Science.gov

Sample records for air inlet piping

  1. 28. Main water inlet and outlet pipes under central corridor ...

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

    28. Main water inlet and outlet pipes under central corridor of filtration bed building. - Lake Whitney Water Filtration Plant, Filtration Plant, South side of Armory Street between Edgehill Road & Whitney Avenue, Hamden, New Haven County, CT

  2. 46 CFR 45.133 - Air pipes.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 2 2010-10-01 2010-10-01 false Air pipes. 45.133 Section 45.133 Shipping COAST GUARD....133 Air pipes. (a) Where an air pipe to any tank extends above the freeboard or superstructure deck— (1) The exposed part of the air pipe must be made of steel and of sufficient thickness to...

  3. 46 CFR 45.133 - Air pipes.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 2 2011-10-01 2011-10-01 false Air pipes. 45.133 Section 45.133 Shipping COAST GUARD....133 Air pipes. (a) Where an air pipe to any tank extends above the freeboard or superstructure deck— (1) The exposed part of the air pipe must be made of steel and of sufficient thickness to...

  4. Biofouling of inlet pipes affects water quality in running seawater aquaria and compromises sponge cell proliferation

    PubMed Central

    Mueller, Benjamin; Vermeij, Mark J.A.; van der Geest, Harm H.G.

    2015-01-01

    Marine organism are often kept, cultured, and experimented on in running seawater aquaria. However, surprisingly little attention is given to the nutrient composition of the water flowing through these systems, which is generally assumed to equal in situ conditions, but may change due to the presence of biofouling organisms. Significantly lower bacterial abundances and higher inorganic nitrogen species (nitrate, nitrite, and ammonium) were measured in aquarium water when biofouling organisms were present within a 7-year old inlet pipe feeding a tropical reef running seawater aquaria system, compared with aquarium water fed by a new, biofouling-free inlet pipe. These water quality changes are indicative of the feeding activity and waste production of the suspension- and filter-feeding communities found in the old pipe, which included sponges, bivalves, barnacles, and ascidians. To illustrate the physiological consequences of these water quality changes on a model organism kept in the aquaria system, we investigated the influence of the presence and absence of the biofouling community on the functioning of the filter-feeding sponge Halisarca caerulea, by determining its choanocyte (filter cell) proliferation rates. We found a 34% increase in choanocyte proliferation rates following the replacement of the inlet pipe (i.e., removal of the biofouling community). This indicates that the physiological functioning of the sponge was compromised due to suboptimal food conditions within the aquarium resulting from the presence of the biofouling organisms in the inlet pipe. This study has implications for the husbandry and performance of experiments with marine organisms in running seawater aquaria systems. Inlet pipes should be checked regularly, and replaced if necessary, in order to avoid excessive biofouling and to approach in situ water quality. PMID:26664799

  5. 46 CFR 45.155 - Inlets and discharge piping: Valves.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... means for closing at the shell if the controls are readily accessible and have indicators showing when... have— (1) An automatic nonreturn valve with a positive means for closing; or (2) Two automatic... show when the valve is not closed. (c) If the pipe discharges from a space that is not manned or...

  6. 46 CFR 45.155 - Inlets and discharge piping: Valves.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... means for closing at the shell if the controls are readily accessible and have indicators showing when... have— (1) An automatic nonreturn valve with a positive means for closing; or (2) Two automatic... show when the valve is not closed. (c) If the pipe discharges from a space that is not manned or...

  7. 46 CFR 45.155 - Inlets and discharge piping: Valves.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... means for closing at the shell if the controls are readily accessible and have indicators showing when... have— (1) An automatic nonreturn valve with a positive means for closing; or (2) Two automatic... show when the valve is not closed. (c) If the pipe discharges from a space that is not manned or...

  8. Cooling Air Inlet and Exit Geometries on Aircraft Engine Installations

    NASA Technical Reports Server (NTRS)

    Katz, Joseph; Corsiglia, Victor R.; Barlow, Philip R.

    1982-01-01

    A semispan wing and nacelle of a typical general aviation twin-engine aircraft was tested to evaluate the cooling capability and drag or several nacelle shapes; the nacelle shapes included cooling air inlet and exit variations. The tests were conducted in the Ames Research Center 40 x 80-ft Wind Tunnel. It was found that the cooling air inlet geometry of opposed piston engine installations has a major effect on inlet pressure recovery, but only a minor effect on drag. Exit location showed large effect on drag, especially for those locations on the sides of the nacelle where the suction characteristics were based on interaction with the wing surface pressures.

  9. 46 CFR 42.15-50 - Air pipes.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 2 2010-10-01 2010-10-01 false Air pipes. 42.15-50 Section 42.15-50 Shipping COAST... Conditions of Assignment of Freeboard § 42.15-50 Air pipes. (a) Where air pipes to ballast and other tanks.... Satisfactory means permanently attached, shall be provided for closing the openings of the air pipes....

  10. 46 CFR 42.15-50 - Air pipes.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 2 2011-10-01 2011-10-01 false Air pipes. 42.15-50 Section 42.15-50 Shipping COAST... Conditions of Assignment of Freeboard § 42.15-50 Air pipes. (a) Where air pipes to ballast and other tanks.... Satisfactory means permanently attached, shall be provided for closing the openings of the air pipes....

  11. Alpha-environmental continuous air monitor inlet

    DOEpatents

    Rodgers, John C.

    2003-01-01

    A wind deceleration and protective shroud that provides representative samples of ambient aerosols to an environmental continuous air monitor (ECAM) has a cylindrical enclosure mounted to an input on the continuous air monitor, the cylindrical enclosure having shrouded nozzles located radially about its periphery. Ambient air flows, often along with rainwater flows into the nozzles in a sampling flow generated by a pump in the continuous air monitor. The sampling flow of air creates a cyclonic flow in the enclosure that flows up through the cylindrical enclosure until the flow of air reaches the top of the cylindrical enclosure and then is directed downward to the continuous air monitor. A sloped platform located inside the cylindrical enclosure supports the nozzles and causes any moisture entering through the nozzle to drain out through the nozzles.

  12. 47. View of "dry air inlets" to waveguides entering scanner ...

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

    47. View of "dry air inlets" to waveguides entering scanner building 105. Dried air is generated under pressure by Ingersoll-Rand dehumidified/dessicator and compressor system. View is at entrance from passageway that links into corner of scanner building. - Clear Air Force Station, Ballistic Missile Early Warning System Site II, One mile west of mile marker 293.5 on Parks Highway, 5 miles southwest of Anderson, Anderson, Denali Borough, AK

  13. 40 CFR 81.54 - Cook Inlet Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Quality Control Regions § 81.54 Cook Inlet Intrastate Air Quality Control Region. The Cook Inlet Intrastate Air Quality Control Region (Alaska) consists of the territorial area encompassed by the boundaries... 40 Protection of Environment 18 2012-07-01 2012-07-01 false Cook Inlet Intrastate Air...

  14. 40 CFR 81.54 - Cook Inlet Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Quality Control Regions § 81.54 Cook Inlet Intrastate Air Quality Control Region. The Cook Inlet Intrastate Air Quality Control Region (Alaska) consists of the territorial area encompassed by the boundaries... 40 Protection of Environment 18 2014-07-01 2014-07-01 false Cook Inlet Intrastate Air...

  15. 40 CFR 81.54 - Cook Inlet Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Quality Control Regions § 81.54 Cook Inlet Intrastate Air Quality Control Region. The Cook Inlet Intrastate Air Quality Control Region (Alaska) consists of the territorial area encompassed by the boundaries... 40 Protection of Environment 18 2013-07-01 2013-07-01 false Cook Inlet Intrastate Air...

  16. The effect of inlet air vitiation on combustion efficiency

    SciTech Connect

    Zuomin, F.; Yijun, J.

    1985-01-01

    Experimental results of the effect of inlet air vitiation produced by a vitiating preheater on combustion efficiency of a turbojet combustor and a model ramjet combustor are presented in this paper. An empirical correlation and a calculation method based on stirred reactor theory are derived to correct the vitiation effect. Results obtained by means of these two methods are in good agreement with test data.

  17. 40 CFR 81.54 - Cook Inlet Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 17 2011-07-01 2011-07-01 false Cook Inlet Intrastate Air Quality...) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.54 Cook Inlet Intrastate Air Quality Control Region. The Cook...

  18. 40 CFR 81.54 - Cook Inlet Intrastate Air Quality Control Region.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 17 2010-07-01 2010-07-01 false Cook Inlet Intrastate Air Quality...) AIR PROGRAMS (CONTINUED) DESIGNATION OF AREAS FOR AIR QUALITY PLANNING PURPOSES Designation of Air Quality Control Regions § 81.54 Cook Inlet Intrastate Air Quality Control Region. The Cook...

  19. Investigation of Aerodynamic and Icing Characteristics of a Flush Alternate Inlet Induction System Air Scoop

    NASA Technical Reports Server (NTRS)

    Lewis, James P.

    1953-01-01

    An investigation has been made in the NACA Lewis icing research tunnel to determine the aerodynamic and icing characteristics of a full-scale induction-system air-scoop assembly incorporating a flush alternate inlet. The flush inlet was located immediately downstream of the offset ram inlet and included a 180 deg reversal and a 90 deg elbow in the ducting between inlet and carburetor top deck. The model also had a preheat-air inlet. The investigation was made over a range of mass-air- flow ratios of 0 to 0.8, angles of attack of 0 and 4 deg airspeeds of 150 to 270 miles per hour, air temperatures of 0 and 25 F various liquid-water contents, and droplet sizes. The ram inlet gave good pressure recovery in both clear air and icing but rapid blockage of the top-deck screen occurred during icing. The flush alternate inlet had poor pressure recovery in both clear air and icing. The greatest decreases in the alternate-inlet pressure recovery were obtained at icing conditions of low air temperature and high liquid-water content. No serious screen icing was observed with the alternate inlet. Pressure and temperature distributions on the carburetor top deck were determined using the preheat-air supply with the preheat- and alternate-inlet doors in various positions. No screen icing occurred when the preheat-air system was operated in combination with alternate-inlet air flow.

  20. Surface cooling of scramjet engine inlets using heat pipe, transpiration, and film cooling

    SciTech Connect

    Modlin, J.M.; Colwell, G.T. Georgia Institute of Technology, Atlanta )

    1992-09-01

    This article reports the results of applying a finite-difference-based computational technique to the problem of predicting the transient thermal behavior of a scramjet engine inlet exposed to a typical hypersonic flight aerodynamic surface heating environment, including type IV shock interference heating. The leading-edge cooling model utilized incorporates liquid metal heat pipe cooling with surface transpiration and film cooling. Results include transient structural temperature distributions, aerodynamic heat inputs, and surface coolant distributions. It seems that these cooling techniques may be used to hold maximum skin temperatures to near acceptable values during the severe aerodynamic and type IV shock interference heating effects expected on the leading edge of a hypersonic aerospace vehicle scramjet engine. 15 refs.

  1. Swozzle based burner tube premixer including inlet air conditioner for low emissions combustion

    DOEpatents

    Tuthill, Richard Sterling; Bechtel, II, William Theodore; Benoit, Jeffrey Arthur; Black, Stephen Hugh; Bland, Robert James; DeLeonardo, Guy Wayne; Meyer, Stefan Martin; Taura, Joseph Charles; Battaglioli, John Luigi

    2002-01-01

    A burner for use in a combustion system of a heavy-duty industrial gas turbine includes a fuel/air premixer having an air inlet, a fuel inlet, and an annular mixing passage. The fuel/air premixer mixes fuel and air into a uniform mixture for injection into a combustor reaction zone. The burner also includes an inlet flow conditioner disposed at the air inlet of the fuel/air premixer for controlling a radial and circumferential distribution of incoming air. The pattern of perforations in the inlet flow conditioner is designed such that a uniform air flow distribution is produced at the swirler inlet annulus in both the radial and circumference directions. The premixer includes a swozzle assembly having a series of preferably air foil shaped turning vanes that impart swirl to the airflow entering via the inlet flow conditioner. Each air foil contains internal fuel flow passages that introduce natural gas fuel into the air stream via fuel metering holes that pass through the walls of the air foil shaped turning vanes. By injecting fuel in this manner, an aerodynamically clean flow field is maintained throughout the premixer. By injecting fuel via two separate passages, the fuel/air mixture strength distribution can be controlled in the radial direction to obtain optimum radial concentration profiles for control of emissions, lean blow outs, and combustion driven dynamic pressure activity as machine and combustor load are varied.

  2. 78. PIPING CHANNEL FOR FUEL LOADING, FUEL TOPPING, COMPRESSED AIR, ...

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

    78. PIPING CHANNEL FOR FUEL LOADING, FUEL TOPPING, COMPRESSED AIR, GASEOUS NITROGEN, AND HELIUM - Vandenberg Air Force Base, Space Launch Complex 3, Launch Pad 3 East, Napa & Alden Roads, Lompoc, Santa Barbara County, CA

  3. DETAIL OF REPRESSURIZATION AIR PIPE, ALTITUDE CHAMBER L, FACING SOUTHWEST ...

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

    DETAIL OF RE-PRESSURIZATION AIR PIPE, ALTITUDE CHAMBER L, FACING SOUTHWEST - Cape Canaveral Air Force Station, Launch Complex 39, Altitude Chambers, First Street, between Avenue D and Avenue E, Cape Canaveral, Brevard County, FL

  4. Compressed air piping, 241-SY-101 hydraulic pump retrieval trailer

    SciTech Connect

    Wilson, T.R.

    1994-12-12

    The following Design Analysis was prepared by the Westinghouse Hanford Company to determine pressure losses in the compressed air piping installed on the hydraulic trailer for the 241-SY-101 pump retrieval mission.

  5. 27. EXTENSION OF SURGE CHAMBER AND AIR PIPES TO PRESSURE ...

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

    27. EXTENSION OF SURGE CHAMBER AND AIR PIPES TO PRESSURE LINE, HIGHLINE PUMPING PLANT. December 11, 1920 - Highline Canal & Pumping Station, South side of Salt River between Tempe, Phoenix & Mesa, Tempe, Maricopa County, AZ

  6. Inlet boundary conditions for shock wave propagation problems in air ducts

    NASA Astrophysics Data System (ADS)

    Fashbaugh, R. H.

    1992-03-01

    Shock waves propagating into air ducting systems are numerically studied using data from Kriebel (1972). Small-scale junctions mounted in shock tubes with an incident shock wave are considered. The stagnation pressure ratio through a duct inlet is evaluated for various junction types. The logarithm of this ratio varies linearly with the Mach number of the flow behind the incident shock wave. The static pressure inside the inlet is established using experimental data with given Mach numbers of the incident and inlet flows. A constant stagnation enthalpy through the inlet junction is assumed to establish inflow to the duct.

  7. Analytical and experimental study on complex compressed air pipe network

    NASA Astrophysics Data System (ADS)

    Gai, Yushou; Cai, Maolin; Shi, Yan

    2015-09-01

    To analyze the working characteristics of complex compressed air networks, numerical methods are widely used which are based on finite element technology or intelligent algorithms. However, the effectiveness of the numerical methods is limited. In this paper, to provide a new method to optimize the design and the air supply strategy of the complex compressed air pipe network, firstly, a novel method to analyze the topology structure of the compressed air flow in the pipe network is initially proposed. A matrix is used to describe the topology structure of the compressed air flow. Moreover, based on the analysis of the pressure loss of the pipe network, the relationship between the pressure and the flow of the compressed air is derived, and a prediction method of pressure fluctuation and air flow in a segment in a complex pipe network is proposed. Finally, to inspect the effectiveness of the method, an experiment with a complex network is designed. The pressure and the flow of airflow in the network are measured and studied. The results of the study show that, the predicted results with the proposed method have a good consistency with the experimental results, and that verifies the air flow prediction method of the complex pipe network. This research proposes a new method to analyze the compressed air network and a prediction method of pressure fluctuation and air flow in a segment, which can predicate the fluctuation of the pressure according to the flow of compressed air, and predicate the fluctuation of the flow according to the pressure in a segment of a complex pipe network.

  8. Advantages of air conditioning and supercharging an LM6000 gas turbine inlet

    SciTech Connect

    Kolp, D.A.; Flye, W.M.; Guidotti, H.A.

    1995-07-01

    Of all the external factors affecting a gas turbine, inlet pressure and temperature have the greatest impact on performance. The effect of inlet temperature variations is especially pronounced in the new generation of high-efficiency gas turbines typified by the 40 MW GE LM6000. A reduction of 50 F (28 C) in inlet temperature can result in a 30 percent increase in power and a 4.5 percent improvement in heat rate. An elevation increase to 5,000 ft (1,524 m) above sea level decreases turbine output 17 percent; conversely supercharging can increase output more than 20 percent. This paper addresses various means of heating, cooling and supercharging LM6000 inlet air. An economic model is developed and sample cases are cited to illustrate the optimization of gas turbine inlet systems, taking into account site conditions, incremental equipment cost and subsequent performance enhancement.

  9. Fluid flow and heat transfer in an air-to-water double-pipe heat exchanger

    NASA Astrophysics Data System (ADS)

    Sheikholeslami, M.; Gorji-Bandpy, M.; Ganji, D. D.

    2015-11-01

    This paper reports experimental and numerical investigations on flow and heat transfer in an air-to-water double-pipe heat exchanger. The working fluids are air and water. To achieve fully developed conditions, the heat exchanger was built with additional lengths before and after the test section. The inner and outer tube was made from copper and Plexiglas, respectively. The experiments are conducted in the range of air flow Reynolds number for various cases with different water flow rate and water inlet temperature. Correlations for the Nusselt number and friction factor are presented according to experimental data. Also the commercial code ANSYS 15 is used for numerical simulation. Results show that the Nusselt number is an increasing function of Reynolds number and Prandtl number which are calculated at bulk temperature.

  10. Aerodynamic characteristics of a series of twin-inlet air-breathing missile configurations. 2: Two-dimensional inlets at supersonic speeds

    NASA Technical Reports Server (NTRS)

    Hayes, C.

    1983-01-01

    A series of air-breathing missile configurations was investigated to provide a data base for the design of such missiles. The model could be configured with either twin axisymmetric or two dimensional inlets. Three circumferential inlet locations were investigated: 90 deg, 115 deg, and 135 deg from the top center. Two vertical wing locations, as well as wingless configurations, were used. Three tail configurations were formed by locating the tail surfaces either on the inlet fairings or on fairings on the body. The surfaces were used to provide pitch control. Two dimensional inlets with extended compression surfaces, used to improve the angle-of-attack performance of the inlets for wingless configurations, were also investigated. The two dimensional inlet configurations are covered.

  11. Aerodynamic characteristics of a series of single-inlet air-breathing missile configurations

    NASA Technical Reports Server (NTRS)

    Hayes, C.

    1983-01-01

    A series of air-breathing missile configurations was investigated to provide a data base for the design of such missiles. The model could be configured with either a single axisymmetric or a two dimensional inlet located at the bottom of the body. Two tail configurations were investigated: a tri-tail and an X-tail. The tail surfaces could be deflected to provide pitch control. A wing could be located above the inlet on the center line of the model. Tests were made at supersonic Mach numbers with the inlet open and internal flow, and at subsonic-transonic Mach numbers with the internal duct closed and no internal flow.

  12. Effect of inlet-air humidity on the formation of oxides of nitrogen in a gas-turbine combustor

    NASA Technical Reports Server (NTRS)

    Marchionna, N. R.

    1973-01-01

    Tests were conducted to determine the effect of inlet-air humidity on the formation of oxides of nitrogen from a gas-turbine combustor. Combustor inlet-air temperature ranged from 450 F to 1050 F. The tests were run at a constant pressure of 6 atmospheres and reference Mach number of 0.065. The NO sub x emission index was found to decrease with increasing inlet-air humidity at a constant exponential rate of 19 percent per mass percent water vapor in the air. This decrease of NO sub x emission index with increasing humidity was found to be independent of inlet-air temperature.

  13. Apparatus and Method for Measuring Air Temperature Ahead of an Aircraft for Controlling a Variable Inlet/Engine Assembly

    NASA Technical Reports Server (NTRS)

    Gary, Bruce L. (Inventor)

    2001-01-01

    The apparatus and method employ remote sensing to measure the air temperature a sufficient distance ahead of the aircraft to allow time for a variable inlet/engine assembly to be reconfigured in response to the measured temperature, to avoid inlet unstart and/or engine compressor stall. In one embodiment, the apparatus of the invention has a remote sensor for measuring at least one air temperature ahead of the vehicle and an inlet control system for varying the inlet. The remote sensor determines a change in temperature value using at least one temperature measurement and prior temperature measurements corresponding to the location of the aircraft. The control system uses the change in air temperature value to vary the inlet configuration to maintain the position of the shock wave during the arrival of the measured air in the inlet. In one embodiment, the method of the invention includes measuring at least one air temperature ahead of the vehicle, determining an air temperature at the vehicle from prior air temperature measurements, determining a change in temperature value using the air temperature at the vehicle and the at least one air temperature measurement ahead of the vehicle, and using the change in temperature value to-reposition the airflow inlet, to cause the shock wave to maintain substantially the same position within the inlet as the airflow temperature changes within the inlet.

  14. Improving the performance of a compression ignition engine by directing flow of inlet air

    NASA Technical Reports Server (NTRS)

    Kemper, Carlton

    1946-01-01

    The object of this report is to present the results of tests performed by the National Advisory Committee for Aeronautics to determine the effect on engine performance of directing the flow of the inlet air to a 5-inch by 7-inch cylinder, solid injection, compression ignition engine, After a few preliminary tests, comparative runs were made at a speed of 1500 r.p.m. with and without directed air flow. It was found that directing the flow of the inlet air toward the fuel injection valve gave steadier engine operation, and an appreciable increase in power, and decreased fuel consumption. The results indicate the possibility of improving the performance of a given type of combustion chamber without changing its shape and with no change in valve timing. They would also seem to prove that directional turbulence, set up before the inlet valve of a four-stroke cycle engine, continues in the engine cylinder throughout the compression stroke.

  15. A comparative assessment of alternative combustion turbine inlet air cooling system

    SciTech Connect

    Brown, D.R.; Katipamula, S.; Konynenbelt, J.H.

    1996-02-01

    Interest in combustion turbine inlet air cooling (CTAC) has increased during the last few years as electric utilities face increasing demand for peak power. Inlet air cooling increases the generating capacity and decreases the heat rate of a combustion turbine during hot weather when the demand for electricity is generally the greatest. Several CTAC systems have been installed, but the general applicability of the concept and the preference for specific concepts is still being debated. Concurrently, Rocky Research of Boulder City, Nevada has been funded by the U.S. Department of Energy to conduct research on complex compound (ammoniated salt) chiller systems for low-temperature refrigeration applications.

  16. Problems in creation of modern air inlet filters of power gas turbine plants in Russia and methods of their solving

    NASA Astrophysics Data System (ADS)

    Mikhaylov, V. E.; Khomenok, L. A.; Sherapov, V. V.

    2016-08-01

    The main problems in creation and operation of modern air inlet paths of gas turbine plants installed as part of combined-cycle plants in Russia are presented. It is noted that design features of air inlet filters shall be formed at the stage of the technical assignment not only considering the requirements of gas turbine plant manufacturer but also climatic conditions, local atmospheric air dustiness, and a number of other factors. The recommendations on completing of filtration system for air inlet filter of power gas turbine plants depending on the facility location are given, specific defects in design and experience in operation of imported air inlet paths are analyzed, and influence of cycle air preparation quality for gas turbine plant on value of operating expenses and cost of repair works is noted. Air treatment equipment of various manufacturers, influence of aerodynamic characteristics on operation of air inlet filters, features of filtration system operation, anti-icing system, weather canopies, and other elements of air inlet paths are considered. It is shown that nonuniformity of air flow velocity fields in clean air chamber has a negative effect on capacity and aerodynamic resistance of air inlet filter. Besides, the necessity in installation of a sufficient number of differential pressure transmitters allowing controlling state of each treatment stage not being limited to one measurement of total differential pressure in the filtration system is noted in the article. According to the results of the analysis trends and methods for modernization of available equipment for air inlet path, the importance of creation and implementation of new technologies for manufacturing of filtering elements on sites of Russia within the limits of import substitution are given, and measures on reliability improvement and energy efficiency for air inlet filter are considered.

  17. Operational test report for 241-AW tank inlet air control stations

    SciTech Connect

    Minteer, D.J., Westinghouse Hanford

    1996-07-03

    This document reports the results of operational testing on tank inlet air control stations in 241-AW tank farm. An air control station was installed on each of the six AW tanks. Operational testing consisted of a simple functional test of each station`s air flow controller, aerosol testing of each station`s HEPA filter, and final ventilation system balancing (i.e., tank airflows and vacuum level) using the air control stations. The test was successful and the units were subsequently placed into operation.

  18. The Role of Design-of-Experiments in Managing Flow in Compact Air Vehicle Inlets

    NASA Technical Reports Server (NTRS)

    Anderson, Bernhard H.; Miller, Daniel N.; Gridley, Marvin C.; Agrell, Johan

    2003-01-01

    It is the purpose of this study to demonstrate the viability and economy of Design-of-Experiments methodologies to arrive at microscale secondary flow control array designs that maintain optimal inlet performance over a wide range of the mission variables and to explore how these statistical methods provide a better understanding of the management of flow in compact air vehicle inlets. These statistical design concepts were used to investigate the robustness properties of low unit strength micro-effector arrays. Low unit strength micro-effectors are micro-vanes set at very low angles-of-incidence with very long chord lengths. They were designed to influence the near wall inlet flow over an extended streamwise distance, and their advantage lies in low total pressure loss and high effectiveness in managing engine face distortion. The term robustness is used in this paper in the same sense as it is used in the industrial problem solving community. It refers to minimizing the effects of the hard-to-control factors that influence the development of a product or process. In Robustness Engineering, the effects of the hard-to-control factors are often called noise , and the hard-to-control factors themselves are referred to as the environmental variables or sometimes as the Taguchi noise variables. Hence Robust Optimization refers to minimizing the effects of the environmental or noise variables on the development (design) of a product or process. In the management of flow in compact inlets, the environmental or noise variables can be identified with the mission variables. Therefore this paper formulates a statistical design methodology that minimizes the impact of variations in the mission variables on inlet performance and demonstrates that these statistical design concepts can lead to simpler inlet flow management systems.

  19. Benefits of compressor inlet air cooling for gas turbine cogeneration plants

    SciTech Connect

    De Lucia, M.; Lanfranchi, C.; Boggio, V.

    1996-07-01

    Compressor inlet air cooling is an effective method for enhancing the performance of gas turbine plants. This paper presents a comparative analysis of different solutions for cooling the compressor inlet air for the LM6000 gas turbine in a cogeneration plant operated in base load. Absorption and evaporative cooling systems are considered and their performance and economic benefits compared for the dry low-NO{sub x} LM6000 version. Reference is made to two sites in Northern and Southern Italy, whose climate data series for modeling the variations in ambient temperature during the single day were used to account for the effects of climate in the simulation. The results confirmed the advantages of inlet air cooling systems. In particular, evaporative cooling proved to be cost effective, though capable of supplying only moderate cooling, while absorption systems have a higher cost but are also more versatile and powerful in base-load operation. An integration of the two systems proved to be able to give both maximum performance enhancement and net economic benefit.

  20. Wind-Tunnel Investigation of Air Inlet and Outlet Openings on a Streamline Body

    NASA Technical Reports Server (NTRS)

    Becker, John V

    1951-01-01

    In connection with the general problem of providing air flow to an aircraft power plant located within a fuselage, an investigation was conducted in the Langley 8-foot high-speed tunnel to determine the effect on external drag and pressure distribution of air inlet openings located at the nose of a streamline body. Air outlet openings located at the tail and at the 21-percent and 63-percent stations of the body were also investigated. Boundary layer transition measurements were made and correlated with the force and the pressure data. Individual openings were investigated with the aid of a blower and then practicable combinations of inlet and outlet openings were tested. Various modifications to the internal duct shape near the inlet opening and the aerodynamic effects of a simulated gun in the duct were also studied. The results of the tests suggested that outlet openings should be designed so that the static pressure of the internal flow at the outlet would be the same as the static pressure of the external flow in the vicinity of the opening.

  1. Environmental continuous air monitor inlet with combined preseparator and virtual impactor

    DOEpatents

    Rodgers, John C.

    2007-06-19

    An inlet for an environmental air monitor is described wherein a pre-separator interfaces with ambient environment air and removes debris and insects commonly associated with high wind outdoors and a deflector plate in communication with incoming air from the pre-separator stage, that directs the air radially and downward uniformly into a plurality of accelerator jets located in a manifold of a virtual impactor, the manifold being cylindrical and having a top, a base, and a wall, with the plurality of accelerator jets being located in the top of the manifold and receiving the directed air and accelerating directed air, thereby creating jets of air penetrating into the manifold, where a major flow is deflected to the walls of the manifold and extracted through ports in the walls. A plurality of receiver nozzles are located in the base of the manifold coaxial with the accelerator jets, and a plurality of matching flow restrictor elements are located in the plurality of receiver nozzles for balancing and equalizing the total minor flow among all the plurality of receiver nozzles, through which a lower, fractional flow extracts large particle constituents of the air for collection on a sample filter after passing through the plurality of receiver nozzles and the plurality of matching flow restrictor elements.

  2. Design Evolution and Performance Characterization of the GTX Air-Breathing Launch Vehicle Inlet

    NASA Technical Reports Server (NTRS)

    DeBonis, J. R.; Steffen, C. J., Jr.; Rice, T.; Trefny, C. J.

    2002-01-01

    The design and analysis of a second version of the inlet for the GTX rocket-based combine-cycle launch vehicle is discussed. The previous design did not achieve its predicted performance levels due to excessive turning of low-momentum comer flows and local over-contraction due to asymmetric end-walls. This design attempts to remove these problems by reducing the spike half-angle to 10- from 12-degrees and by implementing true plane of symmetry end-walls. Axisymmetric Reynolds-Averaged Navier-Stokes simulations using both perfect gas and real gas, finite rate chemistry, assumptions were performed to aid in the design process and to create a comprehensive database of inlet performance. The inlet design, which operates over the entire air-breathing Mach number range from 0 to 12, and the performance database are presented. The performance database, for use in cycle analysis, includes predictions of mass capture, pressure recovery, throat Mach number, drag force, and heat load, for the entire Mach range. Results of the computations are compared with experimental data to validate the performance database.

  3. Nonuniform air flow in inlets: the effect on filter deposits in the fiber sampling cassette.

    PubMed

    Baron, P A; Chen, C C; Hemenway, D R; O'Shaughnessy, P

    1994-08-01

    Smoke stream studies were combined with a new technique for visualizing a filter deposit from samples used to monitor asbestos or other fibers. Results clearly show the effect of secondary flow vortices within the sampler under anisoaxial sampling conditions. The vortices observed at low wind velocities occur when the inlet axis is situated at angles between 45 degrees and 180 degrees to the motion of the surrounding air. It is demonstrated that the vortices can create a complex nonuniform pattern in the filter deposit, especially when combined with particle settling or electrostatic interactions between the particles and the sampler. Inertial effects also may play a role in the deposit nonuniformity, as well as causing deposition on the cowl surfaces. Changes in the sampler, such as its placement, may reduce these biases. The effects noted are not likely to occur in all sampling situations, but may explain some reports of high variability on asbestos fiber filter samples. The flow patterns observed in this study are applicable to straight, thin-walled inlets. Although only compact particles were used, the air flow patterns and forces involved will have similar effects on fibers of the same aerodynamic diameter.

  4. 49 CFR 179.220-17 - Gauging devices, top loading and unloading devices, venting and air inlet devices.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 3 2011-10-01 2011-10-01 false Gauging devices, top loading and unloading devices, venting and air inlet devices. 179.220-17 Section 179.220-17 Transportation Other Regulations Relating to... and 115AW) § 179.220-17 Gauging devices, top loading and unloading devices, venting and air...

  5. 241-U-701 new compressor building and instrument air piping analyses

    SciTech Connect

    Huang, F.H.

    1994-08-25

    Building anchorage analysis is performed to qualify the design of the new compressor building foundation given in the ECN ``241-U-701 New Compressor Building.`` Recommendations for some changes in the ECN are made accordingly. Calculations show that the 6-in.-slab is capable of supporting the pipe supports, and that the building foundation, air compressor and dryer anchorage, and electric rack are adequate structurally. Analysis also shows that the instrument air piping and pipe supports for the compressed air system meet the applicable code requirements and are acceptable. The building is for the U-Farm instrument air systems.

  6. Performance and economic enhancement of cogeneration gas turbines through compressor inlet air cooling

    NASA Astrophysics Data System (ADS)

    Delucia, M.; Bronconi, R.; Carnevale, E.

    1994-04-01

    Gas turbine air cooling systems serve to raise performance to peak power levels during the hot months when high atmospheric temperatures cause reductions in net power output. This work describes the technical and economic advantages of providing a compressor inlet air cooling system to increase the gas turbine's power rating and reduce its heat rate. The pros and cons of state-of-the-art cooling technologies, i.e., absorption and compression refrigeration, with and without thermal energy storage, were examined in order to select the most suitable cooling solution. Heavy-duty gas turbine cogeneration systems with and without absorption units were modeled, as well as various industrial sectors, i.e., paper and pulp, pharmaceuticals, food processing, textiles, tanning, and building materials. The ambient temperature variations were modeled so the effects of climate could be accounted for in the simulation. The results validated the advantages of gas turbine cogeneration with absorption air cooling as compared to other systems without air cooling.

  7. Air-sampling inlet contamination by aircraft emissions on the NASA CV-990 aircraft

    NASA Technical Reports Server (NTRS)

    Condon, E. P.; Vedder, J. F.

    1984-01-01

    Results of an experimental investigation of the contamination of air sampling inlets by aircraft emissions from the NASA CV-990 research aircraft are presented. This four-engine jet aircraft is a NASA facility used for many different atmospheric and meteorological experiments, as well as for developing spacecraft instrumentation for remote measurements. Our investigations were performed to provide information on which to base the selection of sampling locations for a series of multi-instrument missions for measuring tropospheric trace gases. The major source of contamination is the exhaust from the jet engines, which generate many of the same gases that are of interest in atmospheric chemistry, as well as other gases that may interfere with sampling measurements. The engine exhaust contains these gases in mixing ratios many orders of magnitude greater than those that occur in the clean atmosphere which the missions seek to quantify. Pressurized samples of air were collected simultaneously from a scoop located forward of the engines to represent clean air and from other multiport scoops at various aft positions on the aircraft. The air samples were analyzed in the laboratory by gas chromatography for carbon monoxide, an abundant combustion by-product. Data are presented for various scoop locations under various flight conditions.

  8. Numerical Investigation of Engine Inlet Vane Hot-Air Anti-Icing System with Surface Air Film

    NASA Astrophysics Data System (ADS)

    Ma, Hui; Chen, Weijian; Zhang, Dalin

    The inlet vane of aircraft engine needs to be equipped with anti-icing system to prevent ice accretion on the leading edge due to flight safety requirements, and the engine bleed hot-air is mostly used to heat the vane surface in anti-icing system. In order to save the energy consumption, a new anti-icing structure was developed and investigated with numerical simulation. Besides the use of small tunnels to enhance the heat transfer characteristics, a narrow gap was opened and assigned on the vane surface at the end of the anti-icing tunnels, and the exhaust hot-air was released from the gap to form an air film on the outside surface, which was supposed to prevent the droplets from impinging to the surface and sweep the droplets away. The droplets impingement on the vane surface was investigated by solving the 3D Eulerian air/droplets twophase model, and the impingement results were compared with the original system. Meanwhile, the thermodynamic analysis of the anti-icing system was presented in this paper. The results indicate that the air film is effective to decrease the droplets impingement area, and the new structure could provide more heat flux for anti-icing than the regular anti-icing structure.

  9. Effect of Fuel-Air Ratio, Inlet Temperature, and Exhaust Pressure on Detonation

    NASA Technical Reports Server (NTRS)

    Taylor, E S; Leary, W A; Diver, J R

    1940-01-01

    An accurate determination of the end-gas condition was attempted by applying a refined method of analysis to experimental results. The results are compared with those obtained in Technical Report no. 655. The experimental technique employed afforded excellent control over the engine variables and unusual cyclic reproducibility. This, in conjunction with the new analysis, made possible the determination of the state of the end-gas at any instant to a fair degree of precision. Results showed that for any given maximum pressure the maximum permissible end-gas temperature increased as the fuel-air ratio was increased. The tendency to detonate was slightly reduced by an increase in residual gas content resulting from an increase in exhaust backpressure with inlet pressure constant.

  10. The comparative performance of an aviation engine at normal and high inlet air temperatures

    NASA Technical Reports Server (NTRS)

    Gardiner, Arthur W; Schey, Oscar W

    1928-01-01

    This report presents some results obtained during an investigation to determine the effect of high inlet air temperature on the performance of a Liberty 12 aviation engine. The purpose of this investigation was to ascertain, for normal service carburetor adjustments and a fixed ignition advance, the relation between power and temperature for the range of carburetor air temperatures that may be encountered when supercharging to sea level pressure at altitudes of over 20,000 feet and without intercooling when using plain aviation gasoline and mixtures of benzol and gasoline. The results show that for the conditions of test, both the brake and indicated power decrease with increase in air temperature at a faster rate than given by the theoretical assumption that power varies inversely as the square root of the absolute temperature. On a brake basis, the order of the difference in power for a temperature difference of 120 degrees F. Is 3 to 5 per cent. The observed relation between power and temperature when using the 30-70 blend was found to be linear. But, although these differences are noted, the above theoretical assumption may be considered as generally applicable except where greater precision over a wide range of temperatures is desired, in which case it appears necessary to test the particular engine under the given conditions. (author)

  11. Design of passively aerated compost piles: Vertical air velocities between the pipes

    SciTech Connect

    Lynch, N.J.; Cherry, R.S.

    1996-09-01

    Passively aerated compost piles are built on a base of porous materials, such as straw or wood chips, in which perforated air supply pipes are distributed. The piles are not turned during composting, nor is forced-aeration equipment used, which significantly reduces the operating and capital expenses associated with these piles. Currently, pile configurations and materials are worked out by trial and error. Fundamentally based design procedures are difficult to develop because the natural convection air flow rate is not explicitly known, but rather is closely coupled with the pile temperature. This paper develops a mathematical model to analytically determine the maximum upward air flow velocity over an air supply pipe and the drop in vertical velocity away from the pipe. This model has one dimensionless number, dependent on the pile and base properties, which fully characterizes the velocity profile between the pipes. 9 refs., 4 figs., 1 tab.

  12. 49 CFR 179.200-16 - Gauging devices, top loading and unloading devices, venting and air inlet devices.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 3 2011-10-01 2011-10-01 false Gauging devices, top loading and unloading devices... and 115AW) § 179.200-16 Gauging devices, top loading and unloading devices, venting and air inlet...). In no case shall the wall thickness be less than that specified in § 179.201-1. (f) When top...

  13. 49 CFR 179.220-17 - Gauging devices, top loading and unloading devices, venting and air inlet devices.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Gauging devices, top loading and unloading devices, venting and air inlet devices. 179.220-17 Section 179.220-17 Transportation Other Regulations Relating to... DOT-111AW and 115AW) § 179.220-17 Gauging devices, top loading and unloading devices, venting and...

  14. 49 CFR 179.200-16 - Gauging devices, top loading and unloading devices, venting and air inlet devices.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 3 2012-10-01 2012-10-01 false Gauging devices, top loading and unloading devices, venting and air inlet devices. 179.200-16 Section 179.200-16 Transportation Other Regulations Relating to Transportation (Continued) PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF...

  15. 49 CFR 179.220-17 - Gauging devices, top loading and unloading devices, venting and air inlet devices.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 3 2013-10-01 2013-10-01 false Gauging devices, top loading and unloading devices, venting and air inlet devices. 179.220-17 Section 179.220-17 Transportation Other Regulations Relating to Transportation (Continued) PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF...

  16. 49 CFR 179.200-16 - Gauging devices, top loading and unloading devices, venting and air inlet devices.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 3 2013-10-01 2013-10-01 false Gauging devices, top loading and unloading devices, venting and air inlet devices. 179.200-16 Section 179.200-16 Transportation Other Regulations Relating to Transportation (Continued) PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF...

  17. Bedding factors and E values for buried pipe installations backfilled with air-modified CLSM

    SciTech Connect

    McGrath, T.J.; Hoopes, R.J.

    1998-10-01

    The use of controlled low strength material (CLSM) as a pipe bedding and backfill material requires characterization in terms of traditional design parameters such as bedding factors for rigid pipe and modulus of soil reaction, or E, values for flexible pipe. Triaxial compression and one-dimensional consolidation tests were conducted on two mixes of air-modified CLSM to establish parameters for use in finite element analyses of buried pipe installations. Both trial mixes contained 25 to 30% entrained air to provide flowability. The tests were conducted at ages of 16 hours, 7 days and 28 days to evaluate the change in strength and stiffness with time. Results of the tests were analyzed to fit parameters to the Duncan hyperbolic soil model with the Selig bulk modulus model. These parameters were then used in analyses of flexible and rigid pipe installations, backfilled with CLSM, to determine traditional installation design parameters. The finite element analyses indicate that bedding factors for rigid pipe installations range from 1.8, for trench installations backfilled at an age of 16 hours, to 2.5 for trench installations backfilled at an age of 28 days. Bedding factors for embankment installations of rigid pipe range from 2.5 to 4.8 for ages from 16 hours to 28 days, respectively. Values for the modulus of soil reaction (E) for installation of flexible pipe range from 7 MPa to 21 MPa (1,000 psi to 3,000 psi) for ages from 16 hours to 28 days respectively.

  18. Development and Characterization Testing of an Air Pulsation Valve for a Pulse Detonation Engine Supersonic Parametric Inlet Test Section

    NASA Technical Reports Server (NTRS)

    Tornabene, Robert

    2005-01-01

    In pulse detonation engines, the potential exists for gas pulses from the combustor to travel upstream and adversely affect the inlet performance of the engine. In order to determine the effect of these high frequency pulses on the inlet performance, an air pulsation valve was developed to provide air pulses downstream of a supersonic parametric inlet test section. The purpose of this report is to document the design and characterization tests that were performed on a pulsation valve that was tested at the NASA Glenn Research Center 1x1 Supersonic Wind Tunnel (SWT) test facility. The high air flow pulsation valve design philosophy and analyses performed are discussed and characterization test results are presented. The pulsation valve model was devised based on the concept of using a free spinning ball valve driven from a variable speed electric motor to generate air flow pulses at preset frequencies. In order to deliver the proper flow rate, the flow port was contoured to maximize flow rate and minimize pressure drop. To obtain sharp pressure spikes the valve flow port was designed to be as narrow as possible to minimize port dwell time.

  19. Investigation of X24C-2 10-Stage Axial-Flow Compressor. 2; Effect of Inlet-Air Pressure and Temperature of Performance

    NASA Technical Reports Server (NTRS)

    Finger, Harold B.; Schum, Harold J.; Buckner, Howard Jr.

    1947-01-01

    Effect of inlet-air pressure and temperature on the performance of the X24-2 10-Stage Axial-Flow Compressor from the X24C-2 turbojet engine was evaluated. Speeds of 80, 89, and 100 percent of equivalent design speed with inlet-air pressures of 6 and 12 inches of mercury absolute and inlet-air temperaures of approximately 538 degrees, 459 degrees,and 419 degrees R ( 79 degrees, 0 degrees, and minus 40 degrees F). Results were compared with prior investigations.

  20. Experimental investigation on performance of ice storage air-conditioning system with separate heat pipe

    SciTech Connect

    Fang, Guiyin; Liu, Xu; Wu, Shuangmao

    2009-11-15

    An experimental study on operation performance of ice storage air-conditioning system with separate helical heat pipe is conducted in this paper. The experimental system of ice storage air-conditioning system with separate heat pipe is set up. The performance parameters such as the evaporation pressure and the condensation pressure of refrigeration system, the refrigeration capacity and the COP (coefficient of performance) of the system, the IPF (ice packing factor) and the cool storage capacity in the cool storage tank during charging period, and the cool discharge rate and the cool discharge capacity in the cool storage tank, the outlet water temperature in the cool storage tank and the outlet air temperature in room unit during discharging period are investigated. The experimental results show that the ice storage air-conditioning system with separate helical heat pipe can stably work during charging and discharging period. This indicates that the ice storage air-conditioning system with separate helical heat pipe is well adapted to cool storage air-conditioning systems in building. (author)

  1. The induction of water to the inlet air as a means of internal cooling in aircraft-engine cylinders

    NASA Technical Reports Server (NTRS)

    Rothrock, Addison M; Krsek, Alois, Jr; Jones, Anthony W

    1943-01-01

    Report presents the results of investigations conducted on a full-scale air-cooled aircraft-engine cylinder of 202-cubic inch displacement to determine the effects of internal cooling by water induction on the maximum permissible power and output of an internal-combustion engine. For a range of fuel-air and water-fuel ratios, the engine inlet pressure was increased until knock was detected aurally, the power was then decreased 7 percent holding the ratios constant. The data indicated that water was a very effective internal coolant, permitting large increases in engine power as limited by either knock or by cylinder temperatures.

  2. Effect of inlet-air humidity, temperature, pressure, and reference Mach number on the formation of oxides of nitrogen in a gas turbine combustor

    NASA Technical Reports Server (NTRS)

    Marchionna, N. R.; Diehl, L. A.; Trout, A. M.

    1973-01-01

    Tests were conducted to determine the effect of inlet air humidity on the formation of oxides of nitrogen (NOx) from a gas turbine combustor. Combustor inlet air temperature ranged from 506 K (450 F) to 838 K (1050 F). The tests were primarily run at a constant pressure of 6 atmospheres and reference Mach number of 0.065. The NOx emission index was found to decrease with increasing inlet air humidity at a constant exponential rate: NOx = NOx0e-19H (where H is the humidity and the subscript 0 denotes the value at zero humidity). the emission index increased exponentially with increasing normalized inlet air temperature to the 1.14 power. Additional tests made to determine the effect of pressure and reference Mach number on NOx showed that the NOx emission index varies directly with pressure to the 0.5 power and inversely with reference Mach number.

  3. 49 CFR 178.337-9 - Pressure relief devices, piping, valves, hoses, and fittings.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ..., valves, hose, and fittings. (1) The burst pressure of all piping, pipe fittings, hose and other pressure... of the cargo tank. Additionally, the burst pressure may not be less than 4 times any higher pressure... must be tested for leakage at not less than 225 psig using dry air or inert gas. (c) Marking inlets...

  4. Illustrations and Supporting Texts for Sound Standing Waves of Air Columns in Pipes in Introductory Physics Textbooks

    ERIC Educational Resources Information Center

    Zeng, Liang; Smith, Chris; Poelzer, G. Herold; Rodriguez, Jennifer; Corpuz, Edgar; Yanev, George

    2014-01-01

    In our pilot studies, we found that many introductory physics textbook illustrations with supporting text for sound standing waves of air columns in open-open, open-closed, and closed-closed pipes inhibit student understanding of sound standing wave phenomena due to student misunderstanding of how air molecules move within these pipes. Based on…

  5. Modification of Cabinet Fans with Inlet Air Guide Fairings to Improve Performance.

    DTIC Science & Technology

    1983-04-01

    CHAMPAIGN IL W H DOLAN ANLSIFE PR 83 CERL-TR-E-i~i F /G 13/1i N EIND IllIflI2.8 25 36 1111.8 1.4 L16 MICROCOPY RESOLUTION TEST CHART NATIONAL BUREAU OF...fan inlet conditions. By observing airflow within the cabinet, a DO ,~~ F 10 EDIIONOF NOV6 ISOSOETEUNCLASS IFIED SACUSSTV CLASSIFICATION OF THIS PAGE...7 F ,.vousA.F i 7$ __. DISCHARGE PLATE CONNECTING FAN WHEEL TO FAN SHAFT. ROTATING FAN WHEEL Fig.,e 1. Double Width, Double Inlet (DWDI) centrifugal

  6. Heat transfer to two-phase air/water mixtures flowing in small tubes with inlet disequilibrium

    NASA Technical Reports Server (NTRS)

    Janssen, J. M.; Florschuetz, L. W.; Fiszdon, J. P.

    1986-01-01

    The cooling of gas turbine components was the subject of considerable research. The problem is difficult because the available coolant, compressor bleed air, is itself quite hot and has relatively poor thermophysical properties for a coolant. Injecting liquid water to evaporatively cool the air prior to its contact with the hot components was proposed and studied, particularly as a method of cooling for contingency power applications. Injection of a small quantity of cold liquid water into a relatively hot coolant air stream such that evaporation of the liquid is still in process when the coolant contacts the hot component was studied. No approach was found whereby heat transfer characteristics could be confidently predicted for such a case based solely on prior studies. It was not clear whether disequilibrium between phases at the inlet to the hot component section would improve cooling relative to that obtained where equilibrium was established prior to contact with the hot surface.

  7. Optimal Micro-Vane Flow Control for Compact Air Vehicle Inlets

    NASA Technical Reports Server (NTRS)

    Anderson, Bernhard H.; Miller, Daniel N.; Addington, Gregory A.; Agrell, Johan

    2004-01-01

    The purpose of this study on micro-vane secondary flow control is to demonstrate the viability and economy of Response Surface Methodology (RSM) to optimally design micro-vane secondary flow control arrays, and to establish that the aeromechanical effects of engine face distortion can also be included in the design and optimization process. These statistical design concepts were used to investigate the design characteristics of "low unit strength" micro-effector arrays. "Low unit strength" micro-effectors are micro-vanes set at very low angles-of-incidence with very long chord lengths. They were designed to influence the near wall inlet flow over an extended streamwise distance, and their advantage lies in low total pressure loss and high effectiveness in managing engine face distortion. Therefore, this report examines optimal micro-vane secondary flow control array designs for compact inlets through a Response Surface Methodology.

  8. Wind-Tunnel Investigation of Air Inlet and Outlet Openings for Aircraft, Special Report

    NASA Technical Reports Server (NTRS)

    Rogallo, Francis M.; Gauvain, William E.

    1938-01-01

    An investigation was made in the NACA 5-foot vertical wind tunnel of a large variety of duct inlets and outlets to obtain information relative to their design for the cooling or the ventilation systems on aircraft. Most of the tests were of openings in a flat plate but, in order to determine the best locations and the effects of interference, a few tests were made of openings in an airfoil. The best inlet location for a system not including a blower was found to be at the forward stagnation point; for one including a blower, the best location was found to be in the region of lowest total head, probably in the boundary layer near the trailing edge. Design recommendations are given, and it is shown that correct design demands a knowledge of the external flow and of the internal requirements in addition to that obtained from the results of the wind tunnel tests.

  9. Management of Total Pressure Recovery, Distortion and High Cycle Fatigue in Compact Air Vehicle Inlets

    NASA Technical Reports Server (NTRS)

    Anderson, Bernhard H.; Baust, Henry D.; Agrell, Johan

    2002-01-01

    It is the purpose of this study to demonstrate the viability and economy of Response Surface Methods (RSM) and Robustness Design Concepts (RDC) to arrive at micro-secondary flow control installation designs that maintain optimal inlet performance over a range of the mission variables. These statistical design concepts were used to investigate the robustness properties of 'low unit strength' micro-effector installations. 'Low unit strength' micro-effectors are micro-vanes set at very low angles-of-incidence with very long chord lengths. They were designed to influence the near wall inlet flow over an extended streamwise distance, and their advantage lies in low total pressure loss and high effectiveness in managing engine face distortion.

  10. Effect of inlet temperature on the performance of a catalytic reactor. [air pollution control

    NASA Technical Reports Server (NTRS)

    Anderson, D. N.

    1978-01-01

    A 12 cm diameter by 15 cm long catalytic reactor was tested with No. 2 diesel fuel in a combustion test rig at inlet temperatures of 700, 800, 900, and 1000 K. Other test conditions included pressures of 3 and 6 x 10 to the 5th power Pa, reference velocities of 10, 15, and 20 m/s, and adiabatic combustion temperatures in the range 1100 to 1400 K. The combustion efficiency was calculated from measurements of carbon monoxide and unburned hydrocarbon emissions. Nitrogen oxide emissions and reactor pressure drop were also measured. At a reference velocity of 10 m/s, the CO and unburned hydrocarbons emissions, and, therefore, the combustion efficiency, were independent of inlet temperature. At an inlet temperature of 1000 K, they were independent of reference velocity. Nitrogen oxides emissions resulted from conversion of the small amount (135 ppm) of fuel-bound nitrogen in the fuel. Up to 90 percent conversion was observed with no apparent effect of any of the test variables. For typical gas turbine operating conditions, all three pollutants were below levels which would permit the most stringent proposed automotive emissions standards to be met.

  11. Rigid-plug elastic-water model for transient pipe flow with entrapped air pocket

    SciTech Connect

    Zhou, Ling; Liu, Prof. Deyou; Karney, Professor Byran W.; Zhang, Qin Fen; OU, CHANGQI

    2011-01-01

    Pressure transients in a rapidly filling pipe with an entrapped air pocket are investigated analytically. A rigid-plug elastic water model is developed by applying elastic water hammer to the majority of the water column while applying rigid water analysis to a small portion near the air-water interface, which avoids effectively the interpolation error of previous approaches. Moreover, another two simplified models are introduced respectively based on constant water length and by neglecting water elasticity. Verification of the three models is confirmed by experimental results. Calculations show that the simplification of constant water length is feasible for small air pockets. The complete rigid water model is appropriate for cases with large initial air volume. The rigid-plug elastic model can predict all the essential features for the entire range of initial air fraction considered in this study, and it is the effective model for analysis of pressure transients of entrapped air.

  12. Determination of air/water ratio in pipes by fast neutrons: experiment and Monte Carlo simulation.

    PubMed

    AboAlfaraj, Tareq; Abdul-Majid, Samir

    2012-04-01

    Fast neutron dose attenuation from a (252)Cf neutron source is used for the determination of air to water ratio in pipes. Such measurement of the two-phase flow volume fraction is important for many industrial plants such as desalination plants and oil refineries. Fast neutrons penetrate liquid more than slow neutrons or gamma rays. Using diameters from 11.5 cm to 20.76 cm and with wall thicknesses from 0.45 to 1.02 cm, attenuation was independent of pipe wall thicknesses and diameters. Experimental data was in good agreement with values calculated using MCNP codes. The measured neutron flux values decreased with increasing water levels in pipes up to about 14 cm, indicating that our system can be used successfully in desalination plants in pipes of different sizes. The experimental sensitivity was found to be about 0.015 mSv/hcm and the system can be used to measure water level changes down to few millimeters. Use of such a system in fixed positions in the plant can provide information on plant's overall performance and can detect loss of flow immediately before any consequences. A portable system could be designed to measure the air to water ratio in different locations in the plant in a relatively short time.

  13. Heat pipes to reduce engine exhaust emissions

    NASA Technical Reports Server (NTRS)

    Schultz, D. F. (Inventor)

    1984-01-01

    A fuel combustor is presented that consists of an elongated casing with an air inlet conduit portion at one end, and having an opposite exit end. An elongated heat pipe is mounted longitudinally in the casing and is offset from and extends alongside the combustion space. The heat pipe is in heat transmitting relationship with the air intake conduit for heating incoming air. A guide conduit structure is provided for conveying the heated air from the intake conduit into the combustion space. A fuel discharge nozzle is provided to inject fuel into the combustion space. A fuel conduit from a fuel supply source has a portion engaged in heat transfer relationship of the heat pipe for preheating the fuel. The downstream end of the heat pipe is in heat transfer relationship with the casing and is located adjacent to the downstream end of the combustion space. The offset position of the heat pipe relative to the combustion space minimizes the quenching effect of the heat pipe on the gaseous products of combustion, as well as reducing coking of the fuel on the heat pipe, thereby improving the efficiency of the combustor.

  14. An inlet air washer/chiller system for combined cycle planet repowering

    SciTech Connect

    Sengupta, U.; Soroka, G. )

    1989-01-01

    A conditioning method to achieve increased output at any relative humidity condition is an air washer and absorption chiller arrangement. At elevated temperatures and low humidity, the air washer operates as an evaporative cooler without the chiller in operation. In this mode, the air washer will give similar results as a media type evaporative cooler at a fraction of the pressure loss. In the air washer plus chiller operating mode the chiller maintains cooling effectiveness of the air washer during periods of high relative humidity. This makes such a system very appropriate anywhere relative humidity is high. Many combined cycle plants utilize supplemental firing of the heat recovery steam generators to offset the loss of gas turbine power at high ambient temperatures. This paper shows that in contrast to supplementary firing, the combination air washer/chiller system can generate power more efficiently and at lower cost.

  15. Optimal Micro-Jet Flow Control for Compact Air Vehicle Inlets

    NASA Technical Reports Server (NTRS)

    Anderson, Bernhard H.; Miller, Daniel N.; Addington, Gregory A.; Agrell, Johan

    2004-01-01

    The purpose of this study on micro-jet secondary flow control is to demonstrate the viability and economy of Response Surface Methodology (RSM) to optimally design micro-jet secondary flow control arrays, and to establish that the aeromechanical effects of engine face distortion can also be included in the design and optimization process. These statistical design concepts were used to investigate the design characteristics of "low mass" micro-jet array designs. The term "low mass" micro-jet may refers to fluidic jets with total (integrated) mass flow ratios between 0.10 and 1.0 percent of the engine face mass flow. Therefore, this report examines optimal micro-jet array designs for compact inlets through a Response Surface Methodology.

  16. 49 CFR 179.220-17 - Gauging devices, top loading and unloading devices, venting and air inlet devices.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... any other fixture and must be tightly closed. Each unloading pipe must be securely anchored within the... with operating handles removed are used. Provision must be made for closing pipe connections of valves... cover closed, a telltale pipe may be provided. The telltail pipe must be capable of determining...

  17. Integration of air separation membrane and coalescing filter for use on an inlet air system of an engine

    DOEpatents

    Moncelle, Michael E.

    2003-01-01

    An intake air separation system suitable for combustion air of an internal combustion engine. An air separation device of the system includes a plurality of fibers, each fiber having a tube with a permeation barrier layer on the outer surface thereof and a coalescing layer on the inner surface thereof, to restrict fluid droplets from contacting the permeation barrier layer.

  18. Effect of Gas/Steam Turbine Inlet Temperatures on Combined Cycle Having Air Transpiration Cooled Gas Turbine

    NASA Astrophysics Data System (ADS)

    Kumar, S.; Singh, O.

    2012-10-01

    Worldwide efforts are being made for further improving the gas/steam combined cycle performance by having better blade cooling technology in topping cycle and enhanced heat recovery in bottoming cycle. The scope of improvement is possible through turbines having higher turbine inlet temperatures (TITs) of both gas turbine and steam turbine. Literature review shows that a combined cycle with transpiration cooled gas turbine has not been analyzed with varying gas/steam TITs. In view of above the present study has been undertaken for thermodynamic study of gas/steam combined cycle with respect to variation in TIT in both topping and bottoming cycles, for air transpiration cooled gas turbine. The performance of combined cycle with dual pressure heat recovery steam generator has been evaluated for different cycle pressure ratios (CPRs) varying from 11 to 23 and the selection diagrams presented for TIT varying from 1,600 to 1,900 K. Both the cycle efficiency and specific work increase with TIT for each pressure ratio. For each TIT there exists an optimum pressure ratio for cycle efficiency and specific work. For the CPR of 23 the best cycle performance is seen at a TIT of 1,900 K for maximum steam temperature of 570 °C, which gives the cycle efficiency of 60.9 % with net specific work of 909 kJ/kg.

  19. Analytical evaluation of effect of equivalence ratio inlet-air temperature and combustion pressure on performance of several possible ram-jet fuels

    NASA Technical Reports Server (NTRS)

    Tower, Leonard K; Gammon, Benson E

    1953-01-01

    The results of an analytical investigation of the theoretical air specific impulse performance and adiabatic combustion temperatures of several possible ram-jet fuels over a range of equivalence ratios, inlet-air temperatures, and combustion pressures, is presented herein. The fuels include octane-1, 50-percent-magnesium slurry, boron, pentaborane, diborane, hydrogen, carbon, and aluminum. Thermal effects from high combustion temperatures were found to effect considerably the combustion performance of all the fuels. An increase in combustion pressure was beneficial to air specific impulse at high combustion temperatures. The use of these theoretical data in engine operation and in the evaluation of experimental data is described.

  20. Investigation at supersonic and subsonic Mach numbers of auxiliary inlets supplying secondary air flow to ejector exhaust nozzles

    NASA Technical Reports Server (NTRS)

    Hearth, Donald P; Cubbison, Robert W

    1956-01-01

    The results indicated increases in auxiliary-inlet pressure recovery with increases in scoop height relative to the boundary-layer thickness. The pressure recovery increased at about the same rate as theoretically predicted for an inlet in a boundary layer having a one-seventh power profile, but was only about 0.68 to 0.75 of the theoretically obtainable values. Under some operating conditions, flow from the primary jet was exhausted through the auxiliary inlet. This phenomenon could be predicted from the ejector pumping characteristics.

  1. The effect of different inlet conditions of air in a rectangular channel on convection heat transfer: Turbulence flow

    SciTech Connect

    Kurtbas, Irfan

    2008-10-15

    Theoretical and empirical correlations for duct flow are given for hydrodynamically and thermally developed flow in most of previous studies. However, this is commonly not a realistic inlet configuration for heat exchanger, in which coolant flow generally turns through a serpentine shaped passage before entering heat sinks. Accordingly, an experimental investigation was carried out to determine average heat transfer coefficients in uniformly heated rectangular channel with 45 and 90 turned flow, and with wall mounted a baffle. The channel was heated through bottom side with the baffle. In present work, a detailed study was conducted for three different height of entry channel (named as the ratio of the height of entry channel to the height of test section (anti H{sub c}=h{sub c}/H)) by varying Reynolds number (Re{sub Dh}). Another variable parameter was the ratio of the baffle height to the channel height (anti H{sub b}=h{sub b}/H). Only one baffle was attached on the bottom (heating) surface. The experimental procedure was validated by comparing the data for the straight channel with no baffle. Reynolds number (Re{sub Dh}) was varied from 2800 to 30,000, so the flow was considered as only turbulent regime. All experiments were conduced with air accordingly; Prandtl number (Pr) was approximately fixed at 0.71. The results showed that average Nusselt number for {theta}=45 and {theta}=90 were 9% and 30% higher, respectively, than that of the straight channel without baffle. Likewise, the pressure drop increased up to 4.4 to 5.3 times compare to the straight channel. (author)

  2. Modelling Air and Water Two-Phase Annular Flow in a Small Horizontal Pipe

    NASA Astrophysics Data System (ADS)

    Yao, Jun; Yao, Yufeng; Arini, Antonino; McIiwain, Stuart; Gordon, Timothy

    2016-06-01

    Numerical simulation using computational fluid dynamics (CFD) has been carried out to study air and water two-phase flow in a small horizontal pipe of an inner diameter of 8.8mm, in order to investigate unsteady flow pattern transition behaviours and underlying physical mechanisms. The surface liquid film thickness distributions, determined by either wavy or full annular flow regime, are shown in reasonable good agreement with available experimental data. It was demonstrated that CFD simulation was able to predict wavy flow structures accurately using two-phase flow sub-models embedded in ANSYS-Fluent solver of Eulerian-Eulerian framework, together with a user defined function subroutine ANWAVER-UDF. The flow transient behaviours from bubbly to annular flow patterns and the liquid film distributions revealed the presence of gas/liquid interferences between air and water film interface. An increase of upper wall liquid film thickness along the pipe was observed for both wavy annular and full annular scenarios. It was found that the liquid wavy front can be further broken down to form the water moisture with liquid droplets penetrating upwards. There are discrepancies between CFD predictions and experimental data on the liquid film thickness determined at the bottom and the upper wall surfaces, and the obtained modelling information can be used to assist further 3D user defined function subroutine development, especially when CFD simulation becomes much more expense to model full 3D two-phase flow transient performance from a wavy annular to a fully developed annular type.

  3. Attic inlet technology

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Rising fuel costs have driven development of alternative heat sources for poultry growers. Attic inlets are employed to pre-heat incoming ventilation air to reduce fuel usage. Attic temperatures are at least 10 °F warmer than the outside temperature at least 80% of the time and offers a source of...

  4. Effects of Inlet Icing on Performance of Axial-flow Turbojet Engine in Natural Icing Conditions

    NASA Technical Reports Server (NTRS)

    Acker, Loren W; Kleinknecht, Kenneth S

    1950-01-01

    A flight investigation in natural icing conditions was conducted to determine the effect of inlet ice formations on the performance of axial-flow turbojet engines. The results are presented for icing conditions ranging from a liquid-water content of 0.1 to 0.9 gram per cubic meter and water-droplet size from 10 to 27 microns at ambient-air temperature from 13 to 26 degrees F. The data show time histories of jet thrust, air flow, tail-pipe temperature, compressor efficiency, and icing parameters for each icing encounter. The effect of inlet-guide-vane icing was isolated and shown to account for approximately one-half the total reduction in performance caused by inlet icing.

  5. Study on measurement of the coal powder concentration in pneumatic pipes of a boiler with relationship between air velocity and pressure drop

    SciTech Connect

    Pan, W.; Shen, F.; Lin, W.; Chen, L.; Zhang, D.; Wang, Q.; Ke, J.; Quan, W.

    1999-07-01

    According to the theoretical relationship between air velocity and pressure drop in different solid-air mass flow in vertical pipes with the condition of upward air-solid flowing, the experimental research on measuring the coal powder concentration is directed against the pneumatic pipes of a boiler's combustion system in the energy industry. Through analyzing the experimental results, a mathematical model for measuring the coal powder concentration in pneumatic pipes is obtained. Then, the error analysis is done, and the method of on-line measurement and its function are provided.

  6. Repair of Corrosion in Air Supply Piping at the NASA Glenn Research Center's 1 by 1 Foot Supersonic Wind Tunnel

    NASA Technical Reports Server (NTRS)

    Henry, Michael

    2000-01-01

    During a test at the NASA Glenn Research Center's 1 x 1 Supersonic Wing Tunnel, it was discovered that particles entrained in the air flow were damaging the pressure sensitive paint on a test article. An investigation found the source of the entrained particles to be rust on the internal surfaces of the air supply piping. To remedy the situation, the air supply line components made from carbon steel were either refurbished or replaced with new stainless steel components. The refurbishment process included various combinations of chemical cleaning, bead blasting, painting and plating.

  7. 65. FIRE SUPPRESSION PIPES BEHIND FLAME BUCKET. PIPES TO UMBILICAL ...

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

    65. FIRE SUPPRESSION PIPES BEHIND FLAME BUCKET. PIPES TO UMBILICAL MAST IN LOWER LEFT CORNER; PIPES TO LAUNCHER IN UPPER LEFT CORNER; PIPES TO FLAME BUCKET IN LOWER RIGHT CORNER OF PHOTOGRAPH. POTABLE WATER PIPING IN UPPER RIGHT CORNER OF PHOTO. - Vandenberg Air Force Base, Space Launch Complex 3, Launch Pad 3 East, Napa & Alden Roads, Lompoc, Santa Barbara County, CA

  8. Experimental Investigation of an Air-Cooled Turbine Operating in a Turbojet Engine at Turbine Inlet Temperatures up to 2500 F

    NASA Technical Reports Server (NTRS)

    Cochran, Reeves P.; Dengler, Robert P.

    1961-01-01

    An experimental investigation was made of an air-cooled turbine at average turbine inlet temperatures up to 2500 F. A modified production-model 12-stage axial-flow-compressor turbojet engine operating in a static sea-level stand was used as the test vehicle. The modifications to the engine consisted of the substitution of special combustor and turbine assemblies and double-walled exhaust ducting for the standard parts of the engine. All of these special parts were air-cooled to withstand the high operating temperatures of the investigation. The air-cooled turbine stator and rotor blades were of the corrugated-insert type. Leading-edge tip caps were installed on the rotor blades to improve leading-edge cooling by diverting the discharge of coolant to regions of lower gas pressure toward the trailing edge of the blade tip. Caps varying in length from 0.15- to 0.55-chord length were used in an attempt to determine the optimum cap length for this blade. The engine was operated over a range of average turbine inlet temperatures from about 1600 to about 2500 F, and a range of average coolant-flow ratios of 0.012 to 0.065. Temperatures of the air-cooled turbine rotor blades were measured at all test conditions by the use of thermocouples and temperature-indicating paints. The results of the investigation indicated that this type of blade is feasible for operation in turbojet engines at the average turbine inlet temperatures and stress levels tested(maximums of 2500 F and 24,000 psi, respectively). An average one-third-span blade temperature of 1300 F could be maintained on 0.35-chord tip cap blades with an average coolant-flow ratio of about 0.022 when the average turbine inlet temperature was 2500 F and cooling-air temperature was about 260 F. All of the leading-edge tip cap lengths improved the cooling of the leading-edge region of the blades, particularly at low average coolant-flow ratios. At high gas temperatures, such parts as the turbine stator and the combustor

  9. Illustrations and supporting texts for sound standing waves of air columns in pipes in introductory physics textbooks

    NASA Astrophysics Data System (ADS)

    Zeng, Liang; Smith, Chris; Poelzer, G. Herold; Rodriguez, Jennifer; Corpuz, Edgar; Yanev, George

    2014-12-01

    In our pilot studies, we found that many introductory physics textbook illustrations with supporting text for sound standing waves of air columns in open-open, open-closed, and closed-closed pipes inhibit student understanding of sound standing wave phenomena due to student misunderstanding of how air molecules move within these pipes. Based on the construct of meaningful learning from cognitive psychology and semiotics, a quasiexperimental study was conducted to investigate the comparative effectiveness of two alternative approaches to student understanding: a traditional textbook illustration approach versus a newly designed air molecule motion illustration approach. Thirty volunteer students from introductory physics classes were randomly assigned to two groups of 15 each. Both groups were administered a presurvey. Then, group A read the air molecule motion illustration handout, and group B read a traditional textbook illustration handout; both groups were administered postsurveys. Subsequently, the procedure was reversed: group B read the air molecule motion illustration handout and group A read the traditional textbook illustration handout. This was followed by a second postsurvey along with an exit research questionnaire. The study found that the majority of students experienced meaningful learning and stated that they understood sound standing wave phenomena significantly better using the air molecule motion illustration approach. This finding provides a method for physics education researchers to design illustrations for abstract sound standing wave concepts, for publishers to improve their illustrations with supporting text, and for instructors to facilitate deeper learning in their students on sound standing waves.

  10. Inlet/Body Integration Preliminary Design for Supersonic Air-Breathing Missiles Using Automated Multi-Discilinary Optimization

    DTIC Science & Technology

    2000-06-01

    configuration, 33 ometry necessitate sophisticated numerical codes rameters to be d fine theigura tio and refined spatial discretizations which are...get there. The development strategy the exit location of the inlet subsonic diffuser is followed by Aerospatiale Matra Missiles and Rut- fixed. Second...approxi- Parameter Name Value mate 2- D /3- D geometrical models and low accu- 1 Missile diameter (caliber) 1 D racy physical analysis models. 2 Base diameter

  11. PIPING FOR COOLANT WATER IS INSTALLED INSIDE REACTOR STRUCTURE PRIOR ...

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

    PIPING FOR COOLANT WATER IS INSTALLED INSIDE REACTOR STRUCTURE PRIOR TO EMBEDMENT IN CONCRETE. HIGHER PIPE IS INLET; THE OTHER, THE OUTLET LOOP. INLET PIPE WILL CONNECT TO TOP SECTION OF REACTOR VESSEL. INL NEGATIVE NO. 1287. Unknown Photographer, 1/18/1951 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

  12. Effect of suction pipe leaning angle and water level on the internal flow of pump sump

    NASA Astrophysics Data System (ADS)

    Chen, Z.-M.; Lee, Y.-B.; Kim, K.-Y.; Park, S.-H.; Choi, Y.-D.

    2016-11-01

    The pump sump, which connects forebay and intake of pump station, supplies good flow condition for the intake of the pump. If suction sumps are improperly shaped or sized, air entraining vortices or submerged vortices may develop. This may greatly affect pump operation if vortices grow to an appreciable extent. Moreover, the noise and vibration of the pump can be increased by the remaining of vortices in the pump flow passage. Therefore, the vortices in the pump flow passage have to be reduced for a good performance of pump sump station. In this study, the effect of suction pipe leaning angle on the pump sump internal flow with different water level has been investigated by CFD analysis. Moreover, an elbow type pipe was also investigated. There are 3 leaning angles with 0°, 45° and 90° for the suction pipe. The suction pipe inlet centre is kept same for all the cases. In addition, the three different water levels of H/D=1.85, 1.54, and 1.31, is applied to different suction pipe types. The result shows that the amount of air sucked into the suction pipe increases with increasing the suction pipe leaning angle. Especially for the horizontal suction pipe, there is maximum air sucked into the suction pipe. However, there is certain effect of the elbow type bell mouth installation in the horizontal suction pipe on suppressing the amount of air sucked into the pipe. Moreover, vertical suction pipe plays an effective role on reducing the free surface vortex intake area.

  13. Two-dimensional symmetrical inlets with external compression

    NASA Technical Reports Server (NTRS)

    Ruden, P

    1950-01-01

    The purpose of inlets like, for instance, those of air-cooled radiators and scoops is to take a certain air quantity out of the free stream and to partly convert the free-stream velocity into pressure. In the extreme case this pressure conversion may occur either entirely in the interior of the inlet (inlet with internal compression) or entirely in the free stream ahead of the inlet (inlet with external compression). In this report a theory for two-dimensional inlets with external compression is developed and illustrated by numerical examples. Intermediary forms between inlets with internal and external compression which can be derived from the latter are briefly discussed.

  14. A Computational and Experimental Study of Coflow Laminar Methane/Air Diffusion Flames: Effects of Fuel Dilution, Inlet Velocity, and Gravity

    NASA Technical Reports Server (NTRS)

    Cao, S.; Ma, B.; Bennett, B. A. V.; Giassi, D.; Stocker, D. P.; Takahashi, F.; Long, M. B.; Smooke, M. D.

    2014-01-01

    The influences of fuel dilution, inlet velocity, and gravity on the shape and structure of laminar coflow CH4-air diffusion flames were investigated computationally and experimentally. A series of nitrogen-diluted flames measured in the Structure and Liftoff in Combustion Experiment (SLICE) on board the International Space Station was assessed numerically under microgravity (mu g) and normal gravity (1g) conditions with CH4 mole fraction ranging from 0.4 to 1.0 and average inlet velocity ranging from 23 to 90 cm/s. Computationally, the MC-Smooth vorticity-velocity formulation was employed to describe the reactive gaseous mixture, and soot evolution was modeled by sectional aerosol equations. The governing equations and boundary conditions were discretized on a two-dimensional computational domain by finite differences, and the resulting set of fully coupled, strongly nonlinear equations was solved simultaneously at all points using a damped, modified Newton's method. Experimentally, flame shape and soot temperature were determined by flame emission images recorded by a digital color camera. Very good agreement between computation and measurement was obtained, and the conclusions were as follows. (1) Buoyant and nonbuoyant luminous flame lengths are proportional to the mass flow rate of the fuel mixture; computed and measured nonbuoyant flames are noticeably longer than their 1g counterparts; the effect of fuel dilution on flame shape (i.e., flame length and flame radius) is negligible when the flame shape is normalized by the methane flow rate. (2) Buoyancy-induced reduction of the flame radius through radially inward convection near the flame front is demonstrated. (3) Buoyant and nonbuoyant flame structure is mainly controlled by the fuel mass flow rate, and the effects from fuel dilution and inlet velocity are secondary.

  15. Investigation of High-Subsonic Performance Characteristics of a 12 Degree 21-Inch Conical Diffuser, Including the Effects of Change in Inlet-Boundary-Layer Thickness

    NASA Technical Reports Server (NTRS)

    Copp, Martin R.; Klevatt, Paul L.

    1950-01-01

    Investigations were conducted of a 12 degree 21-inch conical diffuser of 2:l area ratio to determine the interrelation of boundary layer growth and performance characteristics. surveys were made of inlet and exit from, longitudinal static pressures were recorded, and velocity profiles were obtained through an inlet Reynolds number range, determined From mass flows and based on inlet diameter of 1.45 x 10(exp 6) to 7.45 x 10(exp 6) and a Mach number range of 0.11 to approximately choking. These investigations were made to two thicknesses of inlet boundary layer. The mean value, over the entire range of inlet velocities, of the displacement thickness of the thinner inlet boundary layer was approximately 0.035 inch and that of the thicker inlet boundary layer was approximately six times this value. The loss coefficient in the case of the thinner inlet boundary layer had a value between 2 to 3 percent of the inlet impact pressure over most of the air-flow range. The loss coefficient with the thicker inlet boundary layer was of the order of twice that of the thinner inlet boundary layer at low speeds and approximately three times at high speeds. In both cases the values were substantially less than those given in the literature for fully developed pipe flow. The static-pressure rise for the thinner inlet boundary layer was of the order of 95 percent of that theoretically possible over the entire speed range. For the thicker inlet boundary layer the static pressure rise, as a percentage of that theoretically possible, ranged from 82 percent at low speeds to 68 percent at high speeds.

  16. Solar assist and filter construction for dryer inlet

    SciTech Connect

    Commander, B.C.

    1981-07-21

    An air inlet construction for a domestic clothes dryer is described including a pair of selectively usable air inlet ports. One of the air inlet ports opens outwardly to the area immediately adjacent and exterior of the dryer and the other inlet port opens into the interior of a non-domestically heated portion of the building in which the dryer is disposed, but which portion is subject to being heated by solar energy during the daylight hours.

  17. Energy savings in one-pipe steam heating systems fitted with high-capacity air vents. Final report

    SciTech Connect

    Not Available

    1994-09-01

    Multifamily buildings heated by one-pipe steam systems experience significant temperature gradients from apartment to apartment, often reaching 15{degrees}F. As a result, many tenants are to cold, or if the heating system output is increased so as to heat the coldest apartment adequately, too hot. While both are undesirable, the second is particularly so because it wastes energy. It was thought that insufficient air venting of the steam pipes contributed to the gradient. Theoretically, if steam mains and risers are quickly vented, steam will reach each radiator at approximately the same time and balance apartment temperatures. The project`s objective was to determine if the installation of large-capacity air vents at the ends of steam mains and risers would economically reduce the temperature gradient between apartments and reduce the amount of space heating energy required. The test was conducted by enabling and disabling air vents biweekly in 10 multifamily buildings in New York City between December 1992 to May 1993. The temperatures of selected apartments and total space heating energy were compared during each venting regime. There was no difference in energy consumption between ``vents on`` and ``vents off`` periods (see Tables 2 and 5); however, there was a reduction in the maximum spread of apartment temperatures.

  18. CFD Analysis to Study Effect of Circular Vortex Generator Placed in Inlet Section to Investigate Heat Transfer Aspects of Solar Air Heater

    PubMed Central

    Gawande, Vipin B.; Dhoble, A. S.; Zodpe, D. B.

    2014-01-01

    CFD analysis of 2-dimensional artificially roughened solar air heater duct with additional circular vortex generator, inserted in inlet section is carried out. Circular transverse ribs on the absorber plate are placed as usual. The analysis is done to investigate the effect of inserting additional vortex generator on the heat transfer and flow friction characteristics inside the solar air heater duct. This investigation covers relative roughness pitch in the range of 10 ≤ P/e ≤ 25 and relevant Reynolds numbers in the range of 3800 ≤ Re ≤ 18000. Relative roughness height (e/D) is kept constant as 0.03 for analysis. The turbulence created due to additional circular vortex generator increases the heat transfer rate and at the same time there is also increase in friction factor values. For combined arrangement of ribs and vortex generator, maximum Nusselt number is found to be 2.05 times that of the smooth duct. The enhancement in Nusselt number with ribs and additional vortex generator is found to be 1.06 times that of duct using ribs alone. The maximum increase in friction factor with ribs and circular vortex generator is found to be 2.91 times that of the smooth duct. Friction factor in a combined arrangement is 1.114 times that in a duct with ribs alone on the absorber plate. The augmentation in Thermal Enhancement Factor (TEF) with vortex generator in inlet section is found to be 1.06 times more than with circular ribs alone on the absorber plate. PMID:25254251

  19. CFD analysis to study effect of circular vortex generator placed in inlet section to investigate heat transfer aspects of solar air heater.

    PubMed

    Gawande, Vipin B; Dhoble, A S; Zodpe, D B

    2014-01-01

    CFD analysis of 2-dimensional artificially roughened solar air heater duct with additional circular vortex generator, inserted in inlet section is carried out. Circular transverse ribs on the absorber plate are placed as usual. The analysis is done to investigate the effect of inserting additional vortex generator on the heat transfer and flow friction characteristics inside the solar air heater duct. This investigation covers relative roughness pitch in the range of 10 ≤ P/e ≤ 25 and relevant Reynolds numbers in the range of 3800 ≤ Re ≤ 18000. Relative roughness height (e/D) is kept constant as 0.03 for analysis. The turbulence created due to additional circular vortex generator increases the heat transfer rate and at the same time there is also increase in friction factor values. For combined arrangement of ribs and vortex generator, maximum Nusselt number is found to be 2.05 times that of the smooth duct. The enhancement in Nusselt number with ribs and additional vortex generator is found to be 1.06 times that of duct using ribs alone. The maximum increase in friction factor with ribs and circular vortex generator is found to be 2.91 times that of the smooth duct. Friction factor in a combined arrangement is 1.114 times that in a duct with ribs alone on the absorber plate. The augmentation in Thermal Enhancement Factor (TEF) with vortex generator in inlet section is found to be 1.06 times more than with circular ribs alone on the absorber plate.

  20. Wind tunnel tests of a zero length, slotted-lip engine air inlet for a fixed nacelle V/STOL aircraft

    NASA Technical Reports Server (NTRS)

    Woollett, R. R.; Beck, W. E., Jr.; Glasgow, E. R.

    1982-01-01

    Zero length, slotted lip inlet performance and associated fan blade stresses were determined during model tests using a 20 inch diameter fan simulator in the NASA-LeRC 9 by 15 foot low speed wind tunnel. The model configuration variables consisted of inlet contraction ratio, slot width, circumferential extent of slot fillers, and length of a constant area section between the inlet throat and fan face. The inlet performance was dependent on slot gap width and relatively independent of inlet throat/fan face spacer length and slot flow blockage created by 90 degree slot fillers. Optimum performance was obtained at a slot gap width of 0.36 inch. The zero length, slotted lip inlet satisfied all critical low speed inlet operating requirements for fixed horizontal nacelles subsonic V/STOL aircraft.

  1. Heat Pipes

    NASA Technical Reports Server (NTRS)

    1990-01-01

    Bobs Candies, Inc. produces some 24 million pounds of candy a year, much of it 'Christmas candy.' To meet Christmas demand, it must produce year-round. Thousands of cases of candy must be stored a good part of the year in two huge warehouses. The candy is very sensitive to temperature. The warehouses must be maintained at temperatures of 78-80 degrees Fahrenheit with relative humidities of 38- 42 percent. Such precise climate control of enormous buildings can be very expensive. In 1985, energy costs for the single warehouse ran to more than $57,000 for the year. NASA and the Florida Solar Energy Center (FSEC) were adapting heat pipe technology to control humidity in building environments. The heat pipes handle the jobs of precooling and reheating without using energy. The company contacted a FSEC systems engineer and from that contact eventually emerged a cooperative test project to install a heat pipe system at Bobs' warehouses, operate it for a period of time to determine accurately the cost benefits, and gather data applicable to development of future heat pipe systems. Installation was completed in mid-1987 and data collection is still in progress. In 1989, total energy cost for two warehouses, with the heat pipes complementing the air conditioning system was $28,706, and that figures out to a cost reduction.

  2. Heat Pipes

    NASA Astrophysics Data System (ADS)

    1990-01-01

    Bobs Candies, Inc. produces some 24 million pounds of candy a year, much of it 'Christmas candy.' To meet Christmas demand, it must produce year-round. Thousands of cases of candy must be stored a good part of the year in two huge warehouses. The candy is very sensitive to temperature. The warehouses must be maintained at temperatures of 78-80 degrees Fahrenheit with relative humidities of 38- 42 percent. Such precise climate control of enormous buildings can be very expensive. In 1985, energy costs for the single warehouse ran to more than 57,000 for the year. NASA and the Florida Solar Energy Center (FSEC) were adapting heat pipe technology to control humidity in building environments. The heat pipes handle the jobs of precooling and reheating without using energy. The company contacted a FSEC systems engineer and from that contact eventually emerged a cooperative test project to install a heat pipe system at Bobs' warehouses, operate it for a period of time to determine accurately the cost benefits, and gather data applicable to development of future heat pipe systems. Installation was completed in mid-1987 and data collection is still in progress. In 1989, total energy cost for two warehouses, with the heat pipes complementing the air conditioning system was 28,706, and that figures out to a cost reduction.

  3. 49 CFR 179.200-16 - Gauging devices, top loading and unloading devices, venting and air inlet devices.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Gauging devices, top loading and unloading devices... DOT-111AW and 115AW) § 179.200-16 Gauging devices, top loading and unloading devices, venting and air...). In no case shall the wall thickness be less than that specified in § 179.201-1. (f) When top...

  4. Experimental Investigation of Thermal Performance of Miniature Heat Pipe Using SiO2-Water Nanofluids.

    PubMed

    Niu, Yan-Fang; Zhao, Wei-Lin; Gong, Yu-Ying

    2015-04-01

    The four miniature heat pipes filled with DI water and SiO2-water nanofluids containing different volume concentrations (0.2%, 0.6% and 1.0%) are experimentally measured on the condition of air and water cooling. The wall temperature and the thermal resistance are investigated for three inclination angles. At the same of inlet heat water temperature in the heat system, it is observed that the total wall temperatures on the evaporator section are almost retaining constant by air cooling and the wall temperatures at the front end of the evaporator section are slightly reduced by water cooling. However, the wall temperatures at the condenser section using SiO2-water nanofluids are all higher than that for DI water on the two cooling conditions. As compared with the heat pipe using DI water, the decreasing of the thermal resistance in heat pipe using nanofluids is about 43.10%-74.46% by air cooling and 51.43%-72.22% by water cooling. These indicate that the utilization of SiO2-water nanofluids as working fluids enhances the performance of the miniature heat pipe. When the four miniature heat pipes are cut to examine at the end of the experiment, a thin coating on the surface of the screen mesh of the heat pipe using SiO2-water nanofluids is found. This may be one reason for reinforcing the heat transfer performance of the miniature heat pipe.

  5. Dynamics of the inlet system of a four-stroke engine

    NASA Technical Reports Server (NTRS)

    Boden, R H; Schecter, Harry

    1944-01-01

    Tests were run on a single-cylinder and a multicylinder four-stroke engine in order to determine the effect of the dynamics of the inlet system upon indicated mean effective pressure. Tests on the single-cylinder engine were made at various speeds, inlet valve timings, and inlet pipe lengths. These tests indicated that the indicated mean effective pressure could be raised considerably at any one speed by the use of a suitably long inlet pipe. Tests at other speeds with this length of pipe showed higher indicated mean effective pressure than with a very short pipe, although not so high as could be obtained with the pipe length adjusted for each speed. A general relation was discovered between optimum time of inlet valve closing and pipe length; namely, that longer pipes require later inlet valve closing in order to be fully effective. Tests were also made on three cylinders connected to a single pipe. With this arrangement, increased volumetric efficiency at low speed was obtainable by using a long pipe, but only with a sacrifice of volumetric efficiency at high speed. Volumetric efficiency at high speed was progressively lower as the pipe length was increased.

  6. Inlet Geomorphology Evolution

    DTIC Science & Technology

    2015-04-01

    APR 2015 2. REPORT TYPE 3. DATES COVERED 00-00-2015 to 00-00-2015 4. TITLE AND SUBTITLE Inlet Geomorphology Evolution 5a. CONTRACT NUMBER 5b...Std Z39-18 Coastal Inlets Research Program Inlet Geomorphology Evolution The Inlet Geomorphology Evolution work unit of the CIRP evaluates

  7. Inlet Engineering Toolbox

    DTIC Science & Technology

    2014-10-31

    ADDRESS(ES) U.S. Army Engineer Research and Development Center,CIRP - The Coastal Inlets Research Program,3909 Halls Ferry Road,Vicksburg,MS,39180... Coastal Inlets Research Program Inlet Engineering Toolbox The Inlet Engineering Toolbox (IET) Work Unit develops desktop PC and web-based tools to...aid in studies of the consequences of engineering actions at coastal inlets and adjacent beaches. District scientists and engineers need rapid

  8. Give Earth a Chance Series, Dirty Air, Trash Is Taking Over, Sounds and Silence, Pesticides Are Perilous, Tragedy in the Laundromat, Troublesome Tail Pipes.

    ERIC Educational Resources Information Center

    Minneapolis Independent School District 275, Minn.

    These six booklets in the "Give Earth a Chance Series" are titled, "Dirty Air,""Trash is Taking Over,""Sounds and Silence,""Pesticides are Perilous,""Tragedy in the Laundromat," and "Troublesome Tail Pipes." The booklets are suitable for elementary use, and are intended to…

  9. Theoretical and experimental validation study on automotive air-conditioning based on heat pipe and LNG cold energy for LNG-fueled heavy vehicles

    NASA Astrophysics Data System (ADS)

    Deng, Dong; Cheng, Jiang-ping; Zhang, Sheng-chang; Ge, Fang-gen

    2017-03-01

    As a clean fuel, LNG has been used in heavy vehicles widely in China. Before reaching the engine for combustion, LNG store in a high vacuum multi-layer thermal insulation tank and need to be evaporated from its cryogenic state to natural gas. During the evaporation, the available cold energy of LNG has been calculated. The concept has been proposed that the separated type heat pipe technology is employed to utilize the available cold energy for automotive air-conditioning. The experiment has been conducted to validate the proposal. It is found that it is feasible to use the separated type heat pipe to convey the cold energy from LNG to automotive air-conditioning. And the cooling capacity of the automotive air-conditioning increase with the LNG consumption and air flow rate increasing.

  10. Homemade Firearm Suicide With Dumbbell Pipe Triggering by an Air-Compressed Gun: Case Report and Review of Literature.

    PubMed

    Le Garff, Erwan; Delannoy, Yann; Mesli, Vadim; Berthezene, Jean Marie; Morbidelli, Philippe; Hédouin, Valéry

    2015-12-01

    Firearm suicides are frequent and well described in the forensic literature, particularly in Europe and the United States. However, the use of homemade and improvised firearms is less well described. The present case reports a suicide with an original improvised gun created using an air-compressed pellet gun and a dumbbell pipe. The aims of this study were to describe the scene, the external examination of the corpse, the body scan, and the autopsy; to understand the mechanism of death; and to compare the results with a review of the forensic literature to highlight the epidemiology of homemade firearm use, the tools used for homemade and improvised firearms in suicides versus homicides, and the manners in which homemade firearms are used (homicide or suicide, particularly in complex suicide cases).

  11. Cold start fuel/air mixture supply device for spark ignition internal combustion engines

    SciTech Connect

    Ross, G.E.D.

    1984-06-05

    A combined accelerator pump and cold start fuel/air mixture supply device has an automatic throttle valve in a mixture supply passage, a fuel control valve controlling flow of fuel drawn into the passage through an inlet upstream of the throttle valve, and an air valve upstream of the fuel inlet. A primary spring tends to seat the air valve. A light, secondary spring urges a plunger against the air valve to augment the load of the primary spring for a predetermined time interval after the engine begins to run under its own power. A valve in a pipe opens automatically at the end of the predetermined time interval to apply engine inlet manifold depression to the end of the plunger remote from the air valve and thereby to separate the plunger from the air valve so that only the primary spring acts on the air valve.

  12. Heat pipe cooling for scramjet engines

    NASA Technical Reports Server (NTRS)

    Silverstein, Calvin C.

    1986-01-01

    Liquid metal heat pipe cooling systems have been investigated for the combustor liner and engine inlet leading edges of scramjet engines for a missile application. The combustor liner is cooled by a lithium-TZM molybdenum annular heat pipe, which incorporates a separate lithium reservoir. Heat is initially absorbed by the sensible thermal capacity of the heat pipe and liner, and subsequently by the vaporization and discharge of lithium to the atmosphere. The combustor liner temperature is maintained at 3400 F or less during steady-state cruise. The engine inlet leading edge is fabricated as a sodium-superalloy heat pipe. Cooling is accomplished by radiation of heat from the aft surface of the leading edge to the atmosphere. The leading edge temperature is limited to 1700 F or less. It is concluded that heat pipe cooling is a viable method for limiting scramjet combustor liner and engine inlet temperatures to levels at which structural integrity is greatly enhanced.

  13. Coastal Inlets Research Program

    DTIC Science & Technology

    2015-02-09

    FEB 2015 2. REPORT TYPE 3. DATES COVERED 00-00-2015 to 00-00-2015 4. TITLE AND SUBTITLE Coastal Inlets Research Program 5a. CONTRACT NUMBER...S) AND ADDRESS(ES) U.S. Army Engineer Research and Development Center,CIRP - The Coastal Inlets Research Program,3909 Halls Ferry Road,Vicksburg,MS...CIRP.aspx Coastal Inlets Research Program The Coastal Inlets Research Program (CIRP) is a R&D Program funded through the Operations & Maintenance

  14. Extendable pipe crawler

    DOEpatents

    Hapstack, M.

    1991-05-28

    A pipe crawler is described having a front leg assembly and a back leg assembly connected together by two air cylinders, each leg assembly having four extendable legs and a pair of actuators for sliding the extendable legs radially outward to increase the range of the legs when the pipe crawler enters a section of a pipe having a larger diameter. The crawler crawls by inchworm'-like motion, the front leg assembly and back leg assembly alternately engaging and disengaging the wall of the pipe to hold the pipe crawler as the air cylinders alternately advance the front leg assembly and bring up the rear leg assembly. The pair of actuators of each leg assembly are parallel, adjacent and opposing acting so that each slides two adjacent extendable legs radially outward. 5 figures.

  15. Performance enhancement of an experimental air conditioning system by using TiO2/methanol nanofluid in heat pipe heat exchangers

    NASA Astrophysics Data System (ADS)

    Monirimanesh, Negin; Nowee, S. Mostafa; Khayyami, Shideh; Abrishamchi, Iman

    2016-05-01

    The effect of using nanofluid in thermosyphon-type heat pipe heat exchangers on energy conservation of an air-conditioning system was sought in this study. Innovatively, two heat exchangers in-series were deployed using TiO2/methanol nanofluids with 0-4 wt% concentrations as working fluids. The impacts of temperature and relative humidity on the effectiveness of 2 and 4-row heat exchangers were analyzed experimentally and more that 40 % energy saving was obtained.

  16. Prometheus Hot Leg Piping Concept

    NASA Astrophysics Data System (ADS)

    Gribik, Anastasia M.; DiLorenzo, Peter A.

    2007-01-01

    The Naval Reactors Prime Contractor Team (NRPCT) recommended the development of a gas cooled reactor directly coupled to a Brayton energy conversion system as the Space Nuclear Power Plant (SNPP) for NASA's Project Prometheus. The section of piping between the reactor outlet and turbine inlet, designated as the hot leg piping, required unique design features to allow the use of a nickel superalloy rather than a refractory metal as the pressure boundary. The NRPCT evaluated a variety of hot leg piping concepts for performance relative to SNPP system parameters, manufacturability, material considerations, and comparison to past high temperature gas reactor (HTGR) practice. Manufacturability challenges and the impact of pressure drop and turbine entrance temperature reduction on cycle efficiency were discriminators between the piping concepts. This paper summarizes the NRPCT hot leg piping evaluation, presents the concept recommended, and summarizes developmental issues for the recommended concept.

  17. Promethus Hot Leg Piping Concept

    SciTech Connect

    AM Girbik; PA Dilorenzo

    2006-01-24

    The Naval Reactors Prime Contractor Team (NRPCT) recommended the development of a gas cooled reactor directly coupled to a Brayton energy conversion system as the Space Nuclear Power Plant (SNPP) for NASA's Project Prometheus. The section of piping between the reactor outlet and turbine inlet, designated as the hot leg piping, required unique design features to allow the use of a nickel superalloy rather than a refractory metal as the pressure boundary. The NRPCT evaluated a variety of hot leg piping concepts for performance relative to SNPP system parameters, manufacturability, material considerations, and comparison to past high temperature gas reactor (HTGR) practice. Manufacturability challenges and the impact of pressure drop and turbine entrance temperature reduction on cycle efficiency were discriminators between the piping concepts. This paper summarizes the NRPCT hot leg piping evaluation, presents the concept recommended, and summarizes developmental issues for the recommended concept.

  18. Prometheus Hot Leg Piping Concept

    SciTech Connect

    Gribik, Anastasia M.; DiLorenzo, Peter A.

    2007-01-30

    The Naval Reactors Prime Contractor Team (NRPCT) recommended the development of a gas cooled reactor directly coupled to a Brayton energy conversion system as the Space Nuclear Power Plant (SNPP) for NASA's Project Prometheus. The section of piping between the reactor outlet and turbine inlet, designated as the hot leg piping, required unique design features to allow the use of a nickel superalloy rather than a refractory metal as the pressure boundary. The NRPCT evaluated a variety of hot leg piping concepts for performance relative to SNPP system parameters, manufacturability, material considerations, and comparison to past high temperature gas reactor (HTGR) practice. Manufacturability challenges and the impact of pressure drop and turbine entrance temperature reduction on cycle efficiency were discriminators between the piping concepts. This paper summarizes the NRPCT hot leg piping evaluation, presents the concept recommended, and summarizes developmental issues for the recommended concept.

  19. 49 CFR 192.319 - Installation of pipe in a ditch.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... pipe coating from equipment or from the backfill material. (c) All offshore pipe in water at least 12..., except pipe in the Gulf of Mexico and its inlets under 15 feet (4.6 meters) of water, must be installed... 49 Transportation 3 2013-10-01 2013-10-01 false Installation of pipe in a ditch. 192.319...

  20. 49 CFR 192.319 - Installation of pipe in a ditch.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... pipe coating from equipment or from the backfill material. (c) All offshore pipe in water at least 12..., except pipe in the Gulf of Mexico and its inlets under 15 feet (4.6 meters) of water, must be installed... 49 Transportation 3 2011-10-01 2011-10-01 false Installation of pipe in a ditch. 192.319...

  1. Altitude-wind-tunnel investigation of tail-pipe burning with a Westinghouse X24C-4B axial-flow turbojet engine

    NASA Technical Reports Server (NTRS)

    Fleming, William A; Wallner, Lewis E

    1948-01-01

    Thrust augmentation of an axial-flow type turbojet engine by burning fuel in the tail pipe has been investigated in the NACA Cleveland altitude wind tunnel. The performance was determined over a range of simulated flight conditions and tail-pipe fuel flows. The engine tail pipe was modified for the investigation to reduce the gas velocity at the inlet of the tail-pipe combustion chamber and to provide an adequate seat for the flame; four such modifications were investigated. The highest net-thrust increase obtained in the investigation was 86 percent with a net thrust specific fuel consumption of 2.91 and a total fuel-air ratio of 0.0523. The highest combustion efficiencies obtained with the four configurations ranged from 0.71 to 0.96. With three of the tail-pipe burners, for which no external cooling was provided, the exhaust nozzle and the rear part of the burner section were bright red during operation at high tail-pipe fuel-air ratios. With the tail-pipe burner for which fuel and water cooling were provided, the outer shell of the tail-pipe burner showed no evidence of elevated temperatures at any operating condition.

  2. Attic Inlet Technology Update

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Attic inlets are a popular addition for new construction and energy saving retrofits. Proper management of attic inlets is necessary to get maximum benefits from the system and reduce the likelihood of moisture-related problems in the structure. Solar energy levels were determined for the continen...

  3. Stepped inlet optical panel

    DOEpatents

    Veligdan, James T.

    2001-01-01

    An optical panel includes stacked optical waveguides having stepped inlet facets collectively defining an inlet face for receiving image light, and having beveled outlet faces collectively defining a display screen for displaying the image light channeled through the waveguides by internal reflection.

  4. Supersonic Elliptical Ramp Inlet

    NASA Technical Reports Server (NTRS)

    Adamson, Eric E. (Inventor); Fink, Lawrence E. (Inventor); Fugal, Spencer R. (Inventor)

    2016-01-01

    A supersonic inlet includes a supersonic section including a cowl which is at least partially elliptical, a ramp disposed within the cowl, and a flow inlet disposed between the cowl and the ramp. The ramp may also be at least partially elliptical.

  5. 46 CFR 193.15-15 - Piping.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... fittings shall have a bursting pressure of not less than 6,000 pounds per square inch. (b) All piping, in... by blowing out the piping with air at a pressure of at least 100 pounds per square inch....

  6. 46 CFR 193.15-15 - Piping.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... fittings shall have a bursting pressure of not less than 6,000 pounds per square inch. (b) All piping, in... by blowing out the piping with air at a pressure of at least 100 pounds per square inch....

  7. 46 CFR 193.15-15 - Piping.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... fittings shall have a bursting pressure of not less than 6,000 pounds per square inch. (b) All piping, in... by blowing out the piping with air at a pressure of at least 100 pounds per square inch....

  8. Water flows from slotted pipes

    SciTech Connect

    Olson, D.A.

    1981-04-01

    Results of experiments and analyses that determine jet flow distribution from slotted pipes of dimensions typical for OC-OTEC evaporators or condensers are described. For a pipe with a 6.3-cm inside diameter and 0.64-cm wide slot, the measured and predicted jet flow was low and nearly parallel to the pipe at the entrance, and high and perpendicular to the pipe only near the closed end. Slot lengths ranged from 1.5 m to 4.6 m, and inlet flow rates varied from 6 kg/s to 17 kg/s. Friction reduces the pressure in the entrance and intermediate portions of the pipe, while the rapidly decelerating flow produces high pressure recovery as it approaches the closed end. In the region of high flow next to the closed end, the ratio of slot area (slot length times width) to pipe cross-sectional area is less than two. To use a slotted pipe for generating falling jets in an OC-OTEC plant, the slot length should be 1 m or less (for a pipe with a 6.3-cm inside diameter and a 0.64-cm wide slot).

  9. Air Mobile Utility Distribution Systems.

    DTIC Science & Technology

    WATER PIPES, AIR TRANSPORTABLE EQUIPMENT, POLYVINYL CHLORIDE, GLASS REINFORCED PLASTICS , FUEL HOSES, HOSES....PIPES, *PIPING SYSTEMS, INSULATION, FABRICATION, CORROSION INHIBITION, FEASIBILITY STUDIES, AIR FORCE FACILITIES, POLYURETHANE RESINS, PLASTICS

  10. Heat Pipes

    ERIC Educational Resources Information Center

    Lewis, J.

    1975-01-01

    Describes the construction, function, and applications of heat pipes. Suggests using the heat pipe to teach principles related to heat transfer and gives sources for obtaining instructional kits for this purpose. (GS)

  11. Pipe Dreams.

    ERIC Educational Resources Information Center

    Milshtein, Amy

    2002-01-01

    Discusses the importance of attention to plumbing in college facilities, offering examples from various campuses. Addresses preventive maintenance, technology, and piping materials, including the debate between cast iron and PVC for drain pipes. (EV)

  12. Flight test results of an automatic support system on board a YF-12A airplane. [for jet engine inlet air control

    NASA Technical Reports Server (NTRS)

    Love, J. E.

    1974-01-01

    An automatic support system concept that isolated faults in an existing nonavionics subsystem was flight tested up to a Mach number of 3. The adaptation of the automated support concept to an existing system (the jet engine automatic inlet control system) caused most of the problems one would expect to encounter in other applications. These problems and their solutions are discussed. Criteria for integrating automatic support into the initial design of new subsystems are included in the paper. Cost effectiveness resulted from both the low maintenance of the automated system and the man-hour saving resulting from the real time diagnosis of the monitored subsystem.

  13. Heat pipe cooling for scramjet engines. Final report

    SciTech Connect

    Silverstein, C.C.

    1986-12-01

    Liquid metal heat pipe cooling systems have been investigated for the combustor liner and engine inlet leading edges of scramjet engines for a missile application. The combustor liner is cooled by a lithium-TZM molybdenum annular heat pipe, which incorporates a separate lithium reservoir. Heat is initially absorbed by the sensible thermal capacity of the heat pipe and liner, and subsequently by the vaporization and discharge of lithium to the atmosphere. The combustor liner temperature is maintained at 3400 F or less during steady-state cruise. The engine inlet leading edge is fabricated as a sodium-superalloy heat pipe. Cooling is accomplished by radiation of heat from the aft surface of the leading edge to the atmosphere. The leading edge temperature is limited to 1700 F or less. It is concluded that heat pipe cooling is a viable method for limiting scramjet combustor liner and engine inlet temperatures to levels at which structural integrity is greatly enhanced.

  14. Improving commercial broiler attic inlet ventilation thorugh CFD analysis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The use of solar heated attic air is an area of increasing interest in commercial poultry production. Attic inlets satisfy the demand for alternative heating while being simple to implement in an existing poultry house. A number of demonstration projects have suggested that attic inlets may decrease...

  15. Inlet Geomorphology Evolution Work Unit

    DTIC Science & Technology

    2015-10-30

    Coastal Inlets Research Program Inlet Geomorphology Evolution Work Unit The Inlet Geomorphology Evolution work unit of the CIRP develops methods...morphologic response. Presently, the primary tool of the Inlet Geomorphology Evolution work unit is the Sediment Mobility Tool (SMT), which allows the user

  16. System for Testing Thermal Insulation of Pipes

    NASA Technical Reports Server (NTRS)

    Fesmire, James E.; Augustynowicz, Stanislaw D.; Nagy, Zoltan F.

    2003-01-01

    An apparatus and method have been developed for measuring the rates of leakage of heat into pipes carrying liquids, the purpose of the measurements being to quantify the thermal performance of the insulation system. The apparatus is designed primarily for testing pipes used to carry cryogenic liquids, but can also be used for measuring the thermal performance of other insulated pipes or piping systems. The basic measurement principle is straightforward: The outer surface of the pipe insulation is maintained at a fixed warmer temperature. The interior of the pipe is maintained in a narrow fixed lower-temperature range by means of a regular liquid (e.g., water) that is pumped through the pipe at a known flow rate or a cryogenic liquid (e.g., nitrogen) that is saturated at atmospheric pressure and replenished until steady-state conditions are achieved. In the case of water or another liquid pumped through, the inlet and outlet temperatures are measured and heat-leak power is calculated as the mass flow rate of the liquid multiplied by the specific heat of the liquid multiplied by the inlet-to-outlet temperature rise of the liquid. In the case of liquid nitrogen or another low-temperature boiling liquid, the heat-leak power is calculated as the rate of boil-off multiplied by the latent heat of vaporization of the liquid. Then the thermal-insulation performance of the pipe system can be calculated as a function of the measured heat-leak power, the inner and outer boundary temperatures, and the dimensions of the pipe. The apparatus can test as many as three pipes simultaneously. The pipes can have inner diameters up to .15 cm and outer diameters up to .20 cm. The lengths of the pipes may vary; typical lengths are of the order of 18 m. Two thermal guard boxes . one for each end of the pipe(s) under test . are used to make the inlet and outlet fluid connections to the pipe(s) (see figure). The connections include bellows that accommodate thermal expansion and contraction

  17. Heat transfer in turbulent decaying swirl flow in a circular pipe

    NASA Astrophysics Data System (ADS)

    Algifri, A. H.; Bhardwaj, R. K.; Rao, Y. V. N.

    1988-08-01

    Heat transfer coefficients for air are measured along a heated pipe for decaying swirl flow, generated by radial blade cascade. The results are compared with an expression proposed for predicting the heat transfer coefficients in swirling flow. The theoretical predictions are in good agreement with the experimental data, with average and maximum deviations of 7 and 11 percent, respectively. The application of the theoretical approach to the experimental results obtained by other investigators for heat transfer in a decaying swirl flow generated by short-twisted tapes and tangential slots at inlet also give rise to encouraging agreement.

  18. Effects on inlet technology on cruise speed selection

    NASA Technical Reports Server (NTRS)

    Bangert, L. H.; Santman, D. M.; Horie, G.; Miller, L. D.

    1980-01-01

    The impact of cruise speed on technology level for certain aircraft components is examined. External-compression inlets were compared with mixed compression, self starting inlets at cruise Mach numbers of 2.0 and 2.3. Inlet engine combinations that provided the greatest aircraft range were identified. Results show that increased transonic to cruise corrected air flow ratio gives decreased range for missions dominated by supersonic cruise. It is also found important that inlets be designed to minimize spillage drag at subsonic cruise, because of the need for efficient performance for overland operations. The external compression inlet emerged as the probable first choice at Mach 2.0, while the self starting inlet was the probable first choice at Mach 2.3. Airframe propulsion system interference effects were significant, and further study is needed to assess the existing design methods and to develop improvements.

  19. CFD numerical simulation of Archimedes spiral inlet hydrocyclone

    NASA Astrophysics Data System (ADS)

    Zhang, L.; Wei, L.; Chang, B. H.; Xing, J. L.; Jia, K.

    2013-12-01

    For traditional linear type inlet, hydrocyclone has an unstable inner field, high turbulence intensity and low separation efficiency, this paper proposes an inlet mode that uses an Archimedes spiral hydrocyclone. A Mixture liquid-solid multiphase flow model combined with the kinetic theory of granular flow was used to simulate the high concentration water-sand-air three-phase flow in a hydrocyclone. We analyzed the pressure field, velocity field and turbulent kinetic energy and compared with traditional linear type inlet hydrocyclone inner field. The results show that Archimedes spiral inlet hydrocyclone's pressure field is evenly distributed. The Archimedes spiral inlet hydrocyclone can guide and accelerate the mixture flow and produce small forced vortex and less short circuit flow. The particles easily go to the outer vortex and are separated. The Archimedes spiral inlet hydrocyclone has effectively improved the stability of inner flow field and separation efficiency.

  20. Phase Distribution Characteristics of Bubbly Flow in Mini Pipes Under Normal and Microgravity Conditions

    NASA Astrophysics Data System (ADS)

    Hazuku, Tatsuya; Takamasa, Tomoji; Hibiki, Takashi

    2015-03-01

    The axial development of the void fraction, interfacial area concentration and Sauter mean bubble diameter profiles of adiabatic air-water bubbly flows in 5.0 and 3.0 mm-diameter pipes were measured using a stereo image processing method under two gravity conditions, vertical upward (normal gravity) and microgravity. The flow measurements were performed at four axial locations. The axial distances from the pipe inlet ( z) normalized by the pipe diameter ( D) were z/ D = 5.5, 34, 72 and 110 for 5.0 mm-diameter pipe and z/ D = 15, 62, 120 and 188 for 3.0 mm-diameter pipe. Data were collected for superficial gas and liquid velocities respectively in the ranges of 0.00434-0.0500 m/s and 0.205-0.754 m/s. The effect of gravity on the radial distribution of bubbles and the axial development of two-phase flow parameters is discussed in detail, based on the obtained database. The phase distributions in pipe cross-sections were classified into 3 basic patterns: core peak, intermediate peak and wall peak distributions, based on two normalized parameters: a normalized void peak position and a normalized void peak intensity. Phase distribution pattern maps under normal and microgravity conditions were generated for bubbly flows in 5.0 and 3.0 mm-diameter pipes. The data obtained in the current experiment are expected to contribute to the benchmarking of CFD simulation of void fraction and interfacial area concentration distribution patterns in forced convective pipe flow under microgravity conditions.

  1. Inlet starting predictions for sidewall-compression scramjet inlets

    NASA Technical Reports Server (NTRS)

    Trexler, Carl A.

    1988-01-01

    While inlet capture, total pressure recovery, and compression are important performance parameters in the design of scramjet inlets, the inlet must be capable of starting. An analytical, inviscid method has been developed that provides first order starting information for sidewall-compression scramjet inlets and trends have been established for some of the parameters that affect inlet starting. These parameters include sidewall contraction ratio, cowl position, Mach number, sweep angle, fuel injection struts, and sidewall and strut compression angles. Results from the parametric study are compared with data from both no-strut and two-strut inlet models.

  2. Inlet Performance Characteristics from Wind-Tunnel Tests of a 0.10-Scale Air-Induction System Model of the YF-108A Airplane at Mach Numbers of 2.50, 2.76, and 3.00

    NASA Technical Reports Server (NTRS)

    Blackaby, James R.; Lyman, E. Gene; Altermann, John A., III

    1959-01-01

    Inlet-performance and external-drag-coefficient characteristics are presented without analysis. Effects are shown of variations of fuselage boundary-layer diverter profile, bleed-surface porosity, bleed-exit area, and inlet ramp, and lip angle.

  3. Cavitation performance and flow characteristic in a centrifugal pump with inlet guide vanes

    NASA Astrophysics Data System (ADS)

    Tan, L.; Zha, L.; Cao, S. L.; Wang, Y. C.; Gui, S. B.

    2015-01-01

    The influence of prewhirl regulation by inlet guide vanes (IGVs) on cavitation performance and flow characteristic in a centrifugal pump is investigated. At the impeller inlet, the streamlines are regulated by the IGVs, and the axial velocity distribution is also influenced by the IGVs. Due to the total pressure loss on the IGVs, the cavitation performance of the centrifugal pump degrades. The cavitation area in impeller with IGVs is larger than one without IGVs. The specify values of total pressure loss between the suction pipe inlet and impeller inlet for three cavitation conditions show that the IGVs will generate additional pressure loss, which is related to the IGVs angles and cavitation conditions.

  4. Influence of the penstock design on the operation of the inlet spherical valves

    NASA Astrophysics Data System (ADS)

    Kolesnikov, A.; Nikiforov, A.

    2014-03-01

    Spherical valves are supplied for high-head turbines. The drive of spherical valves designed and manufactured by Power Machines/LMZ provides opening by means of servomotors, and closing under the action of the moment created by counterweights. Selection of parameters for the spherical valve and its design are based on the assumption continuity of the water flow entering the turbine through the penstock. In case, when two or more hydro-units are installed at the HPP, the penstocks usually have pipe bifurcations (Fig.1). The design of the penstock should provide a uniform supply of water to all units without spin, rupture of continuity and pulsation. Given in the paper is an example of the HPP with two (2) hydro-units equipped with inlet spherical valves. In the course of operation valve rotor oscillations with different periods in time (T ≈ 15 sec.) were detected. When analyzing, no faults in the valve design and its mechanism of operation were detected. In the course of the tests, vibration parameters of the spherical valves were determined in the following operating conditions: each of the hydro-units running separately and both of them running simultaneously for different power output values. Based on the test results, operating conditions with maximum vibration of were located. The reasons of surging of perturbing forces acting on the rotor of the spherical valve were detected in the course of analysis of the penstock design. Possibility of accumulation of air at the penstock pipe bifurcations was found. When the air transported by the water achieved its critical value, this air appeared to be the cause of instability in the valve operation. The attention was drawn to necessity of taking into account this circumstance when designing penstock pipe bifurcations.

  5. Coastal Inlets Research Program

    DTIC Science & Technology

    2014-04-01

    Tech Report: Fate of fines through the dredging process Inlet Geomorphology FY14 Plans  CHETN: Nearshore Berm Working Meeting Summary of Future... Geomorphology FY13 Accomplishments Release 3D Sediment Resource Tool Nearshore Berm Publications Ft Myers Nearshore• Integrated to GMS • Designed to provide 3D

  6. Jet Inlet Efficiency

    DTIC Science & Technology

    2013-08-08

    AFRL-RW-EG-TR-2014-044 Jet Inlet Efficiency Nigel Plumb Taylor Sykes -Green Keith Williams John Wohleber Munitions Aerodynamics Sciences...CONTRACT NUMBER N/A 5b. GRANT NUMBER N/A 5c. PROGRAM ELEMENT NUMBER N/A 6. AUTHOR(S) Nigel Plumb Taylor Sykes -Green Keith Williams John

  7. Monitoring pipes for residual alpha contamination

    SciTech Connect

    MacArthur, D.; Rawool-Sullivan, M.; Dockray, T.

    1996-09-01

    The sensitivity and application of traditional alpha monitors is limited by the short range of alpha particles in air and in solid materials. Detecting small amounts of alpha-emitting contamination inside pipes presents particular problems. The alpha particle cannot penetrate the walls of the pipe. Associated gamma-ray detection and active neutron interrogation is often used to detect large amounts of radioactive material in pipes, but these methods are of limited use for detecting small amounts of contamination. Insertion of a traditional alpha probes works well in large diameter straight pipes, but is increasingly difficult as the pipe network becomes smaller in diameter and more complex. Monitors based on long-range alpha detection (LRAD) detect ionization of the ambient air rather than the alpha particles themselves. A small fan draws the ions into an externally mounted ion detector. Thus, the air in the pipe serves as both the detector gas and the mechanism for transporting the alpha-induced ions to a detection grid outside the pipe. All of the ions created by all of the contamination in the pipe can be measured in a single detector. Since ambient air serves as the probe, crushed or twisted sections of pipe can be monitored almost as effectively as straight sections. The pipe monitoring system described in the paper was tested both at LANL and BNFL`s Sellafield reprocessing facility in the UK. In this paper, we report on the first field tests of the pipe monitoring system.

  8. Optimal Number of Thermoelectric Couples in a Heat Pipe Assisted Thermoelectric Generator for Waste Heat Recovery

    NASA Astrophysics Data System (ADS)

    Liu, Tongjun; Wang, Tongcai; Luan, Weiling; Cao, Qimin

    2017-01-01

    Waste heat recovery through thermoelectric generators is a promising way to improve energy conversion efficiency. This paper proposes a type of heat pipe assisted thermoelectric generator (HP-TEG) system. The expandable evaporator and condenser surface of the heat pipe facilitates the intensive assembly of thermoelectric (TE) modules to compose a compact device. Compared with a conventional layer structure thermoelectric generator, this system is feasible for the installment of more TE couples, thus increasing power output. To investigate the performance of the HP-TEG and the optimal number of TE couples, a theoretical model was presented and verified by experiment results. Further theoretical analysis results showed the performance of the HP-TEG could be further improved by optimizing the parameters, including the inlet air temperature, the thermal resistance of the heating section, and thermal resistance of the cooling structure. Moreover, applying a proper number of TE couples is important to acquire the best power output performance.

  9. Observations of Currents in Two Tidally Modulated Inlets

    NASA Astrophysics Data System (ADS)

    Lippmann, T. C.; Irish, J. D.; Hunt, J.

    2012-12-01

    Observations of currents obtained in two tidally modulated inlets are used to examine the spatial evolution of the vertical structure in hourly averaged mean flow and at tidal frequencies. Field experiments of 30 day duration were conducted at Hampton/Seabrook Harbor, NH, in the Fall of 2011 and again at New River Inlet, NC, in the spring of 2012. The temporal variation and vertical structure of the currents were observed with 600 khz and 1200 khz RDI Acoustic Doppler Current Profilers (ADCP) deployed on low-profile bottom tripods just outside and within the inlet mouth, and with a Nortek Aquadopp Profiler mounted on a jetted pipe on the flank of the inlet channel. Across-inlet current profiles were obtained at each site at various tidal stages with a 1200 khz RDI vessel-mounted ADCP onboard the personal watercraft (the Coastal Bathymetry Survey System, or CBASS) that transited the inlet multiple times at various spatial locations. Flows within the inlet were dominated by semi-diurnal tides, ranging from 2.5 to 4 m in elevation at Hampton/Seabrook Harbor with velocities exceeding 3 m/s, and tides ranging from 1 to 1.5 m in elevation at New River Inlet with velocities exceeding 2 m/s. Flows sampled with the CBASS will be used to examine the horizontal and vertical variation in mean currents (averaged over about 20 - 40 min) at various tidal stages. Currents sampled with the fixed instruments will be used to examine the temporal variation in amplitude and direction of mean currents (averaged over 30 - 60 min) as a function of depth, as well as the amplitude, phase, and rotational structure at tidal frequencies. Observations from the two field sites will be compared and discussed in terms of the spatial and temporal evolution from outside the river mouth to the inner inlet channels over the fortnightly sampling period.

  10. Atrazine sorption by biochar, tire chips, and steel slag as media for blind inlets: A kinetic and isotherm sorption approach

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Surface inlets are installed in subsurface drainage systems to reduce ponding duration and surface runoff, but can contribute to water quality concerns by allowing water to directly enter buried drains. Blind inlets, consist of perforated pipes covered with gravel and are separated from an overlying...

  11. Quantitative comparison of a flared and a standard heated metal capillary inlet with a voltage-assisted air amplifier on an electrospray ionization linear ion trap mass spectrometer.

    PubMed

    Dixon, R Brent; Muddiman, David C

    2007-01-01

    The performance characteristics (i.e., ion abundance and electrospray ion current) of a flared and blunt-ended heated metal capillary were evaluated with a voltage-assisted air amplifier on a linear ion trap mass spectrometer (LTQ-MS). The results demonstrated that a standard capillary afforded higher ion abundance than a flared capillary, thus further work is necessary to investigate conditions for which significant benefits with the flared capillary will be observed. The compatibility of a voltage-assisted air amplifier is explored for both types of capillaries and in all cases resulted in improved ion abundance and spray current.

  12. Pipe crawler with stabilizing midsection

    DOEpatents

    Zollinger, W.T.; Treanor, R.C.

    1994-12-27

    A pipe crawler is described having a midsection that provides the stability and flexibility to allow the pipe crawler to negotiate curved and uneven segments of piping while traveling through piping systems. The pipe crawler comprises a front leg assembly, a rear leg assembly, a midsection with a gimbal at each end for connecting the midsection to the front and rear leg assemblies in a flexible manner, and an air cylinder for changing the distance between the front and rear leg assemblies. The pipe crawler moves in ''inch worm'' fashion with the front and rear leg assemblies alternating between an extended and a retracted position as the air cylinder moves the retracted leg assembly forward. The midsection has a plurality of legs extending radially for holding the midsection within a maximum displacement from the piping axis so that the gimbals are not pivoted to extreme angles where they might lock up or seize. When the midsection is displaced sufficiently, its legs with wheels on each end engage the interior surface of the piping and prevent further displacement. Using two gimbals divides the angle between the planes defined by the front and rear leg assemblies which also helps to prevent excessive gimbal pivoting. 5 figures.

  13. Pipe crawler with stabilizing midsection

    DOEpatents

    Zollinger, William T.; Treanor, Richard C.

    1994-01-01

    A pipe crawler having a midsection that provides the stability and flexibty to allow the pipe crawler to negotiate curved and uneven segments of piping while traveling through piping systems. The pipe crawler comprises a front leg assembly, a rear leg assembly, a midsection with a gimbal at each end for connecting the midsection to the front and rear leg assemblies in a flexible manner, and an air cylinder for changing the distance between the front and rear leg assemblies. The pipe crawler moves in "inch worm" fashion with the front and rear leg assemblies alternating between an extended and a retracted position as the air cylinder moves the retracted leg assembly forward. The midsection has a plurality of legs extending radially for holding the midsection within a maximum displacement from the piping axis so that the gimbals are not pivoted to extreme angles where they might lock up or seize. When the midsection is displaced sufficiently, its legs with wheels on each end engage the interior surface of the piping and prevent further displacement. Using two gimbals divides the angle between the planes defined by the front and rear leg assemblies which also helps to prevent excessive gimbal pivoting.

  14. Pipe connector

    DOEpatents

    Sullivan, Thomas E.; Pardini, John A.

    1978-01-01

    A safety test facility for testing sodium-cooled nuclear reactor components includes a reactor vessel and a heat exchanger submerged in sodium in the tank. The reactor vessel and heat exchanger are connected by an expansion/deflection pipe coupling comprising a pair of coaxially and slidably engaged tubular elements having radially enlarged opposed end portions of which at least a part is of spherical contour adapted to engage conical sockets in the ends of pipes leading out of the reactor vessel and in to the heat exchanger. A spring surrounding the pipe coupling urges the end portions apart and into engagement with the spherical sockets. Since the pipe coupling is submerged in liquid a limited amount of leakage of sodium from the pipe can be tolerated.

  15. Inlet nozzle assembly

    DOEpatents

    Christiansen, D.W.; Karnesky, R.A.; Knight, R.C.; Precechtel, D.R.; Smith, B.G.

    1985-09-09

    An inlet nozzle assembly for directing coolant into the duct tube of a fuel assembly attached thereto. The nozzle assembly includes a shell for housing separable components including an orifice plate assembly, a neutron shield block, a neutron shield plug, and a diffuser block. The orifice plate assembly includes a plurality of stacked plates of differently configurated and sized openings for directing coolant therethrough in a predesigned flow pattern.

  16. Laboratory exercises on oscillation modes of pipes

    NASA Astrophysics Data System (ADS)

    Haeberli, Willy

    2009-03-01

    This paper describes an improved lab setup to study the vibrations of air columns in pipes. Features of the setup include transparent pipes which reveal the position of a movable microphone inside the pipe; excitation of pipe modes with a miniature microphone placed to allow access to the microphone stem for open, closed, or conical pipes; and sound insulation to avoid interference between different setups in a student lab. The suggested experiments on the modes of open, closed, and conical pipes, the transient response of a pipe, and the effect of pipe diameter are suitable for introductory physics laboratories, including laboratories for nonscience majors and music students, and for more advanced undergraduate laboratories. For honors students or for advanced laboratory exercises, the quantitative relation between the resonance width and damping time constant is of interest.

  17. Investigation of Counter-Flow in a Heat Pipe-Thermoelectric Generator (HPTEG)

    NASA Astrophysics Data System (ADS)

    Remeli, Muhammad Fairuz; Singh, Baljit; Affandi, Nor Dalila Nor; Ding, Lai Chet; Date, Abhijit; Akbarzadeh, Aliakbar

    2016-12-01

    This study explores a method of generating electricity while recovering waste heat through the integration of heat pipes and thermoelectric generators (i.e. HPTEG system). The simultaneous waste heat recovery and power generation processes are achieved without the use of any moving parts. The HPTEG system consists of bismuth telluride thermoelectric generators (TEG), which are sandwiched between two finned pipes to achieve a temperature gradient across the TEG for electricity generation. A counter-flow heat exchanger was built using two separate air ducts. The air ducts were thermally coupled using the HPTEG modules. The evaporator section of the heat pipe absorbed the waste heat in a hot air duct. The heat was then transferred across the TEG surfaces. The condenser section of the HPTEG collected the excess heat from the TEG cold side before releasing it to the cold air duct. A 2-kW electrical heater was installed in the hot air duct to simulate the exhaust gas. An air blower was installed at the inlet of each duct to direct the flow of air into the ducts. A theoretical model was developed for predicting the performance of the HPTEG system using the effectiveness-number of transfer units method. The developed model was able to predict the thermal and electrical output of the HPTEG, along with the rate of heat transfer. The results showed that by increasing the cold air velocity, the effectiveness of the heat exchanger was able to be increased from approximately 52% to 58%. As a consequence of the improved heat transfer, maximum power output of 4.3 W was obtained.

  18. Piping Flexibility

    NASA Technical Reports Server (NTRS)

    1978-01-01

    A NASA computer program aids Hudson Engineering Corporation, Houston, Texas, in the design and construction of huge petrochemical processing plants like the one shown, which is located at Ju'aymah, Saudi Arabia. The pipes handling the flow of chemicals are subject to a variety of stresses, such as weight and variations in pressure and temperature. Hudson Engineering uses a COSMIC piping flexibility analysis computer program to analyze stresses and unsure the necessary strength and flexibility of the pipes. This program helps the company realize substantial savings in reduced engineering time.

  19. Pipe crawler with extendable legs

    DOEpatents

    Zollinger, W.T.

    1992-06-16

    A pipe crawler for moving through a pipe in inchworm fashion having front and rear leg assemblies separated by air cylinders to increase and decrease the spacing between assemblies. Each leg of the four legs of an assembly is moved between a wall-engaging, extended position and a retracted position by a separate air cylinder. The air cylinders of the leg assemblies are preferably arranged in pairs of oppositely directed cylinders with no pair lying in the same axial plane as another pair. Therefore, the cylinders can be as long as a leg assembly is wide and the crawler can crawl through sections of pipes where the diameter is twice that of other sections. The crawler carries a valving system, a manifold to distribute air supplied by a single umbilical air hose to the various air cylinders in a sequence controlled electrically by a controller. The crawler also utilizes a rolling mechanism, casters in this case, to reduce friction between the crawler and pipe wall thereby further extending the range of the pipe crawler. 8 figs.

  20. Pipe crawler with extendable legs

    DOEpatents

    Zollinger, William T.

    1992-01-01

    A pipe crawler for moving through a pipe in inchworm fashion having front and rear leg assemblies separated by air cylinders to increase and decrease the spacing between assemblies. Each leg of the four legs of an assembly is moved between a wall-engaging, extended position and a retracted position by a separate air cylinder. The air cylinders of the leg assemblies are preferably arranged in pairs of oppositely directed cylinders with no pair lying in the same axial plane as another pair. Therefore, the cylinders can be as long a leg assembly is wide and the crawler can crawl through sections of pipes where the diameter is twice that of other sections. The crawler carries a valving system, a manifold to distribute air supplied by a single umbilical air hose to the various air cylinders in a sequence controlled electrically by a controller. The crawler also utilizes a rolling mechanism, casters in this case, to reduce friction between the crawler and pipe wall thereby further extending the range of the pipe crawler.

  1. Permitting Considerations for Installation of Inlet Air Foggers on Simple Cycle Combustion Turbines at the Duke Power Lincoln Combustion Turbine Facility

    EPA Pesticide Factsheets

    This document may be of assistance in applying the New Source Review (NSR) air permitting regulations including the Prevention of Significant Deterioration (PSD) requirements. This document is part of the NSR Policy and Guidance Database. Some documents in the database are a scanned or retyped version of a paper photocopy of the original. Although we have taken considerable effort to quality assure the documents, some may contain typographical errors. Contact the office that issued the document if you need a copy of the original.

  2. 19. Photocopy of drawing (1961 piping drawing by Kaiser Engineers) ...

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

    19. Photocopy of drawing (1961 piping drawing by Kaiser Engineers) PIPING PLANS AND DETAILS FOR VEHICLE SUPPORT BUILDING, SHEET P-1 - Vandenberg Air Force Base, Space Launch Complex 3, Vehicle Support Building, Napa & Alden Roads, Lompoc, Santa Barbara County, CA

  3. Heat pipe turbine vane cooling

    SciTech Connect

    Langston, L.; Faghri, A.

    1995-10-01

    The applicability of using heat pipe principles to cool gas turbine vanes is addressed in this beginning program. This innovative concept involves fitting out the vane interior as a heat pipe and extending the vane into an adjacent heat sink, thus transferring the vane incident heat transfer through the heat pipe to heat sink. This design provides an extremely high heat transfer rate and an uniform temperature along the vane due to the internal change of phase of the heat pipe working fluid. Furthermore, this technology can also eliminate hot spots at the vane leading and trailing edges and increase the vane life by preventing thermal fatigue cracking. There is also the possibility of requiring no bleed air from the compressor, and therefore eliminating engine performance losses resulting from the diversion of compressor discharge air. Significant improvement in gas turbine performance can be achieved by using heat pipe technology in place of conventional air cooled vanes. A detailed numerical analysis of a heat pipe vane will be made and an experimental model will be designed in the first year of this new program.

  4. Heat pipe turbine vane cooling

    SciTech Connect

    Langston, L.; Faghri, A.

    1995-12-31

    The applicability of using heat pipe principles to cool gas turbine vanes is addressed in this beginning program. This innovative concept involves fitting out the vane interior as a heat pipe and extending the vane into an adjacent heat sink, thus transferring the vane incident heat transfer through the heat pipe to heat sink. This design provides an extremely high heat transfer rate and a uniform temperature along the vane due to the internal change of phase of the heat pipe working fluid. Furthermore, this technology can also eliminate hot spots at the vane leading and trailing edges and increase the vane life by preventing thermal fatigue cracking. There is also the possibility of requiring no bleed air from the compressor, and therefore eliminating engine performance losses resulting from the diversion of compressor discharge air. Significant improvement in gas turbine performance can be achieved by using heat pipe technology in place of conventional air cooled vanes. A detailed numerical analysis of a heat pipe vane will be made and an experimental model will be designed in the first year of this new program.

  5. Experimental Study on the Flow Regimes and Pressure Gradients of Air-Oil-Water Three-Phase Flow in Horizontal Pipes

    PubMed Central

    Al-Hadhrami, Luai M.; Shaahid, S. M.; Tunde, Lukman O.; Al-Sarkhi, A.

    2014-01-01

    An experimental investigation has been carried out to study the flow regimes and pressure gradients of air-oil-water three-phase flows in 2.25 ID horizontal pipe at different flow conditions. The effects of water cuts, liquid and gas velocities on flow patterns and pressure gradients have been studied. The experiments have been conducted at 20°C using low viscosity Safrasol D80 oil, tap water and air. Superficial water and oil velocities were varied from 0.3 m/s to 3 m/s and air velocity varied from 0.29 m/s to 52.5 m/s to cover wide range of flow patterns. The experiments were performed for 10% to 90% water cuts. The flow patterns were observed and recorded using high speed video camera while the pressure drops were measured using pressure transducers and U-tube manometers. The flow patterns show strong dependence on water fraction, gas velocities, and liquid velocities. The observed flow patterns are stratified (smooth and wavy), elongated bubble, slug, dispersed bubble, and annular flow patterns. The pressure gradients have been found to increase with the increase in gas flow rates. Also, for a given superficial gas velocity, the pressure gradients increased with the increase in the superficial liquid velocity. The pressure gradient first increases and then decreases with increasing water cut. In general, phase inversion was observed with increase in the water cut. The experimental results have been compared with the existing unified Model and a good agreement has been noticed. PMID:24523645

  6. Ice Protection of Turbojet Engines by Inertia Separation of Water III : Annular Submerged Inlets

    NASA Technical Reports Server (NTRS)

    Von Glahn, Uwe

    1948-01-01

    Aerodynamic and icing studies were conducted on a one-half-scale model of an annular submerged inlet for use with axial-flow turbojet engines. Pressure recoveries, screen radial-velocity profiles, circumferential mass-flow variations, and icing characteristics were determined at the compressor inlet. In order to be effective in maintaining water-free induction air, the inlet gap must be extremely small and ram-pressure recoveries consequently are low, the highest achieved being 65 percent at inlet-velocity ratio of 0.86. All inlets exhibited considerable screen icing. Severe mass-flow shifts occurred at angles of attack.

  7. Apparatus and method for detecting leaks in piping

    DOEpatents

    Trapp, D.J.

    1994-12-27

    A method and device are disclosed for detecting the location of leaks along a wall or piping system, preferably in double-walled piping. The apparatus comprises a sniffer probe, a rigid cord such as a length of tube attached to the probe on one end and extending out of the piping with the other end, a source of pressurized air and a source of helium. The method comprises guiding the sniffer probe into the inner pipe to its distal end, purging the inner pipe with pressurized air, filling the annulus defined between the inner and outer pipe with helium, and then detecting the presence of helium within the inner pipe with the probe as is pulled back through the inner pipe. The length of the tube at the point where a leak is detected determines the location of the leak in the pipe. 2 figures.

  8. Apparatus and method for detecting leaks in piping

    DOEpatents

    Trapp, Donald J.

    1994-01-01

    A method and device for detecting the location of leaks along a wall or piping system, preferably in double-walled piping. The apparatus comprises a sniffer probe, a rigid cord such as a length of tube attached to the probe on one end and extending out of the piping with the other end, a source of pressurized air and a source of helium. The method comprises guiding the sniffer probe into the inner pipe to its distal end, purging the inner pipe with pressurized air, filling the annulus defined between the inner and outer pipe with helium, and then detecting the presence of helium within the inner pipe with the probe as is pulled back through the inner pipe. The length of the tube at the point where a leak is detected determines the location of the leak in the pipe.

  9. Alpha detection in pipes using an inverting membrane scintillator

    SciTech Connect

    Kendrick, D.T.; Cremer, C.D.; Lowry, W.

    1995-10-01

    Characterization of surface alpha emitting contamination inside enclosed spaces such as piping systems presents an interesting radiological measurement challenge. Detection of these alpha particles from the exterior of the pipe is impossible since the alpha particles are completely absorbed by the pipe wall. Traditional survey techniques, using hand-held instruments, simply can not be used effectively inside pipes. Science and Engineering Associates, Inc. is currently developing an enhancement to its Pipe Explorer{trademark} system that will address this challenge. The Pipe Explorer{trademark} uses a unique sensor deployment method where an inverted tubular membrane is propagated through complex pipe runs via air pressure. The inversion process causes the membrane to fold out against the pipe wall, such that no part of the membrane drags along the pipe wall. This deployment methodology has been successfully demonstrated at several DOE sites to transport specially designed beta and gamma, scintillation detectors into pipes ranging in length up to 250 ft.

  10. Heat Pipes

    NASA Technical Reports Server (NTRS)

    1996-01-01

    Heat Pipes were originally developed by NASA and the Los Alamos Scientific Laboratory during the 1960s to dissipate excessive heat build- up in critical areas of spacecraft and maintain even temperatures of satellites. Heat pipes are tubular devices where a working fluid alternately evaporates and condenses, transferring heat from one region of the tube to another. KONA Corporation refined and applied the same technology to solve complex heating requirements of hot runner systems in injection molds. KONA Hot Runner Systems are used throughout the plastics industry for products ranging in size from tiny medical devices to large single cavity automobile bumpers and instrument panels.

  11. Piping Connector

    NASA Technical Reports Server (NTRS)

    1993-01-01

    A complex of high pressure piping at Stennis Space Center carries rocket propellants and other fluids/gases through the Center's Component Test Facility. Conventional clamped connectors tend to leak when propellant lines are chilled to extremely low temperatures. Reflange, Inc. customized an existing piping connector to include a secondary seal more tolerant of severe thermal gradients for Stennis. The T-Con connector solved the problem, and the company is now marketing a commercial version that permits testing, monitoring or collecting any emissions that may escape the primary seal during severe thermal transition.

  12. Pipe gripper

    DOEpatents

    Moyers, S.M.

    1975-12-16

    A device for gripping the exterior surface of a pipe or rod is described which has a plurality of wedges, each having a concave face which engages the outer surface of the pipe and each having a smooth face opposing the concave face. The wedges are seated on and their grooved concave faces are maintained in circular alignment by tapered axial segments of an opening extending through a wedge-seating member. The wedges are allowed to slide across the tapered axial segments so that such a sliding movement acts to vary the diameter of the circular alignment.

  13. Heat-Pipe Array for Large-Area Cooling

    NASA Technical Reports Server (NTRS)

    Edelstein, F.; Brown, R. F.

    1986-01-01

    High rates of heat transfer anticipated. Prototype evaporative cold plate gathers waste heat from equipment mounted on it. Plate made by welding together flanges of several sections of heat pipe. Since plate separates liquid and vapor phases at inlet and outlet ports, eliminates complexities and uncertainties of two-phase flow in zero gravity. On earth, inlet valve enables plate to operate at relatively-large height differences with other plates in same system.

  14. Effect of end-wall boundary layer and inlet turbulence on the flow field structures in the turbine stage

    NASA Astrophysics Data System (ADS)

    Jelinek, Tomas; Straka, Petr; Uruba, Vaclav

    2016-06-01

    The article deals with the effects of the inlet flow parameters on the flow field structures in axial turbine stage. The experiment was performed on the axial turbine stage rig with an air as a working medium. The variable inlet channel produced the different inlet turbulence intensity and different inlet end-wall boundary layer thickness, resp. different inlet velocity distribution was applied. The turbulence was measured by CTA probes. The measured parameters of the inlet velocity distribution and turbulence intensity across the inlet channel height are presented. Based on the experimental inlet parameters the CFD fully turbulent calculation of the flow field was made. The differences in outlet kinetic energy loss, outlet vane angle and the turbulence distribution in the vane mid-span section are depicted. Changes of secondary flow structures with the different inlet end-wall boundary layer thickness were observed on the vane outlet parameters.

  15. 14 CFR 25.1091 - Air induction.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... operating surfaces from being directed into the engine or auxiliary power unit air inlet ducts in hazardous quantities, and the air inlet ducts must be located or protected so as to minimize the ingestion of...

  16. An Experimental Investigation of NACA Submerged Inlets at High Subsonic Speeds I: Inlets Forward of the Wing Leading Edge

    NASA Technical Reports Server (NTRS)

    Hall, Charles F; Barclay, F Dorn

    1948-01-01

    This report covers the first part of an experimental investigation of NACA submerged inlets at four locations on the fuselage of a fighter airplane model for Mach numbers from 0.30 to 0.875. Data are presented showing the characteristics of the model without inlets and with inlets 16.7 percent of the root chord forward of the wing-root leading edge and equipped with small boundary-layer deflectors. The data show that variations in the mass of air entering the inlet had a large effect on the ram-recovery ratio. Representative values of ram-recovery ratio were 0.50 with zero flow, 0.90 with 0.6 mass-flow coefficient, and 0.95 with 1.00 mass-flow coefficient. Variations in Mach number and angle of attack, in general, caused less than a 0.03 variation in the ram-recovery ratio.

  17. The influence of inlet flow condition on the frequency of self-excited jet precession

    NASA Astrophysics Data System (ADS)

    Mi, J.; Nathan, G. J.; Wong, C. Y.

    2006-01-01

    A precessing jet flow can be generated naturally by a fluidic nozzle comprising a cylindrical nozzle-chamber with a large sudden expansion at its inlet and a small lip at its outlet. Such a precessing jet flow is offset with respect to the chamber axis, about which it rotates. The aim of the present study is to investigate the influence of the chamber-inlet configuration on the frequency of such precession. Three different inlet configurations, classified as long pipe, smooth contraction, and sharp-edged orifice plate, are tested. It is found that the frequency of precession from the orifice is highest, whereas that of the pipe jet is lowest. These differences appear to result partly from the distinct differences in their respective initial boundary layers.

  18. A new modeling approach of pressure waves at the inlet of internal combustion engines

    NASA Astrophysics Data System (ADS)

    Chalet, David; Mahé, Alexandre; Hétet, Jean-François; Migaud, Jérôme

    2011-06-01

    This paper presents a new model used to describe the propagation of pressure waves at the inlet systems of internal combustion engine. In the first part, an analogy is made between the compressible air in a pipe and a mechanical ideal mass damper spring system. A new model is then presented and the parameters of this model are determined by the use of an experimental setup (shock tube test bench). With this model, a transfer function is defined in order to link directly the pressure and the air mass flow rate. In the second part, the model is included into an internal combustion engine simulation code. The results obtained with this code are compared to experimental ones which are measured on a one-cylinder engine test bench. This last one is driven by an electric motor in order to study only the effect of the pressure waves on the engine behavior. A good agreement is obtained between the experimental results and the numerical ones and the new approach is an alternative method for modeling the pressure wave phenomena in an internal combustion engine manifold.

  19. Axisymmetric Calculations of a Low-Boom Inlet in a Supersonic Wind Tunnel

    NASA Technical Reports Server (NTRS)

    Chima, Rodrick V.; Hirt, Stefanie M.; Reger, Robert

    2011-01-01

    This paper describes axisymmetric CFD predictions made of a supersonic low-boom inlet with a facility diffuser, cold pipe, and mass flow plug within wind tunnel walls, and compares the CFD calculations with the experimental data. The inlet was designed for use on a small supersonic aircraft that would cruise at Mach 1.6, with a Mach number over the wing of 1.7. The inlet was tested in the 8-ft by 6-ft Supersonic Wind Tunnel at NASA Glenn Research Center in the fall of 2010 to demonstrate the performance and stability of a practical flight design that included a novel bypass duct. The inlet design is discussed here briefly. Prior to the test, CFD calculations were made to predict the performance of the inlet and its associated wind tunnel hardware, and to estimate flow areas needed to throttle the inlet. The calculations were done with the Wind-US CFD code and are described in detail. After the test, comparisons were made between computed and measured shock patterns, total pressure recoveries, and centerline pressures. The results showed that the dual-stream inlet had excellent performance, with capture ratios near one, a peak core total pressure recovery of 96 percent, and a large stable operating range. Predicted core recovery agreed well with the experiment but predicted bypass recovery and maximum capture ratio were high. Calculations of offdesign performance of the inlet along a flight profile agreed well with measurements and previous calculations.

  20. TBCC Inlet Experiments and Analysis

    NASA Technical Reports Server (NTRS)

    Saunders, Dave; Slater, John; Dippold, Vance; Lee, Jinho; Sanders, Bobby; Weir, Lois

    2007-01-01

    A research plan is being implemented at NASA to investigate inlet mode transition for turbine-based combined-cycle (TBCC) propulsion for the hypersonic community. Unresolved issues have remained on how to design an inlet system to supply both a turbine engine and a ram/scramjet flowpath that operate with both high performance and stability. The current plan is aimed at characterizing the design, performance and operability of TBCC inlets through a series of experiments and analyses. A TBCC inlet has been designed that is capable of high performance (near MIL-E-5008B recovery) with smooth transitioning characteristics. Traditional design techniques were used in an innovative approach to balance the aerodynamic and mechanical constraints to create a new TBCC inlet concept. The inlet was designed for top-end Mach 7 scramjet speeds with an over/under turbine that becomes cocooned beyond its Mach 4 peak design point. Conceptually, this propulsion system was picked to meet the needs of the first stage of a two-stage to orbit vehicle. A series of increasing fidelity CFD-based tools are being used throughout this effort. A small-scale inlet experiment is on-going in the GRC 1'x1' Supersonic Wind Tunnel (SWT). Initial results from both the CFD analyses and test are discussed showing that high performance and smooth mode transitions are possible. The effort validates the design and is contributing to a large-scale inlet/propulsion test being planned for the GRC 10' x10' SWT. This large-scale effort provide the basis for a Combined Cycle Engine Testbed, (CCET), that will be able to address integrated propulsion system and controls objectives.

  1. Heat pipe technology

    NASA Technical Reports Server (NTRS)

    1972-01-01

    A bibliography of heat pipe technology to provide a summary of research projects conducted on heat pipes is presented. The subjects duscussed are: (1) heat pipe applications, (2) heat pipe theory, (3) design and fabrication, (4) testing and operation, (5) subject and author index, and (6) heat pipe related patents.

  2. Preliminary Investigation of a Conical Spike Inlet in Combination with a Vertical-wedge Auxiliary Inlet at Mach Number 1.9

    NASA Technical Reports Server (NTRS)

    Beke, Andrew; Allen, John L; Williams, Thomas

    1955-01-01

    Pressure-recovery characteristics of a nacelle-type-spike inlet in combination with a vertical-wedge auxiliary scoop are presented for a free-stream Mach number of 1.9 at zero angle of attack. The auxiliary scoop provided 17 percent additional air flow with a drop in critical pressure recovery from 0.86 to 0.81. However, in terms of inlet-engine matching, the pressure recovery of the undersized spike inlet operating at a specified corrected air flow increased with the scoop open, for example, from 0.69 to 0.81.

  3. Investigation of Aerodynamic and Icing Characteristics of Water-Inertia-Separation Inlets for Turbojet Engines

    NASA Technical Reports Server (NTRS)

    VonGlahn, Uwe; Blatz, R. E.

    1950-01-01

    The results of an investigation of several internal water-inertia-separation inlets consisting of a main duct and an alternate duct designed to prevent automatically the entrance of large quantities of water into a turbojet engine in icing conditions are presented. Total-pressure losses and icing characteristics for a direct-ram inlet and the inertia-separation inlets are compared at similar aerodynamic and simulated icing conditions. Complete ice protection for inlet guide vanes could not be achieved with the inertia-separation inlets investigated. Approximately 8 percent of the volume of water entering the nacelles remained. In the air passing into the compressor inlet. Heavy alternate-duct-elbow ice formations caused by secondary inertia separation resulted in rapid total-pressure losses and decreases in mass flow. The duration in an icing condition for an inertia-separation- inlet, without local surface heating, was increased approximately four times above that for a direct-ram inlet with a compressor-inlet screen. For normal nonicing operation, the inertia-separation- inlet total-pressure losses were comparable to a direct-ram installation. The pressure losses and the circumferential uniformity of the mass flow in all the inlets were relatively independent of angle of attack. Use of an inertia-separation inlet would in most cases require a larger diameter nacelle than a direct-ram inlet in order to obtain an alternate duct sufficiently large to pass the required engine air flow at duct Mach numbers below 1.0 at the minimum area.

  4. Heat pipe radiation cooling (HPRC) for high-speed aircraft propulsion. Phase 2 (feasibility) final report

    SciTech Connect

    Martin, R.A.; Merrigan, M.A.; Elder, M.G.; Sena, J.T.; Keddy, E.S.; Silverstein, C.C.

    1994-03-25

    The National Aeronautics and Space Administration (NASA), Los Alamos National Laboratory (Los Alamos), and CCS Associates are conducting the Heat Pipe Radiation Cooling (HPRC) for High-Speed Aircraft Propulsion program to determine the advantages and demonstrate the feasibility of using high-temperature heat pipes to cool hypersonic engine components. This innovative approach involves using heat pipes to transport heat away from the combustor, nozzle, or inlet regions, and to reject it to the environment by thermal radiation from adjacent external surfaces. HPRC is viewed as an alternative (or complementary) cooling technique to the use of pumped cryogenic or endothermic fuels to provide regenerative fuel or air cooling of the hot surfaces. The HPRC program has been conducted through two phases, an applications phase and a feasibility phase. The applications program (Phase 1) included concept and assessment analyses using hypersonic engine data obtained from US engine company contacts. The applications phase culminated with planning for experimental verification of the HPRC concept to be pursued in a feasibility program. The feasibility program (Phase 2), recently completed and summarized in this report, involved both analytical and experimental studies.

  5. DESIGN AND PERFORMANCE OF A LOW FLOW RATE INLET

    EPA Science Inventory

    Several ambient air samplers that have been designated by the U. S. EPA as Federal Reference Methods (FRMs) for measuring particulate matter nominally less than 10 um (PM10) include the use of a particular inlet design that aspirates particulate matter from the atmosphere at 1...

  6. Shock position sensor for supersonic inlets. [measuring pressure in the throat of a supersonic inlet

    NASA Technical Reports Server (NTRS)

    Dustin, M. O. (Inventor)

    1975-01-01

    Static pressure taps or ports are provided in the throat of a supersonic inlet, and signals indicative of the pressure at each of the ports is fed to respective comparators. Means are also provided for directing a signal indicative of the total throat pressure to the comparators. A periodic signal is superimposed on the total throat pressure so that the signal from the static pressure tabs is compared to a varying scan signal rather than to total throat pressure only. This type of comparison causes each comparator to provide a pulse width modulated output which may vary from 0% 'time on' to 100% 'time on'. The pulse width modulated outputs of the comparators are summed, filtered, and directed to a controller which operates a bypass valve such as a door whereby air is dumped from the inlet to prevent the shock wave from being expelled out the front.

  7. Air

    MedlinePlus

    ... do to protect yourself from dirty air . Indoor air pollution and outdoor air pollution Air can be polluted indoors and it can ... this chart to see what things cause indoor air pollution and what things cause outdoor air pollution! Indoor ...

  8. Sink or swim pipe

    SciTech Connect

    Dubois, B.C.; Rhines, J.A.

    1985-07-01

    The development of a six-inch ID flexible pipe system for use as a rapidly deployable offshore fuel delivery system is described. Pipe design data, pipe construction, and advantages of the offshore petroleum delivery system are discussed.

  9. Isokinetic air sampler

    DOEpatents

    Sehmel, George A.

    1979-01-01

    An isokinetic air sampler includes a filter, a holder for the filter, an air pump for drawing air through the filter at a fixed, predetermined rate, an inlet assembly for the sampler having an inlet opening therein of a size such that isokinetic air sampling is obtained at a particular wind speed, a closure for the inlet opening and means for simultaneously opening the closure and turning on the air pump when the wind speed is such that isokinetic air sampling is obtained. A system incorporating a plurality of such samplers provided with air pumps set to draw air through the filter at the same fixed, predetermined rate and having different inlet opening sizes for use at different wind speeds is included within the ambit of the present invention as is a method of sampling air to measure airborne concentrations of particulate pollutants as a function of wind speed.

  10. Design and Analysis Tools for Supersonic Inlets

    NASA Technical Reports Server (NTRS)

    Slater, John W.; Folk, Thomas C.

    2009-01-01

    Computational tools are being developed for the design and analysis of supersonic inlets. The objective is to update existing tools and provide design and low-order aerodynamic analysis capability for advanced inlet concepts. The Inlet Tools effort includes aspects of creating an electronic database of inlet design information, a document describing inlet design and analysis methods, a geometry model for describing the shape of inlets, and computer tools that implement the geometry model and methods. The geometry model has a set of basic inlet shapes that include pitot, two-dimensional, axisymmetric, and stream-traced inlet shapes. The inlet model divides the inlet flow field into parts that facilitate the design and analysis methods. The inlet geometry model constructs the inlet surfaces through the generation and transformation of planar entities based on key inlet design factors. Future efforts will focus on developing the inlet geometry model, the inlet design and analysis methods, a Fortran 95 code to implement the model and methods. Other computational platforms, such as Java, will also be explored.

  11. Low speed test of the aft inlet designed for a tandem fan V/STOL nacelle

    NASA Technical Reports Server (NTRS)

    Rhoades, W. W.; Ybarra, A. H.

    1980-01-01

    An approximately .25 scale model of a Tandem Fan nacelle designed for a Type A V/STOL aircraft configuration was tested in a 10-by-10 foot wind tunnel. A 12 inch, tip driven, turbofan simulator was used to provide the suction source for the aft fan inlet. The front fan inlet was faired over for this test entry. Model variables consisted of a long aft inlet cowl, a short aft inlet cowl, a shaft simulator, blow-in door passages and diffuser vortex generators. Inlet pressure recovery, distortion, inlet angle of attack separation limits were evaluated at tunnel velocities from 0 to 240 knots, angles of attack from -10 to 40 degrees and inlet flow rates representative of throat Mach numbers of 0.1 to 0.6. High inlet performance and stable operation was verified at all design forward speed and angle of attack conditions. The short aft inlet configuration provided exceptionally high pressure recovery except at the highest combination of angle of attack and forward speed. The flow quality at the fan face was somewhat degraded by the addition of blow-in door passages to the long aft inlet configuration due to the pressure disturbances generated by the flow entering the diffuser through the auxiliary air passages.

  12. Air ejector augmented compressed air energy storage system

    DOEpatents

    Ahrens, F.W.; Kartsounes, G.T.

    Energy is stored in slack demand periods by charging a plurality of underground reservoirs with air to the same peak storage pressure, during peak demand periods throttling the air from one storage reservoir into a gas turbine system at a constant inlet pressure until the air presure in the reservoir falls to said constant inlet pressure, thereupon permitting air in a second reservoir to flow into said gas turbine system while drawing air from the first reservoir through a variable geometry air ejector and adjusting said variable geometry air ejector, said air flow being essentially at the constant inlet pressure of the gas turbine system.

  13. Air ejector augmented compressed air energy storage system

    DOEpatents

    Ahrens, Frederick W.; Kartsounes, George T.

    1980-01-01

    Energy is stored in slack demand periods by charging a plurality of underground reservoirs with air to the same peak storage pressure, during peak demand periods throttling the air from one storage reservoir into a gas turbine system at a constant inlet pressure until the air pressure in the reservoir falls to said constant inlet pressure, thereupon permitting air in a second reservoir to flow into said gas turbine system while drawing air from the first reservoir through a variable geometry air ejector and adjusting said variable geometry air ejector, said air flow being essentially at the constant inlet pressure of the gas turbine system.

  14. Computational Analysis of the Large Scale Low-Boom Supersonic Inlet

    NASA Technical Reports Server (NTRS)

    Chima, ROdrick V.

    2011-01-01

    This presentation describes two computational fluid dynamic (CFD) analyses done in support of a supersonic inlet test performed at NASA Glenn Research Center in the fall of 2010. The large-scale-low-boom supersonic inlet was designed for a small supersonic aircraft that would cruise at a Mach number of 1.6. It uses an axisymmetric, external compression spike to reduce the Mach number to 0.65 at the fan face. The inlet was tested in the 8x6 supersonic wind tunnel at NASA GRC using conventional pressure probes, pressure sensitive paint, and high-speed schlieren. Two CFD analyses of the inlet were performed before the test, and compared to the experimental data afterwards. Both analyses used the WIND-US code. First, an axisymmetric analysis of the inlet, diffuser, cold pipe, and mass flow plug was performed to predict the performance of the entire system in the wind tunnel. Then a 3-D analysis of the inlet with all its interior struts was performed to predict details of the flow field and effects of angle of attack. Test results showed that the inlet had excellent performance, with a peak total pressure recovery of 96 percent, and a buzz point far outside the engine operating range. The computations agreed very well with the data, with predicted recoveries within 0.3 - 0.5 points of the measurements.

  15. ONE MILLION GALLON WATER TANK, PUMP HEADER PIPE (AT LEFT), ...

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

    ONE MILLION GALLON WATER TANK, PUMP HEADER PIPE (AT LEFT), HEADER BYPASS PIPE (AT RIGHT), AND PUMPHOUSE FOUNDATIONS. Looking northeast - Edwards Air Force Base, Air Force Rocket Propulsion Laboratory, Flame Deflector Water System, Test Area 1-120, north end of Jupiter Boulevard, Boron, Kern County, CA

  16. Analysis of an advanced ducted propeller subsonic inlet

    NASA Technical Reports Server (NTRS)

    Iek, Chanthy; Boldman, Donald R.; Ibrahim, Mounir

    1992-01-01

    A time marching Navier-Stokes code called PARC (PARC2D for 2-D/axisymmetric and PARC3D for 3-D flow simulations) was validated for an advanced ducted propeller (ADP) subsonic inlet. The code validation for an advanced ducted propeller (ADP) subsonic inlet. The code validation was implemented for a non-separated flow condition associated with the inlet operating at angles-of-attack of 0 and 25 degrees. The inlet test data were obtained in the 9 x 15 ft Low Speed Wind Tunnel at NASA Lewis Research Center as part of a cooperative study with Pratt and Whitney. The experimental study focused on the ADP inlet performance for take-off and approach conditions. The inlet was tested at a free stream Mach number of 0.2, at angles-of-attack between O and 35 degrees, and at a maximum propeller speed of 12,000 RPM which induced a corrected air flow rate of about 46 lb/sec based on standard day conditions. The computational grid and flow boundary conditions (BC) were based on the actual inlet geometry and the funnel flow conditions. At the propeller face, two types of BC's were applied: a mass flow BC and a fixed flow properties BC. The fixed flow properties BC was based on a combination of data obtained from the experiment and calculations using a potential flow code. Comparison of the computational results with the test data indicates that the PARC code with the propeller face fixed flow properties BC provided a better prediction of the inlet surface static pressures than the predictions when the mass flow BC was used. For an angle-of-attack of 0 degrees, the PARC2D code with the propeller face mass flow BC provided a good prediction of inlet static pressures except in the region of high pressure gradient. With the propeller face fixed flow properties BC, the PARC2D code provided a good prediction of the inlet static pressures. For an angle-of-attack of 25 degrees with the mass flow BC, the PARC3D code predicted statis pressures which deviated significantly from the test data

  17. Characterization of radioactive contamination inside pipes with the Pipe Explorer{sup trademark} system

    SciTech Connect

    Cremer, C.D.; Lowry, W.; Cramer, E.

    1995-10-01

    The U.S. Department of Energy`s nuclear facility decommissioning program needs to characterize radiological contamination inside piping systems before the pipe can be recycled, remediated, or disposed. Historically, this has been attempted using hand held survey instrumentation, surveying only the accessible exterior portions of pipe systems. Difficulty, or inability of measuring threshold surface contamination values, worker exposure, and physical access constraints have limited the effectiveness of this approach. Science and Engineering associates, Inc. under contract with the DOE Morgantown Energy Technology Center has developed and demonstrated the Pipe Explorer{trademark} system, which uses an inverting membrane to transport various characterization sensors into pipes. The basic process involves inverting (turning inside out) a tubular impermeable membrane under air pressure. A characterization sensor is towed down the interior of the pipe by the membrane.

  18. Experimental Investigation of Performance and Operating Characterisitics of a Tail-Pipe Burner for a Turbojet Engine

    DTIC Science & Technology

    1947-10-30

    NACA RM No. E7G03 - -- .1 0 - Burner- inlet gas temperature, TB (°F) o 1100 x , ~looo 950 ~ ’750 550 n x A...with inlet -velocity pressure at several burner- inlet gas temperatures for tail-pipe burner Q. . . gFlmTl_Gy- . . . . . NACA RM NO. E7G03 Flg. 9 . a al...WAStiINGTUN --: October 30, 1947 .: .,1 tlFllFWEHTIAlm . .- . . NACA RM No. E7G03 &==Q! -. . . .. .: .. ,,,---.. r. ..,.,. NATIONKL ADVISORY

  19. 46 CFR 154.901 - Atmospheric control within cargo tanks and cargo piping systems.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... within cargo tanks and cargo piping systems. (a) Each vessel must have a piping system for purging each... remaining after purging. (c) For cargo tanks certificated to carry flammable gases, the piping system must allow purging the tank of flammable vapors before air is introduced and purging the tank of air...

  20. Ultrasonic pipe assessment

    DOEpatents

    Thomas, Graham H.; Morrow, Valerie L.; Levie, Harold; Kane, Ronald J.; Brown, Albert E.

    2003-12-23

    An ultrasonic pipe or other structure assessment system includes an ultrasonic transducer positioned proximate the pipe or other structure. A fluid connection between the ultrasonic transducer and the pipe or other structure is produced. The ultrasonic transducer is moved relative to the pipe or other structure.

  1. IPAC-Inlet Performance Analysis Code

    NASA Technical Reports Server (NTRS)

    Barnhart, Paul J.

    1997-01-01

    A series of analyses have been developed which permit the calculation of the performance of common inlet designs. The methods presented are useful for determining the inlet weight flows, total pressure recovery, and aerodynamic drag coefficients for given inlet geometric designs. Limited geometric input data is required to use this inlet performance prediction methodology. The analyses presented here may also be used to perform inlet preliminary design studies. The calculated inlet performance parameters may be used in subsequent engine cycle analyses or installed engine performance calculations for existing uninstalled engine data.

  2. Centrifugal pump inlet pressure site affects measurement.

    PubMed

    Augustin, Simon; Horton, Alison; Butt, Warwick; Bennett, Martin; Horton, Stephen

    2010-09-01

    During extracorporeal life support (ECLS), blood is exposed to a myriad of unphysiological factors that can affect outcome. One aspect of this is the sub-atmospheric pressure generated by the ECLS pump and imparted to blood elements along the pump inlet line. This pressure can be measured on the inlet line close to the pump head by adding a connector, or at the venous cannula connection site. We compared the two measurement sites located at both points; between the venous cannula-inlet tubing and inlet tubing-pump, with a range of cannulae and flows. We also investigated the effects on inlet pressure from pump afterload and increasing inlet tubing length.

  3. Method for Determining Optimum Injector Inlet Geometry

    NASA Technical Reports Server (NTRS)

    Trinh, Huu P. (Inventor); Myers, W. Neill (Inventor)

    2015-01-01

    A method for determining the optimum inlet geometry of a liquid rocket engine swirl injector includes obtaining a throttleable level phase value, volume flow rate, chamber pressure, liquid propellant density, inlet injector pressure, desired target spray angle and desired target optimum delta pressure value between an inlet and a chamber for a plurality of engine stages. The method calculates the tangential inlet area for each throttleable stage. The method also uses correlation between the tangential inlet areas and delta pressure values to calculate the spring displacement and variable inlet geometry of a liquid rocket engine swirl injector.

  4. Chemical laser exhaust pipe design research

    NASA Astrophysics Data System (ADS)

    Sun, Yunqiang; Huang, Zhilong; Chen, Zhiqiang; Ren, Zebin; Guo, Longde

    2016-10-01

    In order to weaken the chemical laser exhaust gas influence of the optical transmission, a vent pipe is advised to emissions gas to the outside of the optical transmission area. Based on a variety of exhaust pipe design, a flow field characteristic of the pipe is carried out by numerical simulation and analysis in detail. The research results show that for uniform deflating exhaust pipe, although the pipeline structure is cyclical and convenient for engineering implementation, but there is a phenomenon of air reflows at the pipeline entrance slit which can be deduced from the numerical simulation results. So, this type of pipeline structure does not guarantee seal. For the design scheme of putting the pipeline contract part at the end of the exhaust pipe, or using the method of local area or tail contraction, numerical simulation results show that backflow phenomenon still exists at the pipeline entrance slit. Preliminary analysis indicates that the contraction of pipe would result in higher static pressure near the wall for the low speed flow field, so as to produce counter pressure gradient at the entrance slit. In order to eliminate backflow phenomenon at the pipe entrance slit, concerned with the pipeline type of radial size increase gradually along the flow, flow field property in the pipe is analyzed in detail by numerical simulation methods. Numerical simulation results indicate that there is not reflow phenomenon at entrance slit of the dilated duct. However the cold air inhaled in the slit which makes the temperature of the channel wall is lower than the center temperature. Therefore, this kind of pipeline structure can not only prevent the leak of the gas, but also reduce the wall temperature. In addition, compared with the straight pipe connection way, dilated pipe structure also has periodic structure, which can facilitate system integration installation.

  5. Comprehensive numerical simulation analysis of flow and mass transfer by tuning inlet conditions in solution circulating technique focused to grow quality KDP crystal

    NASA Astrophysics Data System (ADS)

    Zhang, Xiaoli; Cheng, Min; Yang, Sen; Huang, Yi

    2017-04-01

    The inclusions are easily to be generated because of the nonuniform distribution of supersaturation of crystal surface in KDP crystal growth process, and the inclusions can reduce the growth quality of crystal. So in order to increase the growth rate of crystal and improve the uniformity of surface supersaturation, the numerical simulation of hydrodynamics and mass transfer in the growth of KDP crystal by using solution circulating method have been performed in this paper. The KDP crystal is in eccentric motion in the calculation model, and the effects of inlet velocities, positions of inlet pipe, and incident angles on the crystal growth are discussed. The surface supersaturation and standard deviation of supersaturation are obtained as functions of different inlet velocities, positions of inlet pipe, and incident angles. The value of surface supersaturation is higher and the standard deviation of surface supersaturation is lower when the inlet pipe and crystal are at the same height. Besides, the uniformity of crystal is improved obviously when the axis of inlet pipe is tangent to the rotation track of R-Py tip.

  6. Meeting Review: Airborne Aerosol Inlet Workshop

    NASA Technical Reports Server (NTRS)

    Baumgardner, Darrel; Huebert, Barry; Wilson, Chuck

    1991-01-01

    Proceedings from the Airborne Aerosol Inlet Workshop are presented. The two central topics of discussion were the role of aerosols in atmospheric processes and the difficulties in characterizing aerosols. The following topics were discussed during the working sessions: airborne observations to date; identification of inlet design issues; inlet modeling needs and directions; objectives for aircraft experiments; and future laboratory and wind tunnel studies.

  7. Flexible ocean upwelling pipe

    DOEpatents

    Person, Abraham

    1980-01-01

    In an ocean thermal energy conversion facility, a cold water riser pipe is releasably supported at its upper end by the hull of the floating facility. The pipe is substantially vertical and has its lower end far below the hull above the ocean floor. The pipe is defined essentially entirely of a material which has a modulus of elasticity substantially less than that of steel, e.g., high density polyethylene, so that the pipe is flexible and compliant to rather than resistant to applied bending moments. The position of the lower end of the pipe relative to the hull is stabilized by a weight suspended below the lower end of the pipe on a flexible line. The pipe, apart from the weight, is positively buoyant. If support of the upper end of the pipe is released, the pipe sinks to the ocean floor, but is not damaged as the length of the line between the pipe and the weight is sufficient to allow the buoyant pipe to come to a stop within the line length after the weight contacts the ocean floor, and thereafter to float submerged above the ocean floor while moored to the ocean floor by the weight. The upper end of the pipe, while supported by the hull, communicates to a sump in the hull in which the water level is maintained below the ambient water level. The sump volume is sufficient to keep the pipe full during heaving of the hull, thereby preventing collapse of the pipe.

  8. Swirling flow states in diverging or contracting pipes

    NASA Astrophysics Data System (ADS)

    Rusak, Zvi; Zhang, Yuxin; Li, Harry; Wang, Shixiao

    2015-11-01

    We study the dynamics of inviscid and incompressible swirling flows in diverging or contracting long circular pipes. The inlet flow is described by the circumferential and axial velocity profiles together with a fixed azimuthal vorticity while the outlet flow is characterized by a zero radial velocity state. We first solve the Squire-Long PDE for steady-state flows in a pipe and determine the bifurcation diagram of the various possible flow states as a function of pipe geometry. These include states with a decelerated axial velocity along the pipe center line, an accelerated axial velocity along the pipe center line, vortex breakdown states with a stagnation zone around the pipe center line, and wall-separation states. Then, we establish a correlation between the outlet state of these solutions and solutions of the columnar (x-independent) Squire-Long ODE. Numerical simulations based on the unsteady stream function-circulation equations shed light on the stability of the various steady states and their domain of attraction in terms of initial conditions. The results show that pipe divergence promotes the appearance of vortex breakdown states while pipe contraction induces the formation of wall-separation states.

  9. Optimal control of a supersonic inlet to minimize frequency of inlet unstart

    NASA Technical Reports Server (NTRS)

    Lehtinen, B.; Zeller, J. R.; Geyser, L. C.

    1978-01-01

    A preliminary investigation into the use of modern control theory for the design of controls for a supersonic inlet is described. In particular, the task of controlling a mixed-compression supersonic inlet is formulated as a linear optimal stochastic control and estimation problem. An inlet can exhibit an undesirable instability due to excessive inlet normal shock motion. For the optimal control formulation of the inlet problem, a non quadratic performance index, which is equal to the expected frequency of inlet unstarts, is used. This physically meaningful performance index is minimized for a range of inlet disturbance and measurement noise covariances.

  10. Reusable pipe flange covers

    DOEpatents

    Holden, James Elliott; Perez, Julieta

    2001-01-01

    A molded, flexible pipe flange cover for temporarily covering a pipe flange and a pipe opening includes a substantially round center portion having a peripheral skirt portion depending from the center portion, the center portion adapted to engage a front side of the pipe flange and to seal the pipe opening. The peripheral skirt portion is formed to include a plurality of circumferentially spaced tabs, wherein free ends of the flexible tabs are formed with respective through passages adapted to receive a drawstring for pulling the tabs together on a back side of the pipe flange.

  11. Space shuttle orbiter heat pipe applications. Volume 1: Synopsis

    NASA Technical Reports Server (NTRS)

    Alario, J. P.; Prager, R. C.

    1972-01-01

    An investigation was made to formulate and evaluate heat pipe applications for the space shuttle orbiter. Of the twenty-seven specific applications which were identified, a joint evaluation resulted in the selection of five of the most promising ones for prototype development. The formulation process is described, along with the applications which evolved. The bulk of the discussion deals with the top five applications: (1) heat pipe augmented cold rail; (2) avionics heat pipe circuit; (3) heat pipe/phase change material modular sink; (4) air-to-heat-pipe heat exchanger; and (5) heat pipe radiator for compartment temperature control. The philosophy, physical design details, and performance data are presented for each concept along with a comparison to the baseline design where applicable. A sixth application, heat pipe space radiator for waste heat rejection, was also recommended for prototype development.

  12. Surface Roughness Effects on Light Propagation in Optical Light Pipes

    NASA Astrophysics Data System (ADS)

    Park, Youngjin

    Solid- and hollow-core light pipes are commonly employed to shape the intensity profile of high power lasers for applications in various technology industries such as the automobile, medical, and communications. There are several loss mechanisms present in solid-core glass and polymer light pipes, including absorption, bulk scattering in the material, surface scattering at the material-air interface, and Fresnel Loss at the material-air interface. Fresnel reflection and surface scattering losses typically dominate over other loss mechanisms in solid-core light pipes made of high quality optical materials. In order to analyze the losses in the light pipe, an approximate model is developed and tested using glass and polymer light pipes. The experiements in this thesis focus on analysis of the scattering loss in several optical light pipes configurations. From this analysis, the surface roughness parameters can be determined based on models and comparing with other measurements.

  13. Commercial high efficiency dehumidification systems using heat pipes

    SciTech Connect

    Not Available

    1993-09-01

    An improved heat pipe design using separately connected two-section one-way flow heat pipes with internal microgrooves instead of wicks is described. This design is now commercially available for use to increase the dehumidification capacity of air conditioning systems. The design also includes a method of introducing fresh air into buildings while recovering heat and controlling the humidity of the incoming air. Included are applications and case studies, load calculations and technical data, and installation, operation, and maintenance information.

  14. Heat pipe radiators for space. [vacuum tests

    NASA Technical Reports Server (NTRS)

    Sellers, J. P.

    1977-01-01

    An optimized flight-weight prototype fluid-header panel (heatpipe radiator system) was tested in a vacuum environment over a wide range of coolant inlet temperatures, coolant flow rates, and environmental absorbed heat fluxes. The maximum performance of the system was determined. Results are compared with earlier data obtained on a smaller fluid-header feasibility panel, and computer predictions. Freeze-thaw tests are described and the change in thaw recovery time due to the addition of a low-freezing point feeder heat pipe is evaluated. Experimental panel fin-temperature distributions are compared with calculated results.

  15. ISOTHERMAL AIR INGRESS VALIDATION EXPERIMENTS

    SciTech Connect

    Chang H Oh; Eung S Kim

    2011-09-01

    Idaho National Laboratory carried out air ingress experiments as part of validating computational fluid dynamics (CFD) calculations. An isothermal test loop was designed and set to understand the stratified-flow phenomenon, which is important as the initial air flow into the lower plenum of the very high temperature gas cooled reactor (VHTR) when a large break loss-of-coolant accident occurs. The unique flow characteristics were focused on the VHTR air-ingress accident, in particular, the flow visualization of the stratified flow in the inlet pipe to the vessel lower plenum of the General Atomic’s Gas Turbine-Modular Helium Reactor (GT-MHR). Brine and sucrose were used as heavy fluids, and water was used to represent a light fluid, which mimics a counter current flow due to the density difference between the stimulant fluids. The density ratios were changed between 0.87 and 0.98. This experiment clearly showed that a stratified flow between simulant fluids was established even for very small density differences. The CFD calculations were compared with experimental data. A grid sensitivity study on CFD models was also performed using the Richardson extrapolation and the grid convergence index method for the numerical accuracy of CFD calculations . As a result, the calculated current speed showed very good agreement with the experimental data, indicating that the current CFD methods are suitable for predicting density gradient stratified flow phenomena in the air-ingress accident.

  16. Parametric Inlet Tested in Glenn's 10- by 10-Foot Supersonic Wind Tunnel

    NASA Technical Reports Server (NTRS)

    Slater, John W.; Davis, David O.; Solano, Paul A.

    2005-01-01

    The Parametric Inlet is an innovative concept for the inlet of a gas-turbine propulsion system for supersonic aircraft. The concept approaches the performance of past inlet concepts, but with less mechanical complexity, lower weight, and greater aerodynamic stability and safety. Potential applications include supersonic cruise aircraft and missiles. The Parametric Inlet uses tailored surfaces to turn the incoming supersonic flow inward toward an axis of symmetry. The terminal shock spans the opening of the subsonic diffuser leading to the engine. The external cowl area is smaller, which reduces cowl drag. The use of only external supersonic compression avoids inlet unstart--an unsafe shock instability present in previous inlet designs that use internal supersonic compression. This eliminates the need for complex mechanical systems to control unstart, which reduces weight. The conceptual design was conceived by TechLand Research, Inc. (North Olmsted, OH), which received funding through NASA s Small-Business Innovation Research program. The Boeing Company (Seattle, WA) also participated in the conceptual design. The NASA Glenn Research Center became involved starting with the preliminary design of a model for testing in Glenn s 10- by 10-Foot Supersonic Wind Tunnel (10 10 SWT). The inlet was sized for a speed of Mach 2.35 while matching requirements of an existing cold pipe used in previous inlet tests. The parametric aspects of the model included interchangeable components for different cowl lip, throat slot, and sidewall leading-edge shapes and different vortex generator configurations. Glenn researchers used computational fluid dynamics (CFD) tools for three-dimensional, turbulent flow analysis to further refine the aerodynamic design.

  17. Pipe-to-pipe impact program

    SciTech Connect

    Alzheimer, J.M.; Bampton, M.C.C.; Friley, J.R.; Simonen, F.A.

    1984-06-01

    This report documents the tests and analyses performed as part of the Pipe-to-Pipe Impact (PTPI) Program at the Pacific Northwest Laboratory. This work was performed to assist the NRC in making licensing decisions regarding pipe-to-pipe impact events following postulated breaks in high energy fluid system piping. The report scope encompasses work conducted from the program's start through the completion of the initial hot oil tests. The test equipment, procedures, and results are described, as are analytic studies of failure potential and data correlation. Because the PTPI Program is only partially completed, the total significance of the current test results cannot yet be accurately assessed. Therefore, although trends in the data are discussed, final conclusions and recommendations will be possible only after the completion of the program, which is scheduled to end in FY 1984.

  18. Singing Corrugated Pipes

    ERIC Educational Resources Information Center

    Crawford, Frank S.

    1974-01-01

    Presents theoretical and experimental observations made with a musical toy called Hummer consisting of a corrugated flexible plastic tube about three-feet long and one-inch diam open at both ends. Included are descriptions of three new instruments: the Water Pipe, the Gas-Pipe Corrugahorn Bugle, and the Gas-Pipe Blues Corrugahorn. (CC)

  19. Heat pipes. [technology utilization

    NASA Technical Reports Server (NTRS)

    1975-01-01

    The development and use of heat pipes are described, including space requirements and contributions. Controllable heat pipes, and designs for automatically maintaining a selected constant temperature, are discussed which would add to the versatility and usefulness of heat pipes in industrial processing, manufacture of integrated circuits, and in temperature stabilization of electronics.

  20. Pipe protection bibliography

    SciTech Connect

    Guy, N.G.

    1987-01-01

    Pipes and pipelines are being used for an ever widening range of materials, for increasing flows and in harsher applications. There is also more legal and social pressure to reduce the hazards associated with handling materials in pipes. All of this increases the demand for improved pipe reliability. Two of the major preventable causes of pipe failure are corrosion and wear. These may result from the pipe surroundings, or from the material which is carried and it is often impossible to prevent failure by the choice of pipe materials and design. However, additional pipe protection measures are available and it is these measures which are considered in this bibliography. The most common pipe protection methods are the application of coatings and the use of cathodic protection. Accordingly, much of this bibliography is devoted to these techniques. Articles dealing with other means of protecting pipes have also been included. The bibliography covers the protection of oil pipes, (both offshore and on land); water supply systems; gas distribution systems; sewer pipes; pipes for hydraulic and pneumatic transport of solids; power plant pipework; process plant pipework.

  1. Influence of water flow on pipe inspection

    NASA Astrophysics Data System (ADS)

    Ahmad, Rais; Banerjee, Sourav; Kundu, Tribikram

    2005-05-01

    From various studies by different investigators it has been now well established that a number of cylindrical guided wave modes are sensitive to the pipe wall defects. Several investigations by these authors and other researchers showed that the strengths of the guided waves propagating through a pipe that is placed in air are reduced when the pipe wall defects are encountered. This reduction is expected because the pipe wall defects (gouge, dent, removed metal due to corrosion etc.) alter the pipe geometry, hampering the free propagation of guided wave modes. When water flows through the pipes, the guided wave technique becomes more challenging because the flowing water absorbs part of the propagating acoustic energy. Flowing water may also induce some standing modes. The propagating cylindrical guided wave modes become leaky modes in presence of the flowing water, in other words energy leaks into water. Therefore, the energy detected by a receiver, placed at a large distance from the transmitter, is reduced even for a defect free pipe. Further reduction in the signal strength occurs in presence of defects.

  2. Heat pipe systems using new working fluids

    NASA Technical Reports Server (NTRS)

    Chao, David F. (Inventor); Zhang, Nengli (Inventor)

    2004-01-01

    The performance of a heat pipe system is greatly improved by the use of a dilute aqueous solution of about 0.0005 and about 0.005 moles per liter of a long chain alcohol as the working fluid. The surface tension-temperature gradient of the long-chain alcohol solutions turns positive as the temperature exceeds a certain value, for example about 40.degree. C. for n-heptanol solutions. Consequently, the Marangoni effect does not impede, but rather aids in bubble departure from the heating surface. Thus, the bubble size at departure is substantially reduced at higher frequencies and, therefore, increases the boiling limit of heat pipes. This feature is useful in microgravity conditions. In addition to microgravity applications, the heat pipe system may be used for commercial, residential and vehicular air conditioning systems, micro heat pipes for electronic devices, refrigeration and heat exchangers, and chemistry and cryogenics.

  3. Heat pipe effect in porous medium

    SciTech Connect

    Joseph, M.

    1992-12-01

    In this thesis a parametric study of the thermal and hydrologic characteristics of the fractured porous tuffs at Yucca Mountain, Nevada was conducted. The effects of different fracture and matrix properties including permeability, thermal conductivity, specific heat, porosity, and tortuosity on heat pipe performance in the vicinity of the waste package were observed. Computer simulations were carried out using TOUGH code on a Cray YMP-2 supercomputer. None of the fracture parameters affected the heat pipe performance except the mobility of the liquid in the fracture. Matrix permeability and thermal conductivity were found to have significant effect on the heat pipe performance. The effect of mass injection was studied for liquid water and air injected at the fracture boundary. A high rate of mass injection was required to produce any effect on the heat pipe. The fracture-matrix equilibrium is influenced by the matrix permeability and the matrix thermal conductivity.

  4. Afterburner performance of film-vaporizing V-gutters for inlet temperatures up to 1255 K

    NASA Technical Reports Server (NTRS)

    Branstetter, J. R.; Reck, G. M.

    1973-01-01

    Combustion tests of five variations of an integral, spray-bar - flameholder combination were conducted in a 0.49-m-diameter duct. Emphasis was on low levels of augmentation. Fuel impinged on guide plates, mixed with a controlled amount of inlet air, vaporized, and was guided into the V-gutter wake. Combustor length was 0.92 m. Good performance was demonstrated at fuel-air ratios less than 0.025 for inlet temperatures of 920 to 1255 K. Maximum combustion efficiency occured in the vicinity of fuel-air ratios of 0.02 and was 92 to 100 percent, depending on the inlet temperature. Lean blowout fuel-air ratios were in the vicinity of 0.005. Improvements in rich-limit blowout resulted from enlarging the guide-flow passageway areas. Other means of extending the operating range are suggested. A simplified afterburner concept for application to advanced engines is described.

  5. 14 CFR 252.15 - Cigars and pipes.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 4 2012-01-01 2012-01-01 false Cigars and pipes. 252.15 Section 252.15 Aeronautics and Space OFFICE OF THE SECRETARY, DEPARTMENT OF TRANSPORTATION (AVIATION PROCEEDINGS) ECONOMIC REGULATIONS SMOKING ABOARD AIRCRAFT § 252.15 Cigars and pipes. Air carriers shall prohibit the smoking...

  6. 14 CFR 252.15 - Cigars and pipes.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 4 2014-01-01 2014-01-01 false Cigars and pipes. 252.15 Section 252.15 Aeronautics and Space OFFICE OF THE SECRETARY, DEPARTMENT OF TRANSPORTATION (AVIATION PROCEEDINGS) ECONOMIC REGULATIONS SMOKING ABOARD AIRCRAFT § 252.15 Cigars and pipes. Air carriers shall prohibit the smoking...

  7. 14 CFR 252.15 - Cigars and pipes.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 4 2010-01-01 2010-01-01 false Cigars and pipes. 252.15 Section 252.15 Aeronautics and Space OFFICE OF THE SECRETARY, DEPARTMENT OF TRANSPORTATION (AVIATION PROCEEDINGS) ECONOMIC REGULATIONS SMOKING ABOARD AIRCRAFT § 252.15 Cigars and pipes. Air carriers shall prohibit the smoking...

  8. 14 CFR 252.15 - Cigars and pipes.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 4 2011-01-01 2011-01-01 false Cigars and pipes. 252.15 Section 252.15 Aeronautics and Space OFFICE OF THE SECRETARY, DEPARTMENT OF TRANSPORTATION (AVIATION PROCEEDINGS) ECONOMIC REGULATIONS SMOKING ABOARD AIRCRAFT § 252.15 Cigars and pipes. Air carriers shall prohibit the smoking...

  9. 14 CFR 252.15 - Cigars and pipes.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 4 2013-01-01 2013-01-01 false Cigars and pipes. 252.15 Section 252.15 Aeronautics and Space OFFICE OF THE SECRETARY, DEPARTMENT OF TRANSPORTATION (AVIATION PROCEEDINGS) ECONOMIC REGULATIONS SMOKING ABOARD AIRCRAFT § 252.15 Cigars and pipes. Air carriers shall prohibit the smoking...

  10. 46 CFR 34.15-15 - Piping-T/ALL.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... Systems, Details § 34.15-15 Piping—T/ALL. (a) The piping, valves, and fittings shall have a bursting... be tested by blowing out the piping with the air at a pressure of at least 100 pounds p.s.i....

  11. 46 CFR 34.15-15 - Piping-T/ALL.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... Systems, Details § 34.15-15 Piping—T/ALL. (a) The piping, valves, and fittings shall have a bursting... be tested by blowing out the piping with the air at a pressure of at least 100 pounds p.s.i....

  12. 46 CFR 34.15-15 - Piping-T/ALL.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... Systems, Details § 34.15-15 Piping—T/ALL. (a) The piping, valves, and fittings shall have a bursting... be tested by blowing out the piping with the air at a pressure of at least 100 pounds p.s.i....

  13. 46 CFR 34.15-15 - Piping-T/ALL.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... Systems, Details § 34.15-15 Piping—T/ALL. (a) The piping, valves, and fittings shall have a bursting... be tested by blowing out the piping with the air at a pressure of at least 100 pounds p.s.i....

  14. 257. Photocopy of drawing (1975 piping drawing by the Ralph ...

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

    257. Photocopy of drawing (1975 piping drawing by the Ralph M. Parsons Company) PARTIAL PIPING PLAN OF THE LIQUID OXYGEN STORAGE AREA FOR THE LSB, SHEET P-5 - Vandenberg Air Force Base, Space Launch Complex 3, Launch Pad 3 East, Napa & Alden Roads, Lompoc, Santa Barbara County, CA

  15. Note: A passively cooled heat pipe for spectroscopy.

    PubMed

    Gillot, J; Lemarchand, C; Braud, I; Decamps, B; Gauguet, A; Vigué, J; Büchner, M

    2013-10-01

    We have developed and characterized a heat pipe for lithium spectroscopy, which is cooled only by air-convection, although its operating temperature is 330 °C: its construction is simple, of moderate cost and it is very reliable. A thermal model proves that heat-pipes without water cooling can be used up to considerably higher temperatures.

  16. Pipe Line Control

    NASA Technical Reports Server (NTRS)

    1978-01-01

    The array of tanks, pipes and valves in the photo below is a petroleum tank farm in Georgia, part of a petrochemical pipe line system that moves refined petroleum products from Texas and Louisiana to the mid-Eastern seaboard. The same pipes handle a number of different products, such as gasoline, kerosene, jet fuel or fuel oil. The fluids are temporarily stored in tanks, pumped into the pipes in turn and routed to other way stations along the pipe line. The complex job of controlling, measuring and monitoring fuel flow is accomplished automatically by a computerized control and communications system which incorporates multiple space technologies.

  17. Experimental and numerical investigations on reliability of air barrier on oil containment in flowing water.

    PubMed

    Lu, Jinshu; Xu, Zhenfeng; Xu, Song; Xie, Sensen; Wu, Haoxiao; Yang, Zhenbo; Liu, Xueqiang

    2015-06-15

    Air barriers have been recently developed and employed as a new type of oil containment boom. This paper presents systematic investigations on the reliability of air barriers on oil containments with the involvement of flowing water, which represents the commonly-seen shearing current in reality, by using both laboratory experiments and numerical simulations. Both the numerical and experimental investigations are carried out in a model scale. In the investigations, a submerged pipe with apertures is installed near the bottom of a tank to generate the air bubbles forming the air curtain; and, the shearing water flow is introduced by a narrow inlet near the mean free surface. The effects of the aperture configurations (including the size and the spacing of the aperture) and the location of the pipe on the effectiveness of the air barrier on preventing oil spreading are discussed in details with consideration of different air discharges and velocities of the flowing water. The research outcome provides a foundation for evaluating and/or improve the reliability of a air barrier on preventing spilled oil from further spreading.

  18. Effects of inlet distortion on gas turbine combustion chamber exit temperature profiles

    NASA Astrophysics Data System (ADS)

    Maqsood, Omar Shahzada

    Damage to a nozzle guide vane or blade, caused by non-uniform temperature distributions at the combustion chamber exit, is deleterious to turbine performance and can lead to expensive and time consuming overhaul and repair. A test rig was designed and constructed for the Allison 250-C20B combustion chamber to investigate the effects of inlet air distortion on the combustion chamber's exit temperature fields. The rig made use of the engine's diffuser tubes, combustion case, combustion liner, and first stage nozzle guide vane shield. Rig operating conditions simulated engine cruise conditions, matching the quasi-non-dimensional Mach number, equivalence ratio and Sauter mean diameter. The combustion chamber was tested with an even distribution of inlet air and a 4% difference in airflow at either side. An even distribution of inlet air to the combustion chamber did not create a uniform temperature profile and varying the inlet distribution of air exacerbated the profile's non-uniformity. The design of the combustion liner promoted the formation of an oval-shaped toroidal vortex inside the chamber, creating localized hot and cool sections separated by 90° that appeared in the exhaust. Uneven inlet air distributions skewed the oval vortex, increasing the temperature of the hot section nearest the side with the most mass flow rate and decreasing the temperature of the hot section on the opposite side. Keywords: Allison 250, Combustion, Dual-Entry, Exit Temperature Profile, Gas Turbine, Pattern Factor, Reverse Flow.

  19. Air Conditioner/Dehumidifier

    NASA Technical Reports Server (NTRS)

    1986-01-01

    An ordinary air conditioner in a very humid environment must overcool the room air, then reheat it. Mr. Dinh, a former STAC associate, devised a heat pipe based humidifier under a NASA Contract. The system used heat pipes to precool the air; the air conditioner's cooling coil removes heat and humidity, then the heat pipes restore the overcooled air to a comfortable temperature. The heat pipes use no energy, and typical savings are from 15-20%. The Dinh Company also manufactures a "Z" coil, a retrofit cooling coil which may be installed on an existing heater/air conditioner. It will also provide free hot water. The company has also developed a photovoltaic air conditioner and solar powered water pump.

  20. Aeroacoustic performance of a scoop inlet

    NASA Technical Reports Server (NTRS)

    Abbott, J. M.

    1977-01-01

    A low speed wind tunnel test demonstrated the aerodynamic and acoustic performance of a scoop inlet. Engine noise is directed upward by the extended lower lip of the scoop inlet. In addition, more of the scoop airflow comes in from above the inlet than below, leading to relatively higher surface velocities on the upper lip and lower surface velocities on the lower lip. These lower velocities on the lower lip result in a higher attainable angle of attack before internal flow separation occurs.

  1. Waves, Currents, & Bathymetric Evolution Near Inlets

    DTIC Science & Technology

    2013-09-30

    Jessup , A., R. Holman, C. Chickadel, S. Elgar; G. Farquharson, M . Haller, A. Kurapov, T. Özkan- Haller, B. Raubenheimer, J. Thomson, DARLA: Data...remotely sensed observations ( Jessup et al. 2012). Figure 1. Array of in situ wave and current sensors (white circles) deployed at New River...the inlet channel in depths from 1 to 10 m ]. (ii) Katama Inlet A numerical model for the water levels and flows in a two-inlet system was developed

  2. 49 CFR 178.338-8 - Pressure relief devices, piping, valves, and fittings.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...) Piping, valves, and fittings. (1) The burst pressure of all piping, pipe fittings, hoses and other... pressure of the tank. Additionally, the burst pressure may not be less than 4 times any higher pressure to..., and fittings have been tested after installation with gas or air and proved leak tight at not...

  3. 49 CFR 178.338-8 - Pressure relief devices, piping, valves, and fittings.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...) Piping, valves, and fittings. (1) The burst pressure of all piping, pipe fittings, hoses and other... pressure of the tank. Additionally, the burst pressure may not be less than 4 times any higher pressure to..., and fittings have been tested after installation with gas or air and proved leak tight at not...

  4. 49 CFR 178.338-8 - Pressure relief devices, piping, valves, and fittings.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...) Piping, valves, and fittings. (1) The burst pressure of all piping, pipe fittings, hoses and other... pressure of the tank. Additionally, the burst pressure may not be less than 4 times any higher pressure to..., and fittings have been tested after installation with gas or air and proved leak tight at not...

  5. Axisymmetric inlet minimum weight design method

    NASA Technical Reports Server (NTRS)

    Nadell, Shari-Beth

    1995-01-01

    An analytical method for determining the minimum weight design of an axisymmetric supersonic inlet has been developed. The goal of this method development project was to improve the ability to predict the weight of high-speed inlets in conceptual and preliminary design. The initial model was developed using information that was available from inlet conceptual design tools (e.g., the inlet internal and external geometries and pressure distributions). Stiffened shell construction was assumed. Mass properties were computed by analyzing a parametric cubic curve representation of the inlet geometry. Design loads and stresses were developed at analysis stations along the length of the inlet. The equivalent minimum structural thicknesses for both shell and frame structures required to support the maximum loads produced by various load conditions were then determined. Preliminary results indicated that inlet hammershock pressures produced the critical design load condition for a significant portion of the inlet. By improving the accuracy of inlet weight predictions, the method will improve the fidelity of propulsion and vehicle design studies and increase the accuracy of weight versus cost studies.

  6. Radial inlet guide vanes for a combustor

    DOEpatents

    Zuo, Baifang; Simons, Derrick; York, William; Ziminsky, Willy S

    2013-02-12

    A combustor may include an interior flow path therethrough, a number of fuel nozzles in communication with the interior flow path, and an inlet guide vane system positioned about the interior flow path to create a swirled flow therein. The inlet guide vane system may include a number of windows positioned circumferentially around the fuel nozzles. The inlet guide vane system may also include a number of inlet guide vanes positioned circumferentially around the fuel nozzles and adjacent to the windows to create a swirled flow within the interior flow path.

  7. Planar Inlet Design and Analysis Process (PINDAP)

    NASA Technical Reports Server (NTRS)

    Slater, John W.; Gruber, Christopher R.

    2005-01-01

    The Planar Inlet Design and Analysis Process (PINDAP) is a collection of software tools that allow the efficient aerodynamic design and analysis of planar (two-dimensional and axisymmetric) inlets. The aerodynamic analysis is performed using the Wind-US computational fluid dynamics (CFD) program. A major element in PINDAP is a Fortran 90 code named PINDAP that can establish the parametric design of the inlet and efficiently model the geometry and generate the grid for CFD analysis with design changes to those parameters. The use of PINDAP is demonstrated for subsonic, supersonic, and hypersonic inlets.

  8. Status of the Combined-Cycle Engine Large-Scale Inlet Mode Transition Experiment

    NASA Technical Reports Server (NTRS)

    Slater, John W.; Saunders, J. Dave

    2011-01-01

    The Large-Scale Inlet Mode Transition (LIMX) experiment is currently being conducted in the 10x10 foot supersonic wind tunnel at the NASA Glenn Research Center. The experiment has involved the efforts of a team for over four years to get to the first phase of testing, which is examining the aerodynamic characteristics of the inlet. The LIMX inlet involves dual flowpaths: one to provide flow to a turbine engine and one to provide flow to a dual-mode ramjet/scramjet. A rotating splitter cowl can close off the turbine flowpath, which would occur as the propulsion system transitions from turbine power to ramjet/scramjet power at Mach 4. The first phase of the experiment will simulate the turbine and ramjet/scramjet flows using cold pipes with flow rates controlled by mass-flow plugs. Much of the testing will characterize the performance of the turbine flowpath (total pressure recovery and distortion at the engine face location) as factors such as bleed rates and configuration and vortex generators are varied during the inlet mode transition. The performance of the inlet will also be examined at off-design Mach numbers (2.5-3.0) and at angle-of-attack.

  9. Low flight speed acoustic results for a supersonic inlet with auxiliary inlet doors

    NASA Technical Reports Server (NTRS)

    Woodward, R. P.; Glaser, F. W.; Lucas, J. G.

    1982-01-01

    A model supersonic inlet with auxiliary inlet doors and bounday layer bleeds was acoustically tested in simulated low speed flight up to Mach 0.2 in the NASA Lewis 9x15 Anechoic Wind Tunnel and statically in the NASA Lewis Anechoic Chamber. A JT8D refan model was used as the noise source. Data were also taken for a CTOL inlet and for an annular inlet with simulated centerbody support struts. Inlet operation with open auxiliary doors increased the blade passage tone by about 10 dB relative to the closed door configuration although noise radiation was primarily through the main inlet rather than the doors. Numerous strong spikes in the noise spectra were associated with the bleed system, and were strongly affected by the centerbody location. The supersonic inlet appeared to suppress multiple pure tone (MPT) generation at the fan source. Inlet length and the presence of support struts were shown not to cause this MPT suppression.

  10. 27. GENERAL DETAIL OF PIPING DROPPING FROM ABOVE GRADE INTO ...

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

    27. GENERAL DETAIL OF PIPING DROPPING FROM ABOVE GRADE INTO TRENCH ADJACENT TO PAD AREA; VIEW TO NORTH. - Cape Canaveral Air Station, Launch Complex 17, Facility 28402, East end of Lighthouse Road, Cape Canaveral, Brevard County, FL

  11. 26. DETAIL OF CONCRETE PIPE SUPPORTS LEADING TO NEW LIQUID ...

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

    26. DETAIL OF CONCRETE PIPE SUPPORTS LEADING TO NEW LIQUID HYDROGEN TANK FARM; VIEW TO WEST. - Cape Canaveral Air Station, Launch Complex 17, Facility 28402, East end of Lighthouse Road, Cape Canaveral, Brevard County, FL

  12. 21. Power plant engine fuel oil piping diagrams, sheet 83 ...

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

    21. Power plant engine fuel oil piping diagrams, sheet 83 of 130 - Naval Air Station Fallon, Power Plant, 800 Complex, off Carson Road near intersection of Pasture & Berney Roads, Fallon, Churchill County, NV

  13. DETAIL OF VACUUM PIPE OPENING WITHIN ALTITUDE CHAMBER R, FACING ...

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

    DETAIL OF VACUUM PIPE OPENING WITHIN ALTITUDE CHAMBER R, FACING SOUTHEAST - Cape Canaveral Air Force Station, Launch Complex 39, Altitude Chambers, First Street, between Avenue D and Avenue E, Cape Canaveral, Brevard County, FL

  14. DETAIL OF UTILITY PIPES AND PLATFORM SUPPORT COLUMN, INTERIOR OF ...

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

    DETAIL OF UTILITY PIPES AND PLATFORM SUPPORT COLUMN, INTERIOR OF ALTITUDE CHAMBER L, FACING EAST - Cape Canaveral Air Force Station, Launch Complex 39, Altitude Chambers, First Street, between Avenue D and Avenue E, Cape Canaveral, Brevard County, FL

  15. DETAIL OF UTILITY PIPES AT THE BOTTOM LEVEL OF INTERNAL ...

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

    DETAIL OF UTILITY PIPES AT THE BOTTOM LEVEL OF INTERNAL PLATFORMS, ALTITUDE CHAMBER L, FACING WEST - Cape Canaveral Air Force Station, Launch Complex 39, Altitude Chambers, First Street, between Avenue D and Avenue E, Cape Canaveral, Brevard County, FL

  16. Experimental study on the inlet fogging system using two-fluid nozzles

    NASA Astrophysics Data System (ADS)

    Suryan, Abhilash; Kim, Dong Sun; Kim, Heuy Dong

    2010-04-01

    Large-capacity compressors in industrial plants and the compressors in gas turbine engines consume a considerable amount of power. The compression work is a strong function of the ambient air temperature. This increase in compression work presents a significant problem to utilities, generators and power producers when electric demands are high during the hot months. In many petrochemical process industries and gas turbine engines, the increase in compression work curtails plant output, demanding more electric power to drive the system. One way to counter this problem is to directly cool the inlet air. Inlet fogging is a popular means of cooling the inlet air to air compressors. In the present study, experiments have been performed to investigate the suitability of two-fluid nozzle for inlet fogging. Compressed air is used as the driving working gas for two-fluid nozzle and water at ambient conditions is dragged into the high-speed air jet, thus enabling the entrained water to be atomized in a very short distance from the exit of the two-fluid nozzle. The air supply pressure is varied between 2.0 and 5.0 bar and the water flow rate entrained is measured. The flow visualization and temperature and relative humidity measurements are carried out to specify the fogging characteristics of the two-fluid nozzle.

  17. Wave and Wind Effects on Inlet Circulation

    NASA Astrophysics Data System (ADS)

    Raubenheimer, B.; Wargula, A.; Orescanin, M. M.; Hopkins, J.; Elgar, S.

    2014-12-01

    Observations and numerical simulations of the water circulation and morphological change in two separate, well-mixed inlets will be compared with each other. Tides, winds, waves, and currents were measured from May 1 to 28, 2012 in and near New River Inlet, NC. Offshore significant wave heights were 0 to 3 m, and wind speeds ranged from 0 to 16 m/s. The long, narrow inlet is about 1000 m wide where it opens onto the ebb shoal, narrows to 100 m wide about 1000 m inland, and connects to the Intracoastal Waterway (which connects to additional ocean inlets about 12 and 36 km north and south, respectively) about 3000 m inland. Tides in the inlet are progressive and inlet flows are in phase with water depths. Measurements also were collected during the summers of 2011-2014, including during Hurricanes Irene and Sandy (offshore significant wave heights > 5 m and winds > 15 m/s), in Katama Bay, MA, which connects to Vineyard Sound via Edgartown Channel and to the Atlantic Ocean via Katama Inlet. During this period, Katama Inlet migrated east about 1000 m, narrowed from 400 to 100 m wide, changed depth from 7 to 2 m, and lengthened from 200 to 1000 m. Tidal flows in Katama Inlet are forced by sea level gradients resulting from the 3-hr phase lag between tides in Vineyard Sound and the Atlantic Ocean. Analyses of the momentum balances suggest that waves drive flows into the mouths of the inlets during storms. The timing of the storms relative to ebb and flood, and wind effects, may affect the discharge and sediment transport through the inlet. Winds and waves also drive alongshore flows on the ebb shoals. Lateral flows at bends in New River Inlet, which may be important to the along-inlet transfer of momentum and to mixing, are affected by winds. The importance of connections to additional inlets in multi-inlet systems will be discussed. Funded by ONR, ASD(R&E), NSF, Sea Grant, and NDSEG.

  18. Experimental, water droplet impingement data on two-dimensional airfoils, axisymmetric inlet and Boeing 737-300 engine inlet

    NASA Technical Reports Server (NTRS)

    Papadakis, M.; Elangovan, E.; Freund, G. A., Jr.; Breer, M. D.

    1987-01-01

    An experimental method has been developed to determine the droplet impingement characteristics on two- and three-dimensional bodies. The experimental results provide the essential droplet impingement data required to validate particle trajectory codes, used in aircraft icing analyses and engine inlet particle separator analyses. A body whose water droplet impingement characteristics are required is covered at strategic locations by thin strips of moisture absorbing (blotter) paper, and then exposed to an air stream containing a dyed-water spray cloud. Water droplet impingement data are extracted from the dyed blotter strips, by measuring the optical reflectance of the dye deposit on the strips, using an automated reflectometer. Impingement efficiency data obtained for a NACA 65(2)015 airfoil section, a supercritical airfoil section, and Being 737-300 and axisymmetric inlet models are presented in this paper.

  19. Internal Shock Interactions in Propulsion/Airframe Integrated Three-Dimensional Sidewall Compression Scramjet Inlets

    NASA Technical Reports Server (NTRS)

    Holland, Scott D.; Perkins, John N.

    1992-01-01

    The advantages and design requirements of propulsion/airframe integration for high Mach number flight have led to extensive study of the three-dimensional sidewall compression scramjet inlet in recent years. Recent research publications have indicated testing over a broad range of Mach number (2 to 18) in a variety of test gases, such as air, helium, and tetrafluoromethane. Multiple experimental techniques have been employed to obtain detailed internal shock interaction data, performance data, and inlet starting limits. Computational fluid dynamics has been effectively used for preliminary parametric studies as well as in parallel with experiments to aid in the explanation of unusual or unexpected flow phenomena. Inlets of this genre afford a relatively simple, generic geometry while producing a highly complex, three-dimensional flow field dominated by shock/shock and shock/boundary layer interactions. While the importance of the viscous effects in high speed inlet interactions is recognized, the present work addresses in a parametric fashion the inviscid effects of leading edge sweep, sidewall compression, and inflow Mach number on the internal shock structure in terms of inlet compression and mass capture. In the process, the source of the of the Mach number invariance with leading edge sweep for a constant sidewall compression class of inlet is identified, and a previously undocumented spillage phenomenon in a constant effective wedge angle class of inlets is discussed.

  20. 33 CFR 117.757 - Townsend Inlet.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 1 2014-07-01 2014-07-01 false Townsend Inlet. 117.757 Section 117.757 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements New Jersey § 117.757 Townsend Inlet. The draw...

  1. 33 CFR 117.757 - Townsend Inlet.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 1 2011-07-01 2011-07-01 false Townsend Inlet. 117.757 Section 117.757 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements New Jersey § 117.757 Townsend Inlet. The draw...

  2. 33 CFR 117.757 - Townsend Inlet.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 1 2013-07-01 2013-07-01 false Townsend Inlet. 117.757 Section 117.757 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements New Jersey § 117.757 Townsend Inlet. The draw...

  3. 33 CFR 117.714 - Corson Inlet.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 1 2011-07-01 2011-07-01 false Corson Inlet. 117.714 Section 117.714 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements New Jersey § 117.714 Corson Inlet. The draw of the Corson...

  4. 33 CFR 117.757 - Townsend Inlet.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 1 2012-07-01 2012-07-01 false Townsend Inlet. 117.757 Section 117.757 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements New Jersey § 117.757 Townsend Inlet. The draw...

  5. 33 CFR 117.714 - Corson Inlet.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 1 2013-07-01 2013-07-01 false Corson Inlet. 117.714 Section 117.714 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements New Jersey § 117.714 Corson Inlet. The draw of the Corson...

  6. 33 CFR 117.714 - Corson Inlet.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Corson Inlet. 117.714 Section 117.714 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements New Jersey § 117.714 Corson Inlet. The draw of the Corson...

  7. 33 CFR 117.714 - Corson Inlet.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 1 2014-07-01 2014-07-01 false Corson Inlet. 117.714 Section 117.714 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements New Jersey § 117.714 Corson Inlet. The draw of the Corson...

  8. 33 CFR 117.714 - Corson Inlet.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 1 2012-07-01 2012-07-01 false Corson Inlet. 117.714 Section 117.714 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements New Jersey § 117.714 Corson Inlet. The draw of the Corson...

  9. 33 CFR 117.757 - Townsend Inlet.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Townsend Inlet. 117.757 Section 117.757 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements New Jersey § 117.757 Townsend Inlet. The draw...

  10. External-Compression Supersonic Inlet Design Code

    NASA Technical Reports Server (NTRS)

    Slater, John W.

    2011-01-01

    A computer code named SUPIN has been developed to perform aerodynamic design and analysis of external-compression, supersonic inlets. The baseline set of inlets include axisymmetric pitot, two-dimensional single-duct, axisymmetric outward-turning, and two-dimensional bifurcated-duct inlets. The aerodynamic methods are based on low-fidelity analytical and numerical procedures. The geometric methods are based on planar geometry elements. SUPIN has three modes of operation: 1) generate the inlet geometry from a explicit set of geometry information, 2) size and design the inlet geometry and analyze the aerodynamic performance, and 3) compute the aerodynamic performance of a specified inlet geometry. The aerodynamic performance quantities includes inlet flow rates, total pressure recovery, and drag. The geometry output from SUPIN includes inlet dimensions, cross-sectional areas, coordinates of planar profiles, and surface grids suitable for input to grid generators for analysis by computational fluid dynamics (CFD) methods. The input data file for SUPIN and the output file from SUPIN are text (ASCII) files. The surface grid files are output as formatted Plot3D or stereolithography (STL) files. SUPIN executes in batch mode and is available as a Microsoft Windows executable and Fortran95 source code with a makefile for Linux.

  11. Electrically heated particulate matter filter with recessed inlet end plugs

    DOEpatents

    Gonze, Eugene V [Pinckney, MI; Ament, Frank [Troy, MI

    2012-02-21

    A particulate matter (PM) filter includes filter walls having inlet ends and outlet ends. First adjacent pairs of the filter walls define inlet channels. Second adjacent pairs of the filter walls define outlet channels. Outlet end plugs are arranged in the inlet channels adjacent to the output ends. Inlet end plugs arranged in the outlet channels spaced from the inlet ends.

  12. Abrasion resistant heat pipe

    DOEpatents

    Ernst, D.M.

    1984-10-23

    A specially constructed heat pipe is described for use in fluidized bed combustors. Two distinct coatings are spray coated onto a heat pipe casing constructed of low thermal expansion metal, each coating serving a different purpose. The first coating forms aluminum oxide to prevent hydrogen permeation into the heat pipe casing, and the second coating contains stabilized zirconium oxide to provide abrasion resistance while not substantially affecting the heat transfer characteristics of the system.

  13. Abrasion resistant heat pipe

    DOEpatents

    Ernst, Donald M.

    1984-10-23

    A specially constructed heat pipe for use in fluidized bed combustors. Two distinct coatings are spray coated onto a heat pipe casing constructed of low thermal expansion metal, each coating serving a different purpose. The first coating forms aluminum oxide to prevent hydrogen permeation into the heat pipe casing, and the second coating contains stabilized zirconium oxide to provide abrasion resistance while not substantially affecting the heat transfer characteristics of the system.

  14. Introduction to Heat Pipes

    NASA Technical Reports Server (NTRS)

    Ku, Jentung

    2015-01-01

    This is the presentation file for the short course Introduction to Heat Pipes, to be conducted at the 2015 Thermal Fluids and Analysis Workshop, August 3-7, 2015, Silver Spring, Maryland. NCTS 21070-15. Course Description: This course will present operating principles of the heat pipe with emphases on the underlying physical processes and requirements of pressure and energy balance. Performance characterizations and design considerations of the heat pipe will be highlighted. Guidelines for thermal engineers in the selection of heat pipes as part of the spacecraft thermal control system, testing methodology, and analytical modeling will also be discussed.

  15. Heat Pipe Materials Compatibility

    NASA Technical Reports Server (NTRS)

    Eninger, J. E.; Fleischman, G. L.; Luedke, E. E.

    1976-01-01

    An experimental program to evaluate noncondensable gas generation in ammonia heat pipes was completed. A total of 37 heat pipes made of aluminum, stainless steel and combinations of these materials were processed by various techniques, operated at different temperatures and tested at low temperature to quantitatively determine gas generation rates. In order of increasing stability are aluminum/stainless combination, all aluminum and all stainless heat pipes. One interesting result is the identification of intentionally introduced water in the ammonia during a reflux step as a means of surface passivation to reduce gas generation in stainless-steel/aluminum heat pipes.

  16. External artery heat pipe

    NASA Technical Reports Server (NTRS)

    Gernert, Nelson J. (Inventor); Ernst, Donald M. (Inventor); Shaubach, Robert M. (Inventor)

    1989-01-01

    An improved heat pipe with an external artery. The longitudinal slot in the heat pipe wall which interconnects the heat pipe vapor space with the external artery is completely filled with sintered wick material and the wall of the external artery is also covered with sintered wick material. This added wick structure assures that the external artery will continue to feed liquid to the heat pipe evaporator even if a vapor bubble forms within and would otherwise block the liquid transport function of the external artery.

  17. Pipe crawler apparatus

    DOEpatents

    Hovis, Gregory L.; Erickson, Scott A.; Blackmon, Bruce L.

    2002-01-01

    A pipe crawler apparatus particularly useful for 3-inch and 4-inch diameter pipes is provided. The pipe crawler apparatus uses a gripping apparatus in which a free end of a piston rod is modified with a bearing retaining groove. Bearings, placed within the groove, are directed against a camming surface of three respective pivoting support members. The non-pivoting ends of the support members carry a foot-like gripping member that, upon pivoting of the support member, engages the interior wall of the pipe.

  18. Heat Pipe Planets

    NASA Technical Reports Server (NTRS)

    Moore, William B.; Simon, Justin I.; Webb, A. Alexander G.

    2014-01-01

    When volcanism dominates heat transport, a terrestrial body enters a heat-pipe mode, in which hot magma moves through the lithosphere in narrow channels. Even at high heat flow, a heat-pipe planet develops a thick, cold, downwards-advecting lithosphere dominated by (ultra-)mafic flows and contractional deformation at the surface. Heat-pipes are an important feature of terrestrial planets at high heat flow, as illustrated by Io. Evidence for their operation early in Earth's history suggests that all terrestrial bodies should experience an episode of heat-pipe cooling early in their histories.

  19. Internal pipe attachment mechanism

    DOEpatents

    Bast, R.M.; Chesnut, D.A.; Henning, C.D.; Lennon, J.P.; Pastrnak, J.W.; Smith, J.A.

    1994-12-13

    An attachment mechanism is described for repairing or extending fluid carrying pipes, casings, conduits, etc. utilizing one-way motion of spring tempered fingers to provide a mechanical connection between the attachment mechanism and the pipe. The spring tempered fingers flex to permit insertion into a pipe to a desired insertion depth. The mechanical connection is accomplished by reversing the insertion motion and the mechanical leverage in the fingers forces them outwardly against the inner wall of the pipe. A seal is generated by crushing a sealing assembly by the action of setting the mechanical connection. 6 figures.

  20. Internal pipe attachment mechanism

    DOEpatents

    Bast, Richard M.; Chesnut, Dwayne A.; Henning, Carl D.; Lennon, Joseph P.; Pastrnak, John W.; Smith, Joseph A.

    1994-01-01

    An attachment mechanism for repairing or extending fluid carrying pipes, casings, conduits, etc. utilizing one-way motion of spring tempered fingers to provide a mechanical connection between the attachment mechanism and the pipe. The spring tempered fingers flex to permit insertion into a pipe to a desired insertion depth. The mechanical connection is accomplished by reversing the insertion motion and the mechanical leverage in the fingers forces them outwardly against the inner wall of the pipe. A seal is generated by crushing a sealing assembly by the action of setting the mechanical connection.

  1. Effects of out-of-plane double bent pipe on ultrasonic flow metering

    NASA Astrophysics Data System (ADS)

    Treenuson, Weerachon; Tsuzuki, Nobuyoshi; Kikura, Hiroshige; Wada, Sanehiro

    2014-06-01

    Ultrasonic Velocity Profile (UVP) method can be applied and succeeded for complicated flow as short inlet length from the double bent pipe. However, the flow of out-of-plane double bent pipe is more complicated and also more difficult to measure the highly accurate flowrate compare to in-plane double bent pipe. To solve this difficultly, the precise three-dimensional velocity profile forming is necessary. Multiple measurement lines are investigated for the out of plane double bent pipe to form the three-dimensional velocity profile. Moreover, the multiple measurement lines ultrasonic flow metering needs to optimize the number of measurement lines. In addition, the distance from the outlet to the measurement point as inlet length is also important. Therefore, the aims of this study are both estimate the optimal number of measurement lines and find out the minimum inlet length to measure the accurate flowrate on the out-of-plane double bent pipe by using a sampling transducers rating estimation method with signal processing technique. The minimization of the inlet length was started from 3 D, 4 D and 5 D. The estimation of optimal number of measurement lines was executed in the condition of Re~40,000. The out-of-plane double bent pipe was spread the out-of- plane angle at 0°, 8° and 16°. In this study, the circumferential velocity profiles are reconstructed from many velocity profiles measured around the center of pipe using single measurement lines. These circumferential velocity profiles come as the form of wave. Fourier Transform technique (FT) changes the waveform data to design the number of measurement lines by using sampling rate theory.

  2. Analysis of Porous Media as Inlet Concept for Rotating Detonation Engines

    NASA Astrophysics Data System (ADS)

    Grogan, Kevin; Ihme, Matthias; Department of Mechanical Engineering Team

    2016-11-01

    Rotating detonation engines combust reactive gas mixtures with a high-speed, annularly-propagating detonation wave, which provides many advantages including a stagnation pressure gain and a compact, lightweight design. However, the optimal design of the inlet to the combustion chamber inlet is a moot topic since improper design can significantly reduce detonability and increase pressure losses. The highly diffusive properties of porous media could make it an ideal material to prevent the flashback of the detonation wave and therefore, allow the inlet gas to be premixed. Motivated by this potential, this work employs simulation to evaluate the application of porous media to the inlet of a rotating detonation engine as a novel means to stabilize a detonation wave while reducing the pressure losses incurred by non-ideal mixing strategies. Department of the Air Force.

  3. The Unsteady Response of an Axial Flow Turbo-Machinery Rotor to Inlet Flow Distortions.

    DTIC Science & Technology

    1978-10-12

    the rotor inflow velocity. Distorted inlet flow is a very realistic and prevalent problem in jet air - craft engines, and the consequences of...Turbomachinery In designing the blading of a compressor or turbine, the air flow is assumed to be steady. The existence of a uniform, steady flow is...surface of the air - k- foil. When this occurs in a compressor, surge can occur. Surge will result in very large fluctuating forces on the blades which

  4. Water temperature effect on upward air-water flow in a vertical pipe: Local measurements database using four-sensor conductivity probes and LDA

    NASA Astrophysics Data System (ADS)

    Monrós-Andreu, G.; Chiva, S.; Martínez-Cuenca, R.; Torró, S.; Juliá, J. E.; Hernández, L.; Mondragón, R.

    2013-04-01

    Experimental work was carried out to study the effects of temperature variation in bubbly, bubbly to slug transition. Experiments were carried out in an upward air-water flow configuration. Four sensor conductivity probes and LDA techniques was used together for the measurement of bubble parameters. The aim of this paper is to provide a bubble parameter experimental database using four-sensor conductivity probes and LDA technique for upward air-water flow at different temperatures and also show transition effect in different temperatures under the boiling point.

  5. The CoLaPipe--the new Cottbus large pipe test facility at Brandenburg University of Technology Cottbus-Senftenberg.

    PubMed

    König, Franziska; Zanoun, El-Sayed; Öngüner, Emir; Egbers, Christoph

    2014-07-01

    The CoLaPipe is a novel test facility at the Department of Aerodynamics and Fluid Mechanics, Brandenburg University of Technology Cottbus-Senftenberg (BTU Cottbus-Senftenberg), set up to investigate fully developed pipe flow at high Reynolds numbers (Re(m) ⩽ 1.5 × 10(6)). The design of the CoLaPipe is closed-return with two available test sections providing a length-to-diameter ratio of L/D = 148 and L/D = 79. Within this work, we introduce the CoLaPipe and describe the various components in detail, i.e., the settling chamber, the inlet contraction, the blower, bends, and diffusers as well as the cooling system. A special feature is the numerically optimized contraction design. The applications of different measuring techniques such as hot-wire anemometry and static pressure measurements to quantitatively evaluate the mean flow characteristics and turbulence statistics are discussed as well. In addition, capabilities and limitations of available and new pipe flow facilities are presented and reconsidered based on their length-to-diameter ratio, the achieved Reynolds numbers, and the resulting spatial resolution. Here, the focus is on the facility design, the presentation of some basic characteristics, and its contribution to a reviewed list of specific questions still arising, e.g., scaling and structural behavior of turbulent pipe flow as well as the influence of the development length on turbulence investigations.

  6. Generation of Turbulent Inflow Conditions for Pipe Flow via an Annular Ribbed Turbulator

    NASA Astrophysics Data System (ADS)

    Moallemi, Nima; Brinkerhoff, Joshua

    2016-11-01

    The generation of turbulent inflow conditions adds significant computational expense to direct numerical simulations (DNS) of turbulent pipe flows. Typical approaches involve introducing boxes of isotropic turbulence to the velocity field at the inlet of the pipe. In the present study, an alternative method is proposed that incurs a lower computational cost and allows the anisotropy observed in pipe turbulence to be physically captured. The method is based on a periodic DNS of a ribbed turbulator upstream of the inlet boundary of the pipe. The Reynolds number based on the bulk velocity and pipe diameter is 5300 and the blockage ratio (BR) is 0.06 based on the rib height and pipe diameter. The pitch ratio is defined as the ratio of rib streamwise spacing to rib height and is varied between 1.7 and 5.0. The generation of turbulent flow structures downstream of the ribbed turbulator are identified and discussed. Suitability of this method for accurate representation of turbulent inflow conditions is assessed through comparison of the turbulent mean properties, fluctuations, Reynolds stress profiles, and spectra with published pipe flow DNS studies. The DNS results achieve excellent agreement with the numerical and experimental data available in the literature.

  7. Plasma control of shock wave configuration in off-design mode of M = 2 inlet

    NASA Astrophysics Data System (ADS)

    Falempin, Francois; Firsov, Alexander A.; Yarantsev, Dmitry A.; Goldfeld, Marat A.; Timofeev, Konstantin; Leonov, Sergey B.

    2015-03-01

    The objective of this work was to study the steering effect of a weakly ionized plasma on a supersonic flow structure in a two-dimensional aerodynamic configuration with a three-shock compression ramp in an off-design operational mode. Experiments were performed in wind tunnel T-313 of ITAM SB RAS, with the model air inlet designed for operation at a flow of Mach number M = 2. The inlet was tested at M = 2, 2.5, and 3 and with Re = (25-36) × 106/m and an angle of attack AoA = 0°, 5°, and 8°. For the regulation of the inlet characteristics, a plasma generator with electrical power W pl = 2-10 kW was flush-mounted upstream of the compression ramp. A significant plasma effect on the shock configuration at the inlet and on the flow parameters after air compression is considered. It is shown that the main shock wave angle is controllable by means of the plasma power magnitude and, therefore, can be accurately adjusted to the cowl lip of an inlet with a fixed geometry. An additional plasma effect has been demonstrated through a notable increase in the pressure recovery coefficient in a flowpass extension behind the inlet because of an nearly isentropic pattern of flow compression with the plasma turned on. Numerical simulation brings out the details of 3D distribution of the flow structure and parameters throughout the model at thermal energy deposition in inlet near the compression surfaces. We conclude that the plasma-based technique may be a feasible method for expanding supersonic inlet operational limits.

  8. Shock Positioning Controls Designs for a Supersonic Inlet

    NASA Technical Reports Server (NTRS)

    Kopasakis, George; Connolly, Joseph W.

    2010-01-01

    Under the NASA Fundamental Aeronautics Program, the Supersonics Project is working to overcome the obstacles to supersonic commercial flight. The supersonic inlet design that is utilized to efficiently compress the incoming air and deliver it to the engine has many design challenges. Among those challenges is the shock positioning of internal compression inlets, which requires active control in order to maintain performance and to prevent inlet unstarts due to upstream (freestream) and downstream (engine) disturbances. In this paper a novel feedback control technique is presented, which emphasizes disturbance attenuation among other control performance criteria, while it ties the speed of the actuation system(s) to the design of the controller. In this design, the desired performance specifications for the overall control system are used to design the closed loop gain of the feedback controller and then, knowing the transfer function of the plant, the controller is calculated to achieve this performance. The innovation is that this design procedure is methodical and allows maximization of the performance of the designed control system with respect to actuator rates, while the stability of the calculated controller is guaranteed.

  9. Research on Supersonic Inlet Bleed

    NASA Technical Reports Server (NTRS)

    Davis, David O.; Vyas, Manan A.; Slater, John W.

    2012-01-01

    Phase I data results of the Fundamental Inlet Bleed Experiments project at NASA Glenn Research Center (GRC) are presented which include flow coefficient results for two single-hole boundary-layer bleed configurations. The bleed configurations tested are round holes at inclination angles of 90deg and 20deg both having length-to-diameter ratios of 2.0. Results were obtained at freestream Mach numbers of 1.33, 1.62, 1.98, 2.46, and 2.92 and unit Reynolds numbers of 0.984, 1.89, and 2.46 10(exp 7)/m. Approach boundary-layer data are presented for each flow condition and the flow coefficient results are compared to existing multi-hole data obtained under similar conditions. For the 90deg hole, the single and multi-hole distributions agree fairly well with the exception that under supercritical operation, the multi-hole data chokes at higher flow coefficient levels. This behavior is also observed for the 20deg hole but to a lesser extent. The 20deg hole also shows a markedly different characteristic at subcritical operation. Also presented are preliminary results of a Computational Fluid Dynamics (CFD) analysis of both configurations at the Mach 1.33 and a unit Reynolds number of 2.46 10(exp 7)/m. Comparison of the results shows the agreement to be very good.

  10. Piping Effects on the Heat Transfer Characteristics of an Evacuated Tubular Solar Collector

    NASA Astrophysics Data System (ADS)

    Saito, Akio; Miyazawa, Nobuyuki

    Effects on the heat transfer characteristics of a vacuum type solar collector system by connecting piping sections were discussed experimentally and analytically. Experiments were carried out under various solar radiation intensities, water flow rates, inlet water temperatures, periods of the solar intensity fluctuations and the insulating specifications for the piping section. Simulations were also performed by the finite difference calculations which were proved to agree well with the experimental results. As the results, it was found that the slight water temperature decrease at the entrance of the collector, by connecting the piping section, did not affect the collector efficiency seriously, although the whole collector plate temperature was lowered. It was also found that the heat loss from the collector plate to the pipe was negligible, if the piping section was insulated properly, and the effects appeared only in the limited edge sections of the collector plate, lowering the plate temperature.

  11. Heat pipe methanator

    DOEpatents

    Ranken, William A.; Kemme, Joseph E.

    1976-07-27

    A heat pipe methanator for converting coal gas to methane. Gravity return heat pipes are employed to remove the heat of reaction from the methanation promoting catalyst, transmitting a portion of this heat to an incoming gas pre-heat section and delivering the remainder to a steam generating heat exchanger.

  12. Splayed mirror light pipes

    SciTech Connect

    Swift, P.D.

    2010-02-15

    An expression is given for the transmission of the rectangular-section mirror light pipe. The expression is used to model throughputs for simulated solar conditions over a calender year. It is found that the splaying of a mirror light pipe results in a significant increase in throughputs particularly in winter months. (author)

  13. These Pipes Are "Happening"

    ERIC Educational Resources Information Center

    Skophammer, Karen

    2010-01-01

    The author is blessed with having the water pipes for the school system in her office. In this article, the author describes how the breaking of the pipes had led to a very worthwhile art experience for her students. They practiced contour and shaded drawing techniques, reviewed patterns and color theory, and used their reasoning skills--all while…

  14. Boundary-Layer-Ingesting Inlet Flow Control

    NASA Technical Reports Server (NTRS)

    Owens, Lewis R.; Allan, Brian G.; Gorton, Susan A.

    2006-01-01

    This paper gives an overview of a research study conducted in support of the small-scale demonstration of an active flow control system for a boundary-layer-ingesting (BLI) inlet. The effectiveness of active flow control in reducing engine inlet circumferential distortion was assessed using a 2.5% scale model of a 35% boundary-layer-ingesting flush-mounted, offset, diffusing inlet. This experiment was conducted in the NASA Langley 0.3-meter Transonic Cryogenic Tunnel at flight Mach numbers with a model inlet specifically designed for this type of testing. High mass flow actuators controlled the flow through distributed control jets providing the active flow control. A vortex generator point design configuration was also tested for comparison purposes and to provide a means to examine a hybrid vortex generator and control jets configuration. Measurements were made of the onset boundary layer, the duct surface static pressures, and the mass flow through the duct and the actuators. The distortion and pressure recovery were determined by 40 total pressure measurements on 8 rake arms each separated by 45 degrees and were located at the aerodynamic interface plane. The test matrix was limited to a maximum free-stream Mach number of 0.85 with scaled mass flows through the inlet for that condition. The data show that the flow control jets alone can reduce circumferential distortion (DPCP(sub avg)) from 0.055 to about 0.015 using about 2.5% of inlet mass flow. The vortex generators also reduced the circumferential distortion from 0.055 to 0.010 near the inlet mass flow design point. Lower inlet mass flow settings with the vortex generator configuration produced higher distortion levels that were reduced to acceptable levels using a hybrid vortex generator/control jets configuration that required less than 1% of the inlet mass flow.

  15. Boundary-Layer-Ingesting Inlet Flow Control

    NASA Technical Reports Server (NTRS)

    Owens, Lewis R.; Allan, Brian G.; Gorton, Susan A.

    2006-01-01

    This paper gives an overview of a research study conducted in support of the small-scale demonstration of an active flow control system for a boundary-layer-ingesting (BLI) inlet. The effectiveness of active flow control in reducing engine inlet circumferential distortion was assessed using a 2.5% scale model of a 35% boundary-layer-ingesting flush-mounted, offset, diffusing inlet. This experiment was conducted in the NASA Langley 0.3-meter Transonic Cryogenic Tunnel at flight Mach numbers with a model inlet specifically designed for this type of testing. High mass flow actuators controlled the flow through distributed control jets providing the active flow control. A vortex generator point design configuration was also tested for comparison purposes and to provide a means to examine a hybrid vortex generator and control jets configuration. Measurements were made of the onset boundary layer, the duct surface static pressures, and the mass flow through the duct and the actuators. The distortion and pressure recovery were determined by 40 total pressure measurements on 8 rake arms each separated by 45 degrees and were located at the aerodynamic interface plane. The test matrix was limited to a maximum free-stream Mach number of 0.85 with scaled mass flows through the inlet for that condition. The data show that the flow control jets alone can reduce circumferential distortion (DPCPavg) from 0.055 to about 0.015 using about 2.5% of inlet mass flow. The vortex generators also reduced the circumferential distortion from 0.055 to 0.010 near the inlet mass flow design point. Lower inlet mass flow settings with the vortex generator configuration produced higher distortion levels that were reduced to acceptable levels using a hybrid vortex generator/control jets configuration that required less than 1% of the inlet mass flow.

  16. Alpha characterization inside pipes using ion-transport technology

    NASA Astrophysics Data System (ADS)

    Rojas, S. P.; Rawool-Sullivan, M. W.; Williams, K. G.; Vaccarella, J. A.

    Many DOE facilities have several miles of waste pipe systems that are internally contaminated with various and often undetermined radio nuclides. Unfortunately, currently acceptable alpha detection technologies are inefficient, time consuming, and do not address the problems presented by small diameter or curved pipes. In general, the problem of detecting alpha contamination on the inside surface of pipes is complicated by the fact that alphas do not penetrate the pipe walls. Unlike their conventional counterparts, alpha detectors based on ion transport technology sense alpha particles by collecting the ions created in ambient air as the particle loses its kinetic energy. The ions inside the pipe are transported by a fan-generated air current to an electrode inside the detector, which is attached to one end of the pipe. The collected charge at the electrode is proportional to the number of ions created inside the pipe, which in turn is proportional to the number of alphas emitted. Typically, monitoring for alpha contamination inside pipes or ductwork involves disrupting the operation to access as much surface area as possible for standard alpha monitoring. The detector based on ion transport technology effectively minimizes such disruption and in many circumstances will allow for in situ monitoring of a system that might otherwise not be practically accessible to standard methods.

  17. Wind- and Tide-Driven Cross-Inlet Circulation at New River Inlet, NC

    NASA Astrophysics Data System (ADS)

    Wargula, A.; Raubenheimer, B.; Elgar, S.

    2014-12-01

    The importance of cross-channel wind forcing to inlet circulation is examined using observations of winds, waves, water levels, and currents collected in and near New River Inlet, NC during May 2012. Although the direct effect of local wind forcing may be neglected in the subtidal along-inlet momentum balance, which is dominated by the pressure gradient, wave radiation stress gradient, and bottom friction, cross-inlet winds may have a significant effect on along-inlet dynamics by driving cross-inlet flows (approximately 0.1 to 0.3 m/s), which can mix lateral and vertical gradients in momentum and water properties. New River Inlet is 1000 m wide at the mouth and tapers to 100 m wide about 1000 m away from the mouth after two sharp 90° bends. Five colocated pressure gages and current profilers were deployed from the shallow (2-3 m water depth) ebb shoal outside the mouth through the deep (5-10 m depth) inlet channel to 200 m beyond the first 90° bend. The inlet is well mixed, and along-inlet tidal currents ranged from +/- 1.5 m/s, offshore significant wave heights from 0.5 to 2.5 m, and wind speeds from 0 to 16 m/s. Time series of currents and winds were lowpass-filtered to examine subtidal wind effects. At the first 90° bend, both surface and bottom cross-inlet flows were correlated (r2 = 0.6) with cross-inlet wind velocity. On the shallow ebb shoal, the cross-inlet flows also were correlated with cross-inlet wind velocity (r2 = 0.6). Cross-inlet flows exhibited a two-layer response to the wind inside the inlet and a depth-uniform response outside the mouth. The observations will be used to examine the momentum balance governing temporal and spatial variations in cross-inlet wind effects on inlet circulation. Funding provided by the Office of Naval Research, the Assistant Secretary of Defense for Research and Engineering, and a National Defense Science and Engineering Graduate Fellowship.

  18. The monster sound pipe

    NASA Astrophysics Data System (ADS)

    Ruiz, Michael J.; Perkins, James

    2017-03-01

    Producing a deep bass tone by striking a large 3 m (10 ft) flexible corrugated drainage pipe immediately grabs student attention. The fundamental pitch of the corrugated tube is found to be a semitone lower than a non-corrugated smooth pipe of the same length. A video (https://youtu.be/FU7a9d7N60Y) of the demonstration is included, which illustrates how an Internet keyboard can be used to estimate the fundamental pitches of each pipe. Since both pipes have similar end corrections, the pitch discrepancy between the smooth pipe and drainage tube is due to the corrugations, which lower the speed of sound inside the flexible tube, dropping its pitch a semitone.

  19. The Origin of Inlet Buzz in a Mach 1.7 Low Boom Inlet Design

    NASA Technical Reports Server (NTRS)

    Anderson, Bernhard H.; Weir, Lois

    2014-01-01

    Supersonic inlets with external compression, having a good level performance at the critical operating point, exhibit a marked instability of the flow in some subcritical operation below a critical value of the capture mass flow ratio. This takes the form of severe oscillations of the shock system, commonly known as "buzz". The underlying purpose of this study is to indicate how Detached Eddy Simulation (DES) analysis of supersonic inlets will alter how we envision unsteady inlet aerodynamics, particularly inlet buzz. Presented in this paper is a discussion regarding the physical explanation underlying inlet buzz as indicated by DES analysis. It is the normal shock wave boundary layer separation along the spike surface which reduces the capture mass flow that is the controlling mechanism which determines the onset of inlet buzz, and it is the aerodynamic characteristics of a choked nozzle that provide the feedback mechanism that sustains the buzz cycle by imposing a fixed mean corrected inlet weight flow. Comparisons between the DES analysis of the Lockheed Martin Corporation (LMCO) N+2 inlet and schlieren photographs taken during the test of the Gulfstream Large Scale Low Boom (LSLB) inlet in the NASA 8x6 ft. Supersonic Wind Tunnel (SWT) show a strong similarity both in turbulent flow field structure and shock wave formation during the buzz cycle. This demonstrates the value of DES analysis for the design and understanding of supersonic inlets.

  20. Gas Turbine Engine Inlet Wall Design

    NASA Technical Reports Server (NTRS)

    Florea, Razvan Virgil (Inventor); Matalanis, Claude G. (Inventor); Stucky, Mark B. (Inventor)

    2016-01-01

    A gas turbine engine has an inlet duct formed to have a shape with a first ellipse in one half and a second ellipse in a second half. The second half has an upstream most end which is smaller than the first ellipse. The inlet duct has a surface defining the second ellipse which curves away from the first ellipse, such that the second ellipse is larger at an intermediate location. The second ellipse is even larger at a downstream end of the inlet duct leading into a fan.

  1. Aeroacoustic performance of a scoop inlet

    NASA Technical Reports Server (NTRS)

    Abbott, J. M.

    1977-01-01

    Results of a low speed wind tunnel test program are presented which demonstrate the aerodynamic and acoustic performance of a scoop inlet. Engine noise that would normally propagate toward the ground is directed upward by the extended lower lip of the scoop inlet. In addition, more of the scoop airflow comes in from above the inlet than below, leading to relatively higher surface velocities on the upper lip and lower surface velocities on the lower lip. These lower velocities on the lower lip result in a higher attainable angle of attack before internal flow separation occurs.

  2. Boundary conditions for unsteady supersonic inlet analyses

    NASA Astrophysics Data System (ADS)

    Mayer, David W.; Paynter, Gerald C.

    1994-06-01

    New bleed and compressor face boundary conditions have been developed to improve the accuracy of unsteady supersonic inlet calculations. The new bleed boundary conditions relate changes in the bleed hole discharge coefficient to changes in the local flow conditions; the local bleed flow rate can more than double as a shock moves forward over a bleed band in response to inlet flow disturbances. The effects of inlet flow disturbances on the flow at the compressor face are represented more realistically with this new boundary condition than with traditional fixed static pressure or mass flow conditions.

  3. Heat pipe cooling of an aerospace foam mold manufacturing process

    SciTech Connect

    Hahn, D.R.; Feldman, K.T.; Marjon, P.L.

    1980-01-01

    A passive heat pipe cooling system was developed to cool a Bendix foam mold used to manufacture aerospace foam parts. The cooling system consists of ten copper-water heat pipes with cooling fins implanted into the aluminum mold and cooled by a domestic size fan blowing ambient air. The number and location of the heat pipes was determined to provide the most effective cooling and mold isothermalization based on experimental measurements of mold temperatures during the exothermic foaming process and from practical considerations of the mold geometry and use. Performance tests were cnducted on an individual heat pipe and on the ten heat pipes implanted in the mold. Both exothermic foam heating and internal electrical heat input were used in the experiments. The experimental test results indicate that the heat pipe cooling system with a fan is four to six times faster than free convection cooling of the mold with no heat pipes or fan and nearly twice as fast as cooling by the fan only. Similarly fast increases in mold heating time in the cure furnace could be realized if the heat pipes are used during this part of the production process. The heat pipes also cool hot spots in the mold and help isothermalize the mold so that better quality foam parts should be produced.

  4. Advanced Heat Pipes For Optical Applications

    NASA Astrophysics Data System (ADS)

    Shaubach, Robert M.; Eastman, G. Yale

    1984-12-01

    Heat pipes offer the potential of vibrationless cooling of optical surfaces while maintaining a high degree of temperature uniformity on the cooled surface. The objective of the present program is to develop and demonstrate prototype heat pipes for this application. The material of construction is silicon; the pqwer density range is 5 to 50 Watts/per square centimeter with a nominal objective of 30 W/cm2. This paper describes the first eighteen months of work, during which the contract goals were met. The program was carried out by Thermacore on Contract F33615-82-C-5127 for the Department of the Air Force, Aeronautical Systems Division, Wright-Patterson Air Force Base, Ohio. Dr. Alan K. Hopkins of the Materials Laboratory supplied technical supervision of the program for the Air Force.

  5. The Effect of the Channel Head on the Unsteady Pressure Pulsation Characteristics at the Inlet and Outlet of Reactor Coolant Pumps

    NASA Astrophysics Data System (ADS)

    Yun, Long; Junlian, Yin; Dezhong, Wang; Yaoyu, Hu

    2016-11-01

    In this paper, CFD approach was employed to analyse the inlet and outlet pressure pulsation characteristics of reactor coolant pumps with different inflows. The Reynolds- averaged Naiver-Stokes equations with the k-ɛ turbulence model were solved by the computational fluid dynamics software CFX to conduct the steady and unsteady numerical simulation. The numerical results of the straight pipe and channel head were validated with experimental data for the heads at different flow coefficients. In the nominal flow rate, the head of the pump with the channel head decreases by 1.19% when compared to the straight pipe. The channel head induces the inlet flow non-uniform, and the non-uniformity of the inflow induces the outlet flow of the pump with channel head different from that of the straight pipe. Meanwhile, the pressure pulsation signals are analysed using RMS, Standard Deviation and Peak-to-Peak Value method. At the points of the inlet and outlet, the pressure pulsation characteristics between the channel head and straight pipe are compared, and the difference is obviously. It is evident that the two different inflows of channel head and straight pipe have significant effect on the pump unsteady pressure pulsation. Finally, it is expected that the effects of non-uniform inflow on the pump performance and unsteady pressure pulsation are absolutely different from the uniform inflow. It is very important to provide accurate input conditions for the design and safety of the reactor.

  6. Varying duty operation of air-cooled condenser units

    NASA Astrophysics Data System (ADS)

    Milman, O. O.; Kondratev, A. V.; Ptakhin, A. V.; Dunaev, S. N.; Kirjukhin, A. V.

    2016-05-01

    Results of experimental investigations of operation modes of air-cooled condensers (ACC) under design and varying duty conditions are presented. ACCs with varying cooling airflow rates under constant heat load and with constant cooling airflow under varying heat load are examined. Diagrams of heat transfer coefficients and condensation pressures on the heat load and cooling airflow are obtained. It is found that, if the relative heat load is in the range from 0.6 to 1.0 of the nominal value, the ACC heat transfer coefficient varies insignificantly, unlike that of the water-cooled surface condensers. The results of the determination of "zero points" are given, i.e., the attainable pressure in air-cooled condensing units (ACCU), if there is no heat load for several values of working water temperature at the input of water-jet ejectors and liquid ring vacuum pump. The results of the experimental determination of atmospheric air suction into the ACC vacuum system. The effect of additional air suctions in the steam pipe on ACCU characteristics is analyzed. The thermal mapping of ACC heat exchange surfaces from the cooling air inlet is carried out. The dependence of the inefficient heat exchange zone on the additional air suction into the ACC vacuum system is given. It is shown that, if there is no additional air suction into the ACC vacuum system, the inefficient heat exchange zone is not located at the bottom of the first pass tubes, and their portion adjacent to the bottom steam pipe works efficiently. Design procedures for the ACC varying duty of capacitors are presented, and their adequacy for the ACCU varying duty estimation is analyzed.

  7. Compression-ignition Engine Performance at Altitudes and at Various Air Pressures and Temperatures

    NASA Technical Reports Server (NTRS)

    Moore, Charles S; Collins, John H

    1937-01-01

    Engine test results are presented for simulated altitude conditions. A displaced-piston combustion chamber on a 5- by 7-inch single cylinder compression-ignition engine operating at 2,000 r.p.m. was used. Inlet air temperature equivalent to standard altitudes up to 14,000 feet were obtained. Comparison between performance at altitude of the unsupercharged compression-ignition engine compared favorably with the carburetor engine. Analysis of the results for which the inlet air temperature, inlet air pressure, and inlet and exhaust pressure were varied indicates that engine performance cannot be reliably corrected on the basis of inlet air density or weight of air charge. Engine power increases with inlet air pressure and decreases with inlet air temperatures very nearly as straight line relations over a wide range of air-fuel ratios. Correction factors are given.

  8. The dynamics of axisymmetric swirling flows in a diverging or contracting circular pipe

    NASA Astrophysics Data System (ADS)

    Rusak, Zvi; Wang, Shixiao

    2009-11-01

    This paper describes a study of the effect of pipe divergence and contraction on the stability and breakdown of axisymmetric swirling flows in a long, finite-length, circular pipe. The work extends the theory of Wang & Rusak (1997). The approach is based on a rigorous analysis of the axisymmetric, steady and inviscid flow equations with non-periodic boundary conditions. The analysis firmly establishes the global bifurcation of flow states in the pipe (solutions of the Squire-Long PDE) by relating it to the bifurcation of solutions of the columnar flow problem (solutions of the resulting ODE) and using a new flow force relationship between the inlet and outlet states. This technique provides a simple, yet exact, method of analyzing the complex flow behavior including transitions from near-columnar vortex states to flow fields with large separation (stagnation) zones along the pipe centerline (breakdown states) or along the pipe wall (swirl induced wall separation). Bifurcation diagrams for base vortex models including the solid- body rotation and the Burgers vortex are presented. The stability characteristics of the various branches of solutions and the flow dynamics in the pipe under various perturbations are discussed. Results show that pipe divergence or contraction significantly modify the global flow behavior in a straight pipe and shed light on the effect of pipe geometry on the mechanism of vortex breakdown.

  9. The Peel Inlet-Harvey Estuary Study.

    ERIC Educational Resources Information Center

    Walker, Warren; Black, Ronald

    1979-01-01

    Describes how the department of physics of the Western Australian Institute of Technology (WAIT) has been involved in the Peel Inlet-Harvey Estuary study. An appendix which presents the departmental approach to curriculum matters is also included. (HM)

  10. Computational analysis of ramjet engine inlet interaction

    NASA Technical Reports Server (NTRS)

    Duncan, Beverly; Thomas, Scott

    1992-01-01

    A computational analysis of a ramjet engine at Mach 3.5 has been conducted and compared to results obtained experimentally. This study focuses on the behavior of the inlet both with and without combustor backpressure. Increased backpressure results in separation of the body side boundary layer and a resultant static pressure rise in the inlet throat region. The computational results compare well with the experimental data for static pressure distribution through the engine, inlet throat flow profiles, and mass capture. The computational analysis slightly underpredicts the thickness of the engine body surface boundary layer and the extent of the interaction caused by backpressure; however, the interaction is observed at approximately the same level of backpressure both experimentally and computationally. This study demonstrates the ability of two different Navier-Stokes codes, namely RPLUS and PARC, to calculate the flow features of this ramjet engine and to provide more detailed information on the process of inlet interaction and unstart.

  11. Noise suppression with high Mach number inlets

    NASA Technical Reports Server (NTRS)

    Lumsdaine, E.; Cherng, J. G.; Tag, I.

    1976-01-01

    Experimental results were obtained for two types of high Mach number inlets, one with a translating centerbody and a fixed geometry inlet (collapsing cowl) with no centerbody. The aerodynamic and acoustic performance of these inlets was examined. The effects of area ratio, length/diameter ratio, and lip geometry were among several parameters investigated. The translating centerbody type inlet was found to be superior to the collapsing cowl both acoustically and aerodynamically, particularly for area ratios greater than 1.5. Comparison of length/diameter ratio and area ratio effects on performance near choked flow showed the latter to be more significant. Also, greater high frequency noise attenuation was achieved by increasing Mach number from low to high subsonic values.

  12. Sample inlet tube for ion source

    DOEpatents

    Prior, David [Hermiston, OR; Price, John [Richland, WA; Bruce, Jim [Oceanside, CA

    2002-09-24

    An improved inlet tube is positioned within an aperture through the device to allow the passage of ions from the ion source, through the improved inlet tube, and into the interior of the device. The inlet tube is designed with a larger end and a smaller end wherein the larger end has a larger interior diameter than the interior diameter of the smaller end. The inlet tube is positioned within the aperture such that the larger end is pointed towards the ion source, to receive ions therefrom, and the smaller end is directed towards the interior of the device, to deliver the ions thereto. Preferably, the ion source utilized in the operation of the present invention is a standard electrospray ionization source. Similarly, the present invention finds particular utility in conjunction with analytical devices such as mass spectrometers.

  13. Small inlet optical panel and a method of making a small inlet optical panel

    DOEpatents

    Veligdan, James T.; Slobodin, David

    2001-01-01

    An optical panel having a small inlet, and a method of making a small inlet optical panel, are disclosed, which optical panel includes a individually coating, stacking, and cutting a first plurality of stacked optical waveguides to form an outlet face body with an outlet face, individually coating, stacking, and cutting a second plurality of stacked optical waveguides to form an inlet face body with an inlet face, and connecting an optical coupling element to the first plurality and to the second plurality, wherein the optical coupling element redirects light along a parallel axis of the inlet face to a parallel axis of the outlet face. In the preferred embodiment of the present invention, the inlet face is disposed obliquely with and askew from the outlet face.

  14. Effect of inlet disturbances on fan inlet noise during a static test

    NASA Technical Reports Server (NTRS)

    Bekofske, K. L.; Sheer, R. E., Jr.; Wang, J. C. F.

    1977-01-01

    Measurements of fan rotor inlet noise taken during static test situations are at variance with aircraft engine flight data. In particular, static tests generally yield a significantly higher tone at blade passage frequency than that measured during flight. To explain this discrepancy, the extent of the influence of inlet ground vortices and large-scale inlet turbulence on the forward-radiated fan noise measured at a static test facility was investigated. While such inlet disturbances were generated intentionally in an anechoic test chamber, far-field acoustic measurements and inlet flow-field hot-film mappings of a fan rotor were obtained. Experimental results indicate that the acoustic effect of such disturbances appears to be less severe for supersonic than for subsonic tip speeds. Further, a reverse flow that occurs on the exterior cowl in static test facilities appears to be an additional prime candidate for creating inlet disturbances and causing variance between flight and static acoustic data.

  15. Fluid dynamic modeling of junctions in internal combustion engine inlet and exhaust systems

    NASA Astrophysics Data System (ADS)

    Chalet, David; Chesse, Pascal

    2010-10-01

    The modeling of inlet and exhaust systems of internal combustion engine is very important in order to evaluate the engine performance. This paper presents new pressure losses models which can be included in a one dimensional engine simulation code. In a first part, a CFD analysis is made in order to show the importance of the density in the modeling approach. Then, the CFD code is used, as a numerical test bench, for the pressure losses models development. These coefficients depend on the geometrical characteristics of the junction and an experimental validation is made with the use of a shock tube test bench. All the models are then included in the engine simulation code of the laboratory. The numerical calculation of unsteady compressible flow, in each pipe of the inlet and exhaust systems, is made and the calculated engine torque is compared with experimental measurements.

  16. Inlet Processes at Eel Pond, Falmouth, Massachusetts.

    DTIC Science & Technology

    1984-10-01

    7 D -A147 548 INLET PROCESSES AT EEL POND FALMOUTH MRSS CHUSETi7 jV 1/2.COASTAL ENGINEERING RESEARCH CENTER YICKSBURG MS A E DEWRLL ET AL. OCT 84...42 c. Sediment Transport. ................... 42 d . Aerial Photograph: 21 November 1938. .......... 46 e. Aerial Photograph...Structural Changes to Inlet Hydraulics. ......... 59 c. Predicted Channel Stability .. .............. 69 d . Longshore Transport Estimates

  17. Circulation exchange patterns in Sinclair Inlet, Washington

    USGS Publications Warehouse

    Noble, Marlene A.; Rosenberger, Kurt J.; Paulson, Anthony J.; Gartner, Anne L.

    2013-01-01

    In 1994, the U.S. Geological Survey (USGS), in cooperation with the U.S. Navy, deployed three sets of moorings in Sinclair Inlet, which is a relatively small embayment on the western side of Puget Sound (fig. 1). This inlet is home to the Puget Sound Naval Shipyard. One purpose of the measurement program was to determine the transport pathways and fate of contaminants known to be present in Sinclair Inlet. Extensive descriptions of the program and the resultant information about contaminant pathways have been reported in Gartner and others (1998). This report primarily focused on the bottom boundary layer and the potential for resuspension and transport of sediments on the seabed in Sinclair Inlet as a result of tides and waves. Recently (2013), interest in transport pathways for suspended and dissolved materials in Sinclair Inlet has been rekindled. In particular, the USGS scientists in Washington and California have been asked to reexamine the datasets collected in the earlier study to refine not only our understanding of transport pathways through the inlet, but to determine how those transport pathways are affected by subtidal currents, local wind stress, and fresh water inputs. Because the prior study focused on the bottom boundary layer and not the water column, a reanalysis of the datasets could increase our understanding of the dynamic forces that drive transport within and through the inlet. However, the early datasets are limited in scope and a comprehensive understanding of these transport processes may require more extensive datasets or the development of a detailed numerical model of transport processes for the inlet, or both.

  18. Multiducted Inlet Combustor Research and Development.

    DTIC Science & Technology

    1982-10-01

    qualitative data from the multi-ducted inlet combustor configuration for flow analysis and matematical modeling purposes. The major portion of the support...data on multi-ducted inlet combustor configurations. These efforts will provide the information necessary to perform flow field analysis and aid in the...instrumentation, test program, data reduction, data presentation, flow field analysis and math modelling efforts, and conclusions and recommendations. SECTION 2

  19. Boundary conditions for unsteady supersonic inlet analyses

    NASA Astrophysics Data System (ADS)

    Mayer, David W.; Paynter, Gerald C.

    1994-06-01

    New bleed and compresor face boundary conditions have been developed to improve the accuracy of unsteady supersonic inlet calculations. The new bleed boundary condition relates changes in the bleed hole discharge coefficient to change the local flow conditions; the local bleed flow rate can more than double as a shock moves forward over a bleed band in response to inlet flow disturbances. The stability margin of the inlet is strongly dependent on the throat bleed configuration since the locally rapid increase in bleed flow has a stong effect on the motion of the normal shock. The new compressor face boundary condition accounts for changes in the unsteady flow conditions at the compressor face by specifying the compressor face corrected mass flow or Mach number either as a constant or as a linear function of the stagnation conditions. The effects of inlet flow disturbances on the flow at the compressor face are represented more realistically with this new boundary condition than with traditional fixed static pressure or mass flow conditions. Euler calculations of the dynamic response of an inlet flow to a flow disturbance at the compressor face with 20- and 90-deg throat bleed hole angles are reported. These results indicate that an extra margin of stability for the inlet is obtained with 90-deg bleed holes because the increase in bleed flow rate as the shock moves forward over a bleed is much larger for 90-deg holes than for 20-deg holes.

  20. Boundary-Layer-Ingesting Inlet Flow Control

    NASA Technical Reports Server (NTRS)

    Owens, Lewis R.; Allan, Brian G.; Gorton, Susan A.

    2008-01-01

    An experimental study was conducted to provide the first demonstration of an active flow control system for a flush-mounted inlet with significant boundary-layer-ingestion in transonic flow conditions. The effectiveness of the flow control in reducing the circumferential distortion at the engine fan-face location was assessed using a 2.5%-scale model of a boundary-layer-ingesting offset diffusing inlet. The inlet was flush mounted to the tunnel wall and ingested a large boundary layer with a boundary-layer-to-inlet height ratio of 35%. Different jet distribution patterns and jet mass flow rates were used in the inlet to control distortion. A vane configuration was also tested. Finally a hybrid vane/jet configuration was tested leveraging strengths of both types of devices. Measurements were made of the onset boundary layer, the duct surface static pressures, and the mass flow rates through the duct and the flow control actuators. The distortion and pressure recovery were measured at the aerodynamic interface plane. The data show that control jets and vanes reduce circumferential distortion to acceptable levels. The point-design vane configuration produced higher distortion levels at off-design settings. The hybrid vane/jet flow control configuration reduced the off-design distortion levels to acceptable ones and used less than 0.5% of the inlet mass flow to supply the jets.

  1. Investigation of Unsteady Flow Interaction Between an Ultra-Compact Inlet and a Transonic Fan

    NASA Technical Reports Server (NTRS)

    Hah, Chunill; Rabe, Douglas; Scribben, Angie

    2015-01-01

    In the present study, unsteady flow interaction between an ultra-compact inlet and a transonic fan stage is investigated. Future combat aircraft require ultra-compact inlet ducts as part of an integrated, advanced propulsion system to improve air vehicle capability and effectiveness to meet future mission needs. The main purpose of the study is to advance the current understanding of the flow interaction between two different ultra-compact inlets and a transonic fan for future design applications. Both URANS and LES approaches are used to calculate the unsteady flow field and are compared with the available measured data. The present study indicates that stall inception is mildly affected by the distortion pattern generated by the inlet with the current test set-up. The numerical study indicates that the inlet distortion pattern decays significantly before it reaches the fan face for the current configuration. Numerical results with a shorter distance between the inlet and fan show that counter-rotating vortices near the rotor tip due to the serpentine diffuser affects fan characteristics significantly.

  2. Flexible ultrasonic pipe inspection apparatus

    DOEpatents

    Jenkins, C.F.; Howard, B.D.

    1994-01-01

    Pipe crawlers, pipe inspection {open_quotes}rabbits{close_quotes} and similar vehicles are widely used for inspecting the interior surfaces of piping systems, storage tanks and process vessels for damaged or flawed structural features. This paper describes the design of a flexible, modular ultrasonic pipe inspection apparatus.

  3. Experimenting with a "Pipe" Whistle

    ERIC Educational Resources Information Center

    Stafford, Olga

    2012-01-01

    A simple pipe whistle can be made using pieces of PVC pipe. The whistle can be used to measure the resonant frequencies of open or closed pipes. A slightly modified version of the device can be used to also investigate the interesting dependence of the sound frequencies produced on the orifice-to-edge distance. The pipe whistle described here…

  4. General Investigation of Tidal Inlets: Stability of Selected United States Tidal Inlets

    DTIC Science & Technology

    1991-09-01

    years, the US Army Corps of Engineers, through its Civil Works program, has sponsored research into the behavior and character- istics of tidal inlets...73 5 50 Siletz, OR 7-39 to 2-76 4 51 Netarts, OR 7-53 to 7-73 4 Report Organizacion 8. Previous research on tidal inlet stability is summarized in Part...I. 1928. "Inlets on Sandy Coasts," Proceedings of the American Society of Civil Engineers, Vol LIV, pp 505-553. Bruun, P. 1967. Tidal Inlets and

  5. An electrohydrodynamic heat pipe.

    NASA Technical Reports Server (NTRS)

    Jones, T. B.

    1972-01-01

    A heat pipe of new design, using an electrode structure to orient and guide the dielectric liquid phase flow, is proposed. Analysis indicates that the operation of the electrohydrodynamic heat pipe is in direct analogy to capillary devices, with the polarization force acting in place of capillarity. Advantages of these new heat pipes include greatly reduced liquid friction, electrohydrodynamically enhanced evaporation and condensation heat transfer, and a possible voltage-controlled on/off feature. Preliminary calculations indicate that relatively high performance devices are possible.

  6. Gas pipe explorer robot

    NASA Technical Reports Server (NTRS)

    Wilcox, Brian (Inventor)

    2004-01-01

    A gas pipe explorer formed of a plurality of connecting elements, and an articulation element between the connected elements. The connected elements include drive capabilities, and the articulation element allows the connected elements to traverse gas pipes of arbitrary shapes and sizes. A sensor may sends the characteristics of the gas pipe, and the communication element may send back those sends characteristics. The communication can be wired, over a tether connecting the device to a remote end. Alternatively, the connection can be wireless, driven by either a generator or a battery.

  7. Electrohydrodynamic heat pipes.

    NASA Technical Reports Server (NTRS)

    Jones, T. B.

    1973-01-01

    An electrohydrodynamic heat pipe of radical design is proposed which substitutes polarization electrohydrodynamic force effects for capillarity in collecting, guiding, and pumping a condensate liquid phase. The discussed device is restricted to the use of dielectric liquids as working fluids. Because of the relatively poor thermal transport properties of these liquids, capillary heat pipes using these liquids have not been high performance devices. The employment of the electrohydrodynamic concept should enhance this performance and help fill the performance gap that exists in the temperature range from 250 F to 750 F for 'conventional' capillary heat pipes.

  8. Regimes of oscillation and reed vibrations in lingual organ pipes

    NASA Astrophysics Data System (ADS)

    Cox, Eric; Rossing, Thomas D.

    2002-05-01

    We compare the sound generation in six lingual organ pipes including two trompette pipes, two oboes pipes, a krummhorn, and a rankett, the latter two of which were described in a previous paper [Cox and Rossing, paper 2aMU8, 142nd ASA meeting]. With the resonator attached, each pipe sounds in distinct regimes of oscillation, separated by discontinuities. The nominal frequencies of the pipes are generally slightly lower than the resonance frequency of the resonator but slightly higher than the natural frequency of the reed. The air mass loading of both the resonator and shallot lowers the reed frequency. Changing the blowing pressure has little effect on the sounding frequency but a modest effect on sound level.

  9. Improved Thin, Flexible Heat Pipes

    NASA Technical Reports Server (NTRS)

    Rosenfeld, John H.; Gernert, Nelson J.; Sarraf, David B.; Wollen, Peter J.; Surina, Frank C.; Fale, John E.

    2004-01-01

    Flexible heat pipes of an improved type are fabricated as layers of different materials laminated together into vacuum- tight sheets or tapes. In comparison with prior flexible heat pipes, these flexible heat pipes are less susceptible to leakage. Other advantages of these flexible heat pipes, relative to prior flexible heat pipes, include high reliability and greater ease and lower cost of fabrication. Because these heat pipes are very thin, they are highly flexible. When coated on outside surfaces with adhesives, these flexible heat pipes can be applied, like common adhesive tapes, to the surfaces of heat sinks and objects to be cooled, even if those surfaces are curved.

  10. MTR, TRA603. SUBBASEMENT FLOOR PLAN. INLET/OUTLET TUNNELS FOR COOLANT WATER ...

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

    MTR, TRA-603. SUB-BASEMENT FLOOR PLAN. INLET/OUTLET TUNNELS FOR COOLANT WATER (NORTH SIDE) AND AIR (SOUTH SIDE). RABBIT CANAL AND BULKHEADS. SUMPS AND DRAINS. BLAW-KNOX 3150-3-7, 3/1950. INL INDEX NO. 531-0603-00-098-100006, REV. 4. - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

  11. The stability of pipe entrance flows subjected to axisymmetric disturbances

    SciTech Connect

    Silva, D.F. da; Moss, E.A. . School of Mechanical Engineering)

    1994-03-01

    This paper reexamines an important unresolved problem in fluid mechanics--the discrepancy between measurements and predictions of stability in pipe entrance flows. Whereas measured critical Reynolds numbers are relatively insensitive to velocity profile shape in the streamwise direction, the theoretical results indicate a rapid increase, both as the equilibrium profile is approached, and toward the inlet. The current work uses the displacement thickness based Reynolds number as a rational basis on which to compare new stability predictions obtained by means of the Q-Z algorithm, with existing theoretical results. Although the present data are shown to be the only data that are consistent with the classical parallel boundary layer limit towards the inlet, they still deviate increasingly with axial distance from the only available experimental results. By examining pipe inlet stability data in relation to boundary layer measurements and predictions, the work effectively questions the commonly held belief that streamwise variations of flow alone are responsible for these deviations, suggesting that the finite amplitude nature of the applied disturbances is the most likely cause.

  12. Liquefied Bleed for Stability and Efficiency of High Speed Inlets

    NASA Technical Reports Server (NTRS)

    Saunders, J. David; Davis, David; Barsi, Stephen J.; Deans, Matthew C.; Weir, Lois J.; Sanders, Bobby W.

    2014-01-01

    A mission analysis code was developed to perform a trade study on the effectiveness of liquefying bleed for the inlet of the first stage of a TSTO vehicle. By liquefying bleed, the vehicle weight (TOGW) could be reduced by 7 to 23%. Numerous simplifying assumptions were made and lessons were learned. Increased accuracy in future analyses can be achieved by: Including a higher fidelity model to capture the effect of rescaling (variable vehicle TOGW). Refining specific thrust and impulse models ( T m a and Isp) to preserve fuel-to-air ratio. Implementing LH2 for T m a and Isp. Correlating baseline design to other mission analyses and correcting vehicle design elements. Implementing angle-of-attack effects on inlet characteristics. Refining aerodynamic performance (to improve L/D ratio at higher Mach numbers). Examining the benefit with partial cooling or densification of the bleed air stream. Incorporating higher fidelity weight estimates for the liquefied bleed system (heat exchange and liquid storage versus bleed duct weights) could be added when more fully developed. Adding trim drag or 6-degree-of-freedom trajectory analysis for higher fidelity. Investigating vehicle optimization for each of the bleed configurations.

  13. Miniature pipe crawler tractor

    DOEpatents

    McKay, Mark D.; Anderson, Matthew O.; Ferrante, Todd A.; Willis, W. David

    2000-01-01

    A pipe crawler tractor may comprise a half tractor assembly having a first base drive wheel, a second base drive wheel, and a top drive wheel. The drive wheels are mounted in spaced-apart relation so that the top drive wheel is positioned between the first and second base drive wheels. The mounting arrangement is also such that the first and second base drive wheels contact the inside surface of the pipe at respective first and second positions and so that the top drive wheel contacts the inside surface of the pipe at a third position, the third position being substantially diametrically opposed to the first and second positions. A control system connected to the half tractor assembly controls the rotation of the first base wheel, the second base wheel, and the top drive wheel to move the half tractor assembly within the pipe.

  14. An electrohydrodynamic heat pipe

    NASA Technical Reports Server (NTRS)

    Jones, T. B.

    1972-01-01

    Dielectric liquid for transfer of heat provides liquid flow from the condenser section to the evaporator section in conventional heat pipes. Working fluid is guided or pumped by an array of wire electrodes connected to a high-voltage source.

  15. The pipes of pan.

    PubMed

    Chalif, David J

    2004-12-01

    The pipes of pan is the crowning achievement of Pablo Picasso's neoclassical period of the 1920s. This monumental canvas depicts a mythological Mediterranean scene in which two sculpted classical giants stare out, seemingly across the centuries, toward a distant and lost Arcadia. Picasso was influenced by Greco-Roman art during his travels in Italy, and his neoclassical works typically portray massive, immobile, and pensive figures. Pan and his pipes are taken directly from Greek mythological lore by Picasso and placed directly into 20th century art. He frequently turned to various mythological figures throughout his metamorphosing periods. The Pipes of Pan was also influenced by the painter's infatuation with the beautiful American expatriate Sara Murphy, and the finished masterpiece represents a revision of a previously conceived neoclassical work. The Pipes of Pan now hangs in the Musee Picasso in Paris.

  16. Heat pipe manufacturing study

    NASA Technical Reports Server (NTRS)

    Edelstein, F.

    1974-01-01

    Heat pipe manufacturing methods are examined with the goal of establishing cost effective procedures that will ultimately result in cheaper more reliable heat pipes. Those methods which are commonly used by all heat pipe manufacturers have been considered, including: (1) envelope and wick cleaning, (2) end closure and welding, (3) mechanical verification, (4) evacuation and charging, (5) working fluid purity, and (6) charge tube pinch off. The study is limited to moderate temperature aluminum and stainless steel heat pipes with ammonia, Freon-21 and methanol working fluids. Review and evaluation of available manufacturers techniques and procedures together with the results of specific manufacturing oriented tests have yielded a set of recommended cost-effective specifications which can be used by all manufacturers.

  17. Heat pipe development

    NASA Technical Reports Server (NTRS)

    Bienart, W. B.

    1973-01-01

    The objective of this program was to investigate analytically and experimentally the performance of heat pipes with composite wicks--specifically, those having pedestal arteries and screwthread circumferential grooves. An analytical model was developed to describe the effects of screwthreads and screen secondary wicks on the transport capability of the artery. The model describes the hydrodynamics of the circumferential flow in triangular grooves with azimuthally varying capillary menisci and liquid cross-sections. Normalized results were obtained which give the influence of evaporator heat flux on the axial heat transport capability of the arterial wick. In order to evaluate the priming behavior of composite wicks under actual load conditions, an 'inverted' glass heat pipe was designed and constructed. The results obtained from the analysis and from the tests with the glass heat pipe were applied to the OAO-C Level 5 heat pipe, and an improved correlation between predicted and measured evaporator and transport performance were obtained.

  18. Heat Pipe Systems

    NASA Technical Reports Server (NTRS)

    1993-01-01

    The heat pipe was developed to alternately cool and heat without using energy or any moving parts. It enables non-rotating spacecraft to maintain a constant temperature when the surface exposed to the Sun is excessively hot and the non Sun-facing side is very cold. Several organizations, such as Tropic-Kool Engineering Corporation, joined NASA in a subsequent program to refine and commercialize the technology. Heat pipes have been installed in fast food restaurants in areas where humid conditions cause materials to deteriorate quickly. Moisture removal was increased by 30 percent in a Clearwater, FL Burger King after heat pipes were installed. Relative humidity and power consumption were also reduced significantly. Similar results were recorded by Taco Bell, which now specifies heat pipe systems in new restaurants in the Southeast.

  19. Liquid Explosive in Pipes

    DTIC Science & Technology

    1994-01-01

    ETH - ethanolamine, ED - ethylenediamine, HMT - hexamethylenetetramine , MOR - morpholine. NM - nitromethane, PYR - pyridine, TETA...ror a detonable mixture in 16-mm ID pipe: diethylamine, diethylenetetramine, ethanolamine, ethylenediamine, hexamethylenetetramine , morpholine

  20. Turbofan blade stresses induced by the flow distortion of a VTOL inlet at high angles of attack

    NASA Technical Reports Server (NTRS)

    Williams, R. C.; Diedrich, J. H.; Shaw, R. J.

    1983-01-01

    A 51-cm-diameter turbofan with a tilt-nacelle VTOL inlet was tested in the Lewis Research Center's 9- by 15-Ft Low Speed Wind Tunnel at velocities up to 72 m/s and angles of attack up to 120 deg. Fan-blade vibratory stress levels were investigated over a full aircraft operating range. These stresses were due to inlet air flow distortion resulting from (1) internal flow separation in the inlet, and (2) ingestion of the exterior nacelle wake. Stress levels are presented, along with an estimated safe operating envelope, based on infinite blade fatigue life.

  1. Turbine Inlet Analysis of Injected Water Droplet Behavior

    NASA Astrophysics Data System (ADS)

    Hargrave, Kevin

    Gas turbines have become widely used in the generation of power for cities. They are used all over the world and must operate under a wide variety of ambient conditions. Every turbine has a temperature at which it operates at peak capacity. In order to attain this temperature in the hotter months various cooling methods are used such as refrigeration inlet cooling systems, evaporative methods, and thermal energy storage systems. One of the more widely used is the evaporative systems because it is one of the safest and easiest to utilize method. However, the behavior of water droplets within the inlet to the turbine has not been extensively studied or documented. It is important to understand how the droplets behave within the inlet so that water droplets above a critical diameter will not enter the compressor and cause damage to the compressor blades. In order to do this a FLUENT simulation was constructed in order to determine the behavior of the water droplets and if any droplets remain at the exit of the inlet, along with their size. In order to do this several engineering drawings were obtained from SRP and studies in order to obtain the correct dimensions. Then the simulation was set up using data obtained from SRP and Parker-Hannifin, the maker of the spray nozzles. Then several sets of simulations were run in order to see how the water droplets behaved under various conditions. These results were then analyzed and quantified so that they could be easily understood. The results showed that the possible damage to the compressor increased with increasing temperature at a constant relative humidity. This is due in part to the fact that in order to keep a constant relative humidity at varying temperatures the mass fraction of water vapor in the air must be changed. As temperature increases the water vapor mass fraction must increase in order to maintain a constant relative humidity. This in turn makes it slightly increases the evaporation time of the water

  2. Silicon Heat Pipe Array

    NASA Technical Reports Server (NTRS)

    Yee, Karl Y.; Ganapathi, Gani B.; Sunada, Eric T.; Bae, Youngsam; Miller, Jennifer R.; Beinsford, Daniel F.

    2013-01-01

    Improved methods of heat dissipation are required for modern, high-power density electronic systems. As increased functionality is progressively compacted into decreasing volumes, this need will be exacerbated. High-performance chip power is predicted to increase monotonically and rapidly with time. Systems utilizing these chips are currently reliant upon decades of old cooling technology. Heat pipes offer a solution to this problem. Heat pipes are passive, self-contained, two-phase heat dissipation devices. Heat conducted into the device through a wick structure converts the working fluid into a vapor, which then releases the heat via condensation after being transported away from the heat source. Heat pipes have high thermal conductivities, are inexpensive, and have been utilized in previous space missions. However, the cylindrical geometry of commercial heat pipes is a poor fit to the planar geometries of microelectronic assemblies, the copper that commercial heat pipes are typically constructed of is a poor CTE (coefficient of thermal expansion) match to the semiconductor die utilized in these assemblies, and the functionality and reliability of heat pipes in general is strongly dependent on the orientation of the assembly with respect to the gravity vector. What is needed is a planar, semiconductor-based heat pipe array that can be used for cooling of generic MCM (multichip module) assemblies that can also function in all orientations. Such a structure would not only have applications in the cooling of space electronics, but would have commercial applications as well (e.g. cooling of microprocessors and high-power laser diodes). This technology is an improvement over existing heat pipe designs due to the finer porosity of the wick, which enhances capillary pumping pressure, resulting in greater effective thermal conductivity and performance in any orientation with respect to the gravity vector. In addition, it is constructed of silicon, and thus is better

  3. Freezable heat pipe

    DOEpatents

    Ernst, Donald M.; Sanzi, James L.

    1981-02-03

    A heat pipe whose fluid can be repeatedly frozen and thawed without damage to the casing. An additional part is added to a conventional heat pipe. This addition is a simple porous structure, such as a cylinder, self-supporting and free standing, which is dimensioned with its diameter not spanning the inside transverse dimension of the casing, and with its length surpassing the depth of maximum liquid.

  4. Investigation of Flow Instabilities in the Inlet Ducts of DP-1C VTOL Aircraft

    NASA Technical Reports Server (NTRS)

    Lepicovsky, Jan

    2008-01-01

    An investigation of flow instabilities in the inlet ducts of a two-engine vertical takeoff and landing aircraft DP-1C is described in this report. Recent tests revealed that the engines stall during run ups while the aircraft is operating on the ground. These pop stalls occurred at relatively low power levels, sometimes as low as 60 percent of the engine full speed. Inability to run the engines up to the full speed level is attributed to in-ground effects associated with hot gas ingestion. Such pop stalls were never experienced when the aircraft was tested on a elevated grid platform, which ensured that the aircraft was operating in out-of-the-ground-effect conditions. Based on available information on problems experienced with other vertical takeoff and landing aircraft designs, it was assumed that the engine stalls were caused by partial ingestion of hot gases streaming forward from the main exit nozzle under the aircraft inlets, which are very close to the ground. It was also suggested that the nose wheel undercarriage, located between the inlets, may generate vortices or an unstable wake causing intense mixing of hot exit gases with incoming inlet flow, which would enhance the hot gas ingestion. After running a short three-day series of tests with fully instrumented engine inlets, it is now believed the most probable reason for engine pop stalls are random ingestions of a vortex generated between the two streams moving in opposite directions: outbound hot gas stream from the main nozzle close to the ground and inbound inlet flow above. Originally, the vortex is in a horizontal plane. However, at a certain velocity ratio of these two streams, the vortex attaches either to the ground or the aircraft surface at one end and the other end is swallowed by one of the aircraft inlets. Once the vortex enters the inlet duct, a puff of hot air can be sucked through the vortex core into the engine, which causes a serious inlet flow field distortion followed by an engine

  5. 33 CFR 80.703 - Little River Inlet, SC to Cape Romain, SC.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Inlet, a line drawn parallel with the general trend of the highwater shoreline across Hog Inlet; thence... the general trend of the highwater shoreline across Midway Inlet, Pawleys Inlet, and North Inlet....

  6. Heat pipe dynamic behavior

    NASA Technical Reports Server (NTRS)

    Issacci, F.; Roche, G. L.; Klein, D. B.; Catton, I.

    1988-01-01

    The vapor flow in a heat pipe was mathematically modeled and the equations governing the transient behavior of the core were solved numerically. The modeled vapor flow is transient, axisymmetric (or two-dimensional) compressible viscous flow in a closed chamber. The two methods of solution are described. The more promising method failed (a mixed Galerkin finite difference method) whereas a more common finite difference method was successful. Preliminary results are presented showing that multi-dimensional flows need to be treated. A model of the liquid phase of a high temperature heat pipe was developed. The model is intended to be coupled to a vapor phase model for the complete solution of the heat pipe problem. The mathematical equations are formulated consistent with physical processes while allowing a computationally efficient solution. The model simulates time dependent characteristics of concern to the liquid phase including input phase change, output heat fluxes, liquid temperatures, container temperatures, liquid velocities, and liquid pressure. Preliminary results were obtained for two heat pipe startup cases. The heat pipe studied used lithium as the working fluid and an annular wick configuration. Recommendations for implementation based on the results obtained are presented. Experimental studies were initiated using a rectangular heat pipe. Both twin beam laser holography and laser Doppler anemometry were investigated. Preliminary experiments were completed and results are reported.

  7. A Corrosion Risk Assessment Model for Underground Piping

    NASA Technical Reports Server (NTRS)

    Datta, Koushik; Fraser, Douglas R.

    2009-01-01

    The Pressure Systems Manager at NASA Ames Research Center (ARC) has embarked on a project to collect data and develop risk assessment models to support risk-informed decision making regarding future inspections of underground pipes at ARC. This paper shows progress in one area of this project - a corrosion risk assessment model for the underground high-pressure air distribution piping system at ARC. It consists of a Corrosion Model of pipe-segments, a Pipe Wrap Protection Model; and a Pipe Stress Model for a pipe segment. A Monte Carlo simulation of the combined models provides a distribution of the failure probabilities. Sensitivity study results show that the model uncertainty, or lack of knowledge, is the dominant contributor to the calculated unreliability of the underground piping system. As a result, the Pressure Systems Manager may consider investing resources specifically focused on reducing these uncertainties. Future work includes completing the data collection effort for the existing ground based pressure systems and applying the risk models to risk-based inspection strategies of the underground pipes at ARC.

  8. Inlet contour and flow effects on radiation

    NASA Technical Reports Server (NTRS)

    Ville, J. M.; Silcox, R. J.

    1980-01-01

    An experimental investigation of sound radiation from inlets with different contours with and without flow is being conducted to study the possibility of reducing noise radiated by aircraft engines. For each inlet configuration, complex directivity patterns and complex pressure reflection coefficients are measured as a function of a single space-time structure of the wave (up to a frequency of 4000Hz and an azimuthal wave number 6) and of flow velocity (up to Mach number 0.4) in a cylindrical duct located downstream the inlet. Experimental results of radiation from an unflanged duct are compared with theory. Effect of inlet contour and flow are deduced by comparing respectively unflanged duct and bellmouth measurements and, no flow and flow measurements with the bellmouth. Results are presented which indicate that the contour effect is significant near the cut-on frequency of a mode and emphasize the necessity for taking into account the inlet geometry in a radiation prediction. These results show also that internal flow has a weak effect on the amplitude of the directivity pattern

  9. Analysis of Buzz in a Supersonic Inlet

    NASA Technical Reports Server (NTRS)

    Chima, Rodrick V.

    2012-01-01

    A dual-stream, low-boom supersonic inlet designed for use on a small, Mach 1.6 aircraft was tested experimentally in the 8- by 6-Foot Supersonic Wind Tunnel (SWT) at the NASA Glenn Research Center (GRC). The tests showed that the inlet had good recovery and stable operation over large mass flow range. The inlet went into buzz at mass flows well below that needed for engine operation, and the experiments generated a wealth of data during buzz. High frequency response pressure measurements and high-speed schlieren videos were recorded for many buzz events. The objective of the present work was to use computational fluid dynamics (CFD) to predict some of the experimental data taken during buzz, compare those predictions to the experimental data, and to use both datasets to explain the physics of the buzz cycle. The calculations were done with the Wind-US CFD code using a second-order time-accurate differencing scheme and the SST turbulence model. Computed Mach number contours were compared with schlieren images, and ensemble-averaged unsteady pressures were compared to data. The results showed that the buzz cycle consisted partly of spike buzz, an unsteady oscillation of the main shock at the spike tip while the inlet pressure dropped, and partly of choked flow while the inlet repressurized. Most of the results could be explained by theory proposed by Dailey in 1954, but did not support commonly used acoustic resonance explanations.

  10. Solid sorbent air sampler

    NASA Astrophysics Data System (ADS)

    Galen, T. J.

    1986-04-01

    A fluid sampler for collecting a plurality of discrete samples over separate time intervals is described. The sampler comprises a sample assembly having an inlet and a plurality of discreet sample tubes each of which has inlet and outlet sides. A multiport dual acting valve is provided in the sampler in order to sequentially pass air from the sample inlet into the selected sample tubes. The sample tubes extend longitudinally of the housing and are located about the outer periphery thereof so that upon removal of an enclosure cover, they are readily accessible for operation of the sampler in an analysis mode.

  11. Solid sorbent air sampler

    NASA Technical Reports Server (NTRS)

    Galen, T. J. (Inventor)

    1986-01-01

    A fluid sampler for collecting a plurality of discrete samples over separate time intervals is described. The sampler comprises a sample assembly having an inlet and a plurality of discreet sample tubes each of which has inlet and outlet sides. A multiport dual acting valve is provided in the sampler in order to sequentially pass air from the sample inlet into the selected sample tubes. The sample tubes extend longitudinally of the housing and are located about the outer periphery thereof so that upon removal of an enclosure cover, they are readily accessible for operation of the sampler in an analysis mode.

  12. Distribution and sources of polychlorinated biphenyls in Woods Inlet, Lake Worth, Fort Worth, Texas, 2003

    USGS Publications Warehouse

    Besse, Richard E.; Van Metre, Peter C.; Wilson, Jennifer T.

    2005-01-01

    Woods Inlet is a flooded stream channel on the southern shore of Lake Worth along the western boundary of Air Force Plant 4 in Fort Worth, Texas, where elevated polychlorinated biphenyl (PCB) concentrations in sediment were detected in a previous study. In response, the U.S. Geological Survey, in cooperation with the U.S. Air Force, conducted a study in 2003 to map the extent of elevated PCB concentrations in Woods Inlet and to identify possible sources (or more specifically, source areas) of PCBs in the watershed of Woods Inlet. Three gravity cores (penetration to pre-reservoir sediment at three sites) and 17 box cores (surficial bottom sediment samples) were collected in Woods Inlet. Suspended sediment in stormwater runoff and streambed sediment were sampled in tributaries to Woods Inlet following storms. Assemblages of PCB congeners in surficial inlet sediments and suspended and streambed sediments were analyzed to indicate sources of PCBs in the inlet sediments on the basis of chemical signatures of PCBs. Woods Inlet receives runoff primarily from three tributaries: (1) Gruggs Park Creek, (2) the small unnamed creek that drains a Texas National Guard maintenance facility, called TNG Creek for this report, and (3) Meandering Road Creek. Twenty-seven of 209 possible PCB congeners were analyzed. The sum of the congeners was used as a measure of total PCB. The spatial distribution of total PCB concentrations in the inlet indicates that most PCBs are originating in the Meandering Road Creek watershed. Peak total PCB concentrations in the three gravity cores occurred at depths corresponding to sediment deposition dates of about 1960 for two of the cores and about 1980 for the third core. The magnitudes of peak total PCB concentrations in the gravity cores followed a spatial distribution generally similar to that of surficial bottom sediment concentrations. Total PCB concentrations in suspended and streambed sediment varied greatly between sites and indicated a likely

  13. Numerical investigation of temperature distribution in an eroded bend pipe and prediction of erosion reduced thickness.

    PubMed

    Zhu, Hongjun; Feng, Guang; Wang, Qijun

    2014-01-01

    Accurate prediction of erosion thickness is essential for pipe engineering. The objective of the present paper is to study the temperature distribution in an eroded bend pipe and find a new method to predict the erosion reduced thickness. Computational fluid dynamic (CFD) simulations with FLUENT software are carried out to investigate the temperature field. And effects of oil inlet rate, oil inlet temperature, and erosion reduced thickness are examined. The presence of erosion pit brings about the obvious fluctuation of temperature drop along the extrados of bend. And the minimum temperature drop presents at the most severe erosion point. Small inlet temperature or large inlet velocity can lead to small temperature drop, while shallow erosion pit causes great temperature drop. The dimensionless minimum temperature drop is analyzed and the fitting formula is obtained. Using the formula we can calculate the erosion reduced thickness, which is only needed to monitor the outer surface temperature of bend pipe. This new method can provide useful guidance for pipeline monitoring and replacement.

  14. Experimental Investigation of a Hypersonic Inlet with Variable Sidewall for Flow Control

    NASA Astrophysics Data System (ADS)

    Rolim, T. C.; Lu, F. K.

    The main function of a scramjet inlet is to decelerate and compress the air for subsequent reaction with the fuel inside the combustor and, of course, contribute toward meeting the thrust requirement for the entire mission by providing adequate mass flow. It is desirable that the inlet be lightweight and that its geometry be capable of producing a uniform flow in an appropriate state to permit efficient mixing and subsequent combustion. Engine cycle analysis indicates that high contraction ratios CR are desirable for achieving high overall engine efficiency.

  15. Flexible pipe crawling device having articulated two axis coupling

    DOEpatents

    Zollinger, William T.

    1994-01-01

    An apparatus for moving through the linear and non-linear segments of piping systems. The apparatus comprises a front leg assembly, a rear leg assembly, a mechanism for extension and retraction of the front and rear leg assembles with respect to each other, such as an air cylinder, and a pivoting joint. One end of the flexible joint attaches to the front leg assembly and the other end to the air cylinder, which is also connected to the rear leg assembly. The air cylinder allows the front and rear leg assemblies to progress through a pipe in "inchworm" fashion, while the joint provides the flexibility necessary for the pipe crawler to negotiate non-linear piping segments. The flexible connecting joint is coupled with a spring-force suspension system that urges alignment of the front and rear leg assemblies with respect to each other. The joint and suspension system cooperate to provide a firm yet flexible connection between the front and rear leg assemblies to allow the pivoting of one with respect to the other while moving around a non-linear pipe segment, but restoring proper alignment coming out of the pipe bend.

  16. Flexible pipe crawling device having articulated two axis coupling

    DOEpatents

    Zollinger, W.T.

    1994-05-10

    An apparatus is described for moving through the linear and non-linear segments of piping systems. The apparatus comprises a front leg assembly, a rear leg assembly, a mechanism for extension and retraction of the front and rear leg assembles with respect to each other, such as an air cylinder, and a pivoting joint. One end of the flexible joint attaches to the front leg assembly and the other end to the air cylinder, which is also connected to the rear leg assembly. The air cylinder allows the front and rear leg assemblies to progress through a pipe in inchworm' fashion, while the joint provides the flexibility necessary for the pipe crawler to negotiate non-linear piping segments. The flexible connecting joint is coupled with a spring-force suspension system that urges alignment of the front and rear leg assemblies with respect to each other. The joint and suspension system cooperate to provide a firm yet flexible connection between the front and rear leg assemblies to allow the pivoting of one with respect to the other while moving around a non-linear pipe segment, but restoring proper alignment coming out of the pipe bend. 4 figures.

  17. Dynamics of swirling flows Induced by twisted tapes in circular pipes

    NASA Astrophysics Data System (ADS)

    Cazan, Radu

    The present study describes the flow characteristics of swirling flows induced by twisted tape inserts in circular pipes. The study is focused on the secondary flow which is investigated experimentally and with numerical models. The results are expected to improve the paper manufacturing process by identifying and removing the detrimental secondary flow. Experimental tests show for the first time the existence of two co-rotating helical vortices superimposed over the main swirling flow, downstream of twisted tapes. The close proximity of the two co-rotating vortices creates a local counter-rotating flow at the pipe centerline. The flow is analyzed using LDV measurements and high speed camera visualization with fine air bubbles seeding which confirm that the helical vortices are stable. After extracting the characteristic tangential velocity profiles of the main vortex and of the two secondary vortices, it was observed that the maximum tangential velocity of all three vortices is the same, approximately half of the bulk velocity. The winding of the helical vortices is in the swirl direction and the pitch of the helical vortices is found to be independent of the inlet velocity. The experimental findings are confirmed by numerical simulations. The numerical results show that the helical vortices originate inside the swirler and evolve from single co-rotating vortices on each side of the tape. The flow characteristics are analyzed in detail. Swirlers with multiple twists and multiple chambers are shown to have less stable secondary motion and could be employed in applications were the secondary motion is detrimental.

  18. Numerical simulation of scramjet inlet flow fields

    NASA Technical Reports Server (NTRS)

    Kumar, Ajay

    1986-01-01

    A computer program was developed to analyze supersonic combustion ramjet (scramjet) inlet flow fields. The program solves the three-dimensional Euler or Reynolds averaged Navier-Stokes equations in full conservation form by either the fully explicit or explicit-implicit, predictor-corrector method of MacCormack. Turbulence is modeled by an algebraic eddy-viscosity model. The analysis allows inclusion of end effects which can significantly affect the inlet flow field. Detailed laminar and turbulent flow results are presented for a symmetric-wedge corner, and comparisons are made with the available experimental results to allow assessment of the program. Results are then presented for two inlet configurations for which experimental results exist at the NASA Langley Research Center.

  19. Miniature piezo electric vacuum inlet valve

    DOEpatents

    Keville, R.F.; Dietrich, D.D.

    1998-03-24

    A miniature piezo electric vacuum inlet valve having a fast pulse rate and is battery operated with variable flow capability is disclosed. The low power (<1.6 watts), high pulse rate (<2 milliseconds), variable flow inlet valve is utilized for mass spectroscopic applications or other applications where pulsed or continuous flow conditions are needed. The inlet valve also has a very minimal dead volume of less than 0.01 std/cc. The valve can utilize, for example, a 12 Vdc input/750 Vdc, 3 mA output power supply compared to conventional piezo electric valves which require preloading of the crystal drive mechanism and 120 Vac, thus the valve of the present invention is smaller by a factor of three. 6 figs.

  20. Miniature piezo electric vacuum inlet valve

    DOEpatents

    Keville, Robert F.; Dietrich, Daniel D.

    1998-03-24

    A miniature piezo electric vacuum inlet valve having a fast pulse rate and is battery operated with variable flow capability. The low power (<1.6 watts), high pulse rate (<2 milliseconds), variable flow inlet valve is utilized for mass spectroscopic applications or other applications where pulsed or continuous flow conditions are needed. The inlet valve also has a very minimal dead volume of less than 0.01 std/cc. The valve can utilize, for example, a 12 Vdc input/750 Vdc, 3 mA output power supply compared to conventional piezo electric valves which require preloading of the crystal drive mechanism and 120 Vac, thus the valve of the present invention is smaller by a factor of three.

  1. Analysis of thrust augmentation of turbojet engines by water injection at compressor inlet including charts for calculating compression processes with water injection

    NASA Technical Reports Server (NTRS)

    Wilcox, E Clinton; Trout, Arthur M

    1951-01-01

    A psychrometric chart having total pressure (sum of partial pressures of air and water vapor) as a variable, a Mollier diagram for air saturated with water vapor, and charts showing the thermodynamic properties of various air-water vapor and exhaust gas-water vapor mixtures are presented as aids in calculating the thrust augmentation of a turbojet engine resulting from the injection of water at the compressor inlet. Curves are presented that show the theoretical performance of the augmentation method for various amounts of water injected and the effects of varying flight Mach number, altitude, ambient-air temperature, ambient relative humidity, compressor pressure ratio, and inlet-diffuser efficiency. Numerical examples, illustrating the use of the psychrometric chart and the Mollier diagram in calculating both compressor-inlet and compressor-outlet conditions when water is injected at the compressor inlet, are presented.

  2. Osborne Reynolds' pipe flow: Direct computation from laminar through bypass transition to fully-developed turbulence

    NASA Astrophysics Data System (ADS)

    Wu, Xiaohua; Moin, Parviz; Adrian, Ronald; Baltzer, Jon; Hickey, Jean-Pierre

    2012-11-01

    The most fundamental internal flow, smooth pipe from a slightly perturbed laminar inlet state continuously through bypass transition to fully-developed turbulence, has been computed using DNS over an axial domain length of 250 pipe radii. In the fully-developed turbulent region, mean and second-order turbulent statistics including the rate of viscous dissipation show excellent agreement with those obtained from an additional simulation using the conventional streamwise periodic boundary condition over an axial domain length of 30 pipe radii. Friction factor follows analytical solution prior to breakdown, and agrees with Moody's correlation after the completion of transition. During transition it exhibits an overshoot. Breakdown of the laminar pipe flow is characterized by the formation of large Lambda-shaped vortices pointing upstream, followed by their subsequent generation of small hairpin packets inclined towards the downstream direction.

  3. Wedgethread pipe connection

    DOEpatents

    Watts, John D.

    2003-06-17

    Several embodiments of a wedgethread pipe connection are disclosed that have improved makeup, sealing, and non-loosening characteristics. In one embodiment, an open wedgethread is disclosed that has an included angle measured in the gap between the stab flank and the load flank to be not less than zero, so as to prevent premature wedging between mating flanks before the position of full makeup is reached, as does occur between trapped wedgethreads wherein the included angle is less than zero. The invention may be used for pipe threads large or small, as a flush joint, with collars, screwed into plates or it may even be used to reversibly connect such as solid posts to base members where a wide makeup torque range is desired. This Open wedgethread, as opposed to trapped wedgethreads, provides a threaded pipe connection that: is more cost-effective; can seal high pressure gas; can provide selectively a connection strength as high as the pipe strength; assures easy makeup to the desired position of full makeup within a wide torque range; may have a torque strength as high as the pipe torque strength; is easier to manufacture; is easier to gage; and is less subject to handling damage.

  4. Investigation of Unsteady Flow Interaction Between an Ultra-Compact Inlet and a Transonic Fan

    NASA Technical Reports Server (NTRS)

    Hah, Chunill; Rabe, Douglas; Scribben, Angie

    2015-01-01

    In the study presented, unsteady flow interaction between an ultra-compact inlet and a transonic fan stage is investigated. Future combat aircraft engines require ultra-compact inlet ducts as part of an integrated, advanced propulsion system to improve air vehicle capability and effectiveness to meet future mission needs. The main purpose of the current study is to advance the understanding of the flow interaction between a modern ultra-compact inlet and a transonic fan for future design applications. Many experimental/ analytical studies have been reported on the aerodynamics of compact inlets in aircraft engines. On the other hand, very few studies have been reported on the effects of flow distortion from these inlets on the performance of the following fan/compressor stages. The primary goal of the study presented is to investigate how flow interaction between an ultra-compact inlet and a transonic compressor influence the operating margin of the compressor. Both Unsteady Reynolds-averaged Navier-Stokes (URANS) and Large Eddy Simulation (LES) approaches are used to calculate the unsteady flow field, and the numerical results are used to study the flow interaction. The present study indicates that stall inception of the following compressor stage is affected directly based on how the distortion pattern evolves before it interacts with the fan/compressor face. For the present compressor, the stall initiates at the tip section with clean inlet flow and distortion pattern away from the casing itself seems to have limited impacts on the stall inception of the compressor. A counter-rotating swirl, which is generated due to flow separation inside the s-shaped compact duct, generates an increased flow angle near the blade tip. This increased flow angle near the rotor tip due to the secondary flow from the counter-rotating vortices is the primary reason for the reduced compressor stall margin.

  5. Inlet Housing for a Partial-Admission Turbine

    NASA Technical Reports Server (NTRS)

    Moye, Ralph; Myers, William; Baker, Kevin

    2004-01-01

    An inlet housing for a partial-admission turbine has been designed to cause the inlet airflow to make a smooth transition from an open circular inlet to an inlet slot. The smooth flow is required for purposes of measuring inlet flow characteristics and maximizing the efficiency of the turbine. A partial-admission turbine is a turbine in which the inlet slot occupies less than a complete circle around the rotor axis. In this case, the inlet slot occupies a 90 arc. The present special inlet-housing design is needed because the "bull nose" shape of a conventional turbine inlet housing fails to provide the required smooth transition in a partial-admission configuration and thereby gives rise to a loss of turbine efficiency and inaccuracies in inlet flow measurements. Upon entering the inlet housing through the circular opening, the flow encounters a "tongue"-shaped passageway, which serves as a ramp that diverts the flow to the first of two straight passages. This first passageway occupies a 90 arc and has a length equal to two passage heights. Instrumentation rakes for measuring the characteristics of the inlet flow are installed in this passageway. Just past the first straight passageway is the second one, which is narrower and leads to the 90 turbine inlet slot. This passageway is used to smooth the flow immediately prior to its passage through the turbine inlet slot. The length of this second passageway equals the length of the chord of a turbine vane. The inlet housing incorporates small ports for measuring static pressures at various locations of the flow, and incorporates bosses for the installation of the instrumentation rakes. The inlet housing also includes a flange at its inlet end for attachment to a circular inlet duct and a flange at its outlet end for attachment to the outer casing of the turbine.

  6. An Overview of Long Duration Sodium Heat Pipe Tests

    NASA Technical Reports Server (NTRS)

    Rosenfeld, John H.; Ernst, Donald M.; Lindemuth, James E.; Sanzi, James L.; Geng, Steven M.; Zuo, Jon

    2004-01-01

    High temperature heat pipes are being evaluated for use in energy conversion applications such as fuel cells, gas turbine re-combustors, and Stirling cycle heat sources; with the resurgence of space nuclear power, additional applications include reactor heat removal elements and radiator elements. Long operating life and reliable performance are critical requirements for these applications. Accordingly long-term materials compatibility is being evaluated through the use of high temperature life test heat pipes. Thermacore International, Inc., has carried out several sodium heat pipe life tests to establish long term operating reliability. Four sodium heat pipes have recently demonstrated favorable materials compatibility and heat transport characteristics at high operating temperatures in air over long time periods. A 3l6L stainless steel heat pipe with a sintered porous nickel wick structure and an integral brazed cartridge heater has successfully operated at 650 to 700 C for over 115,000 hours without signs of failure. A second 3l6L stainless steel heat pipe with a specially-designed Inconel 60 I rupture disk and a sintered nickel powder wick has demonstrated over 83,000 hours at 600 to 650 C with similar success. A representative one-tenth segment Stirling Space Power Converter heat pipe with an Inconel 718 envelope and a stainless steel screen wick has operated for over 41 ,000 hours at nearly 700 0c. A hybrid (i.e. gas-fired and solar) heat pipe with a Haynes 230 envelope and a sintered porous nickel wick structure was operated for about 20,000 hours at nearly 700 C without signs of degradation. These life test results collectively have demonstrated the potential for high temperature heat pipes to serve as reliable energy conversion system components for power applications that require long operating lifetime with high reliability, Detailed design specifications, operating hi story, and test results are described for each of these sodium heat pipes. Lessons

  7. An Overview of Long Duration Sodium Heat Pipe Tests

    NASA Astrophysics Data System (ADS)

    Rosenfeld, John H.; Ernst, Donald M.; Lindemuth, James E.; Sanzi, James L.; Geng, Steven M.; Zuo, Jon

    2004-02-01

    High temperature heat pipes are being evaluated for use in energy conversion applications such as fuel cells, gas turbine re-combustors, and Stirling cycle heat sources; with the resurgence of space nuclear power, additional applications include reactor heat removal elements and radiator elements. Long operating life and reliable performance are critical requirements for these applications. Accordingly long-term materials compatibility is being evaluated through the use of high temperature life test heat pipes. Thermacore, Inc. has carried out several sodium heat pipe life tests to establish long term operating reliability. Four sodium heat pipes have recently demonstrated favorable materials compatibility and heat transport characteristics at high operating temperatures in air over long time periods. A 316L stainless steel heat pipe with a sintered porous nickel wick structure and an integral brazed cartridge heater has successfully operated at 650C to 700C for over 115,000 hours without signs of failure. A second 316L stainless steel heat pipe with a specially-designed Inconel 601 rupture disk and a sintered nickel powder wick has demonstrated over 83,000 hours at 600C to 650C with similar success. A representative one-tenth segment Stirling Space Power Converter heat pipe with an Inconel 718 envelope and a stainless steel screen wick has operated for over 41,000 hours at nearly 700C. A hybrid (i.e. gas-fired and solar) heat pipe with a Haynes 230 envelope and a sintered porous nickel wick structure was operated for about 20,000 hours at nearly 700C without signs of degradation. These life test results collectively have demonstrated the potential for high temperature heat pipes to serve as reliable energy conversion system components for power applications that require long operating lifetime with high reliability. Detailed design specifications, operating history, and test results are described for each of these sodium heat pipes. Lessons learned and future life

  8. A thermosyphon heat pipe cooler for high power LEDs cooling

    NASA Astrophysics Data System (ADS)

    Li, Ji; Tian, Wenkai; Lv, Lucang

    2016-08-01

    Light emitting diode (LED) cooling is facing the challenge of high heat flux more seriously with the increase of input power and diode density. The proposed unique thermosyphon heat pipe heat sink is particularly suitable for cooling of high power density LED chips and other electronics, which has a heat dissipation potential of up to 280 W within an area of 20 mm × 22 mm (>60 W/cm2) under natural air convection. Meanwhile, a thorough visualization investigation was carried out to explore the two phase flow characteristics in the proposed thermosyphon heat pipe. Implementing this novel thermosyphon heat pipe heat sink in the cooling of a commercial 100 W LED integrated chip, a very low apparent thermal resistance of 0.34 K/W was obtained under natural air convection with the aid of the enhanced boiling heat transfer at the evaporation side and the enhanced natural air convection at the condensation side.

  9. Investigation on Multiple-Pulse Propulsion Performance for a Parabolic Nozzle with Inlet Slit

    NASA Astrophysics Data System (ADS)

    Wen, Ming; Hong, Yanji; Song, Junling

    2011-11-01

    The multiple-pulse impulse coupling coefficient Cm is lower than the single pulse one with the same laser parameters. It is always explained that air recovery in nozzle does not work on time. Three kinds of parabolic nozzles are employed to improve air recovery in the experiments and simulation. There exist inlet slits on side wall of them with width of 1 mm, 2 mm, respectively. The curves of thrust and the process of flow fluid field are presented to study the slit effects on Cm under 20 Hz pulse frequency. The results show: an inlet slit can accelerate the air breathing process in the nozzle and Cm for each pulse exhibits a little variation; the lower Cm is obtained due to the increasing energy loss by a larger size slit; the flat-roofed nozzle gets higher Cm than others.

  10. Apparatus for moving a pipe inspection probe through piping

    DOEpatents

    Zollinger, W. Thor; Appel, D. Keith; Lewis, Gregory W.

    1995-01-01

    A method and apparatus for controllably moving devices for cleaning or inspection through piping systems, including piping systems with numerous piping bends therein, by using hydrostatic pressure of a working fluid introduced into the piping system. The apparatus comprises a reservoir or other source for supplying the working fluid to the piping system, a launch tube for admitting the device into the launcher and a reversible, positive displacement pump for controlling the direction and flow rate of the working fluid. The device introduced into the piping system moves with the flow of the working fluid through the piping system. The launcher attaches to the valved ends of a piping system so that fluids in the piping system can recirculate in a closed loop. The method comprises attaching the launcher to the piping system, supplying the launcher with working fluid, admitting the device into the launcher, pumping the working fluid in the direction and at the rate desired so that the device moves through the piping system for pipe cleaning or inspection, removing the device from the launcher, and collecting the working fluid contained in the launcher.

  11. Heat pipes and use of heat pipes in furnace exhaust

    DOEpatents

    Polcyn, Adam D.

    2010-12-28

    An array of a plurality of heat pipe are mounted in spaced relationship to one another with the hot end of the heat pipes in a heated environment, e.g. the exhaust flue of a furnace, and the cold end outside the furnace. Heat conversion equipment is connected to the cold end of the heat pipes.

  12. Apparatus for moving a pipe inspection probe through piping

    DOEpatents

    Zollinger, W.T.; Appel, D.K.; Lewis, G.W.

    1995-07-18

    A method and apparatus are disclosed for controllably moving devices for cleaning or inspection through piping systems, including piping systems with numerous piping bends therein, by using hydrostatic pressure of a working fluid introduced into the piping system. The apparatus comprises a reservoir or other source for supplying the working fluid to the piping system, a launch tube for admitting the device into the launcher and a reversible, positive displacement pump for controlling the direction and flow rate of the working fluid. The device introduced into the piping system moves with the flow of the working fluid through the piping system. The launcher attaches to the valved ends of a piping system so that fluids in the piping system can recirculate in a closed loop. The method comprises attaching the launcher to the piping system, supplying the launcher with working fluid, admitting the device into the launcher, pumping the working fluid in the direction and at the rate desired so that the device moves through the piping system for pipe cleaning or inspection, removing the device from the launcher, and collecting the working fluid contained in the launcher. 8 figs.

  13. Heat Pipe Technology

    NASA Technical Reports Server (NTRS)

    1981-01-01

    The heat pipe, a sealed chamber whose walls are lined with a "wick," a thin capillary network containing a working fluid in liquid form was developed for a heat distribution system for non-rotating satellites. Use of the heat pipe provides a continuous heat transfer mechanism. "Heat tubes" that improve temperature control in plastics manufacturing equipment incorporated the heat pipe technology. James M. Stewart, an independent consultant, patented the heat tubes he developed and granted a license to Kona Corporation. The Kona Nozzle for heaterless injection molding gets heat for its operation from an external source and has no internal heating bands, reducing machine maintenance and also eliminating electrical hazards associated with heater bands. The nozzles are used by Eastman Kodak, Bic Pen Corporation, Polaroid, Tupperware, Ford Motor Company, RCA, and Western Electric in the molding of their products.

  14. Composite drill pipe

    SciTech Connect

    Leslie, James C.; Leslie, II, James C.; Heard, James; Truong, Liem , Josephson; Marvin , Neubert; Hans

    2008-12-02

    A composite pipe segment is formed to include tapered in wall thickness ends that are each defined by opposed frustoconical surfaces conformed for self centering receipt and intimate bonding contact within an annular space between corresponding surfaces of a coaxially nested set of metal end pieces. The distal peripheries of the nested end pieces are then welded to each other and the sandwiched and bonded portions are radially pinned. The composite segment may include imbedded conductive leads and the axial end portions of the end pieces are shaped to form a threaded joint with the next pipe assembly that includes a contact ring in one pipe assembly pierced by a pointed contact in the other to connect the corresponding leads across the joint.

  15. Heat-pipe Earth.

    PubMed

    Moore, William B; Webb, A Alexander G

    2013-09-26

    The heat transport and lithospheric dynamics of early Earth are currently explained by plate tectonic and vertical tectonic models, but these do not offer a global synthesis consistent with the geologic record. Here we use numerical simulations and comparison with the geologic record to explore a heat-pipe model in which volcanism dominates surface heat transport. These simulations indicate that a cold and thick lithosphere developed as a result of frequent volcanic eruptions that advected surface materials downwards. Declining heat sources over time led to an abrupt transition to plate tectonics. Consistent with model predictions, the geologic record shows rapid volcanic resurfacing, contractional deformation, a low geothermal gradient across the bulk of the lithosphere and a rapid decrease in heat-pipe volcanism after initiation of plate tectonics. The heat-pipe Earth model therefore offers a coherent geodynamic framework in which to explore the evolution of our planet before the onset of plate tectonics.

  16. Apparatus for inspecting piping

    DOEpatents

    Zollingger, W.T.; Appel, D.K.; Park, L.R.

    1995-03-21

    An inspection rabbit is described for inspecting piping systems having severe bends therein. The rabbit consists of a flexible, modular body containing a miniaturized eddy current inspection probe, a self-contained power supply for proper operation of the rabbit, an outer surface that allows ease of movement through piping systems and means for transmitting data generated by the inspection device. The body is preferably made of flexible polyvinyl chloride (PVC) tubing or, alternatively, silicone rubber with a shrink wrapping of polytetrafluoroethylene (TEFLON{trademark}). The body is formed to contain the power supply, preferably a plurality of batteries, and a spool of communication wire that connects to a data processing computer external to the piping system. 6 figures.

  17. Apparatus for inspecting piping

    DOEpatents

    Zollingger, W. Thor; Appel, D. Keith; Park, Larry R.

    1995-01-01

    An inspection rabbit for inspecting piping systems having severe bends therein. The rabbit consists of a flexible, modular body containing a miniaturized eddy current inspection probe, a self-contained power supply for proper operation of the rabbit, an outer surface that allows ease of movement through piping systems and means for transmitting data generated by the inspection device. The body is preferably made of flexible polyvinyl chloride (PVC) tubing or, alternatively, silicone rubber with a shrink wrapping of polytetrafluoroethylene (TEFLON.RTM.). The body is formed to contain the power supply, preferably a plurality of batteries, and a spool of communication wire that connects to a data processing computer external to the piping system.

  18. Heat pipe array heat exchanger

    DOEpatents

    Reimann, Robert C.

    1987-08-25

    A heat pipe arrangement for exchanging heat between two different temperature fluids. The heat pipe arrangement is in a ounterflow relationship to increase the efficiency of the coupling of the heat from a heat source to a heat sink.

  19. In Situ Corrosion and Heat Loss Assessment of Two Nonstandard Underground Heat Distribution System Piping Designs

    DTIC Science & Technology

    2011-06-01

    of this specific design consists of a carrier pipe, carrier pipe insulation ( mineral wool ), an annular air space, steel casing, a layer of exterior...excavation site agree with Perma-Pipe “Multi-Therm 500” nominal specs for 10” carrier with 2” mineral wool insulation. 3. Conduit Temperature: Supply...the ASHRAE calculation method or by manufacturer performance claims. MEC is reasonably certain that the mineral wool insulation used by the

  20. Influence of combustion-preheating vitiation on operability of a hypersonic inlet

    NASA Astrophysics Data System (ADS)

    Liu, K.; Zhu, Y.; Gao, W.; Yang, J.; Jin, Y.; Wu, Y.

    2016-11-01

    Vitiation of the test flow with combustion products is inherent in combustion wind tunnels, and its effect on experimental results needs to be clarified. In this study, the influence of air vitiation on the startability and performance of a hypersonic inlet is investigated through two-dimensional (2D) numerical simulation. The study examines the vitiation effects introduced by carbon dioxide and water vapor, on the basis of maintaining the static pressure, static temperature and Mach number of the incoming flow. The starting Mach number limits of the inlet are estimated, and it is found that both of these vitiation components lower the starting limit of the inlet. This suggests that the experimental results acquired by tests in combustion wind tunnels overestimate the startability of an inlet and, therefore, combustion-preheated facilities may not be completely trusted in this respect. Deviations in the inlet performance caused by the vitiation are also detected. These are nevertheless minor as long as the flow is at the same started or unstarted condition. A further analysis reveals that it is mainly the increase in the heat capacity, and the resulting weaker shock/compression waves and shock-wave/boundary-layer interactions that account for the aforementioned effects.

  1. Supersonic Inlet with Pylons Set and Star-Shaped Forebody for Mixing, Combustion and Thrust Enhancement

    NASA Technical Reports Server (NTRS)

    Gilinsky, M.; Gonor, A. L.; Khaikine, V. A.; Blankson, I. M.

    2003-01-01

    Two new approaches are discussed in this paper for application in the Scramjet inlet of an air-breathing propulsion system: 1) In the first approach, the pylon set is installed in the rectangular inlet near the cowl front edge. For a quasi-axisymmetric inlet, a similar set is installed along the Star-shaped forebody axis. This set contains 3 - 4 airfoil-shaped strips or cross-sectional rings depending on the type of inlet. The inlets: rectangular, axisymmetric or star-shaped, are located at different distances from the forebody. Fuel injection takes place through these pylons, which provides for uniform mixing downstream. The locations, sizes and angles of these pylons are very important for efficient application. Optimal values of geometrical parameters were determined from multi-parametric NSE-based numerical simulations of the laminar and turbulent external/internal flows. These simulations have shown significant benefits for mixing, combustion and thrust of the proposed approach by comparison with traditional well-known designs. Experimental tests will be conducted soon at the NASA LaRC and Institute of Mechanics at Moscow State University. Preliminary estimates are very promising.

  2. Numerical analysis of flow features and operation characteristics of a rocket-based combined-cycle inlet in ejector mode

    NASA Astrophysics Data System (ADS)

    Shi, Lei; Liu, Xiaowei; He, Guoqiang; Qin, Fei; Wei, Xianggeng; Yang, Bin; Liu, Jie

    2016-10-01

    A ready-made central strut-based rocket-based combined-cycle (RBCC) engine was numerically investigated in the ejector mode. The flow features in the RBCC inlet and the matching characteristics between the inlet and the embedded rocket during different flight regimes were examined in detail. It was necessary to perform integrated numerical simulations in the ejector mode within considerable pressure far fields around the inlet/exhaust system. The observed flow features and operation characteristics in the RBCC inlet were strongly correlated with the flight conditions, inlet configuration, and operation of the embedded rocket. It was further found that the integrated function status of multiple factors significantly influenced the performance of the RBCC engine in the ejector mode. The two parameters that macroscopically affected the performance most were the air entrainment mass and the drag of the RBCC inlet. To improve these parameters, it is vital to employ an appropriate design of the RBCC inlet and establish the optimal flight trajectory of the flight vehicle.

  3. Dopant-assisted negative photoionization Ion mobility spectrometry coupled with on-line cooling inlet for real-time monitoring H2S concentration in sewer gas.

    PubMed

    Peng, Liying; Jiang, Dandan; Wang, Zhenxin; Hua, Lei; Li, Haiyang

    2016-06-01

    Malodorous hydrogen sulfide (H2S) gas often exists in the sewer system and associates with the problems of releasing the dangerous odor to the atmosphere and causing sewer pipe to be corroded. A simple method is in demand for real-time measuring H2S level in the sewer gas. In this paper, an innovated method based on dopant-assisted negative photoionization ion mobility spectrometry (DANP-IMS) with on-line semiconductor cooling inlet was put forward and successfully applied for the real-time measurement of H2S in sewer gas. The influence of moisture was effectively reduced via an on-line cooling method and a non-equilibrium dilution with drift gas. The limits of quantitation for the H2S in ≥60% relative humidity air could be obtained at ≤79.0ng L(-1) with linear ranges of 129-2064ng L(-1). The H2S concentration in a sewer manhole was successfully determined while its product ions were identified by an ion-mobility time-of-fight mass spectrometry. Finally, the correlation between sewer H2S concentration and the daily routines and habits of residents was investigated through hourly or real-time monitoring the variation of sewer H2S in manholes, indicating the power of this DANP-IMS method in assessing the H2S concentration in sewer system.

  4. Shell-side distribution and the influence of inlet conditions in a model of a disc-and-doughnut heat exchanger

    NASA Astrophysics Data System (ADS)

    Founti, M. A.; Vardis, C.; Whitelaw, J. H.

    1985-09-01

    Measurements of wall pressure and of three orthogonal velocity components with their corresponding fluctuations are reported for two systems of alternating and equi-spaced doughnut and disc baffles axisymmetrically located in a water turbulent pipe flow, simulating the isothermal shell-side flow in shell and tube heat exchangers. The influence of inlet Reynolds number and of asymmetric inlet flow conditions was studied for two geometries. The velocity field was dominated by the pressure gradient and the flow around each individual baffle was influenced by the relative position of its neighbouring baffles.

  5. Shell-side distribution and the influence of inlet conditions in a model of a disc-and-doughnut heat exchanger

    NASA Astrophysics Data System (ADS)

    Founti, M. A.; Vafidis, C.; Whitelaw, J. H.

    Measurements of wall pressure and of three orthogonal velocity components with their corresponding fluctuations are reported for two systems of alternating and equi-spaced doughnut and disc baffles axisymmetrically located in a water turbulent pipe flow, simulating the isothermal shell-side flow in shell and tube heat exchangers. The influence of inlet Reynolds number and of asymmetric inlet flow conditions was studied for two geometries. The velocity field was dominated by the pressure gradients and the flow around each individual baffle was influenced by the relative position of its neighboring baffles.

  6. Design and operation considerations for attic inlets

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Improving energy efficiency and environmental control in poultry facilities is essential for profitability. Increases in energy costs have prompted evaluation of solar energy systems and passive solar systems such as attic inlets have been adopted as a means to reduce fuel usage. Successful implem...

  7. Heat Pipe With Interrupted Slot

    NASA Technical Reports Server (NTRS)

    Brown, Richard F.; Kosson, Robert L.; Edelstein, Fred

    1994-01-01

    Newer version of heat pipe slot interrupted by plug or, if heat pipe is cast, by bridge of heat-pipe material cast integrally across groove. Small barrier assists in priming heat pipe. Vapor and noncondensible gas still accumulates in liquid channel at evaporator before or during startup, but barrier keeps liquid out of small part of slot at bubble. Dry part of slot allows bubble to escape into vapor channel, making room for liquid to move in during startup.

  8. Reusable high-temperature heat pipes and heat pipe panels

    NASA Technical Reports Server (NTRS)

    Camarda, Charles J. (Inventor); Ransone, Philip O. (Inventor)

    1989-01-01

    A reusable, durable heat pipe which is capable of operating at temperatures up to about 3000 F in an oxidizing environment and at temperatures above 3000 F in an inert or vacuum environment is produced by embedding a refractory metal pipe within a carbon-carbon composite structure. A reusable, durable heat pipe panel is made from an array of refractory-metal pipes spaced from each other. The reusable, durable, heat-pipe is employed to fabricate a hypersonic vehicle leading edge and nose cap.

  9. Experimental investigation of coherent structures in turbulent pipe flow using a large-scale pipe flow facility

    NASA Astrophysics Data System (ADS)

    Dennis, David

    2012-11-01

    In recent years it has been shown by various researchers, using either experimental techniques or direct numerical simulations, that coherent structures (i.e. features of the flow that persist in space and time) such as hairpin vortices, vortex packets, and very large scale motions (or superstructures) play an important role in wall-bounded turbulent flows (boundary layers, pipes and channel flows). A large-scale recirculating pipe flow facility at the University of Liverpool has been developed to enable the investigation of large and very large scale coherent motions in turbulent pipe flow. The facility includes a 100mm-diameter working section, consisting of individual modules of precision-bore borosilicate glass tubes each 1.027m long, totalling 22 metres in length. Experimental measurements using high-speed stereoscopic particle image velocimetry at approximately 210 pipe diameters downstream of the inlet are made possible using a unique mechanical arrangement for performing the calibration. Reynolds numbers of up to ReD =105 can be reached when the working fluid is water.

  10. Explosive Welding of Pipes

    NASA Astrophysics Data System (ADS)

    Drennov, Oleg; Drennov, Andrey; Burtseva, Olga

    2013-06-01

    For connection by welding it is suggested to use the explosive welding method. This method is rather new. Nevertheless, it has become commonly used among the technological developments. This method can be advantageous (saving material and physical resources) comparing to its statical analogs (electron-beam welding, argon-arc welding, plasma welding, gas welding, etc.), in particular, in hard-to-reach areas due to their geographic and climatic conditions. Explosive welding of cylindrical surfaces is performed by launching of welded layer along longitudinal axis of construction. During this procedure, it is required to provide reliable resistance against radial convergent strains. The traditional method is application of fillers of pipe cavity, which are dense cylindrical objects having special designs. However, when connecting pipes consecutively in pipelines by explosive welding, removal of the fillers becomes difficult and sometimes impossible. The suggestion is to use water as filler. The principle of non-compressibility of liquid under quasi-dynamic loading is used. In one-dimensional gasdynamic and elastic-plastic calculations we determined non-deformed mass of water (perturbations, which are moving in the axial direction with sound velocity, should not reach the layer end boundaries for 5-7 circulations of shock waves in the radial direction). Linear dimension of the water layer from the zone of pipe coupling along axis in each direction is >= 2R, where R is the internal radius of pipe.

  11. Heat pipe investigations

    NASA Technical Reports Server (NTRS)

    Marshburn, J. P.

    1973-01-01

    Techniques associated with thermal-vacuum and bench testing, along with flight testing of the OAO-C spacecraft heat pipes are outlined, to show that the processes used in heat transfer design and testing are adequate for good performance evaluations.

  12. Small Break Air Ingress Experiment

    SciTech Connect

    Chang Oh; Eung Soo Kim

    2011-09-01

    The small break air-ingress experiment, described in this report, is designed to investigate air-ingress phenomena postulated to occur in pipes in a very high temperature gas-cooled reactor (VHTRs). During this experiment, air-ingress rates were measured for various flow and break conditions through small holes drilled into a pipe of the experimental apparatus. The holes were drilled at right angles to the pipe wall such that a direction vector drawn from the pipe centerline to the center of each hole was at right angles with respect to the pipe centerline. Thus the orientation of each hole was obtained by measuring the included angle between the direction vector of each hole with respect to a reference line anchored on the pipe centerline and pointing in the direction of the gravitational force. Using this reference system, the influence of several important parameters on the air ingress flow rate were measured including break orientation, break size, and flow velocity . The approach used to study the influence of these parameters on air ingress is based on measuring the changes in oxygen concentrations at various locations in the helium flow circulation system as a function of time using oxygen sensors (or detectors) to estimate the air-ingress rates through the holes. The test-section is constructed of a stainless steel pipe which had small holes drilled at the desired locations.

  13. 272. Photocopy of drawing (1983 piping drawing by StearnsRoger Incorporated) ...

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

    272. Photocopy of drawing (1983 piping drawing by Stearns-Roger Incorporated) PIPING INSTALLATION PLANS AND ELEVATIONS FOR ADDITIONAL HELIUM STORAGE TANKS, SHEET 517-P11 - Vandenberg Air Force Base, Space Launch Complex 3, Launch Pad 3 East, Napa & Alden Roads, Lompoc, Santa Barbara County, CA

  14. 266. Photocopy of drawing (1979 piping drawing by StearnsRoger Incorporated) ...

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

    266. Photocopy of drawing (1979 piping drawing by Stearns-Roger Incorporated) PIPING PLAN FOR HELIUM AND NITROGEN PUMPING SYSTEMS, SHEET 501-P17 - Vandenberg Air Force Base, Space Launch Complex 3, Launch Pad 3 East, Napa & Alden Roads, Lompoc, Santa Barbara County, CA

  15. 167. Photocopy of drawing (1979 piping drawing by StearnsRoger Incorporated) ...

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

    167. Photocopy of drawing (1979 piping drawing by Stearns-Roger Incorporated) HELIUM AND NITROGEN PUMPING SYSTEMS PIPING PLAN, SHEET 511-P8 - Vandenberg Air Force Base, Space Launch Complex 3, Launch Pad 3 West, Napa & Alden Roads, Lompoc, Santa Barbara County, CA

  16. 269. Photocopy of drawing (1981 piping drawing by StearnsRoger Incorporated) ...

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

    269. Photocopy of drawing (1981 piping drawing by Stearns-Roger Incorporated) ATLAS H CONVERSION; PLANS, SECTIONS, AND DETAILS FOR FUEL AND NITROGEN PIPING, SHEET 517-P3 - Vandenberg Air Force Base, Space Launch Complex 3, Launch Pad 3 East, Napa & Alden Roads, Lompoc, Santa Barbara County, CA

  17. 271. Photocopy of drawing (1981 piping drawing by StearnsRoger Incorporated) ...

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

    271. Photocopy of drawing (1981 piping drawing by Stearns-Roger Incorporated) PIPING SCHEMATICS FOR THE ATLAS H CONVERSION, SHEET 517-P1 - Vandenberg Air Force Base, Space Launch Complex 3, Launch Pad 3 East, Napa & Alden Roads, Lompoc, Santa Barbara County, CA

  18. 268. Photocopy of drawing (1981 piping drawing by StearnsRoger Incorporated) ...

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

    268. Photocopy of drawing (1981 piping drawing by Stearns-Roger Incorporated) ATLAS H CONVERSION; PLANS, SECTIONS, AND DETAILS FOR THE LIQUID OXYGEN PIPING AND THRUST SECTION HEATER DUCT, SHEET 517-P2 - Vandenberg Air Force Base, Space Launch Complex 3, Launch Pad 3 East, Napa & Alden Roads, Lompoc, Santa Barbara County, CA

  19. 33 CFR 334.1240 - Sinclair Inlet; naval restricted areas.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... ARMY, DEPARTMENT OF DEFENSE DANGER ZONE AND RESTRICTED AREA REGULATIONS § 334.1240 Sinclair Inlet..., longitude 122°37′23″ West on the north shore of Sinclair Inlet; and latitude 47°32′52″ North, longitude 122°36′58″ West, on the south shore of Sinclair Inlet. (2) Area No. 2. That area of Sinclair Inlet to...

  20. Flow Control in a Compact Inlet

    NASA Astrophysics Data System (ADS)

    Vaccaro, John C.

    2011-12-01

    An experimental investigation of flow control, via various control jets actuators, was undertaken to eliminate separation and secondary flows in a compact inlet. The compact inlet studied was highly aggressive with a length-to-diameter ratio of 1.5. A brand new facility was designed and built to enable various actuation methodologies as well as multiple measurement techniques. Techniques included static surface pressure, total pressure, and stereoscopic particle image velocimetry. Experimental data were supplemented with numerical simulations courtesy of Prof. Kenneth Jansen, Dr. Onkar Sahni, and Yi Chen. The baseline flow field was found to be dominated by two massive separations and secondary flow structures. These secondary structures were present at the aerodynamic interface plane in the form of two counter-rotating vortices inducing upwash along centerline. A dominant shedding frequency of 350 Hz was measured both at the aerodynamic interface plane and along the lower surface of the inlet. Flow control experiments started utilizing a pair of control jets placed in streamwise locations where flow was found to separate. Tests were performed for a range of inlet Mach numbers from 0.2 to 0.44. Steady and unsteady static pressure measurements along the upper and lower walls of the duct were performed for various combinations of actuation. The parameters that were tested include the control jets momentum coefficient, their blowing ratio, the actuation frequency, as well as different combinations of jets. It was shown that using mass flux ratio as a criterion to define flow control is not sufficient, and one needs to provide both the momentum coefficient and the blowing ratio to quantify the flow control performance. A detailed study was undertaken on controlling the upstream separation point for an inlet Mach number of 0.44. Similar to the baseline flow field, the flow field associated with the activation of a two-dimensional control jet actuator was dominated by

  1. 49 CFR 178.337-8 - Openings, inlets, and outlets.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... used to transport chlorine. The requirements for inlets and outlets on chlorine cargo tanks are in... equalization of pressure. (b) Inlets and discharge outlets on chlorine tanks. The inlet and discharge outlets on a cargo tank used to transport chlorine must meet the requirements of § 178.337-1(c)(2) and...

  2. 49 CFR 178.337-8 - Openings, inlets, and outlets.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... used to transport chlorine. The requirements for inlets and outlets on chlorine cargo tanks are in... equalization of pressure. (b) Inlets and discharge outlets on chlorine tanks. The inlet and discharge outlets on a cargo tank used to transport chlorine must meet the requirements of § 178.337-1(c)(2) and...

  3. 49 CFR 178.337-8 - Openings, inlets, and outlets.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... used to transport chlorine. The requirements for inlets and outlets on chlorine cargo tanks are in... equalization of pressure. (b) Inlets and discharge outlets on chlorine tanks. The inlet and discharge outlets on a cargo tank used to transport chlorine must meet the requirements of § 178.337-1(c)(2) and...

  4. 49 CFR 178.337-8 - Openings, inlets, and outlets.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... used to transport chlorine. The requirements for inlets and outlets on chlorine cargo tanks are in... equalization of pressure. (b) Inlets and discharge outlets on chlorine tanks. The inlet and discharge outlets on a cargo tank used to transport chlorine must meet the requirements of § 178.337-1(c)(2) and...

  5. 49 CFR 178.337-8 - Openings, inlets, and outlets.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... used to transport chlorine. The requirements for inlets and outlets on chlorine cargo tanks are in... equalization of pressure. (b) Inlets and discharge outlets on chlorine tanks. The inlet and discharge outlets on a cargo tank used to transport chlorine must meet the requirements of § 178.337-1(c)(2) and...

  6. ’E’ SERIES TURBOPUMP INLET STUDIES,

    DTIC Science & Technology

    pipe. Space limitations do not allow this configuration, therefore it was necessary to design an elbow to meet these conditions. The objective was to...obtain pressure drop and velocity profile measurements for two diffuser elbow configurations using water as the flow media; To obtain velocity profile

  7. Influence of inlet conditions on vortex characteristics

    NASA Astrophysics Data System (ADS)

    Essiptchouk, A.

    2011-09-01

    Vortex chambers are normally used for arc stabilization in linear plasma torches. In the present work, the effect of uniformity of the gas inlet channel distribution on the stabilizing characteristics of a swirled flow is studied numerically. The formation of a complex flow pattern with a toroidal recirculating flow area inside the vortex chamber is observed. For some regimes, two local maxima of the tangential velocity are observed in the middle section of the chamber. It is shown that an increment of the number of gas inlet channels leads to a more uniform gas input with disappearance of the second maximum, which increases the velocity amplification coefficient and, correspondingly, results in a better stabilizing effect. The obtained profiles of the radial distribution of the tangential velocity are compared with the results of Oseen's equation for an unconfined vortex.

  8. PROCESS WATER BUILDING, TRA605. AERIAL TAKEN WHILE SEVERAL PIPE TRENCHES ...

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

    PROCESS WATER BUILDING, TRA-605. AERIAL TAKEN WHILE SEVERAL PIPE TRENCHES REMAINED OPEN. CAMERA FACES EASTERLY. NOTE DUAL PIPES BETWEEN REACTOR BUILDING AND NORTH SIDE OF PROCESS WATER BUILDING. PIPING NEAR WORKING RESERVOIR HEADS FOR RETENTION RESERVOIR. PIPE FROM DEMINERALIZER ENTERS MTR FROM NORTH. SEE ALSO TRENCH FOR COOLANT AIR DUCT AT SOUTH SIDE OF MTR AND LEADING TO FAN HOUSE AND STACK. INL NEGATIVE NO. 2966-A. Unknown Photographer, 7/31/1951 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

  9. Analysis, Verification, and Application of Equations and Procedures for Design of Exhaust-pipe Shrouds

    NASA Technical Reports Server (NTRS)

    Ellerbrock, Herman H.; Wcislo, Chester R.; Dexter, Howard E.

    1947-01-01

    Investigations were made to develop a simplified method for designing exhaust-pipe shrouds to provide desired or maximum cooling of exhaust installations. Analysis of heat exchange and pressure drop of an adequate exhaust-pipe shroud system requires equations for predicting design temperatures and pressure drop on cooling air side of system. Present experiments derive such equations for usual straight annular exhaust-pipe shroud systems for both parallel flow and counter flow. Equations and methods presented are believed to be applicable under certain conditions to the design of shrouds for tail pipes of jet engines.

  10. Large Eddy Simulation of Supersonic Inlet Flows

    DTIC Science & Technology

    1998-04-01

    SIMULATION OF SUPERSONIC INLET FLOWS 6. AUTHOR(S) PROF. PARVIZ MOIN PROF. SANJIVA K. LELE 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) STANFORD... Parviz Moin and Sanjiva K. Lele Stanford University Mechanical Engineering, Flow Physics & Computation Division Stanford, CA 94305-3030 Prepared...monitor. I am thankful to Professor Sanjiva Lele and Profes- sor Parviz Moin, and Keith Lucas for useful discussions! I am grateful to Professor Peter

  11. Gasdynamic Inlet Isolation in Rotating Detonation Engine

    DTIC Science & Technology

    2010-12-01

    ISOLATION IN ROTATING DETONATION ENGINE by Wei Han Eugene Lim December 2010 Thesis Co-Advisors: Jose O. Sinibaldi Christopher M. Brophy...COVERED Master’s Thesis 4. TITLE AND SUBTITLE Gasdynamic Inlet Isolation in Rotating Detonation Engine 6. AUTHOR(S) Wei Han Eugene Lim 5. FUNDING...DISTRIBUTION CODE 13. ABSTRACT (maximum 200 words) The Rotating Detonation Engine (RDE) concept represents the next-generation of detonation -based

  12. 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

  13. Investigation of "6X" Scramjet Inlet Configurations

    NASA Technical Reports Server (NTRS)

    Alter, Stephen J.

    2012-01-01

    This work represents an initial attempt to determine what, if any, issues arise from scaling demonstration supersonic combustion scramjets to a flight scale making the engine a viable candidate for both military weapon and civilian access to space applications. The original vehicle sizes tested and flown to date, were designed to prove a concept. With the proven designs, use of the technology for applications as weapon systems or space flight are only possible at six to ten times the original scale. To determine effects of scaling, computations were performed with hypersonic inlets designed to operate a nominal Mach 4 and Mach 5 conditions that are possible within the eight foot high temperature tunnel at NASA Langley Research Center. The total pressure recovery for these inlets is about 70%, while maintaining self start conditions, and providing operable inflow to combustors. Based on this study, the primary scaling effect detected is the strength of a vortex created along the cowl edge causing adverse boundary layer growth in the inlet.

  14. 7. View north at back (canal side) of culvert inlet, ...

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

    7. View north at back (canal side) of culvert inlet, with canal bank completely removed. Background to foreground: back of inlet headwall with tops of high inlet barrels exposed; vertical transition wall between high inlet barrels and low, interior, inlet barrels; tops of low interior barrels; vertical heartening planks and low cutoff wall at site of former canal edge of canal bank; dewatered canal bed and plank sheathing on top of culvert barrels beneath canal bed. - Delaware & Raritan Canal, Ten Mile Run Culvert, 1.5 miles South of Blackwells Road, East Millstone, Somerset County, NJ

  15. DETAIL OF VACUUM PIPE AT BASEMENT LEVEL OF O&C BUILDING, ...

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

    DETAIL OF VACUUM PIPE AT BASEMENT LEVEL OF O&C BUILDING, ALTITUDE CHAMBER R, FACING NORTHEAST - Cape Canaveral Air Force Station, Launch Complex 39, Altitude Chambers, First Street, between Avenue D and Avenue E, Cape Canaveral, Brevard County, FL

  16. DETAIL OF VACUUM PIPE AT 0’0” LEVEL, ALTITUDE CHAMBER R, ...

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

    DETAIL OF VACUUM PIPE AT 0’-0” LEVEL, ALTITUDE CHAMBER R, FACING NORTHEAST - Cape Canaveral Air Force Station, Launch Complex 39, Altitude Chambers, First Street, between Avenue D and Avenue E, Cape Canaveral, Brevard County, FL

  17. VIEW OF PIPES AND RAIL, A/C MECHANICAL EQUIPMENT ROOM, FACING ...

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

    VIEW OF PIPES AND RAIL, A/C MECHANICAL EQUIPMENT ROOM, FACING SOUTHEAST - Cape Canaveral Air Force Station, Launch Complex 34, Operations Support Building, Freedom Road, Southwest of Launch Stand CX-34, Cape Canaveral, Brevard County, FL

  18. Drill pipe protector development

    SciTech Connect

    Thomerson, C.; Kenne, R.; Wemple, R.P.

    1996-03-01

    The Geothermal Drilling Organization (GDO), formed in the early 1980s by the geothermal industry and the U.S. Department of Energy (DOE) Geothermal Division, sponsors specific development projects to advance the technologies used in geothermal exploration, drilling, and production phases. Individual GDO member companies can choose to participate in specific projects that are most beneficial to their industry segment. Sandia National Laboratories is the technical interface and contracting office for the DOE in these projects. Typical projects sponsored in the past have included a high temperature borehole televiewer, drill bits, muds/polymers, rotary head seals, and this project for drill pipe protectors. This report documents the development work of Regal International for high temperature geothermal pipe protectors.

  19. Entrainment by turbulent jets issuing from sharp-edged inlet round nozzles

    NASA Astrophysics Data System (ADS)

    Trabold, T. A.; Essen, E. B.; Obot, N. T.

    Experiments were carried out to determine entrainment rates by turbulent air jets generated with square-edged inlet round nozzles. A parametric study was made which included the effects of Reynolds number, nozzle length, partial confinement and geometry of the jet plenum chamber. Measurements were made for the region extending from the nozzle exit to 24 jet hole diameters downstream. There is a large difference in entrainment rate between jets generated with relatively short nozzles and those discharged through long tubes.

  20. Heat Pipe Systems

    NASA Technical Reports Server (NTRS)

    1988-01-01

    Solar Fundamentals, Inc.'s hot water system employs space-derived heat pipe technology. It is used by a meat packing plant to heat water for cleaning processing machinery. Unit is complete system with water heater, hot water storage, electrical controls and auxiliary components. Other than fans and a circulating pump, there are no moving parts. System's unique design eliminates problems of balancing, leaking, corroding, and freezing.

  1. Variable geometry for supersonic mixed-compression inlets

    NASA Technical Reports Server (NTRS)

    Sorensen, N. E.; Latham, E. A.; Smeltzer, D. B.

    1974-01-01

    Study of two-dimensional and axisymmetric supersonic mixed-compression inlet systems has shown that the geometry of both systems can be varied to provide adequate transonic airflow to satisfy the airflow demand of most jet engines. Collapsing geometry systems for both types of inlet systems provide a generous amount of transonic airflow for any design Mach number inlet system. However, the mechanical practicality of collapsing centerbodies for axisymmetric inlet systems is doubtful. Therefore, translating centerbody axisymmetric inlets with auxiliary airflow systems to augment the transonic airflow capability are an attractive alternative. Estimates show that the capture mass-flow ratio at Mach number 1.0 can be increased approximately 0.20 for a very short axisymmetric inlet system designed for Mach number 2.37. With this increase in mass-flow ratio, even variable-cycle engine transonic airflow demand can be matched without oversizing the inlet at the design Mach number.

  2. Underground pipeline laying using the pipe-in-pipe system

    NASA Astrophysics Data System (ADS)

    Antropova, N.; Krets, V.; Pavlov, M.

    2016-09-01

    The problems of resource saving and environmental safety during the installation and operation of the underwater crossings are always relevant. The paper describes the existing methods of trenchless pipeline technology, the structure of multi-channel pipelines, the types of supporting and guiding systems. The rational design is suggested for the pipe-in-pipe system. The finite element model is presented for the most dangerous sections of the inner pipes, the optimum distance is detected between the roller supports.

  3. Impervious surfaces and sewer pipe effects on stormwater runoff temperature

    NASA Astrophysics Data System (ADS)

    Sabouri, F.; Gharabaghi, B.; Mahboubi, A. A.; McBean, E. A.

    2013-10-01

    The warming effect of the impervious surfaces in urban catchment areas and the cooling effect of underground storm sewer pipes on stormwater runoff temperature are assessed. Four urban residential catchment areas in the Cities of Guelph and Kitchener, Ontario, Canada were evaluated using a combination of runoff monitoring and modelling. The stormwater level and water temperature were monitored at 10 min interval at the inlet of the stormwater management ponds for three summers 2009, 2010 and 2011. The warming effect of the ponds is also studied, however discussed in detail in a separate paper. An artificial neural network (ANN) model for stormwater temperature was trained and validated using monitoring data. Stormwater runoff temperature was most sensitive to event mean temperature of the rainfall (EMTR) with a normalized sensitivity coefficient (Sn) of 1.257. Subsequent levels of sensitivity corresponded to the longest sewer pipe length (LPL), maximum rainfall intensity (MI), percent impervious cover (IMP), rainfall depth (R), initial asphalt temperature (AspT), pipe network density (PND), and rainfall duration (D), respectively. Percent impervious cover of the catchment area (IMP) was the key parameter that represented the warming effect of the paved surfaces; sensitivity analysis showed IMP increase from 20% to 50% resulted in runoff temperature increase by 3 °C. The longest storm sewer pipe length (LPL) and the storm sewer pipe network density (PND) are the two key parameters that control the cooling effect of the underground sewer system; sensitivity analysis showed LPL increase from 345 to 966 m, resulted in runoff temperature drop by 2.5 °C.

  4. Heat pipe technology: A bibliography with abstracts

    NASA Technical Reports Server (NTRS)

    1971-01-01

    The annual supplement on heat pipe technology for 1971 is presented. The document contains 101 references with abstracts and 47 patents. The subjects discussed are: (1) heat pipe applications, (2) heat pipe theory, (3) design, development, and fabrication of heat pipes, (4) testing and operation, (5) subject and author index, and (6) heat pipe related patents.

  5. 259. Photocopy of drawing (1976 piping drawing by the Space ...

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

    259. Photocopy of drawing (1976 piping drawing by the Space and Missile Test Center, VAFB, USAF) PLANS, SECTIONS, AND DETAILS OF THE DELUGE WATER SYSTEM FOR THE FLAME BUCKET, SHEET P-17 - Vandenberg Air Force Base, Space Launch Complex 3, Launch Pad 3 East, Napa & Alden Roads, Lompoc, Santa Barbara County, CA

  6. 182. Photocopy of drawing (1972 piping drawing by the Ralph ...

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

    182. Photocopy of drawing (1972 piping drawing by the Ralph M. Parsons Company) PLAN FOR THE LIQUID NITROGEN STORAGE AND BOOSTER CONTROL ROOM FOR THE LSB (BLDG. 770), SHEET P-12 - Vandenberg Air Force Base, Space Launch Complex 3, Launch Pad 3 West, Napa & Alden Roads, Lompoc, Santa Barbara County, CA

  7. 238. Photocopy of drawing (1958 piping drawing by the Ralph ...

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

    238. Photocopy of drawing (1958 piping drawing by the Ralph M. Parsons Company) NITROGEN FLOW DIAGRAM FOR THE LSB, SHEET P3 OF 36 - Vandenberg Air Force Base, Space Launch Complex 3, Launch Pad 3 East, Napa & Alden Roads, Lompoc, Santa Barbara County, CA

  8. 236. Photocopy of drawing (1958 piping drawing by the Ralph ...

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

    236. Photocopy of drawing (1958 piping drawing by the Ralph M. Parsons Company) SECTIONS AND DETAILS FOR THE FUEL, HELIUM, AND NITROGEN STORAGE AREA FOR THE LSB, SHEET P14 OF 36 - Vandenberg Air Force Base, Space Launch Complex 3, Launch Pad 3 East, Napa & Alden Roads, Lompoc, Santa Barbara County, CA

  9. 235. Photocopy of drawing (1958 piping drawing by the Ralph ...

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

    235. Photocopy of drawing (1958 piping drawing by the Ralph M. Parsons Company) PLAN FOR THE FUEL, HELIUM, AND NITROGEN STORAGE AREA FOR THE LSB, SHEET P13 OF 36 - Vandenberg Air Force Base, Space Launch Complex 3, Launch Pad 3 East, Napa & Alden Roads, Lompoc, Santa Barbara County, CA

  10. 264. Photocopy of drawing (1977 piping drawing by the Space ...

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

    264. Photocopy of drawing (1977 piping drawing by the Space and Missile Test Center, VAFB, USAF) NITROGEN AND HELIUM PUMPING SYSTEMS INSTALLATION SITE PLAN AND DETAILS, SHEET 3 OF 9 - Vandenberg Air Force Base, Space Launch Complex 3, Launch Pad 3 East, Napa & Alden Roads, Lompoc, Santa Barbara County, CA

  11. 243. Photocopy of drawing (1958 piping drawing by the Ralph ...

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

    243. Photocopy of drawing (1958 piping drawing by the Ralph M. Parsons Company) WATER SYSTEMS FLOW DIAGRAM FOR THE LSB, SHEET P6 OF 36 - Vandenberg Air Force Base, Space Launch Complex 3, Launch Pad 3 East, Napa & Alden Roads, Lompoc, Santa Barbara County, CA

  12. 240. Photocopy of drawing (1958 piping drawing by the Ralph ...

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

    240. Photocopy of drawing (1958 piping drawing by the Ralph M. Parsons Company) HELIUM FLOW DIAGRAM FOR THE LSB, SHEET P4 OF 36 - Vandenberg Air Force Base, Space Launch Complex 3, Launch Pad 3 East, Napa & Alden Roads, Lompoc, Santa Barbara County, CA

  13. 237. Photocopy of drawing (1958 piping drawing by the Ralph ...

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

    237. Photocopy of drawing (1958 piping drawing by the Ralph M. Parsons Company) BOOSTER FUEL SYSTEM FLOW DIAGRAM FOR THE LSB, SHEET P1 OF 36 - Vandenberg Air Force Base, Space Launch Complex 3, Launch Pad 3 East, Napa & Alden Roads, Lompoc, Santa Barbara County, CA

  14. 241. Photocopy of drawing (1958 piping drawing by the Ralph ...

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

    241. Photocopy of drawing (1958 piping drawing by the Ralph M. Parsons Company) VEHICLE SERVICING SYSTEMS FLOW DIAGRAM FOR THE LSB, SHEET P5 OF 36 - Vandenberg Air Force Base, Space Launch Complex 3, Launch Pad 3 East, Napa & Alden Roads, Lompoc, Santa Barbara County, CA

  15. Heat pipes. Citations from the NTIS data base

    NASA Astrophysics Data System (ADS)

    Reed, W. E.

    1980-04-01

    Theory, design, fabrication, testing, and operation of heat pipes are presented in these Federally-sponsored research reports. Applications are described in the areas of heating and air conditioning, power generation, electronics cooling, spacecraft, nuclear reactors, cooling engines, and thermodynamics. This updated bibliography contains 247 abstracts, none of which are new entries to the previous edition.

  16. Heat pipes. Citations from the NTIS data base

    NASA Astrophysics Data System (ADS)

    Reed, W. E.

    1980-04-01

    Theory, design, fabrication, testing, and operation of heat pipes are presented in these Federally sponsored research reports. Applications are described in the areas of heating and air conditioning, power generation, electronics cooling, spacecraft, nuclear reactors, cooling engines, and thermodynamics. This updated bibliography contains 70 abstracts, all of which are new entries to the previous edition.

  17. 46 CFR 95.16-60 - System piping installation testing.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... piping installation testing. (a) Halocarbon systems. A pressure test using the extinguishing agent, air...-minute period must not exceed a pressure drop of 10 percent of the test pressure. (2) Individual branch... must be tested as described in paragraph (a)(1) of this section. (b) Inert gas systems. A pressure...

  18. 46 CFR 95.16-60 - System piping installation testing.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... piping installation testing. (a) Halocarbon systems. A pressure test using the extinguishing agent, air...-minute period must not exceed a pressure drop of 10 percent of the test pressure. (2) Individual branch... must be tested as described in paragraph (a)(1) of this section. (b) Inert gas systems. A pressure...

  19. 46 CFR 95.16-60 - System piping installation testing.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... piping installation testing. (a) Halocarbon systems. A pressure test using the extinguishing agent, air...-minute period must not exceed a pressure drop of 10 percent of the test pressure. (2) Individual branch... must be tested as described in paragraph (a)(1) of this section. (b) Inert gas systems. A pressure...

  20. 8. Exterior view, showing tank and associated piping adjacent to ...

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

    8. Exterior view, showing tank and associated piping adjacent to Test Cell 6, Systems Integration Laboratory Building (T-28), looking south. - Air Force Plant PJKS, Systems Integration Laboratory, Systems Integration Laboratory Building, Waterton Canyon Road & Colorado Highway 121, Lakewood, Jefferson County, CO

  1. 12. Exterior view, showing tank and piping associated with Test ...

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

    12. Exterior view, showing tank and piping associated with Test Cell 7, Systems Integration Laboratory Building (T-28), looking west. - Air Force Plant PJKS, Systems Integration Laboratory, Systems Integration Laboratory Building, Waterton Canyon Road & Colorado Highway 121, Lakewood, Jefferson County, CO

  2. 3. View, piping and stack associated with the oxidizer vault ...

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

    3. View, piping and stack associated with the oxidizer vault storage area in foreground with Systems Integration Laboratory (T-28) in background, looking northwest. - Air Force Plant PJKS, Systems Integration Laboratory, Waterton Canyon Road & Colorado Highway 121, Lakewood, Jefferson County, CO

  3. 234. Photocopy of drawing (1958 piping drawing by the Ralph ...

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

    234. Photocopy of drawing (1958 piping drawing by the Ralph M. Parsons Company) BOOSTER LIQUID OXYGEN SYSTEM FLOW DIAGRAM FOR THE LSB, SHEET P2 OF 36 - Vandenberg Air Force Base, Space Launch Complex 3, Launch Pad 3 East, Napa & Alden Roads, Lompoc, Santa Barbara County, CA

  4. 232. Photocopy of drawing (1958 piping drawing by the Ralph ...

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

    232. Photocopy of drawing (1958 piping drawing by the Ralph M. Parsons Company) PLAN FOR THE LIQUID AND GASEOUS OXYGEN STORAGE AREA IN THE LSB, SHEET P17 OF 36 - Vandenberg Air Force Base, Space Launch Complex 3, Launch Pad 3 East, Napa & Alden Roads, Lompoc, Santa Barbara County, CA

  5. 179. Photocopy of drawing (1972 piping drawing by the Ralph ...

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

    179. Photocopy of drawing (1972 piping drawing by the Ralph M. Parsons Company) LIQUID OXYGEN STORAGE PLAN FOR THE LSB (BLDG. 770), SHEET P-7 - Vandenberg Air Force Base, Space Launch Complex 3, Launch Pad 3 West, Napa & Alden Roads, Lompoc, Santa Barbara County, CA

  6. 233. Photocopy of drawing (1958 piping drawing by the Ralph ...

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

    233. Photocopy of drawing (1958 piping drawing by the Ralph M. Parsons Company) PLAN FOR THE LIQUID OXYGEN CONTROL ROOM FOR THE LSB, SHEET P16 OF 36 - Vandenberg Air Force Base, Space Launch Complex 3, Launch Pad 3 East, Napa & Alden Roads, Lompoc, Santa Barbara County, CA

  7. 256. Photocopy of drawing (1975 piping drawing by the Ralph ...

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

    256. Photocopy of drawing (1975 piping drawing by the Ralph M. Parsons Company) LIQUID OXYGEN FLOW DIAGRAM FOR THE LSB AREA, SHEET P-2 - Vandenberg Air Force Base, Space Launch Complex 3, Launch Pad 3 East, Napa & Alden Roads, Lompoc, Santa Barbara County, CA

  8. 180. Photocopy of drawing (1972 piping drawing by the Ralph ...

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

    180. Photocopy of drawing (1972 piping drawing by the Ralph M. Parsons Company) LIQUID OXYGEN FLOW DIAGRAM FOR THE LSB (BLDG. 770), SHEET P-2 - Vandenberg Air Force Base, Space Launch Complex 3, Launch Pad 3 West, Napa & Alden Roads, Lompoc, Santa Barbara County, CA

  9. 222. Photocopy of drawing (1958 piping drawing by the Ralph ...

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

    222. Photocopy of drawing (1958 piping drawing by the Ralph M. Parsons Company) VEHICLE SERVICING SYSTEMS SECTIONS FOR THE UMBILICAL MAST, SHEET P24 OF 36 - Vandenberg Air Force Base, Space Launch Complex 3, Launch Pad 3 East, Napa & Alden Roads, Lompoc, Santa Barbara County, CA

  10. Noise radiation directivity from a wind-tunnel inlet with inlet vanes and duct wall linings

    NASA Technical Reports Server (NTRS)

    Soderman, P. T.; Phillips, J. D.

    1986-01-01

    The acoustic radiation patterns from a 1/15th scale model of the Ames 80- by 120-Ft Wind Tunnel test section and inlet have been measured with a noise source installed in the test section. Data were acquired without airflow in the duct. Sound-absorbent inlet vanes oriented parallel to each other, or splayed with a variable incidence relative to the duct long axis, were evaluated along with duct wall linings. Results show that splayed vans tend to spread the sound to greater angles than those measured with the open inlet. Parallel vanes narrowed the high-frequency radiation pattern. Duct wall linings had a strong effect on acoustic directivity by attenuating wall reflections. Vane insertion loss was measured. Directivity results are compared with existing data from square ducts. Two prediction methods for duct radiation directivity are described: one is an empirical method based on the test data, and the other is a analytical method based on ray acoustics.

  11. Experimenting with a ``Pipe'' Whistle

    NASA Astrophysics Data System (ADS)

    Stafford, Olga

    2012-04-01

    A simple pipe whistle can be made using pieces of PVC pipe. The whistle can be used to measure the resonant frequencies of open or closed pipes. A slightly modified version of the device can be used to also investigate the interesting dependence of the sound frequencies produced on the orifice-to-edge distance. The pipe whistle described here allows students in a physics of music or introductory physics course to study an example of an "edge tone" device that produces discrete sound frequencies. From their textbooks, students likely know about standing waves produced by pipes or strings, as well as the resonant frequencies for open and closed pipes. To go a bit further, they can also learn how the frequency of the sound wave depends on the orifice-to-edge distance of the wind instrument.

  12. Radiation crosslinked plasticized PVC - pipes

    NASA Astrophysics Data System (ADS)

    Hell, Z.; Ravlić, M.; Bogdanović, Lj.; Maleš, J.; Dvornik, I.; Ranogajec, F.; Ranogajec, M.; Tudorić-Ghemo, J.

    The efficiency of polyfunctional monomers triallyl cyanurate, allyl methacrylate, diallyl phtalate, 2-ethyl-2(hydroxy-methyl)-propanediol-(1,3) trimethacrylate, divinyl benzene and ethylene glycol dimethacrylate in radiation crosslinking of PVC was investigated. Patterns of pipes were produced and irradiated with gamma rays. The resistance to internal pressure of crosslinked PVC pipes was measured at 80°C and compared with resistance of unirradiated PVC pipes.

  13. Insulating Cryogenic Pipes With Frost

    NASA Technical Reports Server (NTRS)

    Stephenson, J. G.; Bova, J. A.

    1985-01-01

    Crystallized water vapor fills voids in pipe insulation. Small, carefully controlled amount of water vapor introduced into dry nitrogen gas before it enters aft fuselage. Vapor freezes on pipes, filling cracks in insulation. Ice prevents gaseous nitrogen from condensing on pipes and dripping on structure, in addition to helping to insulate all parts. Industrial applications include large refrigeration plants or facilities that use cryogenic liquids.

  14. Characterisation and airborne deployment of a new counterflow virtual impactor inlet

    NASA Astrophysics Data System (ADS)

    Shingler, T.; Dey, S.; Sorooshian, A.; Brechtel, F. J.; Wang, Z.; Metcalf, A.; Coggon, M.; Mülmenstädt, J.; Russell, L. M.; Jonsson, H. H.; Seinfeld, J. H.

    2012-06-01

    A new counterflow virtual impactor (CVI) inlet is introduced with details of its design, laboratory characterisation tests and deployment on an aircraft during the 2011 Eastern Pacific Emitted Aerosol Cloud Experiment (E-PEACE). The CVI inlet addresses three key issues in previous designs; in particular, the inlet operates with: (i) negligible organic contamination; (ii) a significant sample flow rate to downstream instruments (∼15 l min-1) that reduces the need for dilution; and (iii) a high level of accessibility to the probe interior for cleaning. Wind tunnel experiments characterised the cut size of sampled droplets and the particle size-dependent transmission efficiency in various parts of the probe. For a range of counter-flow rates and air velocities, the measured cut size was between 8.7-13.1 μm. The mean percentage error between cut size measurements and predictions from aerodynamic drag theory is 1.7%. The CVI was deployed on the Center for Interdisciplinary Remotely Piloted Aircraft Studies (CIRPAS) Twin Otter for thirty flights during E-PEACE to study aerosol-cloud-radiation interactions off the central coast of California in July and August 2011. Results are reported to assess the performance of the inlet including comparisons of particle number concentration downstream of the CVI and cloud drop number concentration measured by two independent aircraft probes. Measurements downstream of the CVI are also examined from one representative case flight coordinated with shipboard-emitted smoke that was intercepted in cloud by the Twin Otter.

  15. Characterization and airborne deployment of a new counterflow virtual impactor inlet

    NASA Astrophysics Data System (ADS)

    Shingler, T.; Dey, S.; Sorooshian, A.; Brechtel, F. J.; Wang, Z.; Metcalf, A.; Coggon, M.; Mülmenstädt, J.; Russell, L. M.; Jonsson, H. H.; Seinfeld, J. H.

    2012-02-01

    A new counterflow virtual impactor (CVI) inlet is introduced with details of its design, laboratory characterization tests, and deployment on an aircraft during the 2011 Eastern Pacific Emitted Aerosol Cloud Experiment (E-PEACE). The CVI inlet addresses three key issues in previous designs; in particular, the inlet operates with: (i) negligible organic contamination; (ii) a significant sample flow rate to downstream instruments (~15 l min-1) that reduces the need for dilution; and (iii) a high level of accessibility to the probe interior for cleaning. Wind tunnel experiments characterized the cut size of sampled droplets and the particle size-dependent transmission efficiency in various parts of the probe. For a range of counter-flow rates and air velocities, the measured cut size was between 8.7-13.1 μm. The percentage error between cut size measurements and predictions from aerodynamic drag theory are less than 13%. The CVI was deployed on the Center for Interdisciplinary Remotely-Piloted Aircraft Studies (CIRPAS) Twin Otter for thirty flights during E-PEACE to study aerosol-cloud-radiation interactions off the central coast of California between July and August 2011. Results are reported to assess the performance of the inlet including comparisons of particle number concentration downstream of the CVI and cloud drop number concentration measured by two independent aircraft probes. Measurements downstream the CVI are also examined from one representative case flight coordinated with shipboard-emitted smoke that was intercepted in cloud by the Twin Otter.

  16. Thermostructural applications of heat pipes

    NASA Technical Reports Server (NTRS)

    Peeples, M. E.; Reeder, J. C.; Sontag, K. E.

    1979-01-01

    The feasibility of integrating heat pipes in high temperature structure to reduce local hot spot temperature was evaluated for a variety of hypersonic aerospace vehicles. From an initial list of twenty-two potential applications, the single stage to orbit wing leading edge showed the greatest promise and was selected for preliminary design of an integrated heat pipe thermostructural system. The design consisted of a Hastelloy X assembly with sodium heat pipe passages aligned normal to the wing leading edge. A d-shaped heat pipe cross section was determined to be optimum from the standpoint of structural weight.

  17. Cryogenic Heat Pipe Experiment (CRYOHP)

    NASA Technical Reports Server (NTRS)

    Mcintosh, Roy

    1992-01-01

    The objective of the CRYOHP experiment is to conduct a shuttle experiment that demonstrates the reliable operation of two oxygen heat pipes in microgravity. The experiment will perform the following tasks: (1) demonstrate startup of the pipes from the supercritical state; (2) measure the heat transport capacity of the pipes; (3) measure evaporator and condenser film coefficients; and (4) work shuttle safety issues. The approach for the experiment is as follows: (1) fly two axially grooved oxygen heat pipes attached to mechanical stirling cycle tactical coolers; (2) integrate experiment in hitch-hiker canister; and (3) fly on shuttle and control from ground.

  18. Mach 4 Performance of a Fixed-Geometry Hypersonic Inlet with Rectangular-to-Elliptical Shape Transition

    NASA Technical Reports Server (NTRS)

    Smart, Michael K.; Trexler, Carl A.

    2003-01-01

    Wind-tunnel testing of a hypersonic inlet with rectangular-to-elliptical shape transition has been conducted at Mach 4.0. These tests were performed to investigate the starting and back-pressure limits of this fixed-geometry inlet at conditions well below the Mach 5.7 design point. Results showed that the inlet required side spillage holes in order to self-start at Mach 4.0. Once started, the inlet generated a compression ratio of 12.6, captured almost 80% of available air and withstood a back-pressure ratio of 30.3 relative to tunnel static pressure. The spillage penalty for self-starting was estimated to be 4% of available air. These experimental results, along with previous experimental results at Mach 6.2 indicate that fixed-geometry inlets with rectangular-to-elliptical shape transition are a viable configuration for airframe-integrated scramjets that operate over a significant Mach number range. Nomenclature

  19. Investigation of REST-Class Hypersonic Inlet Designs

    NASA Technical Reports Server (NTRS)

    Gollan, Rowan; Ferlemann, Paul G.

    2011-01-01

    Rectangular-to-elliptical shape-transition (REST) inlets are of interest for use on scramjet engines because they are efficient and integrate well with the forebody of a planar vehicle. The classic design technique by Smart for these inlets produces an efficient inlet but the complex three-dimensional viscous effects are only approximately included. Certain undesirable viscous features often occur in these inlets. In the present work, a design toolset has been developed which allows for rapid design of REST-class inlet geometries and the subsequent Navier-Stokes analysis of the inlet performance. This gives the designer feedback on the complex viscous effects at each design iteration. This new tool is applied to design an inlet for on-design operation at Mach 8. The tool allows for rapid investigation of design features that was previously not possible. The outcome is that the inlet shape can be modified to affect aspects of the flow field in a positive way. In one particular example, the boundary layer build-up on the bodyside of the inlet was reduced by 20% of the thickness associated with the classically designed inlet shape.

  20. A Visualization Study of Wall Layer of Swirling Turbulent Pipe Flow

    NASA Astrophysics Data System (ADS)

    Malek, Meriam; Hager, Rachael; Savas, Omer

    2014-11-01

    The streaky vortical structure of the viscous sublayer of a turbulent boundary layer is well known. Turbulent flows in pipes also exhibit similar structures. The effect of swirl on that structure is the subject matter of this study. The experiments are conducted in water in a 5-cm diameter clear cast-acrylic pipe at Reynolds numbers up to 80,000. Initial geometric swirl angles up to 60° at the wall are generated by placing 3D printed inserts at the inlet of the pipe. Flows are visualized using reflective flakes of size distribution 10-80 μm under diffuse illumination. Flows are recorded at high framing rates. After preprocessing, the streaky structure is quantified by using autocorrelation of the images. Lateral spacing and longitudinal length scales are extracted. Also studied is the decay of the swirl angle and its influence of the wall structure. Undergraduate Researcher.

  1. Cesium heat-pipe thermostat

    SciTech Connect

    Wu, F.; Song, D.; Sheng, K.; Wu, J.; Yi, X.; Yu, Z.

    2013-09-11

    In this paper the authors report a newly developed Cesium Heat-Pipe Thermostat (Cs HPT) with the operation range of 400 °C to 800 °C. The working medium is cesium (Cs) of 99.98% purity and contains no radioisotope. A Cs filing device is developed which can prevent Cs being in contact with air. The structural material is stainless steel. A 5000 h test has been made to confirm the compatibility between cesium and stainless steel. The Cs HPT has several thermometer wells of 220mm depth with different diameters for different sizes of thermometers. The temperature uniformity of the Cs HPT is 0.06 °C to 0.20 °C. A precise temperature controller is used to ensure the temperature fluctuation within ±0.03 °C. The size of Cs HPT is 380mm×320mm×280mm with foot wheels for easy moving. The thermostat has been successfully used for the calibration of industrial platinum resistance thermometers and thermocouples.

  2. Heat Rejection from a Variable Conductance Heat Pipe Radiator Panel

    NASA Technical Reports Server (NTRS)

    Jaworske, D. A.; Gibson, M. A.; Hervol, D. S.

    2012-01-01

    A titanium-water heat pipe radiator having an innovative proprietary evaporator configuration was evaluated in a large vacuum chamber equipped with liquid nitrogen cooled cold walls. The radiator was manufactured by Advanced Cooling Technologies, Inc. (ACT), Lancaster, PA, and delivered as part of a Small Business Innovative Research effort. The radiator panel consisted of five titanium-water heat pipes operating as thermosyphons, sandwiched between two polymer matrix composite face sheets. The five variable conductance heat pipes were purposely charged with a small amount of non-condensable gas to control heat flow through the condenser. Heat rejection was evaluated over a wide range of inlet water temperature and flow conditions, and heat rejection was calculated in real-time utilizing a data acquisition system programmed with the Stefan-Boltzmann equation. Thermography through an infra-red transparent window identified heat flow across the panel. Under nominal operation, a maximum heat rejection value of over 2200 Watts was identified. The thermal vacuum evaluation of heat rejection provided critical information on understanding the radiator s performance, and in steady state and transient scenarios provided useful information for validating current thermal models in support of the Fission Power Systems Project.

  3. Air velocity distributions inside tree canopies from a variable-rate air-assisted sprayer

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A variable-rate, air assisted, five-port sprayer had been in development to achieve variable discharge rates of both liquid and air. To verify the variable air rate capability by changing the fan inlet diameter of the sprayer, air jet velocities impeded by plant canopies were measured at various loc...

  4. Large-bore pipe decontamination

    SciTech Connect

    Ebadian, M.A.

    1998-01-01

    The decontamination and decommissioning (D and D) of 1200 buildings within the US Department of Energy-Office of Environmental Management (DOE-EM) Complex will require the disposition of miles of pipe. The disposition of large-bore pipe, in particular, presents difficulties in the area of decontamination and characterization. The pipe is potentially contaminated internally as well as externally. This situation requires a system capable of decontaminating and characterizing both the inside and outside of the pipe. Current decontamination and characterization systems are not designed for application to this geometry, making the direct disposal of piping systems necessary in many cases. The pipe often creates voids in the disposal cell, which requires the pipe to be cut in half or filled with a grout material. These methods are labor intensive and costly to perform on large volumes of pipe. Direct disposal does not take advantage of recycling, which could provide monetary dividends. To facilitate the decontamination and characterization of large-bore piping and thereby reduce the volume of piping required for disposal, a detailed analysis will be conducted to document the pipe remediation problem set; determine potential technologies to solve this remediation problem set; design and laboratory test potential decontamination and characterization technologies; fabricate a prototype system; provide a cost-benefit analysis of the proposed system; and transfer the technology to industry. This report summarizes the activities performed during fiscal year 1997 and describes the planned activities for fiscal year 1998. Accomplishments for FY97 include the development of the applicable and relevant and appropriate regulations, the screening of decontamination and characterization technologies, and the selection and initial design of the decontamination system.

  5. Deployable Pipe-Z

    NASA Astrophysics Data System (ADS)

    Zawidzki, Machi

    2016-10-01

    This paper presents a concept of deployable Pipe-Z (dPZ): a modular structural system which takes advantage of the robustness of rigid-panel mechanism and allows to create free-form links which are also reconfigurable and deployable. The concept presented can be applied for building habitats and infrastructures for human exploration of oceans and outer space. dPZ structures can adapt to changing requirements e.g. mission objectives, crew condition and technological developments. Furthermore, such lightweight and adaptable structural concept can assist in sustainable exploration development. After brief introduction, the concept of Pipe-Z (PZ) is presented. Next, the reconfigurability of PZ is explained and illustrated with continuous and collision-free transition from a PZ forming a Trefoil knot to a Figure-eight knot. The following sections introduce, explain and illustrate the folding mechanism of a single foldable Pipe-Z module (fPZM) and entire dPZ structure. The latter is illustrated with asynchronous (delayed) unfolding of a relatively complex Unknot. Several applications of PZ are suggested, namely for underwater and deep-space and surface habitats, for permanent, but in particular, temporary or emergency passages. As an example, a scenario of a failure of one of the modules of the International Space Station is presented where a rigid structure of 40 fPZMs bypasses the "dead link". A low-fidelity prototype of a 6-module octagonal dPZ is presented; several folding schemes including concentric toric rings are demonstrated. Practical issues of pressurization and packing are briefly discussed.

  6. Ceramic heat pipe wick

    NASA Technical Reports Server (NTRS)

    Seidenberg, Benjamin (Inventor); Swanson, Theodore (Inventor)

    1989-01-01

    A wick for use in a capillary loop pump heat pipe is disclosed. The wick material is an essentially uniformly porous, permeable, open-cell, silicon dioxide/aluminum oxide inorganic ceramic foam having a silica fiber ratio, by weight, of about 78 to 22, respectively, a density of 6 lbs/cu ft, and an average pore size of less than 5 microns. A representative material having these characteristics is Lockheed Missile and Space Company, Inc.'s HTP 6-22. This material is fully compatible with the freons and anhydrous ammonia and allows for the use of these very efficient working fluids, and others, in capillary loops.

  7. Polymeric heat pipe wick

    NASA Astrophysics Data System (ADS)

    Seidenberg, Benjamin

    1988-08-01

    A wick for use in a capillary loop pump heat pipe is described. The wick material is an essentially uniformly porous, permeable, open-cell, polyethylene thermoplastic foam having an ultrahigh average molecular weight of from approximately 1 to 5 million, and an average pore size of about 10 to 12 microns. A representative material having these characteristics is POREX UF, which has an average molecular weight of about 3 million. This material is fully compatible with the FREONs and anhydrous ammonia and allows for the use of these very efficient working fluids in capillary loops.

  8. Computational study of inlet injection for a Pre-Mixed, Shock-Induced Combustion (PM/SIC) engine

    NASA Technical Reports Server (NTRS)

    Gonzalez, D. E.

    1995-01-01

    A computational simulation of reacting 2-D and 3-D flowfields in a model inlet section of a Pre-Mixed, Shock-Induced Combustion (PM/SIC) engine concept was performed. LARCK, a multi-dimensional Navier-Stokes code with finite-rate kinetics chemistry developed at NASA LaRC by J.A. White, was adapted for this simulation. The flow conditions in the simulation match those envisioned for the PM/SIC engine experiments currently planned at LaRC. The reacting flowfields were Mach 6.3 freestream air and Mach 2 hydrogen at various pressure and temperature conditions injected through a slot injector at the base of the inlet section. In the PM/SIC engine, fuel is injected at the inlet section upstream of the combustor, and reaction is initiated by the shock wave at the inlet which increases the gas temperature and pressure beyond the kinetic limits for reaction. Many challenges exist prior to establishing shock-controlled combustion as a practical engine concept. These challenges include fuel injection schemes that can provide proper fuel-air mixing without creating large losses in the inlet section, and control of the combustion process so that early ignition or combustion propagation through the inlet boundary layer does not occur. For this project, a parametrics study was carried out to model the fuel injection of hydrogen at different flow conditions. It was found that, as the fuel temperature and pressure were increased, the potential for pre-ignition was high at a short distance downstream of the slot injector. The next stage of this work will investigate injection techniques for enhancing mixing of fuel and air in a manner that prevents or reduces the potential for premature ignition observed numerically.

  9. Geomorphic Analysis of Mattituck Inlet and Goldsmith Inlet, Long Island, New York

    DTIC Science & Technology

    2005-07-01

    Militello et al. (2000). c. Site-specific inlet studies: Gofseyeff (1952), Czerniak (1977), Schmeltz et al. (1982), Militello and Kraus (2001), Kraus et al...New York, 11952-9500. Czerniak , M. T. (1977). "Ilet interaction and stability theory verification," Proceedings Coastal Sediments 󈨑, ASCE, 754-773

  10. Localization and imaging of gangliosides in mouse brain tissue sections by laserspray ionization inlet[S

    PubMed Central

    Richards, Alicia L.; Lietz, Christopher B.; Wager-Miller, James; Mackie, Ken; Trimpin, Sarah

    2012-01-01

    A new ionization method for the analysis of fragile gangliosides without undesired fragmentation or salt adduction is presented. In laserspray ionization inlet (LSII), the matrix/analyte sample is ablated at atmospheric pressure, and ionization takes place in the ion transfer capillary of the mass spectrometer inlet by a process that is independent of a laser wavelength or voltage. The softness of LSII allows the identification of gangliosides up to GQ1 with negligible sialic acid loss. This is of importance to the field of MS imaging, as undesired fragmentation has made it difficult to accurately map the spatial distribution of fragile ganglioside lipids in tissue. Proof-of-principle structural characterization of endogenous gangliosides using MSn fragmentation of multiply charged negative ions on a LTQ Velos and subsequent imaging of the GD1 ganglioside is demonstrated. This is the first report of multiply charged negative ions using inlet ionization. We find that GD1 is detected at higher levels in the mouse cortex and hippocampus compared with the thalamus. In LSII with the laser aligned in transmission geometry relative to the inlet, images were obtained in approximately 60 min using an inexpensive nitrogen laser. PMID:22262808

  11. Influence of Inlet / Shoal Complex on Adjacent Shorelines via Inlet Sink Method

    DTIC Science & Technology

    2012-07-01

    placing dredged material onto adjacent beaches in moderate quantities (~200-500K cu yd) since the 1970 ’s (Dredging Information System (DIS...southward to Matanzas Inlet. Analysis of the ebb shoal volume change between surveys was made within a GIS framework using an area mask (Fig. 6

  12. Effect of replacing surface inlets with blind or gravel inlets on sediment and phosphorus subsurface drainage losses.

    PubMed

    Feyereisen, Gary W; Francesconi, Wendy; Smith, Douglas R; Papiernik, Sharon K; Krueger, Erik S; Wente, Christopher D

    2015-03-01

    Open surface inlets that connect to subsurface tile drainage systems provide a direct pathway for movement of sediment, nutrients, and agrochemicals to surface waters. This study was conducted to determine the reduction in drainage effluent total suspended sediment (TSS) and phosphorus (P) concentrations and loads when open surface inlets were replaced with blind (in gravel capped with 30 cm of soil) or gravel (in very coarse sand/fine gravel) inlets. In Indiana, a pair of closed depressions in adjacent fields was fitted with open inlet tile risers and blind inlets in 2005 and monitored for flow and water chemistry. Paired comparisons on a storm event basis during the growing season for years 2006 to 2013 showed that TSS loads were 40.4 and 14.4 kg ha event for tile risers and blind inlets, respectively. Total P (TP) and soluble reactive P (SRP) loads were 66 and 50% less for the blind inlets, respectively. In Minnesota, TSS and SRP concentrations were monitored for 3 yr before and after modification of 24 open inlets to gravel inlets in an unreplicated large-field on-farm study. Median TSS concentrations were 97 and 8.3 mg L and median SRP concentrations were 0.099 and 0.064 mg L for the open inlet and gravel inlet periods, respectively. Median TSS and SRP concentrations were elevated for snowmelt vs. non-snowmelt seasons for open and gravel inlets. Both replacement designs reduced suspended sediment and P concentrations and loads. The Indiana study suggests blind inlets will be effective beyond a 10-yr service life.

  13. Method of making a small inlet optical panel

    DOEpatents

    Veligdan, James T.; Slobodin, David E.

    2004-02-03

    An optical panel having a small inlet, and a method of making a small inlet optical panel, are disclosed, which optical panel includes a individually coating, stacking, and cutting a first plurality of stacked optical waveguides to form an outlet face body with an outlet face, individually coating, stacking, and cutting a second plurality of stacked optical waveguides to form an inlet face body with an inlet face, and connecting an optical coupling element to the first plurality and second plurality of stacked optical waveguides, wherein the optical coupling element redirects light along a parallel axis of the inlet face to a parallel axis of the outlet face. In the preferred embodiment of the present invention, the inlet face is disposed obliquely with and askew from the outlet face.

  14. Zonal analysis of two high-speed inlets

    NASA Technical Reports Server (NTRS)

    Dilley, A. D.; Switzer, G. F.; Eppard, W. M.

    1991-01-01

    Using a zonal technique, thin layer Navier-Stokes solutions for two high speed inlet geometries are presented and compared with experimental data. The first configuration consists of a 3-D inlet preceded by a sharp flat plate. Results with two different grids demonstrate the importance of adequate grid refinement in high speed internal flow computations. The fine grid solution has reasonably good agreement with experimental heat transfer and pressure values inside the inlet. The other configuration consists of a 3-D inlet mounted on a research hypersonic forebody. Numerical results for this configuration have good agreement with experimental pressure data along the forebody, but not inside the inlet. A more refined grid calculation is currently being done to better predict the flowfield in the inlet.

  15. Boundary-layer-ingesting inlet flow control system

    NASA Technical Reports Server (NTRS)

    Owens, Lewis R. (Inventor); Allan, Brian G. (Inventor)

    2010-01-01

    A system for reducing distortion at the aerodynamic interface plane of a boundary-layer-ingesting inlet using a combination of active and passive flow control devices is disclosed. Active flow control jets and vortex generating vanes are used in combination to reduce distortion across a range of inlet operating conditions. Together, the vortex generating vanes can reduce most of the inlet distortion and the active flow control jets can be used at a significantly reduced control jet mass flow rate to make sure the inlet distortion stays low as the inlet mass flow rate varies. Overall inlet distortion, measured and described as average SAE circumferential distortion descriptor, was maintained at a value of 0.02 or less. Advantageous arrangements and orientations of the active flow control jets and the vortex generating vanes were developed using computational fluid dynamics simulations and wind tunnel experimentations.

  16. NASCRIN - NUMERICAL ANALYSIS OF SCRAMJET INLET

    NASA Technical Reports Server (NTRS)

    Kumar, A.

    1994-01-01

    The NASCRIN program was developed for analyzing two-dimensional flow fields in supersonic combustion ramjet (scramjet) inlets. NASCRIN solves the two-dimensional Euler or Navier-Stokes equations in conservative form by an unsplit, explicit, two-step finite-difference method. A more recent explicit-implicit, two-step scheme has also been incorporated in the code for viscous flow analysis. An algebraic, two-layer eddy-viscosity model is used for the turbulent flow calculations. NASCRIN can analyze both inviscid and viscous flows with no struts, one strut, or multiple struts embedded in the flow field. NASCRIN can be used in a quasi-three-dimensional sense for some scramjet inlets under certain simplifying assumptions. Although developed for supersonic internal flow, NASCRIN may be adapted to a variety of other flow problems. In particular, it should be readily adaptable to subsonic inflow with supersonic outflow, supersonic inflow with subsonic outflow, or fully subsonic flow. The NASCRIN program is available for batch execution on the CDC CYBER 203. The vectorized FORTRAN version was developed in 1983. NASCRIN has a central memory requirement of approximately 300K words for a grid size of about 3,000 points.

  17. Breathing zone air sampler

    DOEpatents

    Tobin, John

    1989-01-01

    A sampling apparatus is provided which comprises a sampler for sampling air in the breathing zone of a wearer of the apparatus and a support for the sampler preferably in the form of a pair of eyeglasses. The sampler comprises a sampling assembly supported on the frame of the eyeglasses and including a pair of sample transport tubes which are suspended, in use, centrally of the frame so as to be disposed on opposite sides of the nose of the wearer and which each include an inlet therein that, in use, is disposed adjacent to a respective nostril of the nose of the wearer. A filter holder connected to sample transport tubes supports a removable filter for filtering out particulate material in the air sampled by the apparatus. The sample apparatus is connected to a pump for drawing air into the apparatus through the tube inlets so that the air passes through the filter.

  18. Breathing zone air sampler

    SciTech Connect

    Tobin, J.

    1989-08-22

    A sampling apparatus is presented which comprises a sampler for sampling air in the breathing zone of a wearer of the apparatus and a support for the sampler preferably in the form of a pair of eyeglasses. The sampler comprises a sampling assembly supported on the frame of the eyeglasses and including a pair of sample transport tubes which are suspended, in use, centrally of the frame so as to be disposed on opposite sides of the nose of the wearer and which each include an inlet therein that, in use, is disposed adjacent to a respective nostril of the nose of the wearer. A filter holder connected to sample transport tubes supports a removable filter for filtering out particulate material in the air sampled by the apparatus. The sample apparatus is connected to a pump for drawing air into the apparatus through the tube inlets so that the air passes through the filter.

  19. Investigation on inlet recirculation characteristics of double suction centrifugal compressor with unsymmetrical inlet

    NASA Astrophysics Data System (ADS)

    Yang, Ce; Wang, Yingjun; Lao, Dazhong; Tong, Ding; Wei, Longyu; Liu, Yixiong

    2016-08-01

    The inlet recirculation characteristics of double suction centrifugal compressor with unsymmetrical inlet structures were studied in numerical method, mainly focused on three issues including the amounts and differences of the inlet recirculation in different working conditions, the circumferential non-uniform distributions of the inlet recirculation, the recirculation velocity distributions of the upstream slot of the rear impeller. The results show that there are some differences between the recirculation of the front impeller and that of the rear impeller in whole working conditions. In design speed, the recirculation flow rate of the rear impeller is larger than that of the front impeller in the large flow range, but in the small flow range, the recirculation flow rate of the rear impeller is smaller than that of the front impeller. In different working conditions, the recirculation velocity distributions of the front and rear impeller are non-uniform along the circumferential direction and their non-uniform extents are quite different. The circumferential non-uniform extent of the recirculation velocity varies with the working conditions change. The circumferential non-uniform extent of the recirculation velocity of front impeller and its distribution are determined by the static pressure distribution of the front impeller, but that of the rear impeller is decided by the coupling effects of the inlet flow distortion of the rear impeller, the circumferential unsymmetrical distribution of the upstream slot and the asymmetric structure of the volute. In the design flow and small flow conditions, the recirculation velocities at different circumferential positions of the mean line of the upstream slot cross-section of the rear impeller are quite different, and the recirculation velocities distribution forms at both sides of the mean line are different. The recirculation velocity distributions in the cross-section of the upstream slot depend on the static pressure

  20. Building a Copper Pipe "Xylophone."

    ERIC Educational Resources Information Center

    Lapp, David R.

    2003-01-01

    Explains how to use the equation for frequency of vibration of a transversely oscillating bar or pipe with both ends free to vibrate to build a simple and inexpensive xylophone from a 3-meter section of copper pipe. The instrument produces a full major scale and can be used to investigate various musical intervals. (Author/NB)

  1. Heat Pipe Thermal Conditioning Panel

    NASA Technical Reports Server (NTRS)

    Saaski, E. W.

    1973-01-01

    The development, fabrication, and evaluation of heat pipe thermal conditioning panels are discussed. The panels were designed and fabricated to be compatible with several planned NASA space vehicles, in terms of panel size, capacity, temperature gradients, and integration with various heat exchangers and electronic components. It was satisfactorily demonstrated that the heat pipe thermal conditioning panel meets the thermal efficiency and heat transport requirements.

  2. High temperature loop heat pipes

    SciTech Connect

    Anderson, W.G.; Bland, J.J.; Fershtater, Y.; Goncharov, K.A.; Nikitkin, M.; Juhasz, A.

    1995-12-31

    Advantages of loop heat pipes over conventional heat pipes include self-priming during start-up, improved tolerance for noncondensible gas, and ability for ground testing in any orientation. The applications for high temperature, alkali-metal working fluid loop heat pipes include space radiators, and bimodal systems. A high temperature loop heat pipe was fabricated and tested at 850 K, using cesium as the working fluid. Previous loop heat pipes were tested with ambient temperature working fluids at temperatures below about 450 K. The loop heat pipe had a titanium envelope, and a titanium aluminide wick. The maximum cesium loop heat pipe power was only about 600 watts, which was lower the predicted 1,000 W power. The power limitation may be due to a wettability problem with the cesium not completely wetting the titanium aluminide wick. This would reduce the pumping capability of the wick, and the maximum power that the heat pipe could carry. This problem could be solved by using a refractory metal powder wick, since the alkali metals are known to wet refractory metal wicks.

  3. Alternate high capacity heat pipe

    NASA Technical Reports Server (NTRS)

    Voss, F. E.

    1986-01-01

    The performance predictions for a fifty foot heat pipe (4 foot evaporator - 46 foot condensor) are discussed. These performance predictions are supported by experimental data for a four foot heat pipe. Both heat pipes have evaporators with axial groove wick structures and condensers with powder metal external artery wick structures. The predicted performance of a rectangular axial groove/external artery heat pipe operating in space is given. Heat transport versus groove width is plotted for 100, 200 and 300 grooves in the evaporator. The curves show that maximum power is achieved for groove widths from 0.040 to 0.053 as the number of grooves varies from 300 to 100. The corresponding range of maximum power is 3150 to 2400 watts. The relationships between groove width and heat pipe evaporate diameter for 100, 200 and 300 grooves in the evaporator are given. A four foot heat pipe having a three foot condenser and one foot evaporator was built and tested. The evaporator wick structure used axial grooves with rectangular cross sections, and the condenser wick structure used powder metal with an external artery configuration. Fabrication drawings are enclosed. The predicted and measured performance for this heat pipe is shown. The agreement between predicted and measured performance is good and therefore substantiates the predicted performance for a fifty foot heat pipe.

  4. Demonstrating Sound Impulses in Pipes.

    ERIC Educational Resources Information Center

    Raymer, M. G.; Micklavzina, Stan

    1995-01-01

    Describes a simple, direct method to demonstrate the effects of the boundary conditions on sound impulse reflections in pipes. A graphical display of the results can be made using a pipe, cork, small hammer, microphone, and fast recording electronics. Explains the principles involved. (LZ)

  5. Heat Pipe Blocks Return Flow

    NASA Technical Reports Server (NTRS)

    Eninger, J. E.

    1982-01-01

    Metal-foil reed valve in conventional slab-wick heat pipe limits heat flow to one direction only. With sink warmer than source, reed is forced closed and fluid returns to source side through annular transfer wick. When this occurs, wick slab on sink side of valve dries out and heat pipe ceases to conduct heat.

  6. Inlet Development for a Rocket Based Combined Cycle, Single Stage to Orbit Vehicle Using Computational Fluid Dynamics

    NASA Technical Reports Server (NTRS)

    DeBonis, J. R.; Trefny, C. J.; Steffen, C. J., Jr.

    1999-01-01

    Design and analysis of the inlet for a rocket based combined cycle engine is discussed. Computational fluid dynamics was used in both the design and subsequent analysis. Reynolds averaged Navier-Stokes simulations were performed using both perfect gas and real gas assumptions. An inlet design that operates over the required Mach number range from 0 to 12 was produced. Performance data for cycle analysis was post processed using a stream thrust averaging technique. A detailed performance database for cycle analysis is presented. The effect ot vehicle forebody compression on air capture is also examined.

  7. Experimental and numerical analyses of finned cross flow heat exchangers efficiency under non-uniform gas inlet flow conditions

    NASA Astrophysics Data System (ADS)

    Bury, Tomasz; Składzień, Jan; Widziewicz, Katarzyna

    2010-10-01

    The work deals with experimental and numerical thermodynamic analyses of cross-flow finned tube heat exchangers of the gas-liquid type. The aim of the work is to determine an impact of the gas non-uniform inlet on the heat exchangers performance. The measurements have been carried out on a special testing rig and own numerical code has been used for numerical simulations. Analysis of the experimental and numerical results has shown that the range of the non-uniform air inlet to the considered heat exchangers may be significant and it can significantly affect the heat exchanger efficiency.

  8. Power source for wireless sensors in pipes

    NASA Astrophysics Data System (ADS)

    Keddis, Sherif; Schwesinger, Norbert

    2016-04-01

    In this paper, we present investigations on wireless sensors for fluid control inside a pipe. Autarkic sensors are in the technical trend. They are typically connected with a transceiver unit for data transmission. Sensors usually need a lower amount of energy than data transceivers. Therefore, they are commonly supplied via wires or batteries with electricity. With common technologies, this request leads to high requirements on tightness in liquids since poor sealing could easily lead to failures. Replacement of batteries inside pipes is complicated and almost accompanied by a flow interruption. The application of energy harvesters as power supply is therefore a good alternative. In our studies we used flexible piezoelectric energy harvesters of PVDF (Poly-Vinylidene-Di-Fluoride). All harvesting units consist of piezoelectric PVDF-foils as active layers and Aluminum-foils as electrodes. The layers were stacked alternating on each other and wound to a spool. A LDPE-film wraps the spool and prevents the inflow of liquids. The device has following parameters:

  9. No. of windings: 4 in air, 4, 5, 7 in water
  10. Dimensions: 15 mm Ø 22mm
  11. Materials: PDVF: 25μm Aluminimum: 6μm, LDPE: 25μm
  12. A ring shaped bluff body was placed inside the pipe to induce turbulence in the fluid stream. As the harvesters have been arranged downstream of the bluff body, they were forced to oscillate independent of the media. In each case, deformation of the active layers led to a polarization and a separation of electrical charges. Experiments were carried out in a wind channel as well as in a water pipe. In air, the spool oscillates with a frequency of about 30Hz, at a wind speed of about 7m/s. A -Voltage of about 4V (peak-peak) was measured. This delivers in case of power adjustment, power values of about 0.54μW. In water, the velocity of the fluid was limited to nearly one tenth. Oscillation starts only at a water speed above 0.6m/s. The average oscillation

  13. Vapor spill pipe monitor

    DOEpatents

    Bianchini, G.M.; McRae, T.G.

    1983-06-23

    The invention is a method and apparatus for continually monitoring the composition of liquefied natural gas flowing from a spill pipe during a spill test by continually removing a sample of the LNG by means of a probe, gasifying the LNG in the probe, and sending the vaporized LNG to a remote ir gas detector for analysis. The probe comprises three spaced concentric tubes surrounded by a water jacket which communicates with a flow channel defined between the inner and middle, and middle and outer tubes. The inner tube is connected to a pump for providing suction, and the probe is positioned in the LNG flow below the spill pipe with the tip oriented partly downward so that LNG is continuously drawn into the inner tube through a small orifice. The probe is made of a high thermal conductivity metal. Hot water is flowed through the water jacket and through the flow channel between the three tubes to provide the necessary heat transfer to flash vaporize the LNG passing through the inner channel of the probe. The gasified LNG is transported through a connected hose or tubing extending from the probe to a remote ir sensor which measures the gas composition.

  14. Geothermal district piping - A primer

    SciTech Connect

    Rafferty, K.

    1989-11-01

    Transmission and distribution piping constitutes approximately 40 -60% of the capital costs of typical geothermal district heating systems. Selections of economical piping suitable for the fluid chemistry is critical. Presently, most piping (56%) in geothermal systems is of asbestos cement construction. Some fiberglass (19%) and steel (19%) is also in use. Identification of an economical material to replace asbestos cement is important to future project development. By providing information on relative costs, purchase considerations, existing material performance and new products, this report seeks to provide a background of information to the potential pipe purchaser. A brief discussion of the use of uninsulated piping in geothermal district heating systems is also provided. 5 refs., 19 figs., 1 tab.

  15. Flexible ultrasonic pipe inspection apparatus

    DOEpatents

    Jenkins, Charles F.; Howard, Boyd D.

    1998-01-01

    A flexible, modular ultrasonic pipe inspection apparatus, comprising a flexible, hollow shaft that carries a plurality of modules, including at least one rotatable ultrasonic transducer, a motor/gear unit, and a position/signal encoder. The modules are connected by flexible knuckle joints that allow each module of the apparatus to change its relative orientation with respect to a neighboring module, while the shaft protects electrical wiring from kinking or buckling while the apparatus moves around a tight corner. The apparatus is moved through a pipe by any suitable means, including a tether or drawstring attached to the nose or tail, differential hydraulic pressure, or a pipe pig. The rotational speed of the ultrasonic transducer and the forward velocity of the apparatus are coordinated so that the beam sweeps out the entire interior surface of the pipe, enabling the operator to accurately assess the condition of the pipe wall and determine whether or not leak-prone corrosion damage is present.

  16. Survey of inlet noise reduction concepts for gas turbine engines

    NASA Technical Reports Server (NTRS)

    Lansing, D. L.; Chestnutt, D.

    1976-01-01

    An overview is given of advanced concepts for the suppression of noise in the inlets of gas turbine engines. Inlet geometric and operating parameters are presented and design criteria for suppression methods are discussed. Noise suppression concepts are described, the directions of current research are reviewed. Problem areas requiring further work are indicated. Well established approaches to inlet noise reduction - namely, acoustic liners and high subsonic Mach number inlets which are the focus of considerable current research activity are considered along with the acoustic absorption and watet vapor injection.

  17. SUPIN: A Computational Tool for Supersonic Inlet Design

    NASA Technical Reports Server (NTRS)

    Slater, John W.

    2016-01-01

    A computational tool named SUPIN is being developed to design and analyze the aerodynamic performance of supersonic inlets. The inlet types available include the axisymmetric pitot, three-dimensional pitot, axisymmetric outward-turning, two-dimensional single-duct, two-dimensional bifurcated-duct, and streamline-traced inlets. The aerodynamic performance is characterized by the flow rates, total pressure recovery, and drag. The inlet flow-field is divided into parts to provide a framework for the geometry and aerodynamic modeling. Each part of the inlet is defined in terms of geometric factors. The low-fidelity aerodynamic analysis and design methods are based on analytic, empirical, and numerical methods which provide for quick design and analysis. SUPIN provides inlet geometry in the form of coordinates, surface angles, and cross-sectional areas. SUPIN can generate inlet surface grids and three-dimensional, structured volume grids for use with higher-fidelity computational fluid dynamics (CFD) analysis. Capabilities highlighted in this paper include the design and analysis of streamline-traced external-compression inlets, modeling of porous bleed, and the design and analysis of mixed-compression inlets. CFD analyses are used to verify the SUPIN results.

  18. CFD Models of a Serpentine Inlet, Fan, and Nozzle

    NASA Technical Reports Server (NTRS)

    Chima, R. V.; Arend, D. J.; Castner, R. S.; Slater, J. W.; Truax, P. P.

    2010-01-01

    Several computational fluid dynamics (CFD) codes were used to analyze the Versatile Integrated Inlet Propulsion Aerodynamics Rig (VIIPAR) located at NASA Glenn Research Center. The rig consists of a serpentine inlet, a rake assembly, inlet guide vanes, a 12-in. diameter tip-turbine driven fan stage, exit rakes or probes, and an exhaust nozzle with a translating centerbody. The analyses were done to develop computational capabilities for modeling inlet/fan interaction and to help interpret experimental data. Three-dimensional Reynolds averaged Navier-Stokes (RANS) calculations of the fan stage were used to predict the operating line of the stage, the effects of leakage from the turbine stream, and the effects of inlet guide vane (IGV) setting angle. Coupled axisymmetric calculations of a bellmouth, fan, and nozzle were used to develop techniques for coupling codes together and to investigate possible effects of the nozzle on the fan. RANS calculations of the serpentine inlet were coupled to Euler calculations of the fan to investigate the complete inlet/fan system. Computed wall static pressures along the inlet centerline agreed reasonably well with experimental data but computed total pressures at the aerodynamic interface plane (AIP) showed significant differences from the data. Inlet distortion was shown to reduce the fan corrected flow and pressure ratio, and was not completely eliminated by passage through the fan

  19. Blended Wing Body Systems Studies: Boundary Layer Ingestion Inlets With Active Flow Control

    NASA Technical Reports Server (NTRS)

    Geiselhart, Karl A. (Technical Monitor); Daggett, David L.; Kawai, Ron; Friedman, Doug

    2003-01-01

    A CFD analysis was performed on a Blended Wing Body (BWB) aircraft with advanced, turbofan engines analyzing various inlet configurations atop the aft end of the aircraft. The results are presented showing that the optimal design for best aircraft fuel efficiency would be a configuration with a partially buried engine, short offset diffuser using active flow control, and a D-shaped inlet duct that partially ingests the boundary layer air in flight. The CFD models showed that if active flow control technology can be satisfactorily developed, it might be able to control the inlet flow distortion to the engine fan face and reduce the powerplant performance losses to an acceptable level. The weight and surface area drag benefits of a partially submerged engine shows that it might offset the penalties of ingesting the low energy boundary layer air. The combined airplane performance of such a design might deliver approximately 5.5% better aircraft fuel efficiency over a conventionally designed, pod-mounted engine.

  20. Basic research in fan source noise: Inlet distortion and turbulence noise

    NASA Technical Reports Server (NTRS)

    Kantola, R. A.; Warren, R. E.

    1978-01-01

    A widely recognized problem in jet engine fan noise is the discrepancy between inflight and static tests. This discrepancy consists of blade passing frequency tones, caused by ingested turbulence that appear in the static tests but not in flight. To reduce the ingested distortions and turbulence in an anechoic chamber, a reverse cone inlet is used to guide the air into the fan. This inlet also has provisions for boundary layer suction and is used in conjunction with a turbulence control structure (TCS) to condition the air impinging on the fan. The program was very successful in reducing the ingested turbulence, to the point where reductions in the acoustic power at blade passing frequency are as high as 18 db for subsonic tip speeds. Even with this large subsonic tone suppression, the supersonic tip speed tonal content remains largely unchanged, indicating that the TCS did not appreciably attenuate the noise but effects the generation via turbulence reduction. Turbulence mapping of the inlet confirmed that the tone reductions are due to a reduction in turbulence, as the low frequency power spectra of the streamwise and transverse turbulence were reduced by up to ten times and 100 times, respectively.

  21. Inlet and airframe compatibility for a V/STOL fighter/attack aircraft with top-mounted inlets

    NASA Technical Reports Server (NTRS)

    Durston, D. A.; Smeltzer, D. B.

    1982-01-01

    Aerodynamic force and inlet-pressure data were obtained for 9.5% force and pressure models of a V/STOL fighter/attack aircraft configuration with top-mounted twin inlets. Data are presented from wind tunnel tests conducted at Mach numbers of 0.6, 0.9, and 1.2 at angles of attack up to 27-deg and angles of sideslip up to 12-deg. Trimmed aerodynamic characteristics and inlet performance were compared for three different leading-edge extension (LEX) configurations. The effects of wing leading- and trailing-edge flaps on the inlet were also determined. Maneuver performance was calculated from combined force and inlet-pressure data. The largest of the three LEX sizes tested gave the best airplane maneuver performance. Wing flap deflections improved inlet recovery at all Mach numbers.

  22. Inlet and airframe compatibility for a V/STOL fighter/attack aircraft with top-mounted inlets

    NASA Technical Reports Server (NTRS)

    Durston, D. A.; Smeltzer, D. B.

    1982-01-01

    Aerodynamic force and inlet pressure data are obtained for 9.5% force and pressure models of a V/STOL fighter/attack aircraft configuration with top mounted twin inlets. Data are presented from tests conducted in the Ames Unitary Wind Tunnels at Mach numbers of 0.6, 0.9, and 1.2 at angles of attack up to 27 deg. and angles of sideslip up to 12 deg. Trimmed aerodynamic characteristics and inlet performance are compared for three different leading edge extension (LEX) configurations. The effects of wing leading and trailing-edge flaps on the inlet are also determined. Maneuver perfromance is calculated form combined force and inlet pressure data. The largest of the three LEX sizes tested gives the best airplane maneuver performance. Wing flap deflections improved inlet recovery at all Mach numbers.

  23. Preliminary Results of the Determination of Inlet-Pressure Distortion Effects on Compressor Stall and Altitude Operating Limits of the J57-P-1 Turbojet Engine

    NASA Technical Reports Server (NTRS)

    Wallner, L. E.; Lubick, R. J.; Chelko, L. J.

    1955-01-01

    During an investigation of the J57-P-1 turbojet engine in the Lewis altitude wind tunnel, effects of inlet-flow distortion on engine stall characteristics and operating limits were determined. In addition to a uniform inlet-flow profile, the inlet-pressure distortions imposed included two radial, two circumferential, and one combined radial-circumferential profile. Data were obtained over a range of compressor speeds at an altitude of 50,000 and a flight Mach number of 0.8; in addition, the high- and low-speed engine operating limits were investigated up to the maximum operable altitude. The effect of changing the compressor bleed position on the stall and operating limits was determined for one of the inlet distortions. The circumferential distortions lowered the compressor stall pressure ratios; this resulted in less fuel-flow margin between steady-state operation and compressor stall. Consequently, the altitude operating Limits with circumferential distortions were reduced compared with the uniform inlet profile. Radial inlet-pressure distortions increased the pressure ratio required for compressor stall over that obtained with uniform inlet flow; this resulted in higher altitude operating limits. Likewise, the stall-limit fuel flows required with the radial inlet-pressure distortions were considerably higher than those obtained with the uniform inlet-pressure profile. A combined radial-circumferential inlet distortion had effects on the engine similar to the circumferential distortion. Bleeding air between the two compressors eliminated the low-speed stall limit and thus permitted higher altitude operation than was possible without compressor bleed.

  24. Modelling the mass migration phenomena in partially frozen heat pipes

    SciTech Connect

    Keddy, M.D.; Merrigan, M.A.; Critchley, E.

    1993-11-01

    Liquid metal heat pipes operated at power throughputs well below their design point and with sink temperatures below the freezing temperature of the working fluid may fail as a result of the working fluid migrating to a cold region within the pipe, freezing there, and not returning to the evaporator section. Eventually, sufficient working fluid inventory may be lost to the cold region to cause a local dry-out condition in the evaporator. A joint experimental and analytical effort by the Air Force Phillips Laboratory and Los Alamos National Laboratory is underway to investigate this phenomena. This paper presents an analytical model developed to describes this phenomena. The model provides for analytic determination of heat pipe temperature profiles, freeze-front locations and mass migration rates.