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Sample records for advanced design mixer

  1. Life-cycle cost analysis of advanced design mixer pump

    SciTech Connect

    Hall, M.N., Westinghouse Hanford

    1996-07-23

    This analysis provides cost justification for the Advanced Design Mixer Pump program based on the cost benefit to the Hanford Site of 4 mixer pump systems defined in terms of the life-cycle cost.A computer model is used to estimate the total number of service hours necessary for each mixer pump to operate over the 20-year retrieval sequence period for single-shell tank waste. This study also considered the double-shell tank waste retrieved prior to the single-shell tank waste which is considered the initial retrieval.

  2. Advanced Design Mixer Pump Tank 18 Design Modifications Summary Report

    SciTech Connect

    Adkins, B.J.

    2002-12-03

    The Westinghouse Savannah River Company (WSRC) is preparing to retrieve high level waste (HLW) from Tank 18 in early FY03 to provide feed for the Defense Waste Processing Facility (DWPF) and to support tank closure in FY04. As part of the Tank 18 project, WSRC will install a single Advanced Design Mixer Pump (ADMP) in the center riser of Tank 18 to mobilize, suspend, and mix radioactive sludge in preparation for transfer to Tank 7. The use of a single ADMP is a change to the current baseline of four (4) standard slurry pumps used during previous waste retrieval campaigns. The ADMP was originally conceived by Hanford and supported by SRS to provide a more reliable and maintainable mixer pump for use throughout the DOE complex. The ADMP underwent an extensive test program at SRS between 1998 and 2002 to assess reliability and hydraulic performance. The ADMP ran for approximately 4,200 hours over the four-year period. A detailed tear down and inspection of the pump following the 4,2 00-hour run revealed that the gas mechanical seals and anti-friction bearings would need to be refurbished/replaced prior to deployment in Tank 18. Design modifications were also needed to meet current Authorization Basis safety requirements. This report documents the modifications made to the ADMP in support of Tank 18 deployment. This report meets the requirements of Tanks Focus Area (TFA) Milestone 3591.4-1, ''Issue Report on Modifications Made to the ADMP,'' contained in Technical Task Plan (TTP) SR16WT51, ''WSRC Retrieval and Closure.''

  3. Recommendations for Advanced Design Mixer Pump Operation in Savannah River Site Tank 18F

    SciTech Connect

    Enderlin, Carl W.; Terrones, Guillermo; Bates, Cameron J.; Hatchell, Brian K.; Adkins, Brannen

    2003-10-30

    This report discusses technical issues and presents recommendations for operating the advanced design mixer pump (ADMP) in Tank 18 at the Savannah River Site (SRS). Also presented are the results obtained from simulated scaled pump-down tests carried out in the 1/4-scale double shell tank (DST) test facility at Pacific Northwest National Laboratory (PNNL). The work was conducted for the DOE Tanks Focus Area (TFA) by the Retrieval Process Development and Enhancement (RPD&E) program. The ability of the Tank 18 retrieval system to mobilize the solid waste and transport it through the retrieval pump, efficiently removing the solids from the tank, are evaluated.

  4. Lobed Mixer Optimization for Advanced Ejector Geometries

    NASA Technical Reports Server (NTRS)

    Waitz, Ian A.

    1996-01-01

    The overall objectives are: 1) to pursue analytical, computational, and experimental studies that enhance basic understanding of forced mixing phenomena relevant to supersonic jet noise reduction, and 2) to integrate this enhanced understanding (analytical, computational, and empirical) into a design-oriented model of a mixer-ejector noise suppression system. The work is focused on ejector geometries and flow conditions typical of those being investigated in the NASA High Speed Research Program (HSRP). The research will be carried out in collaboration with the NASA HSRP Nozzle Integrated Technology Development (ITD) Team, and will both contribute to, and benefit from, the results of other HSRP research. The noise suppressor system model that is being developed under this grant is distinct from analytical tools developed by industry because it directly links details of lobe geometry to mixer-ejector performance. In addition, the model provides a 'technology road map to define gaps in the current understanding of various phenomena related to mixer-ejector design and to help prioritize research areas. This report describes research completed in the past year, as well as work proposed for the following year.

  5. Forced mixer lobes in ejector designs

    NASA Technical Reports Server (NTRS)

    Presz, W. M., Jr.; Morin, B. L.; Gousy, R. G.

    1986-01-01

    Forced mixer lobes in augmentor primary ejectors obtain a 100-percent increase in pumping over conventional design, together with nearly complete mixing in very short mixing ducts, through the generation of large scale axial vorticity in the mixing duct. The vorticity causes rapid mixing of the primary and secondary flows with low losses; since mixing length is minimized, wall friction losses are reduced, allowing more secondary flow to be pumped for a given total pressure in the primary flow. Analytical results are presented that are judged to have significant implications for future ejector test work.

  6. Design and development of liquid hydrogen mixer unit

    NASA Technical Reports Server (NTRS)

    Morgan, R. W.; Wuertz, K.; Rudich, R. R.

    1973-01-01

    A dc brushless motor driven mixer unit (a vaneaxial fan) was designed and evaluated for use in cryogenic fluids (liquids and gases). It was found to operate well in all fluids in which it was tested. The test fluids were liquid and gaseous helium, hydrogen in the liquid phase gas phase and mixtures of the two phases, and liquid nitrogen. It operated for over 100 hr at cryogenic temperatures without damage to the bearings and at the conclusion of testing the condition of the bearings was such that an operational life of 5000 hr appeared possible. The unit demonstrated that (with the brushless dc motor principle) useful pumping of cryogenic fluids could be accomplished with very small power inputs to the mixer motor. During test, the motor input power varied from approximately 0.5 W to 2.5 W, depending on fluid density. The high power input produced a mixer efficiency of over 49 percent. In an earlier program (see NASA Report CR-72365), a mixer using an ac induction motor demonstrated an efficiency of 17.7 percent under the same conditions, illustrating the advantage of the dc brushless motor driven unit. The mixer also demonstrated its ability to automatically vary speed as a function of the density of the fluid being pumped. This causes the unit to deliver higher volumetric flow rates as fluid density decreases.

  7. Design of Balanced Mixers for ALMA Band-10

    NASA Astrophysics Data System (ADS)

    Shitov, Sergey V.; Koryukin, Oleg V.; Uzawa, Yoshinori; Noguchi, Takashi; Uvarov, Andrey V.; Bukovski, Maksim A.; Cohn, Ilya A.

    2007-06-01

    Two variants of balanced mixer employing twin-SIS structure are under development for 787-950 GHz frequency range. Easy-to-use Geometry Transformation method for modeling of superconducting microstrips is developed, compared to referenced methods and used for design of the mixers. Lens-antenna mixer is based on cross-slot antenna; it does not need any intervening optics between its lens and sub-reflector of ALMA telescope; simple yet efficient composition of lens-antenna cartridge is suggested. Compact single-chamber balanced waveguide mixer employs two SIS chips and capacitive probe for LO injection; coupling above -3 dB and signal loss below -20 dB are expected. Need in shifting of resonance frequency of twin-SIS mixer towards top of the frequency band is predicted using Tucker's theory in large-signal approximation. TRX considerably below 200 K (DSB) is simulated using high-quality hybrid SIS junction for NbTiN/Nb - AlOx - Nb/Al for Jc = 12 kA/cm2.

  8. A Multidisciplinary Approach to Mixer-Ejector Analysis and Design

    NASA Technical Reports Server (NTRS)

    Hendricks, Eric, S.; Seidel, Jonathan, A.

    2012-01-01

    The design of an engine for a civil supersonic aircraft presents a difficult multidisciplinary problem to propulsion system engineers. There are numerous competing requirements for the engine, such as to be efficient during cruise while yet quiet enough at takeoff to meet airport noise regulations. The use of mixer-ejector nozzles presents one possible solution to this challenge. However, designing a mixer-ejector which will successfully address both of these concerns is a difficult proposition. Presented in this paper is an integrated multidisciplinary approach to the analysis and design of these systems. A process that uses several low-fidelity tools to evaluate both the performance and acoustics of mixer-ejectors nozzles is described. This process is further expanded to include system-level modeling of engines and aircraft to determine the effects on mission performance and noise near airports. The overall process is developed in the OpenMDAO framework currently being developed by NASA. From the developed process, sample results are given for a notional mixer-ejector design, thereby demonstrating the capabilities of the method.

  9. A Matlab-Based Graphical User Interface for Simulation and Control Design of a Hydrogen Mixer

    NASA Technical Reports Server (NTRS)

    Richter, Hanz; Figueroa, Fernando

    2003-01-01

    A Graphical User Interface (GUI) that facilitates prediction and control design tasks for a propellant mixer is described. The Hydrogen mixer is used in rocket test stand operations at the NASA John C. Stennis Space Center. The mixer injects gaseous hydrogen (GH2) into a stream of liquid hydrogen (LH2) to obtain a combined flow with desired thermodynamic properties. The flows of GH2 and LH2 into the mixer are regulated by two control valves, and a third control valve is installed at the exit of the mixer to regulate the combined flow. The three valves may be simultaneously operated in order to achieve any desired combination of total flow, exit temperature and mixer pressure within the range of operation. The mixer, thus, constitutes a three-input, three-output system. A mathematical model of the mixer has been obtained and validated with experimental data. The GUI presented here uses the model to predict mixer response under diverse conditions.

  10. Design of a Broadband Millimeter-Wave Monolithic IQ Mixer

    NASA Astrophysics Data System (ADS)

    Xu, Leijun; Wang, Zhigong; Li, Qin

    2010-05-01

    A 26˜40 GHz millimeter-wave monolithic passive IQ mixer was designed by using Win’s 0.15-µm GaAs pHEMT process. It utilizes a ring diode structure, and the performance can be improved effectively by a modified Marchand balun and U-type coupled lines. Through on-wafer measurement, the mixer shows a conversion loss of 6.6˜9 dB over a bandwidth of 26˜40 GHz, an IF bandwidth from DC to 6 GHz, an image rejection ratio of 21˜30 dB, an LO-RF isolation of above 24 dB, an LO-IF isolation of above 35 dB, and an RF-IF isolation of above 25 dB.

  11. Design and performance of mass-produced sideband separating SIS mixers for ALMA band 4 receivers

    NASA Astrophysics Data System (ADS)

    Kojima, Takafumi; Kuroiwa, Koichi; Takahashi, Toshikazu; Fujii, Yumi; Uzawa, Yoshinori; Asayama, Shin'ichiro; Noguchi, Takashi

    2015-09-01

    We have designed and mass-produced low-noise sideband separating superconductor-insulator-superconductor (SIS) mixers for the Atacama Large Millimeter/submillimeter Array (ALMA) band 4 over the frequency range of 125-163 GHz. An integrated design was adopted for the band 4 sideband separating (2SB) mixer block because of the advantages it offers in terms of compactness, reduced testing time and lower cost. The mixer chip was designed to be robust for handling errors to avoid performance degradation caused by generation of the higher order mode in the mixer chip slot. Detailed analyses revealed its robustness and ability to ensure mass production of the 2SB mixers. Using the robust mixer design in addition to well-established waveguide technologies, all of the 2SB mixers met ALMA specifications for noise temperature and image rejection ratio.

  12. Design of a mixer for the thrust-vectoring system on the high-alpha research vehicle

    NASA Technical Reports Server (NTRS)

    Pahle, Joseph W.; Bundick, W. Thomas; Yeager, Jessie C.; Beissner, Fred L., Jr.

    1996-01-01

    One of the advanced control concepts being investigated on the High-Alpha Research Vehicle (HARV) is multi-axis thrust vectoring using an experimental thrust-vectoring (TV) system consisting of three hydraulically actuated vanes per engine. A mixer is used to translate the pitch-, roll-, and yaw-TV commands into the appropriate TV-vane commands for distribution to the vane actuators. A computer-aided optimization process was developed to perform the inversion of the thrust-vectoring effectiveness data for use by the mixer in performing this command translation. Using this process a new mixer was designed for the HARV and evaluated in simulation and flight. An important element of the Mixer is the priority logic, which determines priority among the pitch-, roll-, and yaw-TV commands.

  13. Quasi-optical antenna-mixer-array design for terahertz frequencies

    NASA Technical Reports Server (NTRS)

    Guo, Yong; Potter, Kent A.; Rutledge, David B.

    1992-01-01

    A new quasi-optical antenna-mixer-array design for terahertz frequencies is presented. In the design, antenna and mixer are combined into an entity, based on the technology in which millimeter-wave horn antenna arrays have been fabricated in silicon wafers. It consists of a set of forward- and backward-looking horns made with a set of silicon wafers. The front side is used to receive incoming signal, and the back side is used to feed local oscillator signal. Intermediate frequency is led out from the side of the array. Signal received by the horn array is picked up by antenna probes suspended on thin silicon-oxynitride membranes inside the horns. Mixer diodes will be located on the membranes inside the horns. Modeling of such an antenna-mixer-array design is done on a scaled model at microwave frequencies. The impedance matching, RF and LO isolation, and patterns of the array have been tested and analyzed.

  14. QCGAT mixer compound exhaust system design and static big model test report

    NASA Technical Reports Server (NTRS)

    Blackmore, W. L.; Thompson, C. E.

    1978-01-01

    A mixer exhaust system was designed to meet the proposed performance and exhaust jet noise goals for the AiResearch QCGAT engine. Some 0.35 scale models of the various nozzles were fabricated and aerodynamically and acoustically tested. Preliminary optimization, engine cycle matching, model test data and analysis are presented. A final mixer exhaust system is selected for optimum performance for the overall flight regime.

  15. Three-Wing Optical Mixer Design, Fabrication and Application to a μ-TAS

    NASA Astrophysics Data System (ADS)

    Ukita, Hiroo; Takada, Kosaku; Akagi, Daisuke; Ohnishi, Takakazu; Nonohara, Yasunari

    Optically driven 3-wing mixers are designed, fabricated and applied to liquid mixing in a microchannel. Three-wing mixers are easily fabricated into the desired shape by photolithography based on a large wing angle, and they are stable against trapping and rotation. Two-liquid mixing is visualized by the variation in milk fat colloid density, and velocity vectors are obtained through a stable and fast rotation rate of 500 rpm, even in a flow of 67 μm/s.

  16. Design of a TF34 turbofan mixer for reduction of flap impingement noise

    NASA Technical Reports Server (NTRS)

    Chamay, A.; Edkins, D. P.; Mishler, R. B.; Clapper, W. S.

    1972-01-01

    This portion of the TF-34 turbofan quiet engine studies has been devoted to the selection and design of a special mixer exhaust nozzle system to reduce the maximum 150 m (500 foot) sideline noise generated by the impingement of four engine exhausts on a STOL wing flap system to less than 92 PNdB. The design concept selected consists of a 12-lobe internal mixer and a 12-lobe external mixer mounted in series. The internal mixer reduces maximum exhaust velocities by mixing the fan and turbine streams. The external mixer is designed to reduce the velocity of the exhaust stream striking the wing flap surfaces. A ground test version of this concept has been designed to be installed and tested on an acoustically treated TF-34 engine nacelle, with flexibility to simulate a flight version of this concept which has also been defined. Estimated noise levels are 2 PNdB below the objective at approach and 2 PNdB above the objective at takeoff, with an uncertainty band of +3, -2 PNdB.

  17. Design of turbulent tangential micro-mixers that mix liquids on the nanosecond time scale.

    PubMed

    Mitic, Sandra; van Nieuwkasteele, Jan W; van den Berg, Albert; de Vries, Simon

    2015-01-15

    Unravelling (bio)chemical reaction mechanisms and macromolecular folding pathways on the (sub)microsecond time scale is limited by the time resolution of kinetic instruments for mixing reactants and observation of the progress of the reaction. To improve the mixing time resolution, turbulent four- and two-jet tangential micro-mixers were designed and characterized for their mixing and (unwanted) premixing performances employing acid-base reactions monitored by a pH-sensitive fluorescent dye. The mixing performances of the micro-mixers were determined after the mixing chamber in a free-flowing jet. The premixing behavior in the vortex chamber was assessed in an optically transparent glass-silicon replica of a previously well-characterized stainless-steel four-jet tangential micro-mixer. At the highest flow rates, complete mixing was achieved in 160ns with only approximately 9% premixing of the reactants. The mixing time of 160ns is at least 50 times shorter than estimated for other fast mixing devices. Key aspects to the design of ultrafast turbulent micro-mixers are discussed. The integration of these micro-mixers with an optical flow cell would enable the study of the very onset of chemical reactions in general and of enzyme catalytic reactions in particular. PMID:25447461

  18. Packaging design criteria, transfer and disposal of 102-AP mixer pump

    SciTech Connect

    Carlstrom, R.F.

    1994-11-23

    A mixer pump installed in storage tank 241-AP-102 (102-AP) has failed. This pump is referred to as the 102-AP mixer pump (APMP). The APMP will be removed from 102-AP 1 and a new pump will be installed. The main purpose of the Packaging Design Criteria (PDC) is to establish criteria necessary to design and fabricate a shipping container for the transfer and storage of the APMP from 102-AP. The PDC will be used as a guide to develop a Safety Evaluation for Packaging (SEP).

  19. Design and Evaluation of a Passive Alcove-based Microfluidic Mixer

    PubMed Central

    Egawa, Tsuyoshi; Durand, Jorge L.; Hayden, Eric; Rousseau, Denis L.; Yeh, Syun-Ru

    2012-01-01

    A novel passive microfluidic silicon mixer has been designed, optimized and fabricated. The architecture of the mixer consists of a simple “T” junction, made up by a 20 μm wide by 82 μm deep channel, followed by three repeats of an alcove, each with a triangular obstruction, arranged in a zigzag fashion. Numerical simulations were employed to optimize the geometry, particularly the dimensions of the alcoves, the relative orientation and the spacing between them, and the degree of intrusion associated with them. The simulation results demonstrate that chaotic flow due to recirculation within the alcoves results in transverse velocity that promotes effective fluid mixing. The microfluidic mixer with the simulation-optimized geometry was fabricated with photolithographic techniques and characterized by optical imaging, fluorescence and Raman microscope spectroscopy. At a sample flow rate of 20 μL/s, the mixer exhibits a short mixing deadtime of ~22 μs and a high mixing efficiency under both low and high viscosity conditions. The alcove-based microfluidic silicon mixer offers unique advantages for its short deadtime and slow sample consumption rate. In addition, it provides a valuable component for lab-on-a-chip applications for its ease of development into multiple networks for massively parallel analytical processes. PMID:19140669

  20. A compact design for the Josephson mixer: The lumped element circuit

    SciTech Connect

    Pillet, J.-D.; Flurin, E.; Mallet, F. Huard, B.

    2015-06-01

    We present a compact and efficient design in terms of gain, bandwidth, and dynamical range for the Josephson mixer, the superconducting circuit performing three-wave mixing at microwave frequencies. In an all lumped-element based circuit with galvanically coupled ports, we demonstrate nondegenerate amplification for microwave signals over a bandwidth up to 50 MHz for a power gain of 20 dB. The quantum efficiency of the mixer is shown to be about 70%, and its saturation power reaches −112 dBm.

  1. Structural design and analysis of a mixer pump for beyond-design- basis load

    SciTech Connect

    Rezvani, M.A.; Strehlow, J.P.; Baliga, R.; Kok, S.B.

    1994-03-01

    This paper presents the results of the structural evaluation of a mixer pump for a postulated drop accident. The mixer pump will be installed in a double-shell tank at the Hanford Site, near Richland, Washington. This tank has a 1,000,000-gallon (3,785,000 liter) capacity and is used to store radioactive waste before final disposal. The beyond-design-basis load case presented here is a postmulated drop of the pump during installation or removal. It is assumed that the pump assembly might be dropped approximateely 140 ft (15 m) from a height at which the bottom of the pump assembly is slightly above the top of the access riser to the bottom of the tank. The acceptance criterion for this load case is that the pump assembly shall not penetrate the primary tank liner. To ensure the integrity of the liner, the kinetic energy (developed in the pump drop) must be absorbed by some means to limit the impact force on the tank dome and thereby keep the pump from contacting the bottom of the tank. The limited clearance near the mounting assembly warranted an innovative two-step design of the energy absorbing system to limit the impact force on the tank dome to an acceptable value. This innovative design incorporates two energy absorbers in a unique series arrangement, one with the pump assembly and tile other in the pump pit.

  2. STME Hydrogen Mixer Study

    NASA Technical Reports Server (NTRS)

    Blumenthal, Rob; Kim, Dongmoon; Bache, George

    1992-01-01

    The hydrogen mixer for the Space Transportation Main Engine is used to mix cold hydrogen bypass flow with warm hydrogen coolant chamber gas, which is then fed to the injectors. It is very important to have a uniform fuel temperature at the injectors in order to minimize mixture ratio problems due to the fuel density variations. In addition, the fuel at the injector has certain total pressure requirements. In order to achieve these objectives, the hydrogen mixer must provide a thoroughly mixed fluid with a minimum pressure loss. The AEROVISC computational fluid dynamics (CFD) code was used to analyze the STME hydrogen mixer, and proved to be an effective tool in optimizing the mixer design. AEROVISC, which solves the Reynolds Stress-Averaged Navier-Stokes equations in primitive variable form, was used to assess the effectiveness of different mixer designs. Through a parametric study of mixer design variables, an optimal design was selected which minimized mixed fuel temperature variation and fuel mixer pressure loss. The use of CFD in the design process of the STME hydrogen mixer was effective in achieving an optimal mixer design while reducing the amount of hardware testing.

  3. Formal design review report project W-151 mixer pump procurement

    SciTech Connect

    Crass, D.W.

    1997-01-21

    A formal design review for WHC-S-0040 was held on January 21, 1993. The review was completed January 29, 1993. No outstanding action items existed. Comments were recorded on Record Comment Record (RCR) forms and incorporated into the specification. The specification was considered acceptable, approved and issued as WHC-S-0040, Rev. 0 on March 4, 1993.

  4. Low-noise room-temperature and cryogenic mixers for 80-120 GHz. [design for use on radio telescope

    NASA Technical Reports Server (NTRS)

    Kerr, A. R.

    1975-01-01

    A description is given of two new mixers designed to operate in the 80-120-GHz range on 36-ft radio telescope. It is shown that for a hard-driven diode the parasitic resistance and capacitance are the primary factors influencing the design of the diode mount. A room-temperature mixer is described which achieves a single-sideband (SSB) conversion loss (L) of 5.5 dB, and a SSB noise temperature (Tm) of 500 K (excluding the IF contribution) with a 1.4-GHz IF. A cryogenically cooled version, using a quartz structure to support the diode chip and contact whisker, achieves values of L = 5.8 dB and Tm = 300 K with a 4.75-GHz IF. The mixers use high-quality Schottky-barrier diodes in a one-quarter-height waveguide mount.

  5. Design of an exhaust mixer nozzle for the Avco-Lycoming Quiet Clean General Aviation Turbofan (QCGAT)

    NASA Technical Reports Server (NTRS)

    Hurley, J. F.; Anson, L.; Wilson, C.

    1978-01-01

    This report describes the design configuration and method used to design the forced engine exhaust to bypass air mixing system for Lycoming's QCGAT engine. This mixer is an integral part of the total engine and nacelle system and was configured to reduce the propulsion system noise and fuel consumption levels.

  6. New approach to the design of Schottky barrier diodes for THz mixers

    NASA Technical Reports Server (NTRS)

    Jelenski, A.; Grueb, A.; Krozer, V.; Hartnagel, H. L.

    1992-01-01

    Near-ideal GaAs Schottky barrier diodes especially designed for mixing applications in the THz frequency range are presented. A diode fabrication process for submicron diodes with near-ideal electrical and noise characteristics is described. This process is based on the electrolytic pulse etching of GaAs in combination with an in-situ platinum plating for the formation of the Schottky contacts. Schottky barrier diodes with a diameter of 1 micron fabricated by the process have already shown excellent results in a 650 GHz waveguide mixer at room temperature. A conversion loss of 7.5 dB and a mixer noise temperature of less than 2000 K have been obtained at an intermediate frequency of 4 GHz. The optimization of the diode structure and the technology was possible due to the development of a generalized Schottky barrier diode model which is valid also at high current densities. The common diode design and optimization is discussed on the basis of the classical theory. However, the conventional fomulas are valid only in a limited forward bias range corresponding to currents much smaller than the operating currents under submillimeter mixing conditions. The generalized new model takes into account not only the phenomena occurring at the junction such as current dependent recombination and drift/diffusion velocities, but also mobility and electron temperature variations in the undepleted epi-layer. Calculated diode I/V and noise characteristics are in excellent agreement with the measured values. Thus, the model offers the possibility of optimizing the diode structure and predicting the diode performance under mixing conditions at THz frequencies.

  7. High-speed Digital Baseband Mixer

    NASA Technical Reports Server (NTRS)

    Chan, F. P.; Quirk, M. P.; Jurgens, R. F.

    1985-01-01

    The feasibility of designing a digital, complex, baseband mixer with a 50 MHz sampling rate is explored. The baseband filter must provide passbands with linear phase response to minimize intersymbol interference. The effects of signal quantization, filter coefficient quantization, dynamic range, filter response characteristics, and the performance of the mixer when used for cross correlation and autocorrelation pulse detection techniques are discussed. This filter was designed for use in the high speed data acquisition system (HSDAS), an advanced experimental system in the Deep Space Network.

  8. Acoustic Characteristics of Various Treatment Panel Designs Specific to HSCT Mixer-Ejector Application

    NASA Technical Reports Server (NTRS)

    Salikuddin, M.; Kinzie, K.; Vu, D. D.; Langenbrunner, L. E.; Szczepkowski, G. T.

    2006-01-01

    The development process of liner design methodology is described in several reports. The results of the initial effort of concept development, screening, laboratory testing of various liner concepts, and preliminary correlation (generic data) are presented in a report Acoustic Characteristics of Various Treatment Panel Designs for HSCT Ejector Liner Acoustic Technology Development Program. The second phase of laboratory test results of more practical concepts and their data correlations are presented in this report (product specific). In particular, this report contains normal incidence impedance measurements of several liner types in both a static rig and in a high temperature flow duct rig. The flow duct rig allows for temperatures up to 400 F with a grazing flow up to Mach 0.8. Measurements of impedance, DC flow resistance, and in the flow rig cases, impact of the liner on boundary layer profiles are documented. In addition to liner rig tests, a limited number of tests were made on liners installed in a mixer-Ejector nozzle to confirm the performance of the liner prediction in an installed configuration.

  9. Energy Efficient Engine Exhaust Mixer Model Technology

    NASA Technical Reports Server (NTRS)

    Kozlowski, H.; Larkin, M.

    1981-01-01

    An exhaust mixer test program was conducted to define the technology required for the Energy Efficient Engine Program. The model configurations of 1/10 scale were tested in two phases. A parametric study of mixer design options, the impact of residual low pressure turbine swirl, and integration of the mixer with the structural pylon of the nacelle were investigated. The improvement of the mixer itself was also studied. Nozzle performance characteristics were obtained along with exit profiles and oil smear photographs. The sensitivity of nozzle performance to tailpipe length, lobe number, mixer penetration, and mixer modifications like scalloping and cutbacks were established. Residual turbine swirl was found detrimental to exhaust system performance and the low pressure turbine system for Energy Efficient Engine was designed so that no swirl would enter the mixer. The impact of mixer/plug gap was also established, along with importance of scalloping, cutbacks, hoods, and plug angles on high penetration mixers.

  10. SIS Mixer Design for a Broadband Millimeter Spectrometer Suitable for Rapid Line Surveys and Redshift Determinations

    NASA Technical Reports Server (NTRS)

    Rice, F.; Sumner, M.; Zmuidzinas, J.; Hu, R.; LeDuc, H.; Harris, A.; Miller, D.

    2004-01-01

    We present some detail of the waveguide probe and SIS mixer chip designs for a low-noise 180-300 GHz double- sideband receiver with an instantaneous RF bandwidth of 24 GHz. The receiver's single SIS junction is excited by a broadband, fixed-tuned waveguide probe on a silicon substrate. The IF output is coupled to a 6-18 GHz MMIC low- noise preamplifier. Following further amplification, the output is processed by an array of 4 GHz, 128-channel analog autocorrelation spectrometers (WASP 11). The single-sideband receiver noise temperature goal of 70 Kelvin will provide a prototype instrument capable of rapid line surveys and of relatively efficient carbon monoxide (CO) emission line searches of distant, dusty galaxies. The latter application's goal is to determine redshifts by measuring the frequencies of CO line emissions from the star-forming regions dominating the submillimeter brightness of these galaxies. Construction of the receiver has begun; lab testing should begin in the fall. Demonstration of the receiver on the Caltech Submillimeter Observatory (CSO) telescope should begin in spring 2003.

  11. Lobed Mixer Design for Noise Suppression Acoustic and Aerodynamic Test Data Analysis

    NASA Technical Reports Server (NTRS)

    Mengle, Vinod G.; Dalton, William N.; Boyd, Kathleen (Technical Monitor); Bridges, James (Technical Monitor)

    2002-01-01

    A comprehensive database for the acoustic and aerodynamic characteristics of several model-scale lobe mixers of bypass ratio 5 to 6 has been created for mixed jet speeds up to 1080 ft/s at typical take-off (TO) conditions of small-to-medium turbofan engines. The flight effect was simulated for Mach numbers up to 0.3. The static thrust performance and plume data were also obtained at typical TO and cruise conditions. The tests were done at NASA Lewis anechoic dome and ASK's FluiDyne Laboratories. The effect of several lobe mixer and nozzle parameters, such as, lobe scalloping, lobe count, lobe penetration and nozzle length was examined in terms of flyover noise at constant altitude. Sound in the nozzle reference frame was analyzed to understand the source characteristics. Several new concepts, mechanisms and methods are reported for such lobed mixers, such as, "boomerang" scallops, "tongue" mixer, detection of "excess" internal noise sources, and extrapolation of flyover noise data from one flight speed to different flight speeds. Noise reduction of as much as 3 EPNdB was found with a deeply scalloped mixer compared to annular nozzle at net thrust levels of 9500 lb for a 29 in. diameter nozzle after optimizing the nozzle length.

  12. Design and realization of a broadband single-side-band mixer with a very short settling time

    NASA Astrophysics Data System (ADS)

    Haßler, S.; Reichthalhammer, T.; Biebl, E.

    2010-10-01

    To achieve high range resolution in synthetic aperture radar imaging a frequency synthesizer with high bandwidth is a possible solution. To operate in the required frequency band an LF-signal usually has to be upconverted. In this paper we describe the design and realization of a broadband Single-Side-Band Mixer with a very short settling time between frequency steps of arbitrary length inside a high bandwidth. Compared to already existing SSB-Mixers, our novel concept has three major advantages: At first, the mixer could be used in combination with an arbitrary signal source. Due to a modular circuit concept it is possible to use the system for different input frequency ranges. Moreover, just by changing single modules, the output frequency-range can be adapted to individual requirements. Thirdly, as a main advantage, the system is able to generate a high frequency output span with a very fast settling time between frequency steps. Even with applied steps up to 400 MHz, the settling time remains below 3 μs, which is more than 5 times faster than the settling time of similar synthesizers.

  13. DESIGN OF 2.4 GHZ CMOS DIRECT CONVERSION LNA AND MIXER COMBINATION FOR WIRLESS DATA LINK TRANSCEIVER.

    SciTech Connect

    ZHAO, D.; OCONNOR, P.

    2002-04-10

    Three LNA and mixer combinations in 0.6{micro}m and 0.4{micro}m standard CMOS processes for direct-conversion receiver of 2.4GHz ISM band short-range wireless data-link applications are described in this paper. Taking low power dissipation as first consideration, these designs, employing differential common-source LNA and double balanced mixer architectures, achieve total conversion gain as high as 42.4dB, DSB noise figure as low as 9.5dB, output-referred IP3 as high as of 21.3dBm at about 4mA DC current consumption. This proves it is possible to apply standard CMOS process to implement receiver front-end with low power dissipation for this kind of application, but gain changeable LNA is needed to combat the dominant flicker noise of the mixer in order to achieve acceptable sensitivity and dynamic range at the same time.

  14. Demystifying Mixers

    ERIC Educational Resources Information Center

    Thompson, Douglas Earl

    2012-01-01

    Using music technology is a daily reality for music educators. The task may be as simple as readying a CD player for use in an elementary classroom or as complex as setting up a complete sound system--including microphones, mixer, amplifier, and speakers--for a live music production. One piece of music technology music educators constantly…

  15. Forward flight effects on mixer nozzle design and noise considerations for STOL externally blown flap systems.

    NASA Technical Reports Server (NTRS)

    Vonglahn, U. H.; Sekas, N.; Groesbeck, D. E.; Huff, R. G.

    1972-01-01

    Experimental data of the peak axial-velocity decay in a moving airstream are presented for several types of nozzles. The nozzles include a six-tube mixer nozzle of a type considered for reduction of jet-flap interaction noise for externally-blown-flap STOL aircraft. The effect of secondary flow on the core flow velocity decay of a bypass nozzle is also discussed. Tentative correlation equations are suggested for the configurations evaluated. Recommendations for minimizing forward velocity effects on velocity decay and jet-flap interaction noise are made.

  16. Forward flight effects on mixer nozzle design and noise considerations for STOL externally blown flap systems

    NASA Technical Reports Server (NTRS)

    Vonglahn, U. H.; Sekas, N.; Groesbeck, D. E.; Huff, R. G.

    1972-01-01

    Experimental data of the peak axial-velocity decay in a moving airstream are presented for several types of nozzles. The nozzles include a six-tube mixer nozzle of a type considered for reduction of jet-flap interaction noise for externally-blown-flap STOL aircraft. The effect of secondary flow on the core flow velocity decay of a bypass nozzle is also discussed. Tentative correlation equations are suggested for the configurations evaluated. Recommendations for minimizing forward velocity effects on velocity decay and jet-flap interaction noise are made.

  17. Forced Mixer Nozzle Optimization

    NASA Technical Reports Server (NTRS)

    Sheoran, Yogi; Hoover, Robert; Schuster, William; Anderson, Morris; Weir, Donald S.

    1999-01-01

    Computational fluid dynamic (CFD) and computational acoustic analyses (CAA) were performed for a TFE731-40 compound nozzle, a TFE731-60 mixer nozzle and an Energy Efficient Engine (E(sup 3)) mixer nozzle for comparison with available data. The CFD analyses were performed with a three dimensional, Navier-Stokes solution of the flowfield on an unstructured grid using the RAMPANT program. The CAA analyses were performed with the NASA Glenn MGB program using a structured grid. A successful aerodynamic solution for the TFE731-40 compound nozzle operating statically was obtained, simulating an engine operating on a test stand. Analysis of the CFD results of the TFE731-40 with the MGB program produced predicted sound power levels that agree quite well with the measured data front full-scale static engine tests. Comparison of the predicted sound pressure with the data show good agreement near the jet axis, but the noise levels are overpredicted at angles closer to the inlet. The predicted sound power level for the TFE731-60 did not agree as well with measured static engine data as the TFE731-40. Although a reduction in the predicted noise level due to the mixed flow was observed, the reduction was not as significant as the measured data. The analysis of the V2 mixer from the E(sup 3) study showed that peak temperatures predicted in the mixer exit flowfield were within 5 percent of the values measured by the exit probes. The noise predictions of the V2 mixer nozzle tended to be 3-5 dB higher in peak noise level than the measurements. In addition, the maximum frequency of the noise was also overpredicted. An analysis of the 3 candidate mixer nozzle configurations demonstrated the feasibility of using centerbody lobes and porosity to improve mixing efficiency. A final configuration was designed with a predicted thermal mixing efficiency that was 5 percent higher than the 3 candidate mixers. The results of the MGB noise calculations show that the final design will exceed the

  18. Lobed Mixer Design for Noise Suppression: Plume, Aerodynamic and Acoustic Data. Volume 2

    NASA Technical Reports Server (NTRS)

    Mengle, Vinod G.; Baker, V. David; Dalton, William N.; Bridges, James (Technical Monitor)

    2002-01-01

    A comprehensive database for the acoustic and aerodynamic characteristics of several model-scale lobe mixers of bypass ratio 5 to 6 has been created for mixed jet speeds up to 1080 ft per s at typical take-off (TO) conditions of small-to-medium turbofan engines. The flight effect was simulated for Mach numbers up to 0.3. The static thrust performance and plume data were also obtained at typical TO and cruise conditions. The tests were done at NASA Lewis anechoic dome and ASE's FluiDyne Laboratories. The effect of several lobe mixer and nozzle parameters, such as, lobe scalloping, lobe count, lobe penetration and nozzle length was examined in terms of flyover noise at constant altitude and also noise in the reference frame of the nozzle. This volume is divided into three parts: in the first two parts, we collate the plume survey data in graphical form (line, contour and surface plots) and analyze it; in part 3, we tabulate the aerodynamic data for the acoustics tests and the acoustic data in one-third octave band levels.

  19. BIB mixers

    NASA Technical Reports Server (NTRS)

    1995-01-01

    We have determined that the multi-pin 'microprocessor style' packages in which current Blocked Impurity Band (BIB) devices are mounted will not meet our IF bandwidth spec of greater than 2 GHz for a practical mixer. Hence we have started to repackage the Ga:Ge BIB devices in new microwave compatible packages. The smaller size of the microwave package mount necessitates cutting the BIB array down to include only the 3 smallest detectors: 0.2, 0.4, and 0.6 mm sq. A FIR beam incident at f/1.5 can be focussed on the smallest element for wavelengths shorter than 100 microns. A more typical (easier) beam convergence of f/3 will require 0.4 mm elements at 100 microns and 0.6 mm elements at 170 microns wavelength. Since the device capacitance (parasitic loss) scales with detector size, there is a tradeoff of speed of response and optical convenience. Our existing optics produce only the slower convergence beam, so we need to redesign the optical layout and are looking at long focal length all-reflective microscope objectives. BIB detectors and the edge-coupled microbolometers have restricted IF bandwidths, an order of magnitude less than what is possible with the Schottky-diode mixers we currently use for astronomical observations. Consequently the frequencies of the FIR laser lines must be close to the astronomical line of interest to be an effective Local Oscillator (LO). We have therefore begun a coordinated effort to discover and measure new FIR laser transition lines in close frequency coincidence with important astrophysical lines. Most of this effort involves pumping isotopic variants of known good laser molecules with laser lines from isotopic variants of CO2. We have been most successful in detecting new FIR lines in deuterated ammonia. One line in particular is very close to the frequency of HD rotational line at 2675 GHz.

  20. Advanced wind turbine design

    SciTech Connect

    Jamieson, P.M.; Jaffrey, A.

    1995-09-01

    Garrad Hassan have a project in progress funded by the UK Department of Trade and Industry (DTI) to assess the prospects and cost benefits of advanced wind turbine design. In the course of this work, a new concept, the coned rotor design, has been developed. This enables a wind turbine system to operate in effect with variable rotor diameter augmenting energy capture in light winds and shedding loads in storm conditions. Comparisons with conventional design suggest that a major benefit in reduced cost of wind generated electricity may be possible.

  1. MM wave quasioptical SIS mixers

    SciTech Connect

    Hu, Qing; Mears, C.A.; Richards, P.L.; Lloyd, F.L.

    1988-08-01

    We have tested the performance of planar SIS mixers with log-periodic antennas at near millimeter and submillimeter wave frequencies from 90 to 360 GHz. The large ..omega..R/sub N/C product (/approximately/10 at 90 GHz) of our Nb/NbO/sub x//Pb-In-Au junctions requires an integrated inductive tuning element to resonate the junction capacitance at the operating frequencies. We have used two types of integrated tuning element, which were designed with the aid of measurements using a Fourier transform spectrometer. Preliminary results indicate that the tuning elements can give very good mixer performance up to at least 200 GHz. An inductive wire in parallel with a 5-junction array gives a minimum mixer noise temperature of 115K (DSB) at 90 GHz with a FWHM bandwidth of 8 GHz. An open-ended microstrip stub in parallel with a single junction, gives minimum mixer noise temperatures of 150 and 200K (DSB) near 90 and 180 GHz with FWHM bandwidths of 4 and 3 GHz, respectively. The relatively high mixer noise temperatures compared to those of waveguide SIS mixers in a similar frequency range are attributed mainly to the losses in our optical system, which is being improved. 13 refs., 6 figs., 1 tab.

  2. Two- and three-dimensional modeling and optimization applied to the design of a fast hydrodynamic focusing microfluidic mixer for protein folding

    NASA Astrophysics Data System (ADS)

    Ivorra, Benjamin; Redondo, Juana L.; Santiago, Juan G.; Ortigosa, Pilar M.; Ramos, Angel M.

    2013-03-01

    We present a design of a microfluidic mixer based on hydrodynamic focusing which is used to initiate the folding process (i.e., changes of the molecular structure) of a protein. The folding process is initiated by diluting (from 90% to 30%) the local denaturant concentration (initially 6 M GdCl solution) in a short time interval we refer to as mixing time. Our objective is to optimize this mixer by choosing suitable shape and flow conditions in order to minimize this mixing time. To this end, we first introduce a numerical model that enables computation of the mixing time of a mixer. This model is based on a finite element method approximation of the incompressible Navier-Stokes equations coupled with the convective diffusion equation. To reduce the computational time, this model is implemented in both full three-dimensional (3D) and simplified two-dimensional (2D) versions; and we analyze the ability of the 2D model to approximate the mixing time predicted by the 3D model. We found that the 2D model approximates the mixing time predicted by the 3D model with a mean error of about 15%, which is considered reasonable. Then, we define a mixer optimization problem considering the 2D model and solve it using a hybrid global optimization algorithm. In particular, we consider geometrical variables and injection velocities as optimization parameters. We achieve a design with a predicted mixing time of 0.10 μs, approximately one order of magnitude faster than previous mixer designs. This improvement can be in part explained by the new mixer geometry including an angle of π/5 radians at the channel intersection and injections velocities of 5.2 m s-1 and 0.038 m s-1 for the side and central inlet channels, respectively. Finally, we verify the robustness of the optimized result by performing a sensitivity analysis of its parameters considering the 3D model. During this study, the optimized mixer was demonstrated to be robust by exhibiting mixing time variations of the same

  3. Microfluidic mixer designed for performing single-molecule kinetics with confocal detection on timescales from milliseconds to minutes.

    PubMed

    Wunderlich, Bengt; Nettels, Daniel; Benke, Stephan; Clark, Jennifer; Weidner, Sascha; Hofmann, Hagen; Pfeil, Shawn H; Schuler, Benjamin

    2013-08-01

    Microfluidic mixing in combination with single-molecule spectroscopy allows the investigation of complex biomolecular processes under non-equilibrium conditions. Here we present a protocol for building, installing and operating microfluidic mixing devices optimized for this purpose. The mixer is fabricated by replica molding with polydimethylsiloxane (PDMS), which allows the production of large numbers of devices at a low cost using a single microfabricated silicon mold. The design is based on hydrodynamic focusing combined with diffusive mixing and allows single-molecule kinetics to be recorded over five orders of magnitude in time, from 1 ms to ∼100 s. Owing to microfabricated particle filters incorporated in the inlet channels, the devices provide stable flow for many hours to days without channel blockage, which allows reliable collection of high-quality data. Modular design enables rapid exchange of samples and mixing devices, which are mounted in a specifically designed holder for use with a confocal microscopy detection system. Integrated Peltier elements provide temperature control from 4 to 37 °C. The protocol includes the fabrication of a silicon master, production of the microfluidic devices, instrumentation setup and data acquisition. Once a silicon master is available, devices can be produced and experiments started within ∼1 d of preparation. We demonstrate the performance of the system with single-molecule Förster resonance energy transfer (FRET) measurements of kinetics of protein folding and conformational changes. The dead time of 1 ms, as predicted from finite element calculations, was confirmed by the measurements. PMID:23845960

  4. Development of a Liner Design Methodology and Relevant Results of Acoustic Suppression in the Farfield for Mixer-Ejector Nozzles

    NASA Technical Reports Server (NTRS)

    Salikuddin, M.

    2006-01-01

    We have developed a process to predict noise field interior to the ejector and in the farfield for any liner design for a mixer-ejector of arbitrary scale factor. However, a number of assumptions, not verified for the current application, utilized in this process, introduce uncertainties in the final result, especially, on a quantitative basis. The normal impedance model for bulk with perforated facesheet is based on homogeneous foam materials of low resistivity. The impact of flow conditions for HSCT application as well as the impact of perforated facesheet on predicted impedance is not properly accounted. Based on the measured normal impedance for deeper bulk samples (i.e., 2.0 in.) the predicted reactance is much higher compared to the data at frequencies above 2 kHz for T-foam and 200 ppi SiC. The resistance is under predicted at lower frequencies (below 4 kHz) for these samples. Thus, the use of such predicted data in acoustic suppression is likely to introduce inaccuracies. It should be noted that the impedance prediction methods developed recently under liner technology program are not utilized in the studies described in this report due to the program closeout. Acoustic suppression prediction is based on the uniform flow and temperature conditions in a two-sided treated constant area rectangular duct. In addition, assumptions of equal energy per mode noise field and interaction of all frequencies with the treated surface for the entire ejector length may not be accurate. While, the use of acoustic transfer factor minimizes the inaccuracies associated with the prediction for a known test case, the assumption of the same factor for other liner designs and with different linear scale factor ejectors seems to be very optimistic. As illustrated in appendix D that the predicted noise suppression for LSM-1 is lower compared to the measured data is an indication of the above argument. However, the process seems to be more reliable when used for the same scale

  5. A Novel Split-Waveguide Mount Design For MM and SubMM wave frequency multipliers and Harmonic Mixers

    NASA Technical Reports Server (NTRS)

    Raisanen, Anti V.; Choudhury, Debabani; Dengler, Robert J.; Oswald, John E.; Siegel, Peter H.

    1993-01-01

    A novel split-waveguide mount for millimeter and submillimeter wave frequency multipliers and harmonic mixers is presented. It consists of only two pieces, block halves, which are mirror images of each other.

  6. Active microfluidic mixer chip

    NASA Astrophysics Data System (ADS)

    Niu, Xize; Liu, Liyu; Wen, Weijia; Sheng, Ping

    2006-04-01

    We report the design and fabrication of a chaotic mixer based on the electrorheological (ER) fluid-controlled valves. The flow in the main channel is perturbed by liquid flow in orthogonal side channels, driven by hydrodynamic pulsating pumps. Each pulsating pump consists of a chamber with diaphragm plus two out-of-phase ER valves operating in a push-pull mode. All the valves, pumps, and mixing channels are integrated in one polydimethylsioxane chip. Mixing characteristics in the main channel are controlled by the strength and frequency of external electric fields applied on the ER fluid.

  7. Advanced solar panel designs

    NASA Technical Reports Server (NTRS)

    Ralph, E. L.; Linder, E.

    1995-01-01

    This paper describes solar cell panel designs that utilize new hgih efficiency solar cells along with lightweight rigid panel technology. The resulting designs push the W/kg and W/sq m parameters to new high levels. These new designs are well suited to meet the demand for higher performance small satellites. This paper reports on progress made on two SBIR Phase 1 contracts. One panel design involved the use of large area (5.5 cm x 6.5 cm) GaAs/Ge solar cells of 19% efficiency combined with a lightweight rigid graphite fiber epoxy isogrid substrate configuration. A coupon (38 cm x 38 cm) was fabricated and tested which demonstrated an array specific power level of 60 W/kg with a potential of reaching 80 W/kg. The second panel design involved the use of newly developed high efficiency (22%) dual junction GaInP2/GaAs/Ge solar cells combined with an advanced lightweight rigid substrate using aluminum honeycomb core with high strength graphite fiber mesh facesheets. A coupon (38 cm x 38 cm) was fabricated and tested which demonstrated an array specific power of 105 W/kg and 230 W/sq m. This paper will address the construction details of the panels and an a analysis of the component weights. A strawman array design suitable for a typical small-sat mission is described for each of the two panel design technologies being studied. Benefits in respect to weight reduction, area reduction, and system cost reduction are analyzed and compared to conventional arrays.

  8. Advanced solar panel designs

    NASA Technical Reports Server (NTRS)

    Ralph, E. L.; Linder, E. B.

    1996-01-01

    Solar panel designs that utilize new high-efficiency solar cells and lightweight rigid panel technologies are described. The resulting designs increase the specific power (W/kg) achievable in the near-term and are well suited to meet the demands of higher performance small satellites (smallsats). Advanced solar panel designs have been developed and demonstrated on two NASA SBIR contracts at Applied Solar. The first used 19% efficient, large area (5.5 cm x 6.5 cm) GaAs/Ge solar cells with a lightweight rigid graphite epoxy isogrid substrate configuration. A 1,445 cm(exp 2) coupon was fabricated and tested to demonstrate 60 W/kg with a high potential of achieving 80 W/kg. The second panel design used new 22% efficiency, dual junction GaInP2/GaAs/Ge solar cells combined with a lightweight aluminum core/graphite fiber mesh facesheet substrate. A 1,445 cm(exp 2) coupon was fabricated and tested to demonstrate 105 W/kg with the potential of achieving 115 W/kg. This paper will address the construction details for the GaAs/isogrid and dual-junction GaAs/carbon mesh panel configurations. These are ultimately sized to provide 75 Watts and 119 Watts respectively for smallsats or may be used as modular building blocks for larger systems. GaAs/isogrid and dual-junction GaAs/carbon mesh coupons have been fabricated and tested to successfully demonstrate critical performance parameters and results are also provided here.

  9. Advanced turbocharger design study program

    NASA Technical Reports Server (NTRS)

    Culy, D. G.; Heldenbrand, R. W.; Richardson, N. R.

    1984-01-01

    The advanced Turbocharger Design Study consisted of: (1) the evaluation of three advanced engine designs to determine their turbocharging requirements, and of technologies applicable to advanced turbocharger designs; (2) trade-off studies to define a turbocharger conceptual design and select the engine with the most representative requirements for turbocharging; (3) the preparation of a turbocharger conceptual design for the Curtiss Wright RC2-32 engine selected in the trade-off studies; and (4) the assessment of market impact and the preparation of a technology demonstration plan for the advanced turbocharger.

  10. Terahertz radiation mixer

    DOEpatents

    Wanke, Michael C.; Allen, S. James; Lee, Mark

    2008-05-20

    A terahertz radiation mixer comprises a heterodyned field-effect transistor (FET) having a high electron mobility heterostructure that provides a gatable two-dimensional electron gas in the channel region of the FET. The mixer can operate in either a broadband pinch-off mode or a narrowband resonant plasmon mode by changing a grating gate bias of the FET. The mixer can beat an RF signal frequency against a local oscillator frequency to generate an intermediate frequency difference signal in the microwave region. The mixer can have a low local oscillator power requirement and a large intermediate frequency bandwidth. The terahertz radiation mixer is particularly useful for terahertz applications requiring high resolution.

  11. MEGARA cryostat advanced design

    NASA Astrophysics Data System (ADS)

    Ferrusca, D.; Castillo-Domínguez, Edgar; Velázquez, M.; Gil de Paz, A.; Carrasco, E.; Gallego, J.; Cedazo, R.; Iglesias-Páramo, J.

    2014-08-01

    MEGARA (Multi-Espectrógrafo en GTC de Alta Resolución para Astronomía) is an optical Integral-Field Unit and Multi-Object Spectrograph designed for the GTC (Gran Telescopio de Canarias) 10.4m telescope in La Palma. MEGARA project has already passed preliminary design review and the optics critical design review, first-light it is expected to take place at the end of 2016. MEGARA is a development under a GRANTECAN contract. In this paper we summarize the current status of the LN2 open-cycle cryostat which has been designed by the "Astronomical Instrumentation Lab for Millimeter Wavelengths" at the Instituto Nacional de Astrofísica, Óptica y Electrónica (INAOE) and emphasize the key parts of the system that have updated since the Preliminary Design, the main activities related to acceptance, integration, fabrication and maintenance plans which fit into the overall structure of the management plan of MEGARA are also described. The cryogenic work package of MEGARA has completed all the design stages and is ready for its Critical Design Review and then proceed to fabrication.

  12. Advanced hypersonic aircraft design

    NASA Technical Reports Server (NTRS)

    Utzinger, Rob; Blank, Hans-Joachim; Cox, Craig; Harvey, Greg; Mckee, Mike; Molnar, Dave; Nagy, Greg; Petersen, Steve

    1992-01-01

    The objective of this design project is to develop the hypersonic reconnaissance aircraft to replace the SR-71 and to complement existing intelligence gathering devices. The initial design considerations were to create a manned vehicle which could complete its mission with at least two airborne refuelings. The aircraft must travel between Mach 4 and Mach 7 at an altitude of 80,000 feet for a maximum range of 12,000 nautical miles. The vehicle should have an air breathing propulsion system at cruise. With a crew of two, the aircraft should be able to take off and land on a 10,000 foot runway, and the yearly operational costs were not to exceed $300 million. Finally, the aircraft should exhibit stealth characteristics, including a minimized radar cross-section (RCS) and a reduced sonic boom. The technology used in this vehicle should allow for production between the years 1993 and 1995.

  13. Advanced thrust chamber designs

    NASA Technical Reports Server (NTRS)

    Dietrich, F. J.; Leach, A. E.

    1971-01-01

    A regeneratively cooled thrust chamber has been designed and fabricated, consisting of an inner TD nickel liner which was spin formed, welded, and machined and an outer shell of electroformed nickel. Coolant channels were produced in the outer surface of the inner liner by the electric discharge machining process before electroforming the shell. Accessory manifolds and piping were attached by welding. Manufacturing processes employed are described.

  14. Thrust Augmentation with Mixer/Ejector Systems

    NASA Technical Reports Server (NTRS)

    Presz, Walter M., Jr.; Reynolds, Gary; Hunter, Craig

    2002-01-01

    Older commercial aircraft often exceed FAA (Federal Aviation Administration) sideline noise regulations. The major problem is the jet noise associated with the high exhaust velocities of the low bypass ratio engines on such aircraft. Mixer/ejector exhaust systems can provide a simple means of reducing the jet noise on these aircraft by mixing cool ambient air with the high velocity engine gases before they are exhausted to ambient. This paper presents new information on thrust performance predictions, and thrust augmentation capabilities of mixer/ejectors. Results are presented from the recent development program of the patented Alternating Lobe Mixer Ejector Concept (ALMEC) suppressor system for the Gulfstream GII, GIIB and GIII aircraft. Mixer/ejector performance procedures are presented which include classical control volume analyses, compound compressible flow theory, lobed nozzle loss correlations and state of the art computational fluid dynamic predictions. The mixer/ejector thrust predictions are compared to subscale wind tunnel test model data and actual aircraft flight test measurements. The results demonstrate that a properly designed mixer/ejector noise suppressor can increase effective engine bypass ratio and generate large thrust gains at takeoff conditions with little or no thrust loss at cruise conditions. The cruise performance obtained for such noise suppressor systems is shown to be a strong function of installation effects on the aircraft.

  15. Heat Balance Study for Submersible Mixer Pump

    SciTech Connect

    Lee, S.Y.

    2003-07-21

    A transient heat balance model was developed to assess the impact of a Submersible Mixer Pump (SMP) on waste temperature during the process of waste mixing and removal for the Type-I SRS tanks. The model results will be mainly used to determine the SMP design impacts on the waste tank temperature during operations and to develop a specification for a new SMP design to replace existing long-shaft mixer pumps used during waste removal. The model will also be used to provide input to the operation planning. This planning will be used as input to pump run duration in order to maintain temperature requirements within the tank during SMP operation.

  16. Optimization of SIS mixer elements

    NASA Technical Reports Server (NTRS)

    Mattauch, Robert J.

    1985-01-01

    Superconductor-Insulator-Superconductor (SIS) quantum mixers provide an approach to millimeter wave mixing - potentially offering conversion gain, a low local oscillator power demand, and potential mixer noise temperatures near the quantum limit. The development of a reliable fabrication technology for producing such high quality SIS devices for mixer applications in radio astronomy is the focus of the work.

  17. Advances in Ureteral Stent Design

    NASA Astrophysics Data System (ADS)

    Denstedt, John D.

    2007-04-01

    Ureteral stents are commonly used in urolithiasis patients for relief of obstruction or in association with stone treatments such as ureteroscopy and extracorporeal shock wave lithotripsy. There are currently many different bulk materials and coatings available for the manufacture of ureteral stents, however the ideal material has yet to be discovered. All potential biomaterials must undergo rigorous physical and biocompatibility testing before commercialization and use in humans. Despite significant advances in basic science research involving biocompatibility issues and biofilm formation, infection and encrustation remain associated with the use of biomaterials in the urinary tract. There have been many significant advances in the design of ureteral stents in recent years and these will be highlighted along with a discussion of future aspects of biomaterials and use of stents in association with urolithiasis.

  18. Advanced Aerospace Materials by Design

    NASA Technical Reports Server (NTRS)

    Srivastava, Deepak; Djomehri, Jahed; Wei, Chen-Yu

    2004-01-01

    The advances in the emerging field of nanophase thermal and structural composite materials; materials with embedded sensors and actuators for morphing structures; light-weight composite materials for energy and power storage; and large surface area materials for in-situ resource generation and waste recycling, are expected to :revolutionize the capabilities of virtually every system comprising of future robotic and :human moon and mars exploration missions. A high-performance multiscale simulation platform, including the computational capabilities and resources of Columbia - the new supercomputer, is being developed to discover, validate, and prototype next generation (of such advanced materials. This exhibit will describe the porting and scaling of multiscale 'physics based core computer simulation codes for discovering and designing carbon nanotube-polymer composite materials for light-weight load bearing structural and 'thermal protection applications.

  19. Intermediate/Advanced Research Design and Statistics

    NASA Technical Reports Server (NTRS)

    Ploutz-Snyder, Robert

    2009-01-01

    The purpose of this module is To provide Institutional Researchers (IRs) with an understanding of the principles of advanced research design and the intermediate/advanced statistical procedures consistent with such designs

  20. Planar doped barrier subharmonic mixers

    NASA Technical Reports Server (NTRS)

    Lee, T. H.; East, J. R.; Haddad, G. I.

    1992-01-01

    The Planar Doped Barrier (PDB) diode is a device consisting of a p(+) doping spike between two intrinsic layers and n(+) ohmic contacts. This device has the advantages of controllable barrier height, diode capacitance and forward to reverse current ratio. A symmetrically designed PDB has an anti-symmetric current vs. voltage characteristic and is ideal for use as millimeter wave subharmonic mixers. We have fabricated such devices with barrier heights of 0.3, 0.5 and 0.7 volts from GaAs and InGaAs using a multijunction honeycomb structure with junction diameters between one and ten microns. Initial RF measurements are encouraging. The 0.7 volt barrier height 4 micron GaAs devices were tested as subharmonic mixers at 202 GHz with an IF frequency of 1 GHz and had 18 dB of conversion loss. The estimated mismatch loss was 7 dB and was due to higher diode capacitance. The LO frequency was 100.5 GHz and the pump power was 8 mW.

  1. ADVANCES IN YUCCA MOUNTAIN DESIGN

    SciTech Connect

    Harrington, P.G.; Gardiner, J.T.; Russell, P.R.Z.; Lachman, K.D.; McDaniel, P.W.; Boutin, R.J.; Brown, N.R.; Trautner, L.J.

    2003-02-27

    Since site designation of the Yucca Mountain Project by the President, the U.S. Department of Energy (DOE) has begun the transition from the site characterization phase of the project to preparation of the license application. As part of this transition, an increased focus has been applied to the repository design. Several evolution studies were performed to evaluate the repository design and to determine if improvements in the design were possible considering advances in the technology for handling and packaging nuclear materials. The studies' main focus was to reduce and/or eliminate uncertainties in both the pre-closure and post-closure performance of the repository and to optimize operations. The scope and recommendations from these studies are the subjects of this paper and include the following topics: (1) a more phased approach for the surface facility that utilize handling and packaging of the commercial spent nuclear fuel in a dry environment rather than in pools as was presented in the site recommendation; (2) slight adjustment of the repository footprint and a phased approach for construction and emplacement of the repository subsurface; and (3) simplification of the construction, fabrication and installation of the waste package and drip shield.

  2. Slot antenna SIS mixers for submillimeter wavelengths

    NASA Technical Reports Server (NTRS)

    Zmuidzinas, Jonas; Leduc, Henry G.; Stern, J. A.

    1992-01-01

    We are developing improved versions of a slot antenna SIS mixer which we have previously described. The initial work demonstrated a double sideband noise temperature of 420 K for a 500 GHz quasi-optical SIS mixer employing a twin-slot antenna on a quartz dielectric substrate. A quartz hyperhemispherical lens is used to focus the incoming radiation onto the twin-slot antenna. The advantages of a twin-slot antenna include a low impedance (35 omega) and a clean, symmetric beam pattern into the dielectric with a 70 percent efficiency. In our original mixer, the radiation was coupled from the two slot antennas onto superconducting microstrip lines which fed the SIS junction. By performing an impedance transformation using tapered lines and by feeding the radiation from the two slots to the junction in parallel, the effective (real) impedance seen by the junction was reduced to just 4 omega. This very low impedance allowed a junction area of 2.3 sq micron to be used at 500 GHz, which was manufactured using optical lithography. However, no attempt was made to tune out the junction capacitance. We estimate that this capacitance reduces the impedance coupling efficiency to eta(sub Z) approx. equals 0.23, for our junction with omega R(sub N) C = 5.3 at 500 GHz. The recent development of techniques using electron-beam lithography to manufacture junctions with very small areas (approx. equals 0.1 sq microns) now allows considerably more flexibility in the design of SIS mixer circuits. We have redesigned the slot-antenna mixer to take advantage of this possibility. In particular, we have included a novel circuit which allows the junction capacitance to be tune out over a broad bandwidth. For instance, mixers designed for 800 GHz using NbN/MgO/NbN junctions with realistic parameters achieve a 3 dB impedance bandwidth of nearly 400 GHz. Furthermore, our circuit uses only short lengths of microstrip and should be less sensitive to RF losses than other designs. The improved

  3. Terahertz hot electron bolometer waveguide mixers for GREAT

    NASA Astrophysics Data System (ADS)

    Pütz, P.; Honingh, C. E.; Jacobs, K.; Justen, M.; Schultz, M.; Stutzki, J.

    2012-06-01

    Context. Supplementing the publications based on the first-light observations with the German REceiver for Astronomy at Terahertz frequencies (GREAT) on SOFIA, we present background information on the underlying heterodyne detector technology. This Letter complements the GREAT instrument Letter and focuses on the mixers itself. Aims: We describe the superconducting hot electron bolometer (HEB) detectors that are used as frequency mixers in the L1 (1400 GHz), L2 (1900 GHz), and M (2500 GHz) channels of GREAT. Measured performance of the detectors is presented and background information on their operation in GREAT is given. Methods: Our mixer units are waveguide-based and couple to free-space radiation via a feedhorn antenna. The HEB mixers are designed, fabricated, characterized, and flight-qualified in-house. We are able to use the full intermediate frequency bandwidth of the mixers using silicon-germanium multi-octave cryogenic low-noise amplifiers with very low input return loss. Results: Superconducting HEB mixers have proven to be practical and sensitive detectors for high-resolution THz frequency spectroscopy on SOFIA. We show that our niobium-titanium-nitride (NbTiN) material HEBs on silicon nitride (SiN) membrane substrates have an intermediate frequency (IF) noise roll-off frequency above 2.8 GHz, which does not limit the current receiver IF bandwidth. Our mixer technology development efforts culminate in the first successful operation of a waveguide-based HEB mixer at 2.5 THz and deployment for radioastronomy. A significant contribution to the success of GREAT is made by technological development, thorough characterization and performance optimization of the mixer and its IF interface for receiver operation on SOFIA. In particular, the development of an optimized mixer IF interface contributes to the low passband ripple and excellent stability, which GREAT demonstrated during its initial successful astronomical observation runs.

  4. Introduction of electrodehydrators with built-in jet mixers

    SciTech Connect

    Gershuni, S.S.; Baimbetov, A.M.; Idrisova, T.S.; Makhov, A.F.

    1985-09-01

    This paper describes an effective technique of crude oil desalting which is recirculation of water within the electrodehydrator by means of built-in jet mixers. Vertical electrodehydrators with built-in jet mixers have been tested and approved at the Novo-Ufa refinery. Design and operation of the vessel is described. Results from analyses of the oil during the test period are summarized. Retrofitting of electrodehydrators with built-in jet mixers proved increased capacity and the consumption of water and electric power in desalting was cut in half while oil loss in the electric desalting units was reduced substantially.

  5. Diffusion-Cooled Tantalum Hot-Electron Bolometer Mixers

    NASA Technical Reports Server (NTRS)

    Skalare, Anders; McGrath, William; Bumble, Bruce; LeDuc, Henry

    2004-01-01

    A batch of experimental diffusion-cooled hot-electron bolometers (HEBs), suitable for use as mixers having input frequencies in the terahertz range and output frequencies up to about a gigahertz, exploit the superconducting/normal-conducting transition in a thin strip of tantalum. The design and operation of these HEB mixers are based on mostly the same principles as those of a prior HEB mixer that exploited the superconducting/normal- conducting transition in a thin strip of niobium and that was described elsewhere.

  6. Modeling Tool Advances Rotorcraft Design

    NASA Technical Reports Server (NTRS)

    2007-01-01

    Continuum Dynamics Inc. (CDI), founded in 1979, specializes in advanced engineering services, including fluid dynamic modeling and analysis for aeronautics research. The company has completed a number of SBIR research projects with NASA, including early rotorcraft work done through Langley Research Center, but more recently, out of Ames Research Center. NASA Small Business Innovation Research (SBIR) grants on helicopter wake modeling resulted in the Comprehensive Hierarchical Aeromechanics Rotorcraft Model (CHARM), a tool for studying helicopter and tiltrotor unsteady free wake modeling, including distributed and integrated loads, and performance prediction. Application of the software code in a blade redesign program for Carson Helicopters, of Perkasie, Pennsylvania, increased the payload and cruise speeds of its S-61 helicopter. Follow-on development resulted in a $24 million revenue increase for Sikorsky Aircraft Corporation, of Stratford, Connecticut, as part of the company's rotor design efforts. Now under continuous development for more than 25 years, CHARM models the complete aerodynamics and dynamics of rotorcraft in general flight conditions. CHARM has been used to model a broad spectrum of rotorcraft attributes, including performance, blade loading, blade-vortex interaction noise, air flow fields, and hub loads. The highly accurate software is currently in use by all major rotorcraft manufacturers, NASA, the U.S. Army, and the U.S. Navy.

  7. Acoustic and Laser Doppler Anemometer Results for Confluent, 22-Lobed, and Unique-Lobed Mixer Exhaust Systems for Subsonic Jet Noise Reduction

    NASA Technical Reports Server (NTRS)

    Salikuddin, M.; Martens, S.; Shin, H.; Majjigi, R. K.; Krejsa, Gene (Technical Monitor)

    2002-01-01

    The objective of this task was to develop a design methodology and noise reduction concepts for high bypass exhaust systems which could be applied to both existing production and new advanced engine designs. Special emphasis was given to engine cycles with bypass ratios in the range of 4:1 to 7:1, where jet mixing noise was a primary noise source at full power takeoff conditions. The goal of this effort was to develop the design methodology for mixed-flow exhaust systems and other novel noise reduction concepts that would yield 3 EPNdB noise reduction relative to 1992 baseline technology. Two multi-lobed mixers, a 22-lobed axisymmetric and a 21-lobed with a unique lobe, were designed. These mixers along with a confluent mixer were tested with several fan nozzles of different lengths with and without acoustic treatment in GEAE's Cell 41 under the current subtask (Subtask C). In addition to the acoustic and LDA tests for the model mixer exhaust systems, a semi-empirical noise prediction method for mixer exhaust system is developed. Effort was also made to implement flowfield data for noise prediction by utilizing MGB code. In general, this study established an aero and acoustic diagnostic database to calibrate and refine current aero and acoustic prediction tools.

  8. Low Power Upconversion Mixer for Medical Remote Sensing

    PubMed Central

    Lioe, De Xing; Shafie, Suhaidi; Tan, Gim Heng

    2014-01-01

    This work presents the design of a low power upconversion mixer adapted in medical remote sensing such as wireless endoscopy application. The proposed upconversion mixer operates in ISM band of 433 MHz. With the carrier power of −5 dBm, the proposed mixer has an output inferred 1 dB compression point of −0.5 dBm with a corresponding output third-order intercept point (OIP3) of 7.1 dBm. The design of the upconversion mixer is realized on CMOS 0.13 μm platform, with a current consumption of 594 μA at supply voltage headroom of 1.2 V. PMID:25133266

  9. MICROFLUIDIC MIXERS FOR THE INVESTIGATION OF PROTEIN FOLDING USING SYNCHROTRON RADIATION CIRCULAR DICHROISM SPECTROSCOPY

    SciTech Connect

    Kane, A; Hertzog, D; Baumgartel, P; Lengefeld, J; Horsley, D; Schuler, B; Bakajin, O

    2006-03-20

    The purpose of this study is to design, fabricate and optimize microfluidic mixers to investigate the kinetics of protein secondary structure formation with Synchrotron Radiation Circular Dichroism (SRCD) spectroscopy. The mixers are designed to rapidly initiate protein folding reaction through the dilution of denaturant. The devices are fabricated out of fused silica, so that they are transparent in the UV. We present characterization of mixing in the fabricated devices, as well as the initial SRCD data on proteins inside the mixers.

  10. Embedding impedance approximations in the analysis of SIS mixers

    NASA Technical Reports Server (NTRS)

    Kerr, A. R.; Pan, S.-K.; Withington, S.

    1992-01-01

    Future millimeter-wave radio astronomy instruments will use arrays of many SIS receivers, either as focal plane arrays on individual radio telescopes, or as individual receivers on the many antennas of radio interferometers. Such applications will require broadband integrated mixers without mechanical tuners. To produce such mixers, it will be necessary to improve present mixer design techniques, most of which use the three-frequency approximation to Tucker's quantum mixer theory. This paper examines the adequacy of three approximations to Tucker's theory: (1) the usual three-frequency approximation which assumes a sinusoidal LO voltage at the junction, and a short-circuit at all frequencies above the upper sideband; (2) a five-frequency approximation which allows two LO voltage harmonics and five small-signal sidebands; and (3) a quasi five-frequency approximation in which five small-signal sidebands are allowed, but the LO voltage is assumed sinusoidal. These are compared with a full harmonic-Newton solution of Tucker's equations, including eight LO harmonics and their corresponding sidebands, for realistic SIS mixer circuits. It is shown that the accuracy of the three approximations depends strongly on the value of omega R(sub N)C for the SIS junctions used. For large omega R(sub N)C, all three approximations approach the eight-harmonic solution. For omega R(sub N)C values in the range 0.5 to 10, the range of most practical interest, the quasi five-frequency approximation is a considerable improvement over the three-frequency approximation, and should be suitable for much design work. For the realistic SIS mixers considered here, the five-frequency approximation gives results very close to those of the eight-harmonic solution. Use of these approximations, where appropriate, considerably reduces the computational effort needed to analyze an SIS mixer, and allows the design and optimization of mixers using a personal computer.

  11. Biasable Subharmonic Membrane Mixer for 520 to 600 GHz

    NASA Technical Reports Server (NTRS)

    Schlecht, Erich; Siegel, Peter; Mehdi, Imran; Gill, John; Velebir, James; Peralta, Alejandro; Tsang, Raymond; Oswald, John; Dengler, Robert

    2009-01-01

    The figure shows a biasable subharmonic mixer designed to operate in the frequency range from 520 to 600 GHz. This mixer is a prototype of low-power mixers needed for development of wideband, high-resolution spectrometers for measuring spectra of molecules in the atmospheres of Earth, other planets, and comets in the frequency range of 400 to 700 GHz. Three considerations dictated the main features of the design: It is highly desirable to operate the spectrometers at or slightly below room temperature. This consideration is addressed by choosing Schottky diodes as the frequency-mixing circuit elements because of all mixer diodes, Schottky diodes are the best candidates for affording sufficient sensitivity at or slightly below room-temperature range. The short wavelengths in the intended operating-frequency range translate to stringent requirements for precision of fabrication and assembly of the circuits; these requirements are even more stringent for wide-bandwidth circuits. This consideration is addressed in two ways: (1) As much as possible of the mixer circuitry is fabricated in the form of a monolithic integrated circuit on a GaAs membrane, employing a modified version of a process used previously to fabricate a non-subharmonic mixer for a frequency of 2.5 THz and frequency multipliers for frequencies up to 2 THz. (2) The remainder of the circuitry is precision machined into a waveguide block that holds the GaAs integrated circuit.

  12. Advanced Overfire Air system and design

    SciTech Connect

    Gene berkau

    2004-07-30

    The objective of the proposed project is to design, install and optimize a prototype advanced tangential OFA air system on two mass feed stoker boilers that can burn coal, biomass and a mixture of these fuels. The results will be used to develop a generalized methodology for retrofit designs and optimization of advanced OFA air systems. The advanced OFA system will reduce particulate and NOx emissions and improve overall efficiency by reducing carbon in the ash and excess oxygen. The advanced OFA will also provide capabilities for carrying full load and improved load following and transitional operations.

  13. Advanced absorber assembly design for breeder reactors

    SciTech Connect

    Pitner, A.L.; Birney, K.R.

    1980-01-01

    An advanced absorber assembly design has been developed for breeder reactor control rod applications that provides for improved in-reactor performance, longer lifetimes, and reduced fabrication costs. The design comprises 19 vented pins arranged in a circular array inside of round duct tubes. The absorber material is boron carbide; cladding and duct components are constructed from the modified Type 316 stainless steel alloy. Analyses indicate that this design will scram 30 to 40% faster than the reference FFTF absorber assembly. The basic design characteristics of this advanced FFTF absorber assembly are applicable to large core breeder reactor design concepts.

  14. Advanced Beamline Design for Fermilab's Advanced Superconducting Test Accelerator

    SciTech Connect

    Prokop, Christopher

    2014-01-01

    The Advanced Superconducting Test Accelerator (ASTA) at Fermilab is a new electron accelerator currently in the commissioning stage. In addition to testing superconducting accelerating cavities for future accelerators, it is foreseen to support a variety of Advanced Accelerator R&D (AARD) experiments. Producing the required electron bunches with the expected flexibility is challenging. The goal of this dissertation is to explore via numerical simulations new accelerator beamlines that can enable the advanced manipulation of electron bunches. The work especially includes the design of a low-energy bunch compressor and a study of transverse-to-longitudinal phase space exchangers.

  15. Advanced Design Studies. Final report

    SciTech Connect

    Steiner, Don

    2012-12-01

    The ARIES-CS project was a multi-year multi-institutional project to assess the feasibility of a compact stellarator as a fusion power plant. The work herein describes efforts to help design one aspect of the device, the divertor, which is responsible for the removal of particle and heat flux from the system, acting as the first point of contact between the magnetically confined hot plasma and the outside world. Specifically, its location and topology are explored, extending previous work on the sub ject. An optimized design is determined for the thermal particle flux using a suite of 3D stellarator design codes which trace magnetic field lines from just inside the confined plasma edge to their strike points on divertor plates. These divertor plates are specified with a newly developed plate design code. It is found that a satisfactory thermal design exists which maintains the plate temperature and heat load distribution below tolerable engineering limits. The design is unique, including a toroidal taper on the outboard plates which was found to be important to our results. The maximum thermal heat flux for the final design was 3.61 M W/m2 and the maximum peaking factor was 10.3, below prescribed limits of 10 M W/m2 and 15.6, respectively. The median length of field lines reaching the plates is about 250 m and their average angle of inclination to the surface is 2 deg. Finally, an analysis of the fast alphas, resulting from fusion in the core, which escape the plasma was performed. A method is developed for obtaining the mapping from magnetic coordinates to real-space coordinates for the ARIES-CS. This allows the alpha exit locations to be identified in real space for the first time. These were then traced using the field line algorithm as well as a guiding center routine accounting for their mass, charge, and specific direction and energy. Results show that the current design is inadequate for accommodating the alpha heat flux, capturing at most 1/3 of lost alphas

  16. Injector Design for Advanced Accelerators

    NASA Astrophysics Data System (ADS)

    Henestroza, Enrique; Faltens, A.

    1996-11-01

    Accelerator designs intended to provide acceleration at a much lower cost per Joule than the ILSE or ELISE designs are under study. For these designs, which typically have many beams, an injector of significantly lower cost is needed. A goal, which from our design appears to be achievable, is to reduce the transverse dimension to half that of the 2 MeV, 800 mA ILSE injector(E. Henestroza, ``Injectors for Heavy Ion Fusion", Proc. of the 11th International Wkshp. on Laser Interaction and Related Plasma Phenomena, 1993.) while generating about the same current. A single channel of a lower cost injector includes an 800 kV column, accelerating a 700 mA beam extracted from a potassium source of 4 cm radius by a 120 kV electrode. The beam passes into a superconducting 7 T solenoid of 15 cm aperture and 15 cm length. This high-field solenoid provides the focusing needed for a small beam without increasing the electric field gradient. The injector and its matching section, also designed, fit within a 12 cm radius, which is small enough to allow construction of attractive multi-beam injectors. We will present solutions for the generation and transport of 700 mA potassium beams of up to 1.6 MeV within the same transverse constraint.

  17. Design of an Advanced Expander Test Bed

    NASA Technical Reports Server (NTRS)

    Mitchell, John C.; Tabata, William K.

    1993-01-01

    The final design of the Advanced Expander Test Bed (AETB) is discussed. The AETB is a cryogenic rocket ground test unit being designed and built for NASA to enable validation of mission-focused technologies for advanced space engines. Based on the split expander cycle, it will operate at a nominal thrust of 20,000 lbf, a chamber pressure of 1200 psia, and may be operated off-design over a wide range of throttling conditions and mixture ratios. The design approach and configuration of the major components are described.

  18. Turbofan forced mixer lobe flow modeling. Part 3: Application to augment engines

    NASA Technical Reports Server (NTRS)

    Barber, T.; Moore, G. C.; Blatt, J. R.

    1988-01-01

    Military engines frequently need large quantities of thrust for short periods of time. The addition of an augmentor can provide such thrust increases but with a penalty of increased duct length and engine weight. The addition of a forced mixer to the augmentor improves performance and reduces the penalty, as well as providing a method for siting the required flame holders. In this report two augmentor concepts are investigated: a swirl-mixer augmentor and a mixer-flameholder augmentor. Several designs for each concept are included and an experimental assessment of one of the swirl-mixer augmentors is presented.

  19. Effect of Installation of Mixer/Ejector Nozzles on the Core Flow Exhaust of High-Bypass-Ratio Turbofan Engines

    NASA Technical Reports Server (NTRS)

    Harrington, Douglas E.

    1998-01-01

    The aerospace industry is currently investigating the effect of installing mixer/ejector nozzles on the core flow exhaust of high-bypass-ratio turbofan engines. This effort includes both full-scale engine tests at sea level conditions and subscale tests in static test facilities. Subscale model tests are to be conducted prior to full-scale testing. With this approach, model results can be analyzed and compared with analytical predications. Problem areas can then be identified and design changes made and verified in subscale prior to committing to any final design configurations for engine ground tests. One of the subscale model test programs for the integrated mixer/ejector development was a joint test conducted by the NASA Lewis Research Center and Pratt & Whitney Aircraft. This test was conducted to study various mixer/ejector nozzle configurations installed on the core flow exhaust of advanced, high-bypass-ratio turbofan engines for subsonic, commercial applications. The mixer/ejector concept involves the introduction of largescale, low-loss, streamwise vortices that entrain large amounts of secondary air and rapidly mix it with the primary stream. This results in increased ejector pumping relative to conventional ejectors and in more complete mixing within the ejector shroud. The latter improves thrust performance through the efficient energy exchange between the primary and secondary streams. This experimental program was completed in April 1997 in Lewis' CE-22 static test facility. Variables tested included the nozzle area ratio (A9/A8), which ranged from 1.6 to 3.0. This ratio was varied by increasing or decreasing the nozzle throat area, A8. Primary nozzles tested included both lobed mixers and conical primaries. These configurations were tested with and without an outer shroud, and the shroud position was varied by inserting spacers in it. In addition, data were acquired with and without secondary flow.

  20. Advanced space engine preliminary design

    NASA Technical Reports Server (NTRS)

    Cuffe, J. P. B.; Bradie, R. E.

    1973-01-01

    A preliminary design was completed for an O2/H2, 89 kN (20,000 lb) thrust staged combustion rocket engine that has a single-bell nozzle with an overall expansion ratio of 400:1. The engine has a best estimate vacuum specific impulse of 4623.8 N-s/kg (471.5 sec) at full thrust and mixture ratio = 6.0. The engine employs gear-driven, low pressure pumps to provide low NPSH capability while individual turbine-driven, high-speed main pumps provide the system pressures required for high-chamber pressure operation. The engine design dry weight for the fixed-nozzle configuration is 206.9 kg (456.3 lb). Engine overall length is 234 cm (92.1 in.). The extendible nozzle version has a stowed length of 141.5 cm (55.7 in.). Critical technology items in the development of the engine were defined. Development program plans and their costs for development, production, operation, and flight support of the ASE were established for minimum cost and minimum time programs.

  1. Static mixer improves desalting efficiency

    SciTech Connect

    Not Available

    1983-10-01

    An in-line static mixer has increased salt removal from crude oil at a large West Coast refinery, says the mixer supplier, Komax Systems Inc. The mixer was installed at a 150,000 b/d crude distillation unit's desalter. Crude at this refinery is a mixture of local production and imports from Indonesia and Alaska. In the past, the refiner used a typical globe-type mix valve to mix fresh water with crude at the desalters. The crude is heated to 300/sup 0/F., mixed with 5% fresh water, and then fed to the desalters. Chemical and electrostatic treatment is used in the desalters to remove salt and water from the crude.

  2. Advanced wing design survivability testing and results

    NASA Technical Reports Server (NTRS)

    Bruno, J.; Tobias, M.

    1992-01-01

    Composite wings on current operational aircraft are conservatively designed to account for stress/strain concentrations, and to assure specified damage tolerance. The technology that can lead to improved composite wing structures and associated structural efficiency is to increase design ultimate strain levels beyond their current limit of 3500 to 4000 micro-in/in to 6000 micro-in/in without sacrificing structural integrity, durability, damage tolerance, or survivability. Grumman, under the sponsorship of the Naval Air Development Center (NADC), has developed a high-strain composite wing design for a subsonic aircraft wing using novel and innovative design concepts and manufacturing methods, while maintaining a state-of-the-art fiber/resin system. The current advanced wing design effort addressed a tactical subsonic aircraft wing using previously developed, high-strain wing design concepts in conjunction with newer/emerging fiber and polymer matrix composite (PMC) materials to achieve the same goals, while reducing complexity. Two categories of advanced PMC materials were evaluated: toughened thermosets; and engineered thermoplastics. Advanced PMC materials offer the technological opportunity to take maximum advantage of improved material properties, physical characteristics, and tailorability to increase performance and survivability over current composite structure. Damage tolerance and survivability to various threats, in addition to structural integrity and durability, were key technical issues addressed during this study, and evaluated through test. This paper focuses on the live-fire testing, and the results performed to experimentally evaluate the survivability of the advanced wing design.

  3. Developments at the Advanced Design Technologies Testbed

    NASA Technical Reports Server (NTRS)

    VanDalsem, William R.; Livingston, Mary E.; Melton, John E.; Torres, Francisco J.; Stremel, Paul M.

    2003-01-01

    A report presents background and historical information, as of August 1998, on the Advanced Design Technologies Testbed (ADTT) at Ames Research Center. The ADTT is characterized as an activity initiated to facilitate improvements in aerospace design processes; provide a proving ground for product-development methods and computational software and hardware; develop bridging methods, software, and hardware that can facilitate integrated solutions to design problems; and disseminate lessons learned to the aerospace and information technology communities.

  4. A corner-reflector mixer mount for far infrared wavelengths.

    PubMed

    Zmuidzinas, J; Betz, A L; Boreiko, R T

    1989-01-01

    A new type of corner-reflector mixer mount, which has the advantages of ease of fabrication and assembly as well as frequency versatility, has been designed and constructed. The mixer works with arbitrary antenna lengths > or = 4 lambda with the reflector to antenna spacing adjusted to give a strong and symmetric central lobe. The predicted response patterns have been experimentally verified for various antenna lengths and operating frequencies between 800 and 2000 GHz. An important design feature is the incorporation of a microstrip matching network which eliminates IF impedance mismatch and provides mechanical isolation of the whisker antenna. PMID:11539754

  5. Mixer Assembly for a Gas Turbine Engine

    NASA Technical Reports Server (NTRS)

    Dai, Zhongtao (Inventor); Cohen, Jeffrey M. (Inventor); Fotache, Catalin G. (Inventor); Smith, Lance L. (Inventor); Hautman, Donald J. (Inventor)

    2015-01-01

    A mixer assembly for a gas turbine engine is provided, including a main mixer with fuel injection holes located between at least one radial swirler and at least one axial swirler, wherein the fuel injected into the main mixer is atomized and dispersed by the air flowing through the radial swirler and the axial swirler.

  6. Various advanced design projects promoting engineering education

    NASA Astrophysics Data System (ADS)

    The Universities Space Research Association (USRA) Advanced Design Program (ADP) program promotes engineering education in the field of design by presenting students with challenging design projects drawn from actual NASA interests. In doing so, the program yields two very positive results. Firstly, the students gain a valuable experience that will prepare them for design problems with which they will be faced in their professional careers. Secondly, NASA is able to use the work done by students as an additional resource in meeting its own design objectives. The 1994 projects include: Universal Test Facility; Automated Protein Crystal Growth Facility; Stiffening of the ACES Deployable Space Boom; Launch System Design for Access to Space; LH2 Fuel Tank Design for SSTO Vehicle; and Feed System Design for a Reduced Pressure Tank.

  7. Various advanced design projects promoting engineering education

    NASA Technical Reports Server (NTRS)

    1994-01-01

    The Universities Space Research Association (USRA) Advanced Design Program (ADP) program promotes engineering education in the field of design by presenting students with challenging design projects drawn from actual NASA interests. In doing so, the program yields two very positive results. Firstly, the students gain a valuable experience that will prepare them for design problems with which they will be faced in their professional careers. Secondly, NASA is able to use the work done by students as an additional resource in meeting its own design objectives. The 1994 projects include: Universal Test Facility; Automated Protein Crystal Growth Facility; Stiffening of the ACES Deployable Space Boom; Launch System Design for Access to Space; LH2 Fuel Tank Design for SSTO Vehicle; and Feed System Design for a Reduced Pressure Tank.

  8. Planar Submillimeter-Wave Mixer Technology with Integrated Antenna

    NASA Technical Reports Server (NTRS)

    Chattopadhyay, Gautam; Mehdi, Imran; Gill, John J.; Lee, Choonsup; lombart, Muria L.; Thomas, Betrand

    2010-01-01

    High-performance mixers at terahertz frequencies require good matching between the coupling circuits such as antennas and local oscillators and the diode embedding impedance. With the availability of amplifiers at submillimeter wavelengths and the need to have multi-pixel imagers and cameras, planar mixer architecture is required to have an integrated system. An integrated mixer with planar antenna provides a compact and optimized design at terahertz frequencies. Moreover, it leads to a planar architecture that enables efficient interconnect with submillimeter-wave amplifiers. In this architecture, a planar slot antenna is designed on a thin gallium arsenide (GaAs) membrane in such a way that the beam on either side of the membrane is symmetric and has good beam profile with high coupling efficiency. A coplanar waveguide (CPW) coupled Schottky diode mixer is designed and integrated with the antenna. In this architecture, the local oscillator (LO) is coupled through one side of the antenna and the RF from the other side, without requiring any beam sp litters or diplexers. The intermediate frequency (IF) comes out on a 50-ohm CPW line at the edge of the mixer chip, which can be wire-bonded to external circuits. This unique terahertz mixer has an integrated single planar antenna for coupling both the radio frequency (RF) input and LO injection without any diplexer or beamsplitters. The design utilizes novel planar slot antenna architecture on a 3- mthick GaAs membrane. This work is required to enable future multi-pixel terahertz receivers for astrophysics missions, and lightweight and compact receivers for planetary missions to the outer planets in our solar system. Also, this technology can be used in tera hertz radar imaging applications as well as for testing of quantum cascade lasers (QCLs).

  9. Simulator design for advanced ISDN satellite design and experiments

    NASA Technical Reports Server (NTRS)

    Pepin, Gerald R.

    1992-01-01

    This simulation design task completion report documents the simulation techniques associated with the network models of both the Interim Service ISDN (integrated services digital network) Satellite (ISIS) and the Full Service ISDN Satellite (FSIS) architectures. The ISIS network model design represents satellite systems like the Advanced Communication Technology Satellite (ACTS) orbiting switch. The FSIS architecture, the ultimate aim of this element of the Satellite Communications Applications Research (SCAR) program, moves all control and switching functions on-board the next generation ISDN communication satellite. The technical and operational parameters for the advanced ISDN communications satellite design will be obtained from the simulation of ISIS and FSIS engineering software models for their major subsystems. Discrete events simulation experiments will be performed with these models using various traffic scenarios, design parameters and operational procedures. The data from these simulations will be used to determine the engineering parameters for the advanced ISDN communications satellite.

  10. Liquid/Gas Flow Mixers

    NASA Technical Reports Server (NTRS)

    Fabris, Gracio

    1994-01-01

    Improved devices mix gases and liquids into bubbly or foamy flows. Generates flowing, homogeneous foams or homogeneous dispersions of small, noncoalescing bubbles entrained in flowing liquids. Mixers useful in liquid-metal magnetohydrodynamic electric-power generator, froth flotation in mining industry, wastewater treatment, aerobic digestion, and stripping hydrocarbon contaminants from ground water.

  11. Advanced Subsonic Airplane Design and Economic Studies

    NASA Technical Reports Server (NTRS)

    Liebeck, Robert H.; Andrastek, Donald A.; Chau, Johnny; Girvin, Raquel; Lyon, Roger; Rawdon, Blaine K.; Scott, Paul W.; Wright, Robert A.

    1995-01-01

    A study was made to examine the effect of advanced technology engines on the performance of subsonic airplanes and provide a vision of the potential which these advanced engines offered. The year 2005 was selected as the entry-into-service (EIS) date for engine/airframe combination. A set of four airplane classes (passenger and design range combinations) that were envisioned to span the needs for the 2005 EIS period were defined. The airframes for all classes were designed and sized using 2005 EIS advanced technology. Two airplanes were designed and sized for each class: one using current technology (1995) engines to provide a baseline, and one using advanced technology (2005) engines. The resulting engine/airframe combinations were compared and evaluated on the basis on sensitivity to basic engine performance parameters (e.g. SFC and engine weight) as well as DOC+I. The advanced technology engines provided significant reductions in fuel burn, weight, and wing area. Average values were as follows: reduction in fuel burn = 18%, reduction in wing area = 7%, and reduction in TOGW = 9%. Average DOC+I reduction was 3.5% using the pricing model based on payload-range index and 5% using the pricing model based on airframe weight. Noise and emissions were not considered.

  12. 50% Advanced Energy Design Guides: Preprint

    SciTech Connect

    Bonnema, E.; Leach, M.; Pless, S.; Liu, B.; Wang, W.; Thornton, B.; Williams, J.

    2012-07-01

    This paper presents the process, methodology, and assumptions for the development of the 50% Energy Savings Advanced Energy Design Guides (AEDGs), a design guidance document that provides specific recommendations for achieving 50% energy savings above the requirements of ANSI/ASHRAE/IESNA Standard 90.1-2004 in four building types: (1) Small to medium office buildings, (2) K-12 school buildings, (3) Medium to big box retail buildings, (4) Large hospital buildings.

  13. Advanced wind turbine design studies: Advanced conceptual study. Final report

    SciTech Connect

    Hughes, P; Sherwin, R

    1994-08-01

    In conjunction with the US Department of Energy and the National Renewable Energy Laboratory`s Advanced Wind Turbine Program, the Atlantic Orient Corporation developed preliminary designs for the next generation of wind turbines. These 50 kW and 350 kW turbines are based upon the concept of simplicity. By adhering to a design philosophy that emphasizes simplicity, we project that these turbines will produce energy at extremely competitive rates which will unlock the potential of wind energy domestically and internationally. The program consisted of three distinct phases. First, we evaluated the operational history of the Enertech 44 series wind turbines. As a result of this evaluation, we developed, in the second phase, a preliminary design for a new 50 kW turbine for the near-term market. In the third phase, we took a clean-sheet-of-paper approach to designing a 350 kW turbine focused on the mid-1990s utility market that incorporated past experience and advanced technology.

  14. Technical Workshop: Advanced Helicopter Cockpit Design

    NASA Technical Reports Server (NTRS)

    Hemingway, J. C. (Editor); Callas, G. P. (Editor)

    1984-01-01

    Information processing demands on both civilian and military aircrews have increased enormously as rotorcraft have come to be used for adverse weather, day/night, and remote area missions. Applied psychology, engineering, or operational research for future helicopter cockpit design criteria were identified. Three areas were addressed: (1) operational requirements, (2) advanced avionics, and (3) man-system integration.

  15. New engine and advanced component design

    SciTech Connect

    Not Available

    1990-01-01

    This book contains the proceedings on new engine and advance component design. Topics covered include: development of low emission high performance four valve engines, the effect of engine build options on powerplant inertias, silicon nitride turbocharger rotor for high performance automotive engines and development of Toyota reflex Burn (TRB) system in DI diesel.

  16. Advanced EVA system design requirements study

    NASA Technical Reports Server (NTRS)

    1986-01-01

    Design requirements and criteria for the Space Station Advanced Extravehicular Activity System (EVAS) including crew enclosures, portable life support systems, maneuvering propulsion systems, and related extravehicular activity (EVA) support equipment were defined and established. The EVA mission requirements, environments, and medical and physiological requirements, as well as opertional, procedures, and training issues were considered.

  17. An X-Band Mixer Engineered for 77 K Operation

    NASA Technical Reports Server (NTRS)

    Romanofsky, Robert R.

    1995-01-01

    An X-band Si-diode singly balanced mixer developed specifically for cryogenic operation is presented. In order to reduce thermal demands on a mechanical cooler, the mixer was designed to operate with a minimum of local oscillator (LO) power. That is, since the LO had to be cooled to reduce phase noise, it was desirable to minimize the LO drive. Novel embedding circuit strategy was responsible for nearly theoretical performance. The signal-matching circuit simultaneously provided a reactive termination to the image, sum, and first, second, and third LO harmonic frequencies. A conversion loss of 3.2 dB at 77 K with an LO drive of +1 dBm was measured. This loss included IF filter, dc block, and hybrid coupler losses. Mixer conversion loss is shown to be consistent with the theoretical performance limit expected from the intrinsic diode. The relationship among junction capacitance, flat-band potential, and conversion loss is examined.

  18. A 640 GHz Planar-Diode Fundamental Mixer/Receiver

    NASA Technical Reports Server (NTRS)

    Siegel, P.; Mehdi, I.; Dengler, R.; Lee, T.; Humphrey, D.; Pease, A.

    1998-01-01

    The design and performance of a 640 GHz solid-state receiver using a fundamental planar-Schottky-diode mixer, InP Gunn diode oscillator, whisker-contacted Schottky-varactor-diode sextupler and folded-Fabry-Perot diplexer are reported.

  19. Mirror Advanced Reactor Study interim design report

    SciTech Connect

    Not Available

    1983-04-01

    The status of the design of a tenth-of-a-kind commercial tandem-mirror fusion reactor is described at the midpoint of a two-year study. When completed, the design is to serve as a strategic goal for the mirror fusion program. The main objectives of the Mirror Advanced Reactor Study (MARS) are: (1) to design an attractive tandem-mirror fusion reactor producing electricity and synfuels (in alternate versions), (2) to identify key development and technology needs, and (3) to exploit the potential of fusion for safety, low activation, and simple disposal of radioactive waste. In the first year we have emphasized physics and engineering of the central cell and physics of the end cell. Design optimization and trade studies are continuing, and we expect additional modifications in the end cells to further improve the performance of the final design.

  20. Noise and loss in balanced and subharmonically pumped mixers. I - Theory. II - Application

    NASA Technical Reports Server (NTRS)

    Kerr, A. R.

    1979-01-01

    The theory of noise and frequency conversion for two-diode balanced and subharmonically pumped mixers is presented. The analysis is based on the equivalent circuit of the Schottky diode, having nonlinear capacitance, series resistance, and shot and thermal noise. Expressions for the conversion loss, noise temperature, and input and output impedances are determined in a form suitable for numerical analysis. In Part II, the application of the theory to practical mixers is demonstrated, and the properties of some two-diode mixers are examined. The subharmonically pumped mixer is found to be much more strongly affected by the loop inductance than the balanced mixer, and the ideal two-diode mixer using exponential diodes has a multiport noise-equivalent network (attenuator) similar to that of the ideal single-diode mixer. It is concluded that the theory can be extended to mixers with more than two diodes and will be useful for their design and analysis, provided a suitable nonlinear analysis is available to determine the diode waveforms.

  1. Design and demonstration of ultra-fast W-band photonic transmitter-mixer and detectors for 25 Gbits/sec error-free wireless linking.

    PubMed

    Chen, Nan-Wei; Shi, Jin-Wei; Tsai, Hsuan-Ju; Wun, Jhih-Min; Kuo, Fong-Ming; Hesler, Jeffery; Crowe, Thomas W; Bowers, John E

    2012-09-10

    A 25 Gbits/s error-free on-off-keying (OOK) wireless link between an ultra high-speed W-band photonic transmitter-mixer (PTM) and a fast W-band envelope detector is demonstrated. At the transmission end, the high-speed PTM is developed with an active near-ballistic uni-traveling carrier photodiode (NBUTC-PD) integrated with broadband front-end circuitry via the flip-chip bonding technique. Compared to our previous work, the wireless data rate is significantly increased through the improvement on the bandwidth of the front-end circuitry together with the reduction of the intermediate-frequency (IF) driving voltage of the active NBUTC-PD. The demonstrated PTM has a record-wide IF modulation (DC-25 GHz) and optical-to-electrical fractional bandwidths (68-128 GHz, ~67%). At the receiver end, the demodulation is realized with an ultra-fast W-band envelope detector built with a zero-bias Schottky barrier diode with a record wide video bandwidth (37 GHz) and excellent sensitivity. The demonstrated PTM is expected to find applications in multi-gigabit short-range wireless communication. PMID:23037246

  2. Frequency mixer having ferromagnetic film

    DOEpatents

    Khitun, Alexander; Roshchin, Igor V.; Galatsis, Kosmas; Bao, Mingqiang; Wang, Kang L.

    2016-03-29

    A frequency conversion device, which may include a radiofrequency (RF) mixer device, includes a substrate and a ferromagnetic film disposed over a surface of the substrate. An insulator is disposed over the ferromagnetic film and at least one microstrip antenna is disposed over the insulator. The ferromagnetic film provides a non-linear response to the frequency conversion device. The frequency conversion device may be used for signal mixing and amplification. The frequency conversion device may also be used in data encryption applications.

  3. Ganged series potentiometer mixer networks

    NASA Technical Reports Server (NTRS)

    Burhans, R. W.

    1974-01-01

    A ganged potentiometer with the interesting property of a constant 10k ohm or greater series impedance for all rotations of the shaft was rediscovered. The device provided a versatile passive mixer circuit when used with most signal sources and can be used as a variable series input summing resistor in operational amplifier networks. The potentiometer gave simple solutions to missing problems with a single control knob.

  4. Advanced Extravehicular Mobility Unit Informatics Software Design

    NASA Technical Reports Server (NTRS)

    Wright, Theodore

    2014-01-01

    This is a description of the software design for the 2013 edition of the Advanced Extravehicular Mobility Unit (AEMU) Informatics computer assembly. The Informatics system is an optional part of the space suit assembly. It adds a graphical interface for displaying suit status, timelines, procedures, and caution and warning information. In the future it will display maps with GPS position data, and video and still images captured by the astronaut.

  5. Advanced Solid Rocket Motor case design status

    NASA Technical Reports Server (NTRS)

    Palmer, G. L.; Cash, S. F.; Beck, J. P.

    1993-01-01

    The Advanced Solid Rocket Motor (ASRM) case design aimed at achieving a safer and more reliable solid rocket motor for the Space Shuttle system is considered. The ASRM case has a 150.0 inch diameter, three equal length segment, and 9Ni-4CO-0.3C steel alloy. The major design features include bolted casebolted case joints which close during pressurization, plasma arc welded factory joints, integral stiffener for splash down and recovery, and integral External Tank attachment rings. Each mechanical joint has redundant and verifiable o-ring seals.

  6. Advanced Solid Rocket Motor case design status

    NASA Astrophysics Data System (ADS)

    Palmer, G. L.; Cash, S. F.; Beck, J. P.

    1993-06-01

    The Advanced Solid Rocket Motor (ASRM) case design aimed at achieving a safer and more reliable solid rocket motor for the Space Shuttle system is considered. The ASRM case has a 150.0 inch diameter, three equal length segment, and 9Ni-4CO-0.3C steel alloy. The major design features include bolted casebolted case joints which close during pressurization, plasma arc welded factory joints, integral stiffener for splash down and recovery, and integral External Tank attachment rings. Each mechanical joint has redundant and verifiable o-ring seals.

  7. Advanced control design for hybrid turboelectric vehicle

    NASA Astrophysics Data System (ADS)

    Abban, Joseph; Norvell, Johnesta; Momoh, James A.

    1995-08-01

    The new environment standards are a challenge and opportunity for industry and government who manufacture and operate urban mass transient vehicles. A research investigation to provide control scheme for efficient power management of the vehicle is in progress. Different design requirements using functional analysis and trade studies of alternate power sources and controls have been performed. The design issues include portability, weight and emission/fuel efficiency of induction motor, permanent magnet and battery. A strategic design scheme to manage power requirements using advanced control systems is presented. It exploits fuzzy logic, technology and rule based decision support scheme. The benefits of our study will enhance the economic and technical feasibility of technological needs to provide low emission/fuel efficient urban mass transit bus. The design team includes undergraduate researchers in our department. Sample results using NASA HTEV simulation tool are presented.

  8. ESD protection design for advanced CMOS

    NASA Astrophysics Data System (ADS)

    Huang, Jin B.; Wang, Gewen

    2001-10-01

    ESD effects in integrated circuits have become a major concern as today's technologies shrink to sub-micron/deep- sub-micron dimensions. The thinner gate oxide and shallower junction depth used in the advanced technologies make them very vulnerable to ESD damages. The advanced techniques like silicidation and STI (shallow trench insulation) used for improving other device performances make ESD design even more challenging. For non-silicided technologies, a certain DCGS (drain contact to gate edge spacing) is needed to achieve ESD hardness for nMOS output drivers and nMOS protection transistors. The typical DCGS values are 4-5um and 2-3um for 0.5um and 0.25um CMOS, respectively. The silicidation reduces the ballast resistance provided by DCGS with at least a factor of 10. As a result, scaling of the ESD performance with device width is lost and even zero ESD performance is reported for standard silicided devices. The device level ESD design is focused in this paper, which includes GGNMOS (gate grounded NMOS) and GCNMOS (gate coupled NMOS). The device level ESD testing including TLP (transmission line pulse) is given. Several ESD issues caused by advanced technologies have been pointed out. The possible solutions have been developed and summarized including silicide blocking, process optimization, back-end ballasting, and new protection scheme, dummy gate/n-well resistor ballsting, etc. Some of them require process cost increase, and others provide novel, compact, and simple design but involving royalty/IP (intellectual property) issue. Circuit level ESD design and layout design considerations are covered. The top-level ESD protection strategies are also given.

  9. Variable mixer propulsion cycle

    NASA Technical Reports Server (NTRS)

    Rundell, D. J.; Mchugh, D. P.; Foster, T.; Brown, R. H. (Inventor)

    1978-01-01

    A design technique, method and apparatus are delineated for controlling the bypass gas stream pressure and varying the bypass ratio of a mixed flow gas turbine engine in order to achieve improved performance. The disclosed embodiments each include a mixing device for combining the core and bypass gas streams. The variable area mixing device permits the static pressures of the core and bypass streams to be balanced prior to mixing at widely varying bypass stream pressure levels. The mixed flow gas turbine engine therefore operates efficiently over a wide range of bypass ratios and the dynamic pressure of the bypass stream is maintained at a level which will keep the engine inlet airflow matched to an optimum design level throughout a wide range of engine thrust settings.

  10. Advanced turbine systems: Studies and conceptual design

    SciTech Connect

    van der Linden, S.; Gnaedig, G.; Kreitmeier, F.

    1993-11-01

    The ABB selection for the Advanced Turbine System (ATS) includes advanced developments especially in the hot gas path of the combustion turbine and new state-of-the-art units such as the steam turbine and the HRSG. The increase in efficiency by more than 10% multiplicative compared to current designs will be based on: (1) Turbine Inlet Temperature Increase; (2) New Cooling Techniques for Stationary and Rotating Parts; and New Materials. Present, projected component improvements that will be introduced with the above mentioned issues will yield improved CCSC turbine performance, which will drive the ATS selected gas-fired reference CC power plant to 6 % LHV or better. The decrease in emission levels requires a careful optimization of the cycle design, where cooling air consumption has to be minimized. All interfaces of the individual systems in the complete CC Plant need careful checks, especially to avoid unnecessary margins in the individual designs. This study is an important step pointing out the feasibility of the ATS program with realistic goals set by DOE, which, however, will present challenges for Phase II time schedule of 18 months. With the approach outlined in this study and close cooperation with DOE, ATS program success can be achieved to deliver low emissions and low cost of electricity by the year 2002. The ABB conceptual design and step approach will lead to early component demonstration which will help accelerate the overall program objectives.

  11. Advanced heat receiver conceptual design study

    NASA Technical Reports Server (NTRS)

    Kesseli, James; Saunders, Roger; Batchelder, Gary

    1988-01-01

    Solar Dynamic space power systems are candidate electrical power generating systems for future NASA missions. One of the key components of the solar dynamic power system is the solar receiver/thermal energy storage (TES) subsystem. Receiver development was conducted by NASA in the late 1960's and since then a very limited amount of work has been done in this area. Consequently the state of the art (SOA) receivers designed for the IOC space station are large and massive. The objective of the Advanced Heat Receiver Conceptual Design Study is to conceive and analyze advanced high temperature solar dynamic Brayton and Stirling receivers. The goal is to generate innovative receiver concepts that are half of the mass, smaller, and more efficient than the SOA. It is also necessary that these innovative receivers offer ease of manufacturing, less structural complexity and fewer thermal stress problems. Advanced Brayton and Stirling receiver storage units are proposed and analyzed in this study which can potentially meet these goals.

  12. Theoretical SIS mixer research. Final technical report, 1 June 1990-30 November 1992. [SIS (superconductor-insulator-superconductor)

    SciTech Connect

    Feldman, M.J.

    1993-06-01

    Theoretical research has been conducted to elucidate the basic physics behind the properties of superconductor-insulator-superconductor (SIS) tunnel junction receiving devices. The properties of SIS mixers using nonideal junctions and finite LO power, were determined by analytic expansion of the equations of the quantum theory of mixing, and also by computer simulations of SIS receivers over the entire range of experimental parameters. The result is a new coherent and intuitive picture of SIS mixer behavior. Many of the outstanding mysteries and questions about SIS receivers are resolved, and this contributes greatly to the design and interpretation of SIS mixer experiments. Other calculations show how to achieve sub-quantum noise temperatures in the phase sensitive SIS mixer, an important step towards realization of ultra-low-noise detectors. A simplified model casts doubt on the superlative experimental results reported for the rf-series dc-parallel biased array SIS mixer. Superconductivity; SIS mixer; Submillimeter-wave detection.

  13. Fabrication of advanced design (grooved) cermet anodes

    NASA Astrophysics Data System (ADS)

    Windisch, C. F., Jr.; Huettig, F. R.

    1993-05-01

    Attempts were made to fabricate full-size anodes with advanced, or grooved, design using isostatic pressing, slip casting injection molding. Of the three approaches, isostatic pressing produced an anode with dimensions nearest to the target specifications, without serious macroscopic flaws. This approach is considered the most promising for making advanced anodes for aluminum smelting. However, significant work still remains to optimize the physical properties and microstructure of the anode, both of which were significantly different from that of previous anodes. Injection molding and slip casting yielded anode materials with serious deficiencies, including cracks and holes. Injection molding gave cermet material with the best intrinsic microstructure, i.e., the microstructure of the material between macroscopic flaws was very similar to that of anodes previously made at PNL. The reason for the similarity may have to do with amount of residual binder in the material prior to sintering.

  14. Fabrication of advanced design (grooved) cermet anodes

    SciTech Connect

    Windisch, C.F. Jr.; Huettig, F.R.

    1993-05-01

    Attempts were made to fabricate full-size anodes with advanced, or grooved, design using isostatic pressing, slip casting injection molding. Of the three approaches, isostatic pressing produced an anode with dimensions nearest to the target specifications, without serious macroscopic flaws. This approach is considered the most promising for making advanced anodes for aluminum smelting. However, significant work still remains to optimize the physical properties and microstructure of the anode, both of which were significantly different from that of previous anodes. Injection molding and slip casting yielded anode materials with serious deficiencies, including cracks and holes. Injection molding gave cermet material with the best intrinsic microstructure, i.e., the microstructure of the material between macroscopic flaws was very similar to that of anodes previously made at PNL. Reason for the similarity may have to do with amount of residual binder in the material prior to sintering.

  15. An Integrated Balanced Superconductor-Insulator-Superconductor Heterodyne Mixer on a Silicon Membrane

    NASA Astrophysics Data System (ADS)

    Westig, M. P.; Jacobs, K.; Schultz, M.; Justen, M.; Stutzki, J.; Honingh, C. E.

    2011-03-01

    We have designed and fabricated a 380-520 GHz integrated balanced NbAlAlOxNb superconductor-insulator-superconductor (SIS) heterodyne waveguide mixer for submillimeter astrophysics. The response of the mixer measured with a Fourier transform spectrometer shows excellent agreement with the design. The novelty of our device is that we deposit the complete superconducting mixer circuit (tapered slotline antennas, hybrid coupler, MIM capacitors, SIS junctions, tuning circuits and blocking filters) on top of a 9 μ m silicon membrane. The membrane is held suspended in a waveguide by 2.5 μ m thick gold plated beamleads. We will show that silicon membrane technology and a thorough device design render the integration of SIS devices with larger circuits feasible. This is an important step towards large arrays of mixers. When using an appropriate superconductor technology, these devices are scalable to higher frequencies. We will present the design, fabrication results and first results of heterodyne measurements.

  16. Advanced ISDN satellite designs and experiments

    NASA Technical Reports Server (NTRS)

    Pepin, Gerard R.

    1992-01-01

    The research performed by GTE Government Systems and the University of Colorado in support of the NASA Satellite Communications Applications Research (SCAR) Program is summarized. Two levels of research were undertaken. The first dealt with providing interim services Integrated Services Digital Network (ISDN) satellite (ISIS) capabilities that accented basic rate ISDN with a ground control similar to that of the Advanced Communications Technology Satellite (ACTS). The ISIS Network Model development represents satellite systems like the ACTS orbiting switch. The ultimate aim is to move these ACTS ground control functions on-board the next generation of ISDN communications satellite to provide full-service ISDN satellite (FSIS) capabilities. The technical and operational parameters for the advanced ISDN communications satellite design are obtainable from the simulation of ISIS and FSIS engineering software models of the major subsystems of the ISDN communications satellite architecture. Discrete event simulation experiments would generate data for analysis against NASA SCAR performance measure and the data obtained from the ISDN satellite terminal adapter hardware (ISTA) experiments, also developed in the program. The Basic and Option 1 phases of the program are also described and include the following: literature search, traffic mode, network model, scenario specifications, performance measures definitions, hardware experiment design, hardware experiment development, simulator design, and simulator development.

  17. Advanced surface design for logistics analysis

    NASA Astrophysics Data System (ADS)

    Brown, Tim R.; Hansen, Scott D.

    The development of anthropometric arm/hand and tool models and their manipulation in a large system model for maintenance simulation are discussed. The use of Advanced Surface Design and s-fig technology in anthropometrics, and three-dimensional graphics simulation tools, are found to achieve a good balance between model manipulation speed and model accuracy. The present second generation models are shown to be twice as fast to manipulate as the first generation b-surf models, to be easier to manipulate into various configurations, and to more closely approximate human contours.

  18. Advanced Avionics Breadboard Executive Design and Implementation

    NASA Technical Reports Server (NTRS)

    Adams, L. R.

    1972-01-01

    The advanced avionics breadboard (AAB) executive evolved from an effort to design and develop an avionics system. This executive is unique in that it supervises a triple redundant avionics computer system. Three IBM System 4 Pi/CP computers, operating synchronously and executing identical software, comprise the central processors which route data to and from a data bus via an input/output controller. The executive's basic function is to provide application programs with an efficient software structure within which to perform specific avionics application tasks. Although implemented in a triplex data management system, the AAB executive contains the flexibility to be adapted to other systems with minimal change.

  19. ASDA - Advanced Suit Design Analyzer computer program

    NASA Technical Reports Server (NTRS)

    Bue, Grant C.; Conger, Bruce C.; Iovine, John V.; Chang, Chi-Min

    1992-01-01

    An ASDA model developed to evaluate the heat and mass transfer characteristics of advanced pressurized suit design concepts for low pressure or vacuum planetary applications is presented. The model is based on a generalized 3-layer suit that uses the Systems Integrated Numerical Differencing Analyzer '85 in conjunction with a 41-node FORTRAN routine. The latter simulates the transient heat transfer and respiratory processes of a human body in a suited environment. The user options for the suit encompass a liquid cooled garment, a removable jacket, a CO2/H2O permeable layer, and a phase change layer.

  20. Advanced tracking systems design and analysis

    NASA Technical Reports Server (NTRS)

    Potash, R.; Floyd, L.; Jacobsen, A.; Cunningham, K.; Kapoor, A.; Kwadrat, C.; Radel, J.; Mccarthy, J.

    1989-01-01

    The results of an assessment of several types of high-accuracy tracking systems proposed to track the spacecraft in the National Aeronautics and Space Administration (NASA) Advanced Tracking and Data Relay Satellite System (ATDRSS) are summarized. Tracking systems based on the use of interferometry and ranging are investigated. For each system, the top-level system design and operations concept are provided. A comparative system assessment is presented in terms of orbit determination performance, ATDRSS impacts, life-cycle cost, and technological risk.

  1. Sandwich-format 3D printed microfluidic mixers: a flexible platform for multi-probe analysis

    PubMed Central

    Kise, Drew P; Reddish, Michael J; Dyer, R Brian

    2015-01-01

    We report on a microfluidic mixer fabrication platform that increases the versatility and flexibility of mixers for biomolecular applications. A sandwich-format design allows the application of multiple spectroscopic probes to the same mixer. A polymer spacer is ‘sandwiched’ between two transparent windows, creating a closed microfluidic system. The channels of the mixer are defined by regions in the polymer spacer that lack material and therefore the polymer need not be transparent in the spectral region of interest. Suitable window materials such as CaF2 make the device accessible to a wide range of optical probe wavelengths, from the deep UV to the mid-IR. In this study, we use a commercially available 3D printer to print the polymer spacers to apply three different channel designs into the passive, continuous-flow mixer, and integrated them with three different spectroscopic probes. All three spectroscopic probes are applicable to each mixer without further changes. The sandwich-format mixer coupled with cost-effective 3D printed fabrication techniques could increase the applicability and accessibility of microfluidic mixing to intricate kinetic schemes and monitoring chemical synthesis in cases where only one probe technique proves insufficient. PMID:26855478

  2. Sandwich-format 3D printed microfluidic mixers: a flexible platform for multi-probe analysis

    NASA Astrophysics Data System (ADS)

    Kise, Drew P.; Reddish, Michael J.; Dyer, R. Brian

    2015-12-01

    We report on a microfluidic mixer fabrication platform that increases the versatility and flexibility of mixers for biomolecular applications. A sandwich-format design allows the application of multiple spectroscopic probes to the same mixer. A polymer spacer is ‘sandwiched’ between two transparent windows, creating a closed microfluidic system. The channels of the mixer are defined by regions in the polymer spacer that lack material and therefore the polymer need not be transparent in the spectral region of interest. Suitable window materials such as CaF2 make the device accessible to a wide range of optical probe wavelengths, from the deep UV to the mid-IR. In this study, we use a commercially available 3D printer to print the polymer spacers to apply three different channel designs into the passive, continuous-flow mixer, and integrated them with three different spectroscopic probes. All three spectroscopic probes are applicable to each mixer without further changes. The sandwich-format mixer coupled with cost-effective 3D printed fabrication techniques could increase the applicability and accessibility of microfluidic mixing to intricate kinetic schemes and monitoring chemical synthesis in cases where only one probe technique proves insufficient.

  3. S-I-S mm-wave mixers and detectors

    NASA Astrophysics Data System (ADS)

    Jillie, D. W.; Kroger, H.; Smith, L. N.; Shaw, D. M.

    1983-10-01

    This program is an effort to achieve the ultimate goal of fabricating refractory superconducting S-I-S mixer devices for operation in mm-wave receivers in the quantum mode and in the 8-10 K temperature range. The following progress has been made toward the above goal: (1) development of in-house capability of depositing niobium carbonitride films (Nb (x) N(y) of device quality with transition temperatures to approx. 16 K; (2) development of NbC(x)N(y):aSi:Nb and NbC(x)N(y):Ge:Nb devices of very high quality; (3) fabrication and successful operation of niobium based S-I-S mixer chips; and (4) fabrication and evaluation of aSi and Ge barrier all-NbC(x)N(y) devices. NbC(x)N(y):Ge:Nb devices have been fabricated with chemical vapor deposited (CVD) polycrystalline arsenic-doped germanium barriers. All-Nb-S-I-S mixer chips were fabricated and sent to Goddard Institute for Space Studies to be evaluated. The noise temperature was approx. 60 K and the conversion loss of 5 dB. These results are comparable to Pb alloy junction results. A second-generation mixer was designed by GISS.

  4. Superconducting Nb DHEB Mixer Arrays for Far-Infrared Spectroscopy

    NASA Technical Reports Server (NTRS)

    Gerecht, E.; Reintsema, C. D.; Grossman, E. N.; Betz, A. L.; Boreiko, R. T.

    2001-01-01

    We are developing a heterodyne focal plane array with up to eight elements to study lines of the interstellar medium and planetary atmospheres with frequencies of 2 THz and above. Our fabrication process utilizes selective ion milling techniques to produce Nb Diffusion-Cooled Hot Electron Bolometric (DHEB) mixers from a bilayer thin film of Au/Nb deposited on a silicon substrate. A micro-bridge of 10 nm thick Nb forms the HEB device. The first generation of devices with lateral dimensions of 100 nm by 80 nm were fabricated at the feed of a broadband spiral antenna with a frequency response designed for up to 16 THz. Harmonic multiplier sources becoming available within the next few years should have sufficient power to provide a local-oscillator source for small-format, quasi-optically coupled arrays of these mixers. First generation devices measured at our laboratory have demonstrated a critical temperature (Tc) of 4.8 K with a 0.5 K transition width. These DHEB mixers are expected to have an optimum operational temperature of 1.8-2.0 K. The current four element array mixer block will ultimately be replaced by a dual polarization slot-ring array configuration with up to eight elements.

  5. Double-Balanced Graphene Integrated Mixer with Outstanding Linearity.

    PubMed

    Lyu, Hongming; Wu, Huaqiang; Liu, Jinbiao; Lu, Qi; Zhang, Jinyu; Wu, Xiaoming; Li, Junfeng; Ma, Teng; Niu, Jiebin; Ren, Wencai; Cheng, Huiming; Yu, Zhiping; Qian, He

    2015-10-14

    A monolithic double-balanced graphene mixer integrated circuit (IC) has been successfully designed and fabricated. The IC adopted the cross-coupled resistive mixer topology, integrating four 500 nm-gate-length graphene field-effect transistors (GFETs), four on-chip inductors, and four on-chip capacitors. Passive-first-active-last fabrication flow was developed on 200 mm CMOS wafers. CMOS back-end-of-line processes were utilized to realize most fabrication steps followed by GFET-customized processes. Test results show excellent output spectrum purity with suppressed radio frequency (RF) and local oscillation (LO) signals feedthroughs, and third-order input intercept (IIP3) reaches as high as 21 dBm. The results are compared with a fabricated single-GEFT mixer, which generates IIP3 of 16.5 dBm. Stand-alone 500 nm-gate-length GFETs feature cutoff frequency 22 GHz and maximum oscillation frequency 20.7 GHz RF performance. The double-balanced mixer IC operated with off-chip baluns realizing a print-circuit-board level electronic system. It demonstrates graphene's potential to compete with other semiconductor technologies in RF front-end applications. PMID:26378374

  6. NASA/USRA University advanced design program

    NASA Technical Reports Server (NTRS)

    Lembeck, Michael F.; Prussing, John

    1989-01-01

    The participation of the University of Illinois at Urbana-Champaign in the NASA/USRA University Advanced Design Program for the 1988 to 1989 academic year is reviewed. The University's design project was the Logistics Resupply and Emergency Crew Return System for Space Station Freedom. Sixty-one students divided into eight groups, participated in the spring 1989 semester. A presentation prepared by three students and a graduate teaching assistant for the program's summer conference summarized the project results. Teamed with the NASA Marshall Space Flight Center (MSFC), the University received support in the form of remote telecon lectures, reference material, and previously acquired applications software. In addition, a graduate teaching assistant was awarded a summer 1989 internship at MSFC.

  7. Disposable Diaper Absorbency: Improvements via Advanced Designs.

    PubMed

    Helmes, C Tucker; O'Connor, Robert; Sawyer, Larry; Young, Sharon

    2014-06-24

    Absorbency effectiveness in diapers has improved significantly in recent years with the advent of new ingredient combinations and advanced design features. With these features, many leading products maintain their dryness performance overnight. Considering the importance of holding liquid away from the skin, ongoing research in diaper construction focuses on strategies to increase the effectiveness to capture liquid and help avoid rewetting of infant skin. The layout and design of a disposable diaper allows for distribution of absorbency features where they can provide the optimal benefit. Clinical evidence indicates materials can keep moisture away from the skin in the diapered area, helping maintain proper skin hydration, minimizing irritation, and contributing to reduced rates of diaper rash. PMID:24961785

  8. Measuring advances in HVAC distribution system designs

    SciTech Connect

    Franconi, Ellen

    1998-07-01

    Substantial commercial building energy savings have been achieved by improving the performance of the HVAC distribution system. The energy savings result from distribution system design improvements, advanced control capabilities, and use of variable-speed motors. Yet, much of the commercial building stock remains equipped with inefficient systems. Contributing to this is the absence of a definition for distribution system efficiency as well as the analysis methods for quantifying performance. This research investigates the application of performance indices to assess design advancements in commercial building thermal distribution systems. The index definitions are based on a first and second law of thermodynamics analysis of the system. The second law or availability analysis enables the determination of the true efficiency of the system. Availability analysis is a convenient way to make system efficiency comparisons since performance is evaluated relative to an ideal process. A TRNSYS simulation model is developed to analyze the performance of two distribution system types, a constant air volume system and a variable air volume system, that serve one floor of a large office building. Performance indices are calculated using the simulation results to compare the performance of the two systems types in several locations. Changes in index values are compared to changes in plant energy, costs, and carbon emissions to explore the ability of the indices to estimate these quantities.

  9. Measuring Advances in HVAC Distribution System Design

    SciTech Connect

    Franconi, E.

    1998-05-01

    Substantial commercial building energy savings have been achieved by improving the performance of the HV AC distribution system. The energy savings result from distribution system design improvements, advanced control capabilities, and use of variable-speed motors. Yet, much of the commercial building stock remains equipped with inefficient systems. Contributing to this is the absence of a definition for distribution system efficiency as well as the analysis methods for quantifying performance. This research investigates the application of performance indices to assess design advancements in commercial building thermal distribution systems. The index definitions are based on a first and second law of thermodynamics analysis of the system. The second law or availability analysis enables the determination of the true efficiency of the system. Availability analysis is a convenient way to make system efficiency comparisons since performance is evaluated relative to an ideal process. A TRNSYS simulation model is developed to analyze the performance of two distribution system types, a constant air volume system and a variable air volume system, that serve one floor of a large office building. Performance indices are calculated using the simulation results to compare the performance of the two systems types in several locations. Changes in index values are compared to changes in plant energy, costs, and carbon emissions to explore the ability of the indices to estimate these quantities.

  10. Advanced Neutron Source radiological design criteria

    SciTech Connect

    Westbrook, J.L.

    1995-08-01

    The operation of the proposed Advanced Neutron Source (ANS) facility will present a variety of radiological protection problems. Because it is desired to design and operate the ANS according to the applicable licensing standards of the Nuclear Regulatory Commission (NRC), it must be demonstrated that the ANS radiological design basis is consistent not only with state and Department of Energy (DOE) and other usual federal regulations, but also, so far as is practicable, with NRC regulations and with recommendations of such organizations as the Institute of Nuclear Power Operations (INPO) and the Electric Power Research Institute (EPRI). Also, the ANS radiological design basis is in general to be consistent with the recommendations of authoritative professional and scientific organizations, specifically the National Council on Radiation Protection and Measurements (NCRP) and the International Commission on Radiological Protection (ICRP). As regards radiological protection, the principal goals of DOE regulations and guidance are to keep occupational doses ALARA [as low as (is) reasonably achievable], given the current state of technology, costs, and operations requirements; to control and monitor contained and released radioactivity during normal operation to keep public doses and releases to the environment ALARA; and to limit doses to workers and the public during accident conditions. Meeting these general design objectives requires that principles of dose reduction and of radioactivity control by employed in the design, operation, modification, and decommissioning of the ANS. The purpose of this document is to provide basic radiological criteria for incorporating these principles into the design of the ANS. Operations, modification, and decommissioning will be covered only as they are affected by design.

  11. Advanced burner test reactor preconceptual design report.

    SciTech Connect

    Chang, Y. I.; Finck, P. J.; Grandy, C.; Cahalan, J.; Deitrich, L.; Dunn, F.; Fallin, D.; Farmer, M.; Fanning, T.; Kim, T.; Krajtl, L.; Lomperski, S.; Moisseytsev, A.; Momozaki, Y.; Sienicki, J.; Park, Y.; Tang, Y.; Reed, C.; Tzanos, C; Wiedmeyer, S.; Yang, W.; Chikazawa, Y.; JAEA

    2008-12-16

    advanced fuel cycle; (2) To qualify the transuranics-containing fuels and advanced structural materials needed for a full-scale ABR; and (3) To support the research, development and demonstration required for certification of an ABR standard design by the U.S. Nuclear Regulatory Commission. The ABTR should also address the following additional objectives: (1) To incorporate and demonstrate innovative design concepts and features that may lead to significant improvements in cost, safety, efficiency, reliability, or other favorable characteristics that could promote public acceptance and future private sector investment in ABRs; (2) To demonstrate improved technologies for safeguards and security; and (3) To support development of the U.S. infrastructure for design, fabrication and construction, testing and deployment of systems, structures and components for the ABRs. Based on these objectives, a pre-conceptual design of a 250 MWt ABTR has been developed; it is documented in this report. In addition to meeting the primary and additional objectives listed above, the lessons learned from fast reactor programs in the U.S. and worldwide and the operating experience of more than a dozen fast reactors around the world, in particular the Experimental Breeder Reactor-II have been incorporated into the design of the ABTR to the extent possible.

  12. Advanced Neutron Sources: Plant Design Requirements

    SciTech Connect

    Not Available

    1990-07-01

    The Advanced Neutron Source (ANS) is a new, world class facility for research using hot, thermal, cold, and ultra-cold neutrons. At the heart of the facility is a 350-MW{sub th}, heavy water cooled and moderated reactor. The reactor is housed in a central reactor building, with supporting equipment located in an adjoining reactor support building. An array of cold neutron guides fans out into a large guide hall, housing about 30 neutron research stations. Office, laboratory, and shop facilities are included to provide a complete users facility. The ANS is scheduled to begin operation at the Oak Ridge National Laboratory at the end of the decade. This Plant Design Requirements document defines the plant-level requirements for the design, construction, and operation of the ANS. This document also defines and provides input to the individual System Design Description (SDD) documents. Together, this Plant Design Requirements document and the set of SDD documents will define and control the baseline configuration of the ANS.

  13. Phase C Flygt Mixer Test Results

    SciTech Connect

    Poirier, M.R.

    1999-06-08

    The Savannah River Site (SRS) teamed with the Pacific Northwest National Laboratory (PNNL), Oak Ridge National Laboratory (ORNL), and ITT Flygt Corporation to conduct a test program evaluating shrouded axial propeller mixers (Flygt mixers) for heel removal in SRS Tank 19. SRS is identifying and investigating techniques to remove sludge heels from waste tanks such as Tank 19.

  14. Flashback resistant pre-mixer assembly

    DOEpatents

    Laster, Walter R.; Gambacorta, Domenico

    2012-02-14

    A pre-mixer assembly associated with a fuel supply system for mixing of air and fuel upstream from a main combustion zone in a gas turbine engine. The pre-mixer assembly includes a swirler assembly disposed about a fuel injector of the fuel supply system and a pre-mixer transition member. The swirler assembly includes a forward end defining an air inlet and an opposed aft end. The pre-mixer transition member has a forward end affixed to the aft end of the swirler assembly and an opposed aft end defining an outlet of the pre-mixer assembly. The aft end of the pre-mixer transition member is spaced from a base plate such that a gap is formed between the aft end of the pre-mixer transition member and the base plate for permitting a flow of purge air therethrough to increase a velocity of the air/fuel mixture exiting the pre-mixer assembly.

  15. Submersible canned motor mixer pump

    DOEpatents

    Guardiani, R.F.; Pollick, R.D.

    1997-10-07

    A mixer pump is described used in a waste tank for mobilizing high-level radioactive liquid waste having a column assembly containing power cables, a motor housing with electric motor means which includes a stator can of a stator assembly and a rotor can of a rotor assembly, and an impeller assembly with an impeller connected to a shaft of the rotor assembly. The column assembly locates the motor housing with the electric motor means adjacent to the impeller which creates an hydraulic head, and which forces the liquid waste into the motor housing to cool the electric motor means and to lubricate radial and thrust bearing assemblies. Hard-on-hard bearing surfaces of the bearing assemblies and a ring assembly between the impeller and electric motor means act to grind down large particles in the liquid waste flow. These larger particles are received in slots in the static bearing members of the radial bearing assemblies. Only solid waste particles smaller than the clearances in the system can pass there through, thereby resisting damage to and the interruption of the operation of the mixer pump. 10 figs.

  16. Submersible canned motor mixer pump

    DOEpatents

    Guardiani, Richard F.; Pollick, Richard D.

    1997-01-01

    A mixer pump used in a waste tank for mobilizing high-level radioactive liquid waste having a column assembly containing power cables, a motor housing with electric motor means which includes a stator can of a stator assembly and a rotor can of a rotor assembly, and an impeller assembly with an impeller connected to a shaft of the rotor assembly. The column assembly locates the motor housing with the electric motor means adjacent to the impeller which creates an hydraulic head, and which forces the liquid waste into the motor housing to cool the electric motor means and to lubricate radial and thrust bearing assemblies. Hard-on-hard bearing surfaces of the bearing assemblies and a ring assembly between the impeller and electric motor means act to grind down large particles in the liquid waste flow. These larger particles are received in slots in the static bearing members of the radial bearing assemblies. Only solid waste particles smaller than the clearances in the system can pass therethrough, thereby resisting damage to and the interruption of the operation of the mixer pump.

  17. Sideband separating mixer for 600-720 GHz for ALMA band 9 upgrade

    NASA Astrophysics Data System (ADS)

    Khudchenko, Andrey; Hesper, Ronald; Baryshev, Andrey; Gerlofma, Gerrit; Barkhof, Jan; Adema, Joost; Mena, Patricio; Klapwijk, Teun; Spaans, Marco

    2012-09-01

    For high-frequency observational bands like ALMA (Atacama Large Millimeter Array) Band 9 (600—720 GHz), which tend to be dominated by atmospheric noise, implementation of sideband-separating mixers can reduce, up to a factor of two, the integration time needed to reach a certain signal-to-noise ratio for spectral line observations. Because of very high oversubscription factor for observation in ALMA Band 9, an upgrade of the current Double Sideband (DSB) mixer to a Two Sideband (2SB) configuration is a promising option for future ALMA development. Here we present a developed 2SB mixer and a modified cartridge design. The 2SB mixer includes a waveguide RF hybrid block, which have been produced on a micro-milling machine and equipped with standard Band 9 SIS mixer devices. These two SIS mixers have been separately tested in DSB mode. The SSB noise temperature is within the ALMA requirements of 336 K over 80% of the band, and 500 K over the entire band. The 2SB mixer has the sideband rejection ratio better than 12 dB over the full RF band, which is also well within the ALMA specifications of 10 dB.

  18. Space Station galley design

    NASA Technical Reports Server (NTRS)

    Trabanino, Rudy; Murphy, George L.; Yakut, M. M.

    1986-01-01

    An Advanced Food Hardware System galley for the initial operating capability (IOC) Space Station is discussed. Space Station will employ food hardware items that have never been flown in space, such as a dishwasher, microwave oven, blender/mixer, bulk food and beverage dispensers, automated food inventory management, a trash compactor, and an advanced technology refrigerator/freezer. These new technologies and designs are described and the trades, design, development, and testing associated with each are summarized.

  19. Preliminary design studies of an advanced general aviation aircraft

    NASA Technical Reports Server (NTRS)

    1991-01-01

    Preliminary design studies are presented for an advanced general aviation aircraft. Advanced guidance and display concepts, laminar flow, smart structures, fuselage and wing structural design and manufacturing, and preliminary configuration design are discussed. This project was conducted as a graduate level design class under the auspices of the KU/NASA/USRA Advanced Design Program in Aeronautics. The results obtained during the fall semester of 1990 (Phase 1) and the spring semester of 1991 (Phase 2) are presented.

  20. Conceptual design study of advanced acoustic-composite nacelles

    NASA Technical Reports Server (NTRS)

    Nordstrom, K. E.; Marsh, A. H.; Sargisson, D. F.

    1975-01-01

    Conceptual studies were conducted to assess the impact of incorporating advanced technologies in the nacelles of a current wide-bodied transport and an advanced technology transport. The improvement possible in the areas of fuel consumption, flyover noise levels, airplane weight, manufacturing costs, and airplane operating cost were evaluated for short and long-duct nacelles. Use of composite structures for acoustic duct linings in the fan inlet and exhaust ducts was considered as well as for other nacelle components. For the wide-bodied transport, the use of a long-duct nacelle with an internal mixer nozzle in the primary exhaust showed significant improvement in installed specific fuel consumption and airplane direct operating costs compared to the current short-duct nacelle. The long-duct mixed-flow nacelle is expected to achieve significant reductions in jet noise during takeoff and in turbo-machinery noise during landing approach. Recommendations were made of the technology development needed to achieve the potential fuel conservation and noise reduction benefits.

  1. Advanced Neutron Source: Plant Design Requirements

    SciTech Connect

    Not Available

    1990-07-01

    The Advanced Neutron Source will be a new world-class facility for research using hot, thermal, cold, and ultra-cold neutrons. The heart of the facility will be a 330-MW (fission), heavy-water cooled and heavy-water moderated reactor. The reactor will be housed in a central reactor building, with supporting equipment located in an adjoining reactor support building. An array of cold neutron guides will fan out into a large guide hall, housing about 30 neutron research stations. Appropriate office, laboratory, and shop facilities will be included to provide a complete facility for users. The ANS is scheduled to begin operation at the Oak Ridge National Laboratory early in the next decade. This PDR document defines the plant-level requirements for the design, construction, and operation of ANS. It also defines and provides input to the individual System Design Description (SDD) documents. Together, this PDR document and the set of SDD documents will define and control the baseline configuration of ANS.

  2. 670-GHz Schottky Diode-Based Subharmonic Mixer with CPW Circuits and 70-GHz IF

    NASA Technical Reports Server (NTRS)

    Chattopadhyay, Goutam; Schlecht, Erich T.; Lee, Choonsup; Lin, Robert H.; Gill, John J.; Mehdi, Imran; Sin, Seth; Deal, William; Loi, Kwok K.; Nam, Peta; Rodriguez, Bryan

    2012-01-01

    GaAs-based, sub-harmonically pumped Schottky diode mixers offer a number of advantages for array implementation in a heterodyne receiver system. Since the radio frequency (RF) and local oscillator (LO) signals are far apart, system design becomes much simpler. A proprietary planar GaAs Schottky diode process was developed that results in very low parasitic anodes that have cutoff frequencies in the tens of terahertz. This technology enables robust implementation of monolithic mixer and frequency multiplier circuits well into the terahertz frequency range. Using optical and e-beam lithography, and conventional epitaxial layer design with innovative usage of GaAs membranes and metal beam leads, high-performance terahertz circuits can be designed with high fidelity. All of these mixers use metal waveguide structures for housing. Metal machined structures for RF and LO coupling hamper these mixers to be integrated in multi-pixel heterodyne array receivers for spectroscopic and imaging applications. Moreover, the recent developments of terahertz transistors on InP substrate provide an opportunity, for the first time, to have integrated amplifiers followed by Schottky diode mixers in a heterodyne receiver at these frequencies. Since the amplifiers are developed on a planar architecture to facilitate multi-pixel array implementation, it is quite important to find alternative architecture to waveguide-based mixers.

  3. Alternate paddle configuration for improved wear resistance in the saltstone mixer

    SciTech Connect

    Reigel, M.; Fowley, M.

    2013-09-23

    The Saltstone Production Facility has a 10-inch Readco-Kurimoto continuous mixer that mixes the premix dry feeds and low-level waste salt solution to make fresh (uncured) saltstone. Inspection of the mixer in January 2013 showed significant wear on the third, fourth and fifth paddle pairs after the conveying augers. A 2-inch Readco-Kurimoto continuous mixer was used to test alternate paddle configurations for use in the 10-inch mixer to decrease the wear rate on the paddles. Two wear tests were conducted to investigate a method of reducing wear on the mixer paddles. The first test (wear test 2a) had a paddle configuration similar to the currently installed 10-inch mixer in the SPF. This test established baseline wear. The second test (wear test 2b) had a reconfigured paddle arrangement that replaced the flat paddles with helical paddles for paddle pairs 2 - 6 and aligned paddle pair 1 with the augers. The intent of the reconfiguration was to more effectively convey the partially wetted dry feeds through the transition region and into the liquid feed where paddle wear is reduced due to dry feeds and salt solution being mixed at the intended water to premix ratio. The design of the helical paddles provides conveyance through the transition region to the liquid feed inlet. The alignment with the auger is aimed to provide a smoother transition (minimizing the discontinuity between the auger and paddle pair 1) into the downstream paddles. A soft metal with low wear resistance (6000 series aluminum) was used for the wear testing paddles to determine wear patterns while minimizing run time and maximizing wear rate. For the two paddle configurations tested using the scaled 2-inch Readco-Kurimoto continuous mixer, with the first six paddles after the augers replaced by the wear paddles and the remaining paddles were stainless steel. Since the 10-inch SPF mixer is designed with the liquid inlet centered over paddle pairs 5 and 6, the scaled 2-inch mixer was configured the

  4. Advances in fuel cell vehicle design

    NASA Astrophysics Data System (ADS)

    Bauman, Jennifer

    Factors such as global warming, dwindling fossil fuel reserves, and energy security concerns combine to indicate that a replacement for the internal combustion engine (ICE) vehicle is needed. Fuel cell vehicles have the potential to address the problems surrounding the ICE vehicle without imposing any significant restrictions on vehicle performance, driving range, or refuelling time. Though there are currently some obstacles to overcome before attaining the widespread commercialization of fuel cell vehicles, such as improvements in fuel cell and battery durability, development of a hydrogen infrastructure, and reduction of high costs, the fundamental concept of the fuel cell vehicle is strong: it is efficient, emits zero harmful emissions, and the hydrogen fuel can be produced from various renewable sources. Therefore, research on fuel cell vehicle design is imperative in order to improve vehicle performance and durability, increase efficiency, and reduce costs. This thesis makes a number of key contributions to the advancement of fuel cell vehicle design within two main research areas: powertrain design and DC/DC converters. With regards to powertrain design, this research first analyzes various powertrain topologies and energy storage system types. Then, a novel fuel cell-battery-ultracapacitor topology is presented which shows reduced mass and cost, and increased efficiency, over other promising topologies found in the literature. A detailed vehicle simulator is created in MATLAB/Simulink in order to simulate and compare the novel topology with other fuel cell vehicle powertrain options. A parametric study is performed to optimize each powertrain and general conclusions for optimal topologies, as well as component types and sizes, for fuel cell vehicles are presented. Next, an analytical method to optimize the novel battery-ultracapacitor energy storage system based on maximizing efficiency, and minimizing cost and mass, is developed. This method can be applied

  5. Mixing characteristics of mixers in flow analysis. Application to two-dimensional detection in ion chromatography.

    PubMed

    Liao, Hongzhu; Dasgupta, Purnendu K; Srinivasan, Kannan; Liu, Yan

    2015-01-01

    Three mixer designs, a back-flow tee mixer (BT), an end-blocked membrane tee mixer (EMT), and a tubular membrane mixer (TM), were fabricated and compared to three commercially available mixers, Visco-Jet Micro mixer (VJM) and HS binary tee mixer with 2 and 10 μL volume (HS-2 and HS-10) mixing cartridges. Internal volumes ranged from 8.3 to 20.3 μL. Performance characteristics were evaluated by the Villermaux-Dushman reaction, noise in baseline conductance upon mixing an electrolyte solution with water, and dispersion/relative dispersion of an injected solute. No single characteristic would uniquely qualify a particular device. In typical postcolumn use when a small reagent flow is added to a principal flow stream using a low-pulsation high-end chromatographic pump, with the worst of these mixers, imperfect mixing accounted for 99.6% of the observed noise. EMT, BT, and TM with asymmetric inlets provided better mixing performances relative to VJM, HS-2, and HS-10 with symmetric inlet ports, especially when the secondary liquid flow rate was much lower than the principal stream-flow rate. Dispersion per unit residence time was singularly large for HS-2. Based on its mixing efficiency and small dispersion, the BT design was found to be the best for practicing postcolumn reaction. As an illustrative application, this was then used to introduce electrogenerated LiOH in a suppressed ion chromatography system to perform sensitive detection of weak acids in a second dimension. PMID:25426864

  6. Mixing Study in a Multi-dimensional Motion Mixer

    NASA Astrophysics Data System (ADS)

    Shah, R.; Manickam, S. S.; Tomei, J.; Bergman, T. L.; Chaudhuri, B.

    2009-06-01

    Mixing is an important but poorly understood aspect in petrochemical, food, ceramics, fertilizer and pharmaceutical processing and manufacturing. Deliberate mixing of granular solids is an essential operation in the production of industrial powder products usually constituted from different ingredients. The knowledge of particle flow and mixing in a blender is critical to optimize the design and operation. Since performance of the product depends on blend homogeneity, the consequence of variability can be detrimental. A common approach to powder mixing is to use a tumbling blender, which is essentially a hollow vessel horizontally attached to a rotating shaft. This single axis rotary blender is one of the most common batch mixers among in industry, and also finds use in myriad of application as dryers, kilns, coaters, mills and granulators. In most of the rotary mixers the radial convection is faster than axial dispersion transport. This slow dispersive process hinders mixing performance in many blending, drying and coating applications. A double cone mixer is designed and fabricated which rotates around two axes, causing axial mixing competitive to its radial counterpart. Discrete Element Method (DEM) based numerical model is developed to simulate the granular flow within the mixer. Digitally recorded mixing states from experiments are used to fine tune the numerical model. Discrete pocket samplers are also used in the experiments to quantify the characteristics of mixing. A parametric study of the effect of vessel speeds, relative rotational speed (between two axes of rotation), on the granular mixing is investigated by experiments and numerical simulation. Incorporation of dual axis rotation enhances axial mixing by 60 to 85% in comparison to single axis rotation.

  7. Mixer assembly for a gas turbine engine having a pilot mixer with a corner flame stabilizing recirculation zone

    NASA Technical Reports Server (NTRS)

    Dai, Zhongtao (Inventor); Cohen, Jeffrey M. (Inventor); Fotache, Catalin G. (Inventor)

    2012-01-01

    A mixer assembly for a gas turbine engine is provided, including a main mixer, and a pilot mixer having an annular housing in which a corner is formed between an aft portion of the housing and a bulkhead wall in which a corner recirculation zone is located to stabilize and anchor the flame of the pilot mixer. The pilot mixer can further include features to cool the annular housing, including in the area of the corner recirculation zone.

  8. Detailed evaluation of the performance of microfluidic T mixers using fluorescence and ultraviolet resonance Raman spectroscopy

    NASA Astrophysics Data System (ADS)

    Masca, Sergiu I.; Rodriguez-Mendieta, Iñigo R.; Friel, Claire T.; Radford, Sheena E.; Smith, D. Alastair

    2006-05-01

    A reliable device that produces efficient mixing with a short dead time has enormous utility in the kinetic analysis of biochemical and chemical processes. We have designed two different T mixers that use moderate flow rates (0.2-0.4ml/s), can monitor reactions up to several milliseconds, and achieve mixing times as low as 20μs. The two mixers are easy to build and dismantle, reliable, and can perform hundreds of experiments without blocking. The first mixer comprises a stainless steel block, containing a microchannel, glued to a quartz cuvette, containing a 200×200μm2 observation channel defining a conventional T mixer. The reactions are monitored by imaging the length of the observation channel onto a charge-coupled device camera. In the second mixer the entire T (200×200μm2 internal cross section) is contained within a 40-mm-long quartz cuvette. We have adopted a novel approach to controlling the entrance channel bore by inserting a stainless steel wire in order to increase the linear speed of the impinging fluids. Using a dye to visualize the flow profile inside the second T mixer, it was shown that in this T geometry segregation of the reactants is observed in the junction between the inlet channels and the observation channel (T junction) and mixing occurs entirely in the observation channel. We thoroughly tested the two mixers through several kinetic reactions using both fluorescence and ultraviolet resonance Raman spectroscopy measurements. We show that both mixers provide efficient mixing with nominal dead times (using 1:10 v /v dilution), calculated using the quenching of the fluorescence of N-acetyl-L-tryptophanamide by N-bromosuccinimide, of 200±20 and 100±10μs, for each mixer, respectively. However, the ability to monitor within the inlet channels and the entire observation channel of the second mixer shows that this standard approach to estimating the dead time is artifactual, since it relies on assuming a constant flow speed throughout the

  9. A Dual Polarized Quasi-Optical SIS Mixer at 550-GHz

    NASA Technical Reports Server (NTRS)

    Chattopadhyay, Goutam; Miller, David; LeDuc, Henry G.; Zmuidzinas, Jonas

    2000-01-01

    We describe the design, fabrication, and the performance of a low-noise dual-polarized quasi-optical superconductor insulator superconductor (SIS) mixer at 550 GHz. The mixer utilizes a novel cross-slot antenna on a hyperhemispherical substrate lens, two junction tuning circuits, niobium trilayer junctions, and an IF circuit containing a lumped element 180 deg hybrid. The antenna consists of an orthogonal pair of twin-slot antennas, and has four feed points, two for each polarization. Each feed point is coupled to a two-junction SIS mixer. The 180 deg IF hybrid is implemented using a lumped element/microstrip circuit located inside the mixer block. Fourier transform spectrometer (FTS) measurements of the mixer frequency response show good agreement with computer simulations. The measured co-polarized and cross-polarized patterns for both polarizations also agree with the theoretical predictions. The noise performance of the dual-polarized mixer is excellent, giving uncorrected receiver noise temperature of better than 115 K (DSB) at 528 GHz for both the polarizations.

  10. Performance of NbN superconductive tunnel junctions as SIS mixers at 205 GHz

    NASA Technical Reports Server (NTRS)

    Mcgrath, W. R.; Stern, J. A.; Javadi, H. H. S.; Cypher, S. R.; Hunt, B. D.

    1991-01-01

    Small area (less than 1 sq micron), high-current-density NbN/MgO/NbN tunnel junctions with I-V characteristics suitable for high-frequency mixers have been fabricated. Mesa-geometry junctions with an area of about 1 sq micron and critical current density of 5-10 kA/sq cm are integrated with superconducting microstrip lines designed to resonate out the junction capacitance. A study was made of the mixer gain and noise performance near 205 GHz as a function of the inductance provided by the microstrip line. This has confirmed, at a high millimeter-wave frequency, values of junction capacitance of 85 fF/sq micron and recently measured values of a magnetic penetration depth of 380 nm. Mixer noise temperatures as low as 134 K at 1.5 K have been obtained for properly tuned junctions. A significant improvement in mixer performance on cooling from 4.2 K to 1.5 K was observed. Edge-geometry junctions with an area of 0.3 sq microns and critical current density of 18-25 kA/sq cm have also been fabricated. These junctions give a mixer noise temperature of 145 K at 4.2 K without the use of integrated tuning elements. These are the best results ever achieved for NbN-based SIS mixers.

  11. Advanced technology's impact on compressor design and development - A perspective

    NASA Technical Reports Server (NTRS)

    Ball, Calvin L.

    1989-01-01

    A historical perspective of the impact of advanced technologies on compression system design and development for aircraft gas turbine applications is presented. A bright view of the future is projected in which further advancements in compression system technologies will be made. These advancements will have a significant impact on the ability to meet the ever-more-demanding requirements being imposed on the propulsion system for advanced aircraft. Examples are presented of advanced compression system concepts now being studied. The status and potential impact of transitioning from an empirically derived design system to a computationally oriented system are highlighted. A current NASA Lewis Research Center program to enhance this transitioning is described.

  12. Advanced technologies impact on compressor design and development: A perspective

    NASA Technical Reports Server (NTRS)

    Ball, Calvin L.

    1989-01-01

    A historical perspective of the impact of advanced technologies on compression system design and development for aircraft gas turbine applications is presented. A bright view of the future is projected in which further advancements in compression system technologies will be made. These advancements will have a significant impact on the ability to meet the ever-more-demanding requirements being imposed on the propulsion system for advanced aircraft. Examples are presented of advanced compression system concepts now being studied. The status and potential impact of transitioning from an empirically derived design system to a computationally oriented system are highlighted. A current NASA Lewis Research Center program to enhance this transitioning is described.

  13. Low Noise SIS Mixer for the Frequency above 1 THz

    NASA Astrophysics Data System (ADS)

    Karpov, Alexander; Miller, D.; Zmuidzinas, J.; Stern, J. A.; Bumble, B.; Leduc, H. G.

    We developed a SIS mixer for the 1.1-1.25 THz band of the heterodyne receiver of Herschel space observatory. Our approach may be used up to 1.6 THz. The quasi-optical SIS mixer has two NbN/AlN/Nb junctions with the critical current 30-50 kA/cm2 and the gap voltage of 3.4 mV. The tuning circuit integrated with SIS junction has the base electrode of Nb and a gold wire layer. This approach simplifies the SIS junction technology, compared to a design using NbTiN base electrode. The junction base electrode and the ground of the tuning micro strip circuit are formed in one step. The frequency of operation of the mixer is well above the gap frequency of Nb, and it behaves here as a normal metal. The resistivity of Nb at the critical temperature of 0.2 mOhm cm is below the resistivity of the best normal metal films. The measured receiver noise temperature is below 600 K.

  14. Electrochemical cell apparatus having an integrated reformer-mixer nozzle-mixer diffuser

    DOEpatents

    Shockling, L.A.

    1991-09-10

    An electrochemical apparatus is made having a generator section containing electrochemical cells, a fresh gaseous feed fuel inlet, a gaseous feed oxidant inlet, and at least one hot gaseous spent fuel recirculation channel, where the spent fuel recirculation channel, passes from the generator chamber to combine with the fresh feed fuel inlet to form a reformable mixture, where a reforming chamber contains an outer portion containing reforming material, an inner portion preferably containing a mixer nozzle and a mixer-diffuser, and a middle portion for receiving spent fuel, where the mixer nozzle and mixer-diffuser are preferably both within the reforming chamber and substantially exterior to the main portion of the apparatus, where the reformable mixture flows up and then backward before contacting the reforming material, and the mixer nozzle can operate below 400 C. 1 figure.

  15. Electrochemical cell apparatus having an integrated reformer-mixer nozzle-mixer diffuser

    DOEpatents

    Shockling, Larry A.

    1991-01-01

    An electrochemical apparatus (10) is made having a generator section (22) containing electrochemical cells (16), a fresh gaseous feed fuel inlet (28), a gaseous feed oxidant inlet (30), and at least one hot gaseous spent fuel recirculation channel (46), where the spent fuel recirculation channel (46), passes from the generator chamber (22) to combine with the fresh feed fuel inlet (28) to form a reformable mixture, where a reforming chamber (54) contains an outer portion containing reforming material (56), an inner portion preferably containing a mixer nozzle (50) and a mixer-diffuser (52), and a middle portion (64) for receiving spent fuel, where the mixer nozzle (50) and mixer-diffuser (52) are preferably both within the reforming chamber (54) and substantially exterior to the main portion of the apparatus, where the reformable mixture flows up and then backward before contacting the reforming material (56), and the mixer nozzle (50) can operate below 400.degree. C.

  16. Magnetic suspension and balance system advanced study, 1989 design

    NASA Technical Reports Server (NTRS)

    Boom, Roger W.; Eyssa, Y. M.; Abdelsalam, Moustafa K.; Mcintosh, Glen E.

    1991-01-01

    The objectives are to experimentally confirm several advanced design concepts on the Magnetic Suspension and Balance Systems (MSBS). The advanced design concepts were identified as potential improvements by Madison Magnetics, Inc. (MMI) during 1984 and 1985 studies of an MSBS utilizing 14 external superconductive coils and a superconductive solenoid in an airplane test model suspended in a wind tunnel. This study confirmed several advanced design concepts on magnetic suspension and balance systems. The 1989 MSBS redesign is based on the results of these experiments. Savings of up to 30 percent in supporting magnet ampere meters and 50 percent in energy stored over the 1985 design were achieved.

  17. The Advanced Light Source: Technical Design

    SciTech Connect

    Authors, Various

    1984-05-01

    The Advanced Light Source (ALS) is a synchrotron radiation source consisting of a 50-MeV linear accelerator, a 1.3-GeV 'booster' synchrotron, a 1.3-GeV electron storage ring, and a number of photon beam lines, as shown in Figure 1. As an introduction to a detailed description of the Advanced Light Source, this section provides brief discussions on the characteristics of synchrotron radiation and on the theory of storage rings. Appendix A contents: Introduction to Synchrotron-Radiation Sources; Storage Ring; Injection System; Control System; Insertion Devices; Photon Beam Lines; and References.

  18. Advanced integrated solution for MEMS design

    NASA Astrophysics Data System (ADS)

    Liateni, Karim; Moulinier, David; Affour, Bachar; Boutamine, H.; Karam, Jean Michel; Veychard, D.; Courtois, Bernard; Cao, Ariel D.

    1999-03-01

    This paper presents a fully integrated solution for the development of Micro Electro Mechanical Systems which covers component libraries, design tools and designs methodologies which are used in conjunction with conventional design automation tools. This solutio enables system houses in wireless and optical communications and consumers electronics markets to reduce their internal development costs and significantly accelerate their product development cycles.

  19. Advances in technologies and study design

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Completion of the initial draft sequence of the human genome was the proving ground for and has ushered in significant advancements in technology of increasing sophistication and ever increasing amounts of data. Often, this combination has a multiplicative effect of stimulating research groups to co...

  20. Balanced Waveguide HEB Mixer for APEX 1.3 THz receiver

    NASA Astrophysics Data System (ADS)

    Meledin, Denis; Pantaleev, Miroslav; Pavolotsky, Alexey; Risacher, Christophe; Perez Robles, Victor A.; Belitsky, Victor; Drakinskiy, Vladimir; Cherednichenko, Sergey

    2005-05-01

    We present results on the design and construction of a waveguide balanced Hot Electron Bolometer (HEB) Terahertz mixer for Atacama Pathfinder EXperiment (APEX), band T2 covering 1250-1390 GHz frequency range. In the proposed design, a waveguide balanced mixer is realized using a quadrature scheme. The two identical HEB elements are integrated with RF choke filters, DC-bias, IF circuitry, and fabricated from 4 nm thick NbN film deposited on a crystalline quartz substrate with dimensions of 1100 μm×70 μm × 17 μm. We have designed and fabricated an input 3 dB quadrature waveguide hybrid. For its fabrication, we use micromachining approach to achieve low insertion loss and symmetrical division of the RF and local oscillator (LO) power within the band of interest. We plan to use two HEB mixer configurations with different probe impedance values of 55, 70 Ohm within 1250-1390 GHz frequency range.

  1. A mixer design for the pigtail braid

    NASA Astrophysics Data System (ADS)

    Binder, B. J.; Cox, S. M.

    2008-01-01

    The stirring of a body of viscous fluid using multiple stirring rods is known to be particularly effective when the rods trace out a path corresponding to a nontrivial mathematical braid. The optimal braid is the so-called "pigtail braid", in which three stirring rods execute the usual "over-under" motion associated with braiding (plaiting) hair. We show how to achieve this optimal braiding motion straightforwardly: one stirring rod is driven in a figure-of-eight motion, while the other two rods are baffles, which rotate episodically about their common centre. We also explore the extent to which the physical baffles may be replaced by flow structures (such as periodic islands).

  2. Quantum limited quasiparticle mixers at 100 GHz

    SciTech Connect

    Mears, C.A; Hu, Qing; Richards, P.L. ); Worsham, A.H.; Prober, D.E. . Dept. of Applied Physics); Raeisaenen, A.V. . Radio Lab.)

    1990-09-01

    We have made accurate measurements of the noise and gain of superconducting-insulating-superconducting (SIS) mixers employing small area (1{mu}m{sup 2}) Ta/Ta{sub 2}O{sub 5}/Pb{sub 0.9}Bi{sub 0.1} tunnel junctions. We have measured an added mixer noise of 0.61 +/{minus} 0.31 quanta at 95.0 GHz, which is within 25 percent of the quantum limit of 0.5 quanta. We have carried out a detailed comparison between theoretical predictions of the quantum theory of mixing and experimentally measured noise and gain. We used the shapes of I-V curves pumped at the upper and lower sideband frequencies to deduce values of the embedding admittances at these frequencies. Using these admittances, the mixer noise and gain predicted by quantum theory are in excellent agreement with experiment. 21 refs., 9 figs.

  3. Advances in Design-Based Research

    ERIC Educational Resources Information Center

    Svihla, Vanessa

    2014-01-01

    Design-based research (DBR) is a core methodology of the Learning Sciences. Historically rooted as a movement away from the methods of experimental psychology, it is a means to develop "humble" theory that takes into account numerous contextual effects for understanding how and why a design supported learning. DBR involves iterative…

  4. Electrochemical cell apparatus having an exterior fuel mixer nozzle

    DOEpatents

    Reichner, Philip; Doshi, Vinod B.

    1992-01-01

    An electrochemical apparatus (10) is made having a generator section (22) containing electrochemical cells (16), a fresh gaseous feed fuel inlet (28), a gaseous feed oxidant inlet (30), and at least one hot gaseous spent fuel recirculation channel (46), where the spent fuel recirculation channel (46), a portion of which is in contact with the outside of a mixer chamber (52), passes from the generator chamber (22) to combine with the fresh feed fuel inlet (28) at the entrance to the mixer chamber, and a mixer nozzle (50) is located at the entrance to the mixer chamber, where the mixer chamber (52) connects with the reforming chamber (54), and where the mixer-diffuser chamber (52) and mixer nozzle (50) are exterior to and spaced apart from the combustion chamber (24), and the generator chamber (22), and the mixer nozzle (50) can operate below 400.degree. C.

  5. Electrochemical cell apparatus having an exterior fuel mixer nozzle

    DOEpatents

    Reichner, P.; Doshi, V.B.

    1992-12-08

    An electrochemical apparatus is made having a generator section containing electrochemical cells, a fresh gaseous feed fuel inlet, a gaseous feed oxidant inlet, and at least one hot gaseous spent fuel recirculation channel, where the spent fuel recirculation channel, a portion of which is in contact with the outside of a mixer chamber, passes from the generator chamber to combine with the fresh feed fuel inlet at the entrance to the mixer chamber, and a mixer nozzle is located at the entrance to the mixer chamber, where the mixer chamber connects with the reforming chamber, and where the mixer-diffuser chamber and mixer nozzle are exterior to and spaced apart from the combustion chamber, and the generator chamber, and the mixer nozzle can operate below 400 C. 2 figs.

  6. Multiband terahertz quasi-optical balanced hot-electron mixers based on dual-polarization sinuous antennas

    NASA Astrophysics Data System (ADS)

    Jiang, Zhenguo; Rahman, Syed M.; Ruggiero, Steven T.; Fay, Patrick; Liu, Lei

    2014-05-01

    Receivers based on superconducting Hot-Electron Bolometers (HEBs) are widely used for terahertz (THz) sensing owing to their advantages of high sensitivity, low noise, and low LO power requirement. Balanced HEB mixers are superior to single-element ones since the thermal noise and AM noise from the LO injection can be effectively suppressed. Although a 1.3 THz balanced waveguide HEB mixer has been reported, waveguide mixer configurations offer relatively narrow RF bandwidths. We report on the development, fabrication and characterization of a THz quasioptical balanced superconducting HEB mixer utilizing a dual-polarization sinuous antenna that can potentially achieve both multiband operation and ultra-high sensitivity. In the balanced mixer configuration, a lens-coupled four-arm sinuous antenna was designed for operation from 0.2-1.0 THz with a nearly frequency-independent embedding impedance of ~106 Ω. Two identical superconducting niobium HEB devices have been integrated at the antenna feedpoints, connecting each opposing pair of antenna arms to form a balanced mixer configuration. An air-bridge was also fabricated to separate the two mixer branches. The HEB devices were fabricated from 10 nm thick niobium film sputtered on semi-insulating silicon substrates. Each HEB device has dimensions of 80 nm × 240 nm (3 squares) for approaching a resistance of 105 Ω for impedance matching. Mixer properties including antenna radiation patterns, broadband operation and polarization isolation have been characterized. Finally, in order to achieve multiband mixer operation, electronically reconfigurable THz quasi-optical mesh filters are needed. Frequency-tunable antenna elements using Schottky varactor diodes suitable for the above applications have been designed, simulated and demonstrated at Gband (140-220 GHz) showing 50 GHz tuning range.

  7. High-pressure liquid chromatographic gradient mixer

    DOEpatents

    Daughton, C.G.; Sakaji, R.H.

    1982-09-08

    A gradient mixer effects the continuous mixing of any two miscible solvents without excessive decay or dispersion of the resultant isocratic effluent or of a linear or exponential gradient. The two solvents are fed under low or high pressure by means of two high performance liquid chromatographic pumps. The mixer comprises a series of ultra-low dead volume stainless steel tubes and low dead volume chambers. The two solvent streams impinge head-on at high fluxes. This initial nonhomogeneous mixture is then passed through a chamber packed with spirally-wound wires which cause turbulent mixing thereby homogenizing the mixture with minimum band-broadening.

  8. High pressure liquid chromatographic gradient mixer

    DOEpatents

    Daughton, Christian G.; Sakaji, Richard H.

    1985-01-01

    A gradient mixer which effects the continuous mixing of any two miscible solvents without excessive decay or dispersion of the resultant isocratic effluent or of a linear or exponential gradient. The two solvents are fed under low or high pressure by means of two high performance liquid chromatographic pumps. The mixer comprises a series of ultra-low dead volume stainless steel tubes and low dead volume chambers. The two solvent streams impinge head-on at high fluxes. This initial nonhomogeneous mixture is then passed through a chamber packed with spirally-wound wires which cause turbulent mixing thereby homogenizing the mixture with minimum "band-broadening".

  9. Real World Projects in an Advanced Instructional Design Course

    ERIC Educational Resources Information Center

    Tracey, Monica W.; Chatervert, Lake, Kristy; Wilson, Robert

    2008-01-01

    This design case focuses on the redesign of Advanced Instructional Design, a capstone course taught in a Midwestern university's Masters of Training and Development program. The goal of the course was to have students integrate knowledge and skills from previous courses including needs assessment, introduction to instructional design, and program…

  10. Computational Design of Advanced Nuclear Fuels

    SciTech Connect

    Savrasov, Sergey; Kotliar, Gabriel; Haule, Kristjan

    2014-06-03

    The objective of the project was to develop a method for theoretical understanding of nuclear fuel materials whose physical and thermophysical properties can be predicted from first principles using a novel dynamical mean field method for electronic structure calculations. We concentrated our study on uranium, plutonium, their oxides, nitrides, carbides, as well as some rare earth materials whose 4f eletrons provide a simplified framework for understanding complex behavior of the f electrons. We addressed the issues connected to the electronic structure, lattice instabilities, phonon and magnon dynamics as well as thermal conductivity. This allowed us to evaluate characteristics of advanced nuclear fuel systems using computer based simulations and avoid costly experiments.

  11. Advanced solar concentrator: Preliminary and detailed design

    NASA Technical Reports Server (NTRS)

    Bell, D. M.; Maraschin, R. A.; Matsushita, M. T.; Erskine, D.; Carlton, R.; Jakovcevic, A.; Yasuda, A. K.

    1981-01-01

    A single reflection point focusing two-axis tracking paraboloidal dish with a reflector aperture diameter of approximately 11 m has a reflective surface made up of 64 independent, optical quality gores. Each gore is a composite of a thin backsilvered mirror glass face sheet continuously bonded to a contoured substrate of lightweight, rigid cellular glass. The use of largely self-supporting gores allows a significant reduction in the weight of the steel support structure as compared to alternate design concepts. Primary emphasis in the preliminary design package for the low-cost, low-weight, mass producible concentrator was placed on the design of the higher cost subsystems. The outer gore element was sufficiently designed to allow fabrication of prototype gores.

  12. Advanced nursing practice: old hat, new design.

    PubMed

    De Grasse, C; Nicklin, W

    2001-01-01

    Advanced practice nurses positively impact the delivery of healthcare and client outcomes. However, in the past these positions have been seen to have variable value and were often vulnerable during budget cuts. Lack of a clear advanced nursing practice (ANP) framework probably contributed to the compromised effectiveness of these roles and evolution of roles with different titles, scopes of practice and reporting structures. To build the foundation for developing an ANP framework, a task force at The Ottawa Hospital (TOH) conducted a literature review related to ANP roles and completed a review of all clinical nursing roles at TOH. In addition, focus groups with nurses and other health professionals elicited ANP perceptions. The ANP framework includes a standardized job description that details competencies under five role components: clinical practice; consultation; research; education; and, leadership. Recommendations for assessment, implementation and evaluation of ANP roles are identified. The process undertaken by our ANP task force proved to be thorough and sound in developing a framework within which to move forward with ANP role implementation throughout TOH. This article, describing the process, may assist other organizations in defining ANP roles to better meet patient needs in changing health care environments. PMID:11803945

  13. Gen 2.0 Mixer/Ejector Nozzle Test at LSAF June 1995 to July 1996

    NASA Technical Reports Server (NTRS)

    Arney, L. D.; Sandquist, D. L.; Forsyth, D. W.; Lidstone, G. L.; Long-Davis, Mary Jo (Technical Monitor)

    2005-01-01

    Testing of the HSCT Generation 2.0 nozzle model hardware was conducted at the Boeing Low Speed Aeroacoustic Facility, LSAF. Concurrent measurements of noise and thrust were made at critical takeoff design conditions for a variety of mixer/ejector model hardware. Design variables such as suppressor area ratio, mixer area ratio, liner type and thickness, ejector length, lobe penetration, and mixer chute shape were tested. Parallel testing was conducted at G.E.'s Cell 41 acoustic free jet facility to augment the LSAF test. The results from the Gen 2.0 testing are being used to help shape the current nozzle baseline configuration and guide the efforts in the upcoming Generation 2.5 and 3.0 nozzle tests. The Gen 2.0 results have been included in the total airplane system studies conducted at MDC and Boeing to provide updated noise and thrust performance estimates.

  14. Energy Efficient Engine exhaust mixer model technology report addendum; phase 3 test program

    NASA Technical Reports Server (NTRS)

    Larkin, M. J.; Blatt, J. R.

    1984-01-01

    The Phase 3 exhaust mixer test program was conducted to explore the trends established during previous Phases 1 and 2. Combinations of mixer design parameters were tested. Phase 3 testing showed that the best performance achievable within tailpipe length and diameter constraints is 2.55 percent better than an optimized separate flow base line. A reduced penetration design achieved about the same overall performance level at a substantially lower level of excess pressure loss but with a small reduction in mixing. To improve reliability of the data, the hot and cold flow thrust coefficient analysis used in Phases 1 and 2 was augmented by calculating percent mixing from traverse data. Relative change in percent mixing between configurations was determined from thrust and flow coefficient increments. The calculation procedure developed was found to be a useful tool in assessing mixer performance. Detailed flow field data were obtained to facilitate calibration of computer codes.

  15. Advanced Technology Display House. Volume 2: Energy system design concepts

    NASA Technical Reports Server (NTRS)

    Maund, D. H.

    1981-01-01

    The preliminary design concept for the energy systems in the Advanced Technology Display House is analyzed. Residential energy demand, energy conservation, and energy concepts are included. Photovoltaic arrays and REDOX (reduction oxidation) sizes are discussed.

  16. 21 CFR 868.5330 - Breathing gas mixer.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Breathing gas mixer. 868.5330 Section 868.5330...) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5330 Breathing gas mixer. (a) Identification. A breathing gas mixer is a device intended for use in conjunction with a respiratory...

  17. Mixer pump test plan for double shell tank AZ-101

    SciTech Connect

    STAEHR, T.W.

    1999-05-12

    Mixer pump systems have been chosen as the method for retrieval of tank wastes contained in double shell tanks at Hanford. This document describes the plan for testing and demonstrating the ability of two 300 hp mixer pumps to mobilize waste in tank AZ-101. The mixer pumps, equipment and instrumentation to monitor the test were installed by Project W-151.

  18. 21 CFR 888.4210 - Cement mixer for clinical use.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Cement mixer for clinical use. 888.4210 Section... (CONTINUED) MEDICAL DEVICES ORTHOPEDIC DEVICES Surgical Devices § 888.4210 Cement mixer for clinical use. (a) Identification. A cement mixer for clinical use is a device consisting of a container intended for use in...

  19. 21 CFR 888.4210 - Cement mixer for clinical use.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Cement mixer for clinical use. 888.4210 Section... (CONTINUED) MEDICAL DEVICES ORTHOPEDIC DEVICES Surgical Devices § 888.4210 Cement mixer for clinical use. (a) Identification. A cement mixer for clinical use is a device consisting of a container intended for use in...

  20. 21 CFR 888.4210 - Cement mixer for clinical use.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Cement mixer for clinical use. 888.4210 Section... (CONTINUED) MEDICAL DEVICES ORTHOPEDIC DEVICES Surgical Devices § 888.4210 Cement mixer for clinical use. (a) Identification. A cement mixer for clinical use is a device consisting of a container intended for use in...

  1. 21 CFR 888.4210 - Cement mixer for clinical use.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Cement mixer for clinical use. 888.4210 Section... (CONTINUED) MEDICAL DEVICES ORTHOPEDIC DEVICES Surgical Devices § 888.4210 Cement mixer for clinical use. (a) Identification. A cement mixer for clinical use is a device consisting of a container intended for use in...

  2. 21 CFR 888.4210 - Cement mixer for clinical use.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Cement mixer for clinical use. 888.4210 Section... (CONTINUED) MEDICAL DEVICES ORTHOPEDIC DEVICES Surgical Devices § 888.4210 Cement mixer for clinical use. (a) Identification. A cement mixer for clinical use is a device consisting of a container intended for use in...

  3. Submillimeter-Wave Receiver Containing An SIS Mixer

    NASA Technical Reports Server (NTRS)

    Febvre, Pascal; Mcgrath, William R.; Batelaan, Paul D.; Leduc, Henry G.; Bumble, Bruce; Frerking, Margaret A.; Hernichel, Juergen

    1996-01-01

    Submillimeter-wave heterodyne receiver designed to operate at input frequencies in range of 480 to 650 GHz. Intended for use in radio astronomy at frequency of 547 or 626 GHz. Heart of receiver is waveguide mixer that includes adjustable backshort and electric-field-plane tuner. Mixing element high-current-density superconductor/insulator/superconductor (SIS) tunnel junction integrated with superconductive microstrip radio-frequency circuit that tunes out capacitance of junction; matching complex impedance of junction to available tuning range of waveguide mount.

  4. Advanced High Temperature Reactor Neutronic Core Design

    SciTech Connect

    Ilas, Dan; Holcomb, David Eugene; Varma, Venugopal Koikal

    2012-01-01

    The AHTR is a 3400 MW(t) FHR class reactor design concept intended to serve as a central generating station type power plant. While significant technology development and demonstration remains, the basic design concept appears sound and tolerant of much of the remaining performance uncertainty. No fundamental impediments have been identified that would prevent widespread deployment of the concept. This paper focuses on the preliminary neutronic design studies performed at ORNL during the fiscal year 2011. After a brief presentation of the AHTR design concept, the paper summarizes several neutronic studies performed at ORNL during 2011. An optimization study for the AHTR core is first presented. The temperature and void coefficients of reactivity are then analyzed for a few configurations of interest. A discussion of the limiting factors due to the fast neutron fluence follows. The neutronic studies conclude with a discussion of the control and shutdown options. The studies presented confirm that sound neutronic alternatives exist for the design of the AHTR to maintain full passive safety features and reasonable operation conditions.

  5. Advanced airfoil design empirically based transonic aircraft drag buildup technique

    NASA Technical Reports Server (NTRS)

    Morrison, W. D., Jr.

    1976-01-01

    To systematically investigate the potential of advanced airfoils in advance preliminary design studies, empirical relationships were derived, based on available wind tunnel test data, through which total drag is determined recognizing all major aircraft geometric variables. This technique recognizes a single design lift coefficient and Mach number for each aircraft. Using this technique drag polars are derived for all Mach numbers up to MDesign + 0.05 and lift coefficients -0.40 to +0.20 from CLDesign.

  6. Advanced cell designs for welded arrays

    SciTech Connect

    Giuliano, M.; Wohlgemuth, J.

    1982-08-01

    In this paper the authors present some solar cell design innovations and associated process technology which can result in practical welded contacts for interconnection into arrays. The principal problem with welded contacts on solar cells relates to electrical and mechanical damage to the shallow diffused front junction of the cell. Design approaches are presented which result in a deeper pn junction under the weld contact point. This moves the location of the junction to a safer distance below the region of heat and pressure resulting from the welding operation. The methods presented can be used with various welding techniques including parallel gap welding, ultrasonic welding, laser spot welding or thermo-compression bonding. Design approaches include the development of a eutectic bonding technique to provide weldable contacts on front and back of the solar cell, as well as a novel integral feedthrough approach which permits welding of both contacts on the back of the cell.

  7. Advanced ERS design using computer simulation

    SciTech Connect

    Melhem, G.A.

    1995-12-31

    There are two schools of thought regarding pressure relief design, shortcut/simplified methods and detailed methods. The shortcut/simplified methods are mostly applicable to non-reactive systems. These methods use direct scale-up techniques to obtain a vent size. Little useful information can be obtained for reaction data such as onset temperatures, activation energy, decompositon stoichiometry, etc. In addition, this approach does not readily provide the ability to perform what-if and sensitivity analysis or data that can be used for post-release mitigation design. The detailed approach advocates a more fundamental approach to pressure relief design, especially for reactive systems. First, the reaction chemistry is qualified using small scale experiments and then this data is coupled with fluid dynamics to design the emergency relief system. In addition to vent sizing information, this approach provides insights into process modification and refinement as well as the establishment of a safe operating envelope. This approach provides necessary flow data for vent containment design (if required), structural support, etc. This approach also allows the direct evaluation of design sensitivity to variables such as temperature, pressure, composition, fill level, etc. on vent sizing while the shortcut approach requires an additional experiment per what-if scenario. This approach meets DIERS technology requirements for two-phase flow and vapor/liquid disengagement and exceeds it in many key areas for reacting systems such as stoichiometry estimation for decomposition reactions, non-ideal solutions effects, continuing reactions in piping and vent containment systems, etc. This paper provides an overview of our proposed equation of state based modeling approach and its computer code implementation. Numerous examples and model validations are also described. 42 refs., 23 figs., 9 tabs.

  8. A Planar Microfluidic Mixer Based on Logarithmic Spirals

    PubMed Central

    Scherr, Thomas; Quitadamo, Christian; Tesvich, Preston; Park, Daniel Sang-Won; Tiersch, Terrence; Hayes, Daniel; Choi, Jin-Woo; Nandakumar, Krishnaswamy

    2013-01-01

    A passive, planar micromixer design based on logarithmic spirals is presented. The device was fabricated using polydimethylsiloxane soft photolithography techniques, and mixing performance was characterized via numerical simulation and fluorescent microscopy. Mixing efficiency initially declined as Reynolds number increased, and this trend continued until a Reynolds number of 15 where a minimum was reached at 53%. Mixing efficiency then began to increase reaching a maximum mixing efficiency of 86% at Re = 67. Three-dimensional simulations of fluid mixing in this design were compared to other planar geometries such as the Archimedes spiral and Meandering-S mixers. The implementation of logarithmic curvature offers several unique advantages that enhance mixing, namely a variable cross-sectional area and a logarithmically varying radius of curvature that creates 3-D Dean vortices. These flow phenomena were observed in simulations with multilayered fluid folding and validated with confocal microscopy. This design provides improved mixing performance over a broader range of Reynolds numbers than other reported planar mixers, all while avoiding external force fields, more complicated fabrication processes, and the introduction of flow obstructions or cavities that may unintentionally affect sensitive or particulate-containing samples. Due to the planar design requiring only single-step lithographic features, this compact geometry could be easily implemented into existing micro-total analysis systems requiring effective rapid mixing. PMID:23956497

  9. Reconfigurable Advanced Receiver Design and Implementation

    NASA Technical Reports Server (NTRS)

    Xu, Jianjing

    2005-01-01

    While the demand for real-time broadband information access has grown and continues to grow at a rapid Pace, the need for a reconfigurable receiver system has increased. To achieve the goal to communicate with multiple shuttles at a time, a filter bank in polyphase structure is introduced. This paper presents the design and implementation for high-speed, high-performance, and fixed-point polyphase filter banks. The polyphase filter structure is designed such that the use of a fixed-point system has minimum impact on the performance of the filter. The final hardware implementation is done on a Xilinx FPGA chip.

  10. Submillimeter SIS Mixers Using High Current Density Nb/AIN/Nb Tunnel Junctions and NbTiN Films

    NASA Astrophysics Data System (ADS)

    Kawamura, J.; Miller, D.; Chen, J.; Kooi, J.; Zmuidzinas, J.; Bumble, B.; Leduc, H.; Stern, J.

    1999-03-01

    We are currently exploring ways to improve the performance of SIS mixers above 700 GHz. One approach is to use NbTiN in place of Nb for all or some of the mixer circuitry. With its high gap frequency and low losses demonstrated up to 800 GHz, it should be possible to fabricate an all-NbTiN SIS mixer with near quantum-limited noise performance up to 1.2 THz. Using a quasioptical twin-slot two-junction mixer with NbTiN ground plane and wiring and hybrid Nb/A1N/NbTiN junctions, we measured an uncorrected receiver noise temperature of TRx ~ 500 K across 790-850 GHz at 4.2 K bath temperature. Our second approach is to reduce the RC product of the mixer by employing very high current density Nb/A1N/Nb junctions. By using these we will greatly relax the requirement on tuning circuits, which is where substantial losses occur in mixers operating above the Nb gap frequency. These junctions have resistance-area products of R_N*A ~ 5.6 Ohm um2, good subgap to normal resistance ratios, R_sg/R_N ~ 10, and good run-to-run reproducibility. From FTS measurements we infer that omega*R_N*C = 1 at 270 GHz in these junctions. This is a substantial improvement over that available using Nb/Al0x/Nb technology. The sensitivity of a receiver incorporating these high current density mixers is T_Rx = 110 K at 533 GHz using a design for lower J_c mixers, which is close to the best we have measured with lower J_c Nb/Al0x/Nb mixers.

  11. Advances in electrometer vacuum tube design

    NASA Technical Reports Server (NTRS)

    1970-01-01

    Single-ended, miniature-cathode tube with a relatively low grid current level is constructed. Adequate cathode temperature at relatively low heater power drain is provided by designing the supporting spacers to provide a square cathode hole. Method of assembling the mount and bonding the elements is discussed.

  12. Reciprocating flow-based centrifugal microfluidics mixer

    NASA Astrophysics Data System (ADS)

    Noroozi, Zahra; Kido, Horacio; Micic, Miodrag; Pan, Hansheng; Bartolome, Christian; Princevac, Marko; Zoval, Jim; Madou, Marc

    2009-07-01

    Proper mixing of reagents is of paramount importance for an efficient chemical reaction. While on a large scale there are many good solutions for quantitative mixing of reagents, as of today, efficient and inexpensive fluid mixing in the nanoliter and microliter volume range is still a challenge. Complete, i.e., quantitative mixing is of special importance in any small-scale analytical application because the scarcity of analytes and the low volume of the reagents demand efficient utilization of all available reaction components. In this paper we demonstrate the design and fabrication of a novel centrifugal force-based unit for fast mixing of fluids in the nanoliter to microliter volume range. The device consists of a number of chambers (including two loading chambers, one pressure chamber, and one mixing chamber) that are connected through a network of microchannels, and is made by bonding a slab of polydimethylsiloxane (PDMS) to a glass slide. The PDMS slab was cast using a SU-8 master mold fabricated by a two-level photolithography process. This microfluidic mixer exploits centrifugal force and pneumatic pressure to reciprocate the flow of fluid samples in order to minimize the amount of sample and the time of mixing. The process of mixing was monitored by utilizing the planar laser induced fluorescence (PLIF) technique. A time series of high resolution images of the mixing chamber were analyzed for the spatial distribution of light intensities as the two fluids (suspension of red fluorescent particles and water) mixed. Histograms of the fluorescent emissions within the mixing chamber during different stages of the mixing process were created to quantify the level of mixing of the mixing fluids. The results suggest that quantitative mixing was achieved in less than 3 min. This device can be employed as a stand alone mixing unit or may be integrated into a disk-based microfluidic system where, in addition to mixing, several other sample preparation steps may be

  13. Quasi-Optical SIS Mixer Development

    NASA Technical Reports Server (NTRS)

    Zmuidzinas, J.

    1997-01-01

    This grant supported our ongoing development of sensitive quasi-optical SIS mixers for the submillimeter band. The technology developed under this grant is now being applied to NASA missions, including the NASA/USRA SOFIA airborne observatory and and the ESA/NASA FIRST/Herschel space astronomy mission.

  14. Parachute systems technology: Fundamentals, concepts, and applications: Advanced parachute design

    SciTech Connect

    Peterson, C.W.; Johnson, D.W.

    1987-01-01

    Advances in high-performance parachute systems and the technologies needed to design them are presented in this paper. New parachute design and performance prediction codes are being developed to assist the designer in meeting parachute system performance requirements after a minimum number of flight tests. The status of advanced design codes under development at Sandia National Laboratories is summarized. An integral part of parachute performance prediction is the rational use of existing test data. The development of a data base for parachute design has been initiated to illustrate the effects of inflated diameter, geometric porosity, reefing line length, suspension line length, number of gores, and number of ribbons on parachute drag. Examples of advancements in parachute materials are presented, and recent problems with Mil-Spec broadgoods are reviewed. Finally, recent parachute systems tested at Sandia are summarized to illustrate new uses of old parachutes, new parachute configurations, and underwater recovery of payloads.

  15. Submillisecond mixing in a continuous-flow, microfluidic mixer utilizing mid-infrared hyperspectral imaging detection

    PubMed Central

    Kise, Drew P.; Magana, Donny; Reddish, Michael J.

    2014-01-01

    We report a continuous-flow, microfluidic mixer utilizing mid-infrared hyperspectral imaging detection, with an experimentally determined, submillisecond mixing time. The simple and robust mixer design has the microfluidic channels cut through a polymer spacer that is sandwiched between two IR transparent windows. The mixer hydrodynamically focuses the sample stream with two side flow channels, squeezing it into a thin jet and initiating mixing through diffusion and advection. The detection system generates a mid-infrared hyperspectral absorbance image of the microfluidic sample stream. Calibration of the hyperspectral image yields the mid-IR absorbance spectrum of the sample versus time. A mixing time of 269 μs was measured for a pD jump from 3.2 to above 4.5 in a D2O sample solution of adenosine monophosphate (AMP), which acts as an infrared pD indicator. The mixer was further characterized by comparing experimental results with a simulation of the mixing of an H2O sample stream with a D2O sheath flow, showing good agreement between the two. The IR microfluidic mixer eliminates the need for fluorescence labeling of proteins with bulky, interfering dyes, because it uses the intrinsic IR absorbance of the molecules of interest, and the structural specificity of IR spectroscopy to follow specific chemical changes such as the protonation state of AMP. PMID:24302515

  16. Recent advances in NADH electrochemical sensing design.

    PubMed

    Radoi, Antonio; Compagnone, Dario

    2009-09-01

    NADH electrochemical sensor development has been one of the most studied areas of bioelectroanalysis because of the ubiquity of NAD(P)H based enzymatic reactions in nature. The different solutions proposed are still far from the realisation of the "ideal" NADH sensor and the research area is still challenging. The principles and the recent approaches in NADH electrochemical sensing design are reported in this review. An overview of selected examples and novel sensor materials for the electrocatalysis of NADH is given with emphasis on the appropriate design to obtain improved performances. The literature data taken in consideration has been grouped depending on the strategy used in: surface modified electrodes for NADH sensing, surface redox mediated NADH probes, and bulk modified electrodes for the electrocatalytic oxidation of NADH. A list of already reported dehydrogenase-based biosensors is also given. PMID:19608463

  17. Radiation design considerations for advanced Jupiter spacecraft

    NASA Technical Reports Server (NTRS)

    Bouquet, F. L.; Koprowski, E. F.

    1979-01-01

    This paper considers one aspect of the complex radiation design considerations for planetary spacecraft, namely the approach used for solving the effects of radiation on materials problems. An overview of the approach developed at JPL for Voyager, and currently being used on Galileo, is treated briefly. Examples of the postulated Jovian charged particle levels are given. The types of computer analyses codes used, the mass shielding techniques that evolved and the recommended shielding techniques for future planetary spacecraft are treated.

  18. Advanced designs for fluid flow visualization

    NASA Technical Reports Server (NTRS)

    1978-01-01

    Research was carried out on existing and new designs for minimally intrusive measurement of flow fields in the Geophysical Fluid Flow Cell and the proposed Atmospheric General Circulation Experiment. The following topics are discussed: (1) identification and removal of foreign particles, (2) search for higher dielectric photochromic solutions, (3) selection of uv light source, (4) analysis of refractive techniques and (5) examination of fresnel lens applicability.

  19. Oxide_Oxide Ceramic Matrix Composite (CMC) Exhaust Mixer Development in the NASA Environmentally Responsible Aviation (ERA) Project

    NASA Technical Reports Server (NTRS)

    Kiser, James D.; Bansal, Narottam P.; Szelagowski, J.; Sokhey, J.; Heffernan, T.; Clegg, J.; Pierluissi, A.; Riedell, J.; Atmur, S.; Wyen, T.; Ursic, J.

    2015-01-01

    Rolls-Royce North American Technologies, Inc. (LibertyWorksLW) began considering the development of CMC exhaust forced mixers in 2008, as a means of obtaining reduced weight and hotter operating temperature capability, while minimizing shape distortion during operation, which would improve mixing efficiency and reduce fuel burn. Increased component durability, enhanced ability to fabricate complex-shaped components, and engine noise reduction are other potential advantages of CMC mixers (compared to metallic mixers). In 2010, NASA was pursuing the reduction of NOx emissions, fuel burn, and noise from turbine engines in Phase I of the Environmentally Responsible Aviation (ERA) Project. ERA subtasks, including those focused on CMC components, were formulated with the goal of maturing technology from proof of concept validation (TRL 3) to a systemsubsystem or prototype demonstration in a relevant environment (TRL 6). In April 2010, the NASA Glenn Research Center (GRC) and LibertyWorks jointly initiated a CMC Exhaust System Validation Program within the ERA Project, teaming on CMC exhaust mixer development for subsonic jet engines capable of operating with increased performance. Our initial focus was on designing, fabricating, and characterizing the thrust and acoustic performance of a roughly quarter-scale 16-lobe oxide oxide CMC mixer and tail cone along with a conventional low bypass exhaust nozzle. Support Services, LLC (Allendale, MI) and ATK COI Ceramics, Inc. (COIC, in San Diego, CA) supported the design of a subscale nozzle assembly that consisted of an oxide oxide CMC mixer and center body, with each component mounted on a metallic attachment ring. That design was based upon the operating conditions a mixer would experience in a turbofan engine. Validation of the aerodynamic and acoustic performance of the subscale mixer via testing and the achievement of TRL 4 encouraged the NASALWCOIC team to move to the next phase where a full scale CMC mixer sized for a RR

  20. Advanced EVA system design requirements study

    NASA Technical Reports Server (NTRS)

    Woods, T. G.

    1988-01-01

    The results are presented of a study to identify specific criteria regarding space station extravehicular activity system (EVAS) hardware requirements. Key EVA design issues include maintainability, technology readiness, LSS volume vs. EVA time available, suit pressure/cabin pressure relationship and productivity effects, crew autonomy, integration of EVA as a program resource, and standardization of task interfaces. A variety of DOD EVA systems issues were taken into consideration. Recommendations include: (1) crew limitations, not hardware limitations; (2) capability to perform all of 15 generic missions; (3) 90 days on-orbit maintainability with 50 percent duty cycle as minimum; and (4) use by payload sponsors of JSC document 10615A plus a Generic Tool Kit and Specialized Tool Kit description. EVA baseline design requirements and criteria, including requirements of various subsystems, are outlined. Space station/EVA system interface requirements and EVA accommodations are discussed in the areas of atmosphere composition and pressure, communications, data management, logistics, safe haven, SS exterior and interior requirements, and SS airlock.

  1. Noise performance of phase-insensitive frequency multicasting in parametric mixer with finite dispersion.

    PubMed

    Tong, Zhi; Wiberg, Andreas O J; Myslivets, Evgeny; Huynh, Chris K; Kuo, Bill P P; Alic, Nikola; Radic, Stojan

    2013-07-29

    Noise performance of dual-pump, multi-sideband parametric mixer operated in phase-insensitive mode is investigated theoretically and experimentally. It is shown that, in case when a large number of multicasting idlers are generated, the noise performance is strictly dictated by the dispersion characteristics of the mixer. We find that the sideband noise performance is significantly degraded in anomalous dispersion region permitting nonlinear noise amplification. In contrast, in normal dispersion region, the noise performance converges to the level of four-sideband parametric process, rather than deteriorates with increased sideband creation. Low noise generation mandates precise dispersion-induced phase mismatch among pump and sideband waves in order to control the noise coupling. We measure the noise performance improvement for a many-sideband, multi-stage mixer by incorporating new design technique. PMID:23938638

  2. Superconductive hot-electron-bolometer mixer receiver for 800-GHz operation

    NASA Astrophysics Data System (ADS)

    Kawamura, J.; Blundell, R.; Tong, C.-Y. E.; Papa, D. C.; Hunter, T. R.; Paine, S. N.; Patt, F.; Gol'Tsman, G.; Cherednichenko, S.; Voronov, B.; Gershenzon, E.

    2000-04-01

    In this paper, we describe a superconductive hot-electron-bolometer mixer receiver designed to operate in the partially transmissive 350-μm atmospheric window. The receiver employs an NbN thin-film microbridge as the mixer element, in which the main cooling mechanism of the hot electrons is through electron-phonon interaction. At a local-oscillator frequency of 808 GHz, the measured double-sideband receiver noise temperature is Trx=970 K, across a 1-GHz intermediate-frequency bandwidth centered at 1.8 GHz. We have measured the linearity of the receiver and the amount of local-oscillator power incident on the mixer for optimal operation, which is PLO ≈ 1 microwatt. This receiver was used in making observations as a facility instrument at the Heinrich Hertz Telescope, Mt. Graham, AZ, during the 1998-1999 winter observing season.

  3. TMF design considerations in turbine airfoils of advanced turbine engines

    NASA Astrophysics Data System (ADS)

    Date, C. G.; Zamrik, S. Y.; Adams, J. H.; Frani, N. E.

    A review of thermal-mechanicalfatigue (TMF) in advanced turbine engines is presented. The review includes examples of typical thermal-mechnical loadings encountered in the design of hot section blades and vanes. Specific issues related to TMF behavior are presented and the associated impact on component life analysis and design is discussed.

  4. Design, analysis and test verification of advanced encapsulation systems

    NASA Technical Reports Server (NTRS)

    Garcia, A., III

    1983-01-01

    The analytical methodology for advanced encapsulation designs for the development of photovoltaic modules is presented. Analytical models are developed to test optical, thermal, electrical and structural properties of the various encapsulation systems. Model data is compared to relevant test data to improve model accuracy and develop general principles for the design of photovoltaic modules.

  5. BASELINE DESIGN/ECONOMICS FOR ADVANCED FISCHER-TROPSCH TECHNOLOGY

    SciTech Connect

    1998-04-01

    Bechtel, along with Amoco as the main subcontractor, developed a Baseline design, two alternative designs, and computer process simulation models for indirect coal liquefaction based on advanced Fischer-Tropsch (F-T) technology for the U. S. Department of Energy's (DOE's) Federal Energy Technology Center (FETC).

  6. A User's Guide for the Differential Reduced Ejector/Mixer Analysis "DREA" Program. 1.0

    NASA Technical Reports Server (NTRS)

    DeChant, Lawrence J.; Nadell, Shari-Beth

    1999-01-01

    A system of analytical and numerical two-dimensional mixer/ejector nozzle models that require minimal empirical input has been developed and programmed for use in conceptual and preliminary design. This report contains a user's guide describing the operation of the computer code, DREA (Differential Reduced Ejector/mixer Analysis), that contains these mathematical models. This program is currently being adopted by the Propulsion Systems Analysis Office at the NASA Glenn Research Center. A brief summary of the DREA method is provided, followed by detailed descriptions of the program input and output files. Sample cases demonstrating the application of the program are presented.

  7. Design considerations for advanced battery concepts

    NASA Technical Reports Server (NTRS)

    Leibecki, H. F.; Thaller, L. H.

    1986-01-01

    A mathematical representation for the charge and discharge of a sodium-sulfur cell is developed. These equations are then used as the basis for a computerized model to examine the effects of cell arrangement in the design of a large multi-kilowatt battery from a group of hypothetical individual cells with known variations in their ampere hour capacity and internal resistance. The cycling characteristics of 216 individual cells arranged in six different configurations are evaluated with the view towards minimizing the adverse effects that are introduced due to the stoichastic aspects of groupings of cells, as well as the possibility of cell failures in both the open and shorted mode. Although battery systems based on sodium-sulfur cells are described in this example, any of the newer electrochemical systems can be fitted into this framework by making appropriate modifications to the basic equations.

  8. Advancements in ion diode and triode design.

    PubMed

    Cavenago, M

    2014-02-01

    Selfconsistent laminar flow models, which enable to predict the optimal cathode and anode geometry in simple diodes, must be modified to account for the anode aperture and the effect of other electrodes. An equation for charge coupled to arbitrary laminar flows is here first presented and its numerical solutions are obtained with a new method, based on mesh transformations. It is found that a close match to theoretical flows requires an increase of the simple diode voltage v0 by an amount vδ, which, for a typical case designed for zero exit angle condition, are v0 = 0.7465 and vδ = 0.0294 in adimensional units. States "in" and "out" for the anode lens are also shown, where "out" is a new and nonlinear solution for the beam expansion in a drift tube. PMID:24593456

  9. Advancements in ion diode and triode design

    NASA Astrophysics Data System (ADS)

    Cavenago, M.

    2014-02-01

    Selfconsistent laminar flow models, which enable to predict the optimal cathode and anode geometry in simple diodes, must be modified to account for the anode aperture and the effect of other electrodes. An equation for charge coupled to arbitrary laminar flows is here first presented and its numerical solutions are obtained with a new method, based on mesh transformations. It is found that a close match to theoretical flows requires an increase of the simple diode voltage v0 by an amount vδ, which, for a typical case designed for zero exit angle condition, are v0 = 0.7465 and vδ = 0.0294 in adimensional units. States "in" and "out" for the anode lens are also shown, where "out" is a new and nonlinear solution for the beam expansion in a drift tube.

  10. Systems design of advanced gear steels

    NASA Astrophysics Data System (ADS)

    Wise, John Patrick

    A new generation of Ni-Co secondary hardening gear steels has been developed using a systems approach. These high toughness ultrahigh-strength martensitic steels show great promise for demanding gear applications. Quantitative science-based modeling was used to create prototype alloys of superior strength and fatigue resistance over conventional steels. Carburizing and strengthening models were developed to relate processing parameters to microstructure and microstructure to strength. The failure of the DICTRA software to accurately predict the carburizing behavior of Ni-Co steels led to a series of experiments to refine its kinetic database. New carbon diffusivities were calculated from the concentration gradients of carburized model alloys, resulting in a significant improvement of simulation accuracy. A structure/property model was created to equate the strength of a secondary hardening steel to the sum of the effects of solid solution, precipitates, dislocation density, and the substructure of the lath martensite matrix. The strengthening model was subsequently combined with the carburizing simulations to predict the hardness gradient in a case-hardened alloy based upon initial carburizing conditions. In addition, existing precipitation theory was used in conjunction with the microstructure/strength relationship to simulate the evolution of material hardness during secondary hardening. The creation of three prototype gear steels began with the use of the strengthening model to establish the carbon and alloying element contents required to reach the core and case hardness objectives of 50 and 70 HRC respectively. The design approach also included the establishment of proper transformation and solution temperatures and the maximization of the efficiency of the Msb2C carbide strengthening dispersion. The core hardnesses of the C3-A and B prototypes significantly exceeded the design goal. A reduction in core carbon content from 0.16 to 0.12 weight percent was

  11. CFD analyses for advanced pump design

    NASA Technical Reports Server (NTRS)

    Dejong, F. J.; Choi, S.-K.; Govindan, T. R.

    1994-01-01

    As one of the activities of the NASA/MSFC Pump Stage Technology Team, the present effort was focused on using CFD in the design and analysis of high performance rocket engine pumps. Under this effort, a three-dimensional Navier-Stokes code was used for various inducer and impeller flow field calculations. An existing algebraic grid generation procedure was-extended to allow for nonzero blade thickness, splitter blades, and hub/shroud cavities upstream or downstream of the (main) blades. This resulted in a fast, robust inducer/impeller geometry/grid generation package. Problems associated with running a compressible flow code to simulate an incompressible flow were resolved; related aspects of the numerical algorithm (viz., the matrix preconditioning, the artificial dissipation, and the treatment of low Mach number flows) were addressed. As shown by the calculations performed under the present effort, the resulting code, in conjunction with the grid generation package, is an effective tool for the rapid solution of three-dimensional viscous inducer and impeller flows.

  12. Assessment of the relative performance of a confined impinging jets mixer and a multi-inlet vortex mixer for curcumin nanoparticle production.

    PubMed

    Chow, Shing Fung; Sun, Changquan Calvin; Chow, Albert Hee Lum

    2014-10-01

    The relative performance of two specially designed mixers for nanoparticle production, namely, two-stream confined impinging jets with dilution mixer (CIJ-D-M) and four-stream multi-inlet vortex mixer (MIVM), was evaluated using the model compound, curcumin (CUR), under defined conditions of varying mixing rate and organic solvent. In the absence of turbulent fluctuations, higher mixing rate tended to generate finer particles. Among the three water-miscible organic solvents tested, acetone afforded the smallest particle size and the narrowest particle size distribution. Both mixers were capable of reproducibly fabricating CUR nanoparticles with particle size below 100 nm and high encapsulation efficiency (>99.9%). Specifically, CIJ-D-M yielded nanoparticles with smaller size and polydispersity index while the particles obtained by the MIVM displayed better short-term stability. In addition, CIJ-D-M tended to produce a mixture of irregular nanoaggregates and primary nanoparticles while roughly spherical nanoparticles were generated with the MIVM. The observed particle size and morphological differences could be attributed to the differences in the configuration of the mixing chamber and the related mixing order. PMID:25016977

  13. Advanced ROICs design for cooled IR detectors

    NASA Astrophysics Data System (ADS)

    Zécri, Michel; Maillart, Patrick; Sanson, Eric; Decaens, Gilbert; Lefoul, Xavier; Baud, Laurent

    2008-04-01

    The CMOS silicon focal plan array technologies hybridized with infrared detectors materials allow to cover a wide range of applications in the field of space, airborne and grounded-based imaging. Regarding other industries which are also using embedded systems, the requirements of such sensor assembly can be seen as very similar; high reliability, low weight, low power, radiation hardness for space applications and cost reduction. Comparing to CCDs technology, excepted the fact that CMOS fabrication uses standard commercial semiconductor foundry, the interest of this technology used in cooled IR sensors is its capability to operate in a wide range of temperature from 300K to cryogenic with a high density of integration and keeping at the same time good performances in term of frequency, noise and power consumption. The CMOS technology roadmap predict aggressive scaling down of device size, transistor threshold voltage, oxide and metal thicknesses to meet the growing demands for higher levels of integration and performance. At the same time infrared detectors manufacturing process is developing IR materials with a tunable cut-off wavelength capable to cover bandwidths from visible to 20μm. The requirements of third generation IR detectors are driving to scaling down the pixel pitch, to develop IR materials with high uniformity on larger formats, to develop Avalanche Photo Diodes (APD) and dual band technologies. These needs in IR detectors technologies developments associated to CMOS technology, used as a readout element, are offering new capabilities and new opportunities for cooled infrared FPAs. The exponential increase of new functionalities on chip, like the active 2D and 3D imaging, the on chip analog to digital conversion, the signal processing on chip, the bicolor, the dual band and DTI (Double Time Integration) mode ...is aiming to enlarge the field of application for cooled IR FPAs challenging by the way the design activity.

  14. SP-100 advanced radiator designs for thermoelectric and Stirling applications

    NASA Technical Reports Server (NTRS)

    Moriarty, M. P.; Determan, W. R.

    1989-01-01

    Advanced radiator designs employing carbon-carbon liquid metal heat pipe technology, which significantly reduce the mass of the heat rejection subsystem for high temperature space technology systems such as the SP-100 are discussed. This technology is being developed to address the need for lightweight heat transfer components and structures for space applications. Heat pipe and subsystem designs were optimized for thermoelectric- and Stirling-engine-based SP-100 system designs. A multiple, deployed-petal radiator concept was selected for the heat rejection subsystem design as it provided minimum mass. Radiator stowage in the space transportation system cargo bay and deployment schemes were investigated for each of the optimized designs.

  15. Preliminary design studies of an advanced general aviation aircraft

    NASA Technical Reports Server (NTRS)

    Barrett, Ron; Demoss, Shane; Dirkzwager, AB; Evans, Darryl; Gomer, Charles; Keiter, Jerry; Knipp, Darren; Seier, Glen; Smith, Steve; Wenninger, ED

    1991-01-01

    The preliminary design results are presented of the advanced aircraft design project. The goal was to take a revolutionary look into the design of a general aviation aircraft. Phase 1 of the project included the preliminary design of two configurations, a pusher, and a tractor. Phase 2 included the selection of only one configuration for further study. The pusher configuration was selected on the basis of performance characteristics, cabin noise, natural laminar flow, and system layouts. The design was then iterated to achieve higher levels of performance.

  16. Synthetic biology: advancing the design of diverse genetic systems

    PubMed Central

    Wang, Yen-Hsiang; Wei, Kathy Y.; Smolke, Christina D.

    2013-01-01

    A main objective of synthetic biology is to make the process of designing genetically-encoded biological systems more systematic, predictable, robust, scalable, and efficient. The examples of genetic systems in the field vary widely in terms of operating hosts, compositional approaches, and network complexity, ranging from a simple genetic switch to search-and-destroy systems. While significant advances in synthesis capabilities support the potential for the implementation of pathway- and genome-scale programs, several design challenges currently restrict the scale of systems that can be reasonably designed and implemented. Synthetic biology offers much promise in developing systems to address challenges faced in manufacturing, the environment and sustainability, and health and medicine, but the realization of this potential is currently limited by the diversity of available parts and effective design frameworks. As researchers make progress in bridging this design gap, advances in the field hint at ever more diverse applications for biological systems. PMID:23413816

  17. An Integrated 520-600 GHz Sub-Harmonic Mixer and Tripler Combination Based on GaAs MMIC Membrane Planar Schottky Diodes

    NASA Technical Reports Server (NTRS)

    Thomas, B.; Gill, J.; Maestrini, A.; Lee, C.; Lin, R.; Sin, S.; Peralta, A.; Mehdi, I.

    2010-01-01

    We present here the design, development and test of an integrated sub-millimeter front-end featuring a 520-600 GHz sub-harmonic mixer and a 260-300 GHz frequency tripler in a single cavity. Both devices used GaAs MMIC membrane planar Schottky diode technology. The sub-harmonic mixer/tripler circuit has been tested using conventional machined as well as silicon micro-machined blocks. Measurement results on the metal block give best DSB mixer noise temperature of 2360 K and conversion losses of 7.7 dB at 520 GHz. Preliminary results on the silicon micro-machined blocks give a DSB mixer noise temperature of 4860 K and conversion losses of 12.16 dB at 540 GHz. The LO input power required to pump the integrated tripler/sub-harmonic mixer for both packages is between 30 and 50 mW.

  18. An Integrated 520-600 GHz Sub-Harmonic Mixer and Tripler Combination Based on GaAs MMIC Membrane Planar Schottky Diodes

    NASA Technical Reports Server (NTRS)

    Thomas, B.; Gill, J.; Maestrini, A.; Lee, C.; Lin, R.; Sin, S.; Peralta, A.; Mehdi, I.

    2011-01-01

    We present here the design, development and test of an integrated sub-millimeter front-end featuring a 520-600 GHz sub-harmonic mixer and a 260-300 GHz frequency tripler in a single cavity. Both devices used GaAs MMIC membrane planar Schottky diode technology. The sub-harmonic mixer/tripler circuit has been tested using conventional machined as well as silicon micro-machined blocks. Measurement results on the metal block give best DSB mixer noise temperature of 2360 K and conversion losses of 7.7 dB at 520 GHz. Preliminary results on the silicon micro-machined blocks give a DSB mixer noise temperature of 4860 K and conversion losses of 12.16 dB at 540 GHz. The LO input power required to pump the integrated tripler/sub-harmonic mixer for both packages is between 30 and 50 mW

  19. Study on installation of the submersible mixer

    NASA Astrophysics Data System (ADS)

    Tian, F.; Shi, W. D.; He, X. H.; Jiang, H.; Xu, Y. H.

    2013-12-01

    Study on installation of the submersible mixer for sewage treatment has been limited. In this article, large-scale computational fluid dynamics software FLUENT6.3 was adopted. ICEM software was used to build an unstructured grid of sewage treatment pool. After that, the sewage treatment pool was numerically simulated by dynamic coordinate system technology and RNG k-ε turbulent model and PIOS algorithm. Agitation pools on four different installation location cases were simulated respectively, and the external characteristic of the submersible mixer and the velocity cloud of the axial section were respectively comparatively analyzed. The best stirring effect can be reached by the installation location of case C, which is near the bottom of the pool 600 mm and blade distance the bottom at least for 200 mm wide and wide edge and narrow edge distance by 4:3. The conclusion can guide the engineering practice.

  20. Development of SIS Mixers for 1 THz

    NASA Technical Reports Server (NTRS)

    Zmuidzinas, J.; Kooi, J.; Chattopadhyay, G.; Bumble, B.; LeDuc, H. G.; Stern, J. A.

    1998-01-01

    SIS heterodyne mixer technology based on niobium tunnel junctions has now been pushed to frequencies over 1 THz, clearly demonstrating that the SIS junctions are capable of mixing at frequencies up to twice the energy gap frequency (4 Delta/h). However, the performance degrades rapidly above the gap frequency of niobium (2 Delta/h approx. 700 GHz) due to substantial ohmic losses in the on-chip tuning circuit. To solve this problem, the tuning circuit should be fabricated using a superconducting film with a larger energy gap, such as NbN; unfortunately, NbN films often have a substantial excess surface resistance in the submillimeter band. In contrast, the SIS mixer measurements we present in this paper indicate that the losses for NbTiN thin films can be quite low.

  1. ADVANCED TURBINE SYSTEM CONCEPTUAL DESIGN AND PRODUCT DEVELOPMENT - Final Report

    SciTech Connect

    Albrecht H. Mayer

    2000-07-15

    Asea Brown Boveri (ABB) has completed its technology based program. The results developed under Work Breakdown Structure (WBS) 8, concentrated on technology development and demonstration have been partially implemented in newer turbine designs. A significant improvement in heat rate and power output has been demonstrated. ABB will use the knowledge gained to further improve the efficiency of its Advanced Cycle System, which has been developed and introduced into the marked out side ABB's Advanced Turbine System (ATS) activities. The technology will lead to a power plant design that meets the ATS performance goals of over 60% plant efficiency, decreased electricity costs to consumers and lowest emissions.

  2. WRAP 2A advanced conceptual design report comments

    SciTech Connect

    Lamberd, D.L.

    1994-10-04

    This report contains the compilation of the 393 comments that were submitted during the review of the Advanced Conceptual Design Report for the Waste Receiving and Processing Facility Module 2A. The report was prepared by Raytheon Engineers and Constructors, Inc. of Englewood, Colorado for the United States Department of Energy. The review was performed by a variety of organizations identified in the report. The comments were addressed first by the Westinghouse cognizant engineers and then by the Raytheon cognizant engineers, and incorporated into the final issue of the Advanced Conceptual Design Report.

  3. Directed molecular evolution to design advanced red fluorescent proteins

    PubMed Central

    Subach, Fedor V; Piatkevich, Kiryl D; Verkhusha, Vladislav V

    2015-01-01

    Fluorescent proteins have become indispensable imaging tools for biomedical research. continuing progress in fluorescence imaging, however, requires probes with additional colors and properties optimized for emerging techniques. Here we summarize strategies for development of red-shifted fluorescent proteins. We discuss possibilities for knowledge-based rational design based on the photochemistry of fluorescent proteins and the position of the chromophore in protein structure. We consider advances in library design by mutagenesis, protein expression systems and instrumentation for high-throughput screening that should yield improved fluorescent proteins for advanced imaging applications. PMID:22127219

  4. Matlab GUI for a Fluid Mixer

    NASA Technical Reports Server (NTRS)

    Barbieri, Enrique

    2005-01-01

    The Test and Engineering Directorate at NASA John C. Stennis Space Center developed an interest to study the modeling, evaluation, and control of a liquid hydrogen (LH2) and gas hydrogen (GH2) mixer subsystem of a ground test facility. This facility carries out comprehensive ground-based testing and certification of liquid rocket engines including the Space Shuttle Main engine. A software simulation environment developed in MATLAB/SIMULINK (M/S) will allow NASA engineers to test rocket engine systems at relatively no cost. In the progress report submitted in February 2004, we described the development of two foundation programs, a reverse look-up application using various interpolation algorithms, a variety of search and return methods, and self-checking methods to reduce the error in returned search results to increase the functionality of the program. The results showed that these efforts were successful. To transfer this technology to engineers who are not familiar with the M/S environment, a four-module GUI was implemented allowing the user to evaluate the mixer model under open-loop and closed-loop conditions. The progress report was based on an udergraduate Honors Thesis by Ms. Jamie Granger Austin in the Department of Electrical Engineering and Computer Science at Tulane University, during January-May 2003, and her continued efforts during August-December 2003. In collaboration with Dr. Hanz Richter and Dr. Fernando Figueroa we published these results in a NASA Tech Brief due to appear this year. Although the original proposal in 2003 did not address other components of the test facility, we decided in the last few months to extend our research and consider a related pressurization tank component as well. This report summarizes the results obtained towards a Graphical User Interface (GUI) for the evaluation and control of the hydrogen mixer subsystem model and for the pressurization tank each taken individually. Further research would combine the two

  5. Temperature automation for a propellant mixer

    NASA Technical Reports Server (NTRS)

    Vincent, T. L.; Wilson, R. G.

    1990-01-01

    The analysis and installation of an automatic temperature controller on a propellant mixer is presented. Ultimately, the entire mixing process will come under automation, but since precise adherence to the temperature profile is very difficult to sustain manually, this was the first component to be automated. Automation is not only important for producing a uniform product, but it is necessary for envisioned space-based propellant production.

  6. 241-SY-101 mixer pump lifetime expectancy. Final report

    SciTech Connect

    Shaw, C.P.

    1995-12-08

    The purpose of WHC-SD-WM-TI-726, Rev. 0 241-SY-101 Mixer Pump Lifetime Expectancy is to determine a best estimate of the mean lifetime of non-repairable (located in the waste) essential features of the hydrogen mitigation mixer pump presently installed in 101-SY. The estimated mean lifetime is 9.1 years. This report does not demonstrate operation of the entire pump assembly within the Tank Farm ``safety envelope``. It was recognized by the Defense Nuclear Facilities Safety Board (DNFSB) this test pump was not specifically designed for long term service in tank 101-SY. In June 95 the DNFSB visited Hanford and ask the question, ``how long will this test pump last and how will the essential features fail?`` During the 2 day meeting with the DNFSB it was discussed and defined within the meeting just exactly what essential features of the pump must operate. These essential features would allow the pump to operate for the purpose of extending the window for replacement. Operating with only essential features would definitely be outside the operating safety envelope and would require a waiver. There are three essential features: 1. The pump itself (i.e. the impeller and motor) must operate 2. Nozzles and discharges leg must remain unplugged 3. The pump can be re-aimed, new waste targeted, even if manually.

  7. Aerodynamic Design Study of Advanced Multistage Axial Compressor

    NASA Technical Reports Server (NTRS)

    Larosiliere, Louis M.; Wood, Jerry R.; Hathaway, Michael D.; Medd, Adam J.; Dang, Thong Q.

    2002-01-01

    As a direct response to the need for further performance gains from current multistage axial compressors, an investigation of advanced aerodynamic design concepts that will lead to compact, high-efficiency, and wide-operability configurations is being pursued. Part I of this report describes the projected level of technical advancement relative to the state of the art and quantifies it in terms of basic aerodynamic technology elements of current design systems. A rational enhancement of these elements is shown to lead to a substantial expansion of the design and operability space. Aerodynamic design considerations for a four-stage core compressor intended to serve as a vehicle to develop, integrate, and demonstrate aerotechnology advancements are discussed. This design is biased toward high efficiency at high loading. Three-dimensional blading and spanwise tailoring of vector diagrams guided by computational fluid dynamics (CFD) are used to manage the aerodynamics of the high-loaded endwall regions. Certain deleterious flow features, such as leakage-vortex-dominated endwall flow and strong shock-boundary-layer interactions, were identified and targeted for improvement. However, the preliminary results were encouraging and the front two stages were extracted for further aerodynamic trimming using a three-dimensional inverse design method described in part II of this report. The benefits of the inverse design method are illustrated by developing an appropriate pressure-loading strategy for transonic blading and applying it to reblade the rotors in the front two stages of the four-stage configuration. Multistage CFD simulations based on the average passage formulation indicated an overall efficiency potential far exceeding current practice for the front two stages. Results of the CFD simulation at the aerodynamic design point are interrogated to identify areas requiring additional development. In spite of the significantly higher aerodynamic loadings, advanced CFD

  8. Proceedings of the Ninth Annual Summer Conference: NASA/USRA University Advanced Aeronautics Design Program and Advanced Space Design Program

    NASA Technical Reports Server (NTRS)

    1993-01-01

    The NASA/USRA University Advanced Design Program was established in 1984 as an attempt to add more and better design education to primarily undergraduate engineering programs. The original focus of the pilot program encompassing nine universities and five NASA centers was on space design. Two years later, the program was expanded to include aeronautics design with six universities and three NASA centers participating. This year marks the last of a three-year cycle of participation by forty-one universities, eight NASA centers, and one industry participant. The Advanced Space Design Program offers universities an opportunity to plan and design missions and hardware that would be of usc in the future as NASA enters a new era of exploration and discovery, while the Advanced Aeronautics Design Program generally offers opportunities for study of design problems closer to the present time, ranging from small, slow-speed vehicles to large, supersonic and hypersonic passenger transports. The systems approach to the design problem is emphasized in both the space and aeronautics projects. The student teams pursue the chosen problem during their senior year in a one- or two-semester capstone design course and submit a comprehensive written report at the conclusion of the project. Finally, student representatives from each of the universities summarize their work in oral presentations at the Annual Summer Conference, sponsored by one of the NASA centers and attended by the university faculty, NASA and USRA personnel and aerospace industry representatives. As the Advanced Design Program has grown in size, it has also matured in terms of the quality of the student projects. The present volume represents the student work accomplished during the 1992-1993 academic year reported at the Ninth Annual Summer Conference hosted by NASA Lyndon B. Johnson Space Center, June 14-18, 1993.

  9. Design, analysis and test verification of advanced encapsulation systems

    NASA Technical Reports Server (NTRS)

    Garcia, A., III

    1982-01-01

    An analytical methodology for advanced encapsulation designs was developed. From these methods design sensitivities are established for the development of photovoltaic module criteria and the definition of needed research tasks. Analytical models were developed to perform optical, thermal, electrical and analyses on candidate encapsulation systems. From these analyses several candidate systems were selected for qualification testing. Additionally, test specimens of various types are constructed and tested to determine the validity of the analysis methodology developed. Identified deficiencies and/or discrepancies between analytical models and relevant test data are corrected. Prediction capability of analytical models is improved. Encapsulation engineering generalities, principles, and design aids for photovoltaic module designers is generated.

  10. Development of Submillimeter SIS Mixers and Broadband HEMT Amplifiers

    NASA Technical Reports Server (NTRS)

    Zmuidzinas, J.

    2004-01-01

    This is the final technical report for NASA grant NAG5-9493. entitled "Development of Submillimeter SIS Mixers and Broadband HEMT Amplifiers". The goal of this project was to develop and demonstrate a new generation of superconducting tunnel junction (SIS) receivers with extremely wide instantaneous (intermediate-frequency, or IF) bandwidths. of order 12 GHz. along with the wideband low-noise microwave HEMT (high electron mobility transistor) amplifiers which follow the SIS mixer. These wideband SIS/HEMT receivers would allow rapid submillimeter wavelength spectral line surveys to be carried out, for instance with the NASA airborne observatory SOFIA. and could potentially be useful for future submillimeter space missions such as SAFIR. In addition, there are potential NASA earth science applications. such as the monitoring of the distribution of chemical species in the stratosphere and troposphere using the limb-sounding technique. The overall goals of this project have been achieved: a broadband 200-300 SIS receiver was designed and constructed, and was demonstrated in the field through a test run at the Caltech Submillimeter Observatory on Mauna Kea. HI. The technical details are described in the appendices. which are primarily conference publications. but Appendix A also includes an unpublished summary of the latest results. The work on the SIS mixer design are described in the conference publications (appendices B and C). The "Supermix" software package that was developed at Caltech and used for the SIS design is also described in two conference papers, but has been substantially revised, debugged. and extended as part of the work completed for this grant. The Supermix package is made available to the community at no charge. The electromagnetic design of a radial waveguide probe similar to the one used in this work is described in a journal publication. Details of the novel fabrication procedure used for producing the SIS devices at JPL are also given in an

  11. Advanced radial inflow turbine rotor program: Design and dynamic testing

    NASA Technical Reports Server (NTRS)

    Rodgers, C.

    1976-01-01

    The advancement of small, cooled, radial inflow turbine technology in the area of operation at higher turbine inlet temperature is discussed. The first step was accomplished by designing, fabricating, and subjecting to limited mechanical testing an advanced gas generator rotating assembly comprising a radial inflow turbine and two-stage centrifugal compressor. The radial inflow turbine and second-stage compressor were designed as an integrally machined monorotor with turbine cooling taking place basically by conduction to the compressor. Design turbine inlet rotor gas temperature, rotational speed, and overall gas generator compressor pressure ratio were 1422 K (2560 R), 71,222 rpm, and 10/1 respectively. Mechanical testing on a fabricated rotating assembly and bearing system covered 1,000 cold start/stop cycles and three spins to 120 percent design speed (85,466 rpm).

  12. Advanced Turbine Systems Program: Conceptual design and product development

    SciTech Connect

    1996-12-31

    Objective is to provide the conceptual design and product development plant for an ultra high efficiency, environmentally superior, and cost competitive industrial gas turbine system to be commercialized by the year 2000 (secondary objective is to begin early development of technologies critical to the success of ATS). This report addresses the remaining 7 of the 9 subtasks in Task 8, Design and Test of Critical Components: catalytic combustion, recuperator, high- temperature turbine disc, advanced control system, and ceramic materials.

  13. Advanced stratified charge rotary aircraft engine design study

    NASA Technical Reports Server (NTRS)

    Badgley, P.; Berkowitz, M.; Jones, C.; Myers, D.; Norwood, E.; Pratt, W. B.; Ellis, D. R.; Huggins, G.; Mueller, A.; Hembrey, J. H.

    1982-01-01

    A technology base of new developments which offered potential benefits to a general aviation engine was compiled and ranked. Using design approaches selected from the ranked list, conceptual design studies were performed of an advanced and a highly advanced engine sized to provide 186/250 shaft Kw/HP under cruise conditions at 7620/25,000 m/ft altitude. These are turbocharged, direct-injected stratified charge engines intended for commercial introduction in the early 1990's. The engine descriptive data includes tables, curves, and drawings depicting configuration, performance, weights and sizes, heat rejection, ignition and fuel injection system descriptions, maintenance requirements, and scaling data for varying power. An engine-airframe integration study of the resulting engines in advanced airframes was performed on a comparative basis with current production type engines. The results show airplane performance, costs, noise & installation factors. The rotary-engined airplanes display substantial improvements over the baseline, including 30 to 35% lower fuel usage.

  14. Microfluidic Mixers for Studying Protein Folding

    PubMed Central

    Waldauer, Steven A.; Wu, Ling; Yao, Shuhuai; Bakajin, Olgica; Lapidus, Lisa J.

    2012-01-01

    The process by which a protein folds into its native conformation is highly relevant to biology and human health yet still poorly understood. One reason for this is that folding takes place over a wide range of timescales, from nanoseconds to seconds or longer, depending on the protein1. Conventional stopped-flow mixers have allowed measurement of folding kinetics starting at about 1 ms. We have recently developed a microfluidic mixer that dilutes denaturant ~100-fold in ~8 μs2. Unlike a stopped-flow mixer, this mixer operates in the laminar flow regime in which turbulence does not occur. The absence of turbulence allows precise numeric simulation of all flows within the mixer with excellent agreement to experiment3-4. Laminar flow is achieved for Reynolds numbers Re ≤100. For aqueous solutions, this requires micron scale geometries. We use a hard substrate, such as silicon or fused silica, to make channels 5-10 μm wide and 10 μm deep (See Figure 1). The smallest dimensions, at the entrance to the mixing region, are on the order of 1 μm in size. The chip is sealed with a thin glass or fused silica coverslip for optical access. Typical total linear flow rates are ~1 m/s, yielding Re~10, but the protein consumption is only ~0.5 nL/s or 1.8 μL/hr. Protein concentration depends on the detection method: For tryptophan fluorescence the typical concentration is 100 μM (for 1 Trp/protein) and for FRET the typical concentration is ~100 nM. The folding process is initiated by rapid dilution of denaturant from 6 M to 0.06 M guanidine hydrochloride. The protein in high denaturant flows down a central channel and is met on either side at the mixing region by buffer without denaturant moving ~100 times faster (see Figure 2). This geometry causes rapid constriction of the protein flow into a narrow jet ~100 nm wide. Diffusion of the light denaturant molecules is very rapid, while diffusion of the heavy protein molecules is much slower, diffusing less than 1 μm in 1 ms

  15. Advanced EVA system design requirements study, executive summary

    NASA Technical Reports Server (NTRS)

    1986-01-01

    Design requirements and criteria for the space station advanced Extravehicular Activity System (EVAS) including crew enclosures, portable life support systems, maneuvering propulsion systems, and related EVA support equipment were established. The EVA mission requirements, environments, and medical and physiological requirements, as well as operational, procedures and training issues were considered.

  16. Advance Approach to Concept and Design Studies for Space Missions

    NASA Technical Reports Server (NTRS)

    Deutsch, M.; Nichols, J.

    1999-01-01

    Recent automated and advanced techniques developed at JPL have created a streamlined and fast-track approach to initial mission conceptualization and system architecture design, answering the need for rapid turnaround of trade studies for potential proposers, as well as mission and instrument study groups.

  17. Cost and accuracy of advanced breeding trial designs in apple

    PubMed Central

    Harshman, Julia M; Evans, Kate M; Hardner, Craig M

    2016-01-01

    Trialing advanced candidates in tree fruit crops is expensive due to the long-term nature of the planting and labor-intensive evaluations required to make selection decisions. How closely the trait evaluations approximate the true trait value needs balancing with the cost of the program. Designs of field trials of advanced apple candidates in which reduced number of locations, the number of years and the number of harvests per year were modeled to investigate the effect on the cost and accuracy in an operational breeding program. The aim was to find designs that would allow evaluation of the most additional candidates while sacrificing the least accuracy. Critical percentage difference, response to selection, and correlated response were used to examine changes in accuracy of trait evaluations. For the quality traits evaluated, accuracy and response to selection were not substantially reduced for most trial designs. Risk management influences the decision to change trial design, and some designs had greater risk associated with them. Balancing cost and accuracy with risk yields valuable insight into advanced breeding trial design. The methods outlined in this analysis would be well suited to other horticultural crop breeding programs. PMID:27019717

  18. Experimental evaluation of exhaust mixers for an Energy Efficient Engine

    NASA Technical Reports Server (NTRS)

    Kozlowski, H.; Kraft, G.

    1980-01-01

    Static scale model tests were conducted to evaluate exhaust system mixers for a high bypass ratio engine as part of the NASA sponsored Energy Efficient program. Gross thrust coefficients were measured for a series of mixer configurations which included variations in the number of mixer lobes, tailpipe length, mixer penetration, and length. All of these parameters have a significant impact on exhaust system performance. In addition, flow visualization pictures and pressure/temperature traverses were obtained for selected configurations. Parametric performance trends are discussed and the results considered relative to the Energy Efficient Engine program goals.

  19. Advanced Technology Spark-Ignition Aircraft Piston Engine Design Study

    NASA Technical Reports Server (NTRS)

    Stuckas, K. J.

    1980-01-01

    The advanced technology, spark ignition, aircraft piston engine design study was conducted to determine the improvements that could be made by taking advantage of technology that could reasonably be expected to be made available for an engine intended for production by January 1, 1990. Two engines were proposed to account for levels of technology considered to be moderate risk and high risk. The moderate risk technology engine is a homogeneous charge engine operating on avgas and offers a 40% improvement in transportation efficiency over present designs. The high risk technology engine, with a stratified charge combustion system using kerosene-based jet fuel, projects a 65% improvement in transportation efficiency. Technology enablement program plans are proposed herein to set a timetable for the successful integration of each item of required advanced technology into the engine design.

  20. Advanced Turbine Systems (ATS) program conceptual design and product development

    SciTech Connect

    1996-08-31

    Achieving the Advanced Turbine Systems (ATS) goals of 60% efficiency, single-digit NO{sub x}, and 10% electric power cost reduction imposes competing characteristics on the gas turbine system. Two basic technical issues arise from this. The turbine inlet temperature of the gas turbine must increase to achieve both efficiency and cost goals. However, higher temperatures move in the direction of increased NO{sub x} emission. Improved coatings and materials technologies along with creative combustor design can result in solutions to achieve the ultimate goal. GE`s view of the market, in conjunction with the industrial and utility objectives, requires the development of Advanced Gas Turbine Systems which encompass two potential products: a new aeroderivative combined-cycle system for the industrial market, and a combined-cycle system for the utility sector that is based on an advanced frame machine. The GE Advanced Gas Turbine Development program is focused on two specific products: (1) a 70 MW class industrial gas turbine based on the GE90 core technology utilizing an innovative air cooling methodology; (2) a 200 MW class utility gas turbine based on an advanced Ge heavy-duty machine utilizing advanced cooling and enhancement in component efficiency. Both of these activities required the identification and resolution of technical issues critical to achieving ATS goals. The emphasis for the industrial ATS was placed upon innovative cycle design and low emission combustion. The emphasis for the utility ATS was placed on developing a technology base for advanced turbine cooling, while utilizing demonstrated and planned improvements in low emission combustion. Significant overlap in the development programs will allow common technologies to be applied to both products. GE Power Systems is solely responsible for offering GE products for the industrial and utility markets.

  1. Advances in Experiment Design for High Performance Aircraft

    NASA Technical Reports Server (NTRS)

    Morelli, Engene A.

    1998-01-01

    A general overview and summary of recent advances in experiment design for high performance aircraft is presented, along with results from flight tests. General theoretical background is included, with some discussion of various approaches to maneuver design. Flight test examples from the F-18 High Alpha Research Vehicle (HARV) are used to illustrate applications of the theory. Input forms are compared using Cramer-Rao bounds for the standard errors of estimated model parameters. Directions for future research in experiment design for high performance aircraft are identified.

  2. Advanced computational research in materials processing for design and manufacturing

    SciTech Connect

    Zacharia, T.

    1994-12-31

    The computational requirements for design and manufacture of automotive components have seen dramatic increases for producing automobiles with three times the mileage. Automotive component design systems are becoming increasingly reliant on structural analysis requiring both overall larger analysis and more complex analyses, more three-dimensional analyses, larger model sizes, and routine consideration of transient and non-linear effects. Such analyses must be performed rapidly to minimize delays in the design and development process, which drives the need for parallel computing. This paper briefly describes advanced computational research in superplastic forming and automotive crash worthiness.

  3. Advanced Control Design for Wind Turbines; Part I: Control Design, Implementation, and Initial Tests

    SciTech Connect

    Wright, A. D.; Fingersh, L. J.

    2008-03-01

    The purpose of this report is to give wind turbine engineers information and examples of the design, testing through simulation, field implementation, and field testing of advanced wind turbine controls.

  4. Advanced hydrogen/oxygen thrust chamber design analysis

    NASA Technical Reports Server (NTRS)

    Shoji, J. M.

    1973-01-01

    The results are reported of the advanced hydrogen/oxygen thrust chamber design analysis program. The primary objectives of this program were to: (1) provide an in-depth analytical investigation to develop thrust chamber cooling and fatigue life limitations of an advanced, high pressure, high performance H2/O2 engine design of 20,000-pounds (88960.0 N) thrust; and (2) integrate the existing heat transfer analysis, thermal fatigue and stress aspects for advanced chambers into a comprehensive computer program. Thrust chamber designs and analyses were performed to evaluate various combustor materials, coolant passage configurations (tubes and channels), and cooling circuits to define the nominal 1900 psia (1.31 x 10 to the 7th power N/sq m) chamber pressure, 300-cycle life thrust chamber. The cycle life capability of the selected configuration was then determined for three duty cycles. Also the influence of cycle life and chamber pressure on thrust chamber design was investigated by varying in cycle life requirements at the nominal chamber pressure and by varying the chamber pressure at the nominal cycle life requirement.

  5. Design of the advanced regional aircraft, the DART-75

    NASA Technical Reports Server (NTRS)

    Elliot, Steve; Gislason, Jason; Huffstetler, Mark; Mann, Jon; Withers, Ashley; Zimmerman, Mark

    1992-01-01

    The need for regional aircraft stems from the problem of hub airport congestion. Regional travel will allow a passenger to commute from one spoke city to another spoke city without entering the congested hub airport. In addition, those people traveling longer routes may begin the flight at home instead of traveling to the hub airport. At this time, there is no American aerospace company that produces a regional transport for under 100 passengers. The intention of the Developmental Advanced Regional Transport (DART-75) is to fill this void with a modern, efficient regional aircraft. This design achieves the efficiency through a number of advanced features including three lifting surfaces, partial composite construction, and an advanced engine design. Efficiency is not the only consideration. Structural integrity, fatigue life, ease of maintenance, passenger comfort and convenience, and environmental aspects must all be considered. These factors force the design team to face many tradeoffs that are studied to find the best solution. The final consideration that cannot be overlooked is that of cost. The DART-75 is a 75-passenger medium-range regional transport intended for spoke-to-spoke, spoke-to-hub, and some hub-to-hub operations. Included are the general descriptions of the structures, weight and balance, stability and control, performance, and engine design.

  6. Development of environmentally advanced hydropower turbine system design concepts

    SciTech Connect

    Franke, G.F.; Webb, D.R.; Fisher, R.K. Jr.

    1997-08-01

    A team worked together on the development of environmentally advanced hydro turbine design concepts to reduce hydropower`s impact on the environment, and to improve the understanding of the technical and environmental issues involved, in particular, with fish survival as a result of their passage through hydro power sites. This approach brought together a turbine design and manufacturing company, biologists, a utility, a consulting engineering firm and a university research facility, in order to benefit from the synergy of diverse disciplines. Through a combination of advanced technology and engineering analyses, innovative design concepts adaptable to both new and existing hydro facilities were developed and are presented. The project was divided into 4 tasks. Task 1 investigated a broad range of environmental issues and how the issues differed throughout the country. Task 2 addressed fish physiology and turbine physics. Task 3 investigated individual design elements needed for the refinement of the three concept families defined in Task 1. Advanced numerical tools for flow simulation in turbines are used to quantify characteristics of flow and pressure fields within turbine water passageways. The issues associated with dissolved oxygen enhancement using turbine aeration are presented. The state of the art and recent advancements of this technology are reviewed. Key elements for applying turbine aeration to improve aquatic habitat are discussed and a review of the procedures for testing of aerating turbines is presented. In Task 4, the results of the Tasks were assembled into three families of design concepts to address the most significant issues defined in Task 1. The results of the work conclude that significant improvements in fish passage survival are achievable.

  7. Advanced Electric Submersible Pump Design Tool for Geothermal Applications

    SciTech Connect

    Xuele Qi; Norman Turnquist; Farshad Ghasripoor

    2012-05-31

    Electrical Submersible Pumps (ESPs) present higher efficiency, larger production rate, and can be operated in deeper wells than the other geothermal artificial lifting systems. Enhanced Geothermal Systems (EGS) applications recommend lifting 300 C geothermal water at 80kg/s flow rate in a maximum 10-5/8-inch diameter wellbore to improve the cost-effectiveness. In this paper, an advanced ESP design tool comprising a 1D theoretical model and a 3D CFD analysis has been developed to design ESPs for geothermal applications. Design of Experiments was also performed to optimize the geometry and performance. The designed mixed-flow type centrifugal impeller and diffuser exhibit high efficiency and head rise under simulated EGS conditions. The design tool has been validated by comparing the prediction to experimental data of an existing ESP product.

  8. Turbofan forced mixer lobe flow modeling. 2: Three-dimensional inviscid mixer analysis (FLOMIX)

    NASA Technical Reports Server (NTRS)

    Barber, T.

    1988-01-01

    A three-dimensional potential analysis (FLOMIX) was formulated and applied to the inviscid flow over a turbofan foced mixer. The method uses a small disturbance formulation to analytically uncouple the circumferential flow from the radial and axial flow problem, thereby reducing the analysis to the solution of a series of axisymmetric problems. These equations are discretized using a flux volume formulation along a Cartesian grid. The method extends earlier applications of the Cartesian method to complex cambered geometries. The effects of power addition are also included within the potential formulation. Good agreement is obtained with an alternate small disturbance analysis for a high penetration symmetric mixer in a planar duct. In addition, calculations showing pressure distributions and induced secondary vorticity fields are presented for practical trubofan mixer configurations, and where possible, comparison was made with available experimental data. A detailed description of the required data input and coordinate definition is presented along with a sample data set for a practical forced mixer configuration. A brief description of the program structure and subroutines is also provided.

  9. Superconducting Mixers for Far-Infrared Spectroscopy

    NASA Technical Reports Server (NTRS)

    Betz, A. L.; Boreiko, R. T.; Grossman, E. R.; Reintsema, C. D.; Ono, R. H.; Gerecht, E.

    2002-01-01

    The goal of this project was to fabricate and test planar arrays of superconducting mixers for the 2-6 THz band. The technology is intended for multi-beam receivers aboard Explorer-class missions and the SOFIA Airborne Observatory. The mixer technology is the superconducting transition-edge microbolometer, which is more commonly known as the Hot-Electron micro-Bolometer (HEB). As originally proposed, two superconducting technologies were to be developed: (1) low-Tc niobium HEBs which could approach quantum-noise-limited sensitivities but require cooling to 2- 4 K, and (2) high-Tc YBCO HEBs with sensitivities 10 times worse but with a relaxed cooling requirement of 30-60 K. The low-Tc devices would be best for astronomy applications on SOFIA, whereas the high-Tc devices would be more suitable for planetary missions using systems without stored cryogens. The work plan called for planar micro-fabrication and initial testing of HEB devices at the NIST Boulder clean-room facility. Subsequent assembly and RF testing of selected devices would be done at the CASA laboratory at U. Colorado. Approximately 1-year after work began on this project, Dr. Eyal Gerecht joined the NIST group, and assumed day-to-day responsibility for Nb-HEB development at NIST outside of micro-fabrication. The YBCO-HEB work was to be guided by Dr. Ron Ono, who was the NIST expert in YBCO technology. Unfortunately, recurrent health problems limited the time Ron could devote to the project in its first year. These problems became aggravated in early 2001, and sadly led to Ron's death in October, 2001. His loss was not only a blow to his friends and associates at NIST, but was mounted by the US superconductivity community at large. With his passing, work on high-Tc HEBs ceased at NIST. There was no one to replace him or his expertise. Our work subsequently shifted solely to Nb-HEB devices. In the sections which follow, our progress in the development of diffusion-cooled Nb-HEB mixers is detailed. To

  10. Computational studies of lobed forced mixer flows

    NASA Astrophysics Data System (ADS)

    Hu, H.; Wu, S. S.; Yu, S. C. M.

    1998-03-01

    Full Navier-Stokes Analyses have been conducted for the flows behind the trailing edge of a lobed forced mixer. The governing equations are derived from the time-dependent compressible Navier-Stokes equations and discretized in the finite-difference form. A simple two-layer eddy viscosity model has also been used to account for the turbulence. Computed results are compared with some of the velocity measurements using a laser-Doppler anemometer (Yu and Yip (1997)). In general, good agreement can be obtained in the streamwise mean velocity distribution but the decay of the streamwise circulation is underpredicted. Some suggestions to the discrepancy are proposed.

  11. PULSED MIXER-SETTLER SOLVENT EXTRACTION CONTACTORS

    DOEpatents

    Figg, W.S.

    1958-08-12

    A mixer-settler extractor is described for contacting immiscible liquids having different specific gravities in order to withdraw one or more components from one liquid with the aid of the other liquid. The extractor consists of a hollow column, a rotary drive shafi extending : through the column with a number of impellers spaced thereon, an equal nunnber of separator plate sets each consisting of one fluorothene and one stainless steel plate with peripheral recesses and flow slots mounted on the column, and a pulse generator. This apparatus is particularly useful in solvent extraction processes for recovering plutonium from aqueous acidic solutions of irradiated uranium.

  12. Biasable, Balanced, Fundamental Submillimeter Monolithic Membrane Mixer

    NASA Technical Reports Server (NTRS)

    Siegel, Peter; Schlecht, Erich; Mehdi, Imran; Gill, John; Velebir, James; Tsang, Raymond; Dengler, Robert; Lin, Robert

    2010-01-01

    This device is a biasable, submillimeter-wave, balanced mixer fabricated using JPL s monolithic membrane process a simplified version of planar membrane technology. The primary target application is instrumentation used for analysis of atmospheric constituents, pressure, temperature, winds, and other physical and chemical properties of the atmospheres of planets and comets. Other applications include high-sensitivity gas detection and analysis. This innovation uses a balanced configuration of two diodes allowing the radio frequency (RF) signal and local oscillator (LO) inputs to be separated. This removes the need for external diplexers that are inherently narrowband, bulky, and require mechanical tuning to change frequency. Additionally, this mixer uses DC bias-ability to improve its performance and versatility. In order to solve problems relating to circuit size, the GaAs membrane process was created. As much of the circuitry as possible is fabricated on-chip, making the circuit monolithic. The remainder of the circuitry is precision-machined into a waveguide block that holds the GaAs circuit. The most critical alignments are performed using micron-scale semiconductor technology, enabling wide bandwidth and high operating frequencies. The balanced mixer gets superior performance with less than 2 mW of LO power. This can be provided by a simple two-stage multiplier chain following an amplifier at around 90 GHz. Further, the diodes are arranged so that they can be biased. Biasing pushes the diodes closer to their switching voltage, so that less LO power is required to switch the diodes on and off. In the photo, the diodes are at the right end of the circuit. The LO comes from the waveguide at the right into a reduced-height section containing the diodes. Because the diodes are in series to the LO signal, they are both turned on and off simultaneously once per LO cycle. Conversely, the RF signal is picked up from the RF waveguide by the probe at the left, and flows

  13. Advanced Free Flight Planner and Dispatcher's Workstation: Preliminary Design Specification

    NASA Technical Reports Server (NTRS)

    Wilson, J.; Wright, C.; Couluris, G. J.

    1997-01-01

    The National Aeronautics and Space Administration (NASA) has implemented the Advanced Air Transportation Technology (AATT) program to investigate future improvements to the national and international air traffic management systems. This research, as part of the AATT program, developed preliminary design requirements for an advanced Airline Operations Control (AOC) dispatcher's workstation, with emphasis on flight planning. This design will support the implementation of an experimental workstation in NASA laboratories that would emulate AOC dispatch operations. The work developed an airline flight plan data base and specified requirements for: a computer tool for generation and evaluation of free flight, user preferred trajectories (UPT); the kernel of an advanced flight planning system to be incorporated into the UPT-generation tool; and an AOC workstation to house the UPT-generation tool and to provide a real-time testing environment. A prototype for the advanced flight plan optimization kernel was developed and demonstrated. The flight planner uses dynamic programming to search a four-dimensional wind and temperature grid to identify the optimal route, altitude and speed for successive segments of a flight. An iterative process is employed in which a series of trajectories are successively refined until the LTPT is identified. The flight planner is designed to function in the current operational environment as well as in free flight. The free flight environment would enable greater flexibility in UPT selection based on alleviation of current procedural constraints. The prototype also takes advantage of advanced computer processing capabilities to implement more powerful optimization routines than would be possible with older computer systems.

  14. Broadband quasi-optical SIS mixers with large area junctions

    NASA Astrophysics Data System (ADS)

    Pance, Gordana; Wengler, Micheal J.

    1994-04-01

    A broadband quasi-optical superconducting tunnel junction (SIS) mixer with integrated tuning elements was designed and tested. We are able to achieve very low noise performance using commercially available niobium integrated circuit (IC) technology. The low critical current density (980 A/sq cm) and large area (12 sq micron) of the commercial SIS's is compensated by the ability to fabricate accurate integrated tuning structures in the mature niobium IC process available from Hypres, Inc. Noise measurements were made in the frequency range from 70 to 105 GHz. The best uncorrected double sideband receiver noise is 38 K at 77 GHz, with receiver noise temperatures less than 100 K from 75 to 102 GHz.

  15. Soft computing in design and manufacturing of advanced materials

    NASA Technical Reports Server (NTRS)

    Cios, Krzysztof J.; Baaklini, George Y; Vary, Alex

    1993-01-01

    The potential of fuzzy sets and neural networks, often referred to as soft computing, for aiding in all aspects of manufacturing of advanced materials like ceramics is addressed. In design and manufacturing of advanced materials, it is desirable to find which of the many processing variables contribute most to the desired properties of the material. There is also interest in real time quality control of parameters that govern material properties during processing stages. The concepts of fuzzy sets and neural networks are briefly introduced and it is shown how they can be used in the design and manufacturing processes. These two computational methods are alternatives to other methods such as the Taguchi method. The two methods are demonstrated by using data collected at NASA Lewis Research Center. Future research directions are also discussed.

  16. Preliminary aerodynamic design considerations for advanced laminar flow aircraft configurations

    NASA Technical Reports Server (NTRS)

    Johnson, Joseph L., Jr.; Yip, Long P.; Jordan, Frank L., Jr.

    1986-01-01

    Modern composite manufacturing methods have provided the opportunity for smooth surfaces that can sustain large regions of natural laminar flow (NLF) boundary layer behavior and have stimulated interest in developing advanced NLF airfoils and improved aircraft designs. Some of the preliminary results obtained in exploratory research investigations on advanced aircraft configurations at the NASA Langley Research Center are discussed. Results of the initial studies have shown that the aerodynamic effects of configuration variables such as canard/wing arrangements, airfoils, and pusher-type and tractor-type propeller installations can be particularly significant at high angles of attack. Flow field interactions between aircraft components were shown to produce undesirable aerodynamic effects on a wing behind a heavily loaded canard, and the use of properly designed wing leading-edge modifications, such as a leading-edge droop, offset the undesirable aerodynamic effects by delaying wing stall and providing increased stall/spin resistance with minimum degradation of laminar flow behavior.

  17. Conceptual design study: Forest Fire Advanced System Technology (FFAST)

    NASA Technical Reports Server (NTRS)

    Nichols, J. D.; Warren, J. R.

    1986-01-01

    An integrated forest fire detection and mapping system that will be based upon technology available in the 1990s was defined. Uncertainties in emerging and advanced technologies related to the conceptual design were identified and recommended for inclusion as preferred system components. System component technologies identified for an end-to-end system include thermal infrared, linear array detectors, automatic georeferencing and signal processing, geosynchronous satellite communication links, and advanced data integration and display. Potential system configuration options were developed and examined for possible inclusion in the preferred system configuration. The preferred system configuration will provide increased performance and be cost effective over the system currently in use. Forest fire management user requirements and the system component emerging technologies were the basis for the system configuration design. A preferred system configuration was defined that warrants continued refinement and development, examined economic aspects of the current and preferred system, and provided preliminary cost estimates for follow-on system prototype development.

  18. An advanced Ni-Cd battery cell design

    NASA Technical Reports Server (NTRS)

    Miller, L.

    1986-01-01

    The evolution of an advanced Ni-Cd space battery cell design continues to prove very promising. High oxygen/hydrogen gas recombination rates (currently up to a C/5 charge rate) and increased electrolyte activation level tolerance (currently up to 5.6 grams Ah of positive capacity) were demonstrated by test. A superior performance, extended life battery cell offering advantages should soon be available for mission applications

  19. Advanced turbine systems program conceptual design and product development

    NASA Astrophysics Data System (ADS)

    1995-01-01

    This report describes progress made in the advanced turbine systems program conceptual design and product development. The topics of the report include selection of the Allison GFATS, castcool technology development for industrial engines test plan and schedule, code development and background gathering phase for the ultra low NOx combustion technology task, active turbine clearance task, and water vapor/air mixture cooling of turbine vanes task.

  20. AGBT Advanced Counter-Rotating Gearbox Detailed Design Report

    NASA Technical Reports Server (NTRS)

    Howe, D. C.; Sundt, C. V.; Mckibbon, A. H.

    1988-01-01

    An Advanced Counter-Rotating (CR) Gearbox was designed and fabricated to evaluate gearbox efficiency, durability and weight characteristics for emerging propfan-powered airplanes. Component scavenge tests showed that a constant volume collector had high scavenge effectiveness, which was uneffected by added airflow. Lubrication tests showed that gearbox losses could be reduced by controlling the air/oil mixture and by directing the oil jets radially, with a slight axial component, into the sun/planet gears.

  1. Aircraft systems design studies employing advanced transport technologies

    NASA Technical Reports Server (NTRS)

    Downie, B.; Pearce, C.; Quartero, C.; Taylor, A.

    1972-01-01

    System and design integration studies are presented to define and assess the application of the advanced technology most likely to result in a superior next generation, high subsonic/sonic conventional takeoff and landing transport aircraft system. It is concluded that the new technologies can be directed toward the achievement of improved economy and performance. These benefits may be used to compensate for the penalties associated with reduced noise requirements anticipated to make future aircraft ecologically acceptable.

  2. Test model designs for advanced refractory ceramic materials

    NASA Technical Reports Server (NTRS)

    Tran, Huy Kim

    1993-01-01

    The next generation of space vehicles will be subjected to severe aerothermal loads and will require an improved thermal protection system (TPS) and other advanced vehicle components. In order to ensure the satisfactory performance system (TPS) and other advanced vehicle materials and components, testing is to be performed in environments similar to space flight. The design and fabrication of the test models should be fairly simple but still accomplish test objectives. In the Advanced Refractory Ceramic Materials test series, the models and model holders will need to withstand the required heat fluxes of 340 to 817 W/sq cm or surface temperatures in the range of 2700 K to 3000 K. The model holders should provide one dimensional (1-D) heat transfer to the samples and the appropriate flow field without compromising the primary test objectives. The optical properties such as the effective emissivity, catalytic efficiency coefficients, thermal properties, and mass loss measurements are also taken into consideration in the design process. Therefore, it is the intent of this paper to demonstrate the design schemes for different models and model holders that would accommodate these test requirements and ensure the safe operation in a typical arc jet facility.

  3. Advanced 3D inverse method for designing turbomachine blades

    SciTech Connect

    Dang, T.

    1995-10-01

    To meet the goal of 60% plant-cycle efficiency or better set in the ATS Program for baseload utility scale power generation, several critical technologies need to be developed. One such need is the improvement of component efficiencies. This work addresses the issue of improving the performance of turbo-machine components in gas turbines through the development of an advanced three-dimensional and viscous blade design system. This technology is needed to replace some elements in current design systems that are based on outdated technology.

  4. Advanced Sensor Fish Device for ImprovedTurbine Design

    SciTech Connect

    Carlson, Thomas J.

    2009-09-14

    Juvenile salmon (smolts) passing through hydroelectric turbines are subjected to environmental conditions that can potentially kill or injure them. Many turbines are reaching the end of their operational life expectancies and will be replaced with new turbines that incorporate advanced “fish friendly” designs devised to prevent injury and death to fish. To design a fish friendly turbine, it is first necessary to define the current conditions fish encounter. One such device used by biologists at Pacific Northwest National Laboratory was the sensor fish device to collect data that measures the forces fish experience during passage through hydroelectric projects.

  5. Advanced 3D inverse method for designing turbomachine blades

    SciTech Connect

    Dang, T.

    1995-12-31

    To meet the goal of 60% plant-cycle efficiency or better set in the ATS Program for baseload utility scale power generation, several critical technologies need to be developed. One such need is the improvement of component efficiencies. This work addresses the issue of improving the performance of turbo-machine components in gas turbines through the development of an advanced three-dimensional and viscous blade design system. This technology is needed to replace some elements in current design systems that are based on outdated technology.

  6. Advanced composites: Design and application. Proceedings of the meeting of the Mechanical Failures Prevention Group

    NASA Technical Reports Server (NTRS)

    Shives, T. R.; Willard, W. A.

    1979-01-01

    The design and application of advanced composites is discussed with emphasis on aerospace, aircraft, automotive, marine, and industrial applications. Failure modes in advanced composites are also discussed.

  7. 21 CFR 868.5330 - Breathing gas mixer.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Breathing gas mixer. 868.5330 Section 868.5330 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5330 Breathing gas mixer....

  8. 21 CFR 868.5330 - Breathing gas mixer.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Breathing gas mixer. 868.5330 Section 868.5330 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5330 Breathing gas mixer....

  9. 21 CFR 868.5330 - Breathing gas mixer.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Breathing gas mixer. 868.5330 Section 868.5330 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5330 Breathing gas mixer....

  10. 21 CFR 868.5330 - Breathing gas mixer.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Breathing gas mixer. 868.5330 Section 868.5330 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5330 Breathing gas mixer....

  11. Advanced designs for IPV nickel-hydrogen cells

    NASA Technical Reports Server (NTRS)

    Smithrick, J. J.; Manzo, M. A.; Gonzalez-Sanabria, O. D.

    1984-01-01

    Advanced designs for individual pressure vessel nickel-hydrogen cells have been concieved which should improve the cycle life at deep depths-of-discharge. Features of the designs which are new and not incorporated in either of the contemporary cells (Air Force/Hughes, Comsat) are: (1) use of alternate methods of oxygen recombination, (2) use of serrated edge separators to facilitate movement of gas within the cell while still maintaining required physical contact with the wall wick, and (3) use of an expandable stack to accommodate some of the nickel electrode expansion. The designs also consider electrolyte volume requirements over the life of the cells, and are fully compatible with the Air Force/Hughes design.

  12. An integrated computer system for preliminary design of advanced aircraft.

    NASA Technical Reports Server (NTRS)

    Fulton, R. E.; Sobieszczanski, J.; Landrum, E. J.

    1972-01-01

    A progress report is given on the first phase of a research project to develop a system of Integrated Programs for Aerospace-Vehicle Design (IPAD) which is intended to automate to the largest extent possible the preliminary and detailed design of advanced aircraft. The approach used is to build a pilot system and simultaneously to carry out two major contractual studies to define a practical IPAD system preparatory to programing. The paper summarizes the specifications and goals of the IPAD system, the progress to date, and any conclusion reached regarding its feasibility and scope. Sample calculations obtained with the pilot system are given for aircraft preliminary designs optimized with respect to discipline parameters, such as weight or L/D, and these results are compared with designs optimized with respect to overall performance parameters, such as range or payload.

  13. Preliminary design study of advanced multistage axial flow core compressors

    NASA Technical Reports Server (NTRS)

    Wisler, D. C.; Koch, C. C.; Smith, L. H., Jr.

    1977-01-01

    A preliminary design study was conducted to identify an advanced core compressor for use in new high-bypass-ratio turbofan engines to be introduced into commercial service in the 1980's. An evaluation of anticipated compressor and related component 1985 state-of-the-art technology was conducted. A parametric screening study covering a large number of compressor designs was conducted to determine the influence of the major compressor design features on efficiency, weight, cost, blade life, aircraft direct operating cost, and fuel usage. The trends observed in the parametric screening study were used to develop three high-efficiency, high-economic-payoff compressor designs. These three compressors were studied in greater detail to better evaluate their aerodynamic and mechanical feasibility.

  14. The design of an advanced CCD timing generator

    NASA Astrophysics Data System (ADS)

    Cheng, Guimei; Wu, Songbo; Wan, Min; Bao, Bin; Deng, JueQiong; Duan, Jing

    2015-10-01

    This paper describes how to design and develop an advanced Charge Coupled Device (CCD) timing generator which can obtain high precise CCD output signals. Above all, theory of the design and implementation of CCD timing generator is introduced based on Field Programmable Gate Array (FPGA) devices in detail. Secondly, it studies and analyzes the influencing factors that the waveform of CCD driving timing signals have on qualities of CCD output signals, which contain duty-cycle of HCCD clock, positive width of RST, signal-skew and delays among these signals. Then some skills are presented to improve and optimize the design in the phase of coding, compiling and placement and routing, which include code constraint, incremental placement and so on. Finally, simulation and verification of the design are performed with simulation tools, and hardware tests are carried out and experiment results are proved by oscilloscope.

  15. Aerodynamic Design Study of an Advanced Active Twist Rotor

    NASA Technical Reports Server (NTRS)

    Sekula, Martin K.; Wilbur, Matthew L.; Yeager, William T., Jr.

    2003-01-01

    An Advanced Active Twist Rotor (AATR) is currently being developed by the U.S. Army Vehicle Technology Directorate at NASA Langley Research Center. As a part of this effort, an analytical study was conducted to determine the impact of blade geometry on active-twist performance and, based on those findings, propose a candidate aerodynamic design for the AATR. The process began by creating a baseline design which combined the dynamic design of the original Active Twist Rotor and the aerodynamic design of a high lift rotor concept. The baseline model was used to conduct a series of parametric studies to examine the effect of linear blade twist and blade tip sweep, droop, and taper on active-twist performance. Rotor power requirements and hub vibration were also examined at flight conditions ranging from hover to advance ratio = 0.40. A total of 108 candidate designs were analyzed using the second-generation version of the Comprehensive Analytical Model of Rotorcraft Aerodynamics and Dynamics (CAMRAD II) code. The study concluded that the vibration reduction capabilities of a rotor utilizing controlled, strain-induced twisting are enhanced through the incorporation of blade tip sweep, droop, and taper into the blade design, while they are degraded by increasing the nose-down linear blade twist. Based on the analysis of rotor power, hub vibration, and active-twist response, a candidate aerodynamic design for the AATR consisting of a blade with approximately 10 degrees of linear blade twist and a blade tip design with 30 degree sweep, 10 degree droop, and 2.5:1 taper ratio over the outer five percent of the blade is proposed.

  16. Acoustic characteristics of externally blown flap systems with mixer nozzles

    NASA Technical Reports Server (NTRS)

    Goodykoontz, J. H.; Dorsch, R. G.; Wagner, J. M.

    1974-01-01

    Noise tests were conducted on a large scale, cold flow model of an engine-under-the-wing externally blown flap lift augmentation system employing a mixer nozzle. The mixer nozzle was used to reduce the flap impingement velocity and, consequently, try to attenuate the additional noise caused by the interaction between the jet exhaust and the wing flap. Results from the mixer nozzle tests are summarized and compared with the results for a conical nozzle. The comparison showed that with the mixer nozzle, less noise was generated when the trailing flap was in a typical landing setting (e.g., 60 deg). However, for a takeoff flap setting (20 deg), there was little or no difference in the acoustic characteristics when either the mixer or conical nozzle was used.

  17. Forest fire advanced system technology (FFAST) conceptual design study

    NASA Technical Reports Server (NTRS)

    Nichols, J. David; Warren, John R.

    1987-01-01

    The National Aeronautics and Space Administration's Jet Propulsion Laboratory (JPL) and the U.S. Department of Agriculture (USDA) Forest Service completed a conceptual design study that defined an integrated forest fire detection and mapping system that will be based upon technology available in the 1990s. Potential system configuration options in emerging and advanced technologies related to the conceptual design were identified and recommended for inclusion as preferred system components. System component technologies identified for an end-to-end system include airborne mounted, thermal infrared (IR) linear array detectors, automatic onboard georeferencing and signal processing, geosynchronous satellite communications links, and advanced data integration and display. Potential system configuration options were developed and examined for possible inclusion in the preferred system configuration. The preferred system configuration will provide increased performance and be cost effective over the system currently in use. Forest fire management user requirements and the system component emerging technologies were the basis for the system configuration design. The conceptual design study defined the preferred system configuration that warrants continued refinement and development, examined economic aspects of the current and preferred system, and provided preliminary cost estimates for follow-on system prototype development.

  18. Update on quadruple suspension design for Advanced LIGO

    NASA Astrophysics Data System (ADS)

    Aston, S. M.; Barton, M. A.; Bell, A. S.; Beveridge, N.; Bland, B.; Brummitt, A. J.; Cagnoli, G.; Cantley, C. A.; Carbone, L.; Cumming, A. V.; Cunningham, L.; Cutler, R. M.; Greenhalgh, R. J. S.; Hammond, G. D.; Haughian, K.; Hayler, T. M.; Heptonstall, A.; Heefner, J.; Hoyland, D.; Hough, J.; Jones, R.; Kissel, J. S.; Kumar, R.; Lockerbie, N. A.; Lodhia, D.; Martin, I. W.; Murray, P. G.; O'Dell, J.; Plissi, M. V.; Reid, S.; Romie, J.; Robertson, N. A.; Rowan, S.; Shapiro, B.; Speake, C. C.; Strain, K. A.; Tokmakov, K. V.; Torrie, C.; van Veggel, A. A.; Vecchio, A.; Wilmut, I.

    2012-12-01

    We describe the design of the suspension systems for the major optics for Advanced LIGO, the upgrade to LIGO—the Laser Interferometric Gravitational-Wave Observatory. The design is based on that used in GEO600—the German/UK interferometric gravitational wave detector, with further development to meet the more stringent noise requirements for Advanced LIGO. The test mass suspensions consist of a four-stage or quadruple pendulum for enhanced seismic isolation. To minimize suspension thermal noise, the final stage consists of a silica mirror, 40 kg in mass, suspended from another silica mass by four silica fibres welded to silica ears attached to the sides of the masses using hydroxide-catalysis bonding. The design is chosen to achieve a displacement noise level for each of the seismic and thermal noise contributions of 10-19 m/√Hz at 10 Hz, for each test mass. We discuss features of the design which has been developed as a result of experience with prototypes and associated investigations.

  19. Advanced Low-Noise Research Fan Stage Design

    NASA Technical Reports Server (NTRS)

    Neubert, Robert; Bock, Larry; Malmborg, Eric; Owen-Peer, William

    1997-01-01

    This report describes the design of the Advanced Low-Noise Research Fan stage. The fan is a variable pitch design, which is designed at the cruise pitch condition. Relative to the cruise setting, the blade is closed at takeoff and opened for reverse thrust operation. The fan stage is a split flow design with fan exit guide vanes (FEGVs) and core stators. The fan stage design is combined with a nacelle and engine core duct to form a powered fan/nacelle subscale model. This model is intended for use in combined aerodynamic, acoustic, and structural testing in a wind tunnel. The fan has an outer diameter of 22 in. and a hub-to-tip of 0.426 in., which allows the use of existing NASA fan and cowl force balance and rig drive systems. The design parameters were selected to permit valid acoustic and aerodynamic comparisons with the Pratt & Whitney (P&W) 17- and 22-in. rigs previously tested under NASA contract. The fan stage design is described in detail. The results of the design axisymmetric and Navier-Stokes aerodynamic analysis are presented at the critical design conditions. The structural analysis of the fan rotor and attachment is included. The blade and attachment are predicted to have adequate low-cycle fatigue life and an acceptable operating range without resonant stress or flutter. The stage was acoustically designed with airfoil counts in the FEGV and core stator to minimize noise. A fan/FEGV tone analysis developed separately under NASA contract was used to determine the optimum airfoil counts. The fan stage was matched to the existing nacelle, designed under the previous P&W low-noise contract, to form a fan/nacelle model for wind tunnel testing. It is an axisymmetric nacelle for convenience in testing and analysis. Previous testing confirmed that the nacelle performed as required at various aircraft operating conditions.

  20. LIGHT SOURCE: Conceptual design of Hefei advanced light source

    NASA Astrophysics Data System (ADS)

    Li, Wei-Min; Wang, Lin; Feng, Guang-Yao; Zhang, Shan-Cai; Wu, Cong-Feng; Xu, Hong-Liang; Liu, Zu-Ping

    2009-06-01

    The conceptual of Hefei Advanced Light Source, which is an advanced VUV and Soft X-ray source, was developed at NSRL of USTC. According to the synchrotron radiation user requirements and the trends of SR source development, some accelerator-based schemes were considered and compared; furthermore storage ring with ultra low emittance was adopted as the baseline scheme of HALS. To achieve ultra low emittance, some focusing structures were studied and optimized in the lattice design. Compromising of emittance, on-momentum and off-momentum dynamic aperture and ring scale, five bend acromat (FBA) was employed. In the preliminary design of HALS, the emittance was reduced to sub nm · rad, thus the radiation up to water window has full lateral coherence. The brilliance of undulator radiation covering several eVs to keVs range is higher than that of HLS by several orders. The HALS should be one of the most advanced synchrotron radiation light sources in the world.

  1. Numerical optimization design of advanced transonic wing configurations

    NASA Technical Reports Server (NTRS)

    Cosentino, G. B.; Holst, T. L.

    1984-01-01

    A computationally efficient and versatile technique for use in the design of advanced transonic wing configurations has been developed. A reliable and fast transonic wing flow-field analysis program, TWING, has been coupled with a modified quasi-Newton method, unconstrained optimization algorithm, QNMDIF, to create a new design tool. Fully three-dimensional wing designs utilizing both specified wing pressure distributions and drag-to-lift ration minimization as design objectives are demonstrated. Because of the high computational efficiency of each of the components of the design code, in particular the vectorization of TWING and the high speed of the Cray X-MP vector computer, the computer time required for a typical wing design is reduced by approximately an order of magnitude over previous methods. In the results presented here, this computed wave drag has been used as the quantity to be optimized (minimized) with great success, yielding wing designs with nearly shock-free (zero wave drag) pressure distributions and very reasonable wing section shapes.

  2. Adaptive Modeling, Engineering Analysis and Design of Advanced Aerospace Vehicles

    NASA Technical Reports Server (NTRS)

    Mukhopadhyay, Vivek; Hsu, Su-Yuen; Mason, Brian H.; Hicks, Mike D.; Jones, William T.; Sleight, David W.; Chun, Julio; Spangler, Jan L.; Kamhawi, Hilmi; Dahl, Jorgen L.

    2006-01-01

    This paper describes initial progress towards the development and enhancement of a set of software tools for rapid adaptive modeling, and conceptual design of advanced aerospace vehicle concepts. With demanding structural and aerodynamic performance requirements, these high fidelity geometry based modeling tools are essential for rapid and accurate engineering analysis at the early concept development stage. This adaptive modeling tool was used for generating vehicle parametric geometry, outer mold line and detailed internal structural layout of wing, fuselage, skin, spars, ribs, control surfaces, frames, bulkheads, floors, etc., that facilitated rapid finite element analysis, sizing study and weight optimization. The high quality outer mold line enabled rapid aerodynamic analysis in order to provide reliable design data at critical flight conditions. Example application for structural design of a conventional aircraft and a high altitude long endurance vehicle configuration are presented. This work was performed under the Conceptual Design Shop sub-project within the Efficient Aerodynamic Shape and Integration project, under the former Vehicle Systems Program. The project objective was to design and assess unconventional atmospheric vehicle concepts efficiently and confidently. The implementation may also dramatically facilitate physics-based systems analysis for the NASA Fundamental Aeronautics Mission. In addition to providing technology for design and development of unconventional aircraft, the techniques for generation of accurate geometry and internal sub-structure and the automated interface with the high fidelity analysis codes could also be applied towards the design of vehicles for the NASA Exploration and Space Science Mission projects.

  3. Sandia Advanced MEMS Design Tools, Version 2.0

    2002-06-13

    Sandia Advanced MEMS Design Tools is a 5-level surface micromachine fabrication technology, which customers internal and external to Sandia can access to fabricate prototype MEMS devices. This CD contains an integrated set of electronic files that: a) Describe the SUMMiT V fabrication process b) Provide enabling educational information (including pictures, videos, technical information) c)Facilitate the process of designing MEMS with the SUMMiT process (prototype file, Design Rule Checker, Standard Parts Library) d) Facilitate the processmore » of having MEMS fabricated at SNL e) Facilitate the process of having post-fabrication services performed While there exist some files on the CD that are used in conjunction with the software AutoCAD, these files are not intended for use independent of the CD. NOTE: THE CUSTOMER MUST PURCHASE HIS/HER OWN COPY OF AutoCAD TO USE WITH THESE FILES.« less

  4. Advanced Wet Tantalum Capacitors: Design, Specifications and Performance

    NASA Technical Reports Server (NTRS)

    Teverovsky, Alexander

    2016-01-01

    Insertion of new types of commercial, high volumetric efficiency wet tantalum capacitors in space systems requires reassessment of the existing quality assurance approaches that have been developed for capacitors manufactured to MIL-PRF-39006 requirements. The specifics of wet electrolytic capacitors is that leakage currents flowing through electrolyte can cause gas generation resulting in building up of internal gas pressure and rupture of the case. The risk associated with excessive leakage currents and increased pressure is greater for high value advanced wet tantalum capacitors, but it has not been properly evaluated yet. This presentation gives a review of specifics of the design, performance, and potential reliability risks associated with advanced wet tantalum capacitors. Problems related to setting adequate requirements for DPA, leakage currents, hermeticity, stability at low and high temperatures, ripple currents for parts operating in vacuum, and random vibration testing are discussed. Recommendations for screening and qualification to reduce risks of failures have been suggested.

  5. Recent advances in cardiac SPECT instrumentation and system design.

    PubMed

    Smith, Mark F

    2013-08-01

    Recent advances in clinical cardiac SPECT instrumentation are reviewed from a systems perspective. New hardware technologies include pixelated scintillator and semiconductor detector elements; photodetectors such as position-sensitive photomultiplier tubes (PSPMT), avalanche photodiodes (APD) and silicon photomultipliers (SiPM); and novel cardiac collimation methods. There are new approaches for positioning detectors and controlling their motion during cardiac imaging. Software technology advances include iterative image reconstruction with modeling of Poisson statistics and depth-dependent collimator response. These new technologies enable faster acquisitions, the lowering of administered activity and radiation dose, and improved image resolution. Higher sensitivity collimators are a significant factor enabling faster acquisitions. Several clinical systems incorporating new technologies are discussed and different system designs can achieve similar performance. With detector elements such as APDs, SiPMs and semiconductors that are insensitive to magnetic fields, the potential for cardiac SPECT imagers that are MRI compatible opens up new frontiers in clinical cardiac research and patient care. PMID:23832650

  6. On-Line NDE for Advanced Reactor Designs

    NASA Astrophysics Data System (ADS)

    Nakagawa, N.; Inanc, F.; Thompson, R. B.; Junker, W. R.; Ruddy, F. H.; Beatty, J. M.; Arlia, N. G.

    2003-03-01

    This expository paper introduces the concept of on-line sensor methodologies for monitoring the integrity of components in next generation power systems, and explains general benefits of the approach, while describing early conceptual developments of suitable NDE methodologies. The paper first explains the philosophy behind this approach (i.e. the design-for-inspectability concept). Specifically, we describe where and how decades of accumulated knowledge and experience in nuclear power system maintenance are utilized in Generation IV power system designs, as the designs are being actively developed, in order to advance their safety and economy. Second, we explain that Generation IV reactor design features call for the replacement of the current outage-based maintenance by on-line inspection and monitoring. Third, the model-based approach toward design and performance optimization of on-line sensor systems, using electromagnetic, ultrasonic, and radiation detectors, will be explained. Fourth, general types of NDE inspections that are considered amenable to on-line health monitoring will be listed. Fifth, we will describe specific modeling developments to be used for radiography, EMAT UT, and EC detector design studies.

  7. Advanced Space Suit Portable Life Support Subsystem Packaging Design

    NASA Technical Reports Server (NTRS)

    Howe, Robert; Diep, Chuong; Barnett, Bob; Thomas, Gretchen; Rouen, Michael; Kobus, Jack

    2006-01-01

    This paper discusses the Portable Life Support Subsystem (PLSS) packaging design work done by the NASA and Hamilton Sundstrand in support of the 3 future space missions; Lunar, Mars and zero-g. The goal is to seek ways to reduce the weight of PLSS packaging, and at the same time, develop a packaging scheme that would make PLSS technology changes less costly than the current packaging methods. This study builds on the results of NASA s in-house 1998 study, which resulted in the "Flex PLSS" concept. For this study the present EMU schematic (low earth orbit) was used so that the work team could concentrate on the packaging. The Flex PLSS packaging is required to: protect, connect, and hold the PLSS and its components together internally and externally while providing access to PLSS components internally for maintenance and for technology change without extensive redesign impact. The goal of this study was two fold: 1. Bring the advanced space suit integrated Flex PLSS concept from its current state of development to a preliminary design level and build a proof of concept mockup of the proposed design, and; 2. "Design" a Design Process, which accommodates both the initial Flex PLSS design and the package modifications, required to accommodate new technology.

  8. Co-Simulation for Advanced Process Design and Optimization

    SciTech Connect

    Stephen E. Zitney

    2009-01-01

    Meeting the increasing demand for clean, affordable, and secure energy is arguably the most important challenge facing the world today. Fossil fuels can play a central role in a portfolio of carbon-neutral energy options provided CO{sub 2} emissions can be dramatically reduced by capturing CO{sub 2} and storing it safely and effectively. Fossil energy industry faces the challenge of meeting aggressive design goals for next-generation power plants with CCS. Process designs will involve large, highly-integrated, and multipurpose systems with advanced equipment items with complex geometries and multiphysics. APECS is enabling software to facilitate effective integration, solution, and analysis of high-fidelity process/equipment (CFD) co-simulations. APECS helps to optimize fluid flow and related phenomena that impact overall power plant performance. APECS offers many advanced capabilities including ROMs, design optimization, parallel execution, stochastic analysis, and virtual plant co-simulations. NETL and its collaborative R&D partners are using APECS to reduce the time, cost, and technical risk of developing high-efficiency, zero-emission power plants with CCS.

  9. Advanced integrated spectrometer designs for miniaturized optical coherence tomography systems

    NASA Astrophysics Data System (ADS)

    Akca, B. I.; Považay, B.; Chang, L.; Alex, A.; Wörhoff, K.; de Ridder, R. M.; Drexler, W.; Pollnau, M.

    2013-06-01

    Optical coherence tomography (OCT) has enabled clinical applications that revolutionized in vivo medical diagnostics. Nevertheless, its current limitations owing to cost, size, complexity, and the need for accurate alignment must be overcome by radically novel approaches. Exploiting integrated optics, the central components of a spectral-domain OCT (SD-OCT) system can be integrated on a chip. Arrayed-waveguide grating (AWG) spectrometers with their high spectral resolution and compactness are excellent candidates for on-chip SD-OCT systems. However, specific design-related issues of AWG spectrometers limit the performance of on-chip SD-OCT systems. Here we present advanced AWG designs which could overcome the limitations arising from free spectral range, polarization dependency, and curved focal plane of the AWG spectrometers. Using these advanced AWG designs in an SD-OCT system can provide not only better overall performance but also some unique aspects that a commercial system does not have. Additionally, a partially integrated OCT system comprising an AWG spectrometer and an integrated beam splitter, as well as the in vivo imaging using this system are demonstrated.

  10. Low Conversion Loss Mixers with Improved Finline Transition and Bandstop Filter

    NASA Astrophysics Data System (ADS)

    Yao, Changfei; Xu, Jinping; Chen, Mo

    2009-03-01

    A Ka-Band hybrid integrated single-ended mixer with low conversion loss is designed in this paper. In the proposed circuit architecture, metallic via holes are implemented along the mounting edge of substrate embedded in the split-block of WG (waveguide)-finline-microstrip transition. Simulated results show that the effect of high-order modes due to the mounting groove is effectively eliminated and the transition loss is greatly improved. Meanwhile, a slow wave and bandstop filter at Ka band, which presents an equivalent short circuit, is designed for the maximized utilization of idle frequency energy, RF and LO signal energy. In this way, the conversion loss of the mixer can be further improved. The lowest measured conversion loss 3.52dB is obtained at 32.2 GHz; the conversion loss is flat and less than 5.68dB over the frequency band from 29 to 34 GHz.

  11. Advances in designs for Alzheimer’s disease clinical trials

    PubMed Central

    Cummings, Jeffrey; Gould, Heath; Zhong, Kate

    2012-01-01

    There is an urgent need to identify new treatments for the rapidly growing population of people with Alzheimer’s disease (AD). Innovations in clinical trial designs many help to reduce development time, provide more definitive answers regarding drug efficacy, and facilitate prioritizing compounds to be advanced to Phase III clinical trials. Standard designs compare drug and placebo changes from baseline on a rating scale. Baysian adaptive clinical trials allow the use of data collected in the trial to modify doses, sample size, trial duration, and entry criteria in an ongoing way as the data are collected. Disease-modification is supported by findings on staggered start and delayed withdrawal designs. Futility designs can use historical controls and may shorten trial duration. Combination therapy designs may allow investigation of additive or synergistic treatment effects. Novel trial selection criteria allow investigation of treatment effects in asymptomatic or minimally symptomatic, prodromal AD populations. The Clinical Dementia Rating-Sum of Boxes (CDR-SOB) can be considered as a single trial outcome in early disease populations. Alternate forms of the Alzheimer’s Disease Assessment Scale-Cognitive Portion (ADAS-cog), computerized measures, and pharmacoeconomic scales provide new and relevant information on drug effects. Comparative dose strategies are used in trials of symptomatic agents, and novel methods including withdrawal designs, symptom emergence analyses, and sequential designs are being utilized to assess the efficacy of putative psychotropic agents. The choice of trial design is driven by the question to be answered by the clinical trial; an increasing number of design approaches are available and may be useful in accelerating and refining AD drug development. PMID:23383393

  12. Advanced water window x-ray microscope design and analysis

    NASA Technical Reports Server (NTRS)

    Shealy, D. L.; Wang, C.; Jiang, W.; Lin, J.

    1992-01-01

    The project was focused on the design and analysis of an advanced water window soft-x-ray microscope. The activities were accomplished by completing three tasks contained in the statement of work of this contract. The new results confirm that in order to achieve resolutions greater than three times the wavelength of the incident radiation, it will be necessary to use aspherical mirror surfaces and to use graded multilayer coatings on the secondary (to accommodate the large variations of the angle of incidence over the secondary when operating the microscope at numerical apertures of 0.35 or greater). The results are included in a manuscript which is enclosed in the Appendix.

  13. Advanced Crew Interface Designs for Safer Air Travel

    NASA Technical Reports Server (NTRS)

    1998-01-01

    NASA is developing advanced crew interface designs to improve performance for safe air travel. NASA's goal is to provide enabling technologies that will increase aviation safety by a factor of five within 10 years, and by a factor of ten within 25 years. This research is part of NASA's Aeronautics and Space Transportation Technology (ASTT) Enterprise's strategy to sustain U.S. leadership in aeronautics and space. The Enterprise has set bold goals that are grouped into Three Pillars: Global Civil Aviation, Revolutionary Technology Leaps and Access to Space.

  14. Split-Waveguide Mounts For Submillimeter-Wave Multipliers And Harmonic Mixers

    NASA Technical Reports Server (NTRS)

    Raisanen, Antti; Choudhury, Debabani; Dengler, Robert J.; Oswald, John E.; Siegel, Peter H.

    1996-01-01

    Novel variation of split-waveguide mount for millimeter-and submillimeter-wavelength frequency multipliers and harmonic mixers developed. Designed to offer wide range of available matching impedances, while maintaining relatively simple fabrication sequence. Wide tuning range achieved with separate series and parallel elements, consisting of two pairs of noncontacting sliding backshorts, at fundamental and harmonic frequencies. Advantages include ease of fabrication, reliability, and tunability.

  15. Recent advances in the design of distributed embedded systems

    NASA Astrophysics Data System (ADS)

    Bay, John S.

    2002-08-01

    The network-centric 'system-of-systems' concept popular in current defense programs has been viewed from a very functional perspective. However, the heart of such a system is going to be an embedded software infrastructure of unprecedented complexity, and the technology for developing and testing this software needs as much if not more immediate attention than the concept of operations for the envisioned applications. Such an embedded software system will need to be infinitely scalable, modular, verifiable, and distributed, yet satisfy the myriad hard real-time performance constraints imposed by each of perhaps many different device types and service demands. It is suggested here that the only path to a robust design methodology for such systems is with model-based design. Model-based embedded system design is the focus of the Model-Based Integration of Embedded Software (MoBIES) program, currently underway at the Defense Advanced Research Projects Agency (DARPA), managed by the author. This paper will motivate the model-based approach to large-scale embedded software design and explain how projects funded under MoBIES are contributing to the development of interoperable model-based design tool components. An application for such technology is provided in the context of digital flight control systems for aggressive aircraft maneuvers, which is the subject of another DARPA sponsored program, Software-Enabled Control (SEC).

  16. Magnetic design of the advanced light source elliptical wiggler

    SciTech Connect

    Marks, S.; Akre, J.; Hoyer, E.; Humphries, D.; Jackson, T.; Minamihara, Y.; Pipersky, P.; Plate, D.; Schlueter, R.

    1995-06-01

    An elliptical wiggler has been designed for installation in the Advanced Light Source at the Lawrence Berkeley Laboratory. The design has been optimized for the production of circularly polarized light in the 50 eV to 10 KeV energy range. The device will be 3.4 m long consisting of vertical and horizontal periodic structures. The period length for both is 20 cm. The vertical structure is a hybrid permanent magnet design which produces a peak field of 2.0 T. The horizontal magnetic structure is an iron core electromagnetic design shifted longitudinally by one-quarter period relative to the vertical structure; it has a peak field of 0.095 T. The polarity of the horizontal field can be switched at a rate of up to 1 Hz, which results in a modulation of the chirality of the circularly polarized radiation on-axis. This paper discusses the magnetic design and presents the results of radiation spectra calculations used for determining optimal field parameter settings.

  17. Design Advances in Particulate Systems for Biomedical Applications.

    PubMed

    Lima, Ana Catarina; Alvarez-Lorenzo, Carmen; Mano, João F

    2016-07-01

    The search for more efficient therapeutic strategies and diagnosis tools is a continuous challenge. Advances in understanding the biological mechanisms behind diseases and tissues regeneration have widened the field of applications of particulate systems. Particles are no more just protective systems for the encapsulated drugs, but they play an active role in the success of the therapy. Moreover, particles have been explored for innovative purposes as templates for cells growth and as diagnostic tools. Until few years ago the most relevant parameters in particles formulation were the chemistry and the size. Currently, it is known that other physical characteristics can remarkably affect the performance of particulate systems. Particles with non-conventional shapes exhibit advantages due to the increasing circulation time in blood stream, less clearance by the immune system and more efficient cell internalization and trafficking. Creation of compartments has been found useful to control drug release, to tune the transport of substances across biological barriers, to supply the target with more than one bioactive agent or even to act as theranostic systems. It is expected that such complex shaped and compartmentalized systems improve the therapeutic outcomes and also the patient's compliance, acting as advanced devices that serve for simultaneous diagnosis and treatment of the disease, combining agents of very different features, at the same time. In this review, we overview and analyse the most recent advances in particle shape and compartmentalization and applications of newly designed particulate systems in the biomedical field. PMID:27332041

  18. Turbofan forced mixer-nozzle internal flowfield. Volume 3: A computer code for 3-D mixing in axisymmetric nozzles

    NASA Technical Reports Server (NTRS)

    Kreskovsky, J. P.; Briley, W. R.; Mcdonald, H.

    1982-01-01

    A finite difference method is developed for making detailed predictions of three dimensional subsonic turbulent flow in turbofan lobe mixers. The governing equations are solved by a forward-marching solution procedure which corrects an inviscid potential flow solution for viscous and thermal effects, secondary flows, total pressure distortion and losses, internal flow blockage and pressure drop. Test calculations for a turbulent coaxial jet flow verify that the turbulence model performs satisfactorily for this relatively simple flow. Lobe mixer flows are presented for two geometries typical of current mixer design. These calculations included both hot and cold flow conditions, and both matched and mismatched Mach number and total pressure in the fan and turbine streams.

  19. ELECTROMAGNETISM, OPTICS, ACOUSTICS, HEAT TRANSFER, CLASSICAL MECHANICS, AND FLUID DYNAMICS: Effect of Viscosities on Mixing in A Patterned Micro Mixer

    NASA Astrophysics Data System (ADS)

    Hua, Shuo; Liu, Yang; Xu, You-Sheng

    2010-05-01

    The effect of viscosity and viscosity difference and boundary patterned slip on mixing in a micro mixer has been numerically studied using lattice Boltzmann method (LBM). The slip and no-slip ratio is not constant and varies irregularly, and viscosity is altered by changing the relaxation time in LBE equation. The slip boundary condition is simulated by specular reflection boundary and the no-slip boundary condition is simulated by bounce back boundary. It has been found that it is feasible to optimize the micro mixer design by combining the viscosity effect and boundary patterned ratio altogether.

  20. Demonstration of An Image Rejection Mixer for High Frequency Applications (26-36 GHz)

    NASA Technical Reports Server (NTRS)

    Bankston, Cheryl D.; Carlstrom, John E.

    1999-01-01

    A new high frequency image-rejection mixer was successfully tested in a 26-36 GHz band receiver. This paper briefly describes the motivation for implementation of an image rejection mixer in a receiver system, the basic operation of an image rejection mixer, and the development and testing of an image rejection mixer for a high frequency, cryogenic receiver system.

  1. Systems analysis and futuristic designs of advanced biofuel factory concepts.

    SciTech Connect

    Chianelli, Russ; Leathers, James; Thoma, Steven George; Celina, Mathias Christopher; Gupta, Vipin P.

    2007-10-01

    The U.S. is addicted to petroleum--a dependency that periodically shocks the economy, compromises national security, and adversely affects the environment. If liquid fuels remain the main energy source for U.S. transportation for the foreseeable future, the system solution is the production of new liquid fuels that can directly displace diesel and gasoline. This study focuses on advanced concepts for biofuel factory production, describing three design concepts: biopetroleum, biodiesel, and higher alcohols. A general schematic is illustrated for each concept with technical description and analysis for each factory design. Looking beyond current biofuel pursuits by industry, this study explores unconventional feedstocks (e.g., extremophiles), out-of-favor reaction processes (e.g., radiation-induced catalytic cracking), and production of new fuel sources traditionally deemed undesirable (e.g., fusel oils). These concepts lay the foundation and path for future basic science and applied engineering to displace petroleum as a transportation energy source for good.

  2. Conceptual design of the advanced marine reactor MRX

    NASA Astrophysics Data System (ADS)

    1991-02-01

    Design studies on the advanced marine reactors have been done continuously since 1983 at the Japan Atomic Energy Research Institute (JAERI) in order to develop attractive marine reactors for the next generation. At present, two marine reactor concepts are being formulated. One is 100 MWt MRX (Marine Reactor X) for an icebreaker and the other is 300 kWe DRX (Deep-sea Reactor X) for a deep-sea research vessel. They are characterized by an integral type pressurized water reactor (PWR) built-in type control rod drive mechanisms, a water-filled container and a passive decay heat removal system, which realize highly passive safe and compact reactors. This paper is a detailed report including all major results of the MRX design study.

  3. Optimal design application on the advanced aeroelastic rotor blade

    NASA Technical Reports Server (NTRS)

    Wei, F. S.; Jones, R.

    1985-01-01

    The vibration and performance optimization procedure using regression analysis was successfully applied to an advanced aeroelastic blade design study. The major advantage of this regression technique is that multiple optimizations can be performed to evaluate the effects of various objective functions and constraint functions. The data bases obtained from the rotorcraft flight simulation program C81 and Myklestad mode shape program are analytically determined as a function of each design variable. This approach has been verified for various blade radial ballast weight locations and blade planforms. This method can also be utilized to ascertain the effect of a particular cost function which is composed of several objective functions with different weighting factors for various mission requirements without any additional effort.

  4. Large-Scale Advanced Prop-Fan (LAP) blade design

    NASA Technical Reports Server (NTRS)

    Violette, John A.; Sullivan, William E.; Turnberg, Jay E.

    1984-01-01

    This report covers the design analysis of a very thin, highly swept, propeller blade to be used in the Large-Scale Advanced Prop-Fan (LAP) test program. The report includes: design requirements and goals, a description of the blade configuration which meets requirements, a description of the analytical methods utilized/developed to demonstrate compliance with the requirements, and the results of these analyses. The methods described include: finite element modeling, predicted aerodynamic loads and their application to the blade, steady state and vibratory response analyses, blade resonant frequencies and mode shapes, bird impact analysis, and predictions of stalled and unstalled flutter phenomena. Summarized results include deflections, retention loads, stress/strength comparisons, foreign object damage resistance, resonant frequencies and critical speed margins, resonant vibratory mode shapes, calculated boundaries of stalled and unstalled flutter, and aerodynamic and acoustic performance calculations.

  5. Mixer pump test plan for double shell tank AZ-101

    SciTech Connect

    Symons, G.A.; Staehr, T.W., Westinghouse Hanford

    1996-06-01

    Westinghouse Hanford Company has undertaken the task to develop and demonstrate a method of retrieval for double-shell tank (DST)waste. Mixer pumps were chosen as the planned method of retrieval for the DSTs, based on engineering technology studies,past experience with hydraulic sluicing at the Hanford Site, and experience with mixer pumps at the Westinghouse Savannah River Site. This document outlines a test plan to demonstrate the ability of two 300 hp mixer pumps installed in the AZ-101 tank to mobilize waste.

  6. Development of Submillimeter SIS Mixers and Broadband HEMT Amplifiers

    NASA Technical Reports Server (NTRS)

    Zmuidzinas, Jonas

    2002-01-01

    The goal of this project is to develop and demonstrate a new generation of superconducting tunnel junction (SIS) receivers with extremely wide instantaneous (intermediate-frequency, or IF) bandwidths, of order 12 GHz. Such mixers would allow rapid submillimeter wavelength spectral line surveys to be carried out with SOFIA, and could potentially be used for future submillimeter space missions such as SAFIR. There are two major components which are being developed: (1) SIS mixers with broad (12 GHz) IF bandwidths; and (2) low-noise, broadband microwave, (6-18 GHz) amplifiers, which amplify the IF output from the SIS mixer. The work on these components is discussed in two sections

  7. Quadrature Mixer LO Leakage Suppression Through Quadrature DC Bias

    SciTech Connect

    BALDWIN, JESSE G; DUBBERT, DALE F.

    2002-05-01

    A new concept has been developed which allows direct-to-RF conversion of digitally synthesized waveforms. The concept named Quadrature Error Corrected Digital Waveform Synthesis (QECDWS) employs quadrature amplitude and phase predistortion to the complex waveform to reduce the undesirable quadrature image. Another undesirable product of QECDWS-based RF conversion is the Local Oscillator (LO) leakage through the quadrature upconverter (mixer). A common technique for reducing this LO leakage is to apply a quadrature bias to the mixer I and Q inputs. This report analyzes this technique through theory, lab measurement, and data analysis for a candidate quadrature mixer for Synthetic Aperture Radar (SAR) applications.

  8. Optimizing advanced propeller designs by simultaneously updating flow variables and design parameters

    NASA Technical Reports Server (NTRS)

    Rizk, Magdi H.

    1988-01-01

    A scheme is developed for solving constrained optimization problems in which the objective function and the constraint function are dependent on the solution of the nonlinear flow equations. The scheme updates the design parameter iterative solutions and the flow variable iterative solutions simultaneously. It is applied to an advanced propeller design problem with the Euler equations used as the flow governing equations. The scheme's accuracy, efficiency and sensitivity to the computational parameters are tested.

  9. Aerodynamic optimization by simultaneously updating flow variables and design parameters with application to advanced propeller designs

    NASA Technical Reports Server (NTRS)

    Rizk, Magdi H.

    1988-01-01

    A scheme is developed for solving constrained optimization problems in which the objective function and the constraint function are dependent on the solution of the nonlinear flow equations. The scheme updates the design parameter iterative solutions and the flow variable iterative solutions simultaneously. It is applied to an advanced propeller design problem with the Euler equations used as the flow governing equations. The scheme's accuracy, efficiency and sensitivity to the computational parameters are tested.

  10. Design of the Advanced Gas Reactor Fuel Experiments for Irradiation in the Advanced Test Reactor

    SciTech Connect

    S. Blaine Grover

    2005-10-01

    The United States Department of Energy’s Advanced Gas Reactor (AGR) Fuel Development and Qualification Program will be irradiating eight particle fuel tests in the Advanced Test Reactor (ATR) located at the newly formed Idaho National Laboratory (INL) to support development of the next generation Very High Temperature Reactor (VHTR) in the United States. The ATR has a long history of irradiation testing in support of reactor development and the INL has been designated as the new United States Department of Energy’s lead laboratory for nuclear energy development. These AGR fuel experiments will be irradiated over the next ten years to demonstrate and qualify new particle fuel for use in high temperature gas reactors. The experiments will be irradiated in an inert sweep gas atmosphere with on-line temperature monitoring and control combined with on-line fission product monitoring of the sweep gas. The final design phase has just been completed on the first experiment (AGR-1) in this series and the support systems and fission product monitoring system that will monitor and control the experiment during irradiation. This paper discusses the development of the experimental hardware and support system designs and the status of the experiment.

  11. Designing for safety in the conceptual design of the Advanced Neutron Source

    SciTech Connect

    Harrington, R.M.; West, C.D.

    1993-06-01

    The Advanced Neutron Source is a major new research facility proposed by the Department of Energy for construction over the next six years. The unique set of nuclear safety features selected to give the recently completed conceptual design a high degree of safety are identified and discussed.

  12. Evaluation of static mixer flow enhancements for cryogenic viscous compressor prototype for ITER vacuum system

    SciTech Connect

    Duckworth, Robert C.; Baylor, Larry R.; Meitner, Steven J.; Combs, Stephen K.; Ha, Tam; Morrow, Michael; Biewer, T.; Rasmussen, David A.; Hechler, Michael P.; Pearce, Robert J. H.; Dremel, Mattias; Boissin, J.-C.

    2014-01-29

    As part of the U.S. ITER contribution to the vacuum systems for the ITER fusion project, a cryogenic viscous compressor (CVC) is being designed and fabricated to cryopump hydrogenic gases in the torus and neutral beam exhaust streams and to regenerate the collected gases to controlled pressures such that they can be mechanically pumped with controlled flows to the tritium reprocessing facility. One critical element of the CVC design that required additional investigation was the determination of flow rates of the low pressure (up to 1000 Pa) exhaust stream that would allow for complete pumping of hydrogenic gases while permitting trace levels of helium to pass through the CVC to be pumped by conventional vacuum pumps. A sub-scale prototype test facility was utilized to determine the effectiveness of a static mixer pump tube concept, which consisted of a series of rotated twisted elements brazed into a 2-mm thick, 5-cm diameter stainless steel tube. Cold helium gas flow provided by a dewar and helium transfer line was used to cool the exterior of the static mixer pump tube. Deuterium gas was mixed with helium gas through flow controllers at different concentrations while the composition of the exhaust gas was monitored with a Penning gauge and optical spectrometer to determine the effectiveness of the static mixer. It was found that with tube wall temperatures between 6 K and 9 K, the deuterium gas was completely cryopumped and only helium passed through the tube. These results have been used to design the cooling geometry and the static mixer pump tubes in the full-scale CVC prototype.

  13. Evaluation of Static Mixer Flow Enhancements for Cryogenic Viscous Compressor Prototype for ITER Vacuum System

    SciTech Connect

    Duckworth, Robert C; Baylor, Larry R; Meitner, Steven J; Combs, Stephen Kirk; Ha, Tam T; Morrow, Michael; Biewer, Theodore M; Rasmussen, David A; Hechler, Michael P; Pearce, R.J.H.; Dremel, M.; Boissin, Jean Claude

    2014-01-01

    As part of the U.S. ITER contribution to the vacuum systems for the ITER fusion project, a cryogenic viscous compressor (CVC) is being designed and fabricated to cryopump hydrogenic gases in the torus and neutral beam exhaust streams and to regenerate the collected gases to controlled pressures such that they can be mechanically pumped with controlled flows to the tritium reprocessing facility. One critical element of the CVC design that required additional investigation was the determination of flow rates of the low pressure (50 to 1000 Pa) exhaust stream that would allow for complete pumping of hydrogenic gases while permitting trace levels of helium to pass through the CVC to be pumped by conventional vacuum pumps. A sub-scale prototype test facility was utilized to determine the effectiveness of a static mixer pump tube concept, which consisted of a series of rotated twisted elements brazed into a 2-mm thick, 5-cm diameter stainless steel tube. Cold helium gas flow provided by a dewar and helium transfer line was used to cool the exterior of the static mixer pump tube. Deuterium gas was mixed with helium gas through flow controllers at different concentrations while the composition of the exhaust gas was monitored with a Penning gauge and optical spectrometer to determine the effectiveness of the static mixer. It was found that with tube wall temperatures between 6 K and 9 K, the deuterium gas was completely cryopumped and only helium passed through the tube. These results have been used to design the cooling geometry and the static mixer pump tubes in the full-scale CVC prototype

  14. Evaluation of static mixer flow enhancements for cryogenic viscous compressor prototype for ITER vacuum system

    NASA Astrophysics Data System (ADS)

    Duckworth, Robert C.; Baylor, Larry R.; Meitner, Steven J.; Combs, Stephen K.; Ha, Tam; Morrow, Michael; Biewer, T.; Rasmussen, David A.; Hechler, Michael P.; Pearce, Robert J. H.; Dremel, Mattias; Boissin, J.-C.

    2014-01-01

    As part of the U.S. ITER contribution to the vacuum systems for the ITER fusion project, a cryogenic viscous compressor (CVC) is being designed and fabricated to cryopump hydrogenic gases in the torus and neutral beam exhaust streams and to regenerate the collected gases to controlled pressures such that they can be mechanically pumped with controlled flows to the tritium reprocessing facility. One critical element of the CVC design that required additional investigation was the determination of flow rates of the low pressure (up to 1000 Pa) exhaust stream that would allow for complete pumping of hydrogenic gases while permitting trace levels of helium to pass through the CVC to be pumped by conventional vacuum pumps. A sub-scale prototype test facility was utilized to determine the effectiveness of a static mixer pump tube concept, which consisted of a series of rotated twisted elements brazed into a 2-mm thick, 5-cm diameter stainless steel tube. Cold helium gas flow provided by a dewar and helium transfer line was used to cool the exterior of the static mixer pump tube. Deuterium gas was mixed with helium gas through flow controllers at different concentrations while the composition of the exhaust gas was monitored with a Penning gauge and optical spectrometer to determine the effectiveness of the static mixer. It was found that with tube wall temperatures between 6 K and 9 K, the deuterium gas was completely cryopumped and only helium passed through the tube. These results have been used to design the cooling geometry and the static mixer pump tubes in the full-scale CVC prototype.

  15. Micromechanics Based Design/Analysis Codes for Advanced Composites

    NASA Technical Reports Server (NTRS)

    Mital, Subodh K.; Murthy, Pappu L. N.; Gyekenyesi, John P.

    2002-01-01

    Advanced high temperature Ceramic Matrix Composites (CMC) hold an enormous potential for use in aero and space related applications specifically for propulsion system components. Consequently, this has led to a multitude of research activities pertaining to fabrication, testing and modeling of these materials. The efforts directed at the development of ceramic matrix composites have focused primarily on improving the properties of the constituents as individual phases. It has, however, become increasingly clear that for CMC to be successfully employed in high temperature applications, research and development efforts should also focus on optimizing the synergistic performance of the constituent phases within the as-produced microstructure of the complex shaped CMC part. Despite their attractive features, the introduction of these materials in a wide spectrum of applications has been excruciatingly slow. The reasons are the high costs associated with the manufacturing and a complete experimental testing and characterization of these materials. Often designers/analysts do not have a consistent set of necessary properties and design allowables to be able to confidently design and analyze structural components made from these composites. Furthermore, the anisotropy of these materials accentuates the burden both on the test engineers and the designers by requiring a vastly increased amount of data/characterization compared to conventional materials.

  16. Design of Test Support Hardware for Advanced Space Suits

    NASA Technical Reports Server (NTRS)

    Watters, Jeffrey A.; Rhodes, Richard

    2013-01-01

    As a member of the Space Suit Assembly Development Engineering Team, I designed and built test equipment systems to support the development of the next generation of advanced space suits. During space suit testing it is critical to supply the subject with two functions: (1) cooling to remove metabolic heat, and (2) breathing air to pressurize the space suit. The objective of my first project was to design, build, and certify an improved Space Suit Cooling System for manned testing in a 1-G environment. This design had to be portable and supply a minimum cooling rate of 2500 BTU/hr. The Space Suit Cooling System is a robust, portable system that supports very high metabolic rates. It has a highly adjustable cool rate and is equipped with digital instrumentation to monitor the flowrate and critical temperatures. It can supply a variable water temperature down to 34 deg., and it can generate a maximum water flowrate of 2.5 LPM. My next project was to design and build a Breathing Air System that was capable of supply facility air to subjects wearing the Z-2 space suit. The system intakes 150 PSIG breathing air and regulates it to two operating pressures: 4.3 and 8.3 PSIG. It can also provide structural capabilities at 1.5x operating pressure: 6.6 and 13.2 PSIG, respectively. It has instrumentation to monitor flowrate, as well as inlet and outlet pressures. The system has a series of relief valves to fully protect itself in case of regulator failure. Both projects followed a similar design methodology. The first task was to perform research on existing concepts to develop a sufficient background knowledge. Then mathematical models were developed to size components and simulate system performance. Next, mechanical and electrical schematics were generated and presented at Design Reviews. After the systems were approved by the suit team, all the hardware components were specified and procured. The systems were then packaged, fabricated, and thoroughly tested. The next step

  17. HgCdTe Photoconductive Mixers for 2-8 THz

    NASA Technical Reports Server (NTRS)

    Betz, A. L.; Boreiko, R. T.; Sivananthan, S.; Ashokan, R.

    2001-01-01

    Heterodyne spectroscopy has been taken to wavelengths as short as 63 micrometers with Schottky-diode mixers. Schottkys, however, are relatively insensitive compared to superconducting mixers such as the hot-electron microbolometer (HEB), which has an effective quantum efficiency of 3% at 120 micrometers (2.5 THz). Although HEB sensitivities are bound to improve, there will always be losses associated with antenna coupling of radiation into sub-micron size devices. Another approach to far infrared (FIR) mixer design is to use a photoconductive device which can be made much larger than a wavelength, and thus act as its own antenna. For example, HgCdTe photodiodes have been used as mixers in the lambda = 10 micrometers band for over 25 years, with sensitivities now only a factor of 2 from the quantum-noise-limit. HgCdTe can also be applied at FIR wavelengths, but surprisingly little work has been done to date. The exception is the pioneering work of Spears and Kostiuk and Spears, who developed HgCdTe photomixers for the 20-120 micrometer region. The spectral versatility of the HgCdTe alloy is well recognized for wavelengths as long as 8-20 micrometers. What is not so recognized, however, is that theoretically there is no long wavelength limit for appropriately composited HgCdTe. Although Spears successfully demonstrated a photoconductive response from HgCdTe at 120 micrometers, this initial effort was apparently never followed up, in part because of the difficulty of controlling the HgCdTe alloy composition with liquid-phase-epitaxy (LPE) techniques. With the availability of precise molecular-beam-epitaxy (MBE) since the early 1990's, it is now appropriate to reconsider HgCdTe for detector applications longward of lambda = 20 micrometers. We recently initiated an effort to fabricate detectors and mixers using II-VI materials for FIR wavelengths. Of particular interest are device structures called superlattices, which offer a number of advantages for high sensitivity

  18. Interim Service ISDN Satellite (ISIS) hardware experiment design for advanced ISDN satellite design and experiments

    NASA Technical Reports Server (NTRS)

    Pepin, Gerard R.

    1992-01-01

    The Interim Service Integrated Services Digital Network (ISDN) Satellite (ISIS) Hardware Experiment Design for Advanced Satellite Designs describes the design of the ISDN Satellite Terminal Adapter (ISTA) capable of translating ISDN protocol traffic into time division multiple access (TDMA) signals for use by a communications satellite. The ISTA connects the Type 1 Network Termination (NT1) via the U-interface on the line termination side of the CPE to the V.35 interface for satellite uplink. The same ISTA converts in the opposite direction the V.35 to U-interface data with a simple switch setting.

  19. FRONT (SOUTH) ELEVATION, MIXER RUINS (CENTER) WITH STACKS (LEFT) AND ...

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

    FRONT (SOUTH) ELEVATION, MIXER RUINS (CENTER) WITH STACKS (LEFT) AND POWER HOUSE (RIGHT). - Tennessee Coal & Iron Company, Ensley Works, Open Hearth Furnace (Ruins), West of Ensley commercial & residential districts, Birmingham, Jefferson County, AL

  20. FRONT (SOUTH) ELEVATION, MIXER RUINS (CENTER) WITH STACKS (LEFT) AND ...

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

    FRONT (SOUTH) ELEVATION, MIXER RUINS (CENTER) WITH STACKS (LEFT) AND POWER HOUSE (RIGHT - Tennessee Coal & Iron Company, Ensley Works, Open Hearth Furnace (Ruins), West of Ensley commercial & residential districts, Birmingham, Jefferson County, AL

  1. 35. JL photographer, summer 1978, general view of chemical mixer ...

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

    35. JL photographer, summer 1978, general view of chemical mixer Baldwin Filtration plant - Division Avenue Pumping Station & Filtration Plant, West 45th Street and Division Avenue, Cleveland, Cuyahoga County, OH

  2. 41. JL photographer, summer 1978, view of chemical mixer from ...

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

    41. JL photographer, summer 1978, view of chemical mixer from atop chemical spray nozzels. - Division Avenue Pumping Station & Filtration Plant, West 45th Street and Division Avenue, Cleveland, Cuyahoga County, OH

  3. 47. Pouring deck columns, steampowered concrete mixer at center; direction ...

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

    47. Pouring deck columns, steam-powered concrete mixer at center; direction of view not clear, but probably to north. - Parks Bar Bridge, Spanning Yuba River at State Highway 20, Smartville, Yuba County, CA

  4. Sandia Advanced MEMS Design Tools, Version 2.2.5

    2010-01-19

    The Sandia National Laboratories Advanced MEMS Design Tools, Version 2.2.5, is a collection of menus, prototype drawings, and executables that provide significant productivity enhancements when using AutoCAD to design MEMS components. This release is designed for AutoCAD 2000i, 2002, or 2004 and is supported under Windows NT 4.0, Windows 2000, or XP. SUMMiT V (Sandia Ultra planar Multi level MEMS Technology) is a 5 level surface micromachine fabrication technology, which customers internal and external tomore » Sandia can access to fabricate prototype MEMS devices. This CD contains an integrated set of electronic files that: a) Describe the SUMMiT V fabrication process b) Facilitate the process of designing MEMS with the SUMMiT process (prototype file, Design Rule Checker, Standard Parts Library) New features in this version: AutoCAD 2004 support has been added. SafeExplode ? a new feature that explodes blocks without affecting polylines (avoids exploding polylines into objects that are ignored by the DRC and Visualization tools). Layer control menu ? a pull-down menu for selecting layers to isolate, freeze, or thaw. Updated tools: A check has been added to catch invalid block names. DRC features: Added username/password validation, added a method to update the user?s password. SNL_DRC_WIDTH ? a value to control the width of the DRC error lines. SNL_BIAS_VALUE ? a value use to offset selected geometry SNL_PROCESS_NAME ? a value to specify the process name Documentation changes: The documentation has been updated to include the new features. While there exist some files on the CD that are used in conjunction with software package AutoCAD, these files are not intended for use independent of the CD. Note that the customer must purchase his/her own copy of AutoCAD to use with these files.« less

  5. Sandia Advanced MEMS Design Tools, Version 2.2.5

    SciTech Connect

    Yarberry, Victor; Allen, James; Lantz, Jeffery; Priddy, Brian; & Westling, Belinda

    2010-01-19

    The Sandia National Laboratories Advanced MEMS Design Tools, Version 2.2.5, is a collection of menus, prototype drawings, and executables that provide significant productivity enhancements when using AutoCAD to design MEMS components. This release is designed for AutoCAD 2000i, 2002, or 2004 and is supported under Windows NT 4.0, Windows 2000, or XP. SUMMiT V (Sandia Ultra planar Multi level MEMS Technology) is a 5 level surface micromachine fabrication technology, which customers internal and external to Sandia can access to fabricate prototype MEMS devices. This CD contains an integrated set of electronic files that: a) Describe the SUMMiT V fabrication process b) Facilitate the process of designing MEMS with the SUMMiT process (prototype file, Design Rule Checker, Standard Parts Library) New features in this version: AutoCAD 2004 support has been added. SafeExplode ? a new feature that explodes blocks without affecting polylines (avoids exploding polylines into objects that are ignored by the DRC and Visualization tools). Layer control menu ? a pull-down menu for selecting layers to isolate, freeze, or thaw. Updated tools: A check has been added to catch invalid block names. DRC features: Added username/password validation, added a method to update the user?s password. SNL_DRC_WIDTH ? a value to control the width of the DRC error lines. SNL_BIAS_VALUE ? a value use to offset selected geometry SNL_PROCESS_NAME ? a value to specify the process name Documentation changes: The documentation has been updated to include the new features. While there exist some files on the CD that are used in conjunction with software package AutoCAD, these files are not intended for use independent of the CD. Note that the customer must purchase his/her own copy of AutoCAD to use with these files.

  6. Exploration of Advanced Probabilistic and Stochastic Design Methods

    NASA Technical Reports Server (NTRS)

    Mavris, Dimitri N.

    2003-01-01

    The primary objective of the three year research effort was to explore advanced, non-deterministic aerospace system design methods that may have relevance to designers and analysts. The research pursued emerging areas in design methodology and leverage current fundamental research in the area of design decision-making, probabilistic modeling, and optimization. The specific focus of the three year investigation was oriented toward methods to identify and analyze emerging aircraft technologies in a consistent and complete manner, and to explore means to make optimal decisions based on this knowledge in a probabilistic environment. The research efforts were classified into two main areas. First, Task A of the grant has had the objective of conducting research into the relative merits of possible approaches that account for both multiple criteria and uncertainty in design decision-making. In particular, in the final year of research, the focus was on the comparison and contrasting between three methods researched. Specifically, these three are the Joint Probabilistic Decision-Making (JPDM) technique, Physical Programming, and Dempster-Shafer (D-S) theory. The next element of the research, as contained in Task B, was focused upon exploration of the Technology Identification, Evaluation, and Selection (TIES) methodology developed at ASDL, especially with regards to identification of research needs in the baseline method through implementation exercises. The end result of Task B was the documentation of the evolution of the method with time and a technology transfer to the sponsor regarding the method, such that an initial capability for execution could be obtained by the sponsor. Specifically, the results of year 3 efforts were the creation of a detailed tutorial for implementing the TIES method. Within the tutorial package, templates and detailed examples were created for learning and understanding the details of each step. For both research tasks, sample files and

  7. An Advanced Tool for Control System Design and Maintenance

    SciTech Connect

    Storm, Joachim; Lohmann, Heinz

    2006-07-01

    The detailed engineering for control systems is usually supported by CAD Tools creating the relevant logic diagrams including software parameters and signal cross references. However at this stage of the design an early V and V process for checking out the functional correctness of the design is not available. The article describes the scope and capabilities of an advanced control system design tool which has the embedded capability of a stand-alone simulation of complex logic structures. The tool provides the following features for constructing logic diagrams for control systems: - Drag and Drop construction of logic diagrams using a predefined symbol sets; - Cross reference facility; - Data extraction facility; - Stand-alone simulation for Logic Diagrams featuring: On the fly changes, signal line animation, value boxes and mini trends etc. - Creation and on-line animation of Compound Objects (Handler); - Code Generation Facility for Simulation; - Code Generation Facility for several control systems. The results of the integrated simulation based V and V process can be used further for initial control system configuration and life cycle management as well as for Engineering Test Bed applications and finally in full Scope Replica Simulators for Operator Training. (authors)

  8. Automatic differentiation of advanced CFD codes for multidisciplinary design

    NASA Technical Reports Server (NTRS)

    Bischof, C.; Corliss, G.; Green, L.; Griewank, A.; Haigler, K.; Newman, P.

    1992-01-01

    Automated multidisciplinary design of aircraft and other flight vehicles requires the optimization of complex performance objectives with respect to a number of design parameters and constraints. The effect of these independent design variables on the system performance criteria can be quantified in terms of sensitivity derivatives which must be calculated and propagated by the individual discipline simulation codes. Typical advanced CFD analysis codes do not provide such derivatives as part of a flow solution; these derivatives are very expensive to obtain by divided (finite) differences from perturbed solutions. It is shown that sensitivity derivatives can be obtained accurately and efficiently using the ADIFOR source translator for automatic differentiation. In particular, it is demonstrated that the 3-D, thin-layer Navier-Stokes, multigrid flow solver called TLNS3D is amenable to automatic differentiation in the forward mode even with its implicit iterative solution algorithm and complex turbulence modeling. It is significant that by using computational differentiation, consistent discrete nongeometric sensitivity derivatives have been obtained from an aerodynamic 3-D CFD code in a relatively short time, e.g., O(man-week) not O(man-year).

  9. Advanced Silicon Solar Cell Device Physics and Design

    NASA Astrophysics Data System (ADS)

    Deceglie, Michael Gardner

    A fundamental challenge in the development and deployment of solar photovoltaic technology is a reduction in cost enabling direct competition with fossil-fuel-based energy sources. A key driver in this cost reduction is optimized device efficiency, because increased energy output leverages all photovoltaic system costs, from raw materials and module manufacturing to installation and maintenance. To continue progress toward higher conversion efficiencies, solar cells are being fabricated with increasingly complex designs, including engineered nanostructures, heterojunctions, and novel contacting and passivation schemes. Such advanced designs require a comprehensive and unified understanding of the optical and electrical device physics at the microscopic scale. This thesis focuses on a microscopic understanding of solar cell optoelectronic performance and its impact on cell optimization. We consider this in three solar cell platforms: thin-film crystalline silicon, amorphous/crystalline silicon heterojunctions, and thin-film cells with nanophotonic light trapping. The work described in this thesis represents a powerful design paradigm, based on a detailed physical understanding of the mechanisms governing solar cell performance. Furthermore, we demonstrate the importance of understanding not just the individual mechanisms, but also their interactions. Such an approach to device optimization is critical for the efficiency and competitiveness of future generations of solar cells.

  10. Design and development of advanced adaptive polymer lenses

    NASA Astrophysics Data System (ADS)

    Santiago, Freddie

    The dissertation presented here describes advancements made in adaptive polymer lens design and implementation. Singlets and doublets lenses were constructed for visible, short- wavelength infrared (SWIR), and middle-wavelength infrared (MWIR) applications. The lenses are implemented in a variety of tactical imaging systems to demonstrate their performance. A process was developed that defines the allowable fabrication variables, first for APL singlets and then for APL doublets. A first-order finite element model is described that enables going from an optical design to APL fabrication. This model was then extended to the design of fluidic doublets, which are equivalent to their two-element glass counter-parts. Two constant volume fluidic chambers were enclosed by three flexible membranes resulting in a variable focal length doublet. Chromatic focal shift was then used to compare numerical modeling to experimentally measured results. These same tools, methodology, and process were lastly used in the definition and fabrication of the SWIR and MWIR adaptive polymer lens for tactical systems. Imaging and illumination systems are presented, based on these lensesnotably an adaptive zoom imaging system, in the MWIR. This is the first known instance of such a system in this band.

  11. Design of advanced ultrasonic transducers for welding devices.

    PubMed

    Parrini, L

    2001-11-01

    A new high frequency ultrasonic transducer has been conceived, designed, prototyped, and tested. In the design phase, an advanced approach was used and established. The method is based on an initial design estimate obtained with finite element method (FEM) simulations. The simulated ultrasonic transducers and resonators are then built and characterized experimentally through laser interferometry and electrical resonance spectra. The comparison of simulation results with experimental data allows the parameters of FEM models to be adjusted and optimized. The achieved FEM simulations exhibit a remarkably high predictive potential and allow full control of the vibration behavior of the transducer. The new transducer is mounted on a wire bonder with a flange whose special geometry was calculated by means of FEM simulations. This flange allows the transducer to be attached on the wire bonder, not only in longitudinal nodes, but also in radial nodes of the ultrasonic field excited in the horn. This leads to a total decoupling of the transducer to the wire bonder, which has not been achieved so far. The new approach to mount ultrasonic transducers on a welding device is of major importance, not only for wire bonding, but also for all high power ultrasound applications and has been patented. PMID:11800125

  12. Aerospace Engineering Systems and the Advanced Design Technologies Testbed Experience

    NASA Technical Reports Server (NTRS)

    VanDalsem, William R.; Livingston, Mary E.; Melton, John E.; Torres, Francisco J.; Stremel, Paul M.

    1999-01-01

    Continuous improvement of aerospace product development processes is a driving requirement across much of the aerospace community. As up to 90% of the cost of an aerospace product is committed during the first 10% of the development cycle, there is a strong emphasis on capturing, creating, and communicating better information (both requirements and performance) early in the product development process. The community has responded by pursuing the development of computer-based systems designed to enhance the decision-making capabilities of product development individuals and teams. Recently, the historical foci on sharing the geometrical representation and on configuration management are being augmented: 1) Physics-based analysis tools for filling the design space database; 2) Distributed computational resources to reduce response time and cost; 3) Web-based technologies to relieve machine-dependence; and 4) Artificial intelligence technologies to accelerate processes and reduce process variability. The Advanced Design Technologies Testbed (ADTT) activity at NASA Ames Research Center was initiated to study the strengths and weaknesses of the technologies supporting each of these trends, as well as the overall impact of the combination of these trends on a product development event. Lessons learned and recommendations for future activities are reported.

  13. Conceptual design of a solar electric advanced Stirling power system

    NASA Astrophysics Data System (ADS)

    White, M. A.; Brown, A. T.

    1987-02-01

    The objective is to develop a high confidence conceptual design for a free-piston Stirling engine based system designed to deliver 25 kW of three-phase electric power to a utility grid when coupled to the 11 meter Test Bed Concentrator (TBC) at SNLA. Further objectives include a design life of 60,000 hours, minimum life cycle cost and dynamic balancing. The approach used to achieve these objectives is to utilize a hermetically sealed Stirling hydraulic concept based on technology developed to an advanced level during the past 19 years for an artificial heart power source. Such engines and critical metal bellows components have demonstrated operating times in the desired range. This approach provides full film hydraulic lubrication of all sliding parts, simple construction with conventional manufacturing tolerances, proven hydraulically coupled counterbalancing, and simple but effective power control to follow insolation variations. Other advantages include use of commercially available hydraulic motors and rotary alternators which can be placed on the ground to minimize suspended weight. The output from several engine/concentrator modules can be directed to one large motor/alternator for further cost savings. Three monthly progress reports for the same period, January 1 to January 31, 1987, are compiled within this document.

  14. Core design studies for advanced burner test reactor.

    SciTech Connect

    Yang, W. S.; Kim, T. K.; Hill, R. N.; Nuclear Engineering Division

    2008-01-01

    The U.S. government announced in February 2006 the Global Nuclear Energy Partnership (GNEP) to expand the use of nuclear energy to meet increasing global energy demand, to address nuclear waste management concerns and to promote non-proliferation. The advanced burner reactor (ABR) based on a fast spectrum is one of the three major technologies to be demonstrated in GNEP. In FY06, a pre-conceptual design study was performed to develop an advanced burner test reactor (ABTR) that supports development of a prototype full-scale ABR, which would be followed by commercial deployment of ABRs. The primary objectives of the ABTR were (1) to demonstrate reactor-based transmutation of transuranics (TRU) as part of an advanced fuel cycle, (2) to qualify the TRU-containing fuels and advanced structural materials needed for a full-scale ABR, (3) to support the research, development and demonstration required for certification of an ABR standard design by the U.S. Nuclear Regulatory Commission. Based on these objectives, core design and fuel cycle studies were performed to develop ABTR core designs, which can accommodate the expected changes of the TRU feed and the conversion ratio. Various option and trade-off studies were performed to determine the appropriate power level and conversion ratio. Both ternary metal alloy (U-TRU-10Zr) and mixed oxide (UO{sub 2}-TRUO{sub 2}) fuel forms have been considered with TRU feeds from weapons-grade plutonium (WG-Pu) and TRU recovered from light water reactor spent fuel (LWR-SF). Reactor performances were evaluated in detail including equilibrium cycle core parameters, mass flow, power distribution, kinetic parameters, reactivity feedback coefficient, reactivity control requirements and shutdown margins, and spent fuel characteristics. Trade-off studies on power level suggested that about 250 MWt is a reasonable compromise to allow a low project cost, at the same time providing a reasonable prototypic irradiation environment for demonstrating

  15. Automatic differentiation of advanced CFD codes for multidisciplinary design

    SciTech Connect

    Bischof, C.; Corliss, G.; Griewank, A. ); Green, L.; Haigler, K.; Newman, P. . Langley Research Center)

    1992-01-01

    Automated multidisciplinary design of aircraft and other flight vehicles requires the optimization of complex performance objectives with respect to a number of design parameters and constraints. The effect of these independent design variables on the system performance criteria can be quantified in terms of sensitivity derivatives which must be calculated and propagated by the individual discipline simulation codes. Typical advanced CFD analysis codes do not provide such derivatives as part of a flow solution; these derivatives are very expensive to obtain by divided (finite) differences from perturbed solutions. It is shown here that sensitivity derivatives can be obtained accurately and efficiently using the ADIFOR source translator for automatic differentiation. In particular, it is demonstrated that the 3-D, thin-layer Navier-Stokes, multigrid flow solver called TLNS3D is amenable to automatic differentiation in the forward mode even with its implicit iterative solution algorithm and complex turbulence modeling. It is significant that using computational differentiation, consistent discrete nongeometric sensitivity derivatives have been obtained from an aerodynamic 3-D CFD code in a relatively short time, e.g. O(man-week) not O(man-year).

  16. Automatic differentiation of advanced CFD codes for multidisciplinary design

    SciTech Connect

    Bischof, C.; Corliss, G.; Griewank, A.; Green, L.; Haigler, K.; Newman, P.

    1992-12-31

    Automated multidisciplinary design of aircraft and other flight vehicles requires the optimization of complex performance objectives with respect to a number of design parameters and constraints. The effect of these independent design variables on the system performance criteria can be quantified in terms of sensitivity derivatives which must be calculated and propagated by the individual discipline simulation codes. Typical advanced CFD analysis codes do not provide such derivatives as part of a flow solution; these derivatives are very expensive to obtain by divided (finite) differences from perturbed solutions. It is shown here that sensitivity derivatives can be obtained accurately and efficiently using the ADIFOR source translator for automatic differentiation. In particular, it is demonstrated that the 3-D, thin-layer Navier-Stokes, multigrid flow solver called TLNS3D is amenable to automatic differentiation in the forward mode even with its implicit iterative solution algorithm and complex turbulence modeling. It is significant that using computational differentiation, consistent discrete nongeometric sensitivity derivatives have been obtained from an aerodynamic 3-D CFD code in a relatively short time, e.g. O(man-week) not O(man-year).

  17. Design related aspects in advanced nuclear fission plants

    NASA Astrophysics Data System (ADS)

    Hoffelner, Wolfgang

    2011-02-01

    Important issues to be considered for design of future reactors are: extrapolation of stress rupture data, creep-fatigue, negligible creep, damage monitoring. The paper highlights some new developments taking examples from a martensitic steel (mod 9% Cr), oxide dispersion strengthened (ODS) steels and nickel-base superalloys. Traditional approaches to extrapolation of (thermal) stress rupture data like Larson-Miller Parameter or Monkman-Grant rule seem to be valid concepts also for advanced reactors. However, a significant influence of cyclic softening on creep rates and stress rupture data can be expected as shown for grade 91. This is particularly true for creep-fatigue interactions. Based on cyclic stress-strain behaviour it is also possible to get very good life-time predictions under creep-fatigue with a strain range separation (inelastic fatigue and creep ranges) technique which could replace the currently used linear life fraction rule. Results from in-beam irradiation creep reveal no significant influence of dispersoid size. It can be assumed that irradiation creep is a matrix property. Finally it is shown that micro-sample testing of exposed material could be used as an advanced method for damage assessment in future nuclear power plants.

  18. Advanced Single-Aisle Transport Propulsion Design Options Revisited

    NASA Technical Reports Server (NTRS)

    Guynn, Mark D.; Berton, Jeffrey J.; Tong, Michael T.; Haller, William J.

    2013-01-01

    Future propulsion options for advanced single-aisle transports have been investigated in a number of previous studies by the authors. These studies have examined the system level characteristics of aircraft incorporating ultra-high bypass ratio (UHB) turbofans (direct drive and geared) and open rotor engines. During the course of these prior studies, a number of potential refinements and enhancements to the analysis methodology and assumptions were identified. This paper revisits a previously conducted UHB turbofan fan pressure ratio trade study using updated analysis methodology and assumptions. The changes incorporated have decreased the optimum fan pressure ratio for minimum fuel consumption and reduced the engine design trade-offs between minimizing noise and minimizing fuel consumption. Nacelle drag and engine weight are found to be key drivers in determining the optimum fan pressure ratio from a fuel efficiency perspective. The revised noise analysis results in the study aircraft being 2 to 4 EPNdB (cumulative) quieter due to a variety of reasons explained in the paper. With equal core technology assumed, the geared engine architecture is found to be as good as or better than the direct drive architecture for most parameters investigated. However, the engine ultimately selected for a future advanced single-aisle aircraft will depend on factors beyond those considered here.

  19. Optical design and characterization of an advanced computational imaging system

    NASA Astrophysics Data System (ADS)

    Shepard, R. Hamilton; Fernandez-Cull, Christy; Raskar, Ramesh; Shi, Boxin; Barsi, Christopher; Zhao, Hang

    2014-09-01

    We describe an advanced computational imaging system with an optical architecture that enables simultaneous and dynamic pupil-plane and image-plane coding accommodating several task-specific applications. We assess the optical requirement trades associated with custom and commercial-off-the-shelf (COTS) optics and converge on the development of two low-cost and robust COTS testbeds. The first is a coded-aperture programmable pixel imager employing a digital micromirror device (DMD) for image plane per-pixel oversampling and spatial super-resolution experiments. The second is a simultaneous pupil-encoded and time-encoded imager employing a DMD for pupil apodization or a deformable mirror for wavefront coding experiments. These two testbeds are built to leverage two MIT Lincoln Laboratory focal plane arrays - an orthogonal transfer CCD with non-uniform pixel sampling and on-chip dithering and a digital readout integrated circuit (DROIC) with advanced on-chip per-pixel processing capabilities. This paper discusses the derivation of optical component requirements, optical design metrics, and performance analyses for the two testbeds built.

  20. Design and analysis of advanced flight planning concepts

    NASA Technical Reports Server (NTRS)

    Sorensen, John A.

    1987-01-01

    The objectives of this continuing effort are to develop and evaluate new algorithms and advanced concepts for flight management and flight planning. This includes the minimization of fuel or direct operating costs, the integration of the airborne flight management and ground-based flight planning processes, and the enhancement of future traffic management systems design. Flight management (FMS) concepts are for on-board profile computation and steering of transport aircraft in the vertical plane between a city pair and along a given horizontal path. Flight planning (FPS) concepts are for the pre-flight ground based computation of the three-dimensional reference trajectory that connects the city pair and specifies the horizontal path, fuel load, and weather profiles for initializing the FMS. As part of these objectives, a new computer program called EFPLAN has been developed and utilized to study advanced flight planning concepts. EFPLAN represents an experimental version of an FPS. It has been developed to generate reference flight plans compatible as input to an FMS and to provide various options for flight planning research. This report describes EFPLAN and the associated research conducted in its development.

  1. Development of Balanced SIS Mixers for ALMA Band-10

    NASA Astrophysics Data System (ADS)

    Shitov, Sergey V.; Koryukin, Oleg V.; Uzawa, Yoshinory; Noguchi, Takashi; Uvarov, Andrey V.; Cohn, Ilya A.

    2006-05-01

    A few concepts of a wide-band balanced SIS mixer employing submicron-sized SIS junctions are under development for 787-950 GHz frequency range. A quasioptical DSB balanced mixer with integrated cross-slot antenna is considered as the less laborious and cheaper option. The silicon lens-antenna beam efficiency is expected above 80 % across the whole band with first-order sidelobe below -16 dB. To use the conservative horn antenna solution, a single chamber waveguide DSB balanced mixer is developed. Two equal probe-type SIS chips are inserted into a full-height waveguide through its opposite broad walls; these two mixers are driven by the signal waveguide in series. The LO current is transferred to the mixers in parallel via a capacitive probe inserted through the narrow wall of the signal waveguide from the neighboring LO waveguide. The HFSS model demonstrated the LO power coupling efficiency above -3 dB, almost perfect signal transfer and the LO cross talk below -30 dB that take into account misalignment (misbalance) of the chips. It is demonstrated numerically using Tucker's 3-port model that unequal pump of junctions of a twin-SIS mixer can lead, in spite of the perfect signal coupling, to degradation of the gain performance up to -3 dB, especially at the top of the ALMA Band-10.

  2. Concrete Mixing Methods and Concrete Mixers: State of the Art.

    PubMed

    Ferraris, C F

    2001-01-01

    As for all materials, the performance of concrete is determined by its microstructure. Its microstructure is determined by its composition, its curing conditions, and also by the mixing method and mixer conditions used to process the concrete. This paper gives an overview of the various types of mixing methods and concrete mixers commercially available used by the concrete industry. There are two main types of mixers used: batch mixers and continuous mixers. Batch mixers are the most common. To determine the mixing method best suited for a specific application, factors to be considered include: location of the construction site (distance from the batching plant), the amount of concrete needed, the construction schedule (volume of concrete needed per hour), and the cost. Ultimately, the quality of the concrete produced determines its performance after placement. An important measure of the quality is the homogeneity of the material after mixing. This paper will review mixing methods in regards to the quality of the concrete produced. Some procedures used to determine the effectiveness of the mixing will be examined. PMID:27500029

  3. Terahertz-frequency waveguide HEB mixers for spectral line astronomy

    NASA Astrophysics Data System (ADS)

    Boussaha, Faouzi; Kawamura, Jonathan; Stern, Jeffery; Jung, Cecile; Skalare, Anders; White, Victor

    2012-09-01

    We report on the development of waveguide-based mixers for operation beyond 2 THz. The mixer element is a superconducting hot-electron bolometer (HEB) fabricated on a silicon-on-insulator (SOI) substrate. Because it is beyond the capability of conventional machining techniques to produce the fine structures required for the waveguide embedding circuit for use at such high frequencies, we employ two lithography-based approaches to produce the waveguide circuit: a metallic micro-plating process akin to 3-D printing and deep reactive ion etching (DRIE) silicon micromachining. Various mixer configurations have been successfully produced using these approaches. A single-ended mixer produced by the metal plating technique has been demonstrated with a receiver noise temperature of 970 K (DSB) at a localoscillator frequency of 2.74 THz. A similar mixer, produced using a silicon-based micro-machining technique, has a noise temperature of 2000 K (DSB) at 2.56 THz. In another example, we have successfully produced a waveguide RF hybrid for operation at 2.74 THz. This is a key component in a balanced mixer, a configuration that efficiently utilizes local oscillator power, which is scarce at these frequencies. In addition to allowing us to extend the frequency of operation of waveguide-based receivers beyond 2 THz, these technologies we employ here are amenable to the production of large array receivers, where numerous copies of the same circuit, precisely the same and aligned to each other, are required.

  4. Concrete Mixing Methods and Concrete Mixers: State of the Art

    PubMed Central

    Ferraris, Chiara F.

    2001-01-01

    As for all materials, the performance of concrete is determined by its microstructure. Its microstructure is determined by its composition, its curing conditions, and also by the mixing method and mixer conditions used to process the concrete. This paper gives an overview of the various types of mixing methods and concrete mixers commercially available used by the concrete industry. There are two main types of mixers used: batch mixers and continuous mixers. Batch mixers are the most common. To determine the mixing method best suited for a specific application, factors to be considered include: location of the construction site (distance from the batching plant), the amount of concrete needed, the construction schedule (volume of concrete needed per hour), and the cost. Ultimately, the quality of the concrete produced determines its performance after placement. An important measure of the quality is the homogeneity of the material after mixing. This paper will review mixing methods in regards to the quality of the concrete produced. Some procedures used to determine the effectiveness of the mixing will be examined.

  5. Sub-Micron Long HTS Ho Electron Mixers

    NASA Technical Reports Server (NTRS)

    Harnack, 0.; Karasik, B. S.; McGrath, W. R.; Kleinsasser, A. W.; Barner, J. B.

    2000-01-01

    The hot-electron bolometer mixer made from a high-T, superconductor (HTS) was introduced recently as an alternative to a Schottky mixer at THz frequencies. The performance of the mixer depends on the total thermal conductance for heat removal from the phonon sub-system due to either length-dependent phonon diffusion or phonon escape to the substrate. We have measured both the length and temperature dependencies of the IF bandwidth of the mixers fabricated from 25-35 mn thick YBCO films on MgO and sapphire substrates. The films were grown by a laser deposition technique and electron-beam lithography was used to define bridge lengths down to 50 nm. Mixer measurements were done using signal frequencies in the range of 1-100 GHz. For 50 nm and 400 nm long devices on MgO, the 3-dB bandwidth was about 100 MHz. At temperatures below 60 K, the hot-electron plateau was clearly seen starting around 2-3 GHz. At temperatures above 70 K, the flux-flow effects begin to dominate and the IF bandwidth increases to 1-8 GHz, while the conversion efficiency drops by several dB. This temperature dependence of the IF bandwidth can account for previously reported unexpectedly high bandwidth of HTS mixers.

  6. The Advanced Photon Source (APS) Linear Accelerator: design and performance

    SciTech Connect

    White, M.M.

    1996-06-01

    The Advanced Photon Source linear accelerator (linac) system consists of a 200-MeV, 2856-MHz S-band electron linac and a 2-radiation-length- thick tungsten target followed by a 450-MeV positron linac. The linac system has operated 24 hours per day for the past two years to support accelerator commissioning and beam studies, and to provide beam for the experimental program. It achieves the design goal for positron current of 8 mA, and produces electron energies up to 650 MeV without the target in place. The linac is described, and its operation and performance are discussed. 9 refs., 3 figs., 1 tab.

  7. Advanced ICRF antenna design for R-TOKAMAK

    NASA Astrophysics Data System (ADS)

    Kako, E.; Ando, R.; Ichimura, M.; Ogawa, Y.; Amano, T.; Watari, T.

    1986-01-01

    The advanced ICRF antennas designed for the R-TOKAMAK (a proposal in the Institute of Plasma Physics, Nagoya University) are described. They are a standard loop antenna and a panel heater antenna for fast wave heating, and a waveguide antenna for ion Bernstein wave heating. The standard loop antenna is made of Al-alloy and has a simple structure to install because of radioactivation by D-T neutrons. For high power heating, a new type antenna called Panel heater antenna is proposed. It has a wide radiation area and is able to select a parallel wave number k. The field pattern of the panel heater antenna is measured. The feasibility of the waveguide antenna is discussed for ion Bernstein wave heating. The radiation from the aperture of the double ridge waveguide is experimentally estimated with a load simulating the plasma.

  8. Status and design of the Advanced Photon Source control system

    SciTech Connect

    McDowell, W.; Knott, M.; Lenkszus, F.; Kraimer, M.; Arnold, N.; Daly, R.

    1993-06-01

    This paper presents the current status of the Advanced Photon Source (APS) control system. It will discuss the design decisions which led us to use industrial standards and collaborations with other laboratories to develop the APS control system. The system uses high performance graphic workstations and the X-windows Graphical User Interface (GUI) at the operator interface level. It connects to VME/VXI-based microprocessors at the field level using TCP/IP protocols over high performance networks. This strategy assures the flexibility and expansibility of the control system. A defined interface between the system components will allow the system to evolve with the direct addition of future, improved equipment and new capabilities.

  9. Status and design of the Advanced Photon Source control system

    SciTech Connect

    McDowell, W.; Knott, M.; Lenkszus, F.; Kraimer, M.; Arnold, N.; Daly, R.

    1993-01-01

    This paper presents the current status of the Advanced Photon Source (APS) control system. It will discuss the design decisions which led us to use industrial standards and collaborations with other laboratories to develop the APS control system. The system uses high performance graphic workstations and the X-windows Graphical User Interface (GUI) at the operator interface level. It connects to VME/VXI-based microprocessors at the field level using TCP/IP protocols over high performance networks. This strategy assures the flexibility and expansibility of the control system. A defined interface between the system components will allow the system to evolve with the direct addition of future, improved equipment and new capabilities.

  10. Advances in SIS receiver technology

    NASA Technical Reports Server (NTRS)

    Frerking, M. A.

    1988-01-01

    Significant advances in SIS receiver technology since the last Asilomar meeting include: superconductor materials, integrated inductive tuning elements, and planar mounting structures. The effect of these advances is to push the upper frequency operating limit from about 600 to 1500 GHz, and to enhance the feasibility of focal plane arrays of heterodyne receivers. A fundamental high frequency operating limit of SIS mixers is set by the superconducting energy gap. A practical limitation for high frequency operation of SIS junctions is their parasitic capacitance and resistance. The performance of the mixer will be degraded by the Resistor-Capacitor rolloff. Several designs were reported for inductive elements integrated on the same substrate as the SIS junctions to tune out the bulk junction capacitance. Most millimeter SIS-based heterodyne receivers have used waveguide coupling structures. Technology has advanced to the state where programs that have a high probability of success can be defined to produce arrays of SIS receivers for frequencies as high as 1500 GHz.

  11. The Advanced Technology Solar Telescope: design and early construction

    NASA Astrophysics Data System (ADS)

    McMullin, Joseph P.; Rimmele, Thomas R.; Keil, Stephen L.; Warner, Mark; Barden, Samuel; Bulau, Scott; Craig, Simon; Goodrich, Bret; Hansen, Eric; Hegwer, Steve; Hubbard, Robert; McBride, William; Shimko, Steve; Wöger, Friedrich; Ditsler, Jennifer

    2012-09-01

    The National Solar Observatory’s (NSO) Advanced Technology Solar Telescope (ATST) is the first large U.S. solar telescope accessible to the worldwide solar physics community to be constructed in more than 30 years. The 4-meter diameter facility will operate over a broad wavelength range (0.35 to 28 μm ), employing adaptive optics systems to achieve diffraction limited imaging and resolve features approximately 20 km on the Sun; the key observational parameters (collecting area, spatial resolution, spectral coverage, polarization accuracy, low scattered light) enable resolution of the theoretically-predicted, fine-scale magnetic features and their dynamics which modulate the radiative output of the sun and drive the release of magnetic energy from the Sun’s atmosphere in the form of flares and coronal mass ejections. In 2010, the ATST received a significant fraction of its funding for construction. In the subsequent two years, the project has hired staff and opened an office on Maui. A number of large industrial contracts have been placed throughout the world to complete the detailed designs and begin constructing the major telescope subsystems. These contracts have included the site development, AandE designs, mirrors, polishing, optic support assemblies, telescope mount and coudé rotator structures, enclosure, thermal and mechanical systems, and high-level software and controls. In addition, design development work on the instrument suite has undergone significant progress; this has included the completion of preliminary design reviews (PDR) for all five facility instruments. Permitting required for physically starting construction on the mountaintop of Haleakalā, Maui has also progressed. This paper will review the ATST goals and specifications, describe each of the major subsystems under construction, and review the contracts and lessons learned during the contracting and early construction phases. Schedules for site construction, key factory testing of

  12. Factors Affecting Fiber Design and Selection for Advanced Ceramic Composites

    NASA Technical Reports Server (NTRS)

    DiCarlo, James A.

    1998-01-01

    Structural Ceramic Matrix Composites (CMC) have the potential for application in the hot sections of a variety of advanced propulsion and power systems. It is therefore necessary to have a general understanding of the key properties of CMC and Reinforcing Fibers. This need is complicated by the wide variety of application conditions and structural requirements for which CMC's will be used, and the proprietary concerns of the design engineers. CMC's, to be successful, must display properties which are competitive with the currently used high temperature structural materials: (i.e., Iron and Nickel based superalloys, tough monolithic ceramics, and carbon/carbon composites.) Structural CMC offers several areas of competition: (1) performance, (i.e., strength and strength retention, creep resistance, and thermal conductivity), (2) reliability (i.e., environmental durability, and damage tolerance) and (3) processing (i.e., capability for varying sizes and shapes, and cost effective fabrication). The presentation further discusses, and illustrates with fiber and CMC data the key fiber properties and processes which strongly affect each CMC area of competition. The presentation further discusses the current knowledge of the important factors which control the key fiber properties. A design guidelines for the optimum fiber characteristics is developed, and the currently available fibers are compared against those guidelines.

  13. TMT DMs final design and advanced prototyping results at Cilas

    NASA Astrophysics Data System (ADS)

    Sinquin, Jean-Christophe; Bastard, Arnaud; Boyer, Corinne; Cornette, Sébastien; Cousty, Raphaël.; Ellerbroek, Brent; Gilbert, Xavier; Gourdet, Benoit; Grasser, Régis; Groeninck, Denis; Guillemard, Claude; Herriot, Glen; Iannacone, Albert; Jeulin, Antoine; Moreau, Aurélien; Pagès, Hubert; Wang, Lianqi

    2012-07-01

    In order to prepare for the construction phase of the two Deformable Mirrors (DMs), which will be used in the Thirty Meter Telescope (TMT) first light Adaptive Optics (AO) system, Cilas has advanced the design of these two large size piezo DMs and has manufactured and tested a scaled demonstration prototype. The work done allowed significant reduction of the risks related to the demanding specifications of the TMT DMs; the main issues were: (i) Large pupil (up to 370 mm) and high order (up to 74x74); (ii) Relatively low operational temperature (DMs working at -30°C) (iii) New piezo material. It is important to develop such a prototype to take into account these three specifications all together (dimension, low temperature and new piezo material). The new prototype is a 6x60 actuators and has the same characteristics as the future TMT DMs. In this paper, we give the conclusions of the work through the presentation of the following items: (i) Design and finite element analysis of the two DMs and prototype; (ii) Test results obtained with the prototype with validation of the finite element analysis and compliance with the TMT AO specifications; (iii) Special focus on thermal behavior, actuator reliability and shape at rest stability.

  14. Advanced Neutron Source: Plant Design Requirements. Revision 4

    SciTech Connect

    Not Available

    1990-07-01

    The Advanced Neutron Source will be a new world-class facility for research using hot, thermal, cold, and ultra-cold neutrons. The heart of the facility will be a 330-MW (fission), heavy-water cooled and heavy-water moderated reactor. The reactor will be housed in a central reactor building, with supporting equipment located in an adjoining reactor support building. An array of cold neutron guides will fan out into a large guide hall, housing about 30 neutron research stations. Appropriate office, laboratory, and shop facilities will be included to provide a complete facility for users. The ANS is scheduled to begin operation at the Oak Ridge National Laboratory early in the next decade. This PDR document defines the plant-level requirements for the design, construction, and operation of ANS. It also defines and provides input to the individual System Design Description (SDD) documents. Together, this PDR document and the set of SDD documents will define and control the baseline configuration of ANS.

  15. Passive Safety Features in Advanced Nuclear Power Plant Design

    NASA Astrophysics Data System (ADS)

    Tahir, M.; Chughtai, I. R.; Aslam, M.

    2013-03-01

    For implementation of advance passive safety features in future nuclear power plant design, a passive safety system has been proposed and its response has been observed for Loss of Coolant Accident (LOCA) in the cold leg of a reactor coolant system. In a transient simulation the performance of proposed system is validated against existing safety injection system for a reference power plant of 325 MWe. The existing safety injection system is a huge system and consists of many active components including pumps, valves, piping and Instrumentation and Control (I&C). A good running of the active components of this system is necessary for its functionality as high head safety injection system under design basis accidents. Using reactor simulation technique, the proposed passive safety injection system and existing safety injection system are simulated and tested for their performance under large break LOCA for the same boundary conditions. Critical thermal hydraulic parameters of both the systems are presented graphically and discussed. The results obtained are approximately the same in both the cases. However, the proposed passive safety injection system is a better choice for such type of reactors due to reduction in components with improved safety.

  16. Advanced modeling and simulation to design and manufacture high performance and reliable advanced microelectronics and microsystems.

    SciTech Connect

    Nettleship, Ian (University of Pittsburgh, Pittsburgh, PA); Hinklin, Thomas; Holcomb, David Joseph; Tandon, Rajan; Arguello, Jose Guadalupe, Jr.; Dempsey, James Franklin; Ewsuk, Kevin Gregory; Neilsen, Michael K.; Lanagan, Michael (Pennsylvania State University, University Park, PA)

    2007-07-01

    An interdisciplinary team of scientists and engineers having broad expertise in materials processing and properties, materials characterization, and computational mechanics was assembled to develop science-based modeling/simulation technology to design and reproducibly manufacture high performance and reliable, complex microelectronics and microsystems. The team's efforts focused on defining and developing a science-based infrastructure to enable predictive compaction, sintering, stress, and thermomechanical modeling in ''real systems'', including: (1) developing techniques to and determining materials properties and constitutive behavior required for modeling; (2) developing new, improved/updated models and modeling capabilities, (3) ensuring that models are representative of the physical phenomena being simulated; and (4) assessing existing modeling capabilities to identify advances necessary to facilitate the practical application of Sandia's predictive modeling technology.

  17. Design and Implementation of a Laboratory-Based Drug Design and Synthesis Advanced Pharmacy Practice Experience

    PubMed Central

    Philip, Ashok; Stephens, Mark; Mitchell, Sheila L.

    2015-01-01

    Objective. To provide students with an opportunity to participate in medicinal chemistry research within the doctor of pharmacy (PharmD) curriculum. Design. We designed and implemented a 3-course sequence in drug design or drug synthesis for pharmacy students consisting of a 1-month advanced elective followed by two 1-month research advanced pharmacy practice experiences (APPEs). To maximize student involvement, this 3-course sequence was offered to third-year and fourth-year students twice per calendar year. Assessment. Students were evaluated based on their commitment to the project’s success, productivity, and professionalism. Students also evaluated the course sequence using a 14-item course evaluation rubric. Student feedback was overwhelmingly positive. Students found the experience to be a valuable component of their pharmacy curriculum. Conclusion. We successfully designed and implemented a 3-course research sequence that allows PharmD students in the traditional 4-year program to participate in drug design and synthesis research. Students report the sequence enhanced their critical-thinking and problem-solving skills and helped them develop as independent learners. Based on the success achieved with this sequence, efforts are underway to develop research APPEs in other areas of the pharmaceutical sciences. PMID:25995518

  18. Antenna Design Considerations for the Advanced Extravehicular Mobility Unit

    NASA Technical Reports Server (NTRS)

    Bakula, Casey J.; Theofylaktos, Onoufrios

    2015-01-01

    NASA is designing an Advanced Extravehicular Mobility Unit (AEMU)to support future manned missions beyond low-Earth orbit (LEO). A key component of the AEMU is the communications assembly that allows for the wireless transfer of voice, video, and suit telemetry. The Extravehicular Mobility Unit (EMU) currently used on the International Space Station (ISS) contains a radio system with a single omni-directional resonant cavity antenna operating slightly above 400 MHz capable of transmitting and receiving data at a rate of about 125 kbps. Recent wireless communications architectures are calling for the inclusion of commercial wireless standards such as 802.11 that operate in higher frequency bands at much higher data rates. The current AEMU radio design supports a 400 MHz band for low-rate mission-critical data and a high-rate band based on commercial wireless local area network (WLAN) technology to support video, communication with non-extravehicular activity (EVA) assets such as wireless sensors and robotic assistants, and a redundant path for mission-critical EVA data. This paper recommends the replacement of the existing EMU antenna with a new antenna that maintains the performance characteristics of the current antenna but with lower weight and volume footprints. NASA has funded several firms to develop such an antenna over the past few years, and the most promising designs are variations on the basic patch antenna. This antenna technology at UHF is considered by the authors to be mature and ready for infusion into NASA AEMU technology development programs.

  19. Designing and Implementing a New Advanced Level Biology Course

    ERIC Educational Resources Information Center

    Hall, Angela; Reiss, Michael J.; Rowell, Cathy; Scott, Anne

    2003-01-01

    Salters-Nuffield Advanced Biology is a new advanced level biology course, piloted from September 2002 in England with around 1200 students. This paper discusses the reasons for developing a new advanced biology course at this time, the philosophy of the project and how the materials are being written and the specification devised. The aim of the…

  20. Russian Pulsating Mixer Pump. Innovative Technology Summary Report

    SciTech Connect

    2002-03-01

    This sludge mixing/mobilization system was developed in Russia. A prototype system was evaluated by the Tanks Focus Area (TFA) and Industry and University Programs (INDP). The Russian Pulsating Mixer Pump showed promise for mixing highly viscous sludges. This project is to refine the system design (especially the control subsystem) and manufacture the system in Russia in accordance with quality standards required for deployment in radioactive waste storage tanks. Specifications and requirements are being developed by the TFA and INDP. The requirements may call for two or three of the sludge mixing systems to be delivered to Oak Ridge. DOE-Oak Ridge and the Oak Ridge National Laboratory will deploy the pulsating mixing pump system in their Gunite Tanks. These tanks are being emptied and cleaned prior to closure. Oak Ridge has deployed a number of innovative technologies in these efforts. If successful at Oak Ridge, the pulsating mixing pump system has potential application at several other DOE sites, including Savannah River, Hanford, and Idaho.

  1. Performance and application of the Quantiflex air/oxygen mixer.

    PubMed

    Richardson, F J; Nunn, J F

    1976-11-01

    The Quantiflex air/oxygen mixer is designed to dispense mixtures of air and oxygen with separate controls for total gas flow rate and oxygen concentration of the mixture within the range 21-100%. A monitoring flowmeter is provided for the mixture and also, as a safety measure, for the oxygen component. This serves as an indicator that oxygen is flowing and also permits independent calculation of the oxygen concentration of the mixture. Delivered oxygen concentrations were found to be within +/- 2% of the indicated value at flow rates between 4 and 12 litre/min with the input pressures of either or both gases at 208-415 kPa (30-60 lbf/in2.) gauge, and with or without an output pressure of 20 kPa. At total flow rates of 1.5-2 litre/min there was a maximum discrepancy of 4% below and 8% above the indicated concentration in some delivered concentrations. Acceptability, ease, accuracy and quickness of use by nurses were compared with current methods using separate flowmeters for air and oxygen and calculating the required flow rates by means of arithmetic, graph and special-purpose slide-rule (Blease). The Quantiflex prototype was the most acceptable, the easiest, the most accurate and the fastest of the techniques investigated. PMID:136976

  2. Combined Numerical/Analytical Perturbation Solutions of the Navier-Stokes Equations for Aerodynamic Ejector/Mixer Nozzle Flows

    NASA Technical Reports Server (NTRS)

    DeChant, Lawrence Justin

    1998-01-01

    In spite of rapid advances in both scalar and parallel computational tools, the large number of variables involved in both design and inverse problems make the use of sophisticated fluid flow models impractical, With this restriction, it is concluded that an important family of methods for mathematical/computational development are reduced or approximate fluid flow models. In this study a combined perturbation/numerical modeling methodology is developed which provides a rigorously derived family of solutions. The mathematical model is computationally more efficient than classical boundary layer but provides important two-dimensional information not available using quasi-1-d approaches. An additional strength of the current methodology is its ability to locally predict static pressure fields in a manner analogous to more sophisticated parabolized Navier Stokes (PNS) formulations. To resolve singular behavior, the model utilizes classical analytical solution techniques. Hence, analytical methods have been combined with efficient numerical methods to yield an efficient hybrid fluid flow model. In particular, the main objective of this research has been to develop a system of analytical and numerical ejector/mixer nozzle models, which require minimal empirical input. A computer code, DREA Differential Reduced Ejector/mixer Analysis has been developed with the ability to run sufficiently fast so that it may be used either as a subroutine or called by an design optimization routine. Models are of direct use to the High Speed Civil Transport Program (a joint government/industry project seeking to develop an economically.viable U.S. commercial supersonic transport vehicle) and are currently being adopted by both NASA and industry. Experimental validation of these models is provided by comparison to results obtained from open literature and Limited Exclusive Right Distribution (LERD) sources, as well as dedicated experiments performed at Texas A&M. These experiments have

  3. Design, Fabrication and Certification of Advanced Modular PV Power Systems

    NASA Astrophysics Data System (ADS)

    Minyard, Glen E.; Lambarski, Timothy J.

    1997-02-01

    The Design, Fabrication and Certification of Advanced Modular PV Power Systems contract is a Photovoltaic Manufacturing Technology (PVMaT) cost-shared contract under Phase 4A1 for Product Driven Systems and Component Technologies. Phase 4A1 has the goals to improve the cost-effectiveness and manufacturing efficiency of PV end-products, optimize manufacturing and packaging methods, and generally improve balance-of-system performance, integration and manufacturing. This contract has the specific goal to reduce the installed PV system life cycle costs to the customer with the ultimate goal of increasing PV system marketability and customer acceptance. The specific objectives of the project are to develop certified, standardized, modular, pre-engineered products lines of our main stand-alone systems, the Modular Autonomous PV Power Supply (MAPPS) and PV-Generator Hybrid System (Photogenset). To date, we have designed a 200 W MAPPS and a 1 kW Photogenset and are in the process of having the MAPPS certified by Underwriters Laboratories (UL Listed) and approved for hazardous locations by Factory Mutual (FM). We have also developed a manufacturing plan for product line expansion for the MAPPS. The Photogenset will be fabricated in February 1997 and will also be UL Listed. Functionality testing will be performed at NREL and Sandia with the intentions of providing verification of performance and reliability and of developing test-based performance specifications. In addition to an expansion on the goals, objectives and status of the project, specific accomplishments and benefits are also presented in this paper.

  4. Advancements in design of an autonomous satellite docking system

    NASA Astrophysics Data System (ADS)

    Hays, Anthony B.; Tchoryk, Peter, Jr.; Pavlich, Jane C.; Ritter, Greg A.; Wassick, Gregory J.

    2004-08-01

    The past five years has witnessed a significant increase in the attention given to on-orbit satellite docking and servicing. Recent world events have proven how we have come to rely on our space assets, especially during times of crisis. It has become abundantly clear that the ability to autonomously rendezvous, dock, inspect and service both military and civilian assets is no longer a nicety, but a necessity. Reconnaissance and communications satellites, even the space shuttle and International Space Station, could benefit from this capability. Michigan Aerospace Corporation, with funding from the Defense Advanced Research Projects Agency (DARPA) and the Air Force Research Laboratory (AFRL), has been refining a compact, light, compliant soft-docking system. Earlier prototypes have been tested on the Marshall Space Flight Center (MSFC) flat-floor as well as on the Johnson Space Flight Center (JSC) KC-135 micro-gravity aircraft. Over the past year, refinements have been made to the mechanism based on the lessons learned from these tests. This paper discusses the optimal design that has resulted.

  5. Advanced coal gasifier-fuel cell power plant systems design

    NASA Technical Reports Server (NTRS)

    Heller, M. E.

    1983-01-01

    Two advanced, high efficiency coal-fired power plants were designed, one utilizing a phosphoric acid fuel cell and one utilizing a molten carbonate fuel cell. Both incorporate a TRW Catalytic Hydrogen Process gasifier and regenerator. Both plants operate without an oxygen plant and without requiring water feed; they, instead, require makeup dolomite. Neither plant requires a shift converter; neither plant has heat exchangers operating above 1250 F. Both plants have attractive efficiencies and costs. While the molten carbonate version has a higher (52%) efficiency than the phosphoric acid version (48%), it also has a higher ($0.078/kWh versus $0.072/kWh) ten-year levelized cost of electricity. The phosphoric acid fuel cell power plant is probably feasible to build in the near term: questions about the TRW process need to be answered experimentally, such as weather it can operate on caking coals, and how effective the catalyzed carbon-dioxide acceptor will be at pilot scale, both in removing carbon dioxide and in removing sulfur from the gasifier.

  6. Advanced Biomatrix Designs for Regenerative Therapy of Periodontal Tissues

    PubMed Central

    Kim, J.H.; Park, C.H.; Perez, R.A.; Lee, H.Y.; Jang, J.H.; Lee, H.H.; Wall, I.B.; Shi, S.; Kim, H.W.

    2014-01-01

    Periodontitis is an inflammatory disease that causes loss of the tooth-supporting apparatus, including periodontal ligament, cementum, and alveolar bone. A broad range of treatment options is currently available to restore the structure and function of the periodontal tissues. A regenerative approach, among others, is now considered the most promising paradigm for this purpose, harnessing the unique properties of stem cells. How to make full use of the body’s innate regenerative capacity is thus a key issue. While stem cells and bioactive factors are essential components in the regenerative processes, matrices play pivotal roles in recapitulating stem cell functions and potentiating therapeutic actions of bioactive molecules. Moreover, the positions of appropriate bioactive matrices relative to the injury site may stimulate the innate regenerative stem cell populations, removing the need to deliver cells that have been manipulated outside of the body. In this topical review, we update views on advanced designs of biomatrices—including mimicking of the native extracellular matrix, providing mechanical stimulation, activating cell-driven matrices, and delivering bioactive factors in a controllable manner—which are ultimately useful for the regenerative therapy of periodontal tissues. PMID:25139364

  7. Fan Atomized Burner design advances & commercial development progress

    SciTech Connect

    Kamath, B.; Butcher, T.A.

    1996-07-01

    As a part of the Oil Heat Research and Development program, sponsored by the US Department of Energy, Brookhaven National Laboratory (BNL) has an on-going interest in advanced combustion technologies. This interest is aimed at: improving the initial efficiency of heating equipment, reducing long term fouling and efficiency degradation, reducing air pollutant emissions, and providing practical low-firing rate technologies which may lead to new, high efficiency oil-fired appliances. The Fan-Atomized Burner (FAB) technology is being developed at BNL as part of this general goal. The Fan-Atomized Burner uses a low pressure, air atomizing nozzle in place of the high pressure nozzle used in conventional burners. Because it is air-atomized the burner can operate at low firing rates without the small passages and reliability concerns of low input pressure nozzles. Because it uses a low pressure nozzle the burner can use a fan in place of the small compressor used in other air-atomized burner designs. High initial efficiency of heating equipment is achieved because the burner can operate at very low excess air levels. These low excess air levels also reduce the formation of sulfuric acid in flames. Sulfuric acid is responsible for scaling and fouling of heat exchanger surfaces.

  8. Advanced fiber optic face plate quality detector design

    NASA Astrophysics Data System (ADS)

    Liu, Yang; Su, Liping; Zhao, Jingxia

    2010-10-01

    A fiber optic face plate is defined by a plurality of fibers of transparent material that are fused and compressed together to transmit an image from one end to another end. Fiber optic face plates exhibit utility in the image intensifiers, cathoderay tubes, and other media displays. In this paper, the design of an advanced fiber optic face plate quality detector is presented. Modern optoelectronic imaging techniques are being used to form fiber optic plate transmission images that are suitable for analyzing the quality parameters of fiber optic face plate. The diffusing light from a halogen lamp is condensed by condenser lens then through a fiber optic face plate, a set of lenses are used to magnify the transmission image, a computer controls a long linear CCD to scan the transmission image, a data grabber captures the CCD's output data and the computer transforms the data into frame image for further analysis. Digital image processing techniques are adopted to analyze the transmission image to obtain the required quality parameters. The image analysis software combines the API that a company provided and programed API is used to acquire the quality parameter that a relevant criteria required. With the long linear CCD scanning and image analysis being computerized, it accomplishes the detection of quality parameters of fiber optic face plates automaticly. The detector can replace the manual detection method and can be widely used for the quality detection of fiber optic face plate. Manufacturers of fiber optic face plates can benefit from the detector for quality control.

  9. Composite Fan Blade Design for Advanced Engine Concepts

    NASA Technical Reports Server (NTRS)

    Abumeri, Galib H.; Kuguoglu, Latife H.; Chamis, Christos C.

    2004-01-01

    The aerodynamic and structural viability of composite fan blades of the revolutionary Exo-Skeletal engine are assessed for an advanced subsonic mission using the NASA EST/BEST computational simulation system. The Exo-Skeletal Engine (ESE) calls for the elimination of the shafts and disks completely from the engine center and the attachment of the rotor blades in spanwise compression to a rotating casing. The fan rotor overall adiabatic efficiency obtained from aerodynamic analysis is estimated at 91.6 percent. The flow is supersonic near the blade leading edge but quickly transitions into a subsonic flow without any turbulent boundary layer separation on the blade. The structural evaluation of the composite fan blade indicates that the blade would buckle at a rotor speed that is 3.5 times the design speed of 2000 rpm. The progressive damage analysis of the composite fan blade shows that ply damage is initiated at a speed of 4870 rpm while blade fracture takes place at 7640 rpm. This paper describes and discusses the results for the composite blade that are obtained from aerodynamic, displacement, stress, buckling, modal, and progressive damage analyses. It will be demonstrated that a computational simulation capability is readily available to evaluate new and revolutionary technology such as the ESE.

  10. MM wavecomponents - SIS (Superconductor-Insulator-Superconductor) mixers

    NASA Astrophysics Data System (ADS)

    Whiteley, Stephen R.

    1989-04-01

    Superconductor-Insulator-Superconductor (SIS) tunnel junction mixers are known to provide ultra-high sensitivity receiver applications above 30 GHz. In this two year (Phase 2) program, HYPRES, in collaboration with the National Radio Astronomy Observatory, developed novel fully integrated SIS mixer circuits, and demonstrated a unique high efficiency cooling system. The integrated SIS mixer chip contains, aside from the actual mixer elements, passive tuning components, an IF filter, a coplanar transmission line, and a waveguide coupler, necessary components heretofore realized off-chip. Fabrication of the integrated mixer required development of a nine level process and optimization of the process dependent electrical parameters of the SIS devices. The device performs efficiently in the range of 75-115 GHz. A novel dewar-based cooler, which makes use of the extremely low thermal conductivity of the fused silica chip substrate to achieve an incremental thermal load of 25 mW, was fabricated and demonstrated. Such a cryostat allows relatively long term unattended operation of SIS, or other, cryogenic devices.

  11. Advanced design methodologies and novel applications of reflectarray antennas

    NASA Astrophysics Data System (ADS)

    Nayeri, Payam

    Reflectarray antennas combine the numerous advantages of printed antenna arrays and reflector antennas and create a hybrid high-gain antenna with a low-profile, low-mass, and diversified radiation performance. Reflectarrays are now emerging as the new generation of high-gain antennas for long-distance communications. In this dissertation, some advanced concepts demonstrating novel features of reflectarray antennas are presented. • First, various approaches for radiation analysis of reflectarray antennas are described and implemented. Numerical results are then presented for a variety of systems and the advantages, limitations, and accuracy of these approaches are discussed and compared with each other. • A broadband technique by using sub-wavelength elements is proposed and prototypes are fabricated and tested. This technique enables the reflectarray to achieve a significant bandwidth improvement with no additional cost. • Infrared reflectarrays antennas are studied for possible applications in concentrating solar power systems. Material losses, an important design issue at infrared frequencies, are investigated and reflectarrays consisted of dielectric resonant elements are proposed with low-loss features at infrared. • Multi-beam reflectarray antennas are studied and it is demonstrated that by optimizing the phase of the elements, a desirable multi-beam performance can be achieved using a single-feed. Local and global phase-only optimization techniques have been implemented. Two Ka-band quad-beam prototypes with symmetric and asymmetric beams have been fabricated and tested. • Different approaches for beam-scanning with reflectarray antennas are also reviewed and it is shown that for moderately wide angle beam-scanning, utilizing a feed displacement technique is more suitable than an aperture phase tuning approach. A feed displacement beam-scanning design with novel aperture phase distribution is proposed for the reflectarray antenna, and is further

  12. Influence of Geometry and Flow Variations on NO Formation in the Quick Mixer of a Staged Combustor

    NASA Technical Reports Server (NTRS)

    Hatch, M. S.; Sowa, W. A.; Samuelsen, G. S.; Holdeman, J. D.

    1995-01-01

    Staged combustion, such as Rich-Burn/Quick-Mix/Lean-Burn (RQL), is a viable strategy to meet nitric oxide (NO) emission goals for both stationary and propulsion gas turbine engines. A critical element of the design is the quick mixer section where the potential for NO production is high. While numerical calculations of the quick mixer under reacting conditions have been conducted, the hostile environment and lack of appropriate diagnostics have, to date, precluded experimental probing of the reacting case. As an alternative to understanding the effect of geometry and flow variations on the production of NO in the quick mixer, the present paper presents (1) a series of non-reacting parametric studies, and (2) a computational method to extrapolate the results of the non-reacting experiments to reacting conditions. The results show that the rate of NO production is highest in the immediate vicinity of the injection plane. For a given momentum flux ratio between the jets and mainstream, the most effective mixing geometry is that which mixes effectively in both (1) the plane of injection, and (2) the wall regions downstream of the plan of injection. The tailoring of the mixing is key to minimize the NO formed. As a result, the best overall mixer with respect to the minimization of NO production may depend on the system specific characteristics of the particular application.

  13. Application of advanced electronics to a future spacecraft computer design

    NASA Technical Reports Server (NTRS)

    Carney, P. C.

    1980-01-01

    Advancements in hardware and software technology are summarized with specific emphasis on spacecraft computer capabilities. Available state of the art technology is reviewed and candidate architectures are defined.

  14. Integrated design and analysis of advanced airfoil shapes for gas turbine engines

    SciTech Connect

    Hill, B.A.; Rooney, P.J.

    1986-01-01

    An integral process in the mechanical design of gas turbine airfoils is the conversion of hot or running geometry into cold or as-manufactured geometry. New and advanced methods of design and analysis must be created that parallel new and technologically advanced turbine components. In particular, to achieve the high performance required of today's gas turbine engines, the industry is forced to design and manufacture increasingly complex airfoil shapes using advanced analysis and modeling techniques. This paper describes a method of integrating advanced, general purpose finite element analysis techniques in the mechanical design process.

  15. Saturation by Noise and CW Signals in SIS Mixers

    NASA Astrophysics Data System (ADS)

    Kerr, A. R.

    2002-03-01

    In ALMA Memo 321, Plambeck points out that saturation (gain compression) is likely to be a significant factor limiting the calibration accuracy of ALMA observations. In this paper, saturation by broadband noise and CW signals is analyzed for representative SIS receivers operating at different frequencies. Many SIS mixers in current use are expected to exhibit a significant degree of gain compression when connected to a room-temperature source. Previous analyses of saturation in SIS mixers have applied only to CW signals. To analyze saturation by noise, the statistics of the output voltage are derived from those of the input signal. A single constant, applicable to all SIS mixers, is determined experimentally by fitting the predicted CW gain compression curve to measured data.

  16. Match broadband mixers to within 1-deg. phase

    NASA Astrophysics Data System (ADS)

    Duncan, David; Roach, Patrick

    1987-01-01

    Phase matching (determined by the absolute phase difference between the mixer devices) and tracking are important mixer specifications in missile guidance and threat detection systems. In this paper, a phase-matching technique, based on a requirement that the devices track one another in sets, is presented. The technique measures phase errors down to the 1-deg level with a test setup that is repeatable and easy to use. A typical test setup and the steps of the measuring procedure are described, and data plots showing the phase-tracking performance of a set of three mixers are shown. A block diagram of a typical setup and a flow chart for a phase-matching and incremental-tracking program are included.

  17. Through the Past Decade: How Advanced Energy Design Guides have influenced the Design Industry

    SciTech Connect

    Liu, Bing; Athalye, Rahul A.

    2015-07-31

    Advanced Energy Design Guides (AEDGs) were originally developed intended to provide a simple approach to building professionals seeking energy efficient building designs better than ASHRAE Standard 90.1. Since its first book was released in 2004, the AEDG series provided inspiration for the design industry and were seen by designers as a starting point for buildings that wished to go beyond minimum codes and standards. In addition, U.S. Department of Energy’s successful Commercial Building Partnerships (CBP) program leveraged many of the recommendations from the AEDGs to achieve 50% energy savings over ASHRAE Standard 90.1-2004 for prototypical designs of large commercial entities in the retail, banking and lodging sectors. Low-energy technologies and strategies developed during the CBP process have been applied by commercial partners throughout their national portfolio of buildings. Later, the AEDGs served as the perfect platform for both Standard 90.1 and ASHRAE’s high performance buildings standard, Standard 189.1. What was high performance a few years ago, however, has become minimum code today. Indeed, most of the prescriptive envelope component requirements in ASHRAE Standard 90.1-2013 are values recommended in the 50% AEDGs several years ago. Similarly, AEDG strategies and recommendations have penetrated the lighting and HVAC sections of both Standard 189.1 and Standard 90.1. Finally, as we look to the future of codes and standards, the AEDGs are serving as a blueprint for how minimum code requirements could be expressed. By customizing codes to specific building types, design strategies tailored for individual buildings could be prescribed as minimum code, just like in the AEDGs. This paper describes the impact that AEDGs have had over the last decade on the design industry and how they continue to influence the future of codes and Standards. From design professionals to code officials, everyone in the building industry has been affected by the AEDGs.

  18. Advances in design and modeling of porous materials

    NASA Astrophysics Data System (ADS)

    Ayral, André; Calas-Etienne, Sylvie; Coasne, Benoit; Deratani, André; Evstratov, Alexis; Galarneau, Anne; Grande, Daniel; Hureau, Matthieu; Jobic, Hervé; Morlay, Catherine; Parmentier, Julien; Prelot, Bénédicte; Rossignol, Sylvie; Simon-Masseron, Angélique; Thibault-Starzyk, Frédéric

    2015-07-01

    This special issue of the European Physical Journal Special Topics is dedicated to selected papers from the symposium "High surface area porous and granular materials" organized in the frame of the conference "Matériaux 2014", held on November 24-28, 2014 in Montpellier, France. Porous materials and granular materials gather a wide variety of heterogeneous, isotropic or anisotropic media made of inorganic, organic or hybrid solid skeletons, with open or closed porosity, and pore sizes ranging from the centimeter scale to the sub-nanometer scale. Their technological and industrial applications cover numerous areas from building and civil engineering to microelectronics, including also metallurgy, chemistry, health, waste water and gas effluent treatment. Many emerging processes related to environmental protection and sustainable development also rely on this class of materials. Their functional properties are related to specific transfer mechanisms (matter, heat, radiation, electrical charge), to pore surface chemistry (exchange, adsorption, heterogeneous catalysis) and to retention inside confined volumes (storage, separation, exchange, controlled release). The development of innovative synthesis, shaping, characterization and modeling approaches enables the design of advanced materials with enhanced functional performance. The papers collected in this special issue offer a good overview of the state-of-the-art and science of these complex media. We would like to thank all the speakers and participants for their contribution to the success of the symposium. We also express our gratitude to the organization committee of "Matériaux 2014". We finally thank the reviewers and the staff of the European Physical Journal Special Topics who made the publication of this special issue possible.

  19. AEA Fluidic Pulse Jet Mixer. Innovative Technology Summary Report

    SciTech Connect

    1999-08-01

    AEA's Fluidic Pulse Jet Mixer was developed to mix and maintain the suspension of solids and to blend process liquids. The mixer can be used to combine a tank's available supernate with the sludge into a slurry that is suitable for pumping. The system uses jet nozzles in the tank coupled to a charge vessel. Then, a jet pump creates a partial vacuum in the charge vessel allowing it to be filled with waste. Next, air pressure is applied to the charge vessel, forcing sludge back into the tank and mixing it with the liquid waste. When the liquid waste contains 10% solids, a batch is pumped out of the tank.

  20. Factors which influence the behavior of turbofan forced mixer nozzles

    NASA Technical Reports Server (NTRS)

    Anderson, B. H.; Povinelli, L. A.

    1981-01-01

    A finite difference procedure was used to compute the mixing for three experimentally tested mixer geometries. Good agreement was obtained between analysis and experiment when the mechanisms responsible for secondary flow generation were properly modeled. Vorticity generation due to flow turning and vorticity generated within the centerbody lobe passage were found to be important. Results are presented for two different temperature ratios between fan and core streams and for two different free stream turbulence levels. It was concluded that the dominant mechanisms in turbofan mixers is associated with the secondary flows arising within the lobe region and their development within the mixing section.

  1. An Algorithm to Evaluate Imbalances of Quadrature Mixers

    NASA Astrophysics Data System (ADS)

    Asami, Koji; Arai, Michiaki

    It is essential, as bandwidths of wireless communications get wider, to evaluate the imbalances among quadrature mixer ports, in terms of carrier phase offset, IQ gain imbalance, and IQ skew. Because it is time consuming to separate skew, gain imbalance and carrier phase offset evaluation during test is often performed using a composite value, without separation of the imbalance factors. This paper describes an algorithm for enabling separation among quadrature mixer gain imbalance, carrier phase offset, and skew. Since the test time is reduced by the proposed method, it can be applied during high volume production testing.

  2. Josephson effect gain and noise in SIS mixers

    NASA Technical Reports Server (NTRS)

    Wengler, Michael J.; Dubash, Noshir B.; Pance, Gordana; Miller, Ronald E.

    1992-01-01

    Superconducting tunnel diode (SIS) mixers are used for radio astronomy from 100 to 500 GHz. They are being considered for NASA spaceborne astronomy at frequencies near 1000 GHz. Measurements of gain and noise in SIS mixers at 230 and 492 GHz are reported. Relatively high gain and noise associated with Josephson currents are measured that have not been previously reported. These measurements show that Josephson currents are increasingly important as operating frequencies are raised. The techniques used to make these measurements are discussed. Measurements made with hot and cold black-bodies are shown to be inaccurate at high frequencies.

  3. AZ-101 Mixer Pump Test Qualification Test Procedures (QTP)

    SciTech Connect

    THOMAS, W.K.

    2000-01-10

    Describes the Qualification test procedure for the AZ-101 Mixer Pump Data Acquisition System (DAS). The purpose of this Qualification Test Procedure (QTP) is to confirm that the AZ-101 Mixer Pump System has been properly programmed and hardware configured correctly. This QTP will test the software setpoints for the alarms and also check the wiring configuration from the SIMcart to the HMI. An Acceptance Test Procedure (ATP), similar to this QTP will be performed to test field devices and connections from the field.

  4. Advanced turbine systems program conceptual design and product development. Quarterly report, February 1995--April 1995

    SciTech Connect

    1995-06-01

    Research continued on the design of advanced turbine systems. This report describes the design and test of critical components such as blades, materials, cooling, combustion, and optical diagnostics probes.

  5. Quantum-limited 0.78-0.95-THz Waveguide SIS Mixers for the ALMA Band 10 Receivers

    NASA Astrophysics Data System (ADS)

    Kojima, Takafumi

    2010-02-01

    bandwidth might be limited by wRC. For this reason, it might have been believed that the SIS junction's current density (Jc) is the most important factor to make the RF bandwidth wider. This implies that high Jc (>20 kA/cm2) SIS junctions with very thin barrier have to be developed. For solving these issues, we have performed the investigation in detail by both design and fabrication approach. Chapter 1 offers introduction to show the importance and position of this thesis. In chapters 2 and 3, theoretical verification and feasibility of material combination for the band 10 mixers are discussed. Chapter 4 presents investigation of SIS mixers with Nb/AlOx/Nb junctions and new microstrip configuration using epitaxial NbTiN films and normal metal. The device based on NbTiN showed a receiver noise temperature of 171 K at 0.83 THz. On the other hand, the detailed analysis of mixers on the basis of numerical simulations was consistent with the experiment results, and it revealed a possibility of further improvement in the mixer performance. Chapter 5, which is the core of this thesis, describes the demonstration of a wideband and low-noise SIS mixer satisfying for the ALMA band-10 specification. The SIS mixer adopted Nb/AlOx/Nb junctions with a moderate current density of 8 kA/cm2 and low loss NbTiN/SiO2/Al inverted microstrip lines. Optimal impedances of the twin-junction circuit are theoretically investigated so as to achieve both low noise and wideband performances simultaneously. The heterodyne measurement results of this type of device showed quantum limited mixer sensitivity and wide bandwidth. Chapter 6 presents the design and the analysis of low-noise IF systems using state-of-the-art noise amplifiers and low-loss isolators. In addition, the improvement of frequency dependence of IF noise temperature and output power by detailed system consideration including the SIS mixer will be described. Chapter 7 provides the development of a waveguide SIS mixer incorporating LO

  6. Designing and Testing Contols to Mitigate Dynamic Loads in the Controls Advanced Research Turbine: Preprint

    SciTech Connect

    Wright, A.D.; Stol, K.A.

    2008-01-01

    The National Renewable Energy Laboratory is designing, implementing, and testing advanced controls to maximize energy extraction and reduce structural dynamic loads of wind turbines. These control designs are based on a linear model of the turbine that is generated by specialized modeling software. In this paper, we show the design and simulation testing of a control algorithm to mitigate blade, tower, and drivetrain loads using advanced state-space control design methods.

  7. 11. VIEW OF HORIZONTAL MIXER (GedgeGray Co., Lockland, Ohio), LOCATED ...

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

    11. VIEW OF HORIZONTAL MIXER (Gedge-Gray Co., Lockland, Ohio), LOCATED IN THE BASEMENT, MIXED ANIMAL FEED TO ORDER. THE WATER-POWERED MIXER WAS SUPERSEDED BY TWO ELECTRIC-POWERED VERTICAL MIXERS, ADDED IN THE 1940S. Photographer: Louise Taft Cawood, July 1986 - Alexander's Grist Mill, Lock 37 on Ohio & Erie Canal, South of Cleveland, Valley View, Cuyahoga County, OH

  8. Comparing Simple and Advanced Video Tools as Supports for Complex Collaborative Design Processes

    ERIC Educational Resources Information Center

    Zahn, Carmen; Pea, Roy; Hesse, Friedrich W.; Rosen, Joe

    2010-01-01

    Working with digital video technologies, particularly advanced video tools with editing capabilities, offers new prospects for meaningful learning through design. However, it is also possible that the additional complexity of such tools does "not" advance learning. We compared in an experiment the design processes and learning outcomes of 24…

  9. Interim Service ISDN Satellite (ISIS) network model for advanced satellite designs and experiments

    NASA Technical Reports Server (NTRS)

    Pepin, Gerard R.; Hager, E. Paul

    1991-01-01

    The Interim Service Integrated Services Digital Network (ISDN) Satellite (ISIS) Network Model for Advanced Satellite Designs and Experiments describes a model suitable for discrete event simulations. A top-down model design uses the Advanced Communications Technology Satellite (ACTS) as its basis. The ISDN modeling abstractions are added to permit the determination and performance for the NASA Satellite Communications Research (SCAR) Program.

  10. Conceptual design study for an advanced cab and visual system, volume 2

    NASA Technical Reports Server (NTRS)

    Rue, R. J.; Cyrus, M. L.; Garnett, T. A.; Nachbor, J. W.; Seery, J. A.; Starr, R. L.

    1980-01-01

    The performance, design, construction and testing requirements are defined for developing an advanced cab and visual system. The rotorcraft system integration simulator is composed of the advanced cab and visual system and the rotorcraft system motion generator, and is part of an existing simulation facility. User's applications for the simulator include rotorcraft design development, product improvement, threat assessment, and accident investigation.

  11. Structural and piping issues in the design certification of advanced reactors

    SciTech Connect

    Ali, S.A.; Terao, D.; Bagchi, G.

    1996-07-01

    The purpose of this paper is to discuss the design certification of structures and piping for evolutionary and passive advanced light water reactors. Advanced reactor designs are based on a set of assumed site-related parameters that are selected to envelop a majority of potential nuclear power plant sites. Multiple time histories are used as the seismic design basis in order to cover the majority of potential sites in the US. Additionally, design are established to ensure that surface motions at a particular site will not exceed the enveloped standard design surface motions. State-of-the-art soil-structure interaction (SSI) analyses have been performed for the advanced reactors, which include structure-to-structure interaction for all seismic Category 1 structures. Advanced technology has been utilized to exclude the dynamic effects of pipe rupture from structural design by demonstrating that the probability of pipe rupture is extremely low. For piping design, the advanced reactor vendors have developed design acceptance criteria (DAC) which provides the piping design analysis methods, design procedures, and acceptance criteria. In SECY-93-087 the NRC staff recommended that the Commission approve the approach to eliminate the OBE from the design of structures and piping in advanced reactors and provided guidance which identifies the necessary changes to existing seismic design criteria. The supplemental criteria address fatigue, seismic anchor motion, and piping stress limits when the OBE is eliminated.

  12. An airline study of advanced technology requirements for advanced high speed commercial transport engines. 2: Engine preliminary design assessment

    NASA Technical Reports Server (NTRS)

    Sallee, G. P.

    1973-01-01

    The advanced technology requirements for an advanced high speed commercial transport engine are presented. The results of the phase 2 study effort cover the following areas: (1) general review of preliminary engine designs suggested for a future aircraft, (2) presentation of a long range view of airline propulsion system objectives and the research programs in noise, pollution, and design which must be undertaken to achieve the goals presented, (3) review of the impact of propulsion system unreliability and unscheduled maintenance on cost of operation, (4) discussion of the reliability and maintainability requirements and guarantees for future engines.

  13. Advanced computational research in materials processing for design and manufacturing

    SciTech Connect

    Zacharia, T.

    1995-04-01

    Advanced mathematical techniques and computer simulation play a major role in providing enhanced understanding of conventional and advanced materials processing operations. Development and application of mathematical models and computer simulation techniques can provide a quantitative understanding of materials processes and will minimize the need for expensive and time consuming trial- and error-based product development. As computer simulations and materials databases grow in complexity, high performance computing and simulation are expected to play a key role in supporting the improvements required in advanced material syntheses and processing by lessening the dependence on expensive prototyping and re-tooling. Many of these numerical models are highly compute-intensive. It is not unusual for an analysis to require several hours of computational time on current supercomputers despite the simplicity of the models being studied. For example, to accurately simulate the heat transfer in a 1-m{sup 3} block using a simple computational method requires 10`2 arithmetic operations per second of simulated time. For a computer to do the simulation in real time would require a sustained computation rate 1000 times faster than that achievable by current supercomputers. Massively parallel computer systems, which combine several thousand processors able to operate concurrently on a problem are expected to provide orders of magnitude increase in performance. This paper briefly describes advanced computational research in materials processing at ORNL. Continued development of computational techniques and algorithms utilizing the massively parallel computers will allow the simulation of conventional and advanced materials processes in sufficient generality.

  14. A multichannel dual-mixer stability analyzer: progress report

    NASA Technical Reports Server (NTRS)

    Stevens, C. A.; Kirk, A.; Stevens, G. L.

    2001-01-01

    A stability analyzer is being developed for frequency standards in JPL's Deep Space Network. Prototype hardware and software have been built. Initial tests on 100-MHz sources show an Allan deviation noise floor of about 7 X 10(sup -15) at 1 second for a dual-mixer channel.

  15. Numerical study of fluid motion in bioreactor with two mixers

    NASA Astrophysics Data System (ADS)

    Zheleva, I.; Lecheva, A.

    2015-10-01

    Numerical study of hydrodynamic laminar behavior of a viscous fluid in bioreactor with multiple mixers is provided in the present paper. The reactor is equipped with two disk impellers. The fluid motion is studied in stream function-vorticity formulation. The calculations are made by a computer program, written in MATLAB. The fluid structure is described and numerical results are graphically presented and commented.

  16. Piezoelectric rotational mixer based on a first bending vibration mode.

    PubMed

    Mashimo, Tomoaki

    2013-10-01

    We propose a miniature piezoelectric mixer that can rotate a liquid inside a hole of several millimeters diameter. The mixer has dimensions 14 × 14 × 10 mm with a through-hole (7 mm), and piezoelectric elements bonded to its four identical sides. When the first bending vibration mode of the mixer is excited by ac voltages, rotational flow of liquid is generated by the rotation of an acoustic field (acoustic streaming) in the through-hole. This technology is useful in automating mixing processes such as the mixing by hand of a few drops of blood in medical testing. In this paper, we verify the driving principle experimentally and examine the characteristics of a prototype mixer, including the induced flow velocity, under changes of the amplitude and frequency of the applied voltages. A plastic test tube, used to prevent contamination, is inserted to the through-hole, and the liquid inside the tube is mixed by rotation of the acoustic field. PMID:24081258

  17. Numerical study of fluid motion in bioreactor with two mixers

    SciTech Connect

    Zheleva, I.; Lecheva, A.

    2015-10-28

    Numerical study of hydrodynamic laminar behavior of a viscous fluid in bioreactor with multiple mixers is provided in the present paper. The reactor is equipped with two disk impellers. The fluid motion is studied in stream function-vorticity formulation. The calculations are made by a computer program, written in MATLAB. The fluid structure is described and numerical results are graphically presented and commented.

  18. GUI for Computational Simulation of a Propellant Mixer

    NASA Technical Reports Server (NTRS)

    Figueroa, Fernando; Richter, Hanz; Barbieri, Enrique; Granger, Jamie

    2005-01-01

    Control Panel is a computer program that generates a graphical user interface (GUI) for computational simulation of a rocket-test-stand propellant mixer in which gaseous hydrogen (GH2) is injected into flowing liquid hydrogen (LH2) to obtain a combined flow having desired thermodynamic properties. The GUI is used in conjunction with software that models the mixer as a system having three inputs (the positions of the GH2 and LH2 inlet valves and an outlet valve) and three outputs (the pressure inside the mixer and the outlet flow temperature and flow rate). The user can specify valve characteristics and thermodynamic properties of the input fluids via userfriendly dialog boxes. The user can enter temporally varying input values or temporally varying desired output values. The GUI provides (1) a set-point calculator function for determining fixed valve positions that yield desired output values and (2) simulation functions that predict the response of the mixer to variations in the properties of the LH2 and GH2 and manual- or feedback-control variations in valve positions. The GUI enables scheduling of a sequence of operations that includes switching from manual to feedback control when a certain event occurs.

  19. Design considerations of advanced supercritical low drag suction airfoils

    NASA Technical Reports Server (NTRS)

    Pfenninger, W.; Reed, H. L.; Dagenhart, J. R.

    1980-01-01

    Supercritical low drag suction laminar flow airfoils were laid out for shock-free flow at design freestream Mach = 0.76, design lift coefficient = 0.58, and t/c = 0.13. The design goals were the minimization of suction laminarization problems and the assurance of shock-free flow at freestream Mach not greater than design freestream Mach (for design lift coefficient) as well as at lift coefficient not greater than design lift coefficient (for design freestream Mach); this involved limiting the height-to-length ratio of the supersonic zone at design to 0.35. High design freestream Mach numbers result with extensive supersonic flow (over 80% of the chord) on the upper surface, with a steep Stratford-type rear pressure rise with suction, as well as by carrying lift essentially in front- and rear-loaded regions of the airfoil with high static pressures on the carved out front and rear lower surface.

  20. Applying Hanford Tank Mixing Data to Define Pulse Jet Mixer Operation

    SciTech Connect

    Wells, Beric E.; Bamberger, Judith A.; Recknagle, Kurtis P.; Enderlin, Carl W.; Minette, Michael J.; Holton, Langdon K.

    2015-12-07

    Pulse jet mixed (PJM) process vessels are being developed for storing, blending, and chemical processing of nuclear waste slurries at the Waste Treatment and Immobilization Plant (WTP) to be built at Hanford, Washington. These waste slurries exhibit variable process feed characteristics including Newtonian to non-Newtonian rheologies over a range of solids loadings. Waste feed to the WTP from the Hanford Tank Farms will be accomplished via the Waste Feed Delivery (WFD) system which includes million-gallon underground storage double-shell tanks (DSTs) with dual-opposed jet mixer pumps. Experience using WFD type jet mixer pumps to mobilize actual Hanford waste in DSTs may be used to establish design threshold criteria of interest to pulse jet mixed process vessel operation. This paper describes a method to evaluate the pulse jet mixed vessel capability to process waste based on information obtained during mobilizing and suspending waste by the WFD system jet mixer pumps in a DST. Calculations of jet velocity and wall shear stress in a specific pulse jet mixed process vessel were performed using a commercial computational fluid dynamics (CFD) code. The CFD-modelled process vessel consists of a 4.9-m- (16-ft-) diameter tank with a 2:1 semi-elliptical head, a single, 10-cm (4-in.) downward facing 60-degree conical nozzle, and a 0.61-m (24-in.) inside diameter PJM. The PJM is located at 70% of the vessel radius with the nozzle stand-off-distance 14 cm (6 in.) above the vessel head. The CFD modeled fluid velocity and wall shear stress can be used to estimate vessel waste-processing performance by comparison to available actual WFD system process data. Test data from the operation of jet mixer pumps in the 23-m (75-ft) diameter DSTs have demonstrated mobilization, solid particles in a sediment matrix were moved from their initial location, and suspension, mobilized solid particles were moved to a higher elevation in the vessel than their initial location, of waste solids

  1. Advanced design concepts in nuclear electric propulsion. [and spacecraft configurations

    NASA Technical Reports Server (NTRS)

    Peelgren, M. L.; Mondt, J. F.

    1974-01-01

    Conceptual designs of the nuclear propulsion programs are reported. Major areas of investigation were (1) design efforts on spacecraft configuration and heat rejection subsystem, (2) high-voltage thermionic reactor concepts, and (3) dual-mode spacecraft configuration study.

  2. Advanced conceptual design report. Phase II. Liquid effluent treatment and disposal Project W-252

    SciTech Connect

    1995-01-31

    This Advanced Conceptual Design Report (ACDR) provides a documented review and analysis of the Conceptual Design Report (CDR), WHC-SD-W252-CDR-001, June 30, 1993. The ACDR provides further design evaluation of the major design approaches and uncertainties identified in the original CDR. The ACDR will provide a firmer basis for the both the design approach and the associated planning for the performance of the Definitive Design phase of the project.

  3. An analytical study for the design of advanced rotor airfoils

    NASA Technical Reports Server (NTRS)

    Kemp, L. D.

    1973-01-01

    A theoretical study has been conducted to design and evaluate two airfoils for helicopter rotors. The best basic shape, designed with a transonic hodograph design method, was modified to meet subsonic criteria. One airfoil had an additional constraint for low pitching-moment at the transonic design point. Airfoil characteristics were predicted. Results of a comparative analysis of helicopter performance indicate that the new airfoils will produce reduced rotor power requirements compared to the NACA 0012. The hodograph design method, written in CDC Algol, is listed and described.

  4. Engineering design and analysis of advanced physical fine coal cleaning technologies

    SciTech Connect

    Not Available

    1992-01-20

    This project is sponsored by the United States Department of Energy (DOE) for the Engineering Design and Analysis of Advanced Physical Fine Coal Cleaning Technologies. The major goal is to provide the simulation tools for modeling both conventional and advanced coal cleaning technologies. This DOE project is part of a major research initiative by the Pittsburgh Energy Technology Center (PETC) aimed at advancing three advanced coal cleaning technologies-heavy-liquid cylconing, selective agglomeration, and advanced froth flotation through the proof-of-concept (POC) level.

  5. Design Impacts of Stochastically-Varying Input Parameters on Advanced Thermoelectric Conversion Systems

    SciTech Connect

    Hendricks, Terry J.; Karri, Naveen K.

    2007-06-30

    Advanced, direct thermal energy conversion technologies are receiving increased research attention in order to recover waste thermal energy in advanced vehicles and industrial processes. Advanced thermoelectric (TE) systems necessarily require integrated system-level analyses to establish accurate optimum system designs. Past system-level design and analysis has relied on well-defined deterministic input parameters even though many critically important environmental and system design parameters in the above mentioned applications are often randomly variable, sometimes according to complex relationships, rather than discrete, well-known deterministic variables. This work describes new research and development creating techniques and capabilities for probabilistic design and analysis of advanced TE power generation systems to quantify the effects of randomly uncertain design inputs in determining more robust optimum TE system designs and expected outputs. Selected case studies involving stochastic TE .material properties and coupled multi-variable stochasticity in key environmental and design parameters are presented and discussed to demonstrate key impacts from considering stochastic design inputs on the TE design optimization process. Critical findings show that: 1) stochastic Gaussian input distributions may produce Gaussian or non-Gaussian outcome probability distributions for critical TE design parameters, and 2) probabilistic input considerations can create design effects that warrant significant modifications to deterministically-derived optimum TE system designs. Magnitudes and directions of these design modifications are quantified for selected TE system design analysis cases.

  6. Effects of molecular confinement and crowding on horseradish peroxidase kinetics using a nanofluidic gradient mixer.

    PubMed

    Wichert, William R A; Han, Donghoon; Bohn, Paul W

    2016-03-01

    The effects of molecular confinement and crowding on enzyme kinetics were studied at length scales and under conditions similar to those found in biological cells. These experiments were carried out using a nanofluidic network of channels constituting a nanofluidic gradient mixer, providing the basis for measuring multiple experimental conditions simultaneously. The 100 nm × 40 μm nanochannels were wet etched directly into borosilicate glass, then annealed and characterized with fluorescein emission prior to kinetic measurements. The nanofluidic gradient mixer was then used to measure the kinetics of the conversion of the horseradish peroxidase (HRP)-catalyzed conversion of non-fluorescent Amplex Red (AR) to the fluorescent product resorufin in the presence of hydrogen peroxide (H2O2). The design of the gradient mixer allows reaction kinetics to be studied under multiple (five) unique solution compositions in a single experiment. To characterize the efficiency of the device the effects of confinement on HRP-catalyzed AR conversion kinetics were studied by varying the starting ratio of AR : H2O2. Equimolar concentrations of Amplex Red and H2O2 yielded the highest reaction rates followed by 2 : 1, 1 : 2, 5 : 1, and finally 1 : 5 [AR] : [H2O2]. Under all conditions, initial reaction velocities were decreased by excess H2O2. Crowding effects on kinetics were studied by increasing solution viscosity in the nanochannels in the range 1.0-1.6 cP with sucrose. Increasing the solution viscosities in these confined geometries decreases the initial reaction velocity at the highest concentration from 3.79 μM min(-1) at 1.00 cP to 0.192 μM min(-1) at 1.59 cP. Variations in reaction velocity are interpreted in the context of models for HRP catalysis and for molecular crowding. PMID:26792298

  7. Making Wide-IF SIS Mixers with Suspended Metal-Beam Leads

    NASA Technical Reports Server (NTRS)

    Kaul, Anupama; Bumble, Bruce; Lee, Karen; LeDuc, Henry; Rice, Frank; Zmuidzinas, Jonas

    2005-01-01

    A process that employs silicon-on-insulator (SOI) substrates and silicon (Si) micromachining has been devised for fabricating wide-intermediate-frequency-band (wide-IF) superconductor/insulator/superconductor (SIS) mixer devices that result in suspended gold beam leads used for radio-frequency grounding. The mixers are formed on 25- m-thick silicon membranes. They are designed to operate in the 200 to 300 GHz frequency band, wherein wide-IF receivers for tropospheric- chemistry and astrophysical investigations are necessary. The fabrication process can be divided into three sections: 1. The front-side process, in which SIS devices with beam leads are formed on a SOI wafer; 2. The backside process, in which the SOI wafer is wax-mounted onto a carrier wafer, then thinned, then partitioned into individual devices; and 3. The release process, in which the individual devices are separated using a lithographic dicing technique. The total thickness of the starting 4-in. (10.16-cm)-diameter SOI wafer includes 25 m for the Si device layer, 0.5 m for the buried oxide (BOX) layer, and 350 m the for Si-handle layer. The front-side process begins with deposition of an etch-stop layer of SiO2 or AlN(x), followed by deposition of a Nb/Al- AlN(x) /Nb trilayer in a load-locked DC magnetron sputtering system. The lithography for four of a total of five layers is performed in a commercial wafer-stepping apparatus. Diagnostic test dies are patterned concurrently at certain locations on the wafer, alongside the mixer devices, using a different mask set. The conventional, self-aligned lift-off process is used to pattern the SIS devices up to the wire level.

  8. NASA/USRA advanced design program activity, 1991-1992

    NASA Technical Reports Server (NTRS)

    Dorrity, J. Lewis; Patel, Suneer

    1992-01-01

    The School of Textile and Fiber Engineering continued to pursue design projects with the Mechanical Engineering School giving the students an outstanding opportunity to interact with students from another discipline. Four problems were defined which had aspects which would be reasonably assigned to an interdisciplinary team. The design problems are described. The projects included lunar preform manufacturing, dust control for Enabler, an industrial sewing machine variable speed controllor, Enabler operation station, and design for producing fiberglass fabric in a lunar environment.

  9. The BWR advanced fuel design experience using Studsvik CMS

    SciTech Connect

    DiGiovine, A.S.; Gibbon, S.H.; Wiksell, G.

    1996-12-31

    The current trend within the nuclear industry is to maximize generation by extending cycle lengths and taking outages as infrequently as possible. As a result, many utilities have begun to use fuel designed to meet these more demanding requirements. These fuel designs are significantly more heterogeneous in mechanical and neutronic detail than prior designs. The question arises as to how existing in-core fuel management codes, such as Studsvik CMS perform in modeling cores containing these designs. While this issue pertains to both pressurized water reactors (PWRs) and boiling water reactors (BWRs), this summary focuses on BWR applications.

  10. Advanced software design and standards for traffic signal control

    SciTech Connect

    Bullock, D.; Hendrickson, C. )

    1992-05-01

    Improves traffic management and control systems are widely reported to be cost-effective investments. Simply retiming signals can provide significant benefits by reducing vehicle stops, travel times, and fuel consumption. The installation of advanced traffic management systems (ATMS) can provide even greater savings. However, many hardware and software obstacles have impeded the actual implementation of advanced traffic management systems. The general hardware and software limitations of current traffic signal control technology are reviewed in this paper. The impact of these deficiencies is discussed in the context of three example applications. Based on this discussion, the paper identifies several computing issues that should be addressed in order to reduce the effort involved with integrating existing traffic control devices. Adoption of standard industrial control computing platforms and development of new communication and software engineering models are recommendrecommended.

  11. Analysis and design of advanced composite bounded joints

    NASA Technical Reports Server (NTRS)

    Hart-Smith, L. J.

    1974-01-01

    Advances in the analysis of adhesive-bonded joints are presented with particular emphasis on advanced composite structures. The joints analyzed are of double-lap, single-lap, scarf, stepped-lap and tapered-lap configurations. Tensile, compressive, and in-plane shear loads are covered. In addition to the usual geometric variables, the theory accounts for the strength increases attributable to adhesive plasticity (in terms of the elastic-plastic adhesive model) and the joint strength reductions imposed by imbalances between the adherends. The solutions are largely closed-form analytical results, employing iterative solutions on a digital computer for the more complicated joint configurations. In assessing the joint efficiency, three potential failure modes are considered. These are adherend failure outside the joint, adhesive failure in shear, and adherend interlaminar tension failure (or adhesive failure in peel). Each mode is governed by a distinct mathematical analysis and each prevails throughout different ranges of geometric sizes and proportions.

  12. Advances in pulsed-power-driven radiography system design.

    SciTech Connect

    Portillo, Salvador; Hinshelwood, David D.; Rovang, Dean Curtis; Cordova, Steve Ray; Oliver, Bryan Velten; Weber, Bruce V.; Welch, Dale Robert; Shelton, Bradley Allen; Sceiford, Matthew E.; Cooperstein, Gerald; Gignac, Raymond Edward; Puetz, Elizabeth A.; Rose, David Vincent; Barker, Dennis L.; Van De Valde, David M.; Droemer, Darryl W.; Wilkins, Frank Lee; Molina, Isidro; Jaramillo, Deanna M.; Swanekamp, Stephen Brian; Commisso, Robert J.; Bailey, Vernon Leslie; Maenchen, John Eric; Johnson, David Lee; Griffin, Fawn A.; Hahn, Kelly Denise; Smith, Ian

    2004-07-01

    Flash x-ray radiography has undergone a transformation in recent years with the resurgence of interest in compact, high intensity pulsed-power-driven electron beam sources. The radiographic requirements and the choice of a consistent x-ray source determine the accelerator parameters, which can be met by demonstrated Induction Voltage Adder technologies. This paper reviews the state of the art and the recent advances which have improved performance by over an order of magnitude in beam brightness and radiographic utility.

  13. Design and fabrication of advanced EUV diffractive elements

    SciTech Connect

    Naulleau, Patrick P.; Liddle, J. Alexander; Salmassi, Farhad; Anderson, Erik H.; Gullikson, Eric M.

    2003-11-16

    As extreme ultraviolet (EUV) lithography approaches commercial reality, the development of EUV-compatible diffractive structures becomes increasingly important. Such devices are relevant to many aspects of EUV technology including interferometry, illumination, and spectral filtering. Moreover, the current scarcity of high power EUV sources makes the optical efficiency of these diffractive structures a paramount concern. This fact has led to a strong interest in phase-enhanced diffractive structures. Here we describe recent advancements made in the fabrication of such devices.

  14. NASA advanced aeronautics design solar powered remotely piloted vehicle

    NASA Technical Reports Server (NTRS)

    Elario, David S.; Guillmette, Neal H.; Lind, Gregory S.; Webster, Jonathan D.; Ferreira, Michael J.; Konstantakis, George C.; Marshall, David L.; Windt, Cari L.

    1991-01-01

    Environmental problems such as the depletion of the ozone layer and air pollution demand a change in traditional means of propulsion that is sensitive to the ecology. Solar powered propulsion is a favorable alternative that is both ecologically harmless as well as cost effective. Integration of solar energy into designs ranging from futuristic vehicles to heating is beneficial to society. The design and construction of a Multi-Purpose Remotely Piloted Vehicle (MPRPV) seeks to verify the feasibility of utilizing solar propulsion as a primary fuel source. This task has been a year long effort by a group of ten students, divided into five teams, each dealing with different aspects of the design. The aircraft was designed to take-off, climb to the design altitude, fly in a sustained figure-eight flight path, and cruise for approximately one hour. This mission requires flight at Reynolds numbers between 150,000 and 200,000 and demands special considerations in the aerodynamic design in order to achieve flight in this regime. Optimal performance requires a light weight configuration with both structural integrity and maximum power availability. The structure design and choice of solar cells for the propulsion was governed by the weight, efficiency, and cost considerations. The final design is a MPRPV weighting 35 N which cruises 7 m/s at the design altitude of 50 m. The configuration includes a wing composed of balsa and foam NACA 6409 airfoil sections and carbon fiber spars, a tail of similar construction, and a truss structure fuselage. The propulsion system consists of 98 10 percent efficient solar cells donated by Mobil Solar, a NiCad battery for energy storage, and a folding propeller regulated by a lightweight and efficient control system. The airfoils and propeller chosen for the design were research and tested during the design process.

  15. Laser direct writing 3D structures for microfluidic channels: flow meter and mixer

    NASA Astrophysics Data System (ADS)

    Lin, Chih-Lang; Liu, Yi-Jui; Lin, Zheng-Da; Wu, Bo-Long; Lee, Yi-Hsiung; Shin, Chow-Shing; Baldeck, Patrice L.

    2015-03-01

    The 3D laser direct-writing technology is aimed at the modeling of arbitrary three-dimensional (3D) complex microstructures by scanning a laser-focusing point along predetermined trajectories. Through the perspective technique, the details of designed 3D structures can be properly fabricated in a microchannel. This study introduces a direct reading flow meter and a 3D passive mixer fabricated by laser direct writing for microfluidic applications. The flow meter consists of two rod-shaped springs, a pillar, an anchor, and a wedge-shaped indicator, installed inside a microfluidic channel. The indicator is deflected by the flowing fluid while restrained by the spring to establish an equilibrium indication according to the flow rate. The measurement is readily carried out by optical microscopy observation. The 3D passive Archimedes-screw-shaped mixer is designed to disturb the laminar flow 3D direction for enhancing the mixing efficiency. The simulation results indicate that the screw provides 3D disturbance of streamlines in the microchannel. The mixing demonstration for fluids flowing in the micrchannel approximately agrees with the simulation result. Thanks to the advantage of the laser direct writing technology, this study performs the ingenious applications of 3D structures for microchannels.

  16. Simulations for membrane-based HEB mixers in array configuration for SHAHIRA

    NASA Astrophysics Data System (ADS)

    Baubert, Jean; Salez, Morvan; Merkel, Harald F.; Pons, Patrick; Delorme, Yan; Lecomte, Benoit

    2004-10-01

    We present in this paper the front-end design and the results of RF simulations, carried out with Microwave Studio (CST) and HFSS for SHAHIRA (Submillimeter Heterodyne Array for High-speed Radio Astronomy), a 4x4 heterodyne array at 2.5 THz and 4.7 THz. One can then observe 16 spatial positions at 2 frequencies. The design has been chosen to be quasi-optic, because of its simplicity, novelty and multi-pixels applicability. Pixels are made of Niobium Nitride HEB mixers with double-slot antennas, processed on 1 μm thick stress-less Si3N4/SiO2 membrane. The use of the membrane shows numerous advantages: for instance the use of the mixers at higher RF frequencies, a better power coupling efficiency or a solution for avoiding dielectric modes, losses and reflections. This work is supported by ESA and is a collaboration between LERMA, CHALMERS and LAAS. The Camera is expected to find applications, for SOFIA or CIDRE.

  17. Advanced Strategy Guideline. Air Distribution Basics and Duct Design

    SciTech Connect

    Burdick, Arlan

    2011-12-01

    This report discusses considerations for designing an air distribution system for an energy efficient house that requires less air volume to condition the space. Considering the HVAC system early in the design process will allow adequate space for equipment and ductwork and can result in cost savings.

  18. Advanced design for lightweight structures: Review and prospects

    NASA Astrophysics Data System (ADS)

    Braga, Daniel F. O.; Tavares, S. M. O.; da Silva, Lucas F. M.; Moreira, P. M. G. P.; de Castro, Paulo M. S. T.

    2014-08-01

    Current demand for fuel efficient aircraft has been pushing the aeronautical sector to develop ever more lightweight designs while keeping safe operation and required structural strength. Along with light-weighting, new structural design concepts have also been established in order to maintain the aircraft in service for longer periods of time, with high reliability levels. All these innovations and requirements have led to deeply optimized aeronautical structures contributing to more sustainable air transport. This article reviews the major design philosophies which have been employed in aircraft structures, including safe-life, fail-safe and damage tolerance taking into account their impact on the structural design. A brief historical review is performed in order to analyse what led to the development of each philosophy. Material properties are related to each of the design philosophies. Damage tolerant design has emerged as the main structural design philosophy in aeronautics, requiring deep knowledge on materials fatigue and corrosion strength, as well as potential failure modes and non-destructive inspection techniques, particularly minimum detectable defect and scan times. A discussion on the implementation of structural health monitoring and self-healing structures within the current panorama of structures designed according to the damage tolerant philosophy is presented. This discussion is aided by a review of research on these two subjects. These two concepts show potential for further improving safety and durability of aircraft structures.

  19. Advanced Simulation and Computing Co-Design Strategy

    SciTech Connect

    Ang, James A.; Hoang, Thuc T.; Kelly, Suzanne M.; McPherson, Allen; Neely, Rob

    2015-11-01

    This ASC Co-design Strategy lays out the full continuum and components of the co-design process, based on what we have experienced thus far and what we wish to do more in the future to meet the program’s mission of providing high performance computing (HPC) and simulation capabilities for NNSA to carry out its stockpile stewardship responsibility.

  20. Advanced Compressor Designs for High Energy Petawatt Pulse Generation

    SciTech Connect

    Fittinghoff, D N; Wattellier, B; Barty, C P J

    2003-09-09

    We discuss compressor designs for a proposed multikilojoule, sub-picosecond beamline at the National Ignition Facility. A novel grating configuration reduces the size of the compressor chamber. Optimization of the design leads to a 4.7 x 1.4 x 0.4 m{sup 3} minimum compressor volume.

  1. Experimental designs and their recent advances in set-up, data interpretation, and analytical applications.

    PubMed

    Dejaegher, Bieke; Heyden, Yvan Vander

    2011-09-10

    In this review, the set-up and data interpretation of experimental designs (screening, response surface, and mixture designs) are discussed. Advanced set-ups considered are the application of D-optimal and supersaturated designs as screening designs. Advanced data interpretation approaches discussed are an adaptation of the algorithm of Dong and the estimation of factor effects from supersaturated design results. Finally, some analytical applications in separation science, on the one hand, and formulation-, product-, or process optimization, on the other, are discussed. PMID:21632194

  2. Noise in Josepson effect mixers and the RSJ model

    NASA Technical Reports Server (NTRS)

    Schoelkopf, R.; Phillips, T.; Zmuidzinas, J.

    1992-01-01

    Josephson effect mixers have previously been observed to display 'excess' noise both in experiments with point contacts and in numerical simulations using the resistively shunted junction (RSJ) model. This excess noise causes the mixer noise temperature to be a factor of typically 20-100 times the physical temperature of the device. Previously, this excess was ascribed to conversion from unwanted sidebands of the local oscillator and Josephson frequencies and their harmonics. Our numerical modeling of the RSJ equations has led to a new understanding of the excess noise, which is simply due to the intrinsic Josephson oscillations of the device. In addition, we have extended the modeling to include the previously ignored case of finite device capacitance (i.e. RSJ capacitance parameter beta(sub c) does not equal 0, which is more realistic for lithographically defined Josephson such as shunted tunnel junctions or SNS bridges. For some cases, this yields an improvement of a factor of two in noise temperature from the zero capacitance models. We will discuss the device parameters which optimize the mixer performance for frequencies approaching the characteristic frequency of the device, which is given by the Josephson frequency at the I(sub c)R(sub n) voltage (nu = 2eI(sub c)R(sub n)/h). These modeling results predict good conversion efficiency and a noise temperature within a factor of a few of the physical temperature. Experiments are in progress to determine the accuracy of this modeling using a waveguide mixer at 100 GHz with optimized, resistively shunted Nb tunnel junctions. If the modeling results are valid, they are particularly encouraging for mixers in the submillimeter regime, given the possibility of obtaining non-hysteretic Josephson devices with I(sub c)R(sub n) products in excess of a millivolt, using for instance, high-T(sub c) SNS bridges. We discuss the modifications to the classical RSJ model which are necessary in the quantum regime (h nu greater

  3. Reduced T(sub c) Niobium Superconducting HEB Mixers

    NASA Technical Reports Server (NTRS)

    Siddiqi, I.; Prober, D. E.; Bumble, B.; LeDuc, H. G.

    2001-01-01

    A reduction in the mixer noise is expected when using superconductors with a lower transition temperature (T(sub c)) since the thermal noise components of the mixer noise should scale with T(sub c). Also, the local oscillator (LO) power required for a diffusion-cooled device should decrease as T(sub c) when T(sub bath) << T(sub c). We previously studied mixing in aluminum based hot-electron bolometers (HEBs) at microwave frequencies (approximately 30 GHz), and observed a significant improvement in noise performance, and a reduction in LO power as predicted. However, the bias voltage range over which good mixer performance was observed was approximately 5 - 10 microV. These devices are thus susceptible to saturation effects, in particular output saturation. In the present work, we have investigated Nb HEBs whose T(sub c) is lowered by applying a magnetic field. The goal is to study a case intermediate between Nb and Al, and hopefully to find properties that will allow use in practical receivers. A 15 kOe perpendicular magnetic field was applied to a Nb HEB (L = 0.16 micrometers, W = 0.08 micrometers, R(sub N) = 90 ohms) to reduce T(sub c) from 5.2 K to 2.4 K. The mixer noise, as inferred from the output noise and the conversion efficiency, decreased from 390 K, DSB to 171 K, DSB. The LO power required for near optimum mixer conversion efficiency (eta(sub mixer) = -9 dB in this device) was 8 nW in zero field, and approximately 2 nW when T(sub c) was reduced to 2.4 K. T(sub bath) = 0.22 K. The conversion bandwidth was previously measured to be 2.4 GHz and the same bandwidth was observed in the presence of a magnetic field. By lowering T(sub c), the voltage range over which good mixing was observed also decreased. However, even with T(sub c) reduced to 2.4 K, the conversion efficiency dropped by 3 dB from its maximum value only when the bias voltage was changed by approximately 90 microV. Saturation effects should thus be much less of a concern in these devices than in

  4. Effects of Crust Ingestion on Mixer Pump Performance in Tank 241-SY-101: Workshop Results

    SciTech Connect

    Brennen, C.E.; Stewart, C.W.; Meyer, P.A.

    1999-10-20

    In August 1999, a workshop was held at Pacific Northwest National Laboratory to discuss the effects of crust ingestion on mixer pump performance in Hanford Waste Tank 241-SY-101. The main purpose of the workshop was to evaluate the potential for crust ingestion to degrade mixing and/or damage the mixer pump. The need for a previously determined 12-inch separation between the top of the mixer pump inlet and the crust base was evaluated. Participants included a representative from the pump manufacturer, an internationally known expert in centrifugal pump theory, Hanford scientists and engineers, and operational specialists representing relevant fields of expertise. The workshop focused on developing an understanding of the pump design, addressing the physics of entrainment of solids and gases into the pump, and assessing the effects of solids and gases on pump performance. The major conclusions are summarized as follows: (1) Entrainment of a moderate amount of solids or gas from the crust should not damage the pump or reduce its lifetime, though mixing effectiveness will be somewhat reduced. (2) Air binding should not damage the pump. Vibrations due to ingestion of gas, solids, and objects potentially could cause radial loads that might reduce the lifetime of bearings and seals. However, significant damage would require extreme conditions not associated with the small bubbles, fine solids, and chunks of relatively weak material typical of the crust. (3) The inlet duct extension opening, 235 inches from the tank bottom, should be considered the pump inlet, not the small gap at 262 inches. (4) A suction vortex exists at the inlet of all pumps. The characteristics of the inlet suction vortex in the mixer pump are very hard to predict, but its effects likely extend upward several feet. Because of this, the current 12-inch limit should be replaced with criteria based on actual monitored pump performance. The most obvious criterion (in addition to current operational

  5. Specification, Design, and Analysis of Advanced HUMS Architectures

    NASA Technical Reports Server (NTRS)

    Mukkamala, Ravi

    2004-01-01

    During the two-year project period, we have worked on several aspects of domain-specific architectures for HUMS. In particular, we looked at using scenario-based approach for the design and designed a language for describing such architectures. The language is now being used in all aspects of our HUMS design. In particular, we have made contributions in the following areas. 1) We have employed scenarios in the development of HUMS in three main areas. They are: (a) To improve reusability by using scenarios as a library indexing tool and as a domain analysis tool; (b) To improve maintainability by recording design rationales from two perspectives - problem domain and solution domain; (c) To evaluate the software architecture. 2) We have defined a new architectural language called HADL or HUMS Architectural Definition Language. It is a customized version of xArch/xADL. It is based on XML and, hence, is easily portable from domain to domain, application to application, and machine to machine. Specifications written in HADL can be easily read and parsed using the currently available XML parsers. Thus, there is no need to develop a plethora of software to support HADL. 3) We have developed an automated design process that involves two main techniques: (a) Selection of solutions from a large space of designs; (b) Synthesis of designs. However, the automation process is not an absolute Artificial Intelligence (AI) approach though it uses a knowledge-based system that epitomizes a specific HUMS domain. The process uses a database of solutions as an aid to solve the problems rather than creating a new design in the literal sense. Since searching is adopted as the main technique, the challenges involved are: (a) To minimize the effort in searching the database where a very large number of possibilities exist; (b) To develop representations that could conveniently allow us to depict design knowledge evolved over many years; (c) To capture the required information that aid the

  6. Advanced Strategy Guideline: Air Distribution Basics and Duct Design

    SciTech Connect

    Burdick, A.

    2011-12-01

    This report discusses considerations for designing an air distribution system for an energy efficient house that requires less air volume to condition the space. Considering the HVAC system early in the design process will allow adequate space for equipment and ductwork and can result in cost savings. Principles discussed that will maximize occupant comfort include delivery of the proper amount of conditioned air for appropriate temperature mixing and uniformity without drafts, minimization of system noise, the impacts of pressure loss, efficient return air duct design, and supply air outlet placement, as well as duct layout, materials, and sizing.

  7. Orbit transfer vehicle advanced expander cycle engine point design study. Volume 2: Study results

    NASA Technical Reports Server (NTRS)

    Diem, H. G.

    1980-01-01

    The design characteristics of the baseline engine configuration of the advanced expander cycle engine are described. Several aspects of engine optimization are considered which directly impact the design of the baseline thrust chamber. Four major areas of the power cycle optimization are emphasized: main turbine arrangement; cycle engine source; high pressure pump design; and boost pump drive.

  8. The ergonomics of computer aided design within advanced manufacturing technology.

    PubMed

    John, P A

    1988-03-01

    Many manufacturing companies have now awakened to the significance of computer aided design (CAD), although the majority of them have only been able to purchase computerised draughting systems of which only a subset produce direct manufacturing data. Such companies are moving steadily towards the concept of computer integrated manufacture (CIM), and this demands CAD to address more than draughting. CAD architects are thus having to rethink the basic specification of such systems, although they typically suffer from an insufficient understanding of the design task and have consequently been working with inadequate specifications. It is at this fundamental level that ergonomics has much to offer, making its contribution by encouraging user-centred design. The discussion considers the relationships between CAD and: the design task; the organisation and people; creativity; and artificial intelligence. It finishes with a summary of the contribution of ergonomics. PMID:15676646

  9. Design, analysis and test verification of advanced encapsulation systems

    NASA Technical Reports Server (NTRS)

    Garcia, A.; Minning, C.

    1982-01-01

    Analytical models were developed to perform optical, thermal, electrical and structural analyses on candidate encapsulation systems. Qualification testing, specimens of various types, and a finalized optimum design are projected.

  10. ABWR (advanced boiling water reactor) Design Verification Program

    SciTech Connect

    Fox, J.N.

    1990-10-01

    The ABWR Design Verification Program is aimed at restoring confidence in the US licensing process by demonstrating its workability by obtaining USNRC preapproval of GE's ABWR Standard Plant. The purpose of this work is to achieve full NRC approval of the ABWR through the award of an NRC Staff final design approval (FDA) and design certification. The approach is to (1) establish a licensing basis with the NRC Staff for the ABWR, (2) prepare and submit, for NRC Staff review, an SSAR to obtain an FDA, and (3) participate in a rulemaking process to obtain certification of the ABWR design. This program was initiated August 27, 1986. This report, the fourth annual progress report, summarizes progress on this program from October 1, 1989 through September 30, 1990. 9 refs., 5 tabs.

  11. 50 MW, 35 GHz Gyroklystron Design for Advanced Accelerators

    NASA Astrophysics Data System (ADS)

    Arjona, Melany; Lawson, Wes

    1999-11-01

    We present the design results for a 50 MW, 35 GHz, 4-cavity gyroklystron system. We present both the design of the double-anode magnetron injection gun and the microwave circuit. The gun produces a 500 kV, 300 A beam with a velocity ratio of 1.5 and an axial spread of about 5The interaction efficiency is near 4050 dB. Details of the simulations, including sensitivity studies, will be given in the talk.

  12. Innovations in Science and Mathematics Education: Advanced Designs for Technologies of Learning.

    ERIC Educational Resources Information Center

    Jacobson, Michael J., Ed.; Kozma, Robert B., Ed.

    This collection of essays consists of current work that addresses the challenge not just to put the newest technologies in schools, but to identify advanced ways to design and use these new technologies to advance learning. These essays are intended for science and mathematics educators, educational and cognitive researchers, instructional…

  13. Advanced Information Technology in Simulation Based Life Cycle Design

    NASA Technical Reports Server (NTRS)

    Renaud, John E.

    2003-01-01

    In this research a Collaborative Optimization (CO) approach for multidisciplinary systems design is used to develop a decision based design framework for non-deterministic optimization. To date CO strategies have been developed for use in application to deterministic systems design problems. In this research the decision based design (DBD) framework proposed by Hazelrigg is modified for use in a collaborative optimization framework. The Hazelrigg framework as originally proposed provides a single level optimization strategy that combines engineering decisions with business decisions in a single level optimization. By transforming this framework for use in collaborative optimization one can decompose the business and engineering decision making processes. In the new multilevel framework of Decision Based Collaborative Optimization (DBCO) the business decisions are made at the system level. These business decisions result in a set of engineering performance targets that disciplinary engineering design teams seek to satisfy as part of subspace optimizations. The Decision Based Collaborative Optimization framework more accurately models the existing relationship between business and engineering in multidisciplinary systems design.

  14. Preconceptual design requirements for the X-1 Advanced Radiation Source

    SciTech Connect

    Rochau, G.E.; Hands, J.A.; Raglin, P.S.; Ramirez, J.J.; Goldstein, S.A.; Cereghino, S.J.; MacLeod, G.

    1998-09-01

    The X-1 Advanced Radiation Source represents the next step in providing the US Department of Energy`s Stockpile Stewardship Program with the high-energy, large volume, laboratory x-ray source for the Radiation Effects Science and Simulation, Inertial Confinement Fusion, and Weapon Physics Programs. Advances in fast pulsed power technology and in z-pinch hohlraums on Sandia National Laboratories` Z Accelerator provide sufficient basis for pursuing the development of X-1. The X-1 plan follows a strategy based on scaling the 2 MJ x-ray output on Z via a 3-fold increase in z-pinch load current. The large volume (>5 cm{sup 3}), high temperature (>150 eV), temporally long (>10 ns) hohlraums are unique outside of underground nuclear weapon testing. Analytical scaling arguments and hydrodynamic simulations indicate that these hohlraums at temperatures of 230--300 eV will ignite thermonuclear fuel and drive the reaction to a yield of 200 to 1,000 MJ in the laboratory. X-1 will provide the high-fidelity experimental capability to certify the survivability and performance of non-nuclear weapon components in hostile radiation environments. Non-ignition sources will provide cold x-ray environments (<15 keV), and high yield fusion burn sources will provide high fidelity warm x-ray environments (15 keV--80 keV).

  15. A Review of Advanced Sewer System Design Technologies (WERF Report INFR4SG09d)

    EPA Science Inventory

    Abstract: This document seeks to collect into one place current and new technologies about sewerage system design. The document organizes the information found in the 295 documents that were reviewed into six subject areas: Advanced Onsite Technologies; Alternative Wastewater C...

  16. An airline study of advanced technology requirements for advanced high speed commercial transport engines. 1: Engine design study assessment

    NASA Technical Reports Server (NTRS)

    Sallee, G. P.

    1973-01-01

    The advanced technology requirements for an advanced high speed commercial tranport engine are presented. The results of the phase 1 study effort cover the following areas: (1) statement of an airline's major objectives for future transport engines, (2) airline's method of evaluating engine proposals, (3) description of an optimum engine for a long range subsonic commercial transport including installation and critical design features, (4) discussion of engine performance problems and experience with performance degradation, (5) trends in engine and pod prices with increasing technology and objectives for the future, (6) discussion of the research objectives for composites, reversers, advanced components, engine control systems, and devices to reduce the impact of engine stall, and (7) discussion of the airline objectives for noise and pollution reduction.

  17. A Design Heritage-Based Forecasting Methodology for Risk Informed Management of Advanced Systems

    NASA Technical Reports Server (NTRS)

    Maggio, Gaspare; Fragola, Joseph R.

    1999-01-01

    The development of next generation systems often carries with it the promise of improved performance, greater reliability, and reduced operational costs. These expectations arise from the use of novel designs, new materials, advanced integration and production technologies intended for functionality replacing the previous generation. However, the novelty of these nascent technologies is accompanied by lack of operational experience and, in many cases, no actual testing as well. Therefore some of the enthusiasm surrounding most new technologies may be due to inflated aspirations from lack of knowledge rather than actual future expectations. This paper proposes a design heritage approach for improved reliability forecasting of advanced system components. The basis of the design heritage approach is to relate advanced system components to similar designs currently in operation. The demonstrated performance of these components could then be used to forecast the expected performance and reliability of comparable advanced technology components. In this approach the greater the divergence of the advanced component designs from the current systems the higher the uncertainty that accompanies the associated failure estimates. Designers of advanced systems are faced with many difficult decisions. One of the most common and more difficult types of these decisions are those related to the choice between design alternatives. In the past decision-makers have found these decisions to be extremely difficult to make because they often involve the trade-off between a known performing fielded design and a promising paper design. When it comes to expected reliability performance the paper design always looks better because it is on paper and it addresses all the know failure modes of the fielded design. On the other hand there is a long, and sometimes very difficult road, between the promise of a paper design and its fulfillment; with the possibility that sometimes the reliability

  18. Natural environment design criteria for the Advanced X-ray Astrophysics Facility (AXAF) definition and preliminary design

    NASA Technical Reports Server (NTRS)

    Greene, W. M.; Vaughan, W. W.

    1984-01-01

    This document provides the natural environment design criteria requirements for use in the Advanced X-Ray Astrophysics Facility (AXAF) definition and preliminary design studies. The atmospheric dynamic and thermodynamic environments, meteoroids, radiation, magnetic fields, and physical constants are all addressed. This information will enable all groups involved in the definition and preliminary design studies to proceed with a common and consistent set of natural environment criteria requirements.

  19. Simulation models and designs for advanced Fischer-Tropsch technology

    SciTech Connect

    Choi, G.N.; Kramer, S.J.; Tam, S.S.

    1995-12-31

    Process designs and economics were developed for three grass-roots indirect Fischer-Tropsch coal liquefaction facilities. A baseline and an alternate upgrading design were developed for a mine-mouth plant located in southern Illinois using Illinois No. 6 coal, and one for a mine-mouth plane located in Wyoming using Power River Basin coal. The alternate design used close-coupled ZSM-5 reactors to upgrade the vapor stream leaving the Fischer-Tropsch reactor. ASPEN process simulation models were developed for all three designs. These results have been reported previously. In this study, the ASPEN process simulation model was enhanced to improve the vapor/liquid equilibrium calculations for the products leaving the slurry bed Fischer-Tropsch reactors. This significantly improved the predictions for the alternate ZSM-5 upgrading design. Another model was developed for the Wyoming coal case using ZSM-5 upgrading of the Fischer-Tropsch reactor vapors. To date, this is the best indirect coal liquefaction case. Sensitivity studies showed that additional cost reductions are possible.

  20. Advanced Vibration Analysis Tool Developed for Robust Engine Rotor Designs

    NASA Technical Reports Server (NTRS)

    Min, James B.

    2005-01-01

    The primary objective of this research program is to develop vibration analysis tools, design tools, and design strategies to significantly improve the safety and robustness of turbine engine rotors. Bladed disks in turbine engines always feature small, random blade-to-blade differences, or mistuning. Mistuning can lead to a dramatic increase in blade forced-response amplitudes and stresses. Ultimately, this results in high-cycle fatigue, which is a major safety and cost concern. In this research program, the necessary steps will be taken to transform a state-of-the-art vibration analysis tool, the Turbo- Reduce forced-response prediction code, into an effective design tool by enhancing and extending the underlying modeling and analysis methods. Furthermore, novel techniques will be developed to assess the safety of a given design. In particular, a procedure will be established for using natural-frequency curve veerings to identify ranges of operating conditions (rotational speeds and engine orders) in which there is a great risk that the rotor blades will suffer high stresses. This work also will aid statistical studies of the forced response by reducing the necessary number of simulations. Finally, new strategies for improving the design of rotors will be pursued.

  1. Advanced microgrid design and analysis for forward operating bases

    NASA Astrophysics Data System (ADS)

    Reasoner, Jonathan

    This thesis takes a holistic approach in creating an improved electric power generation system for a forward operating base (FOB) in the future through the design of an isolated microgrid. After an extensive literature search, this thesis found a need for drastic improvement of the FOB power system. A thorough design process analyzed FOB demand, researched demand side management improvements, evaluated various generation sources and energy storage options, and performed a HOMERRTM discrete optimization to determine the best microgrid design. Further sensitivity analysis was performed to see how changing parameters would affect the outcome. Lastly, this research also looks at some of the challenges which are associated with incorporating a design which relies heavily on inverter-based generation sources, and gives possible solutions to help make a renewable energy powered microgrid a reality. While this thesis uses a FOB as the case study, the process and discussion can be adapted to aide in the design of an off-grid small-scale power grid which utilizes high-penetration levels of renewable energy.

  2. Optimization of integrated impeller mixer via radiotracer experiments.

    PubMed

    Othman, N; Kamarudin, S K; Takriff, M S; Rosli, M I; Engku Chik, E M F; Adnan, M A K

    2014-01-01

    Radiotracer experiments are carried out in order to determine the mean residence time (MRT) as well as percentage of dead zone, V dead (%), in an integrated mixer consisting of Rushton and pitched blade turbine (PBT). Conventionally, optimization was performed by varying one parameter and others were held constant (OFAT) which lead to enormous number of experiments. Thus, in this study, a 4-factor 3-level Taguchi L9 orthogonal array was introduced to obtain an accurate optimization of mixing efficiency with minimal number of experiments. This paper describes the optimal conditions of four process parameters, namely, impeller speed, impeller clearance, type of impeller, and sampling time, in obtaining MRT and V dead (%) using radiotracer experiments. The optimum conditions for the experiments were 100 rpm impeller speed, 50 mm impeller clearance, Type A mixer, and 900 s sampling time to reach optimization. PMID:24741344

  3. Optimization of Integrated Impeller Mixer via Radiotracer Experiments

    PubMed Central

    Othman, N.; Kamarudin, S. K.; Takriff, M. S.; Rosli, M. I.; Engku Chik, E. M. F.; Adnan, M. A. K.

    2014-01-01

    Radiotracer experiments are carried out in order to determine the mean residence time (MRT) as well as percentage of dead zone, Vdead (%), in an integrated mixer consisting of Rushton and pitched blade turbine (PBT). Conventionally, optimization was performed by varying one parameter and others were held constant (OFAT) which lead to enormous number of experiments. Thus, in this study, a 4-factor 3-level Taguchi L9 orthogonal array was introduced to obtain an accurate optimization of mixing efficiency with minimal number of experiments. This paper describes the optimal conditions of four process parameters, namely, impeller speed, impeller clearance, type of impeller, and sampling time, in obtaining MRT and Vdead (%) using radiotracer experiments. The optimum conditions for the experiments were 100 rpm impeller speed, 50 mm impeller clearance, Type A mixer, and 900 s sampling time to reach optimization. PMID:24741344

  4. Ionic electroactive polymer actuators as active microfluidic mixers

    SciTech Connect

    Meis, Catherine; Montazami, Reza; Hashemi, Nastaran

    2015-11-06

    On-chip sample processing is integral to the continued development of lab-on-a-chip devices for various applications. An active microfluidic mixer prototype is proposed using ionic electroactive polymer actuators (IEAPAs) as artificial cilia. A proof-of-concept experiment was performed in which the actuators were shown to produce localized flow pattern disruptions in the laminar flow regime. Suggestions for further engineering and optimization of a scaled-down, complete device are provided. Furthermore, the device in its current state of development necessitates further engineering, the use of IEAPAs addresses issues currently associated with the use of electromechanical actuators as active microfluidic mixers and may prove to be a useful alternative to other similar materials.

  5. Ionic electroactive polymer actuators as active microfluidic mixers

    DOE PAGESBeta

    Meis, Catherine; Montazami, Reza; Hashemi, Nastaran

    2015-11-06

    On-chip sample processing is integral to the continued development of lab-on-a-chip devices for various applications. An active microfluidic mixer prototype is proposed using ionic electroactive polymer actuators (IEAPAs) as artificial cilia. A proof-of-concept experiment was performed in which the actuators were shown to produce localized flow pattern disruptions in the laminar flow regime. Suggestions for further engineering and optimization of a scaled-down, complete device are provided. Furthermore, the device in its current state of development necessitates further engineering, the use of IEAPAs addresses issues currently associated with the use of electromechanical actuators as active microfluidic mixers and may prove tomore » be a useful alternative to other similar materials.« less

  6. Full Service ISDN Satellite (FSIS) network model for advanced ISDN satellite design and experiments

    NASA Technical Reports Server (NTRS)

    Pepin, Gerard R.

    1992-01-01

    The Full Service Integrated Services Digital Network (FSIS) network model for advanced satellite designs describes a model suitable for discrete event simulations. A top down model design uses the Advanced Communications Technology Satellite (ACTS) as its basis. The ACTS and the Interim Service ISDN Satellite (ISIS) perform ISDN protocol analyses and switching decisions in the terrestrial domain, whereas FSIS makes all its analyses and decisions on-board the ISDN satellite.

  7. Newman Unit 1 advanced solar repowering advanced conceptual design. Final report

    SciTech Connect

    1982-04-01

    The Newman Unit 1 solar repowering design is a water/steam central receiver concept supplying superheated steam. The work reported is to develop a refined baseline conceptual design that has potential for construction and operation by 1986, makes use of existing solar thermal technology, and provides the best economics for this application. Trade studies performed in the design effort are described, both for the conceptual design of the overall system and for the subsystem conceptual design. System-level functional requirements, design, operation, performance, cost, safety, environmental, institutional, and regulatory considerations are described. Subsystems described include the collector, receiver, fossil energy, electrical power generating, and master control subsystems, site and site facilities. The conceptual design, cost, and performance of each subsystem is discussed at length. A detailed economic analysis of the repowered unit is made to realistically assess the economics of the first repowered unit using present cost data for a limited production level for solar hardware. Finally, a development plan is given, including the design, procurement, construction, checkout, startup, performance validation, and commercial operation. (LEW)

  8. Advanced Design Heat PumpRadiator for EVA Suits

    NASA Technical Reports Server (NTRS)

    Izenson, Michael G.; Chen, Weibo; Passow, Christian; Phillips, Scott; Trevino, Luis

    2009-01-01

    Absorption cooling using a LiCl/water heat pump can enable lightweight and effective thermal control for EVA suits without venting water to the environment. The key components in the system are an absorber/radiator that rejects heat to space and a flexible evaporation cooling garment that absorbs heat from the crew member. This paper describes progress in the design, development, and testing of the absorber/radiator and evaporation cooling garment. New design concepts and fabrication approaches will significantly reduce the mass of the absorber/radiator. We have also identified materials and demonstrated fabrication approaches for production of a flexible evaporation cooling garment. Data from tests of the absorber/radiator s modular components have validated the design models and allowed predictions of the size and weight of a complete system.

  9. Advanced two-stage compressor program design of inlet stage

    NASA Technical Reports Server (NTRS)

    Bryce, C. A.; Paine, C. J.; Mccutcheon, A. R. S.; Tu, R. K.; Perrone, G. L.

    1973-01-01

    The aerodynamic design of an inlet stage for a two-stage, 10/1 pressure ratio, 2 lb/sec flow rate compressor is discussed. Initially a performance comparison was conducted for an axial, mixed flow and centrifugal second stage. A modified mixed flow configuration with tandem rotors and tandem stators was selected for the inlet stage. The term conical flow compressor was coined to describe a particular type of mixed flow compressor configuration which utilizes axial flow type blading and an increase in radius to increase the work input potential. Design details of the conical flow compressor are described.

  10. Design aspects of the XV-15 advanced technology blade program

    NASA Technical Reports Server (NTRS)

    Smith, K. E.; Alexander, H. R.; Maisel, M. D.

    1985-01-01

    The paper discusses the design of a tiltrotor blade for application to the XV-15 research demonstration aircraft. The design features 43 deg nonlinear twist and nonuniform tapered planform. The structure is composite with extensive use of graphite in the primary structure. Instrumentation and wiring is encapsulated in the composite structure during the cure cycle. The tip shell is removable, providing access to the tracking and balance weights. This feature provides research facility of alternate tip configurations. The cuff is similarly removable. The graphite epoxy system used is high strain American Cyanamid's Celion 6000ST/Cycom 950. This is the first application of this material in rotor blades.

  11. Design feasibility of an advanced technology supersonic cruise aircraft

    NASA Technical Reports Server (NTRS)

    Rowe, W. T.

    1976-01-01

    Research and development programs provide confidence that technology is in-hand to design an economically attractive, environmentally sound supersonic cruise aircraft for commercial operations. The principal results of studies and tests are described including those which define the selection of significant design features. These typically include the results of: (1) wind-tunnel tests, both subsonic and supersonic, (2) propulsion performance and acoustic tests on noise suppressors, including forward-flight effects, (3) studies of engine/airframe integration, which lead to the selection of engine cycles/sizes to meet future market, economic, and social requirements; and (4) structural testing.

  12. Thermal design for the Advanced Camera for Surveys

    NASA Astrophysics Data System (ADS)

    Rafal, Marc D.

    1998-08-01

    The advanced camera for surveys (ACS) is a third generation science instrument scheduled for installation into the Hubble Space Telescope (HST) during the third servicing mission scheduled for 1999. ACS, along with the previously installed space telescope imaging spectrograph and near IR camera/multi-object spectrograph, consume significantly more power than the first generation of instruments. Additionally, the larger apertures of these instruments make parallel operations scientifically exciting. These parallel operations demand that all of the instruments operate in their highest power states simultaneously for extended periods of time. These and other factors have resulted in much higher temperatures inside the aft shroud where the ACS will be installed. As a result, new approaches are required to transfer heat inside the instrument and reject it away from the telescope. This paper describes the unique thermal systems required by the ACS. These include capillary pump loops and flexible and rigid heat pipes.

  13. Red Fluorescent Proteins: Advanced Imaging Applications and Future Design

    PubMed Central

    Shcherbakova, Daria M.; Subach, Oksana M.; Verkhusha, Vladislav V.

    2015-01-01

    In the past few years a large series of the advanced red-shifted fluorescent proteins (RFPs) has been developed. These enhanced RFPs provide new possibilities to study biological processes at the levels ranging from single molecules to whole organisms. Herein the relationship between the properties of the RFPs of different phenotypes and their applications to various imaging techniques are described. Existing and emerging imaging approaches are discussed for conventional RFPs, far-red FPs, RFPs with a large Stokes shift, fluorescent timers, irreversibly photoactivatable and reversibly photo-switchable RFPs. Advantages and limitations of specific RFPs for each technique are presented. Recent progress in understanding the chemical transformations of red chromophores allows the future RFP phenotypes and their respective novel imaging applications to be foreseen. PMID:22851529

  14. 670-GHz Down- and Up-Converting HEMT-Based Mixers

    NASA Technical Reports Server (NTRS)

    Schlecht, Enrich T.; Chattopadhyay, Goutam; Lin, Robert H.; Sin, Seth; Deal, William; Rodriquez, Bryan; Bayuk, Brian; Leong, Kevin; Mei, Gerry

    2012-01-01

    A large category of scientific investigation takes advantage of the interactions of signals in the frequency range from 300 to 1,000 GHz and higher. This includes astronomy and atmospheric science, where spectral observations in this frequency range give information about molecular abundances, pressures, and temperatures of small-sized molecules such as water. Additionally, there is a minimum in the atmospheric absorption at around 670 GHz that makes this frequency useful for terrestrial imaging, radar, and possibly communications purposes. This is because 670 GHz is a good compromise for imaging and radar applications between spatial resolution (for a given antenna size) that favors higher frequencies, and atmospheric losses that favor lower frequencies. A similar trade-off applies to communications link budgets: higher frequencies allow smaller antennas, but incur a higher loss. All of these applications usually require converting the RF (radio frequency) signal at 670 GHz to a lower IF (intermediate frequency) for processing. Further, transmitting for communication and radar generally requires up-conversion from IF to the RF. The current state-of-the-art device for performing the frequency conversion is based on Schottky diode mixers for both up and down conversion in this frequency range for room-temperature operation. Devices that can operate at room temperature are generally required for terrestrial, military, and planetary applications that cannot tolerate the mass, bulk, and power consumption of cryogenic cooling. The technology has recently advanced to the point that amplifiers in the region up to nearly 1,000 GHz are feasible. Almost all of these have been based on indium phosphide pseudomorphic high-electron mobility transistors (pHEMTs), in the form of monolithic microwave integrated circuits (MMICs). Since the processing of HEMT amplifiers is quite differ en t from that of Schottky diodes, use of Schottky mixers requires separate MMICs for the mixers

  15. Dynamics and Control of Orbiting Space Structures NASA Advanced Design Program (ADP)

    NASA Technical Reports Server (NTRS)

    Cruse, T. A.

    1996-01-01

    The report summarizes the advanced design program in the mechanical engineering department at Vanderbilt University for the academic years 1994-1995 and 1995-1996. Approximately 100 students participated in the two years of the subject grant funding. The NASA-oriented design projects that were selected included lightweight hydrogen propellant tank for the reusable launch vehicle, a thermal barrier coating test facility, a piezoelectric motor for space antenna control, and a lightweight satellite for automated materials processing. The NASA supported advanced design program (ADP) has been a success and a number of graduates are working in aerospace and are doing design.

  16. 100-GHz Phase Switch/Mixer Containing a Slot-Line Transition

    NASA Technical Reports Server (NTRS)

    Gaier, Todd; Wells, Mary; Dawson, Douglas

    2009-01-01

    A circuit that can function as a phase switch, frequency mixer, or frequency multiplier operates over a broad frequency range in the vicinity of 100 GHz. Among the most notable features of this circuit is a grounded uniplanar transition (in effect, a balun) between a slot line and one of two coplanar waveguides (CPWs). The design of this circuit is well suited to integration of the circuit into a microwave monolithic integrated circuit (MMIC) package. One CPW is located at the input end and one at the output end of the top side of a substrate on which the circuit is fabricated (see Figure 1). The input CPW feeds the input signal to antiparallel flip-chip Schottky diodes connected to the edges of the slot line. Phase switching is effected by the combination of (1) the abrupt transition from the input CPW to the slot line and (2) CPW ground tuning effected by switching of the bias on the diodes. Grounding of the slot metal to the bottom metal gives rise to a frequency cutoff in the slot. This cutoff is valuable for separating different frequency components when the circuit is used as a mixer or multiplier. Proceeding along the slot line toward the output end, one encounters the aforementioned transition, which couples the slot line to the output CPW. Impedance tuning of the transition is accomplished by use of a high-impedance section immediately before the transition.

  17. Influence of pressure driven secondary flows on the behavior of turbofan forced mixers

    NASA Technical Reports Server (NTRS)

    Anderson, B.; Povinelli, L.; Gerstenmaier, W.

    1980-01-01

    A finite difference procedure was developed to analyze the three dimensional subsonic turbulent flows in turbofan forced mixer nozzles. The method is based on a decomposition of the velocity field into primary and secondary flow components which are determined by solution of the equations governing primary momentum, secondary vorticity, thermal energy, and continuity. Experimentally, a strong secondary flow pattern was identified which is associated with the radial inflow and outflow characteristics of the core and fan streams and forms a very strong vortex system aligned with the radial interface between the core and fan regions. A procedure was developed to generate a similar generic secondary flow pattern in terms of two constants representing the average radial outflow or inflow in the core and fan streams as a percentage of the local streamwise velocity. This description of the initial secondary flow gave excellent agreement with experimental data. By identifying the nature of large scale secondary flow structure and associating it with characteristic mixer nozzle behavior, it is felt that the cause and effect relationship between lobe design and nozzle performance can be understood.

  18. Progress in Conceptual Design and Analysis of Advanced Rotorcraft

    NASA Technical Reports Server (NTRS)

    Yamauchi, Gloria K.

    2012-01-01

    This presentation will give information on Multi-Disciplinary Analysis and Technology Development, including it's objectives and how they will be met. In addition, it will also present recent highlights including the Lift-Offset Civil Design and it's study conclusions, as well as, the LCTR2 Propulsion Concept's study conclusions. Recent publications and future publications will also be discussed.

  19. Learning Design Research: Advancing Pedagogies in the Digital Age

    ERIC Educational Resources Information Center

    Dobozy, Eva

    2013-01-01

    Learning design research (LDR) is establishing itself as a separate and specialised field of educational research. Worldwide, technology-mediated learning experiences in higher and further education are on the increase. LDR investigates their success in providing effective outcomes-based and personalised learning experiences. This paper reports on…

  20. Design and performance verification of advanced multistage depressed collectors

    NASA Technical Reports Server (NTRS)

    Kosmahl, H. G.; Ramins, P.

    1975-01-01

    Design and performance of a small size, 4 stage depressed collector are discussed. The collector and a spent beam refocusing section preceding it are intended for efficiency enhancement of octave bandwidth, high CW power traveling wave tubes for use in ECM.

  1. Recent advances in the design and development of soft drugs.

    PubMed

    Buchwald, P; Bodor, N

    2014-06-01

    This paper summarizes recent developments in the field of soft drug development as collected and reviewed for the 9th Retrometabolism-Based Drug Design and Targeting Conference. Soft drugs are still often confused with prodrugs because they both require metabolic transformations; however, they are conceptual opposites: whereas, prodrugs are pharmacologically inactive and are converted by a predictable mechanism to the active drug, soft drugs are active therapeutic agents as such and are designed to undergo a predictable and controllable metabolic deactivation after exerting their desired therapeutic effect. Several rationally designed soft drug examples including clinically approved ones (e.g., clevidipine, esmolol, landiolol, loteprednol etabonate, and remifentanil) as well as others that have reached clinical investigations within different therapeutic areas (e.g., budiodarone, naronapride, remimazolam, tecarfarine) are briefly summarized. Anesthesiology, which requires a high degree of pharmacologic control during the surgical procedure to maintain the anesthetic state together with a quick return to responsiveness at the end of this procedure, is a particularly well-suited area for soft drug development. Several new initiatives (e.g., MOC-etomidate, AZD3043) are focused in this area; they are also briefly reviewed. Finally, just as there are many 'accidental' prodrugs, there are 'accidental' soft drugs too: i.e., therapeutics that were not intentionally designed to be soft drugs, but turned out to be essentially soft drugs. Some examples, such as articaine or methylphenidate, are briefly reviewed. PMID:24974571

  2. Subsonic Jet Noise Reduced With Improved Internal Exhaust Gas Mixers

    NASA Technical Reports Server (NTRS)

    1996-01-01

    Aircraft noise pollution is becoming a major environmental concern for the world community. The Federal Aviation Administration (FAA) is responding to this concern by imposing more stringent noise restrictions for aircraft certification then ever before to keep the U.S. industry competitive with the rest of the world. At the NASA Lewis Research Center, attempts are underway to develop noise-reduction technology for newer engines and for retrofitting existing engines so that they are as quiet as (or quieter than) required. Lewis conducted acoustic and Laser Doppler Velocimetry (LDV) tests using Pratt & Whitney's Internal Exhaust Gas Mixers (IEGM). The IEGM's mix the core flow with the fan flow prior to their common exhaust. All tests were conducted in Lewis' Aero-Acoustic Propulsion Laboratory--a semihemispheric dome open to the ambient atmosphere. This was the first time Laser Doppler Velocimetry was used in such a facility at Lewis. Jet exhaust velocity and turbulence and the internal velocity fields were detailed. Far-field acoustics were also measured. Pratt & Whitney provided 1/7th scale model test hardware (a 12-lobe mixer, a 20-lobe mixer, and a splitter) for 1.7 bypass ratio engines, and NASA provided the research engineers, test facility, and test time. The Pratt & Whitney JT8D-200 engine power conditions were used for all tests.

  3. Qualification test of the Ross Double Planetary Mixer

    NASA Astrophysics Data System (ADS)

    Lueders, Kurt F.

    1993-07-01

    This test report describes the qualification test of the Ross Double Planetary Mixer used to mix room temperature vulcanized (RTV) silicone (Dow Corning 90-006-2) for the redesigned solid rocket motor (RSRM) nozzle joints. Testing was completed 18 June 1993 in the M-113A Nozzle Fabrication Facility at Thiokol Corporation, Space Operations, Brigham City, Utah. The Ross mixer provides better mixing and better control on temperature and humidity, resulting in better quality RTV and a longer usable pot life. The test began on 3 May 1993 and was stopped due to operator error during the tensile strength and elongation testing. Specimens were ruined without gathering any useful data. A 'no test' was declared, the problem was remedied, and the test was re-run with MSFC approval. The test was run and all pass/fail criteria were met, most with a considerable margin. The Ross Double Planetary Mixer met all certification objectives and is recommended for immediate use for mixing RTV silicone for RSRM nozzle joints.

  4. Topics in the optimization of millimeter-wave mixers

    NASA Technical Reports Server (NTRS)

    Siegel, P. H.; Kerr, A. R.; Hwang, W.

    1984-01-01

    A user oriented computer program for the analysis of single-ended Schottky diode mixers is described. The program is used to compute the performance of a 140 to 220 GHz mixer and excellent agreement with measurements at 150 and 180 GHz is obtained. A sensitivity analysis indicates the importance of various diode and mount characteristics on the mixer performance. A computer program for the analysis of varactor diode multipliers is described. The diode operates in either the reverse biased varactor mode or with substantial forward current flow where the conversion mechanism is predominantly resistive. A description and analysis of a new H-plane rectangular waveguide transformer is reported. The transformer is made quickly and easily in split-block waveguide using a standard slitting saw. It is particularly suited for use in the millimeter-wave band, replacing conventional electroformed stepped transformers. A theoretical analysis of the transformer is given and good agreement is obtained with measurements made at X-band.

  5. A general numerical analysis program for the superconducting quasiparticle mixer

    NASA Technical Reports Server (NTRS)

    Hicks, R. G.; Feldman, M. J.; Kerr, A. R.

    1986-01-01

    A user-oriented computer program SISCAP (SIS Computer Analysis Program) for analyzing SIS mixers is described. The program allows arbitrary impedance terminations to be specified at all LO harmonics and sideband frequencies. It is therefore able to treat a much more general class of SIS mixers than the widely used three-frequency analysis, for which the harmonics are assumed to be short-circuited. An additional program, GETCHI, provides the necessary input data to program SISCAP. The SISCAP program performs a nonlinear analysis to determine the SIS junction voltage waveform produced by the local oscillator. The quantum theory of mixing is used in its most general form, treating the large signal properties of the mixer in the time domain. A small signal linear analysis is then used to find the conversion loss and port impedances. The noise analysis includes thermal noise from the termination resistances and shot noise from the periodic LO current. Quantum noise is not considered. Many aspects of the program have been adequately verified and found accurate.

  6. Jet mixer pump testing in Hanford tank 241-SY-101

    SciTech Connect

    Stewart, C.W.

    1994-12-31

    A mixer pump was found effective in controlling and possibly eliminating large flammable gas releases from Hanford Tank 241-SY-101. A gas release event (GRE) is initiated when gas-bearing sludge accumulates sufficient gas to become buoyant. The buoyant sludge pulls free from the surrounding material and rises to the surface releasing the trapped gas. Mixer pump operation is intended to keep gas-generating material in suspension so that it releases gas continuously instead of periodically in large, potentially dangerous GREs. A mixer pump was installed July 3, 1993, 7 days after a typical GRE. The initial pump operation in phase-A testing was extremely gentle, beginning with a series of daily pump {open_quotes}bumps{close_quotes} intended to keep the pump nozzles clear. Because nozzle plugging did occur, bump speed and duration were increased, eventually arriving at the accepted 5-min period at 1000 rpm on July 26. There has been no nozzle plugging since. Bumping was initially performed twice daily through mid-August and once daily until the start of phase-B testing. By the end of phase B, thrice-weekly bumping became the rule.

  7. Conceptual Design Method Developed for Advanced Propulsion Nozzles

    NASA Technical Reports Server (NTRS)

    Nadell, Shari-Beth; Barnhart, Paul J.

    1998-01-01

    As part of a contract with the NASA Lewis Research Center, a simple, accurate method of predicting the performance characteristics of a nozzle design has been developed for use in conceptual design studies. The Nozzle Performance Analysis Code (NPAC) can predict the on- and off-design performance of axisymmetric or two-dimensional convergent and convergent-divergent nozzle geometries. NPAC accounts for the effects of overexpansion or underexpansion, flow divergence, wall friction, heat transfer, and small mass addition or loss across surfaces when the nozzle gross thrust and gross thrust coefficient are being computed. NPAC can be used to predict the performance of a given nozzle design or to develop a preliminary nozzle system design for subsequent analysis. The input required by NPAC consists of a simple geometry definition of the nozzle surfaces, the location of key nozzle stations (entrance, throat, exit), and the nozzle entrance flow properties. NPAC performs three analysis "passes" on the nozzle geometry. First, an isentropic control volume analysis is performed to determine the gross thrust and gross thrust coefficient of the nozzle. During the second analysis pass, the skin friction and heat transfer losses are computed. The third analysis pass couples the effects of wall shear and heat transfer with the initial internal nozzle flow solutions to produce a system of equations that is solved at steps along the nozzle geometry. Small mass additions or losses, such as those resulting from leakage or bleed flow, can be included in the model at specified geometric sections. A final correction is made to account for divergence losses that are incurred if the nozzle exit flow is not purely axial.

  8. Design and fabrication of advanced hybrid circuits for high energy physics

    SciTech Connect

    Haller, G.M.; Moss, J.; Freytag, D.R.; Nelson, D.; Yim, A.; Lo, C.C.

    1987-10-01

    Current design and fabrication techniques of hybrid devices are explained for the Drift Chamber and the Liquid Argon Calorimeter for the Stanford Linear Collider Large Detector (SLD) at SLAC. Methods of developing layouts, ranging from hand-cut templates to advanced designs utilizing CAD tools with special hybrid design software were applied. Physical and electrical design rules for good yield and performance are discussed. Fabrication and assembly of the SLD hybrids are described. 7 refs., 10 figs.

  9. Design, fabrication and test of graphite/polyimide composite joints and attachments for advanced aerospace vehicles

    NASA Technical Reports Server (NTRS)

    1981-01-01

    The development of several types of graphite/polyimide (GR/PI) bonded and bolted joints is reported. The program consists of two concurrent tasks: (1) design and test of specific built up attachments; and (2) evaluation of standard advanced bonded joint concepts. A data base for the design and analysis of advanced composite joints for use at elevated temperatures (561K (550 deg F)) to design concepts for specific joining applications, and the fundamental parameters controlling the static strength characteristics of such joints are evaluated. Data for design and build GR/PI of lightly loaded flight components for advanced space transportation systems and high speed aircraft are presented. Results for compression and interlaminar shear strengths of Celion 6000/PMR-15 laminates are given. Static discriminator test results for type 3 and type 4 bonded and bolted joints and final joint designs for TASK 1.4 scale up fabrication and testing are presented.

  10. Design and fabrication of an advanced, lightweight, high stiffness, railgun barrel concept

    SciTech Connect

    Vrable, D.L.; Rosenwasser, S.N.; Korican, J.A. )

    1991-01-01

    An advanced lightweight and high stiffness railgun barrel design and incorporates several new design features and advanced materials is being developed by SPARTA, Inc. The program is sponsored by the U.S. Army Armament Research, Development, and Engineering Center ARDEC and by the Defense Advanced Research Projects Agency (DARPA). The railgun is 7 m long and has a 90 mm round bore. It is designed to accommodate both solid and plasma armatures. Muzzle energies are expected in the range of 9 to 15 MJ. Analysis and final design has been completed and the barrel and other railgun subassemblies are in the fabrication stage at SPARTA, Inc. in San Diego, California. Initial testing will be conducted at Maxwell Laboratories Green Farm facility in September 1990 and will subsequently be shipped to the ARDEC Railgun Laboratory in October 1990 for full power operation and testing. This paper discusses the design features and fabrication approaches for this high performance, lightweight railgun barrel system.

  11. Advanced composite structures. [metal matrix composites - structural design criteria for spacecraft construction materials

    NASA Technical Reports Server (NTRS)

    1974-01-01

    A monograph is presented which establishes structural design criteria and recommends practices to ensure the design of sound composite structures, including composite-reinforced metal structures. (It does not discuss design criteria for fiber-glass composites and such advanced composite materials as beryllium wire or sapphire whiskers in a matrix material.) Although the criteria were developed for aircraft applications, they are general enough to be applicable to space vehicles and missiles as well. The monograph covers four broad areas: (1) materials, (2) design, (3) fracture control, and (4) design verification. The materials portion deals with such subjects as material system design, material design levels, and material characterization. The design portion includes panel, shell, and joint design, applied loads, internal loads, design factors, reliability, and maintainability. Fracture control includes such items as stress concentrations, service-life philosophy, and the management plan for control of fracture-related aspects of structural design using composite materials. Design verification discusses ways to prove flightworthiness.

  12. Advanced Aerodynamic Design of Passive Porosity Control Effectors

    NASA Technical Reports Server (NTRS)

    Hunter, Craig A.; Viken, Sally A.; Wood, Richard M.; Bauer, Steven X. S.

    2001-01-01

    This paper describes aerodynamic design work aimed at developing a passive porosity control effector system for a generic tailless fighter aircraft. As part of this work, a computational design tool was developed and used to layout passive porosity effector systems for longitudinal and lateral-directional control at a low-speed, high angle of attack condition. Aerodynamic analysis was conducted using the NASA Langley computational fluid dynamics code USM3D, in conjunction with a newly formulated surface boundary condition for passive porosity. Results indicate that passive porosity effectors can provide maneuver control increments that equal and exceed those of conventional aerodynamic effectors for low-speed, high-alpha flight, with control levels that are a linear function of porous area. This work demonstrates the tremendous potential of passive porosity to yield simple control effector systems that have no external moving parts and will preserve an aircraft's fixed outer mold line.

  13. Virtual Welded - Joint Design Integrating Advanced Materials and Processing Technology

    SciTech Connect

    Yang, Zhishang; Ludewig, Howard W.; Babu, S. Suresh

    2005-06-30

    Virtual Welede-Joint Design, a systematic modeling approach, has been developed in this project to predict the relationship of welding process, microstructure, properties, residual stress, and the ultimate weld fatique strength. This systematic modeling approach was applied in the welding of high strength steel. A special welding wire was developed in this project to introduce compressive residual stress at weld toe. The results from both modeling and experiments demonstrated that more than 10x fatique life improvement can be acheived in high strength steel welds by the combination of compressive residual stress from the special welding wire and the desired weld bead shape from a unique welding process. The results indicate a technology breakthrough in the design of lightweight and high fatique performance welded structures using high strength steels.

  14. Sandia Advanced MEMS Design Tools, V2.1

    2002-02-04

    SUMMiT V (Sandia Ultra planar Multi level MEMS Technology) is a 5 level surface micromachine fabrication technology, which customers intornal and external to Sandia can access to fabricate prototype MEMS devices. This CD contains an integrated set of electronic files that: a) Describe the SUMMiT V fabrication process b) Provide enabling educational information (including pictures, videos, technical information) c) Facilitate the process of designing MEMS with the SUMMiT process (prototype file, Design Rule Checker, Standardmore » Parts Library) d) Facilitate the process of having MEMS fabricated at Sandia National Laboratories e) Facilitate the process of having post-fabrication services performed. While there exist some files on the CD that are used in conjunction with software package AutoCAD, these files are not intended for use independent of the CD. Nole that the customer must purchase his/her own copy of Aut0CAD to use with these files.« less

  15. Design, analysis, and test verification of advanced encapsulation systems

    NASA Technical Reports Server (NTRS)

    Mardesich, N.; Minning, C.

    1982-01-01

    Design sensitivities are established for the development of photovoltaic module criteria and the definition of needed research tasks. The program consists of three phases. In Phase I, analytical models were developed to perform optical, thermal, electrical, and structural analyses on candidate encapsulation systems. From these analyses several candidate systems will be selected for qualification testing during Phase II. Additionally, during Phase II, test specimens of various types will be constructed and tested to determine the validity of the analysis methodology developed in Phase I. In Phse III, a finalized optimum design based on knowledge gained in Phase I and II will be developed. All verification testing was completed during this period. Preliminary results and observations are discussed. Descriptions of the thermal, thermal structural, and structural deflection test setups are included.

  16. Design, analysis and test verification of advanced encapsulated systems

    NASA Astrophysics Data System (ADS)

    Garcia, A., III

    1985-11-01

    Methods have been developed to aid the photovoltaic manufacturer in the design of modules which will optimize the use of materials and method of manufacture for novel encapsulation schemes. Methods are described for using master curves to enable the design of modules which will withstand pressure loading from wind and/or precipitation as well as stress produced from diurnal and seasonal thermal cycling. Analysis methods using finite element modeling are presented to examine maximum electric field concentrations dependent on the geometry of cells and interconnects. Techniques for determining the operating temperature and optical efficiency of panels are presented. Several novel methods of manufacturing modules are described. Experimental results in the use of conductive polymers in photovoltaic cells as AR coatings, conductivity enhancers and passivation coatings are discussed.

  17. Advances in the physics basis for the European DEMO design

    NASA Astrophysics Data System (ADS)

    Wenninger, R.; Arbeiter, F.; Aubert, J.; Aho-Mantila, L.; Albanese, R.; Ambrosino, R.; Angioni, C.; Artaud, J.-F.; Bernert, M.; Fable, E.; Fasoli, A.; Federici, G.; Garcia, J.; Giruzzi, G.; Jenko, F.; Maget, P.; Mattei, M.; Maviglia, F.; Poli, E.; Ramogida, G.; Reux, C.; Schneider, M.; Sieglin, B.; Villone, F.; Wischmeier, M.; Zohm, H.

    2015-06-01

    In the European fusion roadmap, ITER is followed by a demonstration fusion power reactor (DEMO), for which a conceptual design is under development. This paper reports the first results of a coherent effort to develop the relevant physics knowledge for that (DEMO Physics Basis), carried out by European experts. The program currently includes investigations in the areas of scenario modeling, transport, MHD, heating & current drive, fast particles, plasma wall interaction and disruptions.

  18. Designing for Small Volume Assembly of Advanced Electronics Packages

    NASA Technical Reports Server (NTRS)

    Galbraith, L.; Bonner, J. K.

    1995-01-01

    We describe a general methodology to Design for Producibility and Reliability (DFPAR) for very small volume production runs. In cases where the entire volume for fabrication is less than five products, traditional Statistical Process Control (SPC) is inadequate due to reliance on statistics of much larger volumes and the Central Limit Theorem. Data acquisition for process parameter estimation from such a small sample size is difficult; however, it is critical to producing high reliability product.

  19. 7-GeV Advanced Photon Source Conceptual Design Report

    SciTech Connect

    Not Available

    1987-04-01

    During the past decade, synchrotron radiation emitted by circulating electron beams has come into wide use as a powerful, versatile source of x-rays for probing the structure of matter and for studying various physical processes. Several synchrotron radiation facilities with different designs and characteristics are now in regular operation throughout the world, with recent additions in this country being the 0.8-GeV and 2.5-GeV rings of NSLS at Brookhaven National Laboratory. However, none of the operating facilities has been designed to use a low-emittance, high-energy stored beam, together with modern undulator devices, to produce a large number of hard x-ray beams of extremely high brilliance. This document is a proposal to the Department of Energy to construct and operate high-energy synchrotron radiation facility at Argonne National Laboratory. We have now chosen to set the design energy of this facility at 7.0 GeV, with the capability to operate at up to 7.5 GeV.

  20. Advances in computational design and analysis of airbreathing propulsion systems

    NASA Technical Reports Server (NTRS)

    Klineberg, John M.

    1989-01-01

    The development of commercial and military aircraft depends, to a large extent, on engine manufacturers being able to achieve significant increases in propulsion capability through improved component aerodynamics, materials, and structures. The recent history of propulsion has been marked by efforts to develop computational techniques that can speed up the propulsion design process and produce superior designs. The availability of powerful supercomputers, such as the NASA Numerical Aerodynamic Simulator, and the potential for even higher performance offered by parallel computer architectures, have opened the door to the use of multi-dimensional simulations to study complex physical phenomena in propulsion systems that have previously defied analysis or experimental observation. An overview of several NASA Lewis research efforts is provided that are contributing toward the long-range goal of a numerical test-cell for the integrated, multidisciplinary design, analysis, and optimization of propulsion systems. Specific examples in Internal Computational Fluid Mechanics, Computational Structural Mechanics, Computational Materials Science, and High Performance Computing are cited and described in terms of current capabilities, technical challenges, and future research directions.

  1. Design advanced for large-scale, economic, floating LNG plant

    SciTech Connect

    Naklie, M.M.

    1997-06-30

    A floating LNG plant design has been developed which is technically feasible, economical, safe, and reliable. This technology will allow monetization of small marginal fields and improve the economics of large fields. Mobil`s world-scale plant design has a capacity of 6 million tons/year of LNG and up to 55,000 b/d condensate produced from 1 bcfd of feed gas. The plant would be located on a large, secure, concrete barge with a central moonpool. LNG storage is provided for 250,000 cu m and condensate storage for 650,000 bbl. And both products are off-loaded from the barge. Model tests have verified the stability of the barge structure: barge motions are low enough to permit the plant to continue operation in a 100-year storm in the Pacific Rim. Moreover, the barge is spread-moored, eliminating the need for a turret and swivel. Because the design is generic, the plant can process a wide variety of feed gases and operate in different environments, should the plant be relocated. This capability potentially gives the plant investment a much longer project life because its use is not limited to the life of only one producing area.

  2. Advanced turbine design for coal-fueled engines

    NASA Astrophysics Data System (ADS)

    Bornstein, N. S.

    1992-07-01

    The objective of this task is to perform a technical assessment of turbine blading for advanced second generation PFBC conditions, identify specific problems/issues, and recommend an approach for solving any problems identified. A literature search was conducted, problems associated with hot corrosion defined and limited experiments performed. Sulfidation corrosion occurs in industrial, marine and aircraft gas turbine engines and is due to the presence of condensed alkali (sodium) sulfates. The principle source of the alkali in industrial, marine and aircraft gas turbine engines is sea salt crystals. The principle source of the sulfur is not the liquid fuels, but the same ocean born crystals. Moreover deposition of the corrosive salt occurs primarily by a non-equilibrium process. Sodium will be present in the cleaned combusted gases that enter the PFBC turbine. Although equilibrium condensation is not favored, deposition via impaction is probable. Marine gas turbines operate in sodium chloride rich environments without experiencing the accelerated attack noted in coal fired boilers where condensed chlorides contact metallic surfaces. The sulfates of calcium and magnesium are the products of the reactions used to control sulfur. Based upon industrial gas turbine experience and laboratory tests, calcium and magnesium sulfates are, at temperatures up to 1500 F (815 C), relatively innocuous salts. In this study it is found that at 1650 F (900 C) and above, calcium sulfate becomes an aggressive corrodent.

  3. Advanced Control and Protection system Design Methods for Modular HTGRs

    SciTech Connect

    Ball, Sydney J; Wilson Jr, Thomas L; Wood, Richard Thomas

    2012-06-01

    The project supported the Nuclear Regulatory Commission (NRC) in identifying and evaluating the regulatory implications concerning the control and protection systems proposed for use in the Department of Energy's (DOE) Next-Generation Nuclear Plant (NGNP). The NGNP, using modular high-temperature gas-cooled reactor (HTGR) technology, is to provide commercial industries with electricity and high-temperature process heat for industrial processes such as hydrogen production. Process heat temperatures range from 700 to 950 C, and for the upper range of these operation temperatures, the modular HTGR is sometimes referred to as the Very High Temperature Reactor or VHTR. Initial NGNP designs are for operation in the lower temperature range. The defining safety characteristic of the modular HTGR is that its primary defense against serious accidents is to be achieved through its inherent properties of the fuel and core. Because of its strong negative temperature coefficient of reactivity and the capability of the fuel to withstand high temperatures, fast-acting active safety systems or prompt operator actions should not be required to prevent significant fuel failure and fission product release. The plant is designed such that its inherent features should provide adequate protection despite operational errors or equipment failure. Figure 1 shows an example modular HTGR layout (prismatic core version), where its inlet coolant enters the reactor vessel at the bottom, traversing up the sides to the top plenum, down-flow through an annular core, and exiting from the lower plenum (hot duct). This research provided NRC staff with (a) insights and knowledge about the control and protection systems for the NGNP and VHTR, (b) information on the technologies/approaches under consideration for use in the reactor and process heat applications, (c) guidelines for the design of highly integrated control rooms, (d) consideration for modeling of control and protection system designs for

  4. Low-noise submillimeter-wave NbTiN superconducting tunnel junction mixers

    NASA Astrophysics Data System (ADS)

    Kawamura, Jonathan; Chen, Jian; Miller, David; Kooi, Jacob; Zmuidzinas, Jonas; Bumble, Bruce; LeDuc, Henry G.; Stern, Jeff A.

    1999-12-01

    We have developed a low-noise 850 GHz superconductor-insulator-superconductor quasiparticle mixer with NbTiN thin-film microstrip tuning circuits and hybrid Nb/AlN/NbTiN tunnel junctions. The mixer uses a quasioptical configuration with a planar twin-slot antenna feeding a two-junction tuning circuit. At 798 GHz, we measured an uncorrected double-sideband receiver noise temperature of TRX=260 K at 4.2 K bath temperature. This mixer outperforms current Nb SIS mixers by a factor of nearly 2 near 800 GHz. The high-gap frequency and low loss at 800 GHz make NbTiN an attractive material with which to fabricate tuning circuits for SIS mixers. NbTiN mixers can potentially operate up to the gap frequency, 2Δ/h˜1.2 THz.

  5. Low-Noise Submillimeter-Wave NbTiN Superconducting Tunnel Junction Mixers

    NASA Technical Reports Server (NTRS)

    Kawamura, J.; Chen, J.; Miller, D.; Kooi, J.; Zmuidzinas, J.; Bumble, B.; LeDuc, H. G.; Stern, J. A.

    1999-01-01

    We have developed a low-noise 850 GHz superconductor-insulator-superconductor (SIS) quasi-particle mixer with NbTiN thin-film microstrip tuning circuits and hybrid Nb/AlN/NbTiN tunnel junctions. The mixer uses a quasioptical configuration with a planar twin-slot antenna feeding a two-junction tuning circuit. At 798 GHz, we measured an uncorrected double-sideband receiver noise temperature of T(sub RX) = 260 K at 4.2 K bath temperature. This mixer outperforms current Nb SIS mixers by a factor of nearly 2 near 800 GHz. The high gap frequency and low loss at 800 GHz make NbTiN an attractive material with which to fabricate tuning circuits for SIS mixers. NbTiN mixers can potentially operate up to the gap frequency, 2(delta)/h is approximately 1.2THz.

  6. NASA/USRA advanced design program, 1990 - 1991

    NASA Technical Reports Server (NTRS)

    1991-01-01

    Twenty-four UCLA students, in groups of four or five, participated in a mission design for a manned expedition to Mars that was based on the concept of mid-course refueling from electrically propelled tankers launched ahead of the manned mission. The study was conducted during the 1991 spring term. Some of the student groups opted for non-nuclear propulsion of the manned ship, based on LOX and LH2; others opted for one based on nuclear thermal propulsion. By way of example, the first option is presented here.

  7. Safety goals and functional performance criteria. [Advanced Reactor Design

    SciTech Connect

    Youngblood, R.W.; Pratt, W.T. ); Hardin, W.B. . Div. of Regulatory Applications)

    1990-01-01

    This report discusses a possible approach to the development of functional performance criteria to be applied to evolutionary LWR designs. Key safety functions are first identified; then, criteria are drawn up for each individual function, based on the premise that no single function's projected unreliability should be allowed to exhaust the safety goal frequencies. In the area of core damage prevention, functional criteria are cast in terms of necessary levels of redundancy and diversity of critical equipment. In the area of core damage mitigation (containment), functional performance criteria are cast with the aim of mitigating post-core-melt phenomena with sufficient assurance to eliminate major uncertainties in containment performance. 9 refs.

  8. Operational design factors for advanced space transportation vehicles

    NASA Astrophysics Data System (ADS)

    Whitehair, C. L.; Hickman, R. A.; Adams, J. D.; Wolfe, M. G.

    1992-08-01

    The tools and techniques needed to provide design decision-makers with balanced quantitative assessments of the potential operability consequences of their decisions are addressed. The factors controlling operability are identified, and a methodology to predict the impact of these factors on a specific launch vehicle is developed. Requirements to control these factors are established, and analytical tools developed specifically for performing detailed simulations to verify specific operability characteristics are described. An approach to collect, store, organize, and access high-quality historical, current, and future launch system data for the benefit of the USAF and the U.S. launch system community at large is outlined.

  9. An advanced open-path atmospheric monitor design

    SciTech Connect

    Taylor, L.; Suhre, D.; Mech, S.

    1996-05-01

    The conceptual design of an open-path atmospheric monitor combines an acousto-optic tunable filter for emission spectroscopy (3-14 {mu}m) with a mid-IR (4.6-5.4 {mu}m) for absorption spectroscopy. It utilizes mostly commercially available components, covers a large area ({approximately}4 km radius), measures the distance to any reflecting object, can take measurements along any line-of-sight, and is eye safe. Of twenty test pollutants it is to detect, the concentrations of all twenty will be measurable via emission spectroscopy and ten by the more sensitive absorption spectroscopy.

  10. Advanced multi-megawatt wind turbine design for utility application

    NASA Technical Reports Server (NTRS)

    Pijawka, W. C.

    1984-01-01

    A NASA/DOE program to develop a utility class multimegawatt wind turbine, the MOD-5A, is described. The MOD-5A features a 400 foot diameter rotor which is teetered and positioned upwind of the tower; a 7.3 megawatt power rating with a variable speed electric generating system; and a redundant rotor support and torque transmission structure. The rotor blades were fabricated from an epoxy-bonded wood laminate material which was a successful outgrowth of the MOD-OA airfoil design. Preliminary data from operational tests carried out at the NASA Plumbrook test facility are presented.

  11. Advanced vehicle concepts systems and design analysis studies

    NASA Technical Reports Server (NTRS)

    Waters, Mark H.; Huynh, Loc C.

    1994-01-01

    The work conducted by the ELORET Institute under this Cooperative Agreement includes the modeling of hypersonic propulsion systems and the evaluation of hypersonic vehicles in general and most recently hypersonic waverider vehicles. This work in hypersonics was applied to the design of a two-stage to orbit launch vehicle which was included in the NASA Access to Space Project. Additional research regarded the Oblique All-Wing (OAW) Project at NASA ARC and included detailed configuration studies of OAW transport aircraft. Finally, work on the modeling of subsonic and supersonic turbofan engines was conducted under this research program.

  12. An Integrated Framework Advancing Membrane Protein Modeling and Design

    PubMed Central

    Weitzner, Brian D.; Duran, Amanda M.; Tilley, Drew C.; Elazar, Assaf; Gray, Jeffrey J.

    2015-01-01

    Membrane proteins are critical functional molecules in the human body, constituting more than 30% of open reading frames in the human genome. Unfortunately, a myriad of difficulties in overexpression and reconstitution into membrane mimetics severely limit our ability to determine their structures. Computational tools are therefore instrumental to membrane protein structure prediction, consequently increasing our understanding of membrane protein function and their role in disease. Here, we describe a general framework facilitating membrane protein modeling and design that combines the scientific principles for membrane protein modeling with the flexible software architecture of Rosetta3. This new framework, called RosettaMP, provides a general membrane representation that interfaces with scoring, conformational sampling, and mutation routines that can be easily combined to create new protocols. To demonstrate the capabilities of this implementation, we developed four proof-of-concept applications for (1) prediction of free energy changes upon mutation; (2) high-resolution structural refinement; (3) protein-protein docking; and (4) assembly of symmetric protein complexes, all in the membrane environment. Preliminary data show that these algorithms can produce meaningful scores and structures. The data also suggest needed improvements to both sampling routines and score functions. Importantly, the applications collectively demonstrate the potential of combining the flexible nature of RosettaMP with the power of Rosetta algorithms to facilitate membrane protein modeling and design. PMID:26325167

  13. Advances and Computational Tools towards Predictable Design in Biological Engineering

    PubMed Central

    2014-01-01

    The design process of complex systems in all the fields of engineering requires a set of quantitatively characterized components and a method to predict the output of systems composed by such elements. This strategy relies on the modularity of the used components or the prediction of their context-dependent behaviour, when parts functioning depends on the specific context. Mathematical models usually support the whole process by guiding the selection of parts and by predicting the output of interconnected systems. Such bottom-up design process cannot be trivially adopted for biological systems engineering, since parts function is hard to predict when components are reused in different contexts. This issue and the intrinsic complexity of living systems limit the capability of synthetic biologists to predict the quantitative behaviour of biological systems. The high potential of synthetic biology strongly depends on the capability of mastering this issue. This review discusses the predictability issues of basic biological parts (promoters, ribosome binding sites, coding sequences, transcriptional terminators, and plasmids) when used to engineer simple and complex gene expression systems in Escherichia coli. A comparison between bottom-up and trial-and-error approaches is performed for all the discussed elements and mathematical models supporting the prediction of parts behaviour are illustrated. PMID:25161694

  14. An Integrated Framework Advancing Membrane Protein Modeling and Design.

    PubMed

    Alford, Rebecca F; Koehler Leman, Julia; Weitzner, Brian D; Duran, Amanda M; Tilley, Drew C; Elazar, Assaf; Gray, Jeffrey J

    2015-09-01

    Membrane proteins are critical functional molecules in the human body, constituting more than 30% of open reading frames in the human genome. Unfortunately, a myriad of difficulties in overexpression and reconstitution into membrane mimetics severely limit our ability to determine their structures. Computational tools are therefore instrumental to membrane protein structure prediction, consequently increasing our understanding of membrane protein function and their role in disease. Here, we describe a general framework facilitating membrane protein modeling and design that combines the scientific principles for membrane protein modeling with the flexible software architecture of Rosetta3. This new framework, called RosettaMP, provides a general membrane representation that interfaces with scoring, conformational sampling, and mutation routines that can be easily combined to create new protocols. To demonstrate the capabilities of this implementation, we developed four proof-of-concept applications for (1) prediction of free energy changes upon mutation; (2) high-resolution structural refinement; (3) protein-protein docking; and (4) assembly of symmetric protein complexes, all in the membrane environment. Preliminary data show that these algorithms can produce meaningful scores and structures. The data also suggest needed improvements to both sampling routines and score functions. Importantly, the applications collectively demonstrate the potential of combining the flexible nature of RosettaMP with the power of Rosetta algorithms to facilitate membrane protein modeling and design. PMID:26325167

  15. Design of radiation resistant metallic multilayers for advanced nuclear systems

    SciTech Connect

    Zhernenkov, Mikhail E-mail: gills@bnl.gov; Gill, Simerjeet E-mail: gills@bnl.gov; Stanic, Vesna; DiMasi, Elaine; Kisslinger, Kim; Ecker, Lynne; Baldwin, J. Kevin; Misra, Amit; Demkowicz, M. J.

    2014-06-16

    Helium implantation from transmutation reactions is a major cause of embrittlement and dimensional instability of structural components in nuclear energy systems. Development of novel materials with improved radiation resistance, which is of the utmost importance for progress in nuclear energy, requires guidelines to arrive at favorable parameters more efficiently. Here, we present a methodology that can be used for the design of radiation tolerant materials. We used synchrotron X-ray reflectivity to nondestructively study radiation effects at buried interfaces and measure swelling induced by He implantation in Cu/Nb multilayers. The results, supported by transmission electron microscopy, show a direct correlation between reduced swelling in nanoscale multilayers and increased interface area per unit volume, consistent with helium storage in Cu/Nb interfaces in forms that minimize dimensional changes. In addition, for Cu/Nb layers, a linear relationship is demonstrated between the measured depth-dependent swelling and implanted He density from simulations, making the reflectivity technique a powerful tool for heuristic material design.

  16. [Advances in the Immunogenic Design of HIV-1 Vaccine].

    PubMed

    Zhang, Xiaohong; Wang, Tao; Yu, Xiaofang

    2016-01-01

    A safe and effective vaccine against the human immunodeficiency virus type 1 (HIV-1) is expected to have a considerable impact on elimination of acquired immune deficiency syndrome. Despite decades of effort, an effective vaccine against HIV-1 remains elusive. In recent years, the Thai HIV Vaccine Efficacy Trial (known as RV144) showed a reduction in HIV-1 acquisition by 31%, but this agent could not delay disease progression in vaccinated individuals. Clinical analyses of experimental data and experiments in vitro have revealed two main types of immunogen design: induction of broad-spectrum neutralizing antibody (bNAb) and cytotoxic T lymphocyte (CTL) responses. bNAb can prevent or reduce acquisition of infection, and its main immunogens are virus-like particles, natural envelope trimers and stable bNAb epitopes. An effective CTL response can slow-down viral infection, and its main immunogens are "mosaic" vaccines, "conserved immunogens", and the "fitness landscape" of HIV-1 proteins. This review summarizes the strategies as well as progress in the design and testing of HIV-1 immunogens to elicit bNAb and CTL responses. PMID:27295889

  17. Wide-band operation of quasi-optical distributed superconductor/insulator/superconductor mixers with epitaxial NbN/AlN/NbN junctions

    NASA Astrophysics Data System (ADS)

    Kohjiro, S.; Shitov, S. V.; Wang, Z.; Uzawa, Y.; Miki, S.; Kawakami, A.; Shoji, A.

    2004-05-01

    For the optimum design of integrated receivers operating above the gap frequency of Nb, we have designed, fabricated and tested NbN-based quasi-optical superconductor/insulator/superconductor (SIS) mixers. The mixer chip incorporates a resonant half-wavelength epitaxial NbN/AlN/NbN junction, a twin-slot antenna and their coupling circuits. We adopted two kinds of coupling circuit between the antenna and the SIS junction: one is an in-phase feed with a length of 95 µm and the other is an anti-phase feed of 30 µm length. It was found that the anti-phase mixer reveals a 3 dB bandwidth of 43% of the centre frequency; the uncorrected double-sideband receiver noise temperature TRX = 691 K at 0.91 THz and TRX = 844 K at 0.80 THz, while 17% and TRX = 1250 K at 0.79 THz for the in-phase version. Possible reasons for this difference are discussed, which could be transmission loss and its robustness with respect to the variation of junction parameters. These experimental results suggest the NbN-based distributed mixer with the anti-phase feed is a better candidate for wide-band integrated receivers operating above 0.7 THz.

  18. Self-Anchoring Mast for Deploying a High-Speed Submersible Mixer in a Tank

    SciTech Connect

    Cato, Joseph E. Jr.; Shearer, Paul M.; Rodwell, Philip 0.

    2004-10-12

    A self-anchoring mast for deploying a high-speed submersible mixer in a tank includes operably connected first and second mast members (20, 22) and a foot member 46 operably connected to the second mast member for supporting the mast in a tank. The second mast member includes a track (36, 38) for slidably receiving a bearing of the mixer to change the orientation of the mixer in the tank.

  19. An integrated membrane sub-harmonic Schottky diode mixers at 340GHz

    NASA Astrophysics Data System (ADS)

    Wang, Junlong; Yang, Dabao; Xing, Dong; Liang, Shixiong; Zhang, Lisen; Zhao, Xiangyang; Feng, Zhihong

    2015-11-01

    This paper presents a sub-harmonic mixer operating over the spectral band 332-348 GHz. The mixers employ integrated GaAs membrane Schottky diode technology. The simulated results show that the conversion loss of the mixer is below dB in the band from 333 GHz to 347 GHz with a local oscillator power requirement of 5mW.The minimum is 8.2dB at 344GHz.

  20. Self-anchoring mast for deploying a high-speed submersible mixer in a tank

    DOEpatents

    Cato, Jr., Joseph E.; Shearer, Paul M.; Rodwell, Philip O.

    2004-10-12

    A self-anchoring mast for deploying a high-speed submersible mixer in a tank includes operably connected first and second mast members (20, 22) and a foot member 46 operably connected to the second mast member for supporting the mast in a tank. The second mast member includes a track (36, 38) for slidably receiving a bearing of the mixer to change the orientation of the mixer in the tank.