Feasibility - Development and Test of a Suitport and Space Suit for Human Pressurized Space Suit Donning Tests

    NASA Technical Reports Server (NTRS)

    Boyle, Robert M.; Mitchell, Kathryn; Allton, Charles; Ju, Hsing

    2011-01-01

    The suitport concept has been recently implemented as part of the small pressurized lunar rover (Currently the Space Exploration vehicle, or SEV) and the Multi-Mission Space Exploration Vehicle (MMSEV) concept demonstrator vehicle. Suitport replaces or augments the traditional airlock function of a spacecraft by providing a bulkhead opening, capture mechanism, and sealing system to allow ingress and egress of a spacesuit while the spacesuit remains outside of the pressurized volume of the spacecraft. This presents significant new opportunities to EVA exploration in both microgravity and surface environments. The suitport concept will enable three main improvements in EVA by providing reductions in: pre-EVA time from hours to less than thirty minutes; airlock consumables; contamination returned to the cabin with the EVA crewmember. To date, the first generation suitport has been tested with mockup suits on the rover cabins and pressurized on a bench top engineering unit. The work on the rover cabin has helped define the operational concepts and timelines, and has demonstrated the potential of suitport to save significant amounts of crew time before and after EVAs. The work with the engineering unit has successfully demonstrated the pressurizable seal concept including the ability to seal after the introduction and removal of contamination to the sealing surfaces. Using this experience, a second generation suitport was designed. This second generation suitport has been tested with a spacesuit prototype using the pressure differentials of the spacecraft. This test will be performed using the JSC B32 Chamber B, a human rated vacuum chamber. This test will include human rated suitports, the suitport compatible prototype suit, and chamber modifications. This test will bring these three elements together in the first ever pressurized donning of a rear entry suit through a suitport. This paper presents design of a human rated second generation suitport, modifications to

  2. The low-cost and precise piston gas pressure regulator

    NASA Astrophysics Data System (ADS)

    Kudasik, Mateusz; Skoczylas, Norbert

    2016-03-01

    The present paper discusses the concept and functioning of an innovative instrument for precise stabilization of gas pressure. The piston gas pressure regulator was constructed at the Strata Mechanics Research Institute of the Polish Academy of Sciences. The tests to which the instrument was subjected involved observing the values of stabilized pressure at the level of 10 bar and 3 bar, for various gas flow rates at the outlet of the instrument. The piston gas pressure regulator operates within the range of 0-10 bar and the gas flow range of 0-240 cm3 min-1. The precision of the process of stabilizing the initial pressure is  ±0.005 bar, regardless of the gas pressure value and the flow rate observed at the outlet of the instrument. Although the pressure transducer’s accuracy is 0.25% of the full range, the conducted tests of the regulator demonstrated that the obtained changeability of the stabilized pressure is at least two times lower. Unlike some other gas pressure regulators available on the market, the instrument constructed by the authors of the present paper is highly precise when it comes to the process of stabilization, and inexpensive to build.

  3. Pressure Distribution Tests on a Series of Clark Y Biplane Cellules with Special Reference to Stability

    NASA Technical Reports Server (NTRS)

    Noyes, Richard W

    1933-01-01

    The pressure distribution data discussed in this report represents the results of part of an investigation conducted on the factors affecting the aerodynamic safety of airplanes. The present tests were made on semispan, circular-tipped Clark Y airfoil models mounted in the conventional manner on a separation plane. Pressure readings were made simultaneously at all test orifices at each of 20 angles of attack between -8 degrees and +90 degrees. The results of the tests on each wing arrangement are compared on the bases of maximum normal force coefficient, lateral stability at a low rate of roll, and relative longitudinal stability. Tabular data are also presented giving the center of pressure location of each wing.

  4. A simulator for oscillometric blood-pressure signals to test automated noninvasive sphygmomanometers

    NASA Astrophysics Data System (ADS)

    Riedel, W.; Mieke, S.; Seemann, R.; Ittermann, B.

    2011-02-01

    A device was developed allowing to generate simulated human blood pressure signals for the purpose of testing the performance of automated noninvasive sphygmomanometers. The apparatus reproducibly generates blood-pressure oscillations synthesized from prerecorded measurements on human subjects. These real-life data allow for a much better evaluation of the accuracy of blood-pressure measurements than the existing simulators using artificial and thus less realistic waveforms. To assess the performance of a given sphygmomanometer under both stable and varying conditions, generated signals can be repeated in their original shape or distorted by well-defined artifacts. In comparison to clinical tests, the procedural influences on the performance testing of sphygmomanometers are largely reduced when the simulator is used.

  5. Comparison of the Effects of using Tygon Tubing in Rocket Propulsion Ground Test Pressure Transducer Measurements

    NASA Technical Reports Server (NTRS)

    Farr, Rebecca A.; Wiley, John T.; Vitarius, Patrick

    2005-01-01

    This paper documents acoustics environments data collected during liquid oxygen- ethanol hot-fire rocket testing at NASA Marshall Space Flight Center in November- December 2003. The test program was conducted during development testing of the RS-88 development engine thrust chamber assembly in support of the Orbital Space Plane Crew Escape System Propulsion Program Pad Abort Demonstrator. In addition to induced environments analysis support, coincident data collected using other sensors and methods has allowed benchmarking of specific acoustics test measurement methodologies during propulsion tests. Qualitative effects on data characteristics caused by using tygon sense lines of various lengths in pressure transducer measurements is discussed here.

  6. Test results on direct containment heating by high-pressure melt ejection into the Surtsey vessel: The TDS test series

    SciTech Connect

    Allen, M.D.; Blanchat, T.K.; Pilch, M.M.

    1994-08-01

    The Technology Development and Scoping (TDS) test series was conducted to test and develop instrumentation and procedures for performing steam-driven, high-pressure melt ejection (HPME) experiments at the Surtsey Test Facility to investigate direct containment heating (DCH). Seven experiments, designated TDS-1 through TDS-7, were performed in this test series. These experiments were conducted using similar initial conditions; the primary variable was the initial pressure in the Surtsey vessel. All experiments in this test series were performed with a steam driving gas pressure of {approx_equal} 4 MPa, 80 kg of lumina/iron/chromium thermite melt simulant, an initial hole diameter of 4.8 cm (which ablated to a final hole diameter of {approx_equal} 6 cm), and a 1/10th linear scale model of the Surry reactor cavity. The Surtsey vessel was purged with argon (<0.25 mol% O{sub 2}) to limit the recombination of hydrogen and oxygen, and gas grab samples were taken to measure the amount of hydrogen produced.

  7. Mass modeling for bars

    NASA Technical Reports Server (NTRS)

    Butler, Thomas G.

    1987-01-01

    Methods of modeling mass for bars are surveyed. A method for extending John Archer's concept of consistent mass beyond just translational inertia effects is included. Recommendations are given for various types of modeling situations.

  8. A theoretical and flight test study of pressure fluctuations under a turbulent boundary layer. Part 2: Flight test study

    NASA Technical Reports Server (NTRS)

    Panton, R. L.; Lowery, R. L.; Reischman, M. M.

    1967-01-01

    The study of pressure fluctuations under a turbulent boundary layer was undertaken with the objective of extending previous work to lower frequencies. Wind tunnel and flight test measurements are invalid at low frequencies because of extraneous acoustic noises and free stream turbulence. A glider was instrumented and used as a test bed to carry microphones into a smooth flow free of acoustic noise. Hodgson had previously measured the spectrum of boundary layer noise on a glider wing. These tests showed a drop off at low frequencies that could not be reproduced in any other facility. The measurements were made on the forward fuselage of a glider where the boundary layer could develop naturally and have some length in a zero pressure gradient before the measurements were made. Two different sets of measurements were made.

  9. The interplay of parental support, parental pressure and test anxiety--Gender differences in adolescents.

    PubMed

    Ringeisen, Tobias; Raufelder, Diana

    2015-12-01

    This study examined gender-specific relationships between adolescents' perceptions of school-related support/pressure from their parents and test anxiety. A sample of German students (N = 845; Mage = 15.32; SD = .49) completed questionnaires that measured their perceived parental support/pressure (for mother and father separately) as well as the four main components of test anxiety (worry, interference, lack of confidence, and emotionality). Gender-specific relations were identified using multigroup structural equation modeling: For girls, perceived maternal pressure was positively associated with emotionality and interference; for boys, perceived father pressure and father support were positively associated with interference and worry, respectively. For both genders, perceived mother pressure and support were related to lack of confidence. Our findings suggest that adolescents' perceptions of maternal attitudes are associated with students' self-confidence irrespective of the child's gender, whereas the remaining facets of test anxiety follow same-sex trajectories between perceived parental attitudes and adolescents' test anxiety. PMID:26378971

  10. Laboratory and workplace assessments of rivet bucking bar vibration emissions.

    PubMed

    McDowell, Thomas W; Warren, Christopher; Xu, Xueyan S; Welcome, Daniel E; Dong, Ren G

    2015-04-01

    Sheet metal workers operating rivet bucking bars are at risk of developing hand and wrist musculoskeletal disorders associated with exposures to hand-transmitted vibrations and forceful exertions required to operate these hand tools. New bucking bar technologies have been introduced in efforts to reduce workplace vibration exposures to these workers. However, the efficacy of these new bucking bar designs has not been well documented. While there are standardized laboratory-based methodologies for assessing the vibration emissions of many types of powered hand tools, no such standard exists for rivet bucking bars. Therefore, this study included the development of a laboratory-based method for assessing bucking bar vibrations which utilizes a simulated riveting task. With this method, this study evaluated three traditional steel bucking bars, three similarly shaped tungsten alloy bars, and three bars featuring spring-dampeners. For comparison the bucking bar vibrations were also assessed during three typical riveting tasks at a large aircraft maintenance facility. The bucking bars were rank-ordered in terms of unweighted and frequency-weighted acceleration measured at the hand-tool interface. The results suggest that the developed laboratory method is a reasonable technique for ranking bucking bar vibration emissions; the lab-based riveting simulations produced similar rankings to the workplace rankings. However, the laboratory-based acceleration averages were considerably lower than the workplace measurements. These observations suggest that the laboratory test results are acceptable for comparing and screening bucking bars, but the laboratory measurements should not be directly used for assessing the risk of workplace bucking bar vibration exposures. The newer bucking bar technologies exhibited significantly reduced vibrations compared to the traditional steel bars. The results of this study, together with other information such as rivet quality, productivity, tool

  11. Laboratory and Workplace Assessments of Rivet Bucking Bar Vibration Emissions

    PubMed Central

    McDowell, Thomas W.; Warren, Christopher; Xu, Xueyan S.; Welcome, Daniel E.; Dong, Ren G.

    2016-01-01

    Sheet metal workers operating rivet bucking bars are at risk of developing hand and wrist musculoskeletal disorders associated with exposures to hand-transmitted vibrations and forceful exertions required to operate these hand tools. New bucking bar technologies have been introduced in efforts to reduce workplace vibration exposures to these workers. However, the efficacy of these new bucking bar designs has not been well documented. While there are standardized laboratory-based methodologies for assessing the vibration emissions of many types of powered hand tools, no such standard exists for rivet bucking bars. Therefore, this study included the development of a laboratory-based method for assessing bucking bar vibrations which utilizes a simulated riveting task. With this method, this study evaluated three traditional steel bucking bars, three similarly shaped tungsten alloy bars, and three bars featuring spring-dampeners. For comparison the bucking bar vibrations were also assessed during three typical riveting tasks at a large aircraft maintenance facility. The bucking bars were rank-ordered in terms of unweighted and frequency-weighted acceleration measured at the hand-tool interface. The results suggest that the developed laboratory method is a reasonable technique for ranking bucking bar vibration emissions; the lab-based riveting simulations produced similar rankings to the workplace rankings. However, the laboratory-based acceleration averages were considerably lower than the workplace measurements. These observations suggest that the laboratory test results are acceptable for comparing and screening bucking bars, but the laboratory measurements should not be directly used for assessing the risk of workplace bucking bar vibration exposures. The newer bucking bar technologies exhibited significantly reduced vibrations compared to the traditional steel bars. The results of this study, together with other information such as rivet quality, productivity, tool

  12. 30 CFR 250.523 - How long do I keep records of casing pressure and diagnostic tests?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... and diagnostic tests? 250.523 Section 250.523 Mineral Resources MINERALS MANAGEMENT SERVICE... casing pressure and diagnostic tests? Records of casing pressure and diagnostic tests must be kept at the field office nearest the well for a minimum of 2 years. The last casing diagnostic test for each...

  13. 30 CFR 250.523 - How long do I keep records of casing pressure and diagnostic tests?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... and diagnostic tests? 250.523 Section 250.523 Mineral Resources BUREAU OF SAFETY AND ENVIRONMENTAL... records of casing pressure and diagnostic tests? Records of casing pressure and diagnostic tests must be kept at the field office nearest the well for a minimum of 2 years. The last casing diagnostic test...

  14. 30 CFR 250.524 - How long do I keep records of casing pressure and diagnostic tests?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... and diagnostic tests? 250.524 Section 250.524 Mineral Resources BUREAU OF SAFETY AND ENVIRONMENTAL... records of casing pressure and diagnostic tests? Records of casing pressure and diagnostic tests must be kept at the field office nearest the well for a minimum of 2 years. The last casing diagnostic test...

  15. 30 CFR 250.524 - How long do I keep records of casing pressure and diagnostic tests?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... and diagnostic tests? 250.524 Section 250.524 Mineral Resources BUREAU OF SAFETY AND ENVIRONMENTAL... records of casing pressure and diagnostic tests? Records of casing pressure and diagnostic tests must be kept at the field office nearest the well for a minimum of 2 years. The last casing diagnostic test...

  16. Recommended Practice for Pressure Measurements and Calculation of Effective Pumping Speeds During Electric Propulsion Testing

    NASA Technical Reports Server (NTRS)

    Dankanich, John W.; Walker, Mitchell; Swiatek, Michael W.; Yim, John T.

    2013-01-01

    The electric propulsion community has been implored to establish and implement a set of universally applicable test standards during the research, development, and qualification of electric propulsion systems. Variability between facility-to-facility and more importantly ground-to-flight performance can result in large margins in application or aversion to mission infusion. Performance measurements and life testing under appropriate conditions can be costly and lengthy. Measurement practices must be consistent, accurate, and repeatable. Additionally, the measurements must be universally transportable across facilities throughout the development, qualification, spacecraft integration, and on-orbit performance. A recommended practice for making pressure measurements, pressure diagnostics, and calculating effective pumping speeds with justification is presented.

  17. G-Tunnel pressurized slot-testing preparations; Yucca Mountain Site Characterization Project

    SciTech Connect

    Zimmerman, R.M.; Sifre-Soto, C.; Mann, K.L.; Bellman, R.A. Jr.; Luker, S.; Dodds, D.J.

    1992-04-01

    Designers and analysts of radioactive waste repositories must be able to predict the mechanical behavior of the host rock. Sandia National laboratories elected to conduct a development program on pressurized slot testing and featured (1) development of an improved method to cut slots using a chain saw with diamond-tipped cutters, (2) measurements useful for determining in situ stresses normal to slots, (3) measurements applicable for determining the in situ modulus of deformation parallel to a drift surface, and (4) evaluations of the potentials of pressurized slot strength testing. This report describes the preparations leading to the measurements and evaluations.

  18. Combination Of Thermography And Pressure Tests To Combat Air Leakage Problems In Building Enclosures

    NASA Astrophysics Data System (ADS)

    Spruin, W. G.

    1987-05-01

    Uncontrolled air leakage in a building enclosure is the main component of space heating and cooling costs. In Atlantic Canada, Public Works Canada has combined thermography and pressure testing to identify design and construction problems in new construction and to identify specific areas of air leakage in existing housing stock. A study case shows how thermography and pressure testing has been utilized to locate and compare specific areas of air leakage in a residence before and after air sealing. The study provides both quantitative and qualitative evidence of how air sealing increases the air tightness in building enclosures.

  19. ALIP with conducting bars in the channel

    NASA Astrophysics Data System (ADS)

    Krishbergs, R.

    2009-03-01

    Electromagnetic processes in the channel of a cylindrical induction pump having longitudinal copper bars of large electric conductivity have been analyzed. The possibility to increase the pressure developed by the pump if compared to the usual pump (ALIP) is considered as well as the increase of the coefficient of pressure head weakening k_{0 c} more than unity and its effects on the efficiency coefficient. Figs 5, Refs 5.

  20. Stress Rupture Testing and Analysis of the NASA WSTF-JPL Carbon Overwrapped Pressure Vessels

    NASA Technical Reports Server (NTRS)

    Greene, Nathanael; Yoder, Tommy; Saulsberry, Regor; Grimes, Lorie; Thesken, John; Phoenix, Leigh

    2007-01-01

    Carbon composite overwrapped pressure vessels (COPVs) are widely used in applications from spacecraft to life support. COPV technology provides a pressurized media storage advantage over amorphous technology with weight savings on the order of 30 percent. The National Aeronautics and Space Administration (NASA) has been supporting the development of this technology since the early 1970's with an interest in safe application of these components to reduce mass to orbit. NASA White Sands Test Facility (WSTF) has been testing components in support of this objective since the 1980s and has been involved in test development and analysis to address affects of impact, propellant and cryogenic fluids exposure on Kevlar and carbon epoxy. The focus of this paper is to present results of a recent joint WSTF-Jet Propulsion Laboratories (JPL) effort to assess safe life of these components. The WSTF-JPL test articles consisted of an aluminum liner and a carbon fiber overwrap in an industry standard epoxy resin system. The vessels were specifically designed with one plus-minus helical wrap and one hoop wrap over the helical and they measured 4.23 x 11.4 in. long. 120 test articles were manufactured in August of 1998 of one lot fiber and resin and the 110 test articles were delivered to WSTF for test. Ten of the 120 test articles were burst tested at the manufacturer to establish the delivered fiber stress. Figure 1 shows a test article in a pre burst condition and with a hoop fiber failure (no leak of pressurized media) and post burst (failure of liner and loss of pressurized media).

  1. Water Flow Testing and Unsteady Pressure Analysis of a Two-Bladed Liquid Oxidizer Pump Inducer

    NASA Technical Reports Server (NTRS)

    Schwarz, Jordan B.; Mulder, Andrew; Zoladz, Thomas

    2011-01-01

    The unsteady fluid dynamic performance of a cavitating two-bladed oxidizer turbopump inducer was characterized through sub-scale water flow testing. While testing a novel inlet duct design that included a cavitation suppression groove, unusual high-frequency pressure oscillations were observed. With potential implications for inducer blade loads, these high-frequency components were analyzed extensively in order to understand their origins and impacts to blade loading. Water flow testing provides a technique to determine pump performance without the costs and hazards associated with handling cryogenic propellants. Water has a similar density and Reynolds number to liquid oxygen. In a 70%-scale water flow test, the inducer-only pump performance was evaluated. Over a range of flow rates, the pump inlet pressure was gradually reduced, causing the flow to cavitate near the pump inducer. A nominal, smooth inducer inlet was tested, followed by an inlet duct with a circumferential groove designed to suppress cavitation. A subsequent 52%-scale water flow test in another facility evaluated the combined inducer-impeller pump performance. With the nominal inlet design, the inducer showed traditional cavitation and surge characteristics. Significant bearing loads were created by large side loads on the inducer during synchronous cavitation. The grooved inlet successfully mitigated these loads by greatly reducing synchronous cavitation, however high-frequency pressure oscillations were observed over a range of frequencies. Analytical signal processing techniques showed these oscillations to be created by a rotating, multi-celled train of pressure pulses, and subsequent CFD analysis suggested that such pulses could be created by the interaction of rotating inducer blades with fluid trapped in a cavitation suppression groove. Despite their relatively low amplitude, these high-frequency pressure oscillations posed a design concern due to their sensitivity to flow conditions and

  2. Interrelationship of Nondestructive Evaluation Methodologies Applied to Testing of Composite Overwrapped Pressure Vessels

    NASA Technical Reports Server (NTRS)

    Leifeste, Mark R.

    2007-01-01

    Composite Overwrapped Pressure Vessels (COPVs) are commonly used in spacecraft for containment of pressurized gases and fluids, incorporating strength and weight savings. The energy stored is capable of extensive spacecraft damage and personal injury in the event of sudden failure. These apparently simple structures, composed of a metallic media impermeable liner and fiber/resin composite overwrap are really complex structures with numerous material and structural phenomena interacting during pressurized use which requires multiple, interrelated monitoring methodologies to monitor and understand subtle changes critical to safe use. Testing of COPVs at NASA Johnson Space Center White Sands T est Facility (WSTF) has employed multiple in-situ, real-time nondestructive evaluation (NDE) methodologies as well as pre- and post-test comparative techniques to monitor changes in material and structural parameters during advanced pressurized testing. The use of NDE methodologies and their relationship to monitoring changes is discussed based on testing of real-world spacecraft COPVs. Lessons learned are used to present recommendations for use in testing, as well as a discussion of potential applications to vessel health monitoring in future applications.

  3. Ten year environmental test of glass fiber/epoxy pressure vessels

    NASA Technical Reports Server (NTRS)

    Faddoul, J. R.

    1985-01-01

    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.

  4. Pressure drop testing of corrugated stainless steel pliable gas tubing (PLT)

    NASA Astrophysics Data System (ADS)

    Srinivasan, Bharadwaj

    An experimental program was initiated to determine the Darcy friction factor in straight corrugated stainless steel pliable gas tubing (PLT). Pressure loss tests were conducted on PLT per I.S. EN 15266:2007. A power law least-squares curve fit was used to relate pressure loss per unit length as a function of volume flow rate. The calculated coefficient of determination values for the straight PLT exceeded 0.90 indicating suitable correlation. Darcy friction factors were calculated from test data for each case and plotted on a Moody diagram as a function of Reynolds number based on the minimum PLT cross section. For Reynolds numbers less than 2300 the pressure loss data for PLT yielded an inverse relationship between the Darcy friction factor and the Reynolds number, with a proportionality coefficient of 49. The measurement uncertainty estimates for straight sections was performed with a 95% confidence level. Straight PLT flow rates for air and representative fuel gases that would yield a pressure loss Deltap = 1 mbar were calculated as a function of PLT length and diameter. Fitting pressure loss tests were performed for elbows, tees, and bullhead tees. The loss coefficients were evaluated and tabulated. The calculated coefficient of determination values for the fittings was found to be low. The measurement uncertainty was calculated using the root sum square error method and was found to be very high because of the low flow rates considered in this experiment.

  5. The Orion Atmosphere Revitalization Technology in Manned Ambient Pressure Space Suit Testing

    NASA Technical Reports Server (NTRS)

    Button, Amy; Sweterlitsch, Jeffrey

    2011-01-01

    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 Atmosphere Revitalization System (ARS) for moderate duration missions of the Orion Multipurpose Crew Vehicle. The Orion ARS is designed to support not only open-cabin operations, tests of which have been reported in previous years at this conference, but also closed space suit-loop operations. A previous low-pressure suit loop test was performed with a human metabolic simulator, and humans wearing emergency masks were tested in a closed-loop configuration before that. In late 2011, simple tests were performed in a suit-loop configuration with human test subjects in prototype space suits with prototype umbilicals at ambient and two slightly above-ambient pressures. Trace contaminant filters and a prototype blower were also incorporated into the test rig. This paper discusses the performance of the ARS technology in that 2011 test configuration.

  6. Flight test evaluation of an RAF high altitude partial pressure protective assembly

    NASA Technical Reports Server (NTRS)

    Ashworth, G. R.; Putnam, T. W.; Dana, W. J.; Enevoldson, E. K.; Winter, W. R.

    1979-01-01

    A partial pressure suit was evaluated during tests in an F-104 and F-15 as a protective garment for emergency descents. The garment is an pressure jerkin and modified anti-g suit combined with an oronasal mask. The garment can be donned and doffed at the aircraft to minimize thermal buildup. The oronasal mask was favored by the pilots due to its immobility on the face during high g-loading. The garment was chosen to provide optimum dexterity for the pilot, which is not available in a full pressure suit, while protecting the pilot at altitudes up to 18,288 meters, during a cabin decompression, and subsequent aircraft descent. During cabin decompressions in the F-104 and F-15, cabin pressure altitude was measured at various aircraft angles of attack, Mach numbers, and altitudes to determine the effect of the aerodynamic slipstream on the cabin altitude.

  7. Oscillatory pressure transients after flow interruption during bronchial challenge test in children.

    PubMed

    Frey, U; Kraemer, R

    1997-01-01

    The measurement of the conventional interrupter resistance (Rint) is dependent on pressure equilibration between alveolar and airway opening pressure, which is often not achieved in the presence of severe airways obstruction or in small children. The damping properties (d) of postocclusional oscillatory pressure transients after rapid flow interrruption can be assessed independent of complete pressure equilibration, and we have previously shown them to be correlated to resistive properties of the respiratory system. We wanted to determine whether these transients were an expression of acoustic properties of the air in the airways, or whether they were caused by an interaction of gas and lung tissue, and whether d was more sensitive than Rint to changes in airway mechanics. Bronchial challenge tests were carried out with cumulative doses of inhaled carbachol in 10 healthy children (aged 7-14 yrs) and 50 asthmatic children (aged 5-15 yrs). The airflow interruptions were performed with a combined nebulizer-shutter head, allowing resistance measurements with each breath. The frequency, and the damping factor of the postocclusional pressure transients changed significantly during carbachol challenge in both groups of children. The provocation dose (PD) at which the damping factor (d) of the oscillatory pressure transients increased more than 2 SD above the baseline mean ("variance-based", PDvb) was lower than the PDvb of the end-interruption resistance (Rint, EI). These changes in frequency and damping factor were reversible after inhaling salbutamol. These findings suggest that the damping properties of the postocclusional pressure transients after flow interruption can be used as a sensitive parameter to assess changes in airway mechanics during bronchial challenge test in children in whom pressure equilibration is frequently not achieved during airflow interruption due to airways obstruction. PMID:9032496

  8. Tri-Gas Pressurization System Testing and Modeling for Cryogenic Applications

    NASA Technical Reports Server (NTRS)

    Taylor, B.; Polsgrove, R.; Stephens, J.; Hedayat, A.

    2014-01-01

    The use of Tri-gas in rocket propulsion systems is somewhat of a new technology. This paper defines Tri-gas as a mixture of gases composed largely of helium with a small percentage of a stoichiometric mixture of hydrogen and oxygen. When exposed to a catalyst the hydrogen and oxygen in the mixture combusts, significantly raising the temperature of the mixture. The increase in enthalpy resulting from the combustion process significantly decreases the required quantity of gas needed to pressurize the ullage of the vehicle propellant tanks. The objective of this effort was to better understand the operating characteristics of Tri-gas in a pressurization system with low temperature applications. In conjunction with ongoing programs at NASA Marshall Space Flight Center, an effort has been undertaken to evaluate the operating characteristics of Tri-gas through modeling and bench testing. Through improved understanding of the operating characteristics, the risk of using this new technology in a launch vehicle propulsion system was reduced. Bench testing of Tri-gas was a multistep process that targeted gas characteristics and performance aspects that pose a risk to application in a pressurization system. Pressurization systems are vital to propulsion system performance. Keeping a target ullage pressure in propulsions tanks is necessary to supply propellant at the conditions and flow rates required to maintain desired engine functionality. The first component of testing consisted of sampling Tri-gas sources that had been stagnant for various lengths of time in order to determine the rate at which stratification takes place. Second, a bench test was set up in which Tri-gas was sent through a catalyst bed. This test was designed to evaluate the performance characteristics of Tri-gas, under low temperature inlet temperatures, in a flight-like catalyst bed reactor. The third, most complex, test examined the performance characteristics of Tri-gas at low temperature temperatures

  9. Ares I Scale Model Acoustic Test Instrumentation for Acoustic and Pressure Measurements

    NASA Technical Reports Server (NTRS)

    Vargas, Magda B.; Counter, Douglas

    2011-01-01

    Ares I Scale Model Acoustic Test (ASMAT) is a 5% scale model test of the Ares I vehicle, launch pad and support structures conducted at MSFC to verify acoustic and ignition environments and evaluate water suppression systems Test design considerations 5% measurements must be scaled to full scale requiring high frequency measurements Users had different frequencies of interest Acoustics: 200 - 2,000 Hz full scale equals 4,000 - 40,000 Hz model scale Ignition Transient: 0 - 100 Hz full scale equals 0 - 2,000 Hz model scale Environment exposure Weather exposure: heat, humidity, thunderstorms, rain, cold and snow Test environments: Plume impingement heat and pressure, and water deluge impingement Several types of sensors were used to measure the environments Different instrument mounts were used according to the location and exposure to the environment This presentation addresses the observed effects of the selected sensors and mount design on the acoustic and pressure measurements

  10. An evaluation of the pressure proof test concept for 2024-T3 aluminium alloy sheet

    NASA Technical Reports Server (NTRS)

    Dawicke, D. S.; Poe, C. C., Jr.; Newman, J. C.; Harris, C. E.

    1991-01-01

    The concept of pressure proof testing of fuselage structures with fatigue cracks to insure structural integrity was evaluated from a fracture mechanics viewpoint. A generic analytical and experimental investigation was conducted on uniaxially loaded flat panels with crack configurations and stress levels typical of longitudinal lap splice joints in commercial transport aircraft fuselages. The results revealed that the remaining fatigue life after a proof cycle was longer than that without the proof cycle because of crack growth retardation due to increased crack closure. However, based on a crack length that is slightly less than the critical value at the maximum proof stress, the minimum assured life or proof test interval must be no more than 550 pressure cycles for a 1.33 proof factor and 1530 pressure cycles for a 1.5 proof factor to prevent in-flight failures.

  11. NASA GRC's High Pressure Burner Rig Facility and Materials Test Capabilities

    NASA Technical Reports Server (NTRS)

    Robinson, R. Craig

    1999-01-01

    The High Pressure Burner Rig (HPBR) at NASA Glenn Research Center is a high-velocity. pressurized combustion test rig used for high-temperature environmental durability studies of advanced materials and components. The facility burns jet fuel and air in controlled ratios, simulating combustion gas chemistries and temperatures that are realistic to those in gas turbine engines. In addition, the test section is capable of simulating the pressures and gas velocities representative of today's aircraft. The HPBR provides a relatively inexpensive. yet sophisticated means for researchers to study the high-temperature oxidation of advanced materials. The facility has the unique capability of operating under both fuel-lean and fuel-rich gas mixtures. using a fume incinerator to eliminate any harmful byproduct emissions (CO, H2S) of rich-burn operation. Test samples are easily accessible for ongoing inspection and documentation of weight change, thickness, cracking, and other metrics. Temperature measurement is available in the form of both thermocouples and optical pyrometery. and the facility is equipped with quartz windows for observation and video taping. Operating conditions include: (1) 1.0 kg/sec (2.0 lbm/sec) combustion and secondary cooling airflow capability: (2) Equivalence ratios of 0.5- 1.0 (lean) to 1.5-2.0 (rich), with typically 10% H2O vapor pressure: (3) Gas temperatures ranging 700-1650 C (1300-3000 F): (4) Test pressures ranging 4-12 atmospheres: (5) Gas flow velocities ranging 10-30 m/s (50-100) ft/sec.: and (6) Cyclic and steady-state exposure capabilities. The facility has historically been used to test coupon-size materials. including metals and ceramics. However complex-shaped components have also been tested including cylinders, airfoils, and film-cooled end walls. The facility has also been used to develop thin-film temperature measurement sensors.

  12. High-R Walls for New Construction Structural Performance: Wind Pressure Testing

    SciTech Connect

    DeRenzis, A.; Kochkin, V.

    2013-01-01

    This technical report is focused primarily on laboratory testing that evaluates wind pressure performance characteristics for wall systems constructed with exterior insulating sheathing. This research and test activity will help to facilitate the ongoing use of non-structural sheathing options and provide a more in-depth understanding of how wall system layers perform in response to high wind perturbations normal to the surface.

  13. High-R Walls for New Construction Structural Performance. Wind Pressure Testing

    SciTech Connect

    DeRenzis, A.; Kochkin, V.

    2013-01-01

    This technical report is focused primarily on laboratory testing that evaluates wind pressure performance characteristics for wall systems constructed with exterior insulating sheathing. This research and test activity will help to facilitate the ongoing use of non-structural sheathing options and provide a more in-depth understanding of how wall system layers perform in response to high wind perturbations normal to the surface.

  14. FINAL REPORT FOR LOW PRESSURE TESTS OF THE CPU-400 PILOT PLANT

    EPA Science Inventory

    This report presents the progress made during the component design phase of a program to develop an economical and environmentally safe waste-energy system known as the CPU-400. It discusses the hardware development and low pressure testing performed to evaluate CPU-400 operation...

  15. 30 CFR 250.427 - What are the requirements for pressure integrity tests?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 2 2012-07-01 2012-07-01 false What are the requirements for pressure integrity tests? 250.427 Section 250.427 Mineral Resources BUREAU OF SAFETY AND ENVIRONMENTAL ENFORCEMENT, DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Oil and Gas Drilling Operations Casing...

  16. 30 CFR 250.423 - What are the requirements for pressure testing casing?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 2 2010-07-01 2010-07-01 false What are the requirements for pressure testing casing? 250.423 Section 250.423 Mineral Resources MINERALS MANAGEMENT SERVICE, DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Oil and Gas Drilling...

  17. 30 CFR 250.425 - What are the requirements for pressure testing liners?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 2 2010-07-01 2010-07-01 false What are the requirements for pressure testing liners? 250.425 Section 250.425 Mineral Resources MINERALS MANAGEMENT SERVICE, DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Oil and Gas Drilling...

  18. 30 CFR 250.426 - What are the recordkeeping requirements for casing and liner pressure tests?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 2 2010-07-01 2010-07-01 false What are the recordkeeping requirements for casing and liner pressure tests? 250.426 Section 250.426 Mineral Resources MINERALS MANAGEMENT SERVICE, DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Oil...

  19. 30 CFR 250.423 - What are the requirements for pressure testing casing?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... liner in the subsea wellhead or liner hanger. (1) You must ensure that the latching mechanisms or lock down mechanisms are engaged upon installation of each casing string or liner. (2) You must perform a pressure test on the casing seal assembly to ensure proper installation of casing or liner. You...

  20. 30 CFR 250.423 - What are the requirements for pressure testing casing?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... installation of casing or liner in the subsea wellhead or liner hanger. (1) You must ensure that the latching mechanisms or lock down mechanisms are engaged upon installation of each casing string or liner. (2) You must perform a pressure test on the casing seal assembly to ensure proper installation of casing or liner....