WorldWideScience

Sample records for vibrationless rotary coupling

  1. Fluidized bed coupled rotary reactor for nanoparticles coating via atomic layer deposition

    Energy Technology Data Exchange (ETDEWEB)

    Duan, Chen-Long; Liu, Xiao; Chen, Rong, E-mail: rongchen@mail.hust.edu.cn, E-mail: bshan@mail.hust.edu.cn [State Key Laboratory of Digital Manufacturing Equipment and Technology, School of Mechanical Science and Engineering, Huazhong University of Science and Technology, 1037 Luoyu Road, Wuhan, Hubei 430074 (China); Shan, Bin, E-mail: rongchen@mail.hust.edu.cn, E-mail: bshan@mail.hust.edu.cn [State Key Laboratory of Material Processing and Die & Mould Technology, School of Materials Science and Engineering, Huazhong University of Science and Technology, 1037 Luoyu Road, Wuhan, Hubei 430074 (China)

    2015-07-15

    A fluidized bed coupled rotary reactor has been designed for coating on nanoparticles (NPs) via atomic layer deposition. It consists of five major parts: reaction chamber, dosing and fluidizing section, pumping section, rotary manipulator components, as well as a double-layer cartridge for the storage of particles. In the deposition procedure, continuous fluidization of particles enlarges and homogenizes the void fraction in the particle bed, while rotation enhances the gas-solid interactions to stabilize fluidization. The particle cartridge presented here enables both the fluidization and rotation acting on the particle bed, demonstrated by the analysis of pressure drop. Moreover, enlarged interstitials and intense gas–solid contact under sufficient fluidizing velocity and proper rotation speed facilitate the precursor delivery throughout the particle bed and consequently provide a fast coating process. The cartridge can ensure precursors flowing through the particle bed exclusively to achieve high utilization without static exposure operation. By optimizing superficial gas velocities and rotation speeds, minimum pulse time for complete coating has been shortened in experiment, and in situ mass spectrometry showed the precursor usage can reach 90%. Inductively coupled plasma-optical emission spectroscopy results suggested a saturated growth of nanoscale Al{sub 2}O{sub 3} films on spherical SiO{sub 2} NPs. Finally, the uniformity and composition of the shells were characterized by high angle annular dark field-transmission electron microscopy and energy dispersive X-ray spectroscopy.

  2. Novel Plasma Reactor with Rotary Helix Electrode Used in Coupling of CH4 at Atmospheric Pressure

    International Nuclear Information System (INIS)

    Wang Dawang; Ma Tengcai

    2006-01-01

    At the ambient temperature and pressure a glow discharge plasma was used as a new approach for the coupling of methane with the newly-developed rotary multidentate helix electrode. In the presence of hydrogen, the effects of the input peak voltages and gas flow rates on methane conversion, C 2 single pass yield and selectivity were investigated, and then the results were compared with those from the three-disc multidentate electrode. This demonstrated, on an experimental scale, that the rotary multidentate helix electrode was better than the multidentate three-disc electrode as there was little accumulation of coke, and the C 2 yield per pass was 69.85% and C 2 selectivity over 99.14% with 70.46% methane conversion at an input peak voltage of 2300 V and 60 ml/min gas flow rate

  3. Methods and apparatus for controlling rotary machines

    Science.gov (United States)

    Bagepalli, Bharat Sampathkumaran [Niskayuna, NY; Jansen, Patrick Lee [Scotia, NY; Barnes, Gary R [Delanson, NY; Fric, Thomas Frank [Greer, SC; Lyons, James Patrick Francis [Niskayuna, NY; Pierce, Kirk Gee [Simpsonville, SC; Holley, William Edwin [Greer, SC; Barbu, Corneliu [Guilderland, NY

    2009-09-01

    A control system for a rotary machine is provided. The rotary machine has at least one rotating member and at least one substantially stationary member positioned such that a clearance gap is defined between a portion of the rotating member and a portion of the substantially stationary member. The control system includes at least one clearance gap dimension measurement apparatus and at least one clearance gap adjustment assembly. The adjustment assembly is coupled in electronic data communication with the measurement apparatus. The control system is configured to process a clearance gap dimension signal and modulate the clearance gap dimension.

  4. Measurements of noise from rotary coal unloading operations

    International Nuclear Information System (INIS)

    Adams, T.S.; Bilello, M.A.

    1991-01-01

    In the licensing effort for a coal-fired power plant in the northeast United States, noise related to delivery and unloading of coal by train was identified as a significant concern to the nearby community. Specific issues included locomotive noise, the banging noises caused by railcar couplings during the start and stop cycles of the unloading operation, wheel squeal in the curves of the rail loop, and rotary coal unloader noises. This paper reports that a literature review provided adequate information on idling locomotive noise but very little on the other noise sources. Coupling impact noise was well documented for railcars actually being coupled at various speeds but not for coupled trains during start and stop operations. Wheel squeal was well documented by subway trains travelling at normal speeds, but nothing could be found for wheel squeal during very slow train movement as occurs during unloading. Similarly, adequate information was available for unenclosed rotary unloaders but not for enclosed unloaders. Consequently, actual noise measurements of a similar enclosed facility, and the associated train movements, were undertaken to obtain data more directly applicable to the planned facility

  5. Ultrasonic rotary-hammer drill

    Science.gov (United States)

    Bar-Cohen, Yoseph (Inventor); Badescu, Mircea (Inventor); Sherrit, Stewart (Inventor); Bao, Xiaoqi (Inventor); Kassab, Steve (Inventor)

    2010-01-01

    A mechanism for drilling or coring by a combination of sonic hammering and rotation. The drill includes a hammering section with a set of preload weights mounted atop a hammering actuator and an axial passage through the hammering section. In addition, a rotary section includes a motor coupled to a drive shaft that traverses the axial passage through the hammering section. A drill bit is coupled to the drive shaft for drilling by a combination of sonic hammering and rotation. The drill bit includes a fluted shaft leading to a distal crown cutter with teeth. The bit penetrates sampled media by repeated hammering action. In addition, the bit is rotated. As it rotates the fluted bit carries powdered cuttings helically upward along the side of the bit to the surface.

  6. Rotary Compressor Noise Analysis Using Mechanisms and Electromagnetics Coupled Approach

    OpenAIRE

    Chung, Jinah; Lee, Uiyoon; Lee, Jeongbae; Lee, Unseop; Han, Eunsil; Yoon, Jinhwan

    2016-01-01

    This research is conducted to investigate noise source and design low noise compressors. For improving energy efficiency, the rotary compressor with variable speed brushless DC motor is increasingly adopted for appliances. However brushless DC motor makes more compressor vibration than constant speed motor compressor at high speed operating condition. Therefore it is necessary to reduce noise and vibration for improving air conditioner quality. In this study, compressor’s noise and vibrat...

  7. A dual resonant rectilinear-to-rotary oscillation converter for low frequency broadband electromagnetic energy harvesting

    Science.gov (United States)

    Deng, Wei; Wang, Ya

    2017-09-01

    This paper reports a dual resonant rectilinear-to-rotary oscillation converter (RROC) for low frequency broadband electromagnetic energy harvesting from ambient vibrations. An approximate theoretical model has been established to integrate the electromechanical coupling into a comprehensive electromagnetic-dynamic model of the dual resonant RROC. Numerical simulation has proved the nature of dual resonances by revealing that both the rectilinear resonance and the rotary resonance could be achieved when the stand-alone rectilinear oscillator (RLO) and the stand-alone rotary oscillator (RTO) were excited independently. Simulation on the magnetically coupled RROC has also shown that the rectilinear resonance and the rotary resonance could be obtained simultaneously in the low-frequency region (2-14 Hz) with well-defined restoring torque (M r ) and the initial rotation angle of the RLO (ψ). The magnetic interaction patterns between the rectilinear and the RTOs have been categorized based on aforementioned simulation results. Both simulation and experimental results have demonstrated broadband output attributing from the dual resonances. Experimental results have also indicated that the RROC could have wide bandwidth in a much lower frequency region (2-8 Hz) even without the rotary resonance as long as the system parameters are carefully tuned. Parameter analysis on different values of M r and ψ are experimentally carried out to provide a quantitative guidance of designing the RROC to achieve an optimal power density.

  8. Advanced rotary engines

    Science.gov (United States)

    Jones, C.

    1983-01-01

    The broad objectives of this paper are the following: (1) to summarize the Curtiss-Wright design, development and field testing background in the area of rotary aircraft engines; (2) to briefly summarize past activity and update development work in the area of stratified charge rotary combustion engines; and (3) to discuss the development of a high-performance direct injected unthrottled stratified charge rotary combustion aircraft engine. Efficiency improvements through turbocharging are also discussed.

  9. Rotary deformity in degenerative spondylolisthesis

    International Nuclear Information System (INIS)

    Kang, Sung Gwon; Kim, Jeong; Kho, Hyen Sim; Yun, Sung Su; Oh, Jae Hee; Byen, Ju Nam; Kim, Young Chul

    1994-01-01

    We studied to determine whether the degenerative spondylolisthesis has rotary deformity in addition to forward displacement. We have made analysis of difference of rotary deformity between the 31 study groups of symptomatic degenerative spondylolisthesis and 31 control groups without any symptom, statistically. We also reviewed CT findings in 15 study groups. The mean rotary deformity in study groups was 6.1 degree(the standard deviation is 5.20), and the mean rotary deformity in control groups was 2.52 degree(the standard deviation is 2.16)(p < 0.01). The rotary deformity can be accompanied with degenerative spondylolisthesis. We may consider the rotary deformity as a cause of symptomatic degenerative spondylolisthesis in case that any other cause is not detected

  10. Multifuel rotary aircraft engine

    Science.gov (United States)

    Jones, C.; Berkowitz, M.

    1980-01-01

    The broad objectives of this paper are the following: (1) to summarize the Curtiss-Wright design, development and field testing background in the area of rotary aircraft engines; (2) to briefly summarize past activity and update development work in the area of stratified charge rotary combustion engines; and (3) to discuss the development of a high-performance direct injected unthrottled stratified charge rotary combustion aircraft engine. Efficiency improvements through turbocharging are also discussed.

  11. Rotary combustion device

    NARCIS (Netherlands)

    2008-01-01

    Rotary combustion device (1) with rotary combustion chamber (4). Specific measures are taken to provide ignition of a combustible mixture. It is proposed that a hollow tube be provided coaxially with the axis of rotation (6), so that a small part of the mixture is guided into the combustion chamber.

  12. Rotary Transformer

    Science.gov (United States)

    McLyman, Colonel Wm. T.

    1996-01-01

    None given. From first Par: Many spacecraft (S/C) and surface rovers require the transfer of signals and power across rotating interfaces. Science instruments, antennas and solar arrays are elements needing rotary power transfer for certain (S/C) configurations. Delivery of signal and power has mainly been done by using the simplest means, the slip ring approach. This approach, although simple, leaves debris generating noise over a period of time...The rotary transformer is a good alternative to slip rings for signal and power transfer.

  13. Omega-X micromachining system

    International Nuclear Information System (INIS)

    Miller, D.M.

    1978-01-01

    A micromachining tool system with X- and omega-axes is used to machine spherical, aspherical, and irregular surfaces with a maximum contour error of 100 nonometers (nm) and surface waviness of no more than 0.8 nm RMS. The omega axis, named for the angular measurement of the rotation of an eccentric mechanism supporting one end of a tool bar, enables the pulse increments of the tool toward the workpiece to be as little as 0 to 4.4 nm. A dedicated computer coordinates motion in the two axes to produce the workpiece contour. Inertia is reduced by reducing the mass pulsed toward the workpiece to about one-fifth of its former value. The tool system includes calibration instruments to calibrate the micromachining tool system. Backlash is reduced and flexing decreased by using a rotary table and servomotor to pulse the tool in the omega-axis instead of a ball screw mechanism. A thermally-stabilized spindle roates the workpiece and is driven by a motor not mounted on the micromachining tool base through a torque-smoothing pulley and vibrationless rotary coupling. Abbe offset errors are almost eliminated by tool setting and calibration at spindle center height. Tool contour and workpiece contour are gaged on the machine; this enables the source of machining errors to be determined more readily, because the workpiece is gaged before its shape can be changed by removal from the machine

  14. Omnidirectional Wireless Power Transfer System Based on Rotary Transmitting Coil for Household Appliances

    Directory of Open Access Journals (Sweden)

    Gongjun Liu

    2018-04-01

    Full Text Available An omnidirectional magnetically coupled resonant wireless power transfer (WPT system based on rotary transmitting coil is presented. The proposed scheme can ease the variations of the transfer efficiency and output power caused by the deviation of transfer direction, and improve the unbalanced power distribution phenomenon between the receivers, which are still not fully achieved in current WPT systems. The modified coupled-mode model is built first to describe the non-rotary multi-receiver WPT system. The analysis indicates that the transfer efficiency and output power of the system can be expressed as functions of the deviation angle between the transmitting coil and receiving coil, which has a non-negligible influence on the system performances. Then, the modified high order coupled-mode model containing time-varying parameters about the deviation angle is derived for the proposed omnidirectional WPT system. Theoretical analysis and simulated results indicate that this system can transfer power to multiple receivers around the transmitter synchronously and evenly, which is very suitable for wireless charging for household appliances indoors. The scheme feasibility and theoretical analysis are verified by experimental results.

  15. Atomic layer deposition on nanoparticles in a rotary reactor

    Science.gov (United States)

    McCormick, Jarod Alan

    Challenges are encountered during atomic layer deposition (ALD) on large quantities of nanoparticles. The particles must be agitated or vigorously mixed to perform the ALD surface reactions in reasonable times and to prevent the particles from being agglomerated by the ALD film. The high surface area of nanoparticles also demands efficient reactant usage because large quantities of reactant are required for the surface reactions to reach completion. To address these challenges, a novel rotary reactor was developed to achieve constant particle agitation during static ALD reactant exposures. In the design of this new reactor, a cylindrical drum with porous metal walls was positioned inside a vacuum chamber. The porous cylindrical drum was rotated by a magnetically coupled rotary feedthrough. By rotating the cylindrical drum to obtain a centrifugal force of less than one gravitational force, the particles were agitated by a continuous "avalanche" of particles. The effectiveness of this rotary reactor was demonstrated by Al 2O3 ALD on ZrO2 particles. A number of techniques including transmission electron microscopy, Fourier transform infrared spectroscopy, scanning Auger spectroscopy and x-ray photoelectron spectroscopy confirmed that the Al2O3 ALD film conformally coats the ZrO 2 particles. Combining static reactant exposures with a very high surface area sample in the rotary reactor also provides unique opportunities for studying the surface chemistry during ALD. Sequential, subsaturating doses can be used to examine the self-limiting behavior of the ALD reactions in the rotary reactor. This dosing method is the first demonstration of self-limiting ALD on bulk quantities of nanoparticles. By combining these sequential, subsaturating doses with quadrupole mass spectrometry, ALD reactions can be analyzed from the gas phase using full mass spectrum analysis. The reaction products are present in a high enough concentration to discern a gas phase mechanism for reactions

  16. An Improved Rotary Interpolation Based on FPGA

    Directory of Open Access Journals (Sweden)

    Mingyu Gao

    2014-08-01

    Full Text Available This paper presents an improved rotary interpolation algorithm, which consists of a standard curve interpolation module and a rotary process module. Compared to the conventional rotary interpolation algorithms, the proposed rotary interpolation algorithm is simpler and more efficient. The proposed algorithm was realized on a FPGA with Verilog HDL language, and simulated by the ModelSim software, and finally verified on a two-axis CNC lathe, which uses rotary ellipse and rotary parabolic as an example. According to the theoretical analysis and practical process validation, the algorithm has the following advantages: firstly, less arithmetic items is conducive for interpolation operation; and secondly the computing time is only two clock cycles of the FPGA. Simulations and actual tests have proved that the high accuracy and efficiency of the algorithm, which shows that it is highly suited for real-time applications.

  17. Miniaturization limitations of rotary internal combustion engines

    International Nuclear Information System (INIS)

    Wang, Wei; Zuo, Zhengxing; Liu, Jinxiang

    2016-01-01

    Highlights: • Developed a phenomenological model for rotary internal combustion engines. • Presented scaling laws for the performance of micro rotary engines. • Adiabatic walls can improve the cycle efficiency but result in higher charge leakage. • A lower compression ratio can increase the efficiency due to lower mass losses. • Presented possible minimum engine size of rotary internal combustion engines. - Abstract: With the rapid development of micro electro-mechanical devices, the demands for micro power generation systems have significantly increased in recent years. Traditional chemical batteries have energy densities much lower than hydrocarbon fuels, which makes internal-combustion-engine an attractive technological alternative to batteries. Micro rotary internal combustion engine has drawn great attractions due to its planar design, which is well-suited for fabrication in MEMS. In this paper, a phenomenological model considering heat transfer and mass leakage has been developed to investigate effects of engine speed, compression ratio, blow-by and heat transfer on the performance of micro rotary engine, which provide the guidelines for preliminary design of rotary engine. The lower possible miniaturization limits of rotary combustion engines are proposed.

  18. Advanced rotary engine studies

    Science.gov (United States)

    Jones, C.

    1980-01-01

    A review of rotary engine developments relevant to a stratified charge rotary aircraft engine is presented. Advantages in module size and weight, fuel efficiency, reliability, and multi-fuel capability are discussed along with developments in turbocharging, increased mean effective pressure, improved apex seal/trochoid wear surfacing materials, and high strength and temperature aluminum casting alloys. A carbureted prototype aircraft engine is also described.

  19. ProTaper rotary instrument fracture during root canal preparation: a comparison between rotary and hybrid techniques.

    Science.gov (United States)

    Farid, Huma; Khan, Farhan Raza; Rahman, Munawar

    2013-03-01

    This study aimed to compare the frequency of ProTaper rotary instrument fracture with rotary (conventional) and hybrid (rotary and hand files) canal preparation techniques. Secondary objectives were to determine whether there was an association of ProTaper file fracture with the canal curvature and to compare the mean time required for canal preparation in the two techniques. An in vitro experiment was conducted on 216 buccal canals of extracted maxillary and mandibular first molars. After creating an access cavity and a glide path for each canal, a periapical radiograph was taken and the canal curvature was measured with Schneider's technique. The canals were then randomly divided into Group A (rotary technique) and Group B (hybrid technique). The length of ProTaper files were measured before and after each canal preparation. Time taken for each canal preparation was recorded. A total of seven ProTaper files fractured in Group A (P=0.014) in canals with a curvature >25 degrees (PProTaper rotary files, although time consuming, was safer in canals having a curvature greater than 25 degrees.

  20. Development of a Piezoelectric Rotary Hammer Drill

    Science.gov (United States)

    Domm, Lukas N.

    2011-01-01

    The Piezoelectric Rotary Hammer Drill is designed to core through rock using a combination of rotation and high frequency hammering powered by a single piezoelectric actuator. It is designed as a low axial preload, low mass, and low power device for sample acquisition on future missions to extraterrestrial bodies. The purpose of this internship is to develop and test a prototype of the Piezoelectric Rotary Hammer Drill in order to verify the use of a horn with helical or angled cuts as a hammering and torque inducing mechanism. Through an iterative design process using models in ANSYS Finite Element software and a Mason's Equivalent Circuit model in MATLAB, a horn design was chosen for fabrication based on the predicted horn tip motion, electromechanical coupling, and neutral plane location. The design was then machined and a test bed assembled. The completed prototype has proven that a single piezoelectric actuator can be used to produce both rotation and hammering in a drill string through the use of a torque inducing horn. Final data results include bit rotation produced versus input power, and best drilling rate achieved with the prototype.

  1. BIOMATERIALS FOR ROTARY BLOOD PUMPS

    NARCIS (Netherlands)

    VANOEVEREN, W

    Rotary blood pumps are used for cardiac assist and cardiopulmonary support since mechanical blood damage is less than with conventional roller pumps. The high shear rate in the rotary pump and the reduced anticoagulation of the patient during prolonged pumping enforces high demands on the

  2. Floating seal system for rotary devices

    Science.gov (United States)

    Banasiuk, H.A.

    1983-08-23

    This invention relates to a floating seal system for rotary devices to reduce gas leakage around the rotary device in a duct and across the face of the rotary device to an adjacent duct. The peripheral seal bodies are made of resilient material having a generally U-shaped cross section wherein one of the legs is secured to a support member and the other of the legs forms a contacting seal against the rotary device. The legs of the peripheral seal form an extended angle of intersection of about 10[degree] to about 30[degree] in the unloaded condition to provide even sealing forces around the periphery of the rotary device. The peripheral seal extends around the periphery of the support member except where intersected by radial seals which reduce gas leakage across the face of the rotary device and between adjacent duct portions. The radial seal assembly is fabricated from channel bars, the smaller channel bar being secured to the divider of the support member and a larger inverted rigid floating channel bar having its legs freely movable over the legs of the smaller channel bar forming therewith a tubular channel. A resilient flexible tube is positioned within the tubular channel for substantially its full length to reduce gas leakage across the tubular channel. A spacer extends beyond the face of the floating channel near each end of the floating channel a distance to provide desired clearance between the floating channel and the face of the rotary device. 5 figs.

  3. Rotary mechanical latch

    Science.gov (United States)

    Spletzer, Barry L.; Martinez, Michael A.; Marron, Lisa C.

    2012-11-13

    A rotary mechanical latch for positive latching and unlatching of a rotary device with a latchable rotating assembly having a latching gear that can be driven to latched and unlatched states by a drive mechanism such as an electric motor. A cam arm affixed to the latching gear interfaces with leading and trailing latch cams affixed to a flange within the drive mechanism. The interaction of the cam arm with leading and trailing latch cams prevents rotation of the rotating assembly by external forces such as those due to vibration or tampering.

  4. Capacity control of rotary vane apparatus

    International Nuclear Information System (INIS)

    Roberts, R. W.

    1985-01-01

    A capacity control arrangement for a rotary vane fluid displacement apparatus, such as a rotary vane compressor, having a vane retaining means that normally engages and retains the vanes in their retracted or nonworking position within the rotor defined guide slits of such rotary vane compressor. The retaining means are actuated to the vane-disengaged position by hydraulic control fluid which is communicated to the retaining means in response to an external parameter sensed by a control means

  5. Rotary-atomizer electric power generator

    NARCIS (Netherlands)

    Nguyen, Trieu; Tran, Tuan; de Boer, Hans L.; van den Berg, Albert; Eijkel, Jan C.T.

    2015-01-01

    We report experimental and theoretical results on a ballistic energy-conversion method based on a rotary atomizer working with a droplet acceleration-deceleration cycle. In a rotary atomizer, liquid is fed onto the center of a rotating flat surface, where it spreads out under the action of the

  6. Rotary engine research

    Science.gov (United States)

    1992-06-01

    A development history is presented for NASA's 1983-1991 Rotary Engine Enablement Program, emphasizing the CFD approaches to various problems that were instituted from 1987 to the end of the program. In phase I, a test rig was built to intensively clarify and characterize the stratified-charge rotary engine concept. In phase II, a high pressure, electronically controlled fuel injection system was tested. In phase III, the testing of improved fuel injectors led to the achievement of the stipulated 5 hp/cu inch specific power goal. CFD-aided design of advanced rotor-pocket shapes led to additional performance improvements.

  7. Rotary Power Transformer and Inverter Circuit

    Science.gov (United States)

    Mclyman, C. W. T.; Bridgeforth, A. O.

    1985-01-01

    Noise lower than with sliprings. Rotary transformer transfers electric power across rotary joint. No wearing contacts, no contact noise, and no contamination from lubricants or wear debris. Because additional inductor not required, size and complexity of circuit reduced considerably.

  8. 21 CFR 872.4840 - Rotary scaler.

    Science.gov (United States)

    2010-04-01

    ... DENTAL DEVICES Surgical Devices § 872.4840 Rotary scaler. (a) Identification. A rotary scaler is an abrasive device intended to be attached to a powered handpiece to remove calculus deposits from teeth during dental cleaning and periodontal (gum) therapy. (b) Classification. Class II. ...

  9. Fluid powered linear piston motor with harmonic coupling

    Science.gov (United States)

    Raymond, David W.

    2016-09-20

    A motor is disclosed that includes a module assembly including a piston that is axially cycled. The piston axial motion is coupled to torque couplers that convert the axial motion into rotary motion. The torque couplers are coupled to a rotor to rotate the rotor.

  10. A Comparison of Apical Bacterial Extrusion in Manual, ProTaper Rotary, and One Shape Rotary Instrumentation Techniques.

    Science.gov (United States)

    Mittal, Rakesh; Singla, Meenu G; Garg, Ashima; Dhawan, Anu

    2015-12-01

    Apical extrusion of irrigants and debris is an inherent limitation associated with cleaning and shaping of root canals and has been studied extensively because of its clinical relevance as a cause of flare-ups. Many factors affect the amount of extruded intracanal materials. The purpose of this study was to assess the bacterial extrusion by using manual, multiple-file continuous rotary system (ProTaper) and single-file continuous rotary system (One Shape). Forty-two human mandibular premolars were inoculated with Enterococcus faecalis by using a bacterial extrusion model. The teeth were divided into 3 experimental groups (n = 12) and 1 control group (n = 6). The root canals of experimental groups were instrumented according to the manufacturers' instructions by using manual technique, ProTaper rotary system, or One Shape rotary system. Sterilized saline was used as an irrigant, and bacterial extrusion was quantified as colony-forming units/milliliter. The results obtained were statistically analyzed by using one-way analysis of variance for intergroup comparison and post hoc Tukey test for pair-wise comparison. The level for accepting statistical significance was set at P step-back technique exhibiting significantly more bacterial extrusion than the engine-driven systems. Of the 2 engine-driven systems, ProTaper rotary extruded significantly more bacteria than One Shape rotary system (P engine-driven nickel-titanium systems were associated with less apical extrusion. The instrument design may play a role in amount of extrusion. Copyright © 2015 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  11. An overview of the NASA rotary engine research program

    Science.gov (United States)

    Meng, P. R.; Hady, W. F.

    1984-01-01

    A brief overview and technical highlights of the research efforts and studies on rotary engines over the last several years at the NASA Lewis Research Center are presented. The test results obtained from turbocharged rotary engines and preliminary results from a high performance single rotor engine were discussed. Combustion modeling studies of the rotary engine and the use of a Laser Doppler Velocimeter to confirm the studies were examined. An in-house program in which a turbocharged rotary engine was installed in a Cessna Skymaster for ground test studies was reviewed. Details are presented on single rotor stratified charge rotary engine research efforts, both in-house and on contract.

  12. Rotary Stirling-Cycle Engine And Generator

    Science.gov (United States)

    Chandler, Joseph A.

    1990-01-01

    Proposed electric-power generator comprises three motor generators coordinated by microprocessor and driven by rotary Stirling-cycle heat engine. Combination offers thermodynamic efficiency of Stirling cycle, relatively low vibration, and automatic adjustment of operating parameters to suit changing load on generator. Rotary Stirling cycle engine converts heat to power via compression and expansion of working gas between three pairs of rotary pistons on three concentric shafts in phased motion. Three motor/generators each connected to one of concentric shafts, can alternately move and be moved by pistons. Microprocessor coordinates their operation, including switching between motor and generator modes at appropriate times during each cycle.

  13. Rotary endodontics in primary teeth - A review.

    Science.gov (United States)

    George, Sageena; Anandaraj, S; Issac, Jyoti S; John, Sheen A; Harris, Anoop

    2016-01-01

    Endodontic treatment in primary teeth can be challenging and time consuming, especially during canal preparation, which is considered one of the most important steps in root canal therapy. The conventional instrumentation technique for primary teeth remains the "gold-standard" over hand instrumentation, which makes procedures much more time consuming and adversely affects both clinicians and patients. Recently nickel-titanium (Ni-Ti) rotary files have been developed for use in pediatric endodontics. Using rotary instruments for primary tooth pulpectomies is cost effective and results in fills that are consistently uniform and predictable. This article reviews the use of nickel-titanium rotary files as root canal instrumentation in primary teeth. The pulpectomy technique is described here according to different authors and the advantages and disadvantages of using rotary files are discussed.

  14. Rotary reactor for atomic layer deposition on large quantities of nanoparticles

    International Nuclear Information System (INIS)

    McCormick, J. A.; Cloutier, B. L.; Weimer, A. W.; George, S. M.

    2007-01-01

    Challenges are encountered during atomic layer deposition (ALD) on large quantities of nanoparticles. The particles must be agitated or fluidized to perform the ALD surface reactions in reasonable times and to prevent the particles from being agglomerated by the ALD film. The high surface area of nanoparticles also demands efficient reactant usage because large quantities of reactant are required for the surface reactions to reach completion. The residence time of the reactant in a fluidized particle bed reactor may be too short for high efficiency if the ALD surface reactions have low reactive sticking coefficients. To address these challenges, a novel rotary reactor was developed to achieve constant particle agitation during static ALD reactant exposures. In the design of this new reactor, a cylindrical drum with porous metal walls was positioned inside a vacuum chamber. The porous cylindrical drum was rotated by a magnetically coupled rotary feedthrough. By rotating the cylindrical drum to obtain a centrifugal force of less than one gravitational force, the particles were agitated by a continuous 'avalanche' of particles. In addition, an inert N 2 gas pulse helped to dislodge the particles from the porous walls and provided an efficient method to purge reactants and products from the particle bed. The effectiveness of this rotary reactor was demonstrated by Al 2 O 3 ALD on ZrO 2 particles. A number of techniques including transmission electron microscopy, Fourier transform infrared spectroscopy, and x-ray photoelectron spectroscopy confirmed that the Al 2 O 3 ALD film conformally coats the ZrO 2 particles. Combining static reactant exposures with a very high surface area sample in the rotary reactor also provides unique opportunities for studying the surface chemistry during ALD

  15. Fundamental principles of rotary displacement meters

    Energy Technology Data Exchange (ETDEWEB)

    Rosen, J. [Schlumberger Industries, Owenton, KY (United States)

    1995-12-01

    The gas meter exists to continually and accurately measure the volume of gas supplied over the complete flow range of the load. In effect the gas meter serves as the {open_quotes}cash register{close_quotes} of the gas industry; its accurate and dependable performance ensures fair dealings for both the supplier and the user. An investment both in and of itself, the gas meter should be chosen as a function of its usefullness both over the short term and the long term. Thus in addition to initial cost, one must take into account various associated factors, costs and benefits, including the following: Design Characteristics Application, suitability, Meter features and options, Operation constraints, Installation, Service and maintenance, Repair and replacement, Life expectancy, Compatibility with complimentary products, Correcting devices, Remote reading capabilities, Data generation and gathering, Upgradeabilty. This paper will look at one positive displacement meter, the Rotary meter, and address the fundamentals principals of the technology as well as looking at some of the benefits derived from its application. Rotary positive displacement meters were introduced at the end of last century. Used primarily for metering transmission sized loads, the meters` measuring capabilities have extended to cover nearly all areas of distribution with exception of domestic applications. Rotary meters are available in rated capacities from 800 cfh to 102,000 cfh and operating pressures from 175 PSIG to 1440 PSIG. The use of rotary meters on load ranges in the 800 to 10,000 cfh category has increased and is replacing the use of diaphragm meters because of the smaller relative size of rotaries, and improvements in rangeabilities in the last few years. Turbine meters are usually the meter of choice on loads over 16,000 cfh unless a meter with high rangeability is required because of varying load characteristics, in which case a large foot mounted rotary might still be selected.

  16. A rotary drive

    International Nuclear Information System (INIS)

    Causer, R.

    1983-01-01

    A rotary drive for a manipulator or teleoperator comprises a ring member freely rotatable about an eccentric boss extending from an input driver shaft. The ring member has a tapered rim portion wedged between two resiliently biassed friction rings of larger diameter than the ring member and coaxial with the driver shaft, and the ring member is rotatably connected to an output driven shaft. The rotary drive provides a considerable velocity ratio, and also provides a safety feature in that friction between the rim portion and the friction rings only causes rotation of the driven shaft if the load on the driven shaft is less than a certain limiting value. This limiting value may be varied by adjusting the resilient bias on the friction rings. (author)

  17. Rotary drum dryers for coal slurries

    Energy Technology Data Exchange (ETDEWEB)

    Baunack, F

    1983-04-01

    The suitability, sizing and internal equipment of rotary drum dryers for high-ash coal slurries are discussed. Rotary dryers will handle also difficult slurries; by suitable drum sizes, lifter blades and chains not only high specific evaporation capacities can be achieved but also very high throughputs of up to 400 tons/h of finished product and high evaporation capacities of 60 tons/h.

  18. Split Coil Forms for Rotary Transformers

    Science.gov (United States)

    Mclyman, C. W. T.

    1982-01-01

    Split cores for rotor and stator windings of rotary transformer mounted around their respective coils (which are in bobbins) and cemented together. This arrangement simplifies winding of stator coil to go in a slot in inner diameter of stator coil. One practical application of rotary transformers fabricated according to this technique is for centrifuges, in which conventional sliprings are of uncertain reliability.

  19. Fabrication works on rotary kiln fluidized bed

    International Nuclear Information System (INIS)

    Shahazrin Mohd Nasir; Mohamad Azman Che Mat Isa; Mohamad Puad Haji Abu; Mohd Fairus Abdul Farid

    2005-01-01

    Rotary kiln has been widely used in incineration and studied by many researches. Solid wastes of various shapes, sizes and heat value can be fed into rotary kiln either in batches or continually. Waste combustion in rotary kiln involves rotation method and the residence time depends on the length and diameter of the rotary kiln and the total stichomythic air given to the system.Rocking system is another technology used in incinerator. In the rocking system, internal elements in the combustion chamber move to transports and mix the burning waste so that all combustible material in the waste is fully burnt. Another technology in incinerator is the fluidized bed. This method uses air to fluidized the sand thus enhancing the combustion process. The total air is controlled in order to obtain a suitable fluidized condition.This preliminary study was conducted to study the feasibility of an incinerator system when three components viz. the rotary kiln, rocking system and fluidized bed are combined. This research was also conducted to obtain preliminary data parameters of the three components such as the suitable temperature, the angle of the kiln, residence time, total air for fluidization, rocking speed and the devolatilization rate. The samples used in this research were the palm oil kernel shells. (Author)

  20. Rotary drum for centrifuge

    International Nuclear Information System (INIS)

    Sakurai, Mitsuo; Ichinoto, Seiichi.

    1972-01-01

    An outwardly concaved metallic end plate is fitted into each end of a metallic rotary drum for a centrifuge until each end face of the drum is brought to bear upon a section of the end plate radially projected in a direction perpendicular to the axis of rotation of the drum, said section being provided at the marginal edge of the end plate. Following completion of the fitting operation, the end plate is welded to the rotary drum. During high speed rotation, the drum contracts axially and expands radially, while the concave end plate, radially tensioned due to the radial expansion of the drum, undergoes a reduction in its degree of concavity resulting in outwardly directed axial displacement of the end plate proper its marginal edge remaining unaffected relative to the drum. Such displacement conpensates for axial contraction of the drum. Since displacement of the end plate and contraction of the drum depend upon the speed of rotation, substantial axial distortion of the drum can be avoided relative to the end plates at both low and high speeds to permit a high degree of balance for the rotary drum. (Ohno, Y.)

  1. Rotary and radial forcing effects on center-of-mass locomotion dynamics.

    Science.gov (United States)

    Shen, Z H; Larson, P L; Seipel, J E

    2014-09-01

    Rotary and radial forcing are two common actuation methods for legged robots. However, these two orthogonal methods of center-of-mass (CoM) forcing have not been compared as potentially alternative strategies of actuation. In this paper, we compare the CoM stability and energetics of running with rotary and radial actuation through the simulation of two models: the rotary-forced spring-loaded inverted pendulum (rotary-forced-SLIP), and the radially-forced-SLIP. We model both radial and rotary actuation in the simplest way, applying them as a constant force during the stance portion of the gait. A simple application of constant rotary forcing throughout stance is capable of producing fully-asymptotically stable motion; however, a similarly constant application of radial forcing throughout the stance is not capable of producing stable solutions. We then allow both the applied rotary and radial forcing functions to turn on or off based on the occurrence of the mid-stance event, which breaks the symmetry of actuation during stance towards a net forward propulsion. We find that both a rotary force applied in the first half of stance and a radial force applied in the second half of stance, are capable of stabilizing running. Interestingly, these two forcing methods improve the motion stability in different ways. Rotary forcing first reduces then greatly increases the size of the stable parameter region when gradually increased. Radial forcing expands the stable parameter region, but only in a moderate way. Also, it is found that parameter region stabilized by rotary and radial forcing are largely complementary. Overall, rotary forcing can better stabilize running for both constant and event-based forcing functions that were attempted. This indicates that rotary forcing has an inherent capability of stabilizing running, even when minimal time-or-event-or-state feedback is present. Radial forcing, however, tends to be more energy efficient when compared to rotary forcing

  2. Stratified charge rotary engine combustion studies

    Science.gov (United States)

    Shock, H.; Hamady, F.; Somerton, C.; Stuecken, T.; Chouinard, E.; Rachal, T.; Kosterman, J.; Lambeth, M.; Olbrich, C.

    1989-07-01

    Analytical and experimental studies of the combustion process in a stratified charge rotary engine (SCRE) continue to be the subject of active research in recent years. Specifically to meet the demand for more sophisticated products, a detailed understanding of the engine system of interest is warranted. With this in mind the objective of this work is to develop an understanding of the controlling factors that affect the SCRE combustion process so that an efficient power dense rotary engine can be designed. The influence of the induction-exhaust systems and the rotor geometry are believed to have a significant effect on combustion chamber flow characteristics. In this report, emphasis is centered on Laser Doppler Velocimetry (LDV) measurements and on qualitative flow visualizations in the combustion chamber of the motored rotary engine assembly. This will provide a basic understanding of the flow process in the RCE and serve as a data base for verification of numerical simulations. Understanding fuel injection provisions is also important to the successful operation of the stratified charge rotary engine. Toward this end, flow visualizations depicting the development of high speed, high pressure fuel jets are described. Friction is an important consideration in an engine from the standpoint of lost work, durability and reliability. MSU Engine Research Laboratory efforts in accessing the frictional losses associated with the rotary engine are described. This includes work which describes losses in bearing, seal and auxillary components. Finally, a computer controlled mapping system under development is described. This system can be used to map shapes such as combustion chamber, intake manifolds or turbine blades accurately.

  3. Ka-band waveguide rotary joint

    KAUST Repository

    Yevdokymov, Anatoliy

    2013-04-11

    The authors present a design of a waveguide rotary joint operating in Ka-band with central frequency of 33 GHz, which also acts as an antenna mount. The main unit consists of two flanges with a clearance between them; one of the flanges has three circular choke grooves. Utilisation of three choke grooves allows larger operating clearance. Two prototypes of the rotary joint have been manufactured and experimentally studied. The observed loss is from 0.4 to 0.8 dB in 1.5 GHz band.

  4. Rotary endodontics in primary teeth – A review

    Science.gov (United States)

    George, Sageena; Anandaraj, S.; Issac, Jyoti S.; John, Sheen A.; Harris, Anoop

    2015-01-01

    Endodontic treatment in primary teeth can be challenging and time consuming, especially during canal preparation, which is considered one of the most important steps in root canal therapy. The conventional instrumentation technique for primary teeth remains the “gold-standard” over hand instrumentation, which makes procedures much more time consuming and adversely affects both clinicians and patients. Recently nickel–titanium (Ni–Ti) rotary files have been developed for use in pediatric endodontics. Using rotary instruments for primary tooth pulpectomies is cost effective and results in fills that are consistently uniform and predictable. This article reviews the use of nickel–titanium rotary files as root canal instrumentation in primary teeth. The pulpectomy technique is described here according to different authors and the advantages and disadvantages of using rotary files are discussed. PMID:26792964

  5. Rotary endodontics in primary teeth – A review

    Directory of Open Access Journals (Sweden)

    Sageena George

    2016-01-01

    Full Text Available Endodontic treatment in primary teeth can be challenging and time consuming, especially during canal preparation, which is considered one of the most important steps in root canal therapy. The conventional instrumentation technique for primary teeth remains the “gold-standard” over hand instrumentation, which makes procedures much more time consuming and adversely affects both clinicians and patients. Recently nickel–titanium (Ni–Ti rotary files have been developed for use in pediatric endodontics. Using rotary instruments for primary tooth pulpectomies is cost effective and results in fills that are consistently uniform and predictable. This article reviews the use of nickel–titanium rotary files as root canal instrumentation in primary teeth. The pulpectomy technique is described here according to different authors and the advantages and disadvantages of using rotary files are discussed.

  6. Rotary capacitor

    CERN Multimedia

    CERN PhotoLab

    1971-01-01

    The rotating wheel of the rotary capacitor representing the most critical part of the new radio-frequency system of the synchro-cyclotron. The three rows of teeth on the circumference of the wheel pass between four rows of stator blades with a minimum clearance of 1 mm at a velocity of 1700 rev/min.

  7. Simulation and Optimization of Contactless Power Transfer System for Rotary Ultrasonic Machining

    Directory of Open Access Journals (Sweden)

    Wang Xinwei

    2016-01-01

    Full Text Available In today’s rotary ultrasonic machining (RUM, the power transfer system is based on a contactless power system (rotary transformer rather than the slip ring that cannot cope with high-speed rotary of the tool. The efficiency of the rotary transformer is vital to the whole rotary ultrasonic machine. This paper focused on simulation of the rotary transformer and enhancing the efficiency of the rotary transformer by optimizing three main factors that influence its efficiency, including the gap between the two ferrite cores, the ratio of length and width of the ferrite core and the thickness of ferrite. The finite element model of rotary transformer was built on Maxwell platform. Simulation and optimization work was based on the finite element model. The optimization results compared with the initial simulation result showed an approximate 18% enhancement in terms of efficiency, from 77.69% to 95.2%.

  8. Rotary and radial forcing effects on center-of-mass locomotion dynamics

    International Nuclear Information System (INIS)

    Shen, Z H; Larson, P L; Seipel, J E

    2014-01-01

    Rotary and radial forcing are two common actuation methods for legged robots. However, these two orthogonal methods of center-of-mass (CoM) forcing have not been compared as potentially alternative strategies of actuation. In this paper, we compare the CoM stability and energetics of running with rotary and radial actuation through the simulation of two models: the rotary-forced spring-loaded inverted pendulum (rotary-forced-SLIP), and the radially-forced-SLIP. We model both radial and rotary actuation in the simplest way, applying them as a constant force during the stance portion of the gait. A simple application of constant rotary forcing throughout stance is capable of producing fully-asymptotically stable motion; however, a similarly constant application of radial forcing throughout the stance is not capable of producing stable solutions. We then allow both the applied rotary and radial forcing functions to turn on or off based on the occurrence of the mid-stance event, which breaks the symmetry of actuation during stance towards a net forward propulsion. We find that both a rotary force applied in the first half of stance and a radial force applied in the second half of stance, are capable of stabilizing running. Interestingly, these two forcing methods improve the motion stability in different ways. Rotary forcing first reduces then greatly increases the size of the stable parameter region when gradually increased. Radial forcing expands the stable parameter region, but only in a moderate way. Also, it is found that parameter region stabilized by rotary and radial forcing are largely complementary. Overall, rotary forcing can better stabilize running for both constant and event-based forcing functions that were attempted. This indicates that rotary forcing has an inherent capability of stabilizing running, even when minimal time-or-event-or-state feedback is present. Radial forcing, however, tends to be more energy efficient when compared to rotary forcing

  9. Deformation analysis of rotary combustion engine housings

    Science.gov (United States)

    Vilmann, Carl

    1991-01-01

    This analysis of the deformation of rotary combustion engine housings targeted the following objectives: (1) the development and verification of a finite element model of the trochoid housing, (2) the prediction of the stress and deformation fields present within the trochoid housing during operating conditions, and (3) the development of a specialized preprocessor which would shorten the time necessary for mesh generation of a trochoid housing's FEM model from roughly one month to approximately two man hours. Executable finite element models were developed for both the Mazda and the Outboard Marine Corporation trochoid housings. It was also demonstrated that a preprocessor which would hasten the generation of finite element models of a rotary engine was possible to develop. The above objectives are treated in detail in the attached appendices. The first deals with finite element modeling of a Wankel engine center housing, and the second with the development of a preprocessor that generates finite element models of rotary combustion engine center housings. A computer program, designed to generate finite element models of user defined rotary combustion engine center housing geometries, is also included.

  10. Rotary-Atomizer Electric Power Generator

    Science.gov (United States)

    Nguyen, Trieu; Tran, Tuan; de Boer, Hans; van den Berg, Albert; Eijkel, Jan C. T.

    2015-03-01

    We report experimental and theoretical results on a ballistic energy-conversion method based on a rotary atomizer working with a droplet acceleration-deceleration cycle. In a rotary atomizer, liquid is fed onto the center of a rotating flat surface, where it spreads out under the action of the centrifugal force and creates "atomized" droplets at its edge. The advantage of using a rotary atomizer is that the centrifugal force exerted on the fluid on a smooth, large surface is not only a robust form of acceleration, as it avoids clogging, but also easily allows high throughput, and produces high electrical power. We successfully demonstrate an output power of 4.9 mW and a high voltage up to 3120 V. At present, the efficiency of the system is still low (0.14%). However, the conversion mechanism of the system is fully interpreted in this paper, permitting a conceptual understanding of system operation and providing a roadmap for system optimization. This observation will open up a road for building power-generation systems in the near future.

  11. Rotary jagas stipendiume

    Index Scriptorium Estoniae

    2009-01-01

    Pärnu Rotary klubi aastapäevapeol 11. mail Ammende villas anti stipendium viiele Pärnumaa noorele, teiste seas pälvis preemia Pärnu Ülejõe Gümnaasiumi muusikaõpetaja Fred Rõigas ja Pärnu Muusikakoolis trompetit õppiv Chris Sommer

  12. Note: A novel rotary actuator driven by only one piezoelectric actuator.

    Science.gov (United States)

    Huang, Hu; Fu, Lu; Zhao, Hongwei; Shi, Chengli; Ren, Luquan; Li, Jianping; Qu, Han

    2013-09-01

    This paper presents a novel piezo-driven rotary actuator based on the parasitic motion principle. Output performances of the rotary actuator were tested and discussed. Experiment results indicate that using only one piezoelectric actuator and simple sawtooth wave control, the rotary actuator reaches the rotation velocity of about 20,097 μrad/s when the driving voltage is 100 V and the driving frequency is 90 Hz. The actuator can rotate stably with the minimum resolution of 0.7 μrad. This paper verifies feasibility of the parasitic motion principle for applications of rotary actuators, providing new design ideas for precision piezoelectric rotary actuators.

  13. Development of the RANCOR Rotary-Percussive Coring System for Mars Sample Return

    Science.gov (United States)

    Paulsen, Gale; Indyk, Stephen; Zacny, Kris

    2014-01-01

    A RANCOR drill was designed to fit a Mars Exploration Rover (MER) class vehicle. The low mass of 3 kg was achieved by using the same actuator for three functions: rotation, percussions, and core break-off. Initial testing of the drill exposed an unexpected behavior of an off-the-shelf sprag clutch used to couple and decouple rotary-percussive function from the core break off function. Failure of the sprag was due to the vibration induced during percussive drilling. The sprag clutch would back drive in conditions where it was expected to hold position. Although this did not affect the performance of the drill, it nevertheless reduced the quality of the cores produced. Ultimately, the sprag clutch was replaced with a custom ratchet system that allowed for some angular displacement without advancing in either direction. Replacing the sprag with the ratchet improved the collected core quality. Also, premature failure of a 300-series stainless steel percussion spring was observed. The 300-series percussion spring was ultimately replaced with a music wire spring based on performances of previously designed rotary-percussive drill systems.

  14. Wireless Power Transfer System for Rotary Parts Telemetry of Gas Turbine Engine

    Directory of Open Access Journals (Sweden)

    Xiaoming He

    2018-04-01

    Full Text Available A novel wireless power transfer approach for the rotary parts telemetry of a gas turbine engine is proposed. The advantages of a wireless power transfer (WPT system in the power supply for the rotary parts telemetry of a gas turbine engine are introduced. By simplifying the circuit of the inductively-coupled WPT system and developing its equivalent circuit model, the mathematical expressions of transfer efficiency and transfer power of the system are derived. A mutual inductance model between receiving and transmitting coils of the WPT system is presented and studied. According to this model, the mutual inductance between the receiving and the transmitting coils can be calculated at different axial distances. Then, the transfer efficiency and transfer power can be calculated as well. Based on the test data, the relationship of the different distances between the two coils, the transfer efficiency, and transfer power is derived. The proper positions where the receiving and transmitting coils are installed in a gas turbine engine are determined under conditions of satisfying the transfer efficiency and transfer power that the telemetry system required.

  15. Rotary compression process for producing toothed hollow shafts

    Directory of Open Access Journals (Sweden)

    J. Tomczak

    2014-10-01

    Full Text Available The paper presents the results of numerical analyses of the rotary compression process for hollow stepped shafts with herringbone teeth. The numerical simulations were performed by Finite Element Method (FEM, using commercial software package DEFORM-3D. The results of numerical modelling aimed at determining the effect of billet wall thickness on product shape and the rotary compression process are presented. The distributions of strains, temperatures, damage criterion and force parameters of the process determined in the simulations are given, too. The numerical results obtained confirm the possibility of producing hollow toothed shafts from tube billet by rotary compression methods.

  16. Control and data acquisition system for rotary compressor

    Directory of Open Access Journals (Sweden)

    Buczaj Marcin

    2017-01-01

    Full Text Available The rotary compressor (crimping machine is a machine designed for making hollow forgings. The rotary compressor is a prototype device designed and built at the Technical University of Lublin. The compressor is dedicated to perform laboratory tests related to the hollow forgings of various shapes using different materials. Since the rotary compressor is an experimental device, there is no control and acquisition data system available. The article presents the concept and the capabilities of the computer control and data acquisition system supporting rotary compressing process. The main task of software system is acquisition of force and kinetic parameters related to the analysed process of the rotary forging compression. The software allows the user to declare the course of the forming forgings. This system allows current recording and analysis of four physical values: feed rate (speed of working head movement, hydraulic oil pressure at inlet and outlet of hydraulic cylinder and the torque of engine. Application functions can be divided into three groups: the configuration of the pressing process, the acquisition and analysis of data from the pressing process and the recording and presentation of stored results. The article contains a detailed description about hardware and software implementation of mentioned functions.

  17. Rotary plug seal

    International Nuclear Information System (INIS)

    Ito, Koji; Abiko, Yoshihiro.

    1981-01-01

    Purpose: To enable fuel exchange even upon failure of regular seals and also to enable safety seal exchange by the detection of the reduction in the contact pressure of a rotary plug seal. Constitution: If one of a pair of regular tube seals for the rotary plug is failed during ordinary operation of a FBR type reactor, the reduction in the contact pressure of the seal to the plug gibbousness is detected by a pressure gauge and a solenoid valve is thereby closed. Thus, a back-up-tube seal provided above or below the tube seal is press-contacted by way of argon gas to the gibbousness to enter into operation state and lubricants are supplied from an oil tank. In such a structure, the back-up-tube seal is operated before the failure of the tube seal to enable to continue the fuel exchange work, as well as safety exchange for the tube seal. (Moriyama, K.)

  18. The Wankel rotary engine a history

    CERN Document Server

    Hege, John B

    2007-01-01

    "It stands apart from the crowd as the only history of the Wankel rotary engine that brings the story into the 21st Century"--SAH Journal; "this book continues to excel...terrific...technophiles will love this"--Hemmings Motor News; "excellent"--Hemmings Sports & Exotic Car; "a complete history...guaranteed to delight"--Old Cars Weekly; "definitive…a must-read"--Choice; "informative"--SciTech Book News; "goes a long way to explaining everything"--The Automobile. This complete and well-illustrated account traces the full history of the Wankel rotary engine and its use in various cars, motorcycles, snowmobiles and other applications. It clearly explains the working of the engine and the technical challenges it presented--the difficulty of designing effective and durable seals, early emissions troubles, high fuel consumption, and others. The work done by several companies to overcome these problems is described in detail, as are the economic and political troubles that nearly killed the rotary in the 19...

  19. Adiabatic Wankel type rotary engine

    Science.gov (United States)

    Kamo, R.; Badgley, P.; Doup, D.

    1988-01-01

    This SBIR Phase program accomplished the objective of advancing the technology of the Wankel type rotary engine for aircraft applications through the use of adiabatic engine technology. Based on the results of this program, technology is in place to provide a rotor and side and intermediate housings with thermal barrier coatings. A detailed cycle analysis of the NASA 1007R Direct Injection Stratified Charge (DISC) rotary engine was performed which concluded that applying thermal barrier coatings to the rotor should be successful and that it was unlikely that the rotor housing could be successfully run with thermal barrier coatings as the thermal stresses were extensive.

  20. Rotary Percussive Auto-Gopher for Deep Drilling and Sampling

    Science.gov (United States)

    Bar-Cohen, Yoseph; Badescu, Mircea; Sherrit, Stewart

    2009-01-01

    The term "rotary percussive auto-gopher" denotes a proposed addition to a family of apparatuses, based on ultrasonic/ sonic drill corers (USDCs), that have been described in numerous previous NASA Tech Briefs articles. These apparatuses have been designed, variously, for boring into, and/or acquiring samples of, rock or other hard, brittle materials of geological interest. In the case of the rotary percussive autogopher, the emphasis would be on developing an apparatus capable of penetrating to, and acquiring samples at, depths that could otherwise be reached only by use of much longer, heavier, conventional drilling-and-sampling apparatuses. To recapitulate from the prior articles about USDCs: A USDC can be characterized as a lightweight, low-power jackhammer in which a piezoelectrically driven actuator generates ultrasonic vibrations and is coupled to a tool bit through a free mass. The bouncing of the free mass between the actuator horn and the drill bit converts the actuator ultrasonic vibrations into sonic hammering of the drill bit. The combination of ultrasonic and sonic vibrations gives rise to a hammering action (and a resulting chiseling action at the tip of the tool bit) that is more effective for drilling than is the microhammering action of ultrasonic vibrations alone. The hammering and chiseling actions are so effective that the size of the axial force needed to make the tool bit advance into soil, rock, or another material of interest is much smaller than in ordinary rotary drilling, ordinary hammering, or ordinary steady pushing. The predecessor of the rotary percussive auto-gopher is an apparatus, now denoted an ultrasonic/sonic gopher and previously denoted an ultrasonic gopher, described in "Ultrasonic/ Sonic Mechanism for Drilling and Coring" (NPO-30291), NASA Tech Briefs Vol. 27, No. 9 (September 2003), page 65. The ultrasonic/sonic gopher is intended for use mainly in acquiring cores. The name of the apparatus reflects the fact that, like a

  1. Equations For Rotary Transformers

    Science.gov (United States)

    Salomon, Phil M.; Wiktor, Peter J.; Marchetto, Carl A.

    1988-01-01

    Equations derived for input impedance, input power, and ratio of secondary current to primary current of rotary transformer. Used for quick analysis of transformer designs. Circuit model commonly used in textbooks on theory of ac circuits.

  2. Research on dynamic balancing simulation of rotary shaft based on ADAMS

    Science.gov (United States)

    Zheng, Weiqiang; Rui, Chengjie; Yang, Jie; Liu, Pingyi

    2018-02-01

    Due to the design and processing technology of rotary shaft, the mass center of it does not coincide with the rotating axis of the rotary shaft and there is an unbalanced mass. The unbalanced mass can have some disadvantages, such as the centrifugal force, the vibration and so on. Those disadvantages could reduce the accuracy and service life of the equipment.In this paper, the dynamic balance of the rotary shaft is analysed by the theory analysis combined with the dynamic simulation software. This method ensures that the rotary shaft meets the dynamic balancing requirements during the design stage. It effectively supports the structural design of the rotary shift, and provides a way of thinking and method for the design and development of the same type of products.

  3. Encapsulated Ball Bearings for Rotary Micro Machines

    Science.gov (United States)

    2007-01-01

    occurrence as well as the overall tribological properties of the bearing mechanism. Firstly, the number of stainless steel balls influences not only the load...stacks.iop.org/JMM/17/S224 Abstract We report on the first encapsulated rotary ball bearing mechanism using silicon microfabrication and stainless steel balls...The method of capturing stainless steel balls within a silicon race to support a silicon rotor both axially and radially is developed for rotary micro

  4. Linear rotary optical delay lines

    Science.gov (United States)

    Guerboukha, Hichem; Qu, Hang; Skorobogatiy, Maksim

    2016-03-01

    We present a semi-analytical solution for the design of a high-speed rotary optical delay line that use a combination of two rotating curvilinear reflectors. We demonstrate that it is possible to design an infinite variety of the optical delay lines featuring linear dependence of the optical delay on the rotation angle. This is achieved via shape optimization of the rotating reflector surfaces. Moreover, a convenient spatial separation of the incoming and outgoing beams is possible. For the sake of example, we present blades that fit into a circle of 10cm diameter. Finally, a prototype of a rotary delay line is fabricated using CNC machining, and its optical properties are characterized.

  5. Rotary pneumatic valve

    Science.gov (United States)

    Hardee, Harry C.

    1991-01-01

    A rotary pneumatic valve which is thrust balanced and the pneumatic pressure developed produces only radial loads on the valve cylinder producing negligible resistance and thus minimal torque on the bearings of the valve. The valve is multiplexed such that at least two complete switching cycles occur for each revolution of the cylinder spindle.

  6. A Review of Heavy-Fueled Rotary Engine Combustion Technologies

    Science.gov (United States)

    2011-05-01

    Triangle Park, NC, 2009. 17. Shimizu, R.; Tadokoro, T.; Nakanishi, T.; Funamoto, J. Mazda 4-Rotor Rotary Engine for the Le Mans 24-Hour Endurance...2000. 102. Schock, H.; Hamady, F.; Somerton , C. Stratified Charge Rotary Engine Combustion Studies; NASA-CR-197985; National Aeronautics and

  7. A bistable electromagnetically actuated rotary gate microvalve

    International Nuclear Information System (INIS)

    Luharuka, Rajesh; Hesketh, Peter J

    2008-01-01

    Two types of rotary gate microvalves are developed for flow modulation in microfluidic systems. These microvalves have been tested for an open flow rate of up to 100 sccm and operate under a differential pressure of 6 psig with flow modulation of up to 100. The microvalve consists of a suspended gate that rotates in the plane of the chip to regulate flow through the orifice. The gate is suspended by a novel fully compliant in-plane rotary bistable micromechanism (IPRBM) that advantageously constrains the gate in all degrees of freedom except for in-plane rotational motion. Multiple inlet/outlet orifices provide flexibility of operating the microvalve in three different flow configurations. The rotary gate microvalve is switched with an external electromagnetic actuator. The suspended gate is made of a soft magnetic material and its electromagnetic actuation is based on the operating principle of a variable-reluctance stepper motor

  8. Streaming current of a rotary atomizer for energy harvesting

    NARCIS (Netherlands)

    Nguyen, Trieu; de Boer, Hans L.; Tran, T.; van den Berg, Albert; Eijkel, Jan C.T.; Zengerle, R.

    2013-01-01

    We present the experimental results of an energy conversion system based on a rotary atomizer and the streaming current phenomenon. The advantage of using a rotary atomizer instead of a channel or membrane micropore as in conventional pressure-driven approached is that the centrifugal force exerted

  9. Analysis of Apex Seal Friction Power Loss in Rotary Engines

    Science.gov (United States)

    Handschuh, Robert F.; Owen, A. Karl

    2010-01-01

    An analysis of the frictional losses from the apex seals in a rotary engine was developed. The modeling was initiated with a kinematic analysis of the rotary engine. Next a modern internal combustion engine analysis code was altered for use in a rotary engine to allow the calculation of the internal combustion pressure as a function of rotor rotation. Finally the forces from the spring, inertial, and combustion pressure on the seal were combined to provide the frictional horsepower assessment.

  10. Assessment of a lubricant based nanofluid application in a rotary system

    International Nuclear Information System (INIS)

    Hajmohammadi, M.R.

    2017-01-01

    Highlights: • Application of metallic nanoparticles in a rotary system is evaluated. • Evaluations are based on first and second laws of thermodynamics. • Two-phase numerical method is used and lubricant is considered inhomogeneous. • Nanoparticles with limited concentricity in lowspeed rotary system are recommended. - Abstract: Rotary systems and nanofluids are frequently used in energy conversion and management systems. In this paper, a numerical study is performed to evaluate the application of metallic nano-particles in a rotary system filled with a lubricant from first and second laws of thermodynamics points of view. The nano-lubricant (lubricant based nanofluid) is considered inhomogeneous with dependent transport properties on nano-particles volume fraction, nano-particles size and the temperature. A two-phase model is undertaken to account for the Brownian motion and thermophoresis diffusion. The principal objective centers in the advantages and penalties of using nano-lubricant over the pure lubricant on the basis of first and second law (of thermodynamics). The numerical results demonstrate that the nano-particles enhance the thermal performance of the rotary system. However, undesirable aspect from hydro-dynamical and second law (of thermodynamic) perspectives are reported. While a nano-lubricant with limited volume fraction in low speed rotary system is recommended, the disadvantages of nano-lubricants with high volume fractions and/or used in a high-speed rotary system are dominant to nano-lubricants advantages and must be avoided.

  11. Design of angular position detector for rotary stepping motor of CEDM

    International Nuclear Information System (INIS)

    Park, Seok Ha; Kim, Jong In; Kim, Ji Ho; Huh, Hyung; Yu, Je Yong

    2000-11-01

    The position of control rod must be detected continuously to control CEDM control rod used in SMART. The up-and-down movement of control rod can be detected approximately by using a position indicator, but an additionary sensor should be required because the accuracy of it is low. And because the rotary stepping motor for SMART CEDM is to work at harsh conditions of high temperature, pressure and radiation, it is difficult to select an adequate sensor from commercially available products. Therefore, a sensor to monitor the position of control rod by detecting the position of rotary angle for stepping motor should studied. This paper analyzes and compares the techniques of Synchro, Resolver, and Magnesyn being used as a rotary angle detector for stepping motor. The rotary angle detector by using our unique concept is designed on the basis of upper work. The prototype of rotary angle detector is produced and the results of test and valuation is presented

  12. Rotary bayonets for cryogenic and vacuum service

    International Nuclear Information System (INIS)

    Rucinski, R.A.; Dixon, K.D.; Krasa, R.; Krempetz, K.J.; Mulholland, G.T.; Trotter, G.R.; Urbin, J.B.

    1993-07-01

    Rotary bayonets were designed, tested, and installed for liquid nitrogen, liquid argon, and vacuum service. This paper will present the design, testing, and service record for two sizes of vacuum jacketed cryogenic rotary bayonets and two sizes of vacuum service rotary bayonets. Materials used in construction provide electrical isolation across the bayonet joint. The joint permits 360 degrees of rotation between the male and female pipe sections while maintaining integrity of service. Assemblies using three such joints were built to allow end connection points to be translated through at least 1 meter of horizontal travel while kept in service. Vacuum jacketed sizes built in-house at Fermi National Accelerator Laboratory are 1-1/2 in. inner pipe size, 3 in. vacuum jacket, and 4 in. inner pipe size, 6 in. vacuum jacket The single wall vacuum service bayonets are in 4 in. and 6 in. pipe sizes. The bayonets have successfully been in active service for over one year

  13. Rotary bayonets for cryogenic and vacuum service

    International Nuclear Information System (INIS)

    Rucinski, R.A.; Dixon, K.D.; Krasa, R.; Krempetz, K.J.; Mulholland, G.T.; Trotter, G.R.; Urbin, J.B.

    1994-01-01

    Rotary bayonets were designed, tested, and installed for liquid nitrogen, liquid argon, and vacuum service. This paper will present the design, testing, and service record for two sizes of vacuum jacketed cryogenic rotary bayonets and two sizes of vacuum service rotary bayonets. Materials used in construction provide electrical isolation across the bayonet joint. The joint permits 360 degrees of rotation between the male and female pipe sections while maintaining integrity of service. Assemblies using three such joints were built to allow end connection points to be translated through at least 1 meter of horizontal travel while kept in service. Vacuum jacketed sizes built in-house at Fermi National Accelerator Laboratory are 1 1/2 inches inner pipe size, 3 inches vacuum jacket, and 4 inches inner pipe size, 6 inches vacuum jacket. The single wall vacuum service bayonets are in 4 inch and 6 inch pipe sizes. The bayonets have successfully been in active service for over one year

  14. Corticotomy-facilitated orthodontics using piezosurgery versus rotary instruments: an experimental study.

    Science.gov (United States)

    Farid, Karim A; Mostafa, Yehya A; Kaddah, Mohammed A; El-Sharaby, Fouad Aly

    2014-10-01

    The aim of this study was to evaluate corticotomy-facilitated orthodontics (CFO) using piezosurgery versus conventional rotary instruments. Ten healthy adult male mongrel dogs of comparable age with a complete set of permanent dentition with average weights between 13-17 kilograms were used. CFO using conventional rotary instruments versus piezosurgery was performed on each dog in a split mouth design. For every dog, mandibular 2nd premolar retraction on each side was attempted after extracting 3rd premolars followed by corticotomy-facilitated orthodontics using conventional rotary surgical burs on the left side and an ultrasonic piezosurgery system on the right side of the same animal. Intraoral measurements of the rate of tooth movement were taken with a sliding caliper. Measurements were performed by the same operator at the time of surgery (appliance delivery) and every month for six months. The dogs were sacrificed after six months from initiation of tooth movement to evaluate the amount of tooth movement for both conventional rotary and piezosurgery corticotomy techniques. A statistically significantly higher mean amount of tooth movement for conventional rotary instrument versus the piezosurgery corticotomy technique was observed at all time intervals. Tooth movement was 1.6 times faster when CFO was done using conventional rotary instruments as compared to a piezosurgery device.

  15. EVALUATION OF ALTERNATIVE FILTER MEDIA FOR THE ROTARY MICROFILTER

    Energy Technology Data Exchange (ETDEWEB)

    Poirier, M.; Herman, D.; Bhave, R.

    2011-09-13

    SRS is currently developing and testing several processes to treat high level radioactive liquid waste. These processes include the Integrated Salt Disposition Process (ISDP), the Salt Waste Processing Facility (SWPF), and the Small Column Ion Exchange Process (SCIX). Each of these processes has a solid-liquid separation process that limits its throughput. SRNL researchers identified and tested the rotary microfilter as a technology to increase solid-liquid separation throughput. The testing showed significant improvement in filter flux with the rotary microfilter over the baseline crossflow filter (i.e., 2.5-6.5X during scoping tests, as much as 10X in actual waste tests, and approximately 3X in pilot-scale tests). SRNL received funding from DOE EM-21, and subsequently DOE EM-31 to develop the rotary microfilter for high level radioactive service. The work has included upgrading the rotary microfilter for radioactive service, testing with simulated SRS waste streams, and testing it with simulated Hanford waste streams. While the filtration rate is better than that obtained during testing of crossflow filters, the authors believe the rotary microfilter throughput can be improved by using a better filter membrane. The rotary microfilter membrane is made of stainless steel (Pall PMM050). Previous testing, funded by DOE EM-21, showed that asymmetric filters composed of a ceramic membrane on top of a stainless steel support produced higher filter flux than 100% stainless steel symmetric filters in crossflow filter tests. In that testing, the Pall Accusep and Graver filters produced 13-21% larger filter flux than the baseline 0.1 {micro}m Mott filter. While the improvement in flux is not as dramatic as the improvement of the rotary filter over a crossflow filter, a 13-21% increase could reduce the lifetime of a 30 year process by 4-6 years, with significant cost savings. Subsequent rotary filter testing showed the Pall PMM050 stainless steel filter membrane produced

  16. In vitro assessment of cutting efficiency and durability of zirconia removal diamond rotary instruments.

    Science.gov (United States)

    Kim, Joon-Soo; Bae, Ji-Hyeon; Yun, Mi-Jung; Huh, Jung-Bo

    2017-06-01

    Recently, zirconia removal diamond rotary instruments have become commercially available for efficient cutting of zirconia. However, research of cutting efficiency and the cutting characteristics of zirconia removal diamond rotary instruments is limited. The purpose of this in vitro study was to assess and compare the cutting efficiency, durability, and diamond rotary instrument wear pattern of zirconia diamond removal rotary instruments with those of conventional diamond rotary instruments. In addition, the surface characteristics of the cut zirconia were assessed. Block specimens of 3 mol% yttrium cation-doped tetragonal zirconia polycrystal were machined 10 times for 1 minute each using a high-speed handpiece with 6 types of diamond rotary instrument from 2 manufacturers at a constant force of 2 N (n=5). An electronic scale was used to measure the lost weight after each cut in order to evaluate the cutting efficiency. Field emission scanning electron microscopy was used to evaluate diamond rotary instrument wear patterns and machined zirconia block surface characteristics. Data were statistically analyzed using the Kruskal-Wallis test, followed by the Mann-Whitney U test (α=.05). Zirconia removal fine grit diamond rotary instruments showed cutting efficiency that was reduced compared with conventional fine grit diamond rotary instruments. Diamond grit fracture was the most dominant diamond rotary instrument wear pattern in all groups. All machined zirconia surfaces were primarily subjected to plastic deformation, which is evidence of ductile cutting. Zirconia blocks machined with zirconia removal fine grit diamond rotary instruments showed the least incidence of surface flaws. Although zirconia removal diamond rotary instruments did not show improved cutting efficiency compared with conventional diamond rotary instruments, the machined zirconia surface showed smoother furrows of plastic deformation and fewer surface flaws. Copyright © 2016 Editorial Council

  17. Rotary spin echoes

    Energy Technology Data Exchange (ETDEWEB)

    Solomon, I. [Commissariat a l' energie atomique et aux energies alternatives - CEA, Centre d' Etudes Nucleaires de Saclay, BP2, Gif-sur-Yvette (France)

    1959-07-01

    Torrey has observed the free precession of nuclear spins around an r-f field H{sub 1}, fixed in a frame rotating at the Larmor frequency ω{sub 0} = γH{sub 0} around a large d-c magnetic field H{sub 0}. He showed that for an H{sub 1}, much larger than inhomogeneity of H{sub 0}, the latter has a negligible effect on the decay of the spin magnetization which is mainly due to the inhomogeneity of H{sub 1}. We report here on a method of overcoming the inhomogeneity of H{sub 1}, by production of echoes in the rotating frame ('rotary echoes'). These echoes are obtained by a 180 deg. phase shift at t = τ on the r-f field so that H{sub 1}, is suddenly reversed, producing a re-focussing of the magnetization vectors at the time t = 2 τ. The rotary echoes so obtained are very similar to the usual spin-echoes with, however some specific features that make them particularly suitable for the measurement of long relaxation times. Reprint of a paper published in Physical Review Letters, vol. 2, no. 7, Apr 1959, p. 301-302.

  18. Rotary spin echoes

    International Nuclear Information System (INIS)

    Solomon, I.

    1959-01-01

    Torrey has observed the free precession of nuclear spins around an r-f field H 1 , fixed in a frame rotating at the Larmor frequency ω 0 = γH 0 around a large d-c magnetic field H 0 . He showed that for an H 1 , much larger than inhomogeneity of H 0 , the latter has a negligible effect on the decay of the spin magnetization which is mainly due to the inhomogeneity of H 1 . We report here on a method of overcoming the inhomogeneity of H 1 , by production of echoes in the rotating frame ('rotary echoes'). These echoes are obtained by a 180 deg. phase shift at t = τ on the r-f field so that H 1 , is suddenly reversed, producing a re-focussing of the magnetization vectors at the time t = 2 τ. The rotary echoes so obtained are very similar to the usual spin-echoes with, however some specific features that make them particularly suitable for the measurement of long relaxation times. Reprint of a paper published in Physical Review Letters, vol. 2, no. 7, Apr 1959, p. 301-302

  19. Controlled-air and rotary-kiln proof-of-principle tests

    International Nuclear Information System (INIS)

    Hedahl, T.G.

    1982-05-01

    Although the incinerator tests did not represent optimized processing, general system design characteristics were established. The test results indicated that the rotary kiln incinerator would be most applicable in the Transuranic Waste Treatment Facility (TWTF) for the following reasons: (1) The rotary kiln is more capable of achieving near-complete combustion of the combustibles in the waste mixed with a high proportion of metal and noncombustible waste. Complete combustion of the combustible waste is preferred in order to reduce waste volume and ensure the production of a stable, immobilized waste form. (2) The rotary kiln processing appears to be more flexible. Kiln rotation rate, kiln incline, and waste feed rate and method are system variables which can be altered to meet the needs of processing variable waste compositions. The advantages of the rotary kiln system allow for a practical concept for processing a majority of the radioactive waste at the INEL. However, further engineering tests must be performed to determine the necessary processing angles and design information for TWTF waste processing

  20. Convective heat transfer analysis in aggregates rotary drum reactor

    International Nuclear Information System (INIS)

    Le Guen, Laurédan; Huchet, Florian; Dumoulin, Jean; Baudru, Yvan; Tamagny, Philippe

    2013-01-01

    Heat transport characterisation inside rotary drum dryer has a considerable importance linked to many industrial applications. The present paper deals with the heat transfer analysis from experimental apparatus installed in a large-scale rotary drum reactor applied to the asphalt materials production. The equipment including in-situ thermal probes and external visualization by mean of infrared thermography gives rise to the longitudinal evaluation of inner and external temperatures. The assessment of the heat transfer coefficients by an inverse methodology is resolved in order to accomplish a fin analysis of the convective mechanism inside baffled (or flights) rotary drum. The results are discussed and compared with major results of the literature. -- Highlights: ► A thermal and flow experimentation is performed on a large-scale rotary drum. ► Four working points is chosen in the frame of asphalt materials production. ► Evaluation of the convective transfer mechanisms is calculated by inverse method. ► The drying stage is performed in the combustion area. ► Wall/aggregates heat exchanges have a major contribution in the heating stage

  1. The NMR solution structure of Mycobacterium tuberculosis F-ATP synthase subunit ε provides new insight into energy coupling inside the rotary engine.

    Science.gov (United States)

    Joon, Shin; Ragunathan, Priya; Sundararaman, Lavanya; Nartey, Wilson; Kundu, Subhashri; Manimekalai, Malathy S S; Bogdanović, Nebojša; Dick, Thomas; Grüber, Gerhard

    2018-03-01

    Mycobacterium tuberculosis (Mt) F 1 F 0 ATP synthase (α 3 :β 3 :γ:δ:ε:a:b:b':c 9 ) is essential for the viability of growing and nongrowing persister cells of the pathogen. Here, we present the first NMR solution structure of Mtε, revealing an N-terminal β-barrel domain (NTD) and a C-terminal domain (CTD) composed of a helix-loop-helix with helix 1 and -2 being shorter compared to their counterparts in other bacteria. The C-terminal amino acids are oriented toward the NTD, forming a domain-domain interface between the NTD and CTD. The Mtε structure provides a novel mechanistic model of coupling c-ring- and ε rotation via a patch of hydrophobic residues in the NTD and residues of the CTD to the bottom of the catalytic α 3 β 3 -headpiece. To test our model, genome site-directed mutagenesis was employed to introduce amino acid changes in these two parts of the epsilon subunit. Inverted vesicle assays show that these mutations caused an increase in ATP hydrolysis activity and a reduction in ATP synthesis. The structural and enzymatic data are discussed in light of the transition mechanism of a compact and extended state of Mtε, which provides the inhibitory effects of this coupling subunit inside the rotary engine. Finally, the employment of these data with molecular docking shed light into the second binding site of the drug Bedaquiline. Structural data are available in the PDB under the accession number 5YIO. © 2018 Federation of European Biochemical Societies.

  2. A review of Curtiss-Wright rotary engine developments with respect to general aviation potential

    Science.gov (United States)

    Jones, C.

    1979-01-01

    Aviation related rotary (Wankel-type) engine tests, possible growth directions and relevant developments at Curtiss-Wright have been reviewed. Automotive rotary engines including stratified charge are described and flight test results of rotary aircraft engines are presented. The current 300 HP engine prototype shows basic durability and competitive performance potential. Recent parallel developments have separately confirmed the geometric advantages of the rotary engine for direct injected unthrottled stratified charge. Specific fuel consumption equal to or better than pre- or swirl-chamber diesels, low emission and multi-fuel capability have been shown by rig tests of similar rotary engine.

  3. Stratified charge rotary engine for general aviation

    Science.gov (United States)

    Mount, R. E.; Parente, A. M.; Hady, W. F.

    1986-01-01

    A development history, a current development status assessment, and a design feature and performance capabilities account are given for stratified-charge rotary engines applicable to aircraft propulsion. Such engines are capable of operating on Jet-A fuel with substantial cost savings, improved altitude capability, and lower fuel consumption by comparison with gas turbine powerplants. Attention is given to the current development program of a 400-hp engine scheduled for initial operations in early 1990. Stratified charge rotary engines are also applicable to ground power units, airborne APUs, shipboard generators, and vehicular engines.

  4. Rotary magnetic refrigerator for superfluid helium production

    International Nuclear Information System (INIS)

    Hakuraku, Y.; Ogata, H.

    1986-01-01

    A new rotary-magnetic refrigerator designed to obtain superfluid helium temperatures by executing a magnetic Carnot cycle is developed. A rotor containing 12 magnetic refrigerants (gadolinium-gallium-garnet) is immersed in liquid helium at 4.2 K and rotated at constant speed in a steady magnetic field distribution. Performance tests demonstrate that the new rotary refrigerator is capable of obtaining a temperature of 1.48 K. The maximum useful cooling power obtained at 1.8 K is 1.81 W which corresponds to a refrigeration efficiency of 34%

  5. Lift Production on Flapping and Rotary Wings at Low Reynolds Numbers

    Science.gov (United States)

    2016-02-26

    AFRL-AFOSR-VA-TR-2016-0098 Flapping and Rotary Wing Lift at Low Reynolds Number Anya Jones MARYLAND UNIV COLLEGE PARK Final Report 02/26/2016...Lift Production on Flapping and Rotary Wings at Low Reynolds Numbers (YIP) 5a. CONTRACT NUMBER 5b. GRANT NUMBER FA9550-12-1-0251 5c. PROGRAM...necessary if the abstract is to be limited. Standard Form 298 Back (Rev. 8/98) Lift Production on Flapping and Rotary Wings at Low Reynolds Numbers

  6. Leaching from waste incineration bottom ashes treated in a rotary kiln

    DEFF Research Database (Denmark)

    Hyks, Jiri; Nesterov, Igor; Mogensen, Erhardt

    2011-01-01

    Leaching from municipal solid waste incineration bottom ash treated in a rotary kiln was quantified using a combination of lab-scale leaching experiments and geochemical modelling. Thermal treatment in the rotary kiln had no significant effect on the leaching of Al, Ba, Ca, Mg, Si, Sr, Zn, sulfate...... the thermal treatment. Overall, rotary kiln thermal treatment of bottom ashes can be recommended to reduce the leaching of Cu, Pb, Cl and DOC; however, increased leaching of Cr and Mo should be expected....

  7. A reduced fidelity model for the rotary chemical looping combustion reactor

    KAUST Repository

    Iloeje, Chukwunwike O.; Zhao, Zhenlong; Ghoniem, Ahmed F.

    2017-01-01

    The rotary chemical looping combustion reactor has great potential for efficient integration with CO capture-enabled energy conversion systems. In earlier studies, we described a one-dimensional rotary reactor model, and used it to demonstrate

  8. Performance prediction of rotary compressor with hydrocarbon refrigerant mixtures

    Energy Technology Data Exchange (ETDEWEB)

    Park, M.W.; Chung, Y.G. [Hanyang University Graduate School, Seoul (Korea); Park, K.W. [LG Industrial System Corporation Limited (Korea); Park, H.Y. [Hanyang University, Seoul (Korea)

    1999-04-01

    This paper presents the modeling approach that can be predicted transient behavior of rotary compressor. Mass and energy conservation laws are applied to the control volume, and real gas state equation is used to obtain thermodynamic properties of refrigerant. The valve equation is solved to analyze discharge process also. Dynamic analysis of vane and roller is carried out to gain friction work. From above modeling, the performance of rotary compressor with radial clearance and friction loss is investigated numerically. The performance of each refrigerant and the possibility of using the hydrocarbon refrigerant mixtures in an existing rotary compressor are estimated by applying R12, R134a, R290/R600a mixture also. (author). 6 refs., 13 figs., 1 tab.

  9. "Dentinal microcracks after root canal preparation" a comparative evaluation with hand, rotary and reciprocating instrumentation.

    Science.gov (United States)

    Priya, N Tulasi; Chandrasekhar, Veeramachaneni; Anita, S; Tummala, Muralidhar; Raj, T B Phanindhar; Badami, Vijetha; Kumar, Pradeep; Soujanya, E

    2014-12-01

    The purpose of this study was to compare the incidence of dentinal micro cracks after instrumentation with various types of NiTi files in rotary and reciprocating motion. One hundred human extracted mandibular central incisors were taken and divided into 10 groups (n=10 teeth per group). Group 1- No preparation, Group 2 - Hand instrumentation, Groups 3,4 - ProTaper files in rotary and reciprocating motion, Groups 5,6 - ProTaper Next files in rotary and reciprocating motion, Groups 7,8 - Oneshape files in rotary and reciprocating motion, Groups 9,10 - Reciproc files in rotary and reciprocating motion. Specimens were sectioned horizontally at 3,6 and 9 mm from the apex and dentinal micro cracks were observed under a stereomicroscope. There was a statistically significant difference between the groups (pProtaper Next - Rot, Protaper Next - Rec, Reciproc - Rec); (ProTaper - Rot, ProTaper - Rec, Oneshape - Rot), (Oneshape - Rot, Reciproc - Rot), (One shape Reciproc, Reciproc - Rec); (p >.05). Least cracks were seen in canals instrumented with Pro Taper Next files both in rotary and reciprocating motion. Full sequence rotary systems showed less cracks than single file systems and full sequence rotary systems showed less cracks in reciprocating motion than in rotary motion.

  10. Rotary mode system initial instrument calibration

    International Nuclear Information System (INIS)

    Johns, B.R.

    1994-01-01

    The attached report contains the vendor calibration procedures used for the initial instrument calibration of the rotary core sampling equipment. The procedures are from approved vendor information files

  11. Dry rotary swaging with structured and coated tools

    Science.gov (United States)

    Herrmann, Marius; Schenck, Christian; Kuhfuss, Bernd

    2018-05-01

    Rotary swaging is a cold bulk forming process for manufacturing of complex bar and tube profiles like axles and gear shafts in the automotive industry. Conventional rotary swaging is carried out under intense use of lubricant usually based on mineral oil. Besides lubrication the lubricant fulfills necessary functions like lubrication, flushing and cooling, but generates costs for recycling, replacement and cleaning of the workpieces. Hence, the development of a dry process design is highly desirable, both under economic and ecological points of view. Therefore, it is necessary to substitute the functions of the lubricant. This was realized by the combination of newly developed a-C:H:W coating systems on the tools to minimize the friction and to avoid adhesion effects. With the application of a deterministic structure in the forging zone of the tools the friction conditions are modified to control the axial process forces. In this study infeed rotary swaging with functionalized tools was experimentally investigated. Therefore, steel and aluminum tubes were formed with and without lubricant. Different structures which were coated and uncoated were implemented in the reduction zone of the tools. The antagonistic effects of coating and structuring were characterized by measuring the axial process force and the produced workpiece quality in terms of roundness and surface roughness. Thus, the presented results allow for further developments towards a dry rotary swaging process.

  12. Development of a rotary clap mechanism for positive-displacement rotary pumps: Kinematic analysis and working principle

    International Nuclear Information System (INIS)

    Shim, Sung Bo; Kim, Kyeong Uk; Park, Young Jun; Kim, Jong Mun

    2015-01-01

    A five-bar spatial mechanism named as a rotary clap mechanism is developed as a pumping device for positive displacement rotary pumps. The mechanism comprises a driving crank, a shaft link with two pins and two gears mounted on the middle and both ends, two rotors with jaws equally spaced along their circumferences, and two fixed internal gears. As the crank rotates, the gear pin-jointed to the crank rotates about the crank pin and at the same time rotates about the center of the fixed internal gears like a hypo-cyclic gear train. The gear-attached shaft link also rotates about the crank pin and about the fixed internal gears at the same time. This motion of the shaft link makes the pins rotate about the center of the fixed internal gears with a periodically varying radius. Therefore, two rotors driven by the pins rotate with different angular velocities. One rotor alternately leads and lags relative to the other rotor. These lead-lag motions between the two jaws of the rotors, which result in suction and discharge required for pumping, resemble hand clapping from which the mechanism was named. Construction and design parameters of the rotary clap mechanism are introduced, and kinematic analysis of this mechanism is performed. The relationships among design parameters, inherent constraints, and effects of design parameters on the is placement of mechanism are also presented.

  13. Rotary magnetic heat pump

    Science.gov (United States)

    Kirol, L.D.

    1987-02-11

    A rotary magnetic heat pump constructed without flow seals or segmented rotor accomplishes recuperation and regeneration by using split flow paths. Heat exchange fluid pumped through heat exchangers and returned to the heat pump splits into two flow components: one flowing counter to the rotor rotation and one flowing with the rotation. 5 figs.

  14. Rotary mode core sampling approved checklist: 241-TX-113

    International Nuclear Information System (INIS)

    Fowler, K.D.

    1998-01-01

    The safety assessment for rotary mode core sampling was developed using certain bounding assumptions, however, those assumptions were not verified for each of the existing or potential flammable gas tanks. Therefore, a Flammable Gas/Rotary Mode Core Sampling Approved Checklist has been completed for tank 241-TX-113 prior to sampling operations. This transmittal documents the dispositions of the checklist items from the safety assessment

  15. Rotary mode core sampling approved checklist: 241-TX-116

    International Nuclear Information System (INIS)

    FOWLER, K.D.

    1999-01-01

    The safety assessment for rotary mode core sampling was developed using certain bounding assumptions, however, those assumptions were not verified for each of the existing or potential flammable gas tanks. Therefore, a Flammable Gas/Rotary Mode Core Sampling Approved Checklist has been completed for tank 241-TX-116 prior to sampling operations. This transmittal documents the dispositions of the checklist items from the safety assessment

  16. Asymmetric free vibrations of laminated annular cross-ply circular plates including the effects of shear deformation and rotary inertia. Spline method

    Energy Technology Data Exchange (ETDEWEB)

    Viswanathan, K.K.; Kim, Kyung Su; Lee, Jang Hyun [Inha Univ., Incheon (Korea). Dept. of Naval Architecture and Ocean Engineering

    2009-12-15

    Asymmetric free vibrations of annular cross-ply circular plates are studied using spline function approximation. The governing equations are formulated including the effects of shear deformation and rotary inertia. Assumptions are made to study the cross-ply layered plates. A system of coupled differential equations are obtained in terms of displacement functions and rotational functions. These functions are approximated using Bickley- type spline functions of suitable order. Then the system is converted into the eigenvalue problem by applying the point collocation technique and suitable boundary conditions. Parametric studies have been made to investigate the effect of transverse shear deformation and rotary inertia on frequency parameter with respect to the circumferential node number, radii ratio and thickness to radius ratio for both symmetric and anti-symmetric cross-ply plates using various types of material properties. (orig.)

  17. Multi-Fuel Rotary Engine for General Aviation Aircraft

    Science.gov (United States)

    Jones, C.; Ellis, D. R.; Meng, P. R.

    1983-01-01

    Design studies, conducted for NASA, of Advanced Multi-fuel General Aviation and Commuter Aircraft Rotary Stratified Charge Engines are summarized. Conceptual design studies of an advanced engine sized to provide 186/250 shaft KW/HP under cruise conditions at 7620/25,000 m/ft. altitude were performed. Relevant engine development background covering both prior and recent engine test results of the direct injected unthrottled rotary engine technology, including the capability to interchangeably operate on gasoline, diesel fuel, kerosene, or aviation jet fuel, are presented and related to growth predictions. Aircraft studies, using these resultant growth engines, define anticipated system effects of the performance and power density improvements for both single engine and twin engine airplanes. The calculated results indicate superior system performance and 30 to 35% fuel economy improvement for the Rotary-engine airplanes as compared to equivalent airframe concept designs with current baseline engines. The research and technology activities required to attain the projected engine performance levels are also discussed.

  18. Generation of rotary vibrations in internal combustion engines with elastically coupled electric power systems; Erzeugung von verbrennungsmotorischen Drehschwingungen mit elastisch gekoppelten elektrischen Antrieben

    Energy Technology Data Exchange (ETDEWEB)

    Falkenstein, Jens Werner [Rostock Univ. (Germany). Inst. fuer Antriebstechnik und Mechatronik

    2004-07-01

    The design of motor car powertrains requires simulations as well as prototype tests. For the simulations, prototype parameters must be identified on test rigs, simulation results must be verified, and life tests must be carried out. This necessitates realistic and reproducible excitation of vibrations. Thee book describes the development and construction of a test rig which, with the aid of electric power systems, induces rotary vibrations like those which may occur in internal combustion engines due to gas forces and unbalanced mass forces. In combination with excess resonance, the test stand achieves high dynamics with average rotary momenta up to 600 Nm. The development process is documented, from test stand design with specially developed servo-engines to the control hardware to modelling, control element design, and commissioning. (orig.)

  19. Application of a magnetic fluid seal to rotary blood pumps

    International Nuclear Information System (INIS)

    Mitamura, Y; Arioka, S; Azegami, M; Sakota, D; Sekine, K

    2008-01-01

    A magnetic fluid seal enables mechanical contact-free rotation of a shaft without frictional heat and material wear and hence has excellent durability. However, the durability of a magnetic fluid seal decreases in liquid. The life of a seal applied to a rotary blood pump is not known. We have developed a magnetic fluid seal that has a shield mechanism minimizing the influence of the rotary pump on the magnetic fluid. The developed magnetic fluid seal worked for over 286 days in a continuous flow condition, for 24 days (on-going) in a pulsatile flow condition and for 24 h (electively terminated) in blood flow. The magnetic fluid seal is promising as a shaft seal for rotary blood pumps

  20. Ka-band waveguide rotary joint

    KAUST Repository

    Yevdokymov, Anatoliy; Sirenko, Kostyantyn; Kryzhanovskiy, Volodymyr; Pazynin, Vadim

    2013-01-01

    The authors present a design of a waveguide rotary joint operating in Ka-band with central frequency of 33 GHz, which also acts as an antenna mount. The main unit consists of two flanges with a clearance between them; one of the flanges has three

  1. Design and experimental tests of a rotary active magnetic regenerator prototype

    DEFF Research Database (Denmark)

    Eriksen, Dan; Engelbrecht, Kurt; Bahl, Christian

    2015-01-01

    A rotary active magnetic regenerator (AMR) prototype with efficiency and compact design as focus points has been designed and built. The main objective is to demonstrate improved efficiency for rotary devices by reducing heat leaks from the environment and parasitic mechanical work losses while...

  2. Recent developments in rotary-wing aerodynamic theory

    Science.gov (United States)

    Johnson, W.

    1986-01-01

    Current progress in the computational analysis of rotary-wing flowfields is surveyed, and some typical results are presented in graphs. Topics examined include potential theory, rotating coordinate systems, lifting-surface theory (moving singularity, fixed wing, and rotary wing), panel methods (surface singularity representations, integral equations, and compressible flows), transonic theory (the small-disturbance equation), wake analysis (hovering rotor-wake models and transonic blade-vortex interaction), limitations on computational aerodynamics, and viscous-flow methods (dynamic-stall theories and lifting-line theory). It is suggested that the present algorithms and advanced computers make it possible to begin working toward the ultimate goal of turbulent Navier-Stokes calculations for an entire rotorcraft.

  3. Conditioning of material properties by micro rotary swaging

    Science.gov (United States)

    Ishkina, Svetlana; Schenck, Christian; Kuhfuss, Bernd

    2018-05-01

    Cold forming initiates a change of the material properties like flow stress and hardness. Due to work hardening and the accompanied loss of formability some intermediate heat treatment may become necessary in multi-stage forming processes. One possibility to avoid this heat treatment is to adjust the forming characteristics in terms of flow stress and formability by rotary swaging. This process is particularly suitable not only for producing of the target geometry but also for modifying of the material properties during the process and thus, rotary swaging can prepare the parts for further forming, such as extrusion. In this contribution, the process chain "rotary swaging - extrusion" for austenite stainless steel AISI304 was investigated. The forming characteristics of the semi-finished products for the extrusion were influenced by the previous swaging process. The conditioning by changing of the microstructure, the work hardening and the geometry of the processed wires was achieved by the process design. For this purpose, the geometry of the swaging dies, the feeding velocity as well as the process kinematics (eccentric swaging) and a stroke following angle Δɸ were varied. In particular, the novel geometry of the swaging dies with extraordinary sloped faces generated a non-symmetric material flow with severe shear deformation and thus an extreme change of the microstructure. The required forming force of the following extrusion process reflected the range of achievable conditioning. The micro rotary swaging process positively improved the formability of AISI304 by work softening.

  4. Inter renewal travelling wave reactor with rotary fuel columns

    International Nuclear Information System (INIS)

    Terai, Yuzo

    2016-01-01

    To realize the COP21 decision, this paper proposes Inter Renewal Travelling Wave Reactor that bear high burn-up rate 50% and product TRU fuel efficiently. The reactor is based on 4S Fast Reactor and has Reactor Fuel Columns as fuel assemblies that equalize temperature in the fuel assembly so that fewer structure is need to restrain thermal transformation. To equalize burn-up rate of all fuel assemblies in the reactor, each rotary fuel column has each motor-lifter. The rotary fuel column has two types (Cylinder type and Heat Pipe type using natrium at 15 kPa which supply high temperature energy for Ultra Super Critical power plant). At 4 years cycle all rotary fuel columns of the reactor are renewed by the metallurgy method (vacuum re-smelting) and TRU fuel is gotten from the water fuel. (author)

  5. Conceptual Study of Rotary-Wing Microrobotics

    National Research Council Canada - National Science Library

    Chabak, Kelson D

    2008-01-01

    This thesis presents a novel rotary-wing micro-electro-mechanical systems (MEMS) robot design. Two MEMS wing designs were designed, fabricated and tested including one that possesses features conducive to insect level aerodynamics...

  6. Rotary piston blood pumps: past developments and future potential of a unique pump type.

    Science.gov (United States)

    Wappenschmidt, Johannes; Autschbach, Rüdiger; Steinseifer, Ulrich; Schmitz-Rode, Thomas; Margreiter, Raimund; Klima, Günter; Goetzenich, Andreas

    2016-08-01

    The design of implantable blood pumps is either based on displacement pumps with membranes or rotary pumps. Both pump types have limitations to meet the clinical requirements. Rotary piston blood pumps have the potential to overcome these limitations and to merge the benefits. Compared to membrane pumps, they are smaller and with no need for wear-affected membranes and valves. Compared to rotary pumps, the blood flow is pulsatile instead of a non-physiological continuous flow. Furthermore, the risk of flow-induced blood damage and platelet activation may be reduced due to low shear stress to the blood. The past developments of rotary piston blood pumps are summarized and the main problem for long-term application is identified: insufficient seals. A new approach with seal-less drives is proposed and current research on a simplified rotary piston design is presented. Expert commentary: The development of blood pumps focuses mainly on the improvement of rotary pumps. However, medical complications indicate that inherent limitations of this pump type remain and restrict the next substantial step forward in the therapy of heart failure patients. Thus, research on different pump types is reasonable. If the development of reliable drives and bearings succeeds, rotary piston blood pumps become a promising alternative.

  7. Rotary condenser for SC2

    CERN Multimedia

    1975-01-01

    During 1975 the SC2 performance was improved among other things by redesigning some of the elements of the ROTCO (Annual Report 1975, p. 55). The photo shows an interior wiew of the housing of the rotary condenser and of the sixteen sets of shaped stator blades.

  8. Thermal energy analysis of a lime production process: Rotary kiln, preheater and cooler

    International Nuclear Information System (INIS)

    Shahin, Hamed; Hassanpour, Saeid; Saboonchi, Ahmad

    2016-01-01

    Highlights: • The integrated model for lime production unit which includes cooler, preheater and rotary kiln is developed. • The effect of residence time in each section on efficiency is investigated. • Influence of material feed rate and excess air on specific fuel consumption is analyzed. • The significant effect of particle size on efficiency and specific fuel consumption is shown. - Abstract: In this paper, thermal energy analysis of three zones of a lime production process, which are preheater, rotary kiln and cooler, is performed. In order to perform a proper quantitative estimation, the system was modeled using energy balance equations including coupled heat transfer and chemical reaction mechanisms. A mathematical model was developed, and consequently, the thermal and chemical behavior of limestone was investigated. The model was verified using empirical data. After model confirmation, the variation of Specific Fuel Consumption (SFC) versus production rate was predicted and the optimum condition was determined. Subsequently, fuel consumption was calculated regarding to altered residence time inside each zone of lime production process, for a constant output. Results indicate that increasing the residence time inside each zone of lime production process, will enhance thermal efficiency and saves fuel consumption. Relative enhancement will be the same for different sizes of limestone. It was found that a 10-min increase in material residence time inside the preheater or rotary kiln can reduce fuel consumption by around two percent. Whereas, a 5-min increase in material residence time inside the cooler would be enough to obtain a similar result. Finally, the ratio of air-to-fuel and production rate are changed in such a way that the same product is achieved. The model predicts that lowering excess air from 15% to 10% leads to a 2.5% reduction of Specific Fuel Consumption (SFC).

  9. Rotary Balance Wind Tunnel Testing for the FASER Flight Research Aircraft

    Science.gov (United States)

    Denham, Casey; Owens, D. Bruce

    2016-01-01

    Flight dynamics research was conducted to collect and analyze rotary balance wind tunnel test data in order to improve the aerodynamic simulation and modeling of a low-cost small unmanned aircraft called FASER (Free-flying Aircraft for Sub-scale Experimental Research). The impetus for using FASER was to provide risk and cost reduction for flight testing of more expensive aircraft and assist in the improvement of wind tunnel and flight test techniques, and control laws. The FASER research aircraft has the benefit of allowing wind tunnel and flight tests to be conducted on the same model, improving correlation between wind tunnel, flight, and simulation data. Prior wind tunnel tests include a static force and moment test, including power effects, and a roll and yaw damping forced oscillation test. Rotary balance testing allows for the calculation of aircraft rotary derivatives and the prediction of steady-state spins. The rotary balance wind tunnel test was conducted in the NASA Langley Research Center (LaRC) 20-Foot Vertical Spin Tunnel (VST). Rotary balance testing includes runs for a set of given angular rotation rates at a range of angles of attack and sideslip angles in order to fully characterize the aircraft rotary dynamics. Tests were performed at angles of attack from 0 to 50 degrees, sideslip angles of -5 to 10 degrees, and non-dimensional spin rates from -0.5 to 0.5. The effects of pro-spin elevator and rudder deflection and pro- and anti-spin elevator, rudder, and aileron deflection were examined. The data are presented to illustrate the functional dependence of the forces and moments on angle of attack, sideslip angle, and angular rate for the rotary contributions to the forces and moments. Further investigation is necessary to fully characterize the control effectors. The data were also used with a steady state spin prediction tool that did not predict an equilibrium spin mode.

  10. Performance of rotary kiln reactor for the elephant grass pyrolysis.

    Science.gov (United States)

    De Conto, D; Silvestre, W P; Baldasso, C; Godinho, M

    2016-10-01

    The influence of process conditions (rotary speed/temperature) on the performance of a rotary kiln reactor for non-catalytic pyrolysis of a perennial grass (elephant grass) was investigated. The product yields, the production of non-condensable gases as well as the biochar properties were evaluated. The maximum H2 yield was close to that observed for catalytic pyrolysis processes, while the bio-oil yield was higher than reported for pyrolysis of other biomass in rotary kiln reactors. A H2/CO ratio suitable for Fischer-Tropsch synthesis (FTS) was obtained. The biochars presented an alkaline pH (above 10) and interesting contents of nutrients, as well as low electrical conductivity, indicating a high potential as soil amendment. Copyright © 2016 Elsevier Ltd. All rights reserved.

  11. Development status of rotary engine at Toyo Kogyo. [for general aviation aircraft

    Science.gov (United States)

    Yamamoto, K.

    1978-01-01

    Progress in the development of rotary engines which use a thermal reactor as the primary part of the exhaust emission control system is reviewed. Possibilities of further improvements in fuel economy of future rotary engines are indicated.

  12. Dynamic Modeling and Analysis of the Large-Scale Rotary Machine with Multi-Supporting

    Directory of Open Access Journals (Sweden)

    Xuejun Li

    2011-01-01

    Full Text Available The large-scale rotary machine with multi-supporting, such as rotary kiln and rope laying machine, is the key equipment in the architectural, chemistry, and agriculture industries. The body, rollers, wheels, and bearings constitute a chain multibody system. Axis line deflection is a vital parameter to determine mechanics state of rotary machine, thus body axial vibration needs to be studied for dynamic monitoring and adjusting of rotary machine. By using the Riccati transfer matrix method, the body system of rotary machine is divided into many subsystems composed of three elements, namely, rigid disk, elastic shaft, and linear spring. Multiple wheel-bearing structures are simplified as springs. The transfer matrices of the body system and overall transfer equation are developed, as well as the response overall motion equation. Taken a rotary kiln as an instance, natural frequencies, modal shape, and response vibration with certain exciting axis line deflection are obtained by numerical computing. The body vibration modal curves illustrate the cause of dynamical errors in the common axis line measurement methods. The displacement response can be used for further measurement dynamical error analysis and compensation. The response overall motion equation could be applied to predict the body motion under abnormal mechanics condition, and provide theory guidance for machine failure diagnosis.

  13. Tuned dynamics stabilizes an idealized regenerative axial-torsional model of rotary drilling

    Science.gov (United States)

    Gupta, Sunit K.; Wahi, Pankaj

    2018-01-01

    We present an exact stability analysis of a dynamical system idealizing rotary drilling. This system comprises lumped parameter axial-torsional modes of the drill-string coupled via the cutting forces and torques. The kinematics of cutting is modeled through a functional description of the cut surface which evolves as per a partial differential equation (PDE). Linearization of this model is straightforward as opposed to the traditional state-dependent delay (SDDE) model and both the approaches result in the same characteristic equation. A systematic study on the key system parameters influencing the stability characteristics reveals that torsional damping is very critical and stable drilling is, in general, not possible in its absence. The stable regime increases as the natural frequency of the axial mode approaches that of the torsional mode and a 1:1 internal resonance leads to a significant improvement in the system stability. Hence, from a practical point of view, a drill-string with 1:1 internal resonance is desirable to avoid vibrations during rotary drilling. For the non-resonant case, axial damping reduces the stable range of operating parameters while for the resonant case, an optimum value of axial damping (equal to the torsional damping) results in the largest stable regime. Interestingly, the resonant (tuned) system has a significant parameter regime corresponding to stable operation even in the absence of damping.

  14. Mechanical design of a rotary balance system for NASA. Langley Research Center's vertical spin tunnel

    Science.gov (United States)

    Allred, J. W.; Fleck, V. J.

    1992-01-01

    A new lightweight Rotary Balance System is presently being fabricated and installed as part of a major upgrade to the existing 20 Foot Vertical Spin Tunnel. This upgrade to improve model testing productivity of the only free spinning vertical wind tunnel includes a modern fan/drive and tunnel control system, an updated video recording system, and the new rotary balance system. The rotary balance is a mechanical apparatus which enables the measurement of aerodynamic force and moment data under spinning conditions (100 rpm). This data is used in spin analysis and is vital to the implementation of large amplitude maneuvering simulations required for all new high performance aircraft. The new rotary balance system described in this report will permit greater test efficiency and improved data accuracy. Rotary Balance testing with the model enclosed in a tare bag can also be performed to obtain resulting model forces from the spinning operation. The rotary balance system will be stored against the tunnel sidewall during free flight model testing.

  15. Rotary drum for distilling bituminous material

    Energy Technology Data Exchange (ETDEWEB)

    1921-11-02

    A rotary drum with insert tubes for distilling bituminous materials, like mineral coal, brown coal, wood, peat, and oil-shale, is characterized in that the insert tube is heated also by superheated steam introduced into the drum.

  16. A Thermoelectric Waste-Heat-Recovery System for Portland Cement Rotary Kilns

    Science.gov (United States)

    Luo, Qi; Li, Peng; Cai, Lanlan; Zhou, Pingwang; Tang, Di; Zhai, Pengcheng; Zhang, Qingjie

    2015-06-01

    Portland cement is produced by one of the most energy-intensive industrial processes. Energy consumption in the manufacture of Portland cement is approximately 110-120 kWh ton-1. The cement rotary kiln is the crucial equipment used for cement production. Approximately 10-15% of the energy consumed in production of the cement clinker is directly dissipated into the atmosphere through the external surface of the rotary kiln. Innovative technology for energy conservation is urgently needed by the cement industry. In this paper we propose a novel thermoelectric waste-heat-recovery system to reduce heat losses from cement rotary kilns. This system is configured as an array of thermoelectric generation units arranged longitudinally on a secondary shell coaxial with the rotary kiln. A mathematical model was developed for estimation of the performance of waste heat recovery. Discussions mainly focus on electricity generation and energy saving, taking a Φ4.8 × 72 m cement rotary kiln as an example. Results show that the Bi2Te3-PbTe hybrid thermoelectric waste-heat-recovery system can generate approximately 211 kW electrical power while saving 3283 kW energy. Compared with the kiln without the thermoelectric recovery system, the kiln with the system can recover more than 32.85% of the energy that used to be lost as waste heat through the kiln surface.

  17. Rotary's PolioPlus Program: Lessons Learned, Transition Planning, and Legacy.

    Science.gov (United States)

    Sever, John L; McGovern, Michael; Scott, Robert; Pandak, Carol; Edwards, Amy; Goodstone, David

    2017-07-01

    Hundreds of thousands of Rotary volunteers have provided support for polio eradication activities and continue to this day by making financial contributions to the Rotary PolioPlus program, participating in national immunization days, assisting with surveillance, working on local, national, and international advocacy programs for polio eradication, assisting at immunization posts and clinics, and mobilizing their communities for immunization activities (including poliovirus and other vaccines) and other health benefits. Rotary has contributed more than $1.61 billion for the global eradication of polio and has committed to provide an additional $35 million each year until 2018 (all dollar amounts represent US dollars). Its unwavering commitment to eradicate polio has been vital to the success of the program. Rotary is providing additional support for routine immunization and healthcare. When polio is finally gone, we will have the knowledge from the lessons learned with PolioPlus, such as the value of direct involvement by local Rotarians, the program for emergency funding, innovative tactics, and additional approaches for tackling other global issues, even those beyond public health. Rotary has already transitioned its grants program to include 6 areas of focus: disease prevention and treatment, water and sanitation, maternal and child health, basic education and literacy, economic and community development, and peace and conflict prevention/resolution. Funding for these grants in 2015-2016 was $71 million. The legacy of the polio program will be the complete eradication of poliovirus and the elimination of polio for all time. © The Author 2017. Published by Oxford University Press for the Infectious Diseases Society of America.

  18. Comparison between rotary and manual instrumentation in primary teeth.

    Science.gov (United States)

    Crespo, S; Cortes, O; Garcia, C; Perez, L

    2008-01-01

    The aim of this study was to compare the efficiency in both, preparation time and root canal shape, when using the Nickel Titanium (Ni-Ti) rotary and K-Files hand instrumentation on root canal preparation of single rooted primary teeth. Sixty single rooted primary teeth were selected and divided into two equal groups: Group (I) 30 teeth instrumented with manual K-files and group (II) 30 teeth instrumented with Ni-Ti rotary files (ProFile 0.04). Instrumentation times were calculated and root canal impressions were taken with light bodied silicone in order to evaluate the shape. The data was analyzed with SPSS program using the t-test and the Chi-square test to compare their means. The preparation time with group (I) K-files was significantly higher than in group (II) rotary files (ProFile 0.04), with a p= .005. The ProFile system showed a significantly more favorable canal taper when compared to the K-files system (P= .002). The use of rotary files in primary teeth has several advantages when compared with manual K files: the efficiency in both, preparation time and root canal shape. 1. A decreased working time, that helps maintain patient cooperation by diminishing the potential for tiredness. 2. The shape of the root canal is more conical, favoring a higher quality of the root canal filling, and increasing clinical success.

  19. [In vitro comparison of root canal preparation with step-back technique and GT rotary file--a nickel-titanium engine driven rotary instrument system].

    Science.gov (United States)

    Krajczár, Károly; Tóth, Vilmos; Nyárády, Zoltán; Szabó, Gyula

    2005-06-01

    The aim of the authors' study was to compare the remaining root canal wall thickness and the preparation time of root canals, prepared either with step-back technique, or with GT Rotary File, an engine driven nickel-titanium rotary instrument system. Twenty extracted molars were decoronated. Teeth were divided in two groups. In Group 1 root canals were prepared with step-back technique. In Group 2 GT Rotary File System was utilized. Preoperative vestibulo-oral X-ray pictures were taken from all teeth with radiovisiograph (RVG). The final preparations at the mesiobuccal canals (MB) were performed with size #30 and palatinal/distal canals with size #40 instruments. Postoperative RVG pictures were taken ensuring the preoperative positioning. The working time was measured in seconds during each preparation. The authors also assessed the remaining root canal wall thickness at 3, 6 and 9 mm from the radiological apex, comparing the width of the canal walls of the vestibulo-oral projections on pre- and postoperative RVG pictures both mesially and buccally. The ratios of the residual and preoperative root canal wall thickness were calculated and compared. The largest difference was found at the MB canals of the coronal and middle third level of the root, measured on the distal canal wall. The ratio of the remaining dentin wall thickness at the coronal and the middle level in the case of step-back preparation was 0.605 and 0.754, and 0.824 and 0.895 in the cases of GT files respectively. The preparation time needed for GT Rotary File System was altogether 68.7% (MB) and 52.5% (D/P canals) of corresponding step-back preparation times. The use of GT Rotary File with comparison of standard step-back method resulted in a shortened preparation time and excessive damage of the coronal part of the root canal could be avoided.

  20. Design and development of a rotary calciner for radiochemical waste

    International Nuclear Information System (INIS)

    Pande, D.P.; Sutar, V.D.; Sengar, P.B.S.

    1997-01-01

    Present experience and knowledge in handling of radioactive waste has led to identification of major thrust areas in the development of the treatment processes. In order to reduce evaporation and volatility losses in the vitrification facility, it is advantageous to carry out evaporation and calcination steps in another equipment like rotary calciner. Efforts have been directed for the engineering development of a Rotary Ball Kiln calciner. This paper highlights the important design features of the Rotary Ball Kiln Calciner for the radioactive waste. In this work, an attempt has been made to systematically evaluate the influence of process and design parameters. The results obtained on calcination will provide a design basis and rational methodology for the optimum utilization of these processes and equipment for volume reduction and calcination of the liquid waste

  1. High-resolution gas-phase spectroscopy of a single-bond axle rotary motor

    NARCIS (Netherlands)

    Maltseva, Elena; Amirjalayer, Saeed; Cnossen, Arjen; Browne, Wesley R.; Feringa, Ben L.; Buma, Wybren Jan

    2017-01-01

    High-resolution laser spectroscopy in combination with molecular beams and mass-spectrometry has been applied to study samples of a prototypical rotary motor. Vibrationally well-resolved excitation spectra have been recorded that are assigned, however, to a structural isomer of the original rotary

  2. Rotary plug device for use in LMFBR type reactors

    International Nuclear Information System (INIS)

    Azuma, Kazuhiko; Imayoshi, Sho.

    1988-01-01

    Purpose: To prevent adhesion of sodium in the rotational gap of a rotational plug. Constitution: One of the walls of a cylindrical gap formed between the outer circumference of a small rotary plug and a large rotary plug that constitute a double rotary plug is cooled to lower than the sodium coagulation temperature, while a stater of a linear motor in a cylindrical shape and wound with linear coils around the iron core is attached to the inside of the other of the walls. Then, one of the walls of the gap to which sodium adheres is cooled to less than sodium coagulation temperature, so that sodium is or tends to be deposited to the wall. Then, eddy currents are resulted to sodium by the current supplied to the stater of the linear motor attached to the other of the walls, to produce thrusting force. Sodium on the wall surface is scraped off by this. (Yoshihara, H.)

  3. Magnetic hardening of Fe{sub 50}Co{sub 50} by rotary swaging

    Energy Technology Data Exchange (ETDEWEB)

    Gröb, T., E-mail: t.groeb@phm.tu-darmstadt.de [Division Physical Metallurgy, Alarich-Weiß-Str. 2, 64287 Darmstadt (Germany); Wießner, L. [Institute for Production Engineering and Forming Machines, Otto-Berndt-Str. 2, 64287 Darmstadt (Germany); Bruder, E. [Division Physical Metallurgy, Alarich-Weiß-Str. 2, 64287 Darmstadt (Germany); Faske, T.; Donner, W. [Divison Structure Research, Alarich-Weiß-Str. 2, 64287 Darmstadt (Germany); Groche, P. [Institute for Production Engineering and Forming Machines, Otto-Berndt-Str. 2, 64287 Darmstadt (Germany); Müller, C. [Division Physical Metallurgy, Alarich-Weiß-Str. 2, 64287 Darmstadt (Germany)

    2017-04-15

    Fe{sub 50}Co{sub 50} was subjected to incremental forming by rotary swaging with the aim of tailoring the coercivity by changing the microstructure. The challenging part of a deformation of Fe{sub 50}Co{sub 50} is an ordering phase present at room temperature, leading to low formability. To increase the formability of the alloy the presence of the ordering phase was supressed by two different concepts. The first concept consists of a heat treatment above the phase transition followed by rapid cooling and deformation at room temperature. The second concept was rotary swaging at temperatures above the phase transition temperature. A comparison in terms of resulting microstructure and magnetic properties shows that both concepts have a potential for tailoring the coercivity of Fe{sub 50}Co{sub 50}. - Highlights: • Magnetic hardening of Fe{sub 50}Co{sub 50} was achieved by rotary swaging with two different concepts. • The influences of the microstructural changes during the rotary swaging process have been linked to magnetic hardening. • Increase in coercivity for Fe{sub 50}Co{sub 50} by rotary swaging at elevated temperature is limited by the dynamic restoration. • Coercivity of Fe{sub 50}Co{sub 50} can be tailored by the induced plastic strain.

  4. A Survey on Nickel Titanium Rotary Instruments and their Usage Techniques by Endodontists in India.

    Science.gov (United States)

    Patil, Thimmanagowda N; Saraf, Prahlad A; Penukonda, Raghavendra; Vanaki, Sneha S; Kamatagi, Laxmikant

    2017-05-01

    The preference and usage of nickel titanium rotary instruments varies from individual to individual based on their technique, experience with the rotary systems and the clinical situation. Very limited information is available to explain the adoption of changing concepts with respect to nickel titanium rotary instruments pertaining to the endodontists in India. The aim of this study was to conduct a questionnaire survey to acquire the knowledge concerning different NiTi rotary instruments and their usage techniques by endodontists in India. A Survey questionnaire was designed which consisted of 32 questions regarding designation, demographics, experience with rotary instruments, usage of different file systems, usage techniques, frequency of reuse, occurrence of file fracture, reasons and their management was distributed by hand in the national postgraduate convention and also disseminated via electronic medium to 400 and 600 endodontists respectively. Information was collected from each individual to gain insight into the experiences and beliefs of endodontists concerning the new endodontic technology of rotary NiTi instrumentation based on their clinical experience with the rotary systems. The questions were designed to ascertain the problems, patterns of use and to identify areas of perceived or potential concern regarding the rotary instruments and the data acquired was statistically evaluated using Fisher's-exact test and the Chi-Square test. Overall 63.8% (638) endodontists responded. ProTaper was one of the most commonly used file system followed by M two and ProTaper Next. There was a significant co relation between the years of experience and the file re use frequency, preparation technique, file separation, management of file separation. A large number of Endodontists prefer to reuse the rotary NiTi instruments. As there was an increase in the experience, the incidence of file separation reduced with increasing number of re use frequency and with

  5. Distribution of Microstructure and Vickers Hardness in Spur Bevel Gear Formed by Cold Rotary Forging

    Directory of Open Access Journals (Sweden)

    Wuhao Zhuang

    2014-11-01

    Full Text Available Cold rotary forging is a novel metal forming technology which is widely used to produce the high performance gears. Investigating the microstructure and mechanical property of cold rotary forged gears has a great significance in improving their service performance. In this study, the grain morphology in different regions of the spur bevel gear which is processed by cold rotary forging is presented. And the distribution regulars of the grain deformation and Vickers hardness in the transverse and axial sections of the gear tooth are studied experimentally. A three-dimensional rigid-plastic FE model is developed to simulate the cold rotary forging process of a spur bevel gear under the DEFORM-3D software environment. The variation of effective strain in the spur bevel gear has been investigated so as to explain the distribution regulars of the microstructure and Vickers hardness. The results of this research thoroughly reveal the inhomogeneous deformation mechanisms in cold rotary forging of spur bevel gears and provide valuable guidelines for improving the performance of cold rotary forged spur bevel gears.

  6. Rotary Mode Core Sample System availability improvement

    International Nuclear Information System (INIS)

    Jenkins, W.W.; Bennett, K.L.; Potter, J.D.; Cross, B.T.; Burkes, J.M.; Rogers, A.C.

    1995-01-01

    The Rotary Mode Core Sample System (RMCSS) is used to obtain stratified samples of the waste deposits in single-shell and double-shell waste tanks at the Hanford Site. The samples are used to characterize the waste in support of ongoing and future waste remediation efforts. Four sampling trucks have been developed to obtain these samples. Truck I was the first in operation and is currently being used to obtain samples where the push mode is appropriate (i.e., no rotation of drill). Truck 2 is similar to truck 1, except for added safety features, and is in operation to obtain samples using either a push mode or rotary drill mode. Trucks 3 and 4 are now being fabricated to be essentially identical to truck 2

  7. Tallinna Rotary klubi valis aasta politseiniku ja narkokoera

    Index Scriptorium Estoniae

    2006-01-01

    Tallinna Rotary klubi autasustas parima narkopolitseiniku preemiaga Lõuna politseiprefektuuri narkokuritegude talituse vaneminspektorit Jarek Pavlihhinit ning parima narkokoera tiitliga vene spanjelit Allrighti

  8. Rotary kiln arrangements

    International Nuclear Information System (INIS)

    Hayes, M.R.

    1983-01-01

    In a rotary kiln arrangement in which a reaction is to occur between counterflowing reactants and material is discharged through a hopper, an injector for at least one reactant extends into a reaction zone of the kiln, means being provided for the reaction zone to be maintained within a desired temperature range. The said means includes heating elements for adjusting the temperature of the injected reactant to a temperature within the desired range while it is in the injector. The arrangement may be used in the production of uranium oxides from uranium hexafluoride. (author)

  9. Undergraduates’ opinion after 5-year experience with rotary endodontic instruments

    OpenAIRE

    Flávia Sens Fagundes Tomazinho; Gisele Aihara Haragushiku; Flares Baratto Filho; Denise Piotto Leonardi; Maria da Graça Kfouri Lopes; Alexandre Moro

    2011-01-01

    Introduction: Dentistry evolution in the past few years has revolutionized daily practice in some specialties. One of these revolutions has occurred in Endodontics due to the advancement of rotary techniques for root canal preparation and its subsequent incorporation into the teaching of Dentistry undergraduates. Objective: The aim of this study was to report a 5-year experience on the undergraduate laboratorial and clinical use of rotary endodontic preparation at a private university. Materi...

  10. Simulation of Stress-Strain State of Shovel Rotary Support Kingpin

    Science.gov (United States)

    Khoreshok, A. A.; Buyankin, P. V.; Vorobiev, A. V.; Dronov, A. A.

    2016-04-01

    The article presents the sequence of computational simulation of stress-strain state of shovel’s rotary support. Computation results are analyzed, the kingpin is specified as the most loaded element, maximum stress zones are identified. Kingpin design modification such as enhancement of fillet curvature radius to 25 mm and displacement of eyebolt holes on the diameter of 165 mm are proposed, thus diminishing impact of stress concentrators and improving reliability of the rotary support.

  11. Glass: Rotary Electric Glass Furnace

    Energy Technology Data Exchange (ETDEWEB)

    Recca, L.

    1999-01-29

    Compared to conventional gas-fired furnaces, the new rotary electric furnace will increase energy efficiency while significantly reducing air emissions, product turnaround time, and labor costs. As this informative new fact sheet explains, the thousand different types of glass optical blanks produced for the photonics industry are used for lasers, telescopes, cameras, lights, and many other products.

  12. Performance characterization of Watson Ahumada motion detector using random dot rotary motion stimuli.

    Directory of Open Access Journals (Sweden)

    Siddharth Jain

    Full Text Available The performance of Watson & Ahumada's model of human visual motion sensing is compared against human psychophysical performance. The stimulus consists of random dots undergoing rotary motion, displayed in a circular annulus. The model matches psychophysical observer performance with respect to most parameters. It is able to replicate some key psychophysical findings such as invariance of observer performance to dot density in the display, and decrease of observer performance with frame duration of the display.Associated with the concept of rotary motion is the notion of a center about which rotation occurs. One might think that for accurate estimation of rotary motion in the display, this center must be accurately known. A simple vector analysis reveals that this need not be the case. Numerical simulations confirm this result, and may explain the position invariance of MST(d cells. Position invariance is the experimental finding that rotary motion sensitive cells are insensitive to where in their receptive field rotation occurs.When all the dots in the display are randomly drawn from a uniform distribution, illusory rotary motion is perceived. This case was investigated by Rose & Blake previously, who termed the illusory rotary motion the omega effect. Two important experimental findings are reported concerning this effect. First, although the display of random dots evokes perception of rotary motion, the direction of motion perceived does not depend on what dot pattern is shown. Second, the time interval between spontaneous flips in perceived direction is lognormally distributed (mode approximately 2 s. These findings suggest the omega effect fits in the category of a typical bistable illusion, and therefore the processes that give rise to this illusion may be the same processes that underlie much of other bistable phenomenon.

  13. Neural Network modeling of forward and inverse behavior of rotary MR damper

    DEFF Research Database (Denmark)

    Bhowmik, Subrata; Høgsberg, Jan Becker; Weber, Felix

    2010-01-01

    of nonlinear problems. The present paper concerns the nonparametric neural network modeling of the dynamic behavior of a rotary MR damper. A rotary type MR damper consists of a rotating disk which is enclosed in a metallic housing filled with the MR fluid which is operated in shear mode. The dissipative torque...

  14. Evaluation of Alternative Filter Media for the Rotary Microfilter

    Energy Technology Data Exchange (ETDEWEB)

    Poirier, M. R.; Herman, D. T.; Bhave, R.

    2011-11-09

    The Savannah River Site is currently developing and testing several processes to treat high level radioactive liquid waste. Each of these processes has a solid-liquid separation process that limits its throughput. Savannah River National Laboratory researchers identified and tested the rotary microfilter as a technology to increase solid-liquid separation throughput. The authors believe the rotary microfilter throughput can be improved by using a better filter membrane. Previous testing showed that asymmetric filters composed of a ceramic membrane on top of a stainless steel support produced higher filter flux than 100% stainless steel symmetric filters in crossflow filter tests. Savannah River National Laboratory and Oak Ridge National Laboratory are working together to develop asymmetric ceramic ? stainless steel composite filters and asymmetric 100% stainless steel filters to improve the throughput of the rotary microfilter. The Oak Ridge National Laboratory Inorganic Membrane Group fabricated samples of alternative filter membranes. In addition, Savannah River National Laboratory obtained samples of filter membranes from Pall, Porvair, and SpinTek. They tested these samples in a static test cell with feed slurries containing monosodium titanate and simulated sludge.

  15. Study of advanced rotary combustion engines for commuter aircraft

    Science.gov (United States)

    Berkowitz, M.; Jones, C.; Myers, D.

    1983-01-01

    Performance, weight, size, and maintenance data for advanced rotary aircraft engines suitable for comparative commuter aircraft system evaluation studies of alternate engine candidates are provided. These are turbocharged, turbocompounded, direct injected, stratified charge rotary engines. Hypothetical engines were defined (an RC4-74 at 895 kW and an RC6-87 at 1490 kW) based on the technologies and design approaches used in the highly advanced engine of a study of advanced general aviation rotary engines. The data covers the size range of shaft power from 597 kW (800 hp) to 1865 kW (2500 hp) and is in the form of drawings, tables, curves and written text. These include data on internal geometry and configuration, installation information, turbocharging and turbocompounding arrangements, design features and technologies, engine cooling, fuels, scaling for weight size BSFC and heat rejection for varying horsepower, engine operating and performance data, and TBO and maintenance requirements. The basic combustion system was developed and demonstrated; however the projected power densities and performance efficiencies require increases in engine internal pressures, thermal loading, and rotative speed.

  16. Evaluation of Alternative Filter Media for the Rotary Microfilter

    International Nuclear Information System (INIS)

    Poirier, M. R.; Herman, D. T.; Bhave, R.

    2011-01-01

    The Savannah River Site is currently developing and testing several processes to treat high level radioactive liquid waste. Each of these processes has a solid-liquid separation process that limits its throughput. Savannah River National Laboratory researchers identified and tested the rotary microfilter as a technology to increase solid-liquid separation throughput. The authors believe the rotary microfilter throughput can be improved by using a better filter membrane. Previous testing showed that asymmetric filters composed of a ceramic membrane on top of a stainless steel support produced higher filter flux than 100% stainless steel symmetric filters in crossflow filter tests. Savannah River National Laboratory and Oak Ridge National Laboratory are working together to develop asymmetric ceramic-stainless steel composite filters and asymmetric 100% stainless steel filters to improve the throughput of the rotary microfilter. The Oak Ridge National Laboratory Inorganic Membrane Group fabricated samples of alternative filter membranes. In addition, Savannah River National Laboratory obtained samples of filter membranes from Pall, Porvair, and SpinTek. They tested these samples in a static test cell with feed slurries containing monosodium titanate and simulated sludge

  17. The machined surface of magnesium AZ31 after rotary turning at air cooling condition

    Science.gov (United States)

    Akhyar, G.; Purnomo, B.; Hamni, A.; Harun, S.; Burhanuddin, Y.

    2018-04-01

    Magnesium is a lightweight metal that is widely used as an alternative to iron and steel. Magnesium has been applied in the automotive industry to reduce the weight of a component, but the machining process has the disadvantage that magnesium is highly flammable because it has a low flash point. High temperature can cause the cutting tool wear and contributes to the quality of the surface roughness. The purpose of this study is to obtain the value of surface roughness and implement methods of rotary cutting tool and air cooling output vortex tube cooler to minimize the surface roughness values. Machining parameters that is turning using rotary cutting tool at speed the workpiece of (Vw) 50, 120, 160 m/min, cutting speed of rotary tool of (Vt) 25, 50, 75 m/min, feed rate of (f) 0.1, 0.15, 0.2 mm/rev, and depth of cut of 0.3 mm. Type of tool used is a carbide tool diameter of 16 mm and air cooling pressure of 6 bar. The results show the average value of the lowest surface roughness on the speed the workpiece of 80 m/min, cutting speed of rotary tool of 50 m/min, feed rate of 0.2 mm/rev, and depth of cut of 0.3 mm. While the average value of the highest surface roughness on the speed the workpiece of 160 m/min, cutting speed of rotary tool of 50 m/min, feed rate of 0.2 mm/rev, and depth of cut of 0.3 mm. The influence of machining parameters concluded the higher the speed of the workpiece the surface roughness value higher. Otherwise the higher cutting speed of rotary tool then the lower the surface roughness value. The observation on the surface of the rotary tool, it was found that no uniform tool wear which causes non-uniform surface roughness. The use of rotary cutting tool contributing to lower surface roughness values generated.

  18. Stratified charge rotary aircraft engine technology enablement program

    Science.gov (United States)

    Badgley, P. R.; Irion, C. E.; Myers, D. M.

    1985-01-01

    The multifuel stratified charge rotary engine is discussed. A single rotor, 0.7L/40 cu in displacement, research rig engine was tested. The research rig engine was designed for operation at high speeds and pressures, combustion chamber peak pressure providing margin for speed and load excursions above the design requirement for a high is advanced aircraft engine. It is indicated that the single rotor research rig engine is capable of meeting the established design requirements of 120 kW, 8,000 RPM, 1,379 KPA BMEP. The research rig engine, when fully developed, will be a valuable tool for investigating, advanced and highly advanced technology components, and provide an understanding of the stratified charge rotary engine combustion process.

  19. Rotary core drills

    Energy Technology Data Exchange (ETDEWEB)

    1967-11-30

    The design of a rotary core drill is described. Primary consideration is given to the following component parts of the drill: the inner and outer tube, the core bit, an adapter, and the core lifter. The adapter has the form of a downward-converging sleeve and is mounted to the lower end of the inner tube. The lifter, extending from the adapter, is split along each side so that it can be held open to permit movement of a core. It is possible to grip a core by allowing the lifter to assume a closed position.

  20. Exergy analysis on the irreversibility of rotary air preheater in thermal power plant

    International Nuclear Information System (INIS)

    Wang Hongyue; Zhao Lingling; Zhou Qiangtai; Xu Zhigao; Kim, Hyung Taek

    2008-01-01

    Energy recovery devices can have a substantial impact on process efficiency and their relevance to the problem of conservation of energy resources is generally recognized to be beyond dispute. One type of such a device, which is commonly used in thermal power plants and air conditioning systems, is the rotary air preheater. A major disadvantage of the rotary air preheater is that there is an unavoidable leakage due to carry over and pressure difference. There are gas streams involved in the heat transfer and mixing processes. There are also irreversibilities, or exergy destruction, due to mixing, pressure losses and temperature gradients. Therefore, the purpose of this research paper is based from the second law of thermodynamics, which is to build up the relationship between the efficiency of the thermal power plant and the total process of irreversibility in the rotary air preheater using exergy analysis. For this, the effects of the variation of the principal design parameters on the rotary air preheater efficiency, the exergy efficiency, and the efficiency of the thermal power plant are examined by changing a number of parameters of rotary air preheater. Furthermore, some conclusions are reached and recommendations are made so as to give insight on designing some optimal parameters

  1. Numerical Analysis on Combustion Characteristic of Leaf Spring Rotary Engine

    Directory of Open Access Journals (Sweden)

    Yan Zhang

    2015-08-01

    Full Text Available The purpose of this paper is to investigate combustion characteristics for rotary engine via numerical studies. A 3D numerical model was developed to study the influence of several operative parameters on combustion characteristics. A novel rotary engine called, “Leaf Spring Rotary Engine”, was used to illustrate the structure and principle of the engine. The aims are to (1 improve the understanding of combustion process, and (2 quantify the influence of rotational speed, excess air ratio, initial pressure and temperature on combustion characteristics. The chamber space changed with crankshaft rotation. Due to the complexity of chamber volume, an equivalent modeling method was presented to simulate the chamber space variation. The numerical simulations were performed by solving the incompressible, multiphase Unsteady Reynolds-Averaged Navier–Stokes Equations via the commercial code FLUENT using a transport equation-based combustion model; a realizable  turbulence model and finite-rate/eddy-dissipation model were used to account for the effect of local factors on the combustion characteristics.

  2. Incidence of dentinal defects after root canal preparation: reciprocating versus rotary instrumentation.

    Science.gov (United States)

    Bürklein, Sebastian; Tsotsis, Polymnia; Schäfer, Edgar

    2013-04-01

    The purpose of this study was to evaluate the incidence of dentinal defects after root canal preparation with reciprocating instruments (Reciproc and WaveOne) and rotary instruments. One hundred human central mandibular incisors were randomly assigned to 5 groups (n = 20 teeth per group). The root canals were instrumented by using the reciprocating single-file systems Reciproc and WaveOne and the full-sequence rotary Mtwo and ProTaper instruments. One group was left unprepared as control. Roots were sectioned horizontally at 3, 6, and 9 mm from the apex and evaluated under a microscope by using 25-fold magnification. The presence of dentinal defects (complete/incomplete cracks and craze lines) was noted and analyzed by using the chi-square test. No defects were observed in the controls. All canal preparation created dentinal defects. Overall, instrumentation with Reciproc was associated with more complete cracks than the full-sequence files (P = .021). Although both reciprocating files produced more incomplete cracks apically (3 mm) compared with the rotary files (P = .001), no statistically significant differences were obtained concerning the summarized values of all cross sections (P > .05). Under the conditions of this study, root canal preparation with both rotary and reciprocating instruments resulted in dentinal defects. At the apical level of the canals, reciprocating files produced significantly more incomplete dentinal cracks than full-sequence rotary systems (P < .05). Copyright © 2013 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  3. Component Energy Efficiencies in a Novel Linear to Rotary Motion Inter-conversion Hydro-mechanism Running a Solar Tracker

    Directory of Open Access Journals (Sweden)

    Kant Eliab Kanyarusoke

    2018-01-01

    Full Text Available A new mechanism interconverting linear and rotary motion was investigated for energy transfers among its components. It employed a gear-rack set, a Hooke coupling and a specially designed bladder-valve system that regulated the motion. The purpose was to estimate individual component mechanical efficiencies as they existed in the prototype so that future reengineering of the mechanism could be properly targeted. Theoretical modelling of the mechanism was first done to obtain equations for efficiencies of the key components. Two-stage experimentation followed when running a solar tracker. The first stage produced data for inputting into the model to determine the efficiencies’ theoretical variation with the Hooke coupling shaft angle. The second one verified results of the Engineering Equation Solver (EES software solutions of the model. It was found that the energy transfer to focus on was that between the Hooke coupling and the output shaft because its efficiency was below 4%

  4. Rotary wave-ejector enhanced pulse detonation engine

    Science.gov (United States)

    Nalim, M. R.; Izzy, Z. A.; Akbari, P.

    2012-01-01

    The use of a non-steady ejector based on wave rotor technology is modeled for pulse detonation engine performance improvement and for compatibility with turbomachinery components in hybrid propulsion systems. The rotary wave ejector device integrates a pulse detonation process with an efficient momentum transfer process in specially shaped channels of a single wave-rotor component. In this paper, a quasi-one-dimensional numerical model is developed to help design the basic geometry and operating parameters of the device. The unsteady combustion and flow processes are simulated and compared with a baseline PDE without ejector enhancement. A preliminary performance assessment is presented for the wave ejector configuration, considering the effect of key geometric parameters, which are selected for high specific impulse. It is shown that the rotary wave ejector concept has significant potential for thrust augmentation relative to a basic pulse detonation engine.

  5. Cyclic Fatigue Resistance of 3 Proprietary Rotary File Brands and their Analogous EdgeEndo Counterparts.

    Science.gov (United States)

    2018-04-26

    Resistance of 3 Proprietary Rotary File Brands and their Analogous EdgeEndo Counterparts. 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) Sd...Endodontics 14. ABSTRACT Cyclic Fatigue Resistance of 3 Proprietary Rotary File Brands and their Analogous EdgeEndo Counterparts. David J. Weyh DDS...Resistance of 3 Proprietary Rotary File Brands and their Analogous EdgeEndo Counterparts. David J. Weyh DDS Jarom J. Ray DDS Introduction: The aim of this

  6. Mechanical and Metallurgical Properties of Various Nickel-Titanium Rotary Instruments

    OpenAIRE

    Shim, Kyu-Sang; Oh, Soram; Kum, KeeYeon; Kim, Yu-Chan; Jee, Kwang-Koo; Chang, Seok Woo

    2017-01-01

    The aim of this study was to investigate the effect of thermomechanical treatment on mechanical and metallurgical properties of nickel-titanium (NiTi) rotary instruments. Eight kinds of NiTi rotary instruments with sizes of ISO #25 were selected: ProFile, K3, and One Shape for the conventional alloy; ProTaper NEXT, Reciproc, and WaveOne for the M-wire alloy; HyFlex CM for the controlled memory- (CM-) wire; and TF for the R-phase alloy. Torsional fracture and cyclic fatigue fracture tests were...

  7. Multi-functional hinge equipped with a magneto-rheological rotary damper for solar array deployment system

    Science.gov (United States)

    Wen, Mingfu; Yu, Miao; Fu, Jie; Wu, Zhengzhong

    2015-02-01

    This article describes the design and simulation of a novel multi-functional hinge equipped with a rotary magnetorheological damper for solar array deployment system, which is comprised of a hinge, an angular sensor, a positioning and locking mechanism and a rotary damper. In order to achieve the compact design in structure, some components were reused in different function modules. It's the first to use magnet-rheological fluid (MRF) to dissipate the energy in solar array deployment system. The main advantage in using MR rotary damper instead of a viscous fluid rotary damper is that the damping force of MR damper can be adjusted according to the external magnetic field environment excited. A mechanic model was built and the structure design was focused on the MR rotary damper, a damping force model of this damper is deduced based on hydromechanics with Bingham plastic constitutive model. A simulation of deployment motion was taken to validate the motion sequence of various components during the unfolding and locking process. It can be obtained that a constant damping coefficient can hardly balance the different performance of solar deployment system, then a simulation of the proposed deployment system equipped with rotary MR damper was carried out. According to the simulation, it can be obtained that the terminal velocity decreased by 75.81% and the deployment time decreased by 72.37% compared with a given constant damping coefficients. Therefore, the proposed new type of rotary damper can reach a compromise with different performance utilizing an on-off control strategy.

  8. Gasoline New Timing and Flux Adjustable Rotary Valve Design (Hereinafter: Rotary Valve

    Directory of Open Access Journals (Sweden)

    Du huiqi

    2016-01-01

    Full Text Available Conventional gasoline engine with an umbrella valve control cylinder intake and exhaust, in order to achieve sealing effect, the valve is driven by the spring force; at the same time, when the cam opens the valve to overcome the spring force acting. Sealing the better, the more power consumed in the engine mechanical losses, the valve mechanism consumes about 30%, which is not a small loss! This article describes a new type of rotary valve is to significantly reduce mechanical losses, so as to achieve energy saving purposes.

  9. Lignite chemical conversion in an indirect heat rotary kiln gasifier

    Directory of Open Access Journals (Sweden)

    Hatzilyberis Kostas S.

    2006-01-01

    Full Text Available The results on the gasification of Greek lignite using two indirect heat (allothermal pilot rotary kiln gasifiers are reported in the present work. The development of this new reactor-gasifier concept intended for solid fuels chemical conversion exploits data and experience gained from the following two pilot plants. The first unit A (about 100 kg/h raw lignite demonstrated the production of a medium heating value gas (12-13 MJ/Nm3 with quite high DAF (dry ash free coal conversions, in an indirect heat rotary gasifier under mild temperature and pressure conditions. The second unit B is a small pilot size unit (about 10 kg/h raw lignite comprises an electrically heated rotary kiln, is an operation flexible and exhibits effective phase mixing and enhanced heat transfer characteristics. Greek lignite pyrolysis and gasification data were produced from experiments performed with pilot plant B and the results are compared with those of a theoretical model. The model assumes a scheme of three consecutive-partly parallel processes (i. e. drying, pyrolysis, and gasification and predicts DAF lignite conversion and gas composition in relatively good agreement with the pertinent experimental data typical of the rotary kiln gasifier performance. Pilot plant B is currently being employed in lime-enhanced gasification studies aiming at the production of hydrogen enriched synthesis gas. Presented herein are two typical gas compositions obtain from lignite gasification runs in the presence or not of lime. .

  10. TESTING OF A ROTARY MICROFILTER TO SUPPORT HANFORD APPLICATIONS

    International Nuclear Information System (INIS)

    Poirier, M; David Herman, D; David Stefanko, D; Samuel Fink, S

    2008-01-01

    Savannah River National Laboratory (SRNL) researchers are investigating and developing a rotary microfilter for solid-liquid separation applications at the Savannah River Site (SRS). Because of the success of that work, the Hanford Site is evaluating the use of the rotary microfilter for its Supplemental Pretreatment process. The authors performed rotary filter testing with a full-scale, 25-disk unit with 0.5 (micro) filter media manufactured by Pall Corporation using a Hanford AN-105 simulant at solids loadings of 0.06, 0.29, and 1.29 wt%. The conclusions from this testing are: (1) The filter flux at 0.06 wt% solids reached a near constant value at an average of 0.26 gpm/ft 2 (6.25 gpm total). (2) The filter flux at 0.29 wt% solids reached a near constant value at an average of 0.17 gpm/ft 2 (4 gpm total). (3) The filter flux at 1.29 wt% solids reached a near constant value at an average of 0.10 gpm/ft 2 (2.4 gpm total). (4) Because of differences in solids loadings, a direct comparison between crossflow filter flux and rotary filter flux is not possible. The data show the rotary filter produces a higher flux than the crossflow filter, but the improvement is not as large as seen in previous testing. (5) Filtrate turbidity measured < 4 NTU in all samples collected. (6) During production, the filter should be rinsed with filtrate or dilute caustic and drained prior to an extended shutdown to prevent the formation of a layer of settled solids on top of the filter disks. (7) Inspection of the seal faces after ∼ 140 hours of operation showed an expected amount of initial wear, no passing of process fluid through the seal faces, and very little change in the air channeling grooves on the stationary face. (8) Some polishing was observed at the bottom of the shaft bushing. The authors recommend improving the shaft bushing by holding it in place with a locking ring and incorporated grooves to provide additional cooling. (9) The authors recommend that CH2MHill Hanford

  11. Electrical signal transfer system for a rotary kiln

    International Nuclear Information System (INIS)

    Tyson, J.H.; Kennett, L.P.; Davidson, I.S.

    1985-01-01

    A rotary kiln has a number of thermocouples respectively sensing the kiln temperature at spaced locations and respectively connected to annular slip rings. Laterally facing peripheral surfaces of the rings are respectively cooperable with brush contacts connected to a bar and a fork which embraces a ring moveable axially with the rings. Thus on longitudinal expansion of the kiln the contacts are caused to move with the rings. The electric signals from the thermocouples are thus fed to stationary monitoring equipment. In a modification the ring sections are electrically isolated and each section is connected to a respective sensor. Position sensors may be used to detect the rotary position of the kiln. The invention can be applied to other sensors. (author)

  12. The modal density of composite beams incorporating the effects of shear deformation and rotary inertia

    Science.gov (United States)

    Bachoo, Richard; Bridge, Jacqueline

    2018-06-01

    Engineers and designers are often faced with the task of selecting materials that minimizes structural weight whilst meeting the required strength and stiffness. In many cases fibre reinforced composites (FRCs) are the materials of choice since they possess a combination of high strength and low density. Depending on the application, composites are frequently constructed to form long slender beam-like structures or flat thin plate-like structures. Such structures when subjected to random excitation have the potential to excite higher order vibratory modes which can contribute significantly to structure-borne sound. Statistical Energy Analysis (SEA) is a framework for modeling the high frequency vibration of structures. The modal density, which is typically defined as the number of modes per unit Hertz in a frequency band, is a fundamental parameter when applying SEA. This study derives formulas for the modal density of a fibre reinforced composite beam coupled in bending and torsion. The effects of shear deformation and rotary inertia are accounted for in the formulation. The modal density is shown to be insensitive to boundary conditions. Numerical analyses were carried out to investigate the variation of modal density with fibre orientation including and excluding the effects of shear deformation and rotary inertia. It was observed that neglecting such effects leads to underestimating the mode count in a particular frequency band. In each frequency band there exists a fibre orientation for which the modal density is minimized. This angular orientation is shown to be dependent on the shear rigidity as well as the bending, torsional and coupling rigidities. The foregoing observation becomes more pronounced with increasing frequency. The paper also addresses the modal density beyond the wave-mode transition frequency where the beam supports three propagating waves.

  13. Apically extruded debris with reciprocating single-file and full-sequence rotary instrumentation systems.

    Science.gov (United States)

    Bürklein, Sebastian; Schäfer, Edgar

    2012-06-01

    The purpose of this in vitro study was to assess the amount of apically extruded debris using rotary and reciprocating nickel-titanium instrumentation systems. Eighty human mandibular central incisors were randomly assigned to 4 groups (n = 20 teeth per group). The root canals were instrumented according to the manufacturers' instructions using the 2 reciprocating single-file systems Reciproc (VDW, Munich, Germany) and WaveOne (Dentsply Maillefer, Ballaigues, Switzerland) and the 2 full-sequence rotary Mtwo (VDW, Munich, Germany) and ProTaper (Dentsply Maillefer, Ballaigues, Switzerland) instruments. Bidistilled water was used as irrigant. The apically extruded debris was collected in preweighted glass vials using the Myers and Montgomery method. After drying, the mean weight of debris was assessed with a microbalance and statistically analyzed using analysis of variance and the post hoc Student-Newman-Keuls test. The time required to prepare the canals with the different instruments was also recorded. The reciprocating files produced significantly more debris compared with both rotary systems (P rotary instruments (P > .05), the reciprocating single-file system Reciproc produced significantly more debris compared with all other instruments (P Instrumentation was significantly faster using Reciproc than with all other instrument (P rotary instrumentation was associated with less debris extrusion compared with the use of reciprocating single-file systems. Copyright © 2012 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  14. Development of a natural gas stratified charge rotary engine

    Energy Technology Data Exchange (ETDEWEB)

    Sierens, R.; Verdonck, W.

    1985-01-01

    A water model has been used to determine the positions of separate inlet ports for a natural gas, stratified charge rotary engine. The flow inside the combustion chamber (mainly during the induction period) has been registered by a film camera. From these tests the best locations of the inlet ports have been obtained, a prototype of this engine has been built by Audi NSU and tested in the laboratories of the university of Gent. The results of these tests, for different stratification configurations, are given. These results are comparable with the best results obtained by Audi NSU for a homogeneous natural gas rotary engine.

  15. Features of rotary pump diagnostics without dismantling

    Directory of Open Access Journals (Sweden)

    Sergeev K. О.

    2017-12-01

    Full Text Available In ship power plants, rotor pumps have become very popular providing the transfer of various viscous fluids: fuels, oils, etc. Like all ship's mechanisms, pumps need proper maintenance and monitoring of technical condition. The most expedient is maintenance and repair carried out according to the results of dismantling diagnosis. The methods of vibrodiagnostics are mostly widespread for the diagnosis of pumps. Vibrodiagnosis of rotary pumps has a number of features due to the nature and condition of pumped fluids. The norms of the Russian Maritime Register of Shipping are used for setting standards of vibration and diagnostics of the rotary pumps' technical condition. To clarify the features of vibration diagnostics of rotary pumps some measurements have been made on a special bench that simulates various modes of ship's pumps' operation: different pressure in the system and temperature of the pumped medium. As a result of measurements one-third octave and narrow-band vibration spectra of pumps have been obtained at various developed pressures and temperatures of the pumped fluid. The performed analysis has shown that the RMRS norms for diagnostics of ship rotary pumps have insufficient informative value inasmuch they do not take into account the dependence of the vibrational signal spectrum on the developed pressure and temperature of the pumped fluid. The nature of the received signals shows that the levels of a third-octave spectrum of the vibration velocity depend significantly on the temperature of the pumped fluids, this fact must be taken into account when applying the RMRS norms. The fluid temperature has a great influence on the nature of the narrow-band vibration acceleration spectrum in the area of medium frequencies, less influence – on the nature of the vibration velocity spectrum. The conclusions have been drawn about the advisability of using the narrow-band vibration spectra and the envelope spectra of the high

  16. A numerical study on the influence of gas-liquid two phase flow on the rotary pump performances

    International Nuclear Information System (INIS)

    Miao, T C; Liu, Y Y; Zhao, F; Wang, L Q

    2013-01-01

    Rotary pump can be used in many fields because of its strong self-priming ability. Many factors may cause the medium in rotary pump system containing gas-liquid two phase. And the suction capacity of rotary pump will decrease sharply in these situations. To study the internal flow mechanism of rotary pump when transporting medium containing gas, the gas-liquid two phase flow in the rotary pump system has been simulated using VOF model under different gas fractions. And the interaction between rotary pump and the pipeline has been considered. The simulation results coincide well with the theoretical calculation results, and the distribution of the flow field match well with the Mandhane flow pattern map. The main conclusions are as follows: with the increase of gas fraction, the flow pattern in the pipeline has the following evolutionary trend (bubble – plug – slug – wavy), and the suction capacity of the pump will decrease. It is mainly because gas medium can fill the partial vacuum produced by the rotor motion easily and is easier to have backflow

  17. Numerical Modeling of Rotary Kiln Productivity Increase

    NARCIS (Netherlands)

    Romero-Valle, M.A.; Pisaroni, M.; Van Puyvelde, D.; Lahaye, D.J.P.; Sadi, R.

    2013-01-01

    Rotary kilns are used in many industrial processes ranging from cement manufacturing to waste incineration. The operating conditions vary widely depending on the process. While there are many models available within the literature and industry, the wide range of operating conditions justifies

  18. Ultrafast Dynamics in Light-Driven Molecular Rotary Motors Probed by Femtosecond Stimulated Raman Spectroscopy

    NARCIS (Netherlands)

    Hall, Christopher R.; Conyard, Jamie; Heisler, Ismael A.; Jones, Garth; Frost, James; Browne, Wesley R.; Feringa, Ben L.; Meech, Stephen R.

    2017-01-01

    Photochemical isomerization in sterically crowded chiral alkenes is the driving force for molecular rotary motors in nanoscale machines. Here the excited-state dynamics and structural evolution of the prototypical light-driven rotary motor are followed on the ultrafast time scale by femtosecond

  19. Torque controlled rotary-shear experiments reveal pseudotachilites formation-dynamics and precursor events

    Science.gov (United States)

    Tisato, Nicola; Cordonnier, Benoit; De Siena, Luca; Lavier, Luc; Di Toro, Giulio

    2017-04-01

    Except few cases, rotary shear tests, which are designed to study dynamic friction and strengthening/weakening mechanisms in seismogenic faults, are performed by imposing, to the specimens, a slipping velocity that is pre-defined. This approach has been adopted from engineering that typically, tests man-made objects that, when functioning, spin or slide at a pre-defined velocity under a pre-defined load. On the other hand, natural earthquakes are the effect of a rupture that nucleates, propagates and arrests in the subsurface. These three phases, and the consequent emerging fault slipping velocity, are controlled by the accumulated and released energy around the seismogenic fault before, during and after the earthquake. Thus, imposing the slipping velocity in laboratory experiments might not represent the best option to uncover many aspects of earthquake nucleation and fault slipping dynamics. Here we present some experiments performed with an innovative rotary shear apparatus that uses a clock-spring that when winded provides to the rotating sample a linearly increasing torque. Thus, the nucleation of simulated events occur spontaneously when the shear stress on the slipping surface overcomes the static friction times the normal load that is controlled by a deadweight. In addition, this method allows studying precursory seismic events resembling natural slow-slip earthquakes. We report some preliminary results for a transparent polymer that has melting point 340 K and allows observing the slipping surface (i.e., the contact between the two samples). By coupling: i) the rotary shear apparatus, ii) a video camera recording at 60 fps and a iii) laser pointer we observed the formation and evolution of a melt film that forms in the slipping surface after a phase of "dry" stick-slip. After each seismic event the melt layer solidify forming a pseudotachilite that partially welds the slipping surfaces. We also present the mechanical data that show rupture strengthening in

  20. Modeling of Installations with a Rotary Kiln for Thermal Decontamination of Wastes

    Directory of Open Access Journals (Sweden)

    Krot O.P.

    2018-04-01

    Full Text Available The object of the study is a plant for incineration of solid wastes in a rotary kiln with an afterburning chamber and thermal catalytic emission purification. The aim of the study was to determine the rational layout of the solid wastes loading system and the location of the burner during combustion in the system - a rotary kiln and an afterburning chamber. The results of simulation countercurrent and concurrent gas flow and wastes in the form of temperature gradients in the rotary kiln and afterburner chamber are presented. It is found that in the initial part of the rotary kiln, a temperature of more than 1000 °C is created on its lower surface, almost one-third of the length of the furnace (2.5-3 times more than in the concurrent mode. In a zone close to unloading, the temperature is minimal (less than 100 °C, therefore, the slag does not tolerate heat from the furnace, it has time to cool down. Criteria for the efficiency of the rotary kiln have been proposed: the length of the section where the maximum combustion temperature is reached, the length of the section before discharge of the slag, the temperature of the slag. A more efficient configuration for all the criteria is one that ensures the counter movement of debris and gas. To effectively use the volume of the afterburner chamber, the burners must be located at the maximum distance from each other. The outlet flue must also be as far from the burners as possible.

  1. Development of natural gas rotary engines

    Science.gov (United States)

    Mack, J. R.

    1991-08-01

    Development of natural gas-fueled rotary engines was pursued on the parallel paths of converted Mazda automotive engines and of establishing technology and demonstration of a test model of a larger John Deer Technologies Incorporated (JDTI) rotary engine with power capability of 250 HP per power section for future production of multi-rotor engines with power ratings 250, 500, and 1000 HP and upward. Mazda engines were converted to natural gas and were characterized by a laboratory which was followed by nearly 12,000 hours of testing in three different field installations. To develop technology for the larger JDTI engine, laboratory and engine materials testing was accomplished. Extensive combustion analysis computer codes were modified, verified, and utilized to predict engine performance, to guide parameters for actual engine design, and to identify further improvements. A single rotor test engine of 5.8 liter displacement was designed for natural gas operation based on the JDTI 580 engine series. This engine was built and tested. It ran well and essentially achieved predicted performance. Lean combustion and low NOW emission were demonstrated.

  2. Pneumatic Rotary Actuator Position Servo System Based on ADE-PD Control

    Directory of Open Access Journals (Sweden)

    Yeming Zhang

    2018-03-01

    Full Text Available In order to accurately control the rotation position of a pneumatic rotary actuator, the flow state of the gas and the motion state of the pneumatic rotary actuator in the pneumatic rotary actuator position servo system are analyzed in this paper. The mathematical model of the system and the experiment platform are established after that. An Adaptive Differential Evolution (ADE algorithm which adaptively ameliorates the scaling factor and crossover probability in the process of individual evolution is proposed and applied to the parameter optimization of PD controller. The experimental platform is used to compare the controller with Differential Evolution (DE algorithm and NCD-PID controller. Finally, the characteristics of the system are tested by increasing the inertial load. The experimental results illustrate that system using ADE-PD control strategy has greater position precision and faster response than using DE-PD and NCD-PID strategies, and shows great robustness.

  3. Advanced liquid-cooled, turbocharged and intercooled stratified charge rotary engines for aircraft

    Science.gov (United States)

    Mount, Robert E.; Bartel, John; Hady, William F.

    1987-01-01

    Developments concerning stratified-charge rotary (SCR) engines over the past 10 years are reviewed. Aircraft engines being developed using SCR technology are shown and described, and the ability of such technology to meet general aviation engine needs is considered. Production timing and availability of SCR technology for the development of aviation rotary engines are discussed, and continuing efforts toward improving this technology, including NASA efforts, are described.

  4. A reduced fidelity model for the rotary chemical looping combustion reactor

    International Nuclear Information System (INIS)

    Iloeje, Chukwunwike O.; Zhao, Zhenlong; Ghoniem, Ahmed F.

    2017-01-01

    Highlights: • Methodology for developing a reduced fidelity rotary CLC reactor model is presented. • The reduced model determines optimal reactor configuration that meets design and operating requirements. • A 4-order of magnitude reduction in computational cost is achieved with good prediction accuracy. • Sensitivity studies demonstrate importance of accurate kinetic parameters for reactor optimization. - Abstract: The rotary chemical looping combustion reactor has great potential for efficient integration with CO_2 capture-enabled energy conversion systems. In earlier studies, we described a one-dimensional rotary reactor model, and used it to demonstrate the feasibility of continuous reactor operation. Though this detailed model provides a high resolution representation of the rotary reactor performance, it is too computationally expensive for studies that require multiple model evaluations. Specifically, it is not ideal for system-level studies where the reactor is a single component in an energy conversion system. In this study, we present a reduced fidelity model (RFM) of the rotary reactor that reduces computational cost and determines an optimal combination of variables that satisfy reactor design requirements. Simulation results for copper, nickel and iron-based oxygen carriers show a four-order of magnitude reduction in simulation time, and reasonable prediction accuracy. Deviations from the detailed reference model predictions range from 3% to 20%, depending on oxygen carrier type and operating conditions. This study also demonstrates how the reduced model can be modified to deal with both optimization and design oriented problems. A parametric study using the reduced model is then applied to analyze the sensitivity of the optimal reactor design to changes in selected operating and kinetic parameters. These studies show that temperature and activation energy have a greater impact on optimal geometry than parameters like pressure or feed fuel

  5. Design analysis of rotary turret of poucher machine

    Directory of Open Access Journals (Sweden)

    Jigar G. Patel

    2016-09-01

    Full Text Available This paper present design analysis of rotary turret plate of 5 kg capacity for food product packaging machine. The turret plate has been designed considering two different criteria, first one is inertia force approach with only self-weight of turret plate and second is with mass of pouches. A 3-dimenssional CAD model of rotary turret assembly has been prepared in using solid modelling packages CRE-O. The finite element analysis (FEA of turret plate has been carried out using analysis software ANSYS 15.0. Consideration of inertia force is one of the criteria to analyze the performance and behaviour of component in working condition. The rotational velocity is applied at the central axis of turret and friction less support is applied on inner surface, where shaft is being attached. Also, pressure is applied on the same surface to incorporate the shrink fit condition of the assembly of turret plate with shaft. The boundary conditions as fixed support have been considered at the different sixteen faces, where bolts have been attached. The obtained simulation results for induced stress, deformation and strain depict that the modified design of rotary turret plate is well within the allowable stress limits of considered material. And, further optimization can be performed for topological and strength based more efficient design of turret plate.

  6. A novel redundant INS based on triple rotary inertial measurement units

    Science.gov (United States)

    Chen, Gang; Li, Kui; Wang, Wei; Li, Peng

    2016-10-01

    Accuracy and reliability are two key performances of inertial navigation system (INS). Rotation modulation (RM) can attenuate the bias of inertial sensors and make it possible for INS to achieve higher navigation accuracy with lower-class sensors. Therefore, the conflict between the accuracy and cost of INS can be eased. Traditional system redundancy and recently researched sensor redundancy are two primary means to improve the reliability of INS. However, how to make the best use of the redundant information from redundant sensors hasn’t been studied adequately, especially in rotational INS. This paper proposed a novel triple rotary unit strapdown inertial navigation system (TRUSINS), which combines RM and sensor redundancy design to enhance the accuracy and reliability of rotational INS. Each rotary unit independently rotates to modulate the errors of two gyros and two accelerometers. Three units can provide double sets of measurements along all three axes of body frame to constitute a couple of INSs which make TRUSINS redundant. Experiments and simulations based on a prototype which is made up of six fiber-optic gyros with drift stability of 0.05° h-1 show that TRUSINS can achieve positioning accuracy of about 0.256 n mile h-1, which is ten times better than that of a normal non-rotational INS with the same level inertial sensors. The theoretical analysis and the experimental results show that due to the advantage of the innovative structure, the designed fault detection and isolation (FDI) strategy can tolerate six sensor faults at most, and is proved to be effective and practical. Therefore, TRUSINS is particularly suitable and highly beneficial for the applications where high accuracy and high reliability is required.

  7. Glide path preparation in S-shaped canals with rotary pathfinding nickel-titanium instruments.

    Science.gov (United States)

    Ajuz, Natasha C C; Armada, Luciana; Gonçalves, Lucio S; Debelian, Gilberto; Siqueira, José F

    2013-04-01

    This study compared the incidence of deviation along S-shaped (double-curved) canals after glide path preparation with 2 nickel-titanium (NiTi) rotary pathfinding instruments and hand K-files. S-shaped canals from 60 training blocks were filled with ink, and preinstrumentation images were obtained by using a stereomicroscope. Glide path preparation was performed by an endodontist who used hand stainless steel K-files (up to size 20), rotary NiTi PathFile instruments (up to size 19), or rotary NiTi Scout RaCe instruments (up to size 20). Postinstrumentation images were taken by using exactly the same conditions as for the preinstrumentation images, and both pictures were superimposed. Differences along the S-shaped canal for the mesial and distal aspects were measured to evaluate the occurrence of deviation. Intragroup analysis showed that all instruments promoted some deviation in virtually all levels. Overall, regardless of the group, deviations were observed in the mesial wall at the canal terminus and at levels 4, 5, 6 and 7 mm and in the distal wall at levels 1, 2, and 3 mm. These levels corresponded to the inner walls of each curvature. Both rotary NiTi instruments performed significantly better than hand K-files at all levels (P instruments showed significantly better results than PathFiles at levels 0, 2, 3, 5, and 6 mm (P rotary NiTi instruments are suitable for adequate glide path preparation because they promoted less deviation from the original canal anatomy when compared with hand-operated instruments. Of the 2 rotary pathfinding instruments, Scout RaCe showed an overall significantly better performance. Copyright © 2013 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  8. Math modeling and computer mechanization for real time simulation of rotary-wing aircraft

    Science.gov (United States)

    Howe, R. M.

    1979-01-01

    Mathematical modeling and computer mechanization for real time simulation of rotary wing aircraft is discussed. Error analysis in the digital simulation of dynamic systems, such as rotary wing aircraft is described. The method for digital simulation of nonlinearities with discontinuities, such as exist in typical flight control systems and rotor blade hinges, is discussed.

  9. Design, development and performance of a disk plow combined with rotary blades

    International Nuclear Information System (INIS)

    Hashemi, A; Ahmad, D; Othman, J; Sulaiman, S

    2012-01-01

    Disk plow combined with rotary blades, defined as comboplow, is used for soil preparation for planting. The comboplow includes four units: Chassis, concave disk, transmission system and rotary blades. A multiple tillage operation is reduced in a single pass resulting in a potential reduction of soil compaction, labor, fuel cost and saving in time. The comboplow was tested at University Putra Malaysia Research Park, Serdang, Selangor, Malaysia, on three different plots of 675 m 2 in the year 2010/2011. The treatments were three types of blade [(straight (S),curved (c) and L-shaped)] and three rotary speeds (130,147and 165 rpm). The parameters were Mean Weight Diameter Dry Basis (MWD d ), Mean weight Diameter Wet Basis (MWD W ), Aggregate Stability Index (SI) and Instability Index (II).

  10. Decrease in Accuracy of a Rotational SINS Caused by its Rotary Table's Errors

    Directory of Open Access Journals (Sweden)

    Pin Lv

    2014-05-01

    Full Text Available We call a strapdown inertial navigation system (SINS that uses the rotation auto-compensation technique (which is a common method to reduce the effect of the bias errors of inertial components a ‘rotational SINS’. In a rotational SINS, the rotary table is an important component, rotating the inertial sensor assembly back and forth in azimuth to accomplish error modulation. As a consequence of the manufacturing process, errors may exist in rotary tables which decrease the navigation accuracy of rotational SINSs. In this study, the errors of rotary tables are considered in terms of installation error, wobble error and angular error, and the models of these errors are established for the rotational SINS. Next, the propagation characteristics of these errors in the rotational SINS are analysed and their effects on navigation results are discussed. Finally, the theoretical conclusions are tested by numerical simulation. This paper supplies a good reference for the development of low-cost rotational SINSs, which usually have low accuracy rotary tables and which may be used in robots, intelligent vehicles and unmanned aerial vehicles (UAVs.

  11. Rotary retort for carbonizing bituminous materials

    Energy Technology Data Exchange (ETDEWEB)

    Meguin, A G; Muller, W

    1920-09-05

    A process of carbonizing bituminous materials, such as coal and oil shale at a low temperature in a rotary retort with simultaneous compressing the material especially of the semicoke formed that is characterized in that the material during the distillation through rapid rotation of the retort is exposed to the action of centrifugal force and thereby it is compressed.

  12. Design and analysis of a rotary motion controller

    Directory of Open Access Journals (Sweden)

    Julio Cesar Caye

    2015-12-01

    Full Text Available This paper presents the design of a rotary motion controller based on the peritrochoid geometry of the rotary (Wankle engine. It uses an orifice limited flow of incompressible fluid between the chambers of the Wankle-type geometry to control the rotation of the rotor. The paper develops the theory of operation and then implements the design as a Matlab model to simulate the motion control under various conditions. It is found that the time to reach stabilised motion is determined by the orifice size and fluid density. When stabilised motion is achieved, the motion dependence on material and geometry factors is determined by the orifice flow equation. The angular velocity is also found to have a square root dependence on the applied torque when in the stabilised regime.

  13. Feeding device for rotary retorts

    Energy Technology Data Exchange (ETDEWEB)

    Hutchins, T W.S.

    1923-04-25

    A horizontal rotary retort is heated externally with a feeding-worm or the like for distilling coal, oil shale, etc. It is characterized in that the shaft of the feeder moves adjustably lengthwise, so that, under the hopper more or less of the worm comes for action on the feed, so that the hopper is withdrawn through the retort while it projects into the retort and is secured in a position against the rotation.

  14. Percussive Augmenter of Rotary Drills for Operating as a Rotary-Hammer Drill

    Science.gov (United States)

    Aldrich, Jack Barron (Inventor); Bar-Cohen, Yoseph (Inventor); Sherrit, Stewart (Inventor); Badescu, Mircea (Inventor); Bao, Xiaoqi (Inventor); Scott, James Samson (Inventor)

    2014-01-01

    A percussive augmenter bit includes a connection shaft for mounting the bit onto a rotary drill. In a first modality, an actuator percussively drives the bit, and an electric slip-ring provides power to the actuator while being rotated by the drill. Hammering action from the actuator and rotation from the drill are applied directly to material being drilled. In a second modality, a percussive augmenter includes an actuator that operates as a hammering mechanism that drives a free mass into the bit creating stress pulses that fracture material that is in contact with the bit.

  15. Sealing performance of a magnetic fluid seal for rotary blood pumps.

    Science.gov (United States)

    Mitamura, Yoshinori; Takahashi, Sayaka; Kano, Kentaro; Okamoto, Eiji; Murabayashi, Shun; Nishimura, Ikuya; Higuchi, Taka-Aki

    2009-09-01

    A magnetic fluid (MF) for a rotary blood pump seal enables mechanical contact-free rotation of the shaft and, hence, has excellent durability. The performance of a MF seal, however, has been reported to decrease in liquids. We have developed a MF seal that has a "shield" mechanism and a new MF with a higher magnetization of 47.9 kA/m. The sealing performance of the MF seal installed in a rotary blood pump was studied. Under the condition of continuous flow, the MF seal remained in perfect condition against a pressure of 298 mm Hg (pump flow rate: 3.96 L/min). The seal was also perfect against a pressure of 170 mm Hg in a continuous flow of 3.9 L/min for 275 days. We have developed a MF seal that works in liquid against clinically used pressures. The MF seal is promising as a shaft seal for rotary blood pumps.

  16. Precision Model for Microwave Rotary Vane Attenuator

    DEFF Research Database (Denmark)

    Guldbrandsen, Tom

    1979-01-01

    A model for a rotary vane attenuator is developed to describe the attenuator reflection and transmission coefficients in detail. All the parameters of the model can be measured in situ, i.e., without diassembling any part. The tranmission errors caused by internal reflections are calculated from ...

  17. High-speed rotary atherectomy under fluoroscopic and angioscopic guidance

    International Nuclear Information System (INIS)

    Deutsch, L.S.; Ahn, S.S.; Yeatman, L.A.; Marcus, D.R.; Auth, D.P.; Moore, W.S.

    1988-01-01

    This paper describes thirteen stenotic arteries treated by high-speed rotary abrasive burr atherectomy performed in the operating room under fluoroscopic-angioscopic control by a multidisciplinary team consisting of a vascular surgeon, an interventional radiologist, and an interventional cardiologist. Incrementally sized atherectomy burrs were used in each patient (1.75-4.0 mm in diameter). Rotary artherectomy was successful in 11 of 13 arteries ranging from 1 to 40 cm (median, 5 cm) with stenoses ranging from 50% to 99% (median, 90%), which improved to less than 30% in all 11 successfully atherectomized segments. Two early posttreatment failures (intimal dissection, burr shaft disruption), two posttreatment thromboses (unrelated to atherectomy), and two late failures (restenosis) occurred

  18. Analysis and test of insulated components for rotary engine

    Science.gov (United States)

    Badgley, Patrick R.; Doup, Douglas; Kamo, Roy

    1989-01-01

    The direct-injection stratified-charge (DISC) rotary engine, while attractive for aviation applications due to its light weight, multifuel capability, and potentially low fuel consumption, has until now required a bulky and heavy liquid-cooling system. NASA-Lewis has undertaken the development of a cooling system-obviating, thermodynamically superior adiabatic rotary engine employing state-of-the-art thermal barrier coatings to thermally insulate engine components. The thermal barrier coating material for the cast aluminum, stainless steel, and ductile cast iron components was plasma-sprayed zirconia. DISC engine tests indicate effective thermal barrier-based heat loss reduction, but call for superior coefficient-of-thermal-expansion matching of materials and better tribological properties in the coatings used.

  19. The effect of intermittent passive ultrasonic irrigation and rotary instruments on microbial colonies of infected root canals

    International Nuclear Information System (INIS)

    AlMadi, Ebtissam M; Balto, Hanan A

    2008-01-01

    To study the effectiveness of reduction of E. faecalis in root canals with passive ultrasonic irrigation (PUI) of 2.25% NaOCl for 1.5 min intermittently during hand instrumentation and continuously after rotary instrumentation. Forty-eight extracted single rooted teeth were filled with E. faecalis suspension and divided into 4 groups. They were either hand instrumented alone using the stepback technique, hand instrumented with PUI of the 2.25% NaOCl intermittently for a total of 1.5 min during the instrumentation, rotary instrumented with ProFile 0.04 alone, or rotary instrumented with PUI of the irrigant for 1.5 min. There was significantly more bacterial growth in the hand instrumented group than in the hand instrumented group with PUI, and marginal significant difference in the hand instrumented group with PUI compared to the rotary instrumented group. No differences were found between the rotary instrumented groups. It was concluded that intermittent use of PUI of 2.25% NaOCl for a total of 1.5 min (half of the current recommended time) during hand instrumentation reduced bacterial colonies significantly. There was no difference in bacterial reduction when rotary instrumentation was used with or without PUI. (author)

  20. Experimental Investigation of a Multi-Cycle Single-Tube Pulse Detonation Rocket Engine with a Coaxial Rotary Valve

    Science.gov (United States)

    Matsuoka, Ken; Esumi, Motoki; Ikeguchi, Ken Bryan; Kasahara, Jiro; Matsuo, Akiko; Funaki, Ikkoh

    We developed a novel coaxial rotary valve for a multi-tube PDE. Since this single valve can supply three different gases (fuel, oxidizer and purge gas) into a combustor, the unification of the valve systems for three different gases is possible by using our newly designed valve. A PDRE system can be simple and lightweight by using this valve, and thus its thrust-weight ratio can be increased. We proposed the design of a multi-tube rotary-valved PDRE system by this rotary valve. Moreover, in preparation for a multi-tube rotary-valved PDRE, we carried out the multi-cycle operation experiment by the single-tube rotary-valved PDRE system. The combustion wave velocity was measured to confirm the operation of the PDRE system. Deflagration-to-detonation transition (DDT) was confirmed and DDT distance decreased under the condition of high operation frequency. In addition, a maximum operation frequency was 159 Hz.

  1. Rotary klubi tuli rannarahvale appi / Anu Jürisson

    Index Scriptorium Estoniae

    Jürisson, Anu

    2005-01-01

    Tallinna Vanalinna Rotary klubi kinkis kolmele Rannametsa perele kümme tuhat krooni jaanuaritormi kahjustuste likvideerimiseks. Klubi presidendiks on Allan Martinson, nimekirjas ka Tõnis Palts, Toomas Hendrik Ilves, Rein Kilk, Hans H. Luik, Vahur Kraft jt.

  2. Fatigue behavior of lubricated Ni-Ti endodontic rotary instruments

    Directory of Open Access Journals (Sweden)

    A. Brotzu

    2014-04-01

    Full Text Available The use of Ni-Ti alloys in the practice of endodontic comes from their important properties such as shape memory and superelasticity phenomena, good corrosion resistance and high compatibility with biological tissues. In the last twenty years a great variety of nickel-titanium rotary instruments, with various sections and taper, have been developed and marketed. Although they have many advantages and despite their increasing popularity, a major concern with the use of Ni-Ti rotary instruments is the possibility of unexpected failure in use due to several reasons: novice operator handling, presence manufacturing defects, fatigue etc. Recently, the use of an aqueous gel during experimental tests showed a longer duration of the instruments. The aim of the present work is to contribute to the study of the fracture behavior of these endodontic rotary instruments particularly assessing whether the use of the aqueous lubricant gel can extend their operative life stating its reasons. A finite element model (FEM has been developed to support the experimental results. The results were rather contradictory, also because the Perspex (Poly-methyl methacrylate, PMMA cannot simulate completely the dentin mechanical behavior; however the results highlight some interesting points which are discussed in the paper.

  3. Rotary union for use with ultrasonic thickness measuring probe

    Science.gov (United States)

    Nachbar, Henry D.

    1992-01-01

    A rotary union for rotatably supporting an ultrasonic probe operable to nondestructively measure the thickness of steam generator tubes to determine the amount of corrosion experienced by the tubes includes a stationary body having a bore therethrough and an outlet drain, and a fitting rotatably mounted within the upper end of the body. The fitting has a bore aligned with the bore of the body. An electrical cable positioned within a water supply tube in an annular arrangement passes through the bore of the body and the bore of the fitting. This annular arrangement, in turn, is positioned within a connector element which extends outwardly from the fitting bore and is connected to the ultrasonic probe. An elastomeric lower bushing seals the annular arrangement to the lower end of the rotary union body and an elastomeric upper bushing seals the connector element to the fitting to permit the connector element and the ultrasonic probe connected thereto to rotate with the fitting relative to the body. The lower and upper bushings permit water to be passed through the annular arrangement and into the ultrasonic probe and thereafter discharged between the annular arrangement and the connector element to the outlet drain of the rotary union body.

  4. Rotary union for use with ultrasonic thickness measuring probe

    International Nuclear Information System (INIS)

    Nachbar, H.D.

    1992-01-01

    A rotary union for rotatably supporting an ultrasonic probe operable to nondestructively measure the thickness of steam generator tubes to determine the amount of corrosion experienced by the tubes includes a stationary body having a bore therethrough and an outlet drain, and a fitting rotatably mounted within the upper end of the body. The fitting has a bore aligned with the bore of the body. An electrical cable positioned within a water supply tube in an annular arrangement passes through the bore of the body and the bore of the fitting. This annular arrangement, in turn, is positioned within a connector element which extends outwardly from the fitting bore and is connected to the ultrasonic probe. An elastomeric lower bushing seals the annular arrangement to the lower end of the rotary union body and an elastomeric upper bushing seals the connector element to the fitting to permit the connector element and the ultrasonic probe connected thereto to rotate with the fitting relative to the body. The lower and upper bushings permit water to be passed through the annular arrangement and into the ultrasonic probe and thereafter discharged between the annular arrangement and the connector element to the outlet drain of the rotary union body. 5 figs

  5. Miniaturized Rotary Actuators Using Shape Memory Alloy for Insect-Type MEMS Microrobot

    Directory of Open Access Journals (Sweden)

    Ken Saito

    2016-03-01

    Full Text Available Although several types of locomotive microrobots have been developed, most of them have difficulty locomoting on uneven surfaces. Thus, we have been focused on microrobots that can locomote using step patterns. We are studying insect-type microrobot systems. The locomotion of the microrobot is generated by rotational movements of the shape memory alloy-type rotary actuator. In addition, we have constructed artificial neural networks by using analog integrated circuit (IC technology. The artificial neural networks can output the driving waveform without using software programs. The shape memory alloy-type rotary actuator and the artificial neural networks are constructed with silicon wafers; they can be integrated by using micro-electromechanical system (MEMS technology. As a result, the MEMS microrobot system can locomote using step patterns. The insect-type MEMS microrobot system is 0.079 g in weight and less than 5.0 mm in size, and its locomotion speed is 2 mm/min. The locomotion speed is slow because the heat of the shape memory alloy conducts to the mechanical parts of the MEMS microrobot. In this paper, we discuss a new rotary actuator compared with the previous model and show the continuous rotation of the proposed rotary actuator.

  6. Practical application of silicon nitride ceramics for sliding parts of rotary engine

    International Nuclear Information System (INIS)

    Ueki, M.; Sato, Y.; Fukuda, K.

    1994-01-01

    Research on ceramic substitutes for the apex seals of the rotary engine have been carrying out. The aim of the substitution of apex seals, the development of high strength silicon nitride ceramics, and the application of the ceramic to the apex seals are described. The properties of silicon nitride ceramics used as apex seals in rotary engines for racing cars are presented. The apex seals were recovered from the rotary engines of racing cars in the 1989 and 1990 Le Mans 24-hour Grand Prix races, and the damage of the seals was investigated and analyzed in detail. One problem was the adhesion to the seals of the hardened chromium plating detached from the inside surface of the rotor housing. The adhesion of chromium caused the fine cracking and subsequent chipping of the apex seals. (orig.)

  7. Strength and reversibility of stereotypes for a rotary control with linear scales.

    Science.gov (United States)

    Chan, Alan H S; Chan, W H

    2008-02-01

    Using real mechanical controls, this experiment studied strength and reversibility of direction-of-motion stereotypes and response times for a rotary control with horizontal and vertical scales. Thirty-eight engineering undergraduates (34 men and 4 women) ages 23 to 47 years (M=29.8, SD=7.7) took part in the experiment voluntarily. The effects of instruction of change of pointer position and control plane on movement compatibility were analyzed with precise quantitative measures of strength and a reversibility index of stereotype. Comparisons of the strength and reversibility values of these two configurations with those of rotary control-circular display, rotary control-digital counter, four-way lever-circular display, and four-way lever-digital counter were made. The results of this study provided significant implications for the industrial design of control panels for improved human performance.

  8. Comparative evaluation of fracture and defect in reciproc and rotary files in severe curved root canals

    Directory of Open Access Journals (Sweden)

    Mahdis Bagherian

    2015-03-01

    Full Text Available Introduction: Root canal instrumentation is an important phase in root canal therapy. Since success in endodontic treatment depends on file defect and fracture, the aim of this study was to compare the evaluation of defect and fracture in rotary and reciproc files in severe curved root canals. Materials & Methods: In this experimental study, 60 mesial canals of human closed apex molars with more than 30° canal curvature were randomly divided into two groups. In first group M-two rotary files number# 15, 20, and 25 and in second group R25 reciproc file were used for filing, respectively. A ×8 magnifier was applied to evaluate the defect or fracture presence in each side and if it were observed, a new file would be replaced. Therefore, the number of prepared canals with each file and fractured or defective files and the place of fracture in root canal were recorded. Kaplan Meier curve and log rank test were done by using SPSS v.22. Results: In rotary group, seven and two files were fractured and defected, respectively and four files were fractured and no defect was observed in reciproc group. Although the mean of the number of prepared canals until fracture or defect in rotary and reciproc groups was 3.3 and 7.06, respectively, there were no significant differences between two systems. All file’s fractures occurred in apical regions . Conclusion: The results showed that there was no significant difference in defects or fractures of rotary and reciproc systems. Reciproc instruments can be more effective than rotary ones because the root canal preparation in rotary instruments is longer than in reciproc system.

  9. A reduced fidelity model for the rotary chemical looping combustion reactor

    KAUST Repository

    Iloeje, Chukwunwike O.

    2017-01-11

    The rotary chemical looping combustion reactor has great potential for efficient integration with CO capture-enabled energy conversion systems. In earlier studies, we described a one-dimensional rotary reactor model, and used it to demonstrate the feasibility of continuous reactor operation. Though this detailed model provides a high resolution representation of the rotary reactor performance, it is too computationally expensive for studies that require multiple model evaluations. Specifically, it is not ideal for system-level studies where the reactor is a single component in an energy conversion system. In this study, we present a reduced fidelity model (RFM) of the rotary reactor that reduces computational cost and determines an optimal combination of variables that satisfy reactor design requirements. Simulation results for copper, nickel and iron-based oxygen carriers show a four-order of magnitude reduction in simulation time, and reasonable prediction accuracy. Deviations from the detailed reference model predictions range from 3% to 20%, depending on oxygen carrier type and operating conditions. This study also demonstrates how the reduced model can be modified to deal with both optimization and design oriented problems. A parametric study using the reduced model is then applied to analyze the sensitivity of the optimal reactor design to changes in selected operating and kinetic parameters. These studies show that temperature and activation energy have a greater impact on optimal geometry than parameters like pressure or feed fuel fraction for the selected oxygen carrier materials.

  10. Shaping abilities of two different engine-driven rotary nickel titanium systems or stainless steel balanced-force technique in mandibular molars.

    Science.gov (United States)

    Matwychuk, Michael J; Bowles, Walter R; McClanahan, Scott B; Hodges, Jim S; Pesun, Igor J

    2007-07-01

    The purpose of this study was to compare apical transportation, working-length changes, and instrumentation time by using nickel-titanium (Ni-Ti) rotary file systems (crown-down method) or stainless steel hand files (balanced-force technique) in mesiobuccal canals of extracted mandibular molars. The curvature of each canal was determined and teeth placed into three equivalent groups. Group 1 was instrumented with Sequence (Brasseler USA, Savannah, GA) rotary files, group 2 with Liberator (Miltex Inc, York, PA) rotary files, and group 3 with Flex-R (Union Broach, New York, NY) files. Pre- and postoperative radiographs were superimposed to measure loss of working length and apical transportation as shown by changes in radius of curvature and the long-axis canal angle. Sequence rotary files, Liberator rotary files, and Flex-R hand files had similar effects on apical canal transportation and changes in working length, with no significant differences detected among the 3 groups. Hand instrumentation times were longer than with either Ni-Ti rotary group, whereas the rotary NiTi groups had a higher incidence of fracture.

  11. Dual Spark Plugs For Stratified-Charge Rotary Engine

    Science.gov (United States)

    Abraham, John; Bracco, Frediano V.

    1996-01-01

    Fuel efficiency of stratified-charge, rotary, internal-combustion engine increased by improved design featuring dual spark plugs. Second spark plug ignites fuel on upstream side of main fuel injector; enabling faster burning and more nearly complete utilization of fuel.

  12. Dose Rate Calculations for Rotary Mode Core Sampling Exhauster

    CERN Document Server

    Foust, D J

    2000-01-01

    This document provides the calculated estimated dose rates for three external locations on the Rotary Mode Core Sampling (RMCS) exhauster HEPA filter housing, per the request of Characterization Field Engineering.

  13. Dose Rate Calculations for Rotary Mode Core Sampling Exhauster

    International Nuclear Information System (INIS)

    FOUST, D.J.

    2000-01-01

    This document provides the calculated estimated dose rates for three external locations on the Rotary Mode Core Sampling (RMCS) exhauster HEPA filter housing, per the request of Characterization Field Engineering

  14. Experimental analysis of IMEP in a rotary combustion engine

    Science.gov (United States)

    Schock, H. J.; Rice, W. J.; Meng, P. R.

    1981-01-01

    A real time indicated mean effective pressure measurement system is described which is used to judge proposed improvements in cycle efficiency of a rotary combustion engine. This is the first self-contained instrument that is capable of making real time measurements of IMEP in a rotary engine. Previous methods used require data recording and later processing using a digital computer. The unique features of this instrumentation include its ability to measure IMEP on a cycle by cycle, real time basis and the elimination of the need to differentiate volume function in real time. Measurements at two engine speeds (2000 and 3000 rpm) and a full range of loads are presented, although the instrument was designed to operate to speeds of 9000 rpm.

  15. SPH Simulation of Liquid Scattering from the Edge of a Rotary Atomizer

    Science.gov (United States)

    Izawa, Seiichiro; Ito, Takuya; Shigeta, Masaya; Fukunishi, Yu

    2013-11-01

    Three-dimensional incompressible SPH method is used to simulate the behavior of liquid scattering from the edge of a rotary atomizer. Rotary atomizers have been widely used for spraying, painting and coating, for instance, in the automobile industry. However, how the spray droplets are formed after leaving the edge of the rotary atomizer is not well understood, because the scale of the phenomenon is very small and the speed of rotation is very fast. The present computational result shows that while the liquid forms a film on the surface of the rotating disk of the atomizer, it quickly deforms into many thin columns after leaving the disk edge, and these columns soon break up into fine droplets which spread out in the radial direction. The size of droplets tends to become smaller with the increase in the disk rotating speed. The results show good agreement with the experimental observations.

  16. Dynamic behavior of a rotating delaminated composite beam including rotary inertia and shear deformation effects

    Directory of Open Access Journals (Sweden)

    Ramazan-Ali Jafari-Talookolaei

    2015-09-01

    Full Text Available A finite element (FE model is developed to study the free vibration of a rotating laminated composite beam with a single delamination. The rotary inertia and shear deformation effects, as well as the bending–extension, bending–twist and extension–twist coupling terms are taken into account in the FE model. Comparison between the numerical results of the present model and the results published in the literature verifies the validity of the present model. Furthermore, the effects of various parameters, such as delamination size and location, fiber orientation, hub radius, material anisotropy and rotating speed, on the vibration of the beam are studied in detail. These results provide useful information in the study of the free vibration of rotating delaminated composite beams.

  17. A smart rotary technique versus conventional pulpectomy for primary teeth: A randomized controlled clinical study.

    Science.gov (United States)

    Mokhtari, Negar; Shirazi, Alireza-Sarraf; Ebrahimi, Masoumeh

    2017-11-01

    Techniques with adequate accuracy of working length determination along with shorter duration of treatment in pulpectomy procedure seems to be essential in pediatric dentistry. The aim of the present study was to evaluate the accuracy of root canal length measurement with Root ZX II apex locator and rotary system in pulpectomy of primary teeth. In this randomized control clinical trial complete pulpectomy was performed on 80 mandibular primary molars in 80, 4-6-year-old children. The study population was randomly divided into case and control groups. In control group conventional pulpectomy was performed and in the case group working length was determined by electronic apex locator Root ZXII and instrumented with Mtwo rotary files. Statistical evaluation was performed using Mann-Whitney and Chi-Square tests ( P <0.05). There were no significant differences between electronic apex locator Root ZXII and conventional method in accuracy of root canal length determination. However significantly less time was needed for instrumenting with rotary files ( P =0.000). Considering the comparable results in accuracy of root canal length determination and the considerably shorter instrumentation time in Root ZXII apex locator and rotary system, it may be suggested for pulpectomy in primary molar teeth. Key words: Rotary technique, conventional technique, pulpectomy, primary teeth.

  18. Effect of rotary inertia of concentrated masses on the natural vibration of fluid conveying pipes

    International Nuclear Information System (INIS)

    Kang, Myeong Gie

    1999-01-01

    Effects of the rotary inertia of concentrated masses on the natural vibrations of fluid conveying pipes have been studied by theoretical modeling and computer simulation. For analysis, two boundary conditions for pipe ends, simply supported and clamped-clamped, are assumed and Galerkin's method is used for transformation of the governing equation to the eigenvalues problem and the natural frequencies and mode shapes for the system have been calculated by using the newly developed computer code. Moreover, the critical velocities related to a system instability have been investigated. The main conclusions for the present study are (1) rotary inertia gives much change on the higher natural frequencies and mode shapes and its effect is visible when it has small value, (2) The number and location of nodes can be changed by rotary inertia, (3) By introducing rotary inertia, the second natural frequency approaches to the first as the location of the concentrated mass approaches to the midspan of the pipe, and (4) The critical fluid velocities to initiate the system unstable are unchanged by introduction of rotary inertia and the first three velocities are π, 2π, and 3π for the simply supported pipe and 2π, 8.99 and 12.57 for the clamped-clamped pipe. (author). 16 refs., 7 figs., 3 tabs

  19. A novel redundant INS based on triple rotary inertial measurement units

    International Nuclear Information System (INIS)

    Chen, Gang; Li, Kui; Wang, Wei; Li, Peng

    2016-01-01

    Accuracy and reliability are two key performances of inertial navigation system (INS). Rotation modulation (RM) can attenuate the bias of inertial sensors and make it possible for INS to achieve higher navigation accuracy with lower-class sensors. Therefore, the conflict between the accuracy and cost of INS can be eased. Traditional system redundancy and recently researched sensor redundancy are two primary means to improve the reliability of INS. However, how to make the best use of the redundant information from redundant sensors hasn’t been studied adequately, especially in rotational INS. This paper proposed a novel triple rotary unit strapdown inertial navigation system (TRUSINS), which combines RM and sensor redundancy design to enhance the accuracy and reliability of rotational INS. Each rotary unit independently rotates to modulate the errors of two gyros and two accelerometers. Three units can provide double sets of measurements along all three axes of body frame to constitute a couple of INSs which make TRUSINS redundant. Experiments and simulations based on a prototype which is made up of six fiber-optic gyros with drift stability of 0.05° h −1 show that TRUSINS can achieve positioning accuracy of about 0.256 n mile h −1 , which is ten times better than that of a normal non-rotational INS with the same level inertial sensors. The theoretical analysis and the experimental results show that due to the advantage of the innovative structure, the designed fault detection and isolation (FDI) strategy can tolerate six sensor faults at most, and is proved to be effective and practical. Therefore, TRUSINS is particularly suitable and highly beneficial for the applications where high accuracy and high reliability is required. (paper)

  20. Surfzone monitoring using rotary wing unmanned aerial vehicles

    NARCIS (Netherlands)

    Brouwer, R.L.; De Schipper, M.A.; Rynne, P.F.; Graham, F.J.; Reniers, A.J.H.M.; Macmahan, J.H.

    2015-01-01

    This study investigates the potential of rotary wing unmanned aerial vehicles (UAVs) to monitor the surfzone. This paper shows that these UAVs are extremely flexible surveying platforms that can gather nearcontinuous moderate spatial resolution and high temporal resolution imagery from a fixed

  1. Design and multi-physics optimization of rotary MRF brakes

    Science.gov (United States)

    Topcu, Okan; Taşcıoğlu, Yiğit; Konukseven, Erhan İlhan

    2018-03-01

    Particle swarm optimization (PSO) is a popular method to solve the optimization problems. However, calculations for each particle will be excessive when the number of particles and complexity of the problem increases. As a result, the execution speed will be too slow to achieve the optimized solution. Thus, this paper proposes an automated design and optimization method for rotary MRF brakes and similar multi-physics problems. A modified PSO algorithm is developed for solving multi-physics engineering optimization problems. The difference between the proposed method and the conventional PSO is to split up the original single population into several subpopulations according to the division of labor. The distribution of tasks and the transfer of information to the next party have been inspired by behaviors of a hunting party. Simulation results show that the proposed modified PSO algorithm can overcome the problem of heavy computational burden of multi-physics problems while improving the accuracy. Wire type, MR fluid type, magnetic core material, and ideal current inputs have been determined by the optimization process. To the best of the authors' knowledge, this multi-physics approach is novel for optimizing rotary MRF brakes and the developed PSO algorithm is capable of solving other multi-physics engineering optimization problems. The proposed method has showed both better performance compared to the conventional PSO and also has provided small, lightweight, high impedance rotary MRF brake designs.

  2. Seismic qualification of the rotary relay for use in the Trojan and Diablo Canyon Auxiliary Safeguards Cabinets

    International Nuclear Information System (INIS)

    Riggio, M.D.; Jarecki, S.J.

    1977-10-01

    This report presents the results of the analysis performed for the seismic qualification of the rotary relay for use in the Trojan and Diablo Canyon Auxiliary Safeguards Cabinets. A finite element model of the cabinet was developed from seismic test results. This model was analytically subjected to a simulated 3D floor acceleration time history that enveloped, simultaneously, the Trojan and the June 1969 Diablo Canyon Safe Shutdown Earthquake requirements. The dynamic response of the cabinet at the mounting location of the rotary relays was determined. The calculated acceleration time histories were converted to response spectra and these response spectra were compared to the test response spectra successfully achieved during the rotary relay seismic qualification tests. It was found that the dynamic motion levels at the rotary relays, when mounted in the Trojan or Diablo Canyon Auxiliary Safeguards Cabinets, do not exceed the levels for which they were previously seismically qualified by tests. Consequently, the rotary relays are seismically qualified for use in the Trojan or Diablo Canyon Auxiliary Safeguards Cabinets

  3. Metallurgical characterization of a new nickel-titanium wire for rotary endodontic instruments.

    Science.gov (United States)

    Alapati, Satish B; Brantley, William A; Iijima, Masahiro; Clark, William A T; Kovarik, Libor; Buie, Caesar; Liu, Jie; Ben Johnson, William

    2009-11-01

    A novel thermomechanical processing procedure has been developed that yields a superelastic (SE) nickel-titanium (NiTi) wire (M-Wire) that laboratory testing shows has improved mechanical properties compared with conventional SE austenitic NiTi wires used for manufacture of rotary instruments. The objective of this study was to determine the origin of the improved mechanical properties. Specimens from 2 batches of M-Wire prepared under different processing conditions and from 1 batch of standard-processed SE wire for rotary instruments were examined by scanning transmission electron microscopy, temperature-modulated differential scanning calorimetry, micro-x-ray diffraction, and scanning electron microscopy with x-ray energy-dispersive spectrometric analyses. The processing for M-Wire yields a microstructure containing martensite, that the proportions of NiTi phases depend on processing conditions, and that the microstructure exhibits pronounced evidence of alloy strengthening. The presence of Ti(2)Ni precipitates in both microstructures indicates that M-Wire and the conventional SE wire for rotary instruments are titanium-rich.

  4. A comparison of apical transportation between FlexMaster and Twisted Files rotary instruments.

    Science.gov (United States)

    Duran-Sindreu, Fernando; García, Marc; Olivieri, Juan Gonzalo; Mercadé, Montse; Morelló, Sergio; Roig, Miguel

    2012-07-01

    The aim of this study was to evaluate apical transportation in root canals after the use of Twisted Files (TF; SybronEndo, Orange, CA) and FlexMaster (VDW, Munich, Germany) #40/04 rotary files. A double-digital radiographic technique was used to compare apical transportation between the TF and FlexMaster systems. Each rotary system was used to instrument mesial canals from 80 extracted mandibular molars. The central axes of the file imaged before instrumentation (#15 K-file) and the master apical rotary file (#40/04) were superimposed digitally. AutoCAD 2008 (Autodesk Inc, San Rafael, CA) was used to measure apical transportation at 0.5 mm from the working length (WL). The data were analyzed using the Student's t test, and significance was set at P < .05. The mean amount of apical transportation at 0.5 mm from the WL was 0.17 ± 0.09 mm for the FlexMaster group and 0.19 ± 0.12 mm for the TF group. No statistically significant differences in apical transportation were found between the 2 groups. Under the conditions of the study, no statistically significant differences in apical transportation were observed between FlexMaster and TF rotary files. Copyright © 2012 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  5. Equivalent Circuit Modeling of a Rotary Piezoelectric Motor

    DEFF Research Database (Denmark)

    El, Ghouti N.; Helbo, Jan

    2000-01-01

    In this paper, an enhanced equivalent circuit model of a rotary traveling wave piezoelectric ultrasonic motor "shinsei type USR60" is derived. The modeling is performed on the basis of an empirical approach combined with the electrical network method and some simplification assumptions about the ...

  6. Rotary adsorbers for waste air purification and solvent recovery

    International Nuclear Information System (INIS)

    Konrad, G.; Eigenberger, G.

    1994-01-01

    Rotary Adsorbers for Waste Air Purification and Solvent Recovery. Thanks to their compact construction and low pressure drops, adsorbers with rotating adsorbent beds are highly suitable both for retrofitting of waste air purification units and generally for the removal of absorbable components from gas streams. When used in conjunction with straightforward hot gas desorption they permit almost complete purification of gas flows with concomitant concentration of the separated components in the desorbate by a factor of 10 to 20. They can also be used in conjunction with recovery of the separated components by partial condensation of the desorbate. Owing to the fixed coupling of adsorption and desorption times, which is determined by the geometry of the unit, the behaviour of the system is distinctly different from that of conventional multiple bed systems in cyclic operation. A detailed model description and computer simulation of operating behaviour are particularly useful for their analysis. It is shown that the behaviour of commercially available rotor concepts can be much better understood in this way and new concepts for exhaust air purification with integrated solvent recovery can be developed which are characterised by significantly reduced energy requirements for desorption and condensation. (orig.) [de

  7. Design and construction of a novel rotary magnetostrictive motor

    Science.gov (United States)

    Zhou, Nanjia; Blatchley, Charles C.; Ibeh, Christopher C.

    2009-04-01

    Magnetostriction can be used to induce linear incremental motion, which is effective in giant magnetostrictive inchworm motors. Such motors possess the advantage of combining small step incremental motion with large force. However, continuous rotation may be preferred in practical applications. This paper describes a novel magnetostrictive rotary motor using terfenol-D (Tb0.3Dy0.7Fe1.9) material as the driving element. The motor is constructed of two giant magnetostrictive actuators with shell structured flexure-hinge and leaf springs. These two actuators are placed in a perpendicular position to minimize the coupling displacement of the two actuators. The principal design parameters of the actuators and strain amplifiers are optimally determined, and its static analysis is undertaken through finite element analysis software. The small movements of the magnetostrictive actuators are magnified by about three times using oval shell structured amplifiers. When two sinusoidal wave currents with 90° phase shift are applied to the magnetostrictive actuators, purely rotational movement can be produced as in the orbit of a Lissajous diagram in an oscillograph, and this movement is used to drive the rotor of the motor. A prototype has been constructed and tested.

  8. Sway control method and system for rotary cranes

    Science.gov (United States)

    Robinett, Rush D.; Parker, Gordon G.; Feddema, John T.; Dohrmann, Clark R.; Petterson, Ben J.

    1999-01-01

    Methods and apparatuses for reducing the oscillatory motion of rotary crane payloads during operator-commanded or computer-controlled maneuvers. An Input-shaping filter receives input signals from multiple operator input devices and converts them into output signals readable by the crane controller to dampen the payload tangential and radial sway associated with rotation of the jib. The input signals are characterized by a hub rotation trajectory .gamma.(t), which includes a jib angular acceleration .gamma., a trolley acceleration x, and a load-line length velocity L. The system state variables are characterized by a tangential rotation angle .theta.(t) and a radial rotation angle .phi.(t) of the load-line. The coupled equations of motion governing the filter are non-linear and configuration-dependent. In one embodiment, a filter is provided between the operator and the crane for filtering undesired frequencies from the angular .gamma. and trolley x velocities to suppress payload oscillation. In another embodiment, crane commands are computer generated and controlled to suppress vibration of the payload using a postulated asymmetrical shape for the acceleration profiles of the jib, which profiles are uniquely determined by a set of parameters (including the acceleration pulse amplitude and the duration and coast time between pulses), or a dynamic programming approach.

  9. Comparison of dentinal damage induced by different nickel-titanium rotary instruments during canal preparation: An in vitro study.

    Science.gov (United States)

    Garg, Shiwani; Mahajan, Pardeep; Thaman, Deepa; Monga, Prashant

    2015-01-01

    To compare dentinal damage caused by hand and rotary nickel-titanium instruments using ProTaper, K3 Endo, and Easy RaCe systems after root canal preparation. One hundred and fifty freshly extracted mandibular premolars were randomly divided into five experimental groups of 30 teeth each and biomechanical preparation was done: Group 1 with unprepared teeth; Group 2 were prepared with hand files; Group 3 with ProTaper rotary instruments; Group 4 with K3 rotary; Group 5 with Easy RaCe rotary instruments. Then, roots were cut horizontally at 3, 6, and 9 mm from apex and were viewed under stereomicroscope. The presence of dentinal defects was noted. Groups were analyzed with the Chi-square test. Significant difference was seen between groups. No defects were found in unprepared roots and those prepared with hand files. ProTaper, K3 rotary, and Easy RaCe preparations resulted in dentinal defects in 23.3%, 10%, and 16.7% of teeth, respectively. More defects were shown in coronal and middle sections, and no defect was seen in apical third. The present study revealed that use of rotary instruments could result in an increased chance for dentinal defects as compared to hand instrumentation.

  10. High speed rotary drum

    Energy Technology Data Exchange (ETDEWEB)

    Sagara, H

    1970-03-25

    A high speed rotary drum is disclosed in which the rotor vessel is a double-wall structure comprising an inner wave-shaped pipe inserted coaxially within an outer straight pipe, the object being to provide a strengthened composite light-weight structure. Since force induced axial deformation of the straight pipe and radial deformation of the corrugated pipe are small, the composite effectively resists external forces and, if the waves of the inner pipe are given a sufficient amplitude, the thickness of both pipes may be reduced to lower the overall weight. Thus high angular velocities can be obtained to separate U/sup 235/ from gaseous UF/sub 6/.

  11. Rotary engine cooling system

    Science.gov (United States)

    Jones, Charles (Inventor); Gigon, Richard M. (Inventor); Blum, Edward J. (Inventor)

    1985-01-01

    A rotary engine has a substantially trochoidal-shaped housing cavity in which a rotor planetates. A cooling system for the engine directs coolant along a single series path consisting of series connected groups of passages. Coolant enters near the intake port, passes downwardly and axially through the cooler regions of the engine, then passes upwardly and axially through the hotter regions. By first flowing through the coolest regions, coolant pressure is reduced, thus reducing the saturation temperature of the coolant and thereby enhancing the nucleate boiling heat transfer mechanism which predominates in the high heat flux region of the engine during high power level operation.

  12. Improvements in or relating to rotary drive mechanisms

    International Nuclear Information System (INIS)

    Lodge, J.A.

    1981-01-01

    The invention relates to rotary drive mechanisms and relates especially, though not exclusively, to such mechanisms for use in rotating a source of penetrating radiation, such as X-radiation, in steps around a body, in the course of a computerised tomographic (CAT) examination of the body. (author)

  13. The Rotary Combustion Engine: a Candidate for General Aviation. [conferences

    Science.gov (United States)

    1978-01-01

    The state of development of the rotary combustion engine is discussed. The nonturbine engine research programs for general aviation and future requirements for general aviation powerplants are emphasized.

  14. A rotary pneumatic actuator for the actuation of the exoskeleton knee joint

    Directory of Open Access Journals (Sweden)

    Jobin Varghese

    2017-07-01

    Full Text Available Rotary pneumatic actuators that are made out of linear one are always best suited for exoskeleton joint actuation due to its inherent power to weight ratio. This work is a modified version of knee actuation system that has already been developed and major modifications are made in order to make it more suitable for human wearing and also to reduce its bulkiness and complexity. The considered actuator system is a rotary actuator where a pulley converts the linear motion of the standard pneumatic piston into the rotary motion. To prove the capability of the actuator, its performance characteristics such as torque and power produced are compared to the required torque and power at the knee joint of the exoskeleton in swing phase and are found to be excellent. The two-way analysis of variance (ANOVA is performed to find the effect of the throat area valve on knee angle. The ANOVA shows the significant effect of the throat area variation on the knee angle flexion made by the proposed actuator. A relationship between the throat area of flow control valve, that is connected to the exit port of the direction control valve, and angular displacement of the knee joint has been formulated. This relationship can be used to design a control system to regulate the mass flow rate of air at the exit and hence the angular velocity of the knee joint can be controlled. Keywords: Driven pulley, Flow control valve, Rotary, Pneumatic cylinder

  15. Development of simulation code for FBR spent fuel dissolution with rotary drum type continuous dissolver

    International Nuclear Information System (INIS)

    Sano, Yuichi; Katsurai, Kiyomichi; Washiya, Tadahiro; Koizumi, Tsutomu; Matsumoto, Satoshi

    2011-01-01

    Japan Atomic Energy Agency (JAEA) has been studying rotary drum type continuous dissolver for FBR spent fuel dissolution. For estimating the fuel dissolution behavior under several operational conditions in this dissolver, we have been developing the simulation code, PLUM, which mainly consists of 3 modules for calculating chemical reaction, mass transfer and thermal balance in the rotary drum type continuous dissolver. Under the various conditions where dissolution experiments were carried out with the batch-wise dissolver for FBR spent fuel and with the rotary drum type continuous dissolver for UO 2 fuel, it was confirmed that the fuel dissolution behaviors calculated by the PLUM code showed good agreement with the experimental ones. Based on this result, the condition for obtaining the dissolver solution with high HM (heavy metal : U and Pu) concentration (∼500g/L), which is required for the next step, i.e. crystallization process, was also analyzed by this code and appropriate operational conditions with the rotary drum type continuous dissolver, such as feedrate, concentration and temperature of nitric acid, could be clarified. (author)

  16. Applying rotary jet heads for mixing and mass transfer in a forced recirculation tank reactor system

    DEFF Research Database (Denmark)

    Nordkvist, Mikkel; Grotkjær, Thomas; Hummer, J.S.

    2003-01-01

    or an external loop.In this study, we determine mixing times in water and CMC solutions and oxygen mass transfer coefficients in water for a tank reactor system where a small fraction of the total liquid volume is rapidly circulated through an external loop and injected through the nozzles of rotary jet heads....... The system has a very simple design with no internal baffles or heat exchange area, and between batches the rotary jet heads are used for cleaning in place.Mixing time decreases and mass transfer increases with increasing circulation flow rate. For nozzle diameters between 5.5 and 10 mm and with one or two...... rotary jet heads, it is shown that a remarkable saving in power input for a fixed mixing time or mass transfer coefficient can be obtained by using a large nozzle diameter and two rather than one rotary jet heads.At the experimental conditions of the study the system is scaleable by simple formulas...

  17. Development of a Rotary Microfilter for SRS HLW Applications

    International Nuclear Information System (INIS)

    MICHAEL, POIRIER

    2004-01-01

    The processing rate of Savannah River Site high level waste decontamination processes are limited by the flow rate of the solid-liquid separation. The baseline process, using a 0.1 micron cross flow filter, produces 0.02 gpm/ft2 of filtrate under expected operating conditions. Savannah River National Laboratory personnel identified the rotary microfilter as a technology that could significantly increase filter flux, with throughput improvements of as much as 10X for that specific operation. With funding from the Department of Energy Office of Cleanup Technologies, SRNL personnel are evaluating and developing the rotary microfilter for radioactive service at SRS. This work includes pilot-scale and actual waste testing to evaluate system reliability, the impact of radiation on system components, the filter flux for a variety of waste streams, and relative performance for alternative filter media

  18. Sealing of rotary drums for operation under pressurized conditions

    International Nuclear Information System (INIS)

    Shirvani, M.; Khanof, M. H.; Yousefi, M. R.; Sadighi, S.

    2006-01-01

    In practice, rotary drums are always designed for operation under vacuum conditions. In this paper, a novel technique is proposed for sealing the rotary drums under pressurized conditions. The proposed system is based on applying a secondary pressurized volume around the leaking gap of the drum. By controlling the pressure of this volume above the pressure of the drum, it will be possible to prevent from any leakage of gases to the ambient. The objective of a controller in this system is that the pressure of secondary volume be kept above the pressure of the drum in spite of the disturbances which may be exerted on the system by the wind outside the drum. The control system is also required to trace the variations in the drum pressure with the least fluctuations in the pressure difference among the drum and the volume

  19. Combustion of large solid fuels in cement rotary kilns

    DEFF Research Database (Denmark)

    Nielsen, Anders Rooma

    (MBM), waste wood, sewage sludge, paper and plastics. The alternative fuel share of the total energy varies significantly from region to region, but the general trend is towards increased alternative fuel utilization. Solid alternative fuels typically have physical and chemical properties that differ...... from traditional solid fossil fuels. This creates a need for new combustion equipment or modification of existing kiln systems, because alternative fuels may influence process stability and product quality. Process stability is mainly influenced by exposing the raw material bed in the rotary kiln...... oxidation is a slow process which may greatly reduce the amounts of solid fuels to be utilized in the material inlet end of rotary kilns due to the limited residence time. Several parameters control the rate of char oxidation: a) bulk oxygen concentration, b) mass transfer rate of oxygen to char particles...

  20. Carbon Fiber Reinforced Carbon Composites Rotary Valves for Internal Combustion Engines

    Science.gov (United States)

    Northam, G. Burton (Inventor); Ransone, Philip O. (Inventor); Rivers, H. Kevin (Inventor)

    1999-01-01

    Carbon fiber reinforced carbon composite rotary, sleeve, and disc valves for internal combustion engines and the like are disclosed. The valves are formed from knitted or braided or warp-locked carbon fiber shapes. Also disclosed are valves fabricated from woven carbon fibers and from molded carbon matrix material. The valves of the present invention with their very low coefficient of thermal expansion and excellent thermal and self-lubrication properties, do not present the sealing and lubrication problems that have prevented rotary, sleeve, and disc valves from operating efficiently and reliably in the past. Also disclosed are a sealing tang to further improve sealing capabilities and anti-oxidation treatments.

  1. Method of start-up of rotary plug sealing devices in FBR type reactors

    International Nuclear Information System (INIS)

    Sakuragi, Masanori; Akita, Haruo

    1980-01-01

    Purpose: To rapidly and safely start-up the rotary plug sealing device by controlling to eliminate the pressure difference in the pressures of gases exerting on the liquid surfaces in the inner and the outer cylinders of a sealing alloy vessel in the rotary plug of a FBR type reactor. Method: In a case where an abnormal state results in the pressure difference of gases exerted on the liquid surfaces in the inner and the outer cylinders of a vessel charged with sealing alloy in a rotary plug and the sealing valve for the back-up gas supply tube is rapidly closed to seal the sealing portion, the pressure in the gas supply tube is controlled so that the pressure difference in the gases exerted on the liquid surfaces in the inner and outer cylinders while closing the sealing valve. Then, after conforming that the pressure is controlled to a predetermined level at which the pressure difference can be regarded to be zero, the sealing valve is gradually opened while regulating the pressure in the gas supply tube so as to maintain the pressure difference to a predetermined level. This prevents the occurrence of external disturbances upon opening of the sealing valve and enables rapid and safety start-up for the rotary plug sealing device. (Moriyama, K.)

  2. Comparison of cyclic fatigue resistance of three different rotary nickel-titanium instruments designed for retreatment.

    Science.gov (United States)

    Inan, Ugur; Aydin, Cumhur

    2012-01-01

    A number of rotary nickel-titanium (NiTi) systems have been developed to provide better, faster, and easier cleaning and shaping of the root canal system, and recently, rotary NiTi systems designed for root canal retreatment have been introduced. Because the main problem with the rotary NiTi files is fracture, the aim of this study was to compare the cyclic fatigue resistance of 3 different rotary NiTi systems designed for root canal retreatment. Total of 60 instruments of 3 different rotary NiTi systems designed for root canal retreatment were used in this study. Twenty R-Endo R3, 20 ProTaper D3, and 20 Mtwo R (Retreatment) 25.05 instruments were tested. Cyclic fatigue testing of instruments was performed by using a device that allowed the instruments to rotate freely inside an artificial canal. Each instrument was rotated until fracture occurred, and the number of cycles to fracture for each instrument was calculated. Representative samples were also evaluated under a scanning electron microscope to confirm the fracture was flexural. Data were analyzed by using 1-way analysis of variance test. R-Endo R3 instruments showed better cyclic fatigue resistance than ProTaper D3 and Mtwo R 25.05 instruments, and the difference was statistically significant (P instruments were more resistant to fatigue failure than ProTaper D3 and Mtwo R 25.05. Copyright © 2012 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  3. Rotary klubi premeeris Politsei- ja Piirivalveameti töötajaid

    Index Scriptorium Estoniae

    2012-01-01

    Tallinna Rotary klubi noorte politseinike ning parima koerajuhi ja teenistuskoera preemia võitnutest: Raili Pärn, Marit Abram, Valur Pajumäe koeraga Golttvizen Hof Dixon, Hendri Lilbok ja Martin Torim

  4. Performance and efficiency evaluation and heat release study of a direct-injection stratified-charge rotary engine

    Science.gov (United States)

    Nguyen, H. L.; Addy, H. E.; Bond, T. H.; Lee, C. M.; Chun, K. S.

    1987-01-01

    A computer simulation which models engine performance of the Direct Injection Stratified Charge (DISC) rotary engines was used to study the effect of variations in engine design and operating parameters on engine performance and efficiency of an Outboard Marine Corporation (OMC) experimental rotary combustion engine. Engine pressure data were used in a heat release analysis to study the effects of heat transfer, leakage, and crevice flows. Predicted engine data were compared with experimental test data over a range of engine speeds and loads. An examination of methods to improve the performance of the rotary engine using advanced heat engine concepts such as faster combustion, reduced leakage, and turbocharging is also presented.

  5. Tank 241-BY-105 rotary core sampling and analysis plan

    International Nuclear Information System (INIS)

    Sasaki, L.M.

    1995-01-01

    This Sampling and Analysis Plan (SAP) identifies characterization objectives pertaining to sample collection, laboratory analytical evaluation, and reporting requirements for two rotary-mode core samples from tank 241-BY-105 (BY-105)

  6. Specific application of burnup credit for MOX PWR fuels in the rotary dissolver

    International Nuclear Information System (INIS)

    Caplin, Gregory; Coulaud, Alexandre; Klenov, Pavel; Toubon, Herve

    2003-01-01

    In prospect of a Mixed OXide spent fuels processing in the rotary dissolver in COGEMA/La Hague plant, it is interesting to quantify the criticality-safety margins from the burnup credit. Using the current production computer codes and considering a minimal fuel irradiation of 3 200 megawatt-day per ton, this paper shows the impact of burnup credit on industrial parameters such as the permissible concentration in the dissolution solution or the permissible oxide mass in the rotary dissolver. Moreover, the burnup credit is broken down into five sequences in order to quantify the contribution of fissile nuclides decrease and of minor actinides and fission products formation. The implementation of the burnup credit in the criticality-safety analysis of the rotary dissolver may lead to workable industrial conditions for the particular MOX fuel studied. It can eventually be noticed that minor actinides contribution is negligible and that considering only the six major fission products is sufficient, owing to the weak fuel irradiation contemplated. (author)

  7. Design analysis and comparison between standard and rotary porting systems for IC engine

    Energy Technology Data Exchange (ETDEWEB)

    Palmisano, R.; Ng, H.D. [Concordia Univ., Montreal, PQ (Canada). Dept. of Mechanical and Industrial Engineering

    2009-07-01

    A method of improving the efficiency of an internal combustion engine was presented. The proposed design used a new sealing technology to optimize a rotary valve design. The design was compared with standard poppet porting system using a computer aided engineering (CAE) method. A double port cylinder configuration was used in order to allow continuous flow into the chamber and minimize the exposed surface area in the combustion chamber. The design also minimized distortion on the component when exposed to high condensation pressures. A transfer case was used to allow for easy adaptation of the configuration to a multi-cylinder engine. A mechanism dynamics extension (MDO) program was used to conduct dynamic analyses on the rotary and standard valve porting systems. The study showed that the poppet system required 62 times more torque than the new rotary valve design. It was concluded that further research is needed to examine the flow properties of both designs. 2 refs., 6 figs.

  8. Efficient parallel implicit methods for rotary-wing aerodynamics calculations

    Science.gov (United States)

    Wissink, Andrew M.

    Euler/Navier-Stokes Computational Fluid Dynamics (CFD) methods are commonly used for prediction of the aerodynamics and aeroacoustics of modern rotary-wing aircraft. However, their widespread application to large complex problems is limited lack of adequate computing power. Parallel processing offers the potential for dramatic increases in computing power, but most conventional implicit solution methods are inefficient in parallel and new techniques must be adopted to realize its potential. This work proposes alternative implicit schemes for Euler/Navier-Stokes rotary-wing calculations which are robust and efficient in parallel. The first part of this work proposes an efficient parallelizable modification of the Lower Upper-Symmetric Gauss Seidel (LU-SGS) implicit operator used in the well-known Transonic Unsteady Rotor Navier Stokes (TURNS) code. The new hybrid LU-SGS scheme couples a point-relaxation approach of the Data Parallel-Lower Upper Relaxation (DP-LUR) algorithm for inter-processor communication with the Symmetric Gauss Seidel algorithm of LU-SGS for on-processor computations. With the modified operator, TURNS is implemented in parallel using Message Passing Interface (MPI) for communication. Numerical performance and parallel efficiency are evaluated on the IBM SP2 and Thinking Machines CM-5 multi-processors for a variety of steady-state and unsteady test cases. The hybrid LU-SGS scheme maintains the numerical performance of the original LU-SGS algorithm in all cases and shows a good degree of parallel efficiency. It experiences a higher degree of robustness than DP-LUR for third-order upwind solutions. The second part of this work examines use of Krylov subspace iterative solvers for the nonlinear CFD solutions. The hybrid LU-SGS scheme is used as a parallelizable preconditioner. Two iterative methods are tested, Generalized Minimum Residual (GMRES) and Orthogonal s-Step Generalized Conjugate Residual (OSGCR). The Newton method demonstrates good

  9. How to manage MTTF larger than 30,000hr on rotary cryocoolers

    Science.gov (United States)

    Cauquil, Jean-Marc; Seguineau, Cédric; Martin, Jean-Yves; Van-Acker, Sébastien; Benschop, Tonny

    2017-05-01

    The cooled IR detectors are used in a wide range of applications. Most of the time, the cryocoolers are one of the components dimensioning the lifetime of the system. Indeed, Stirling coolers are mechanical systems where wear occurs on millimetric mechanisms. The exponential law classically used in electronics for Mean Time to Failure (MTTF) calculation cannot be directly used for mechanical devices. With new applications for thermal sensor like border surveillance, an increasing reliability has become mandatory for rotary cooler. The current needs are above several tens of thousands of continuous hour of cooling. Thales Cryogenics made specific development on that topic, for both linear and rotary applications. The time needed for validating changes in processes through suited experimental design is hardly affordable by following a robust and rigorous standard scientific approach. The targeted Mean Time to Failure (MTTF) led us to adopt an innovative approach to keep development phases in line with expected time to market. This innovative approach is today widespread on all of Thales Cryogenics rotary products and results in a proven increase of MTTF for RM2, RM3 and recently RM1. This paper will then focused on the current MTTF figures measured on RM1, RM2 and RM3. After explaining the limit of a conventional approach, the paper will then describe the current method. At last, the authors will explain how these principles are taken into account for the new SWaP rotary cooler of Thales Cryogénie SAS.

  10. A new confined high pressure rotary shear apparatus: preliminary results

    Science.gov (United States)

    Faulkner, D.; Coughlan, G.; Bedford, J. D.

    2017-12-01

    The frictional properties of fault zone materials, and their evolution during slip, are of paramount importance for determining the earthquake mechanics of large tectonic faults. Friction is a parameter that is difficult to determine from seismological methods so much of our understanding comes from experiment. Rotary shear apparatuses have been widely used in experimental studies to elucidate the frictional properties of faults under realistic earthquake slip velocities (0.1-10 m/s) and displacements (>20 m). However one technical limitation of rotary shear experiments at seismic slip rates has been the lack of confinement. This has led to a limit on the normal stress (due to the strength of the forcing blocks) and also a lack of control of measurements of the pore fluid pressure. Here we present the first preliminary results from a rotary shear apparatus that has been developed to attempt to address this issue. The new fully confined ring shear apparatus has a fast-acting servo-hydraulic confining pressure system of up to 200 MPa and a servo-controlled upstream and downstream pore pressure system of up to 200 MPa. Displacement rates of 0.01μ/s to 2 m/s can be achieved. Fault gouge samples can therefore be sheared at earthquake speed whilst being subject to pressures typically associated with the depth of earthquake nucleation.

  11. Post endodontic pain following single-visit root canal preparation with rotary vs reciprocating instruments: a meta-analysis of randomized clinical trials.

    Science.gov (United States)

    Hou, Xiao-Mei; Su, Zheng; Hou, Ben-Xiang

    2017-05-25

    In endodontic therapy, continuous rotary instrumentation reduced debris compared to reciprocal instrumentation, which might affect the incidence of post-endodontic pain (PP). The aim of our study was to assess whether PP incidence and levels were influenced by the choice of rotary or reciprocal instruments. In this meta-analysis the Pubmed and EM databases were searched for prospective clinical randomized trials published before April 20, 2016, using combinations of the keywords: root canal preparation/instrumentation/treatment/therapy; post-operative/endodontic pain; reciprocal and rotary instruments. Three studies were included, involving a total of 1,317 patients, 659 treated with reciprocating instruments and 658 treated with rotary instruments. PP was reported in 139 patients in the reciprocating group and 172 in the rotary group. The PP incidence odds ratio was 1.27 with 95% confidence interval (CI) (0.25, 6.52) favoring rotary instruments. The mild, moderate and severe PP levels odds ratios were 0.31 (0.11, 0.84), 2.24 (0.66, 7.59) and 11.71 (0.63, 218.15), respectively. No evidence of publication bias was found. Rotary instrument choice in endodontic therapy is associated with a lower incidence of PP than reciprocating instruments, while reciprocating instruments are associated with less mild PP incidence.

  12. Design a Fuzzy Logic Controller for a Rotary Flexible Joint Robotic Arm

    Directory of Open Access Journals (Sweden)

    Jalani Jamaludin

    2018-01-01

    Full Text Available The purpose of this research is to design a fuzzy logic feedback controller (FLC in order to control a desired tip angle position a rotary flexible joint robotic arm. The FLC is also employed to dampen the vibration emanated from a rotary flexible joint robotic arm when reaching a desired tip angle position. The performance of FLC is tested in simulation and experiment. It is found that the FLC is successfully designed, applied and tested. The results show that fuzzy logic controller performed satisfactorily control a desired tip angle position and reduce the oscillations.

  13. In the zone - first rotary steerable liner-while-drilling system; Drilling technology

    Energy Technology Data Exchange (ETDEWEB)

    2010-07-01

    Statoil recently successfully tested the world's first rotary steerable liner-while-drilling system from its Brage platform in the Norwegian sector of the North Sea. This innovative technology - with applications in new and mature fields - was jointly developed by Statoil and Baker Hughes Incorporated. The concept of a rotary steerable system that gives operators the ability to accurately drill and log three-dimensional well profiles with a liner attached directly to the drillstring is entirely new. The system is designed to withstand high circulation rates and high torque loads while providing liner connect and disconnect capabilities. (Author)

  14. Piezoelectric Versus Conventional Rotary Techniques for Impacted Third Molar Extraction

    Science.gov (United States)

    Jiang, Qian; Qiu, Yating; Yang, Chi; Yang, Jingyun; Chen, Minjie; Zhang, Zhiyuan

    2015-01-01

    Abstract Impacted third molars are frequently encountered in clinical work. Surgical removal of impacted third molars is often required to prevent clinical symptoms. Traditional rotary cutting instruments are potentially injurious, and piezosurgery, as a new osteotomy technique, has been introduced in oral and maxillofacial surgery. No consistent conclusion has been reached regarding whether this new technique is associated with fewer or less severe postoperative sequelae after third molar extraction. The aim of this study was to compare piezosurgery with rotary osteotomy techniques, with regard to surgery time and the severity of postoperative sequelae, including pain, swelling, and trismus. We conducted a systematic literature search in the Cochrane Library, PubMed, Embase, and Google Scholar. The eligibility criteria of this study included the following: the patients were clearly diagnosed as having impacted mandibular third molars; the patients underwent piezosurgery osteotomy, and in the control group rotary osteotomy techniques, for removing impacted third molars; the outcomes of interest include surgery time, trismus, swelling or pain; the studies are randomized controlled trials. We used random-effects models to calculate the difference in the outcomes, and the corresponding 95% confidence interval. We calculated the weighted mean difference if the trials used the same measurement, and a standardized mean difference if otherwise. A total of seven studies met the eligibility criteria and were included in our analysis. Compared with rotary osteotomy, patients undergoing piezosurgery experienced longer surgery time (mean difference 4.13 minutes, 95% confidence interval 2.75–5.52, P piezosurgery groups. The number of included randomized controlled trials and the sample size of each trial were relatively small, double blinding was not possible, and cost analysis was unavailable due to a lack of data. Our meta-analysis indicates that although patients

  15. Thermal treatment of medical waste in a rotary kiln.

    Science.gov (United States)

    Bujak, J

    2015-10-01

    This paper presents the results of a study of an experimental system with thermal treatment (incineration) of medical waste conducted at a large complex of hospital facilities. The studies were conducted for a period of one month. The processing system was analysed in terms of the energy, environmental and economic aspects. A rotary combustion chamber was designed and built with the strictly assumed length to inner diameter ratio of 4:1. In terms of energy, the temperature distribution was tested in the rotary kiln, secondary combustion (afterburner) chamber and heat recovery system. Calorific value of medical waste was 25.0 MJ/kg and the thermal efficiency of the entire system equalled 66.8%. Next, measurements of the pollutant emissions into the atmosphere were performed. Due to the nature of the disposed waste, particular attention was paid to the one-minute average values of carbon oxide and volatile organic compounds as well as hydrochloride, hydrogen fluoride, sulphur dioxide and total dust. Maximum content of non-oxidized organic compounds in slag and bottom ash were also verified during the analyses. The best rotary speed for the combustion chamber was selected to obtain proper afterburning of the bottom slag. Total organic carbon content was 2.9%. The test results were used to determine the basic economic indicators of the test system for evaluating the profitability of its construction. Simple payback time (SPB) for capital expenditures on the implementation of the project was 4 years. Copyright © 2015 Elsevier Ltd. All rights reserved.

  16. An in-vitro comparison of canal debridement efficiency between three systems of Rotary, Reciprocal and Vertical

    Directory of Open Access Journals (Sweden)

    Sheykhrezaee MS.

    2004-08-01

    Full Text Available Statement of Problem: Total removal of tissues and remnant microorganisms as well as canal shaping are the essential objectives of endodontic therapy. A successful endodontic treatment is obtained through Shilder’s principals, however; complete observation of this technique using stainless steel files manually is problematic and time-consuming. Modern technology, in order to eliminate such problems, has presented new facilities such as Nickel-Titanium (NiTi files and engine driven instruments. Purpose: The aim of this in-vitro study was to compare the canal debridement efficiency of three engine driven instruments: Rotary, Reciprocal and Vertical. Materials and Methods: In this experimental study, 60 mesial roots of human first and second mandibular molars were divided into three groups randomly. In each sample, one canal was considered as case, the other one as control. Files used in Reciprocal and vertical groups were of handy Ni-Ti type and in rotary group, rotary Ni-Ti files were used. After debridement, the roots were sectioned at 3mm and 5mm from anatomic apex, stained and examined under light microscope. Comparison criteria between case and control groups were based on residual debris and predentin and the level of root canal preparation and shaping after debridement. Data were subjected to kruskal-Wallis non-parametric test. Results: There was no significant difference between the efficiency of debridement at 3mm and 5mm sections between all groups. But difference in time consumption was significant ranked from the shortest to the longest as rotary, reciprocal and vertical. Conclusion: The efficiency of debridement between the three automated instruments was approximately equal, however; the instrumentation time was different between three groups. Rotary system was the fastest one, as compared with reciprocal (second and vertical (last. It may be concluded that rotary system has a superiority over the other two groups in conventional

  17. Linear or Rotary Actuator Using Electromagnetic Driven Hammer as Prime Mover

    Science.gov (United States)

    Paine, Jeffrey S. N. (Inventor); Smith, Byron F. (Inventor); Sesler, Joshua J. (Inventor); Paine, Matthew T. (Inventor); McMahan, Bert K. (Inventor); McMahan, Mark C. (Inventor)

    2018-01-01

    We claim a hammer driven actuator that uses the fast-motion, low-force characteristics of an electro-magnetic or similar prime mover to develop kinetic energy that can be transformed via a friction interface to produce a higher-force, lower-speed linear or rotary actuator by using a hammering process to produce a series of individual steps. Such a system can be implemented using a voice-coil, electro-mechanical solenoid or similar prime mover. Where a typical actuator provides limited range of motion or low force, the range of motion of a linear or rotary impact driven motor can be configured to provide large displacements which are not limited by the characteristic dimensions of the prime mover.

  18. Engineering study of the rotary-vee engine concept

    Science.gov (United States)

    Willis, Edward A.; Bartrand, Timothy A.; Beard, John E.

    1989-01-01

    The applicable thermodynamic cycle and performance considerations when the rotary-vee mechanism is used as an internal combustion (I.C.) heat engine are reviewed. Included is a simplified kinematic analysis and studies of the effects of design parameters on the critical pressures, torques and parasitic losses. A discussion of the principal findings is presented.

  19. Reduction in bacterial counts in infected root canals after rotary or hand nickel-titanium instrumentation--a clinical study.

    Science.gov (United States)

    Rôças, I N; Lima, K C; Siqueira, J F

    2013-07-01

    To compare the antibacterial efficacy of two instrumentation techniques, one using hand nickel-titanium (NiTi) instruments and the other using rotary NiTi instruments, in root canals of teeth with apical periodontitis. Root canals from single-rooted teeth were instrumented using either hand NiTi instruments in the alternated rotation motion technique or rotary BioRaCe instruments. The irrigant used in both groups was 2.5% NaOCl. DNA extracts from samples taken before and after instrumentation were subjected to quantitative analysis by real-time polymerase chain reaction (qPCR). Qualitative analysis was also performed using presence/absence data from culture and qPCR assays. Bacteria were detected in all S1 samples by both methods. In culture analysis, 45% and 35% of the canals were still positive for bacterial presence after hand and rotary NiTi instrumentation, respectively (P > 0.05). Rotary NiTi instrumentation resulted in significantly fewer qPCR-positive cases (60%) than hand NiTi instrumentation (95%) (P = 0.01). Intergroup comparison of quantitative data showed no significant difference between the two techniques. There was no significant difference in bacterial reduction in infected canals after instrumentation using hand or rotary NiTi instruments. In terms of incidence of positive results for bacteria, culture also showed no significant differences between the groups, but the rotary NiTi instrumentation resulted in more negative results in the more sensitive qPCR analysis. © 2013 International Endodontic Journal. Published by John Wiley & Sons Ltd.

  20. Hole history, rotary hole DC-3

    International Nuclear Information System (INIS)

    1977-10-01

    Purpose of hole DC-3 was to drill into the Umtanum basalt flow using both conventional rotary and core drilling methods. The borehole is to be utilized for geophysical logging, future hydrological testing, and the future installation of a borehole laboratory for long-term pressure, seismic, and moisture migration or accumulation recording in the Umtanum basalt flow in support of the Basalt Waste Isolation Program. Hole DC-3 is located east of the 200 West barricaded area on the Hanford reservation

  1. Transient analysis of a variable speed rotary compressor

    International Nuclear Information System (INIS)

    Park, Youn Cheol

    2010-01-01

    A transient simulation model of a rolling piston type rotary compressor is developed to predict the dynamic characteristics of a variable speed compressor. The model is based on the principles of conservation, real gas equations, kinematics of the crankshaft and roller, mass flow loss due to leakage, and heat transfer. For the computer simulation of the compressor, the experimental data were obtained from motor performance tests at various operating frequencies. Using the developed model, re-expansion loss, friction loss, mass flow loss and heat transfer loss is estimated as a function of the crankshaft speed in a variable speed compressor. In addition, the compressor efficiency and energy losses are predicted at various compressor-operating frequencies. Since the transient state of the compressor strongly depends on the system, the developed model is combined with a transient system simulation program to get transient variations of the compression process in the system. Motor efficiency, mechanical efficiency, motor torque and volumetric efficiency are calculated with respect to variation of the driving frequency in a rotary compressor.

  2. Rotary kiln incinerator engineering tests on simulated transuranic wastes from the Idaho National Engineering Laboratory. Final report

    International Nuclear Information System (INIS)

    Pattengill, M.G.; Brunner, F.A.; Fasso, J.L.; Mitchel, S.R.; Praskac, R.T.

    1982-09-01

    Nine rotary kiln incineration tests were performed at Colorado School of Mines Research Institute on simulated transuranic waste materials. The rotary kiln incinerator used as 3 ft ID and 30 ft long and was included in an incineration system that also included an afterburner and a baghouse. The purpose of the incineration test program was to determine the applicability and operating characteristics of the rotary kiln with relation to the complete incineration of the simulated waste materials. The results of the study showed that the rotary kiln did completely incinerate the waste materials. Off-gas determinations showed emission levels of SO 2 , NO/sub x/, H 2 SO 4 , HC1, particulate loading, and hydrocarbons, as well as exhaust gas volume, to be within reasonable controllable ranges in a production operation. Included in the report are the results of materials and energy balances, based upon data collected, and design recommendations based upon the data and upon observations during the incineration operation

  3. CFD analysis of a rotary kiln using for plaster production and discussion of the effects of flue gas recirculation application

    Science.gov (United States)

    Gürtürk, Mert; Oztop, Hakan F.; Pambudi, Nugroho Agung

    2018-04-01

    In this study, the CFD analysis of the rotary kiln is carried out for examining effects of various parameters on energy consumption and efficiency of the rotary kiln. The flue gas recirculation using in many applications is a useful method for combusting of fuel unburned in the flue gas. Also, effects of flue gas recirculation on the combusting of fuel, operating temperature and efficiency of the rotary kiln are discussed in this study. The rotary kiln, which is considered in this study, is used in plaster plant. Two different CFD models were created and these models are compared according to many parameters such as temperature distribution, mixture fraction, the mass fraction of O2, CO, CO and CH4 in the combustion chamber. It is found that the plaster plant has a great potential for an increase in energy efficiency. Results obtained for producers of rotary kiln and burner will be useful for determining better design parameters.

  4. Spiral computed tomography assessment of the efficacy of different rotary versus hand retreatment system

    OpenAIRE

    Neelam Mittal; Jyoti Jain

    2014-01-01

    Aims: The purpose of this study was to evaluate the efficacy of nickel-titanium rotary retreatment systems versus stainless steel hand retreatment system with or without solvent for gutta-percha removal during retreatment. Materials and Methods: Sixty extracted human mandibular molar teeth with single canal in a distal root was prepared with ProTaper rotary nickel-titanium files and obturated with gutta-percha and sealer. The teeth were randomly divided into six groups of 10 specimens in ...

  5. Engineering study on the rotary-vee engine concept

    Science.gov (United States)

    Willis, Edward A.; Bartland, Timothy A.; Beard, John E.

    1989-01-01

    This paper provides a review of the applicable thermodynamic cycle and performance considerations when the rotary-vee mechanism is used as an internal combustion (IC) heat engine. Included is a simplified kinematic analysis and studies of the effects of design parameters on the critical pressures, torques and parasitic losses. A discussion of the principal findings is presented.

  6. A scanning electron microscopic study of smear layer remaining following use of Greater Taper rotary instruments

    Directory of Open Access Journals (Sweden)

    S Soumya

    2011-01-01

    Full Text Available The aim of this in vitro study was to evaluate the smear layer in the root canal following the use of Ni-Ti hand ProTaper, HERO shaper and Twisted rotary instruments. Fifteen freshly extracted single rooted human mandibular premolar teeth were selected. Crowns of all teeth were cut off at the cemento-enamel junction with a carborundum disc. The roots were then randomly divided into three groups of 5 samples each. The working length of all teeth was established by the insertion of an endodontic instrument into the canal until its tip is visible at the apical foramen and then subtracted by 0.5 mm. A sequential crown down technique was carried out in all the three groups as follows: Group-I- Specimens in this group were instrumented with ProTaper Ni-Ti hand instruments. Group-II- Specimens were instrumented with HERO shapers. Group-III - The specimens in this group were instrumented with Twisted rotary instruments. Irrigation was done with 3% NaOCl and 15% EDTA in all the three groups. Teeth were carefully split with hammer and chisel and stored in small labeled bottles containing normal saline until SEM evaluation. Results showed that when comparing ProTaper files, Twisted rotary instruments and HERO shaper instruments, HERO shaper series of rotary instruments showed maximum amount of smear layer followed by the Twisted rotary instruments. Hand instruments produced least amount of smear layer.

  7. Design of a rotary for an uncontrolled multi-leg intersection in Chennai, India

    Science.gov (United States)

    Vasantha Kumar, S.; Gulati, Himanshu; Arora, Shivam

    2017-11-01

    One way to control the traffic at busy intersections is to construct a roundabout or rotary intersection, which is a special type of at-grade intersection, where all converging vehicles are forced to move round a central island in clock-wise direction. The present study aims to design a rotary for an uncontrolled multi leg intersection located in Royapetah in Chennai, India. The intersection has five approach roads with two-way traffic in all the approach roads and there is no signal or traffic police to control the traffic at present and hence experiences traffic chaos during peak hours. In order to design the rotary, it is essential to have the information on traffic volumes coming from the approach roads. For this, a video data collection was carried out for a duration of eight hours from 7.30 am to 11.30 am and from 2.30 pm to 6.30 pm on a typical working day using a handycam from the terrace of an apartment building located near the intersection. During data extraction stage, each 5 min. traffic volume was extracted for all the five classes of vehicles considered and were converted to passenger car units (PCU). The analysis of traffic data showed that during peak hour from 4.45 pm to 5.45 pm, the proportion of weaving traffic, i.e., ratio of sum of crossing streams to the total traffic on the weaving section was found to be 0.81. According to Indian road congress (IRC) guidelines, this proportion can take any value between 0.4 and 1 and in the present study, the calculated value is found to be within the prescribed range. Using the calculated values of average entry width of the rotary and width & length of weaving section, the practical capacity of the rotary was found to be 3020 PCUs which is well above the observed traffic volume of 2665 PCUs.

  8. Deformation and fracture of Mtwo rotary nickel-titanium instruments after clinical use.

    Science.gov (United States)

    Inan, Ugur; Gonulol, Nihan

    2009-10-01

    In recent years, a number of rotary nickel titanium (NiTi) systems have been developed to provide better, faster, and easier cleaning and shaping of the root canal system. Although the NiTi instruments are more flexible than the stainless steel files, the main problem with the rotary NiTi instruments is the failure of the instruments. The aim of this study was to evaluate the deformation and fracture rate of Mtwo rotary nickel-titanium instruments (VDW, Munich, Germany) discarded after routine clinical use. A total of 593 Mtwo rotary NiTi instruments were collected after clinical use from the clinic of endodontics over 12 months. The length of the files was measured using a digital caliper to determine any fracture, and then all the files were evaluated under a stereomicroscope for defects such as unwinding, curving, or bending and fracture. The fracture faces of separated files were also evaluated under a scanning electron microscope. The data were analyzed using a chi-square and z test. A percentage of all files (25.80%) showed defects, and the major defect was fracture (16.02%). The most frequently fractured file was #10.04 (30.39%). Deformations without fracture were mostly observed on #15.05 files (25.47%). A higher rate of deformation was observed for #10.04 and #15.05 files. Therefore, these files should be considered as single-use instruments. Because cyclic fatigue was the cause of 71.58% of the instrument fractures, it is also important not to exceed the maximum number of usage recommended by the manufacturer and discard the instruments on a regular basis.

  9. Smear layer and debris removal using manual Ni-Ti files compared with rotary Protaper Ni- Ti files - An In-Vitro SEM study.

    Science.gov (United States)

    Reddy, J M V Raghavendra; Latha, Prasanna; Gowda, Basavana; Manvikar, Varadendra; Vijayalaxmi, D Benal; Ponangi, Kalyana Chakravarthi

    2014-02-01

    Predictable successful endodontic therapy depends on correct diagnosis, effective cleaning, shaping and disinfection of the root canals and adequate obturation. Irrigation serves as a flush to remove debris, tissue solvent and lubricant from the canal irregularities; however these irregularities can restrict the complete debridement of root canal by mechanical instrumentation.Various types of hand and rotary instruments are used for the preparation of the root canal system to obtain debris free canals. The purpose of this study was to evaluate the amount of smear layer and debris removal on canal walls following the using of manual Nickel-Titanium (NiTi) files compared with rotary ProTaperNiTi files using a Scanning Electron Microscope in two individual groups. A comparative study consisting of 50 subjects randomized into two groups - 25 subjects in Group A (manual) and 25 subjects in Group B (rotary) was undertaken to investigate and compare the effects of smear layer and debris between manual and rotary NiTi instruments. Chi square test was used to find the significance of smear layer and debris removal in the coronal, middle and apical between Group A and Group B. Both systems of Rotary ProTaperNiTi and manual NiTi files used in the present study, did not create completely clean root canals. Manual NiTi files produced significantly less smear layer and debris compared to Rotary ProTaperNiTi instruments. Rotary instruments were less time consuming when compared to manual instruments. Instrument separation was not found to be significant with both the groups. Both systems of Rotary ProTaperNiTi and manual NiTi files used did not produce completely clean root canals. Manual NiTi files produced significantly less smear layer and debris compared to Rotary protaper instruments. How to cite the article: Reddy JM, Latha P, Gowda B, Manvikar V, Vijayalaxmi DB, Ponangi KC. Smear layer and debris removal using manual Ni-Ti files compared with rotary Protaper Ni-Ti files

  10. ROTARY DAY AT THE UNITED NATIONS OFFICE IN GENEVA

    CERN Multimedia

    Staff Association

    2017-01-01

    We have been informed about the Rotary day at the United Nations office in Geneva. Join us on November 10th & 11th, 2017 at the United Nations office Avenue de la Paix 8-14 1211 Geneva, Switzerland   PEACE: MAKING A DIFFERENCE! Conflict and violence displace millions of people each year. Half of those killed in conflict are children, and 90 percent are civilians. We, Rotarians, refuse conflict as a way of life. But how can we contribute to Peace? And what about you? Are you keen on meeting exceptional individuals and exchanging ideas to move forward? Would you like to network and collaborate with Rotarians, Government Representatives, International Civil Servants, Representatives of Nongovernmental Organizations and Liberal Professions, Businessmen/women, and Students to make a difference in Peace? In November 2017, come to Geneva, get involved, and formulate recommendations to the international community. Together, we’ll celebrate Rotary&a...

  11. A Diagnostic System for Speed-Varying Motor Rotary Faults

    Directory of Open Access Journals (Sweden)

    Chwan-Lu Tseng

    2014-01-01

    Full Text Available This study proposed an intelligent rotary fault diagnostic system for motors. A sensorless rotational speed detection method and an improved dynamic structural neural network are used. Moreover, to increase the convergence speed of training, a terminal attractor method and a hybrid discriminant analysis are also adopted. The proposed method can be employed to detect the rotary frequencies of motors with varying speeds and can enhance the discrimination of motor faults. To conduct the experiments, this study used wireless sensor nodes to transmit vibration data and employed MATLAB to write codes for functional modules, including the signal processing, sensorless rotational speed estimation, neural network, and stochastic process control chart. Additionally, Visual Basic software was used to create an integrated human-machine interface. The experimental results regarding the test of equipment faults indicated that the proposed novel diagnostic system can effectively estimate rotational speeds and provide superior ability of motor fault discrimination with fast training convergence.

  12. Results of the 1000 Hour Rotary Microfilter Endurance Test

    International Nuclear Information System (INIS)

    Herman, D.

    2010-01-01

    During operation, a primary concern is lifetime of the mechanical seal. Leakage from main shaft mechanical seal is expected to be first indication of wear on rotary filter but will not be the ultimate failure of the filter. Initial clearance inadequate to support thermal expansion resulted in initial scarring of journal. Tolerances adjusted and no journal issues were found during 1000 hour test. Disassembly and inspection of the rotary joint seals showed no unusual wear. No leakage observed during test. Total operation time over 1500 hours. Test summary successfully demonstrated: (1) Filtration of a 'challenging' SRS simulant up to 15 wt % insoluble solids in a 5.6 M salt simulant; (2) Sludge washing; (3) In-situ acid cleaning with dilute acid; (4) Over 1000 hours of operation on new journal material; and (5) Over 1500 hours of operation on all seals. The filter out lasted: 2 air compressors, 2 power outages (one planned), 2 chillers, 1 fire, 1 electrical breaker and 1 feed pump seal.

  13. Development of a Rotary Microfilter for SRS HLW Applications

    International Nuclear Information System (INIS)

    MICHAEL, POIRIER

    2005-01-01

    The processing rate of Savannah River Site (SRS) high-level waste decontamination processes are limited by the flow rate of the solid-liquid separation. The baseline process, using a 0.1 micron cross-flow filter, produces approximately 0.02 gpm/sq. ft. of filtrate under expected operating conditions. Savannah River National Laboratory (SRNL) personnel identified the rotary microfilter as a technology that could significantly increase filter flux, with throughput improvements of as much as 10X for that specific operation. With funding from the U. S. Department of Energy Office of Cleanup Technology, SRNL personnel are evaluating and developing the rotary microfilter for radioactive service at SRS. This work includes pilot-scale and actual waste testing to evaluate system reliability, the impact of radiation on system components, the filter flux for a variety of waste streams, and relative performance for alternative filter media. Personnel revised the design for the disks and filter unit to make them suitable for high-level radioactive service

  14. Rotary shaft seal

    International Nuclear Information System (INIS)

    Langebrake, C.O.

    1984-01-01

    The invention is a novel rotary shaft seal assembly which provides positive-contact sealing when the shaft is not rotated and which operates with its sealing surfaces separated by a film of compressed ambient gas whose width is independent of the speed of shaft rotation. In a preferred embodiment, the assembly includes a disc affixed to the shaft for rotation therewith. Axially movable, non-rotatable plates respectively supported by sealing bellows are positioned on either side of the disc to be in sealing engagement therewith. Each plate carries piezoelectric transducer elements which are electrically energized at startup to produce films of compressed ambient gas between the confronting surfaces of the plates and the disc. Following shutdown of the shaft, the transducer elements are de-energized. A control circuit responds to incipient rubbing between the plate and either disc by altering the electrical input to the transducer elements to eliminate rubbing

  15. Carbon Fiber Reinforced Carbon Composite Rotary Valve for an Internal Combustion Engine

    Science.gov (United States)

    Northam, G.Burton (Inventor); Ransone, Philip O. (Inventor); Rivers, H. Kevin (Inventor)

    2000-01-01

    Carbon fiber reinforced carbon composite rotary sleeve, and disc valves for internal combustion engines and the like are disclosed. The valves are formed from knitted or braided or wrap-locked carbon fiber shapes. Also disclosed are valves fabricated from woven carbon fibers and from molded carbon matrix material. The valves of the present invention with their very low coefficient of thermal expansion and excellent thermal and self-lubrication properties do not present the sealing and lubrication problems that have prevented rotary sleeve and disc valves from operating efficiently and reliably in the past. Also disclosed are a sealing tang to further improve sealing capabilities and anti-oxidation treatments.

  16. Fluid Dynamics in Rotary Piston Blood Pumps.

    Science.gov (United States)

    Wappenschmidt, Johannes; Sonntag, Simon J; Buesen, Martin; Gross-Hardt, Sascha; Kaufmann, Tim; Schmitz-Rode, Thomas; Autschbach, Ruediger; Goetzenich, Andreas

    2017-03-01

    Mechanical circulatory support can maintain a sufficient blood circulation if the native heart is failing. The first implantable devices were displacement pumps with membranes. They were able to provide a sufficient blood flow, yet, were limited because of size and low durability. Rotary pumps have resolved these technical drawbacks, enabled a growing number of mechanical circulatory support therapy and a safer application. However, clinical complications like gastrointestinal bleeding, aortic insufficiency, thromboembolic complications, and impaired renal function are observed with their application. This is traced back to their working principle with attenuated or non-pulsatile flow and high shear stress. Rotary piston pumps potentially merge the benefits of available pump types and seem to avoid their complications. However, a profound assessment and their development requires the knowledge of the flow characteristics. This study aimed at their investigation. A functional model was manufactured and investigated with particle image velocimetry. Furthermore, a fluid-structure interaction computational simulation was established to extend the laboratory capabilities. The numerical results precisely converged with the laboratory measurements. Thus, the in silico model enabled the investigation of relevant areas like gap flows that were hardly feasible with laboratory means. Moreover, an economic method for the investigation of design variations was established.

  17. Rotary engine performance computer program (RCEMAP and RCEMAPPC): User's guide

    Science.gov (United States)

    Bartrand, Timothy A.; Willis, Edward A.

    1993-01-01

    This report is a user's guide for a computer code that simulates the performance of several rotary combustion engine configurations. It is intended to assist prospective users in getting started with RCEMAP and/or RCEMAPPC. RCEMAP (Rotary Combustion Engine performance MAP generating code) is the mainframe version, while RCEMAPPC is a simplified subset designed for the personal computer, or PC, environment. Both versions are based on an open, zero-dimensional combustion system model for the prediction of instantaneous pressures, temperature, chemical composition and other in-chamber thermodynamic properties. Both versions predict overall engine performance and thermal characteristics, including bmep, bsfc, exhaust gas temperature, average material temperatures, and turbocharger operating conditions. Required inputs include engine geometry, materials, constants for use in the combustion heat release model, and turbomachinery maps. Illustrative examples and sample input files for both versions are included.

  18. Computational experience with a three-dimensional rotary engine combustion model

    Science.gov (United States)

    Raju, M. S.; Willis, E. A.

    1990-04-01

    A new computer code was developed to analyze the chemically reactive flow and spray combustion processes occurring inside a stratified-charge rotary engine. Mathematical and numerical details of the new code were recently described by the present authors. The results are presented of limited, initial computational trials as a first step in a long-term assessment/validation process. The engine configuration studied was chosen to approximate existing rotary engine flow visualization and hot firing test rigs. Typical results include: (1) pressure and temperature histories, (2) torque generated by the nonuniform pressure distribution within the chamber, (3) energy release rates, and (4) various flow-related phenomena. These are discussed and compared with other predictions reported in the literature. The adequacy or need for improvement in the spray/combustion models and the need for incorporating an appropriate turbulence model are also discussed.

  19. CFD modeling using PDF approach for investigating the flame length in rotary kilns

    Science.gov (United States)

    Elattar, H. F.; Specht, E.; Fouda, A.; Bin-Mahfouz, Abdullah S.

    2016-12-01

    Numerical simulations using computational fluid dynamics (CFD) are performed to investigate the flame length characteristics in rotary kilns using probability density function (PDF) approach. A commercial CFD package (ANSYS-Fluent) is employed for this objective. A 2-D axisymmetric model is applied to study the effect of both operating and geometric parameters of rotary kiln on the characteristics of the flame length. Three types of gaseous fuel are used in the present work; methane (CH4), carbon monoxide (CO) and biogas (50 % CH4 + 50 % CO2). Preliminary comparison study of 2-D modeling outputs of free jet flames with available experimental data is carried out to choose and validate the proper turbulence model for the present numerical simulations. The results showed that the excess air number, diameter of kiln air entrance, radiation modeling consideration and fuel type have remarkable effects on the flame length characteristics. Numerical correlations for the rotary kiln flame length are presented in terms of the studied kiln operating and geometric parameters within acceptable error.

  20. Apical extrusion of debris using reciprocating files and rotary ...

    African Journals Online (AJOL)

    Procedure: Sixty extracted human mandibular premolars were used. The root canals were instrumented using reciprocating (WaveOne, Reciproc, SafeSider) or rotary ... and cross‑sections, and kinematics, and this situation may influence the amount of apically extruded debris through the apical foramen.[15]. The aim of this ...

  1. The phenomenon of resilient rotary curvature of hexagon selenium nanothin crystals grate around [001] within the framework of asymmetrical theory of resiliency

    International Nuclear Information System (INIS)

    Malkov, V.B.; Agalakov, S.P.; Malkov, A.V.; Malkov, O.V.; Pushin, V.G.; Shul'gin, B.V.

    2008-01-01

    The research of resilient rotary curvature of hexagon selenium nanothin (80-100 nm) crystals grate the method of translucent electronic microscopy. In view of the fact that reasons of resilient rotary curvature of hexagon selenium nanothin crystals grate around [001] remained not found out, the analysis of models of resilient rotary curvature of hexagon selenium crystals grate is conducted.

  2. A comparative evaluation of the increase in root canal surface area and canal transportation in curved root canals by three rotary systems: A cone-beam computed tomographic study

    Science.gov (United States)

    Prasanthi, Nalam NVD; Rambabu, Tanikonda; Sajjan, Girija S; Varma, K Madhu; Satish, R Kalyan; Padmaja, M

    2016-01-01

    Aim: The aim of this study was to measure the increase in root canal surface area and canal transportation after biomechanical preparation at 1, 3, and 5 mm short of the apex with three different rotary systems in both continuous rotary and reciprocating rotary motions. Materials and Methods: Sixty freshly extracted human mandibular molars with mesial root canal curvatures between 20° and 30° were included in the study. Teeth were randomly distributed into three groups (n = 20). Biomechanical preparations were done in all the mesial canals. In Group 1, instrumentation was done with ProTaper universal rotary files, Group 2, with K3XF rotary files, and Group 3, with LSX rotary files. Each group was further subdivided into subgroups A and B (n = 10) where instrumentation was done by continuous rotary and reciprocating rotary techniques, respectively. Increase in root canal surface area and canal transportation was measured using the preoperative and postoperative cone-beam computed tomography scans. Statistical Analysis: The data were analyzed by one-way ANOVA followed by Tukey pairwise multiple comparison tests. Results: Increase in root canal surface area was significantly more (P 0.05) in increase of root canal surface area and canal transportation between continuous rotary and reciprocating rotary techniques for ProTaper Universal, K3XF and LSX groups. Conclusion: LSX rotary system showed minimal increase of root canal surface area and minimal canal transportation when compared to ProTaper and K3XF rotary systems. PMID:27656062

  3. Satisfaction of undergraduate students at University of Jordan after root canal treatment of posterior teeth using rotary or hand preparation.

    Science.gov (United States)

    Abu-Tahun, Ibrahim; El-Ma'aita, Ahmad; Khraisat, Ameen

    2016-08-01

    The aim of this study was to report the satisfaction of fifth year undergraduate students on the clinical use of rotary endodontic preparation compared with stainless steel standard technique and to evaluate the impact of rotary nickel-titanium instruments on undergraduate teaching. This study was carried out by the fifth year undergraduate students attending peer review sessions as a part of their training program using a questionnaire to assess their satisfaction with these two techniques. The overall results indicated a statistically significant satisfaction of the undergraduate students with the use of the nickel-titanium system (P ProTaper rotary files and the need for undergraduate teaching of rotary nickel-titanium systems in Jordan. © 2015 Australian Society of Endodontology Inc.

  4. Performance of Rotary Cutter Type Breaking Machine for Breakingand Deshelling Cocoa Roasted Beans

    Directory of Open Access Journals (Sweden)

    Sukrisno Widyotomo

    2005-12-01

    Full Text Available Conversion of cocoa beans to chocolate product is, therefore, one of the promising alternatives to increase the value added of dried cocoa beans. On the other hand, the development of chocolate industry requires an appropriate technology that is not available yet for small or medium scale of business. Breaking and deshelling cocoa roasted beans is one important steps in cocoa processing to ascertain good chocolate quality. The aim of this research is to study performance of rotary cutter type breaking machine for breaking and deshelling cocoa roasted beans. Indonesian Coffee and Cocoa Research Institute has designed and tested a rotary cutter type breaking machine for breaking and deshelling cocoa roasted beans. Breaker unit has rotated by ½ HP power, single phase, 110/220 V and 1440 rpm. Transmission system that use for rotating breaker unit is pulley and single V belt. Centrifugal blower as separator unit between cotyledon and shell has specification 0.5 m 3 /min air flow, 780 Pa, 370 W, and 220 V. Field tests showed that the optimum capacity of the machine was 268 kg/h with 500 rpm speed of rotary cutter, 2,8 m/s separator air flow, and power require was 833 W. Percentage product in outlet 1 and 2 were 94.5% and 5.5%. Particle distribution from outlet 1 was 92% as cotyledon, 8% as shell in cotyledon and on outlet 2 was 97% as shell, 3% as cotyledon in shell. Key words:cocoa, breaking, rotary cutter, quality.

  5. Histological analysis of cleaning efficacy of hand and rotary instruments in the apical third of the root canal: A comparative study.

    Science.gov (United States)

    Arya, Ashtha; Bali, Dildeep; Grewal, Mandeep S

    2011-07-01

    To compare the cleaning efficiency of manual and rotary instrumentation in the apical third of the root canal system. In group 1 (n=10), instrumentation was performed with stainless steel K-file; in group 2 (n=10), it was done with hand ProTaper files; and in group 3 (n=10), instrumentation was done with ProTaper rotary. Distilled water was used for irrigation. The apical third was sectioned transversally and histologically processed. The cross sections were examined under optic microscope and debris was measured using Motic software. Instrumentation with stainless steel K-files showed minimum amount of debris, followed by ProTaper hand files, and rotary ProTaper files were least effective with maximum amount of debris; however, there were no significant differences between the three experimental groups. Both the manual and rotary instrumentation are relatively efficient in cleaning the apical third of the root canal system and the choice between manual and rotary instrumentation should depend on case to case basis.

  6. Tunable rotary orbits of matter-wave nonlinear modes in attractive Bose-Einstein condensates

    International Nuclear Information System (INIS)

    He, Y J; Wang, H Z; Malomed, Boris A; Mihalache, Dumitru

    2008-01-01

    We demonstrate that by spatially modulating the Bessel optical lattice where a Bose-Einstein condensate is loaded, we get tunable rotary orbits of nonlinear lattice modes. We show that the radially expanding or shrinking Bessel lattice can drag the nonlinear localized modes to orbits of either larger or smaller radii and the rotary velocity of nonlinear modes can be changed accordingly. The localized modes can even be transferred to the Bessel lattice core when the localized modes' rotations are stopped. Effects beyond the quasi-particle approximation such as destruction of the nonlinear modes by nonadiabatic dragging are also explored

  7. Design Robust Controller for Rotary Kiln

    Directory of Open Access Journals (Sweden)

    Omar D. Hernández-Arboleda

    2013-11-01

    Full Text Available This paper presents the design of a robust controller for a rotary kiln. The designed controller is a combination of a fractional PID and linear quadratic regulator (LQR, these are not used to control the kiln until now, in addition robustness criteria are evaluated (gain margin, phase margin, strength gain, rejecting high frequency noise and sensitivity applied to the entire model (controller-plant, obtaining good results with a frequency range of 0.020 to 90 rad/s, which contributes to the robustness of the system.

  8. Evaluation of the efficacy of rotary vs. hand files in root canal preparation of primary teeth in vitro using CBCT.

    Science.gov (United States)

    Musale, P K; Mujawar, S A V

    2014-04-01

    This in vitro study aimed to evaluate the efficacy of rotary ProFile, ProTaper, Hero Shaper and K-files in shaping ability, cleaning efficacy, preparation time and instrument distortion in primary molars. Sixty extracted primary mandibular second molars were divided into four equal groups: Group I K-file, Group II ProFile, Group III ProTaper file and Group IV Hero Shaper file. The shaping ability was determined by comparing pre- and post-instrumentation CBCT scans and data analysed with SPSS program using the Chi-square test. Cleaning efficacy was evaluated by the degree of India ink removal from the canal walls under stereomicroscopy. Instrumentation times were calculated for each tooth and instrument distortion was visually checked and duly noted. The cleaning efficacy and instrumentation time were determined using ANOVA with Tukey's correction. Instrument distortion was analysed using Chi-square test. The canal taper was significantly more conical for rotary files as compared to K-files with Chi-square test (p < 0.05). Cleaning efficacy of rotary files with average scores (Groups II- 0.68, III- 0.48 and IV- 0.58) was significantly better than K-files (Group I- 0.93) (p < 0.05). Mean instrumentation time with K-file (20.7 min) was significantly higher than rotary files (Groups II 8.9, III 5.6, and IV 8.1 min) (p < 0.05). Instrument distortion was observed in Group I (4.3%), while none of the rotary files were distorted. Rotary files prepared more conical canals in primary teeth than manual instruments. Reduced preparation time with rotary files enhances patient cooperation especially in young children.

  9. Artificial weathering of oils by rotary evaporator

    International Nuclear Information System (INIS)

    Fieldhouse, B.; Hollebone, B.P.; Singh, N.R.; Tong, T.S.; Mullin, J.

    2009-01-01

    Oil weathering has a considerable affect on the behaviour, impact and ultimate fate of an oil spill. As such, efforts have been made to study weathering as a whole using bench-scale procedures. The studies are generally divided into individual processes where the effect of other major processes are introduce as an amended sample input rather than a concurrent process. The weathering process that has the greatest effect immediately following an oil spill is evaporation, particularly for lighter oils. The rotary evaporator apparatus offers a convenient means of producing artificially weathered oil for laboratory studies. This paper reported on a study that examined the representativeness of samples obtained by this method compared to pan evaporation and the impact of changes to the apparatus or method parameters on sample chemistry. Experiments were performed on Alberta Sweet Mixed Blend no. 5 in a rotary evaporator under varying conditions of temperature and air flow at ambient pressure using 2 apparatus. The rate of mass loss increased with temperature and air flow rate as expected, but the quantitative relationships could not be defined from the data due to contributions by other uncontrolled factors. It was concluded that the rotary evaporator is not suited for evaporation rate studies, but rather for producing samples suitable for use in other studies. Chemical analysis showed that the relative abundance distributions of target n-alkane hydrocarbons varied with the degree of weathering of an oil in a consistent manner at ambient pressure, regardless of the temperature, rate of air exchange or other factors related to the apparatus and procedure. The composition of the artificially weathered oil was also consistent with that from an open pan simulation of a weathered oil slick. Loss of water content varied with the conditions of evaporation because of the differential rates of evaporation due to relative humidity considerations. It was concluded that weathering

  10. Static/dynamic fluid-structure interaction analysis for 3-D rotary blade model

    International Nuclear Information System (INIS)

    Kim, Dong Hyun; Kim, Yu Sung; Kim, Dong Man; Park, Kang Kyun

    2009-01-01

    In this study, static/dynamic fluid-structure interaction analyses have been conducted for a 3D rotary blade model like a turbo-machinery or wind turbine blade. Advanced computational analysis system based on Computational Fluid Dynamics (CFD) and Computational Structural Dynamics (CSD) has been developed in order to investigate detailed dynamic responses of rotary type models. Fluid domains are modeled using the computational grid system with local grid deforming techniques. Reynolds-averaged Navier-Stokes equations with various turbulence model are solved for unsteady flow problems of the rotating blade model. Detailed static/dynamic responses and instantaneous pressure contours on the blade surfaces considering flow-separation effects are presented to show the multi-physical phenomenon of the rotating blades.

  11. Comparison of removed dentin thickness with hand and rotary instruments

    Science.gov (United States)

    Shahriari, Shahriar; Abedi, Hasan; Hashemi, Mahdi; Jalalzadeh, Seyed Mohsen

    2009-01-01

    INTRODUCTION: The aim of this study was to evaluate the amount of dentine removed after canal preparation using stainless steel (SS) hand instruments or rotary ProFile instruments. MATERIALS AND METHODS: Thirty-six extracted human teeth with root canal curvatures less than 30º were embedded in clear polyester resin. The roots were cut horizontally at apical 2, 4 and 7 mm. Dentin thickness was measured at each section and the sections were accurately reassembled using a muffle. Root canals were randomly prepared by SS hand instruments or rotary ProFile instruments. Root sections were again separated, and the remaining dentin thickness was measured. Mann-Whitney U and t tests were performed for analytic comparison of the results. RESULTS: The thickness of removed dentin was significantly different between the two used methods (Pinstrumentation group (Protary instrumentation prepares root canals with a greater conservation of tooth structure. PMID:23940489

  12. Development of Motorized Oil Palm Fruit Rotary Digester | Asoiro ...

    African Journals Online (AJOL)

    A motorized oil palm fruit rotary digester comprising of a feed hopper, hammers, axle, screening plate, v-belt, 2hp electric motor, digesting chamber and frame was designed and developed using standard and locally sourced materials. The performance test analysis showed that its throughput capacity is 117.93kg/hr with a ...

  13. Thermo-Mechanical Calculations of Hybrid Rotary Friction Welding at Equal Diameter Copper Bars and Effects of Essential Parameters on Dependent Special Variables

    International Nuclear Information System (INIS)

    Parsa, M. H.; Davari, H.; Hadian, A. M.; Ahmadabadi, M. Nili

    2007-01-01

    Hybrid Rotary Friction Welding is a modified type of common rotary friction welding processes. In this welding method parameters such as pressure, angular velocity and time of welding control temperature, stress, strain and their variations. These dependent factors play an important rule in defining optimum process parameters combinations in order to improve the design and manufacturing of welding machines and quality of welded parts. Thermo-mechanical simulation of friction welding has been carried out and it has been shown that, simulation is an important tool for prediction of generated heat and strain at the weld interface and can be used for prediction of microstructure and evaluation of quality of welds. For simulation of Hybrid Rotary Friction Welding, a commercial finite element program has been used and the effects of pressure and rotary velocity of rotary part on temperature and strain variations have been investigated

  14. Thermo-Mechanical Calculations of Hybrid Rotary Friction Welding at Equal Diameter Copper Bars and Effects of Essential Parameters on Dependent Special Variables

    Science.gov (United States)

    Parsa, M. H.; Davari, H.; Hadian, A. M.; Ahmadabadi, M. Nili

    2007-05-01

    Hybrid Rotary Friction Welding is a modified type of common rotary friction welding processes. In this welding method parameters such as pressure, angular velocity and time of welding control temperature, stress, strain and their variations. These dependent factors play an important rule in defining optimum process parameters combinations in order to improve the design and manufacturing of welding machines and quality of welded parts. Thermo-mechanical simulation of friction welding has been carried out and it has been shown that, simulation is an important tool for prediction of generated heat and strain at the weld interface and can be used for prediction of microstructure and evaluation of quality of welds. For simulation of Hybrid Rotary Friction Welding, a commercial finite element program has been used and the effects of pressure and rotary velocity of rotary part on temperature and strain variations have been investigated.

  15. A rotary multimodal hybrid energy harvesting device powered by human motion

    Science.gov (United States)

    Larkin, Miles R.

    This thesis presents a novel hybrid multimodal energy harvesting device consisting of an unbalanced rotary disk that supports two transduction methods, piezoelectric and electromagnetic. The device generates electrical energy from oscillatory motion either orthogonal or parallel to the rotary axis to power electronic devices. Analytical models of the device were developed, from which numerical simulations were performed for several different generator sizes. Two prototypes, 180 mm and 100 mm in diameter, respectively, were fabricated and characterized experimentally with a modal shaker. The 180 mm prototype generated 120 mW from the electromagnetic system at 5 Hz and 0.8g, and 4.23 mW from the piezoelectric system at 20.2 Hz and 0.4g excitation acceleration. Finally, the power generation capabilities of the two prototypes were compared to other similar devices.

  16. Quantitative control of a rotary carbon nanotube motor under temperature stimulus

    International Nuclear Information System (INIS)

    Cai, Kun; Wan, Jing; Shi, Jiao; Qin, Qing H

    2016-01-01

    Since a double-walled carbon nanotube (DWCNT)-based rotary motor driven by a uniform temperature field was proposed in 2014, how to control quantitatively the rotation of the rotor is still an open question. In this work, we present a mathematical relationship between the rotor’s speed and interaction energy. Essentially, the increment of interaction energy between the rotor and the stator(s) determines the rotor’s rotational speed, whereas the type of radial deviation of an end carbon atom on the stator determines the rotational direction. The rotational speed of the rotor can be specified by adjusting temperature and radial deviation of an end carbon atom on the stator. It is promising for designing a controllable temperature-driven rotary motor based on DWCNTs with length of few nanometers only. (paper)

  17. Control of Rotary Cranes Using Fuzzy Logic

    Directory of Open Access Journals (Sweden)

    Amjed A. Al-mousa

    2003-01-01

    Full Text Available Rotary cranes (tower cranes are common industrial structures that are used in building construction, factories, and harbors. These cranes are usually operated manually. With the size of these cranes becoming larger and the motion expected to be faster, the process of controlling them has become difficult without using automatic control methods. In general, the movement of cranes has no prescribed path. Cranes have to be run under different operating conditions, which makes closed-loop control attractive.

  18. Deciphering Intrinsic Inter-subunit Couplings that Lead to Sequential Hydrolysis of F 1 -ATPase Ring

    Science.gov (United States)

    Dai, Liqiang; Flechsig, Holger; Yu, Jin

    2017-10-01

    The rotary sequential hydrolysis of metabolic machine F1-ATPase is a prominent feature to reveal high coordination among multiple chemical sites on the stator F1 ring, which also contributes to tight coupling between the chemical reaction and central {\\gamma}-shaft rotation. High-speed AFM experiments discovered that the sequential hydrolysis was maintained on the F1 ring even in the absence of the {\\gamma} rotor. To explore how the intrinsic sequential performance arises, we computationally investigated essential inter-subunit couplings on the hexameric ring of mitochondrial and bacterial F1. We first reproduced the sequential hydrolysis schemes as experimentally detected, by simulating tri-site ATP hydrolysis cycles on the F1 ring upon kinetically imposing inter-subunit couplings to substantially promote the hydrolysis products release. We found that it is key for certain ATP binding and hydrolysis events to facilitate the neighbor-site ADP and Pi release to support the sequential hydrolysis. The kinetically feasible couplings were then scrutinized through atomistic molecular dynamics simulations as well as coarse-grained simulations, in which we enforced targeted conformational changes for the ATP binding or hydrolysis. Notably, we detected the asymmetrical neighbor-site opening that would facilitate the ADP release upon the enforced ATP binding, and computationally captured the complete Pi release through charge hopping upon the enforced neighbor-site ATP hydrolysis. The ATP-hydrolysis triggered Pi release revealed in current TMD simulation confirms a recent prediction made from statistical analyses of single molecule experimental data in regard to the role ATP hydrolysis plays. Our studies, therefore, elucidate both the concerted chemical kinetics and underlying structural dynamics of the inter-subunit couplings that lead to the rotary sequential hydrolysis of the F1 ring.

  19. Estimation of instantaneous heat transfer coefficients for a direct-injection stratified-charge rotary engine

    Science.gov (United States)

    Lee, C. M.; Addy, H. E.; Bond, T. H.; Chun, K. S.; Lu, C. Y.

    1987-01-01

    The main objective of this report was to derive equations to estimate heat transfer coefficients in both the combustion chamber and coolant pasage of a rotary engine. This was accomplished by making detailed temperature and pressure measurements in a direct-injection stratified-charge rotary engine under a range of conditions. For each sppecific measurement point, the local physical properties of the fluids were calculated. Then an empirical correlation of the coefficients was derived by using a multiple regression program. This correlation expresses the Nusselt number as a function of the Prandtl number and Reynolds number.

  20. Equivalent Circuit Modeling of a Rotary Piezoelectric Motor

    DEFF Research Database (Denmark)

    El, Ghouti N.; Helbo, Jan

    2000-01-01

    In this paper, an enhanced equivalent circuit model of a rotary traveling wave piezoelectric ultrasonic motor "shinsei type USR60" is derived. The modeling is performed on the basis of an empirical approach combined with the electrical network method and some simplification assumptions about...... of the temperature on the mechanical resonance frequency is considered and thereby integrated in the final model for long term operations....

  1. Development of a novel rotary desiccant cooling cycle with isothermal dehumidification and regenerative evaporative cooling using thermodynamic analysis method

    International Nuclear Information System (INIS)

    La, D.; Li, Y.; Dai, Y.J.; Ge, T.S.; Wang, R.Z.

    2012-01-01

    A novel rotary desiccant cooling cycle is proposed and studied using thermodynamic analysis method. The proposed cycle integrates the technologies of isothermal dehumidification and regenerative evaporative cooling, which are beneficial for irreversibility reduction. Thermodynamic investigation on the basic rotary desiccant cooling cycle shows that the exergy efficiency of the basic cycle is only 8.6%. The processes of desiccant dehumidification and evaporative cooling, which are essentially the basis for rotary desiccant cooling, affect the exergy performance of the cycle greatly and account for about one third of the total exergy destruction. The proposed cycle has potential to improve rotary desiccant cooling technology. It is advantageous in terms of both heat source utilization rate and space cooling capacity. The exergy efficiency of the new cycle is enhanced significantly to 29.1%, which is about three times that of the ventilation cycle, and 60% higher than that of the two-stage rotary desiccant cooling cycle. Furthermore, the regeneration temperature is reduced from 80 °C to about 60 °C. The corresponding specific exergy of the supply air is increased by nearly 30% when compared with the conventional cycles. -- Highlights: ► A novel rotary desiccant cooling cycle is developed using thermodynamic analysis method. ► Isothermal dehumidification and regenerative evaporative cooling have been integrated. ► The cycle is advantageous in terms of both heat source utilization rate and space cooling capacity. ► Cascaded energy utilization is beneficial for cycle performance improvement. ► Upper limits, which will be helpful to practical design and optimization, are obtained.

  2. Comparative evaluation of apically extruded debris during root canal preparation using ProTaper™, Hyflex™ and Waveone™ rotary systems

    Science.gov (United States)

    Surakanti, Jayaprada Reddy; Venkata, Ravi Chandra Polavarapu; Vemisetty, Hari Kumar; Dandolu, Ram Kiran; Jaya, Nagendra Krishna Muppalla; Thota, Shirisha

    2014-01-01

    Background and Aims: Extrusion of any debris during endodontic treatment may potentially cause post-operative complications such as flare-ups. The purpose of this in vitro study was to assess the amount of apically extruded debris during the root canal preparation using rotary and reciprocating nickel-titanium instrumentation systems. Materials and Methods: In this study, 60 human mandibular first premolars were randomly assigned to 3 groups (n = 20 teeth/group). The root canals were instrumented according to the manufacturers’ instructions using the Reciprocating single-file system WaveOne™ (Dentsply Maillefer, Ballaigues, Switzerland) and full-sequence rotary Hyflex CM™ (Coltene Whaledent, Allstetten, Switzerland) and ProTaper™ (Dentsply Maillefer, Ballaigues, Switzerland) instruments. The canals were then irrigated using bidistilled water. The debris that was extruded apically was collected in preweighed eppendorf tubes and assessed with an electronic balance and compared. Statistical Analysis Used: The debris extrusion was compared and statistically analyzed using analysis of variance and the post hoc Student-Newman-Keuls test. Results: The WaveOne™ and ProTaper™ rotary instruments produced significantly more debris compared with Hyflex CM™ rotary instruments (P < 0.05). Conclusions: Under the conditions of this study, all systems that were used resulted in extrusion of apical debris. Full-sequence rotary instrumentation was associated with less debris extrusion compared with the use of reciprocating single-file systems. PMID:24778507

  3. Micro- and macrostructural characterization of polyvinylpirrolidone rotary-spun fibers.

    Science.gov (United States)

    Sebe, István; Kállai-Szabó, Barnabás; Kovács, Krisztián Norbert; Szabadi, Enikő; Zelkó, Romána

    2015-01-01

    The application of high-speed rotary spinning can offer a useful mean for either preparation of fibrous intermediate for conventional dosage forms or drug delivery systems. Polyvinylpyrrolidone (PVP) and poly(vinylpyrrolidone-vinylacetate) (PVP VA) micro- and nanofibers of different polymer concentrations and solvent ratios were prepared with a high-speed rotary spinning technique. In order to study the influence of parameters that enable successful fiber production from polymeric viscous solutions, a complex micro- and macrostructural screening method was implemented. The obtained fiber mats were subjected to detailed morphological analysis using scanning electron microscope (SEM), and rheological measurements while the microstructural changes of fiber samples, based on the free volume changes, was analyzed by positron annihilation lifetime spectroscopy (PALS) and compared with their mechanical characteristics. The plasticizing effect of water tracked by ortho-positronium lifetime changes in relation to the mechanical properties of fibers. A concentration range of polyvinylpyrrolidone solutions was defined for the preparation of fibers of optimum fiber morphology and mechanical properties. The method enabled fiber formulation of advantageous functionality-related properties for further formulation of solid dosage forms.

  4. Results from Testing of Two Rotary Percussive Drilling Systems

    Science.gov (United States)

    Kriechbaum, Kristopher; Brown, Kyle; Cady, Ian; von der Heydt, Max; Klein, Kerry; Kulczycki, Eric; Okon, Avi

    2010-01-01

    The developmental test program for the MSL (Mars Science Laboratory) rotary percussive drill examined the e ect of various drill input parameters on the drill pene- tration rate. Some of the input parameters tested were drill angle with respect to gravity and percussive impact energy. The suite of rocks tested ranged from a high strength basalt to soft Kaolinite clay. We developed a hole start routine to reduce high sideloads from bit walk. The ongoing development test program for the IMSAH (Integrated Mars Sample Acquisition and Handling) rotary percussive corer uses many of the same rocks as the MSL suite. An additional performance parameter is core integrity. The MSL development test drill and the IMSAH test drill use similar hardware to provide rotation and percussion. However, the MSL test drill uses external stabilizers, while the IMSAH test drill does not have external stabilization. In addition the IMSAH drill is a core drill, while the MSL drill uses a solid powdering bit. Results from the testing of these two related drilling systems is examined.

  5. Technological investigation for producing UO2 powder from ADU by using rotary furnace

    International Nuclear Information System (INIS)

    Pham Duc Thai; Ngo Trong Hiep; Dam Van Tien; Vu Quang Chat; Nguyen Duy Lam; Ngo Xuan Hung; Ngo Quang Hien; Tran Duy Hai; Nguyen Van Sinh

    2003-01-01

    Uranium dioxide powder UO 2 is main material for producing UO 2 fuel ceramic pellets. The technical characteristics of UO 2 powder directly affect on mechanical and physical characteristics of UO 2 fuel ceramic pellets. Project titled 'Technological investigation for producing UO 2 powder from ADU by using rotary furnace' with the code number BO/01/03-06 for two years 2001 and 2002, on purpose to step by step perfect the technology and equipments for producing UO 2 powder, that is as nuclear fuel. This UO 2 powder may be good material for producing UO 2 fuel ceramic pellets. The results had been achieved as follows: 1. Study on the perfection of the reduction process U 3 O 8 to UO 2 in the gas mixture of 3H 2 + N 2 in inactive condition. 2. Study, design and production of active device system called rotary furnace for manufacturing UO 2 powder from ADU. 3. Study on 4 steps of technology process: drying, calcination, reduction and stabilization of UO 2 powder in the system of rotary furnace from which obtained UO 2 with technical characteristics meeting basic criteria of UO 2 fuel powder. (author)

  6. Comparative study of root-canal shaping with stainless steel and rotary NiTi files performed by preclinical dental students.

    Science.gov (United States)

    Alrahabi, Mothanna

    2015-01-01

    We evaluated the use of NiTi rotary and stainless steel endodontic instruments for canal shaping by undergraduate students. We also assessed the quality of root canal preparation as well as the occurrence of iatrogenic events during instrumentation. In total, 30 third-year dental students attending Taibah University Dental College prepared 180 simulated canals in resin blocks with NiTi rotary instruments and stainless steel hand files. Superimposed images were prepared to measure the removal of material at different levels from apical termination using the GSA image analysis software. Preparation time, procedural accidents, and canal shape after preparation were analyzed using χ 2 and t-tests. The statistical significance level was set at P instruments and stainless steel files; the former was associated with shorter preparation time, less ledge formation (1.1% vs. 14.4%), and greater instrument fracture (5.56% vs. 1.1%). These results indicate that NiTi rotary instruments result in better canal geometry and cause less canal transportation. Manual instrumentation using stainless steel files is safer than rotary instrumentation for inexperienced students. Intensive preclinical training is a prerequisite for using NiTi rotary instruments. These results prompted us to reconsider theoretical and practical coursework when teaching endodontics.

  7. Lightweight Low Force Rotary Percussive Coring Tool for Planetary Applications, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — Alliance Spacesystems, LLC produced a rotary percussive drill designed for space use under a NASA-funded Mars Instrument Development Program (MIDP) project -- the...

  8. Analysis of kinematic, kinetic and electromyographic patterns during root canal preparation with rotary and manual instruments

    Science.gov (United States)

    PASTERNAK-JÚNIOR, Braulio; de SOUSA NETO, Manoel Damião; DIONÍSIO, Valdeci Carlos; PÉCORA, Jesus Djalma; SILVA, Ricardo Gariba

    2012-01-01

    Objective This study assessed the muscular activity during root canal preparation through kinematics, kinetics, and electromyography (EMG). Material and Methods The operators prepared one canal with RaCe rotary instruments and another with Flexo-files. The kinematics of the major joints was reconstructed using an optoelectronic system and electromyographic responses of the flexor carpi radialis, extensor carpi radialis, brachioradialis, biceps brachii, triceps brachii, middle deltoid, and upper trapezius were recorded. The joint torques of the shoulder, elbow and wrist were calculated using inverse dynamics. In the kinematic analysis, angular movements of the wrist and elbow were classified as low risk factors for work-related musculoskeletal disorders. With respect to the shoulder, the classification was medium-risk. Results There was no significant difference revealed by the kinetic reports. The EMG results showed that for the middle deltoid and upper trapezius the rotary instrumentation elicited higher values. The flexor carpi radialis and extensor carpi radialis, as well as the brachioradialis showed a higher value with the manual method. Conclusion The muscular recruitment for accomplishment of articular movements for root canal preparation with either the rotary or manual techniques is distinct. Nevertheless, the rotary instrument presented less difficulty in the generation of the joint torque in each articulation, thus, presenting a greater uniformity of joint torques. PMID:22437679

  9. Implicit Geometry Meshing for the simulation of Rotary Friction Welding

    Science.gov (United States)

    Schmicker, D.; Persson, P.-O.; Strackeljan, J.

    2014-08-01

    The simulation of Rotary Friction Welding (RFW) is a challenging task, since it states a coupled problem of phenomena like large plastic deformations, heat flux, contact and friction. In particular the mesh generation and its restoration when using a Lagrangian description of motion is of significant severity. In this regard Implicit Geometry Meshing (IGM) algorithms are promising alternatives to the more conventional explicit methods. Because of the implicit description of the geometry during remeshing, the IGM procedure turns out to be highly robust and generates spatial discretizations of high quality regardless of the complexity of the flash shape and its inclusions. A model for efficient RFW simulation is presented, which is based on a Carreau fluid law, an Augmented Lagrange approach in mapping the incompressible deformations, a penalty contact approach, a fully regularized Coulomb-/fluid friction law and a hybrid time integration strategy. The implementation of the IGM algorithm using 6-node triangular finite elements is described in detail. The techniques are demonstrated on a fairly complex friction welding problem, demonstrating the performance and the potentials of the proposed method. The techniques are general and straight-forward to implement, and offer the potential of successful adoption to a wide range of other engineering problems.

  10. Rotary Bed Reactor for Chemical-Looping Combustion with Carbon Capture. Part 1: Reactor Design and Model Development

    KAUST Repository

    Zhao, Zhenlong

    2013-01-17

    Chemical-looping combustion (CLC) is a novel and promising technology for power generation with inherent CO2 capture. Currently, almost all of the research has been focused on developing CLC-based interconnected fluidized-bed reactors. In this two-part series, a new rotary reactor concept for gas-fueled CLC is proposed and analyzed. In part 1, the detailed configuration of the rotary reactor is described. In the reactor, a solid wheel rotates between the fuel and air streams at the reactor inlet and exit. Two purging sectors are used to avoid the mixing between the fuel stream and the air stream. The rotary wheel consists of a large number of channels with copper oxide coated on the inner surface of the channels. The support material is boron nitride, which has high specific heat and thermal conductivity. Gas flows through the reactor at elevated pressure, and it is heated to a high temperature by fuel combustion. Typical design parameters for a thermal capacity of 1 MW have been proposed, and a simplified model is developed to predict the performances of the reactor. The potential drawbacks of the rotary reactor are also discussed. © 2012 American Chemical Society.

  11. Rotary Drill Operator. Open Pit Mining Job Training Series.

    Science.gov (United States)

    Savilow, Bill

    This training outline for rotary drill operators, one in a series of eight outlines, is designed primarily for company training foremen or supervisors and for trainers to use as an industry-wide guideline for heavy equipment operator training in open pit mining in British Columbia. Intended as a guide for preparation of lesson plans both for…

  12. Ameerika Rotary klubi toetab Maarja küla miljoni krooniga / Kristel Rõss

    Index Scriptorium Estoniae

    Rõss, Kristel, 1967-

    2003-01-01

    Taevaskotta Haavassaarde rajatav Maarja küla oli nädalavahetusel eriliselt rahvarohke, sest puuetega noorte kodu ligi miljoni krooniga toetada lubanud Rotary klubi liikmed Atlantast istutasid Eestimaa mulda tammepuid

  13. A rotary permanent magnet magnetic refrigerator based on AMR cycle

    International Nuclear Information System (INIS)

    Aprea, C.; Cardillo, G.; Greco, A.; Maiorino, A.; Masselli, C.

    2016-01-01

    Magnetic refrigeration is an emerging, environment-friendly technology based on a magnetic solid that acts as a refrigerant by magneto-caloric effect (MCE). The reference cycle for magnetic refrigeration is AMR (Active Magnetic Regenerative refrigeration). In order to demonstrate the potential of magnetic refrigeration to provide useful cooling in the near room temperature range, a novel Rotary Permanent Magnet Magnetic Refrigerator (RPMMR) is described in this paper. Gadolinium has been selected as magnetic refrigerant and demineralized water has been employed as regenerating fluid. The total mass of gadolinium (1.20 kg), shaped as packed bed spheres, is housed in 8 regenerators. A magnetic system, based on a double U configuration of permanent magnets, provides a magnetic flux density of 1.25 T with an air gap of 43 mm. A rotary vane pump forces the regenerating fluid through the regenerators. The operational principle of the magnetic refrigerator and initial experimental results are reported and analyzed.

  14. A Novel Rotary Piezoelectric Motor Using First Bending Hybrid Transducers

    Directory of Open Access Journals (Sweden)

    Yingxiang Liu

    2015-08-01

    Full Text Available We report a novel rotary piezoelectric motor using bending transducers in this work. Three transducers are used to drive a disk-shaped rotor together by the elliptical movements of their driving tips; these motions are produced by the hybrid of two first bending vibration modes. The proposed piezoelectric transducer has a simple structure as it only contains an aluminum alloy beam and four pieces of PZT plates. Symmetrical structure is the only necessary condition in the design process as it will ensure the resonance frequencies of the two orthogonal first bending modes are equal. Transducers with first bending resonance frequency of about 53 kHz were fabricated and assembled into a rotary motor. The proposed motor exhibits good performance on speed and torque control. Under a working frequency of 53.2 kHz, the maximum no-load speed and the maximum torque of the prototype are tested to be 53.3 rpm and of 27 mN·m.

  15. Assessment of the role of cross section on fatigue resistance of rotary files when used in reciprocation.

    Science.gov (United States)

    Sekar, Vadhana; Kumar, Ranjith; Nandini, Suresh; Ballal, Suma; Velmurugan, Natanasabapathy

    2016-01-01

    The purpose of this study was to assess the role of cross section on cyclic fatigue resistance of One Shape, Revo-S SU, and Mtwo rotary files in continuous rotation and reciprocating motion in dynamic testing model. A total of 90 new rotary One Shape, Revo-S SU, and Mtwo files (ISO size 25, taper 0.06, length 25 mm) were subjected to continuous rotation or reciprocating motion. A cyclic fatigue testing device was fabricated with 60° angle of curvature and 5 mm radius. The dynamic testing of these files was performed using an electric motor which permitted the reproduction of pecking motion. All instruments were rotated or reciprocated until fracture occurred. The time taken for each instrument to fracture was recorded. All the fractured files were analyzed under a scanning electron microscope (SEM) to detect the mode of fracture. Statistical analysis was performed using one-way ANOVA, followed by Tukey's honestly significant difference post hoc test. The time taken for instruments in reciprocating motion to fail under cyclic loading was significantly longer when compared with groups in continuous rotary motion. There was a statistically significant difference between Mtwo rotary and the other two groups in both continuous and reciprocating motion. One Shape rotary files recorded significantly longer duration to fracture resistance when compared with Revo-S SU files in both continuous and reciprocating motion. SEM observations showed that the instruments of all groups had undergone a ductile mode of fracture. Reciprocating motion improved the cyclic fatigue resistance of all tested groups.

  16. Shaping ability of nickel-titanium rotary instruments in curved root canals.

    Science.gov (United States)

    Talati, Ali; Moradi, Saeed; Forghani, Maryam; Monajemzadeh, Ali

    2013-01-01

    Disinfection and subsequent obturation of the root canal space require adequate mechanical enlargement of the canals. The purpose of this in vitro study was to compare the shaping ability of Mtwo, RaCe and Medin rotary instruments during the preparation of curved root canals. Sixty mesiobuccal root canals of mandibular molars with severe curvatures between 25-35(°) and radius of 4-9 mm were randomly divided into three groups of 20 canals each. Using pre- and post-instrumentation radiographs, straightening of the canal and the apical transportation were determined with AutoCAD software. The data were analyzed using Chi square, analysis of variance, and post-hoc tests and the significance level was set at P0.05). Under the conditions of this in vitro study, Mtwo instruments seemed superior to the two other rotary instruments.

  17. Mixing large and small particles in a pilot scale rotary kiln

    DEFF Research Database (Denmark)

    Nielsen, Anders Rooma; Aniol, Rasmus Wochnik; Larsen, Morten Boberg

    2011-01-01

    The mixing of solid alternative fuel particles in cement raw materials was studied experimentally by visual observation in a pilot scale rotary kiln. Fuel particles were placed on top of the raw material bed prior to the experiment. The percentage of particles visible above the bed as a function...... of time was evaluated with the bed predominantly in the rolling bed mode. Experiments were conducted to investigate the effects of fuel particle size and shape, fuel particle density, rotary kiln fill degree and rotational speed. Large fuel particles and low-density fuel particles appeared more on top...... of the bed than smaller particles and high-density fuel particles. Fuel particle dimensions and sphericity were important parameters for the percentage of visible particles. Increasing bed fill degree and/or increasing rotational speed decreased the percentage of particles visible on top of the bed...

  18. RMs1: qualification results of the rotary miniature Stirling cryocooler at Thales Cryogenics

    Science.gov (United States)

    Martin, Jean-Yves; Seguineau, Cédric; Van-Acker, Sébastien; Sacau, Mikel; Le Bordays, Julien; Etchanchu, Thierry; Vasse, Christophe; Abadie, Christian; Laplagne, Gilles; Benschop, Tonny

    2017-05-01

    The trend for miniaturized Integrated Dewar and Cooler Assemblies (IDCA) has been confirmed over the past few years with several mentions of a new generation of IR detector working at High Operating Temperature (HOT). This key technology enables the use of cryocooler with reduced needs of cryogenics power. As a consequence, miniaturized IDCA are the combination of a HOT IR detector coupled with a low-size, low-weight and low-power (SWaP) cryocooler. Thales Cryogenics has developed his own line of SWaP products. Qualification results on linear solution where shown last year. The current paper focuses on the latest results obtained on RMs1 prototypes, the new rotary SWaP cryocooler from Thales Cryogenics. Cryogenic performances and induced vibrations are presented. In a second part, progress is discussed on compactness and weight on one side, and on power consumption on the other side. It shows how the trade-off made between weight and power consumption could lead to an optimized solution at system level. At least, an update is made on the qualification status.

  19. DEVELOPMENT OF A ROTARY MICROFILTER FOR RADIOACTIVE WASTE APPLICATIONS

    International Nuclear Information System (INIS)

    Poirier, M; David Herman, D; Samuel Fink, S

    2008-01-01

    The processing rate of Savannah River Site (SRS) high-level waste decontamination processes are limited by the flow rate of the solid-liquid separation. The baseline process, using a 0.1 micron cross-flow filter, produces ∼0.02 gpm/sq. ft. of filtrate under expected operating conditions. Savannah River National Laboratory (SRNL) demonstrated significantly higher filter flux for actual waste samples using a small-scale rotary filter. With funding from the U. S. Department of Energy Office of Cleanup Technology, SRNL personnel are evaluating and developing the rotary microfilter for radioactive service at SRS. The authors improved the design for the disks and filter unit to make them suitable for high-level radioactive service. They procured two units using the new design, tested them with simulated SRS wastes, and evaluated the operation of the units. Work to date provides the following conclusions and program status: (1) The authors modified the design of the filter disks to remove epoxy and Ryton(reg s ign). The new design includes welding both stainless steel and ceramic coated stainless steel filter media to a stainless steel support plate. The welded disks were tested in the full-scale unit. They showed good reliability and met filtrate quality requirements. (2) The authors modified the design of the unit, making installation and removal easier. The new design uses a modular, one-piece filter stack that is removed simply by disassembly of a flange on the upper (inlet) side of the filter housing. All seals and rotary unions are contained within the removable stack. (3) While it is extremely difficult to predict the life of the seal, the vendor representative indicates a minimum of one year in present service conditions is reasonable. Changing the seal face material from silicon-carbide to a graphite-impregnated silicon-carbide is expected to double the life of the seal. Replacement of the current seal with an air seal could increase the lifetime to 5 years and

  20. A reversible, unidirectional molecular rotary motor driven by chemical energy

    NARCIS (Netherlands)

    Fletcher, SP; Dumur, F; Pollard, MM; Feringa, BL

    2005-01-01

    With the long-term goal of producing nanometer-scale machines, we describe here the unidirectional rotary motion of a synthetic molecular structure fueled by chemical conversions. The basis of the rotation is the movement,of a phenyl rotor relative to a naphthyl stator about a single bond axle. The

  1. Numerical study on oil supply system of a rotary compressor

    International Nuclear Information System (INIS)

    Wu, Jianhua; Wang, Gang

    2013-01-01

    The oil supply system is a crucial reliability issue for rotary compressors. This paper provides a general method for analyzing the oil supply system of a rotary compressor by using computational fluid dynamics (CFD). The process includes establishing the physical model, dividing computational grid, setting boundary conditions, calculating leakage rates through the roller end clearances, translating the dynamic issue into the static issue and so on. Validation of the rationality of the oil supply system model has been made by the measurement of the main bearing oil flow rates. The effects of operating conditions of the compressor, the oil level height of the oil sump and the main design parameters of the oil supply system on the oil supply characteristics are analyzed by numerical simulation. It is found that the main bearing oil flow rate varies circularly along with the rotation of the shaft. The shape and inclination angle of the spiral groove also influence the main bearing oil flow rate. The oil leakage rates through the roller end clearances depend largely on the operating conditions. In addition, the oil level height of the oil sump has a huge effect on the total oil flow rate. -- Highlights: • A CFD method for analyzing the oil supply system of rotary compressor is presented. • Leakage through the roller end clearances depends on the operating condition. • Groove shape and inclination angle are the main design parameters of spiral grooves. • A parabolic interface of oil and gas can be formed in the gallery of the shaft. • Single-flow model and steady solver can be applied to the oil supply system

  2. Operability test report for rotary mode core sampling system number 3

    International Nuclear Information System (INIS)

    Corbett, J.E.

    1996-01-01

    This report documents the successful completion of operability testing for the Rotary Mode Core Sampling (RMCS) system number-sign 3. The Report includes the test procedure (WHC-SD-WM-OTP-174), exception resolutions, data sheets, and a test report summary

  3. Efficacy of two rotary retreatment systems in removing Gutta-percha and sealer during endodontic retreatment with or without solvent: A comparative in vitro study.

    Science.gov (United States)

    Bhagavaldas, Moushmi Chalakkarayil; Diwan, Abhinav; Kusumvalli, S; Pasha, Shiraz; Devale, Madhuri; Chava, Deepak Chowdary

    2017-01-01

    The aim of this in vitro study was to compare the efficacy of two retreatment rotary systems in the removal of Gutta-percha (GP) and sealer from the root canal walls with or without solvent. Forty-eight extracted human mandibular first premolars were prepared and obturated with GP and AH Plus sealer. Samples were then randomly divided into four groups. Group I was retreated with MtwoR rotary system without solvent, Group II was retreated with MtwoR rotary system with Endosolv R as the solvent, Group III with D-RaCe rotary system without solvent, and Group IV with D-RaCe rotary system and Endosolv R solvent. The cleanliness of canal walls was determined by stereomicroscope (×20) and AutoCAD software. Kruskal-Wallis test and Mann-Whitney U-test were used to compare the data. Results showed that none of the retreatment systems used in this study was able to completely remove the root canal filling material. D-RaCe with or without solvent showed significantly ( P > 0.05) less filling material at all levels compared to MtwoR with/without solvent. Within the limitation of the current study, D-RaCe rotary retreatment system is more effective in removing filling material from root canal walls when compared to MtwoR rotary retreatment system.

  4. Devolatilization and Combustion of Tire Rubber and Pine Wood in a Pilot Scale Rotary Kiln

    DEFF Research Database (Denmark)

    Nielsen, Anders R.; Larsen, Morten B.; Glarborg, Peter

    2012-01-01

    Cement production is highly energy intensive and requires large quantities of fuels. For both economical and environmental reasons, there is an increasing tendency for utilization of alternative fuels in the cement industry, examples being tire derived fuels, waste wood, or different types...... of industrial waste. In this study, devolatilization and combustion of large particles of tire rubber and pine wood with equivalent diameters of 10 mm to 26 mm are investigated in a pilot scale rotary kiln able to simulate the process conditions present in the material inlet end of cement rotary kilns...

  5. Cyclic fatigue resistance, torsional resistance, and metallurgical characteristics of M3 Rotary and M3 Pro Gold NiTi files

    Science.gov (United States)

    2018-01-01

    Objectives To evaluate the mechanical properties and metallurgical characteristics of the M3 Rotary and M3 Pro Gold files (United Dental). Materials and Methods One hundred and sixty new M3 Rotary and M3 Pro Gold files (sizes 20/0.04 and 25/0.04) were used. Torque and angle of rotation at failure (n = 20) were measured according to ISO 3630-1. Cyclic fatigue resistance was tested by measuring the number of cycles to failure in an artificial stainless steel canal (60° angle of curvature and a 5-mm radius). The metallurgical characteristics were investigated by differential scanning calorimetry. Data were analyzed using analysis of variance and the Student-Newman-Keuls test. Results Comparing the same size of the 2 different instruments, cyclic fatigue resistance was significantly higher in the M3 Pro Gold files than in the M3 Rotary files (p Rotary files showed 1 small peak on the heating curve and 1 small peak on the cooling curve. Conclusions The M3 Pro Gold files showed greater flexibility and angular rotation than the M3 Rotary files, without decrement of their torque resistance. The superior flexibility of M3 Pro Gold files can be attributed to their martensite phase. PMID:29765904

  6. Incidence of apical root cracks and apical dentinal detachments after canal preparation with hand and rotary files at different instrumentation lengths.

    Science.gov (United States)

    Liu, Rui; Kaiwar, Anjali; Shemesh, Hagay; Wesselink, Paul R; Hou, Benxiang; Wu, Min-Kai

    2013-01-01

    The aim of this study was to compare the incidence of apical root cracks and dentinal detachments after canal preparation with hand and rotary files at different instrumentation lengths. Two hundred forty mandibular incisors were mounted in resin blocks with simulated periodontal ligaments, and the apex was exposed. The root canals were instrumented with rotary and hand files, namely K3, ProTaper, and nickel-titanium Flex K files to the major apical foramen (AF), short AF, or beyond AF. Digital images of the apical surface of every tooth were taken during the apical enlargement at each file change. Development of dentinal defects was determined by comparing these images with the baseline image. Multinomial logistic regression test was performed to identify influencing factors. Apical crack developed in 1 of 80 teeth (1.3%) with hand files and 31 of 160 teeth (19.4%) with rotary files. Apical dentinal detachment developed in 2 of 80 teeth (2.5%) with hand files and 35 of 160 teeth (21.9%) with rotary files. Instrumentation with rotary files terminated 2 mm short of AF and did not cause any cracks. Significantly less cracks and detachments occurred when instrumentation with rotary files was terminated short of AF, as compared with that terminated at or beyond AF (P hand instruments; instrumentation short of AF reduced the risk of dentinal defects. Copyright © 2013 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  7. In vitro evaluation of the effectiveness of ProTaper universal rotary retreatment system for gutta-percha removal with or without a solvent.

    Science.gov (United States)

    Takahashi, Cristiane Midori; Cunha, Rodrigo Sanches; de Martin, Alexandre Sigrist; Fontana, Carlos Eduardo; Silveira, Cláudia Fernandes M; da Silveira Bueno, Carlos Eduardo

    2009-11-01

    Effective removal of gutta-percha in endodontic retreatment is a significant factor to ensure a favorable outcome from failed procedures. The purpose of this study was to evaluate the efficacy of a nickel-titanium rotary instrument system with or without a solvent versus stainless steel hand files for gutta-percha removal. Forty extracted human maxillary anterior teeth were prepared and filled. They were divided into 4 groups: Gates-Glidden and K-files, Gates-Glidden and K-files with chloroform, ProTaper Universal rotary retreatment system, and ProTaper Universal rotary retreatment system with chloroform. The operating time was recorded. The teeth were longitudinally sectioned and photographed. The images were analyzed and the filling remnants were quantified by using the IMAGE TOOL software. With Kruskall-Wallis test, statistical analysis showed that there was no significant difference between the techniques in regard to the amount of the endodontic filling remnants (P ProTaper Universal rotary retreatment system was faster than the hand files (P ProTaper Universal rotary retreatment system without chloroform was faster.

  8. Rotary endodontics in primary teeth – A review

    OpenAIRE

    Sageena George; S. Anandaraj; Jyoti S. Issac; Sheen A. John; Anoop Harris

    2016-01-01

    Endodontic treatment in primary teeth can be challenging and time consuming, especially during canal preparation, which is considered one of the most important steps in root canal therapy. The conventional instrumentation technique for primary teeth remains the “gold-standard” over hand instrumentation, which makes procedures much more time consuming and adversely affects both clinicians and patients. Recently nickel–titanium (Ni–Ti) rotary files have been developed for use in pediatric endod...

  9. Volumetric analysis of hand, reciprocating and rotary instrumentation techniques in primary molars using spiral computed tomography: An in vitro comparative study.

    Science.gov (United States)

    Jeevanandan, Ganesh; Thomas, Eapen

    2018-01-01

    This present study was conducted to analyze the volumetric change in the root canal space and instrumentation time between hand files, hand files in reciprocating motion, and three rotary files in primary molars. One hundred primary mandibular molars were randomly allotted to one of the five groups. Instrumentation was done using Group I; nickel-titanium (Ni-Ti) hand file, Group II; Ni-Ti hand files in reciprocating motion, Group III; Race rotary files, Group IV; prodesign pediatric rotary files, and Group V; ProTaper rotary files. The mean volumetric changes were assessed using pre- and post-operative spiral computed tomography scans. Instrumentation time was recorded. Statistical analysis to access intergroup comparison for mean canal volume and instrumentation time was done using Bonferroni-adjusted Mann-Whitney test and Mann-Whitney test, respectively. Intergroup comparison of mean canal volume showed statistically significant difference between Groups II versus IV, Groups III versus V, and Groups IV versus V. Intergroup comparison of mean instrumentation time showed statistically significant difference among all the groups except Groups IV versus V. Among the various instrumentation techniques available, rotary instrumentation is the considered to be the better instrumentation technique for canal preparation in primary teeth.

  10. Analysis of kinematic, kinetic and electromyographic patterns during root canal preparation with rotary and manual instruments

    Directory of Open Access Journals (Sweden)

    Braulio Pasternak-Júnior

    2012-02-01

    Full Text Available OBJECTIVE: This study assessed the muscular activity during root canal preparation through kinematics, kinetics, and electromyography (EMG. MATERIAL AND METHODS: The operators prepared one canal with RaCe rotary instruments and another with Flexo-files. The kinematics of the major joints was reconstructed using an optoelectronic system and electromyographic responses of the flexor carpi radialis, extensor carpi radialis, brachioradialis, biceps brachii, triceps brachii, middle deltoid, and upper trapezius were recorded. The joint torques of the shoulder, elbow and wrist were calculated using inverse dynamics. In the kinematic analysis, angular movements of the wrist and elbow were classified as low risk factors for work-related musculoskeletal disorders. With respect to the shoulder, the classification was medium-risk. RESULTS: There was no significant difference revealed by the kinetic reports. The EMG results showed that for the middle deltoid and upper trapezius the rotary instrumentation elicited higher values. The flexor carpi radialis and extensor carpi radialis, as well as the brachioradialis showed a higher value with the manual method. CONCLUSION: The muscular recruitment for accomplishment of articular movements for root canal preparation with either the rotary or manual techniques is distinct. Nevertheless, the rotary instrument presented less difficulty in the generation of the joint torque in each articulation, thus, presenting a greater uniformity of joint torques.

  11. A new concept in rotary shaft seal lubrication : viscoelastohydrodynamic (VEHD) lubrication

    NARCIS (Netherlands)

    Leeuwen, van H.J.; Stakenborg, M.J.L.; Dowson, D.; Taylor, C.M.; Godet, M.

    1991-01-01

    In practice rotary shaft seals will experience a small-amplitude dynamic excitation. It is shown that under periodic excitation circumferentially nonuniform clearances develop due to viscous seal material behaviour. The nearby fluid will fill these gaps, so entrainment and squeeze effects can

  12. Modal analysis and modeling of a frictionless electrostatic rotary stepper micromotor

    NARCIS (Netherlands)

    Stranczl, M.; Sarajlic, Edin; Krijnen, Gijsbertus J.M.; Fujita, H.; Gijs, M.A.M.; Yamahata, C.

    2011-01-01

    We present the design, modeling and characterization of a 3-phase electrostatic rotary stepper micromotor. The proposed motor is a monolithic device fabricated using silicon-on-insulator (SOI) technology. The rotor is suspended with a frictionless flexural pivot bearing and reaches an unprecedented

  13. A geometrical optimization of a magneto-rheological rotary brake in a prosthetic knee

    International Nuclear Information System (INIS)

    Gudmundsson, K H; Jonsdottir, F; Thorsteinsson, F

    2010-01-01

    Magneto-rheological (MR) fluids have been successfully introduced to prosthetic devices. One such device is a biomechanical prosthetic knee that uses MR fluids to actively control its rotary stiffness. The brake is rotational, utilizing the MR fluid in shear mode. In this study, the geometrical design of the MR brake is addressed. This includes the design of the magnetic circuit and the geometry of the fluid chamber. Mathematical models are presented that describe the rotary torque of the brake. A novel perfluorinated polyether (PFPE)-based MR fluid is introduced, whose properties are tailored for the prosthetic knee. On-state and off-state rheological measurements of the MR fluid are presented. The finite element method is used to evaluate the magnetic flux density in the MR fluid. The design is formulated as an optimization problem, aiming to maximize the braking torque. A parametric study is carried out for several design parameters. Subsequently, a multi-objective optimization problem is defined that considers three design objectives: the field-induced braking torque, the off-state rotary stiffness and the weight of the brake. Trade-offs between the three design objectives are investigated which provides a basis for informed design decisions on furthering the success of the MR prosthetic knee

  14. PERANCANGAN ULANG ALAT PENGERING BIJI KAKAO TIPE ROTARI SEDERHANA PADA USAHA MANDIRI DI DESA WIYONO KABUPATEN PESAWARAN

    Directory of Open Access Journals (Sweden)

    Ahmad Yudi Eka Risano

    2017-12-01

    Full Text Available Penelitian ini dilakukan pada alat pengering biji kakao untuk proses pengeringan biji kakao milik Usaha Mandiri di Desa Wiyono, Kabupaten Pesawaran. Penelitian ini bertujuan untuk merancang ulang alat pengering biji kakao tipe rotari sederhana agar proses pengeringan lebih efektif dan didapat kualitas hasil pengeringan biji kakao lebih baik. Perhitungan yang dilakukan meliputi dimensi alat pengering, termal yang terjadi pada alat pengering, dan kebutuhan bahan bakar pada alat pengering biji kakao tipe rotari sederhana, serta dilakukan simulasi pada model alat pengering biji kakao tipe rotari sederhana yang telah dirancang menggunakan Software Autodesk CFD untuk mengetahui sebaran suhu pada model alat pengering yang telah dirancang.  Dari hasil penelitian yang telah dilakukan alat pengering biji kakao tipe rotari sederhana ini memiliki dimensi ruang pengering dengan diameter 90 cm, panjang 108 cm, dan tebal 1,2 mm. sebaran suhu pada ruang pengering sebesar 65,06oC , kalor yang dibutuhkan untuk proses pengeringan biji kakao sebesar 1028906,047 KJ, waktu yang dibutuhkan untuk proses pengeringan ± 8 jam 14 menit dan bahan bakar yang dibutuhkan untuk proses pengeringan sebanyak 302,62 kg atau 0,30260 kubik serta sebaran suhu rata-rata hasil simulasi menggunkan Software Autodesk CFD sebesar 63,5116oC.  Kata Kunci: kakao, pengeringan, Autodesk CFD, suhu

  15. A new type of Na(+-driven ATP synthase membrane rotor with a two-carboxylate ion-coupling motif.

    Directory of Open Access Journals (Sweden)

    Sarah Schulz

    Full Text Available The anaerobic bacterium Fusobacterium nucleatum uses glutamate decarboxylation to generate a transmembrane gradient of Na⁺. Here, we demonstrate that this ion-motive force is directly coupled to ATP synthesis, via an F₁F₀-ATP synthase with a novel Na⁺ recognition motif, shared by other human pathogens. Molecular modeling and free-energy simulations of the rotary element of the enzyme, the c-ring, indicate Na⁺ specificity in physiological settings. Consistently, activity measurements showed Na⁺ stimulation of the enzyme, either membrane-embedded or isolated, and ATP synthesis was sensitive to the Na⁺ ionophore monensin. Furthermore, Na⁺ has a protective effect against inhibitors targeting the ion-binding sites, both in the complete ATP synthase and the isolated c-ring. Definitive evidence of Na⁺ coupling is provided by two identical crystal structures of the c₁₁ ring, solved by X-ray crystallography at 2.2 and 2.6 Å resolution, at pH 5.3 and 8.7, respectively. Na⁺ ions occupy all binding sites, each coordinated by four amino acids and a water molecule. Intriguingly, two carboxylates instead of one mediate ion binding. Simulations and experiments demonstrate that this motif implies that a proton is concurrently bound to all sites, although Na⁺ alone drives the rotary mechanism. The structure thus reveals a new mode of ion coupling in ATP synthases and provides a basis for drug-design efforts against this opportunistic pathogen.

  16. Development of the cryo-rotary joint for a HTS synchronous motor with Gd-bulk HTS field-pole magnets

    International Nuclear Information System (INIS)

    Miki, M; Felder, B; Tsuzuki, K; Izumi, M; Hayakawa, H

    2010-01-01

    We have studied a prototype of an axial-gap type synchronous motor with Gd-bulk HTS field-pole magnets since 2001. At the liquid nitrogen temperature, these bulks have trapped over 1 T inside the motor after being applied the pulsed field magnetization method. Increasing the flux of the field poles is the most straightforward way of improving the output power of the motor. Cooling down the bulk HTS magnets below the liquid nitrogen temperature provides an effective alternative to increase the magnetic flux trapping. In 2007, we exchanged the cryogen from liquid nitrogen to condensed neon. The key technology of this challenge is a rotary joint, introducing a fluid cryogen into the rotating body in the motor from the static reservoir. We have successfully developed a compact rotary joint which is smaller and lighter than the existent one (1/10 volume, 1/3 length and 1/12 weight). The present joint was manufactured and evaluated with liquid nitrogen and condensed neon. We presume a total heat loss of this rotary joint of less than 10 watts. Successful cooling and rotating tests of the bulk-HTS motor with this novel rotary joint are conducted.

  17. Development of the cryo-rotary joint for a HTS synchronous motor with Gd-bulk HTS field-pole magnets

    Energy Technology Data Exchange (ETDEWEB)

    Miki, M; Felder, B; Tsuzuki, K; Izumi, M [Department of Marine Electronics and Mechanical Engineering, Tokyo University of Marine Science and Technology, 2-1-6, Etchu-jima, Koto-ku, Tokyo 135-8533 (Japan); Hayakawa, H, E-mail: d082025@kaiyodai.ac.j [Kitano Seiki Co. Ltd., 7-17-3, Chuo, Ohta-ku, Tokyo 143-0024 (Japan)

    2010-06-01

    We have studied a prototype of an axial-gap type synchronous motor with Gd-bulk HTS field-pole magnets since 2001. At the liquid nitrogen temperature, these bulks have trapped over 1 T inside the motor after being applied the pulsed field magnetization method. Increasing the flux of the field poles is the most straightforward way of improving the output power of the motor. Cooling down the bulk HTS magnets below the liquid nitrogen temperature provides an effective alternative to increase the magnetic flux trapping. In 2007, we exchanged the cryogen from liquid nitrogen to condensed neon. The key technology of this challenge is a rotary joint, introducing a fluid cryogen into the rotating body in the motor from the static reservoir. We have successfully developed a compact rotary joint which is smaller and lighter than the existent one (1/10 volume, 1/3 length and 1/12 weight). The present joint was manufactured and evaluated with liquid nitrogen and condensed neon. We presume a total heat loss of this rotary joint of less than 10 watts. Successful cooling and rotating tests of the bulk-HTS motor with this novel rotary joint are conducted.

  18. Thermodynamic and Mechanical Analysis of a Thermomagnetic Rotary Engine

    International Nuclear Information System (INIS)

    Fajar, D M; Khotimah, S N; Khairurrijal

    2016-01-01

    A heat engine in magnetic system had three thermodynamic coordinates: magnetic intensity ℋ, total magnetization ℳ, and temperature T, where the first two of them are respectively analogous to that of gaseous system: pressure P and volume V. Consequently, Carnot cycle that constitutes the principle of a heat engine in gaseous system is also valid on that in magnetic system. A thermomagnetic rotary engine is one model of it that was designed in the form of a ferromagnetic wheel that can rotates because of magnetization change at Curie temperature. The study is aimed to describe the thermodynamic and mechanical analysis of a thermomagnetic rotary engine and calculate the efficiencies. In thermodynamic view, the ideal processes are isothermal demagnetization, adiabatic demagnetization, isothermal magnetization, and adiabatic magnetization. The values of thermodynamic efficiency depend on temperature difference between hot and cold reservoir. In mechanical view, a rotational work is determined through calculation of moment of inertia and average angular speed. The value of mechanical efficiency is calculated from ratio between rotational work and heat received by system. The study also obtains exergetic efficiency that states the performance quality of the engine. (paper)

  19. Thermodynamic and Mechanical Analysis of a Thermomagnetic Rotary Engine

    Science.gov (United States)

    Fajar, D. M.; Khotimah, S. N.; Khairurrijal

    2016-08-01

    A heat engine in magnetic system had three thermodynamic coordinates: magnetic intensity ℋ, total magnetization ℳ, and temperature T, where the first two of them are respectively analogous to that of gaseous system: pressure P and volume V. Consequently, Carnot cycle that constitutes the principle of a heat engine in gaseous system is also valid on that in magnetic system. A thermomagnetic rotary engine is one model of it that was designed in the form of a ferromagnetic wheel that can rotates because of magnetization change at Curie temperature. The study is aimed to describe the thermodynamic and mechanical analysis of a thermomagnetic rotary engine and calculate the efficiencies. In thermodynamic view, the ideal processes are isothermal demagnetization, adiabatic demagnetization, isothermal magnetization, and adiabatic magnetization. The values of thermodynamic efficiency depend on temperature difference between hot and cold reservoir. In mechanical view, a rotational work is determined through calculation of moment of inertia and average angular speed. The value of mechanical efficiency is calculated from ratio between rotational work and heat received by system. The study also obtains exergetic efficiency that states the performance quality of the engine.

  20. Strain measurements in a rotary engine housing

    Science.gov (United States)

    Lee, C. M.; Bond, T. H.; Addy, H. E.; Chun, K. S.; Lu, C. Y.

    1989-01-01

    The development of structural design tools for Rotary Combustion Engines (RCE) using Finite Element Modeling (FEM) requires knowledge about the response of engine materials to various service conditions. This paper describes experimental work that studied housing deformation as a result of thermal, pressure and mechanical loads. The measurement of thermal loads, clamping pressure, and deformation was accomplished by use of high-temperature strain gauges, thermocouples, and a high speed data acquisition system. FEM models for heat transfer stress analysis of the rotor housing will be verified and refined based on these experimental results.

  1. Dynamic behaviour of rotary lip seal

    Directory of Open Access Journals (Sweden)

    El gadari M.

    2014-01-01

    Full Text Available We report on the dynamic behavior of a rotary lip seal by considering the interaction between lip, film and shaft roughness assumed to have a periodic form. The nonlinearities of stiffness and viscosity of the film are taken into account in a mass-spring-dumper model. Using the harmonic balance method, analytical prediction of the lip displacement is obtained, the frequency response is provided and the effect of the shaft undulation on the amplitude jumps of the lip displacement and on the film thickness fluctuations are discussed. The results have direct applications in reducing leakage that may occur between a smooth lip seal and a rough shaft.

  2. Numerical study on cavitation inception in the rotary valve of the hydraulic power steering system

    International Nuclear Information System (INIS)

    Ryu, Gwang Nyeon; Cho, Myung Hwan; Yoo, Jung Yul; Park, Sun Hong

    2009-01-01

    The rotary valve directs the power steering oil to either side of a power piston and relieves the driver of the effort to turn the wheel, when a driver begins to operate the vehicle. It is well known that the hiss noise occurring at that moment is caused mainly by cavitation of the oil inside the rotary valve. In this paper, two types of rotary valve (round and straight type) have been analyzed numerically using three-dimensional cavitation model embedded in the commercial code, FLUENT v6.2 and the results have been compared with the measured hiss noise level in a semi-anechoic chamber. The volume of the oil vapor generated from cavitation was larger in Round type valve which has a convex shape of the sleeve grooves than in Straight type valve which has a rectangular shape of the sleeve grooves. The hiss noise level of Round type valve was higher than that of Straight type valve as well. These results mean that the hiss noise can be reduced by the change of the shape of the grooves.

  3. Processing precious metals in a top-blown rotary converter

    Science.gov (United States)

    Whellock, John G.; Matousek, Jan W.

    1990-09-01

    Copper-nickel/platinum-palladium flotation concentrates produced by the Stillwater Mining Company were smelted and refined in an integrated pilot plant consisting of a submerged-arc electric furnace and top-blown rotary converter. The conversion of high-iron electric furnace mattes was achieved with apparent oxygen efficiencies in excess of 100 percent. Platinum and palladium recoveries averaged 99 percent, and copper and nickel recoveries were 94 percent.

  4. Safety analysis for push-mode and rotary-mode core sampling

    International Nuclear Information System (INIS)

    Milliken, N.J.; Geschke, G.R.

    1995-01-01

    This safety analysis analyzes using the push-mode core sampling truck in the push-mode and the rotary-mode core sampling trucks in both the push- and rotary-modes to retrieve core samples that, once taken and analyzed, will yield waste characterization data for the hazardous waste tanks at the Hanford Site. Operation of the core sampling trucks in both the push- and rotary-modes was reviewed to determine whether the release of radioactive materials could occur during operation. It was concluded that there are three credible scenarios: a sample spill outside of the tank, a steam release event, and an unfiltered release to the environment during continuous exhauster operation. The probability of a sample spill was found to be 10 -4 /event, the probability of a steam release event was determined to fall in the unlikely range (10 -2 /event to 10 -4 /event), and the probability of an unfiltered release was calculated to be 5 x 10 -3 /year. Typically, events with probabilities of 10 -6 /event or less are not considered to be risk significant, and the consequences usually are not analyzed. The three accident scenarios were analyzed to calculate the dose consequences. It was determined that the steam release event is the bounding accident. The onsite and offsite dose consequences for this event are calculated to be 0.24 Sv (24 rem) and 3.2 x 10 -4 Sv (32 mrem), respectively. These consequences are below the risk acceptance guidelines for an unlikely event, as established in WHC-CM-4-46, Nonreactor Facility Safety Analysis Manual. With the design features and the use of the controls presented in Section 8.0, this operation represents a minimal risk

  5. Method to Increase the Coupling Force in a Construction Machine

    Directory of Open Access Journals (Sweden)

    Tsipurskij Il’ja

    2017-01-01

    Full Text Available This paper discusses a possible method to increase the coupling tractive force track-wheel locomotion of construction machines. Sufficient tractive coupling force allows organizing translational displacement of the machine under above-medium load modes during operation of overburden chain excavators, tower cranes and gantry cranes in outdoors environments. A mechanism is examined to convert rotary motion into rectilinear motion using the example of a gear and rail, with kinematic calculations quoted. Analysis of the “force couple” system is proposed to identify free traction forces. Factors are established that influence the machine’s working movements. Equations to calculate tractive forces in track-wheel locomotion are described. A laboratory complex is presented where students of mechanical engineering gain practical skills in mastering the production process of soil excavation and the influence of the coupling tractive force during the machine’s operation. As practical recommendation, the paper describes a device made of a balancing lever, drive cogwheel and tractive chain to implement the required tractive force of the trolley in coupling; this solution’s efficiency is demonstrated for experimental works on hard soils with high coefficient of difficulty.

  6. Testing of a Rotary Micro-filter for Hanford Applications

    International Nuclear Information System (INIS)

    Poirier, M.R.; Herman, D.T.; Stefanko, D.B.; Fink, S.D.

    2009-01-01

    Savannah River National Laboratory (SRNL) researchers are investigating and developing a rotary micro-filter for solid-liquid separation applications with emphasis on deployment in radioactive services. The Department of Energy (DOE) Office of Waste Processing employed the SRNL team to evaluate the use of this rotary micro-filter for the Hanford Supplemental Pretreatment process. The authors tested a full-scale, 25-disk filter unit containing 0.5 μ filter media using a Hanford Tank AN-105 simulant at solids loadings of 0.06, 0.29, and 1.29 wt %. Based on recommendations from prior tests, the authors modified the filter unit by replacing the primary mechanical seal with an air seal. They also replaced the bushing with alternate materials of construction aimed at extended mean time between maintenance events. The testing provides the following conclusions. - The rotary filter produces a higher flux than the crossflow filter for the Hanford simulant. The gain in performance is less than previously seen for Savannah River Site simulants. - Filtrate clarity proved excellent with turbidity of <4 NTU (nephelometric turbidity units) in all samples. - Inspection of the primary mechanical seal faces after ∼140 hours of operation showed an expected minimal amount of initial wear, no passing of process fluid through the seal faces, and very little change in the air channeling grooves on the stationary face. - Some polishing of surfaces occurred at the bottom of the shaft bushing. The authors recommend improving the shaft bushing by holding it in place with a locking ring and incorporating grooves to provide additional cooling. - The authors recommend that Hanford test other pore size media to determine the optimum pore size for Hanford waste. - During final facility operation, the filter should be rinsed with filtrate or dilute caustic and drained prior to an extended shutdown to prevent the formation of a layer of settled solids on top of the filter disks. (authors)

  7. Forming of Hollow Shaft Forging From Titanium Alloy Ti6Al4V by Means of Rotary Compression

    Directory of Open Access Journals (Sweden)

    Tomczak J.

    2015-04-01

    Full Text Available This paper presents chosen results of theoretical-experimental works concerning forming of hollow shafts forgings from titanium alloys, which are applied in aviation industry. At the first stage of conducted analysis, the forging forming process was modeled by means of finite element method. Calculations were made using software Simufact Forming. On the basis of performed simulations optimal parameters of rotary compression process were determined. Next, experimental tests of forging forming in laboratory conditions were made. For the research needs, a forging aggregate, designed by the Authors, was used. Conducted research works confirmed the possibility of metal forming (by means of rotary compression of hollow shafts from hard workable titanium alloys. Numerous advantages of rotary compression process, make it attractive both for low series production (aircraft industry and for mass production (automotive industry.

  8. Fuel-air mixing and distribution in a direct-injection stratified-charge rotary engine

    Science.gov (United States)

    Abraham, J.; Bracco, F. V.

    1989-01-01

    A three-dimensional model for flows and combustion in reciprocating and rotary engines is applied to a direct-injection stratified-charge rotary engine to identify the main parameters that control its burning rate. It is concluded that the orientation of the six sprays of the main injector with respect to the air stream is important to enhance vaporization and the production of flammable mixture. In particular, no spray should be in the wake of any other spray. It was predicted that if such a condition is respected, the indicated efficiency would increase by some 6 percent at higher loads and 2 percent at lower loads. The computations led to the design of a new injector tip that has since yielded slightly better efficiency gains than predicted.

  9. Replacement of the rotary specimen rack in the U.S. Geological Survey TRIGA Reactor (GSTR)

    International Nuclear Information System (INIS)

    Rusling, D.H.; Helfer, P.G.; Perryman, R.E.; Smith, W.L.

    1986-01-01

    A new rotary specimen rack was installed in the GSTR on November 13, 1985. The new rack has been modified to allow the pneumatic unloading of samples. Instructions for the removal and installation of the rotary specimen rack were provided by GA Technologies. The first step was to prepare the core for removal of the control rods, T/C fuel elements, and the central thimble. The rack was weighted prior to removal to ensure that it could not float to the surface. The old rack was stored at the side of the tank. Radiation measurements were made with an underwater ion chamber. (author)

  10. TESTING OF THE SECOND GENERATION SPINTEK ROTARY FILTER -11357

    Energy Technology Data Exchange (ETDEWEB)

    Herman, D.; Poirier, M.; Fowley, M.; Keefer, M.; Huff, T.

    2011-02-02

    The SpinTek rotary microfilter has been developed under the Department of Energy (DOE) Office of Environmental Management (EM) for the purpose of deployment in radioactive service in the DOE complex. The unit that was fabricated and tested is the second generation of the filter that incorporates recommended improvements from previous testing. The completion of this test satisfied a key milestone for the EM technology development program and technology readiness for deployment by Savannah River Remediation in the Small Column Ion Exchange and Sludge Washing processes at the Savannah River Site (SRS). The Savannah River National Laboratory (SRNL) contracted SpinTek Filtration to fabricate a full scale 25 disk rotary filter and perform a 1000 hour endurance test with a simulated SRS sludge. Over 1500 hours of operation have been completed with the filter. SpinTek Filtration fabricated a prototypic 25 disk rotary filter including updates to manufacturing tolerances, an updated design to the rotary joint, improved cooling to the bottom journal, decreases in disk and filter shaft hydraulic resistances. The filter disks were fabricated with 0.5 {micro} pore size, sintered-metal filter media manufactured by Pall Corporation (M050). After fabrication was complete, the filter passed acceptance tests demonstrating rejection of solids and clean water flux with a 50% improvement over the previous filters. Once the acceptance test was complete, a 1000 hour endurance test was initiated simulating a sludge washing process. The test used a simulated SRS Sludge Batch 6 recipe. The insoluble solids started at 5 wt% and were raised to 10 and 15 wt% insoluble solids to simulate the concentration of a large volume tank. The filter system was automated and set up for 24 hour unattended operation. To facilitate this, process control logic was written to operate the filter. During the development it was demonstrated that the method of starting and stopping the filter can affect the build

  11. Case studies of heat conduction in rotary drums with L-shaped lifters via DEM

    Directory of Open Access Journals (Sweden)

    Qiang Xie

    2018-03-01

    Full Text Available Rotary drums are widely used in numerous processes in industry to handle granular materials. In present work, heat transfer processes in drums with L-shaped lifters have been investigated by coupling the discrete element method (DEM with heat transfer model. Effects of both operational and structural parameters have been analyzed. It is found that increasing rotational speed could improve heat transfer to a certain extent, however, just in relatively low speed stage. When lifter number increases, the heat transfer speed slightly decreases. An increasing lifter height could promote heat transfer first and then reduces it, but the amplitude of variation keeps small. The heat transfer rate descends with increasing lifter width. The heat transfer mechanisms have also been discussed by comparing mixing rates, total contact areas for thermal conduction, time constants (TC indicating apparent heat transfer rate and effective heat transfer coefficients(HTC. It is concluded that dynamic conduction due to particle flow is dominated in all cases. The L-shaped lifers are turned out not a good choice when heat conduction between particles is prominent.

  12. Microstructures and mechanical properties of pure Mg processed by rotary swaging

    International Nuclear Information System (INIS)

    Gan, W.M.; Huang, Y.D.; Wang, R.; Wang, G.F.; Srinivasan, A.; Brokmeier, H.-G.; Schell, N.; Kainer, K.U.; Hort, N.

    2014-01-01

    Highlights: • Grain size of pure Mg can be effectively reduced by rotary swaging processing. • The dominated texture of the swaged pure Mg was a basal fibre. • Twinning and non-basal plane sliding accommodated the swaging process. • Gradient texture distribution was observed through the rod diameter. • There existed a slight shear deformation on the surface of the swaged rod. - Abstract: Microstructures and tensile properties of commercial pure magnesium processed by rotary swaging (RS) technique were investigated. Bulk and gradient textures in the RS processed Mg were characterised by neutron and synchrotron diffractions, respectively. Grains of the pure Mg were gradually refined with increase in the RS passes, which largely contributed to an increase in the tensile yield strength. A dominated basal fibre texture was observed in the RS processed pure Mg. Accommodated twinning deformation was also observed. Both the optical observations and texture analyses through the diameter of the swaged rod showed a gradient evolution in microstructure

  13. Research and design of module supporting and rotary device in hot cell

    International Nuclear Information System (INIS)

    Wu Wenguang; Song Changfei; Chen Mingchi

    2013-01-01

    Background: This paper introduced a device for tandem accelerator project, designed for the radioactive target source module maintaining and testing. Purpose: The module is required to be lifting, rotary and precise orientation in technology. Methods: We designed the structure of rotary drum, supporting drum and screw lifting device to achieve the function. In circumference, we adopt the project with electro-motion cursory locate, hand-motion precise locate, sensor location detect and cylinder locate pin, the measure is safe and trustiness. Results: Via experimentation, all technology targets are fulfilled, and the rationality and reliability of the device has been validated. Conclusions: The successful development of this device provides a good direction and reference for radioactive areas such as accelerator, hot cell, reactor etc., and can be adapted to its capability of long-distance shield operating, maintaining or testing. (authors)

  14. Rotary Valve FY 2016 Highlights

    Energy Technology Data Exchange (ETDEWEB)

    Fitsos, P. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2016-12-07

    The fiscal year started with the Rotary Valve (RV) being reassembled after having crashed in June of 2015. The crash occurred when the RV inner surface contacted the housing. The cause of the crash was never confirmed. No particles were found in the 2.5 thousandths of an inch gap and the filters the helium gas passed through were all clean. There were marks on the bearings that looked like electrostatic discharge as shown below in Figure 1. These marks hadn’t been seen before and there were similar discharge marks on some of the ball bearings. Examples of this were found in a literature search of bearing failures. This leads to a possible cause due to this arcing affecting the rotational accuracy of the bearings driving the RV into the housing.

  15. Development of a three-dimensional CFD model for rotary lime kilns

    Energy Technology Data Exchange (ETDEWEB)

    Lixin Tao; Blom, Roger (FS Dynamics Sweden AB, Goeteborg (Sweden)); Nordgren, Daniel (Innventia, Stockholm (Sweden))

    2010-11-15

    In the calcium loop of the recovery cycle in a Kraft process of pulp and paper production, rotary lime kilns are used to convert the lime mud, mainly CaCO3, back to quick lime, CaO, for re-use in the causticizing process. The lime kilns are one of the major energy consumption devices for paper and pulp industry. Because of the rising oil price and new emission limits, the pulp mills have been forced to look for alternative fuels for their lime kilns. One interesting alternative to oil, often easily available at pulp mills, is biofuels such as sawdust and bark. However the practical kiln operation often encounters some difficulties because of the uncertainties around the biofuel impact on the lime kiln performance. A deeper understanding of the flame characteristics is required when shifting from oil to biofuels. Fortunately recent advances in modern Computational Fluid Dynamics, CFD, have provided the possibility to study and predict the detailed flame characteristics regarding the lime kiln performance. In this project a three-dimensional CFD model for rotary lime kilns has been developed. To simulate a rotary lime kiln the developed CFD model integrates the three essential sub-models, i.e. the freeboard hot flow model, the lime bed model and the rotating refractory wall model and it is developed based on the modern CFD package: FLUENT which is commercially available on the market. The numerical simulations using the developed CFD model have been performed for three selected kiln operations fired with three different fuel mixtures. The predicted results from the CFD modelling are presented and discussed in order to compare the impacts on the kiln performance due to the different firing conditions. During the development, the lime kiln at the Soedra Cell Moensteraas mill has been used as reference kiln. To validate the CFD model, in-plant measurements were carried out in the Moensteraas lime kiln during an experiment campaign. The results obtained from the

  16. Experimental and numerical investigation of the fluid flow in a side-ported rotary engine

    International Nuclear Information System (INIS)

    Fan, Baowei; Pan, Jianfeng; Tang, Aikun; Pan, Zhenhua; Zhu, Yuejin; Xue, Hong

    2015-01-01

    Highlights: • An optical side-ported rotary engine test bed has been set up and tested by PIV. • A three-dimensional dynamic simulation model is established. • Experiment and numerical simulation are combined to study the flow mechanisms. • A counterclockwise flow pattern was found in the combustion chamber in the experiment. • The effect of various parameters on the flow field is studied by numerical simulation. - Abstract: The side-ported rotary engine is a potential alternative to the reciprocating engine because of its favorable performance at low speed. The performance of side-ported rotary engines is strongly influenced by the flow field in the combustion chamber. In this study, an optical side-ported rotary engine test-bed was built and PIV was employed to measure the flow field in the rotor housing central plane. From experiment results, a counterclockwise swirl was detected in the rotor housing central plane. Meanwhile, a three-dimensional dynamic mesh and turbulent flow model was integrated and simulated using the Fluent CFD software. The three-dimensional dynamic simulation model was validated by comparison with experimental results. In addition, the effect of three major parameters on the flow field in the combustion chamber, namely rotating speed, intake pressure and intake angle were numerically investigated. The results show that a swirl forms in the middle and front of the combustion chamber during the intake stroke under low rotating speed. This is in line with the swirl detected in the rotor housing central plane though the PIV experiment at 600 rpm. Furthermore, the flow field, volume coefficient and average turbulence kinetic energy in the combustion chamber were studied in detail by varying rotating speed, intake pressure and intake angle

  17. An electro-thermally activated rotary micro-positioner for slider-level dual-stage positioning in hard disk drives

    International Nuclear Information System (INIS)

    Lau, Gih Keong; Chong, Nyok Boon; Yang, Jiaping; Tan, Cheng Peng

    2016-01-01

    Slider-level micro-positioners are useful to assist a voice coil motor to perform fine head positioning over a Tb/in 2 magnetic disk. Recently, a new kind of slider-level micro-positioner was developed using the thermal unimorph of the Si/SU8 composite. It has the advantages of a very small footprint and high mechanical resonant frequency, but its stroke generation is inadequate, with a 50 nm dynamic stroke at 1 kHz. There is a need for a larger thermally induced stroke. This paper presents a rotary design of an electrothermal micro-positioner to address the stroke requirements without consuming more power or decreasing the mechanical resonant frequency. Experimental studies show the present rotary design can produce a six-fold larger displacement, as compared to the previous lateral design, while possessing a 35 kHz resonant frequency. In addition, simple analytical models were developed to estimate: (i) the rotational stiffness and system’s natural frequency, (ii) thermal unimorph bending and stage rotation, and (iii) the system’s thermal time constant for this rotary electro-thermal micro-positioner. This study found that this rotary electro-thermal micro-positioner can meet the basic stroke requirement and high mechanical resonant frequency for a moving slider, but its thermal cut-off frequency needs to be increased further. (paper)

  18. Root Canal Cleaning Efficacy of Rotary and Hand Files Instrumentation in Primary Molars

    Science.gov (United States)

    Nazari Moghaddam, Kiumars; Mehran, Majid; Farajian Zadeh, Hamideh

    2009-01-01

    INTRODUCTION: Pulpectomy of primary teeth is commonly carried out with hand files and broaches; a tricky and time consuming procedure. The purpose of this in vitro study was to compare the cleaning efficacy and time taken for instrumentation of deciduous molars using hand K-files and Flex Master rotary system. MATERIALS AND METHODS: In this study, 68 canals of 23 extracted primary molars with at least two third intact roots and 7-12 mm length were selected. After preparing an access cavity, K-file size #15 was introduced into the root canal and India ink was injected with an insulin syringe. Sixty samples were randomly divided in to experimental groups in group I (n=30), root canals were prepared with hand K-files; in group II (n=30), rotary Flex Master files were used for instrumentation, and in group III 8 remained samples were considered as negative controls. After clearing and root sectioning, the removal of India ink from cervical, middle, and apical thirds was scored. Data was analyzed using student's T-test and Mann-Whitney U test. RESULTS: There was no significant difference between experimental groups cleaning efficacy at the cervical, middle and apical root canal thirds. Only the coronal third scored higher in the hand instrumented group (PInstrumentation with Flex Master rotary files was significantly less time consuming (Protary technique. PMID:23940486

  19. Effectiveness of Rotary Endodontic Instruments on Smear Layer Removal in Root Canals of Primary Teeth: A Scanning Electron Microscopy Study.

    Science.gov (United States)

    Subramaniam, Priya; Girish Babu, K L; Tabrez, T A

    2016-01-01

    The present SEM study was undertaken to evaluate the effect of root canal instrumentation using both manual and rotary files in the root canals of primary anterior teeth. Thirty freshly extracted primary maxillary incisors were divided into 3 groups of 10 teeth each. In Group I, root canals were instrumented with rotary NiTi files; in Group II, the root canals were instrumented using manual NiTi K files and; in Group III, manual instrumentation was done with stainless steel K files. Longitudinal sections were prepared and processed for observation under SEM at the coronal, middle and apical thirds. Scoring of smear layer was done according to Hulsmann and the data obtained was subjected to statistical analysis. Rotary files cleaned the coronal and middle thirds of root canals more effectively. Statistically there was no significant difference between the groups. Lowest score of 2.6 in the apical third of root canals was seen with hand NiTi files. Rotary instrumentation was as effective as manual instrumentation in removal of smear layer in the root canals of primary anterior teeth.

  20. Comparison of the cleaning capacity of Mtwo and Pro Taper rotary systems and manual instruments in primary teeth

    Science.gov (United States)

    Azar, Mohammad Reza; Safi, Laya; Nikaein, Afshin

    2012-01-01

    Background: Root canal cleaning is an important step in endodontic therapy. In order to develop better techniques, a new generation of endodontic instruments has been designed. The aim of this study was to compare the effectiveness of manual K-files (Mani Co, Tokyo, Japan) and two rotary systems–Mtwo (Dentsply-Maillefer, Ballaigues, Switzerland) and ProTaper (VDW, Munich, Germany)–for root canal preparation in primary molars. Materials and Methods: India ink was injected to 160 mesiobuccal and distal root canals of mandibular primary molars. The teeth were randomly divided into three experimental groups and one control group. In each experimental group, either manual instruments (K-files) or rotary instruments (Mtwo or ProTaper) were used to prepare root canals. After cleaning the canals and clearing the teeth, ink removal was evaluated with a stereomicroscope. Statistical analysis was done with Kruskal–Wallis and Friedman tests. Results: There were no significant differences in cleaning efficiency between manual and rotary instruments. Only ProTaper files performed significantly better in the coronal and middle thirds than in the apical third of the root canal. Conclusion: Manual K-files and the Mtwo and ProTaper rotary systems showed equally acceptable cleaning ability in primary molar root canals. PMID:22623929

  1. Comparison of the cleaning capacity of Mtwo and ProTaper rotary systems and manual instruments in primary teeth

    Directory of Open Access Journals (Sweden)

    Mohammad Reza Azar

    2012-01-01

    Full Text Available Background: Root canal cleaning is an important step in endodontic therapy. In order to develop better techniques, a new generation of endodontic instruments has been designed. The aim of this study was to compare the effectiveness of manual K-files (Mani Co, Tokyo, Japan and two rotary systems-Mtwo (Dentsply-Maillefer, Ballaigues, Switzerland and ProTaper (VDW, Munich, Germany-for root canal preparation in primary molars. Materials and Methods: India ink was injected to 160 mesiobuccal and distal root canals of mandibular primary molars. The teeth were randomly divided into three experimental groups and one control group. In each experimental group, either manual instruments (K-files or rotary instruments (Mtwo or ProTaper were used to prepare root canals. After cleaning the canals and clearing the teeth, ink removal was evaluated with a stereomicroscope. Statistical analysis was done with Kruskal-Wallis and Friedman tests. Results: There were no significant differences in cleaning efficiency between manual and rotary instruments. Only ProTaper files performed significantly better in the coronal and middle thirds than in the apical third of the root canal. Conclusion: Manual K-files and the Mtwo and ProTaper rotary systems showed equally acceptable cleaning ability in primary molar root canals.

  2. Scanning electron microscopic evaluation of the influence of manual and mechanical glide path on the surface of nickel-titanium rotary instruments in moderately curved root canals: An in-vivo study

    Science.gov (United States)

    Patel, Dishant; Bashetty, Kusum; Srirekha, A.; Archana, S.; Savitha, B.; Vijay, R.

    2016-01-01

    Aim: The aim of this study was to evaluate the influence of manual versus mechanical glide path (GP) on the surface changes of two different nickel-titanium rotary instruments used during root canal therapy in a moderately curved root canal. Materials and Methods: Sixty systemically healthy controls were selected for the study. Controls were divided randomly into four groups: Group 1: Manual GP followed by RaCe rotary instruments, Group 2: Manual GP followed by HyFlex rotary instruments, Group 3: Mechanical GP followed by RaCe rotary instruments, Group 4: Mechanical GP followed by HyFlex rotary instruments. After access opening, GP was prepared and rotary instruments were used according to manufacturer's instructions. All instruments were evaluated for defects under standard error mean before their use and after a single use. The scorings for the files were given at apical and middle third. Statistical Analysis Used: Chi-squared test was used. Results: The results showed that there is no statistical difference between any of the groups. Irrespective of the GP and rotary files used, more defects were present in the apical third when compared to middle third of the rotary instrument. Conclusion: Within the limitations of this study, it can be concluded that there was no effect of manual or mechanical GP on surface defects of subsequent rotary file system used. PMID:27994317

  3. Comparison of Single Visit Post Endodontic Pain Using Mtwo Rotary and Hand K-File Instruments: A Randomized Clinical Trial

    Directory of Open Access Journals (Sweden)

    Mohamad Kashefinejad

    2016-08-01

    Full Text Available Objectives: Pain is an unpleasant outcome of endodontic treatment that can be unbearable to patients. Instrumentation techniques may affect the frequency and intensity of post-endodontic pain. This study aimed to compare single visit post endodontic pain using Mtwo (NiTi rotary and hand K-file instruments.Materials and Methods: In this randomized controlled trial, 60 teeth with symptomatic irreversible pulpitis in 53 patients were selected and randomly assigned into two groups of 30 teeth. In group A, the root canals were prepared with Mtwo (NiTi rotary instruments. In group B, the root canals were prepared with hand K-file instruments. Pain assessment was implemented using visual analog scale (VAS at four, eight, 12 and 24 hours after treatment. The acquired data were analyzed using chi-square, Mann-Whitney U and Student’s t-test (P<0.05.Results: Patients treated with rotary instruments experienced significantly less post-endodontic pain than those treated with hand instruments (P<0.001.Conclusion: The use of Mtwo (NiTi rotary instruments in root canal preparation contributed to lower incidence of postoperative pain than hand K-files.

  4. Modeling the Mixing of Components in a Rotary Kiln While Burning Municipal Waste to Ensure Rational Use of Energy

    Directory of Open Access Journals (Sweden)

    Krot O.P.

    2017-08-01

    Full Text Available In Ukraine municipal waste is collected and delivered to a landfill. Municipal waste can be used as fuel to generate additional heat and electricity. The primary advantages of incineration are that waste volumes are reduced by an estimated, and the need for land and landfill space is greatly reduced. The plant has been designed by North–East Scientific Center using a thermocatalytic waste gas purification system with highly efficient dioxins reduction and heat energy recovery system. The technology of waste neutralization includes: a rotary kiln, an afterburner chamber, a new catalytic technologies for the treatment, a heat exchanger for heating combustion air, supply of alkali solution into the gas-escape channel, a carbon fiber adsorption filter. The organization of the right process of waste mixing in the rotary kiln allows increasing the efficiency of combustion, to equalize the combustion temperatures of the components of the waste and the completeness of the burning out of hazardous substances, which reduces the risk of their getting into the ash. The goal of the research is to build an analytical mathematical model of mixing of components in a rotary kiln. The model is based on the mathematical apparatus of Markov chains. The model allows to determine the concentration of the key component in any elementary volume of material circulating in the rotary kiln at any time and to calculate the statistical characteristics of the homogeneity of the mixture. The model will be used to research new designs of the equipment with rotary kilns.

  5. Modeling emulsification processes in rotary-disk mixers

    Science.gov (United States)

    Laponov, S. V.; Shulaev, N. S.; Ivanov, S. P.; Bondar', K. E.; Suleimanov, D. F.

    2017-10-01

    This article presents the experimental studies results of emulsification processes in liquid-liquid systems in rotary-disk mixers, allowing regulating the distribution of dispersed particles by changing the process conditions and the ratio of the dispersed phase. It is shown that with the increase of mixer’s revolutions per minute (RPM), both the size of dispersed particles and the deviation of dispersed particles sizes from the average decrease. The increase of the dispersed particles part results in the increase of particles average sizes at the current energy consumption. Discovered relationships can be used in the design of industrial equipment and laboratory research.

  6. Steady flow torques in a servo motor operated rotary directional control valve

    International Nuclear Information System (INIS)

    Wang, He; Gong, Guofang; Zhou, Hongbin; Wang, Wei

    2016-01-01

    Highlights: • A novel servo motor operated rotary directional control valve is proposed. • Steady flow torque is a crucial issue that affects rotary valve performance. • Steady flow torque is analyzed on the aspects of theory, simulation and experiment. • Change law of the steady flow torque with spool rotation angle is explored. • Effect of pressure drop and flow rate on the steady flow torque is studied. - Abstract: In this paper, a servo motor operated rotary directional control valve is proposed, and a systematic analysis of steady flow torques in this valve is provided by theoretical calculation, CFD simulation and experimental test. In the analysis, spool rotation angle corresponding to the maximum orifice opening is tagged as 0°. Over a complete change cycle of the orifice, the range of spool rotation angle is symmetric about 0°. The results show that the direction of steady flow torques in this valve is always the direction of orifice closing. The steady flow torques serve as resistances to the spool rotation when the orifice opening increases, while impetuses to the spool rotation when the orifice opening decreases. At a certain pressure drop or flow rate, steady flow torques are approximately equal and opposite when at spool rotation angles which are symmetric about 0°. When the spool rotates from 0°, at a certain pressure drop, their values increase first then decrease with the spool rotation and reach their maximum values at an angle corresponding to about 1/2 of the maximum orifice opening, and at a certain flow rate, their values increase with the spool rotation. The steady flow torques in this valve are the sums of those in the meter-in and meter-out valve chambers. At a certain spool rotation angle, steady flow torques in the meter-in and meter-out valve chambers are approximately proportional to the pressure drop and the second power of the flow rate through the orifice. Theoretical calculation and CFD simulation can be validated by

  7. Development, characterization and testing of tungsten doped DLC coatings for dry rotary swaging

    Directory of Open Access Journals (Sweden)

    Hasselbruch Henning

    2015-01-01

    Full Text Available The extensive use of lubricant during rotary swaging is particularly required for a good surface finish of the work piece and the reduction of tool wear. Abandonment of lubricant would improve the ecological process-balance and could also accelerate for further work piece refinements. Also cleaning of the manufactured components becomes obsolete. Thus, a dry machining is highly innovative, consequently new strategies to substitute the lubricant functions become necessary. To encounter the changed tribological conditions due to dry rotary swaging, low friction, tungsten doped, hard DLC coatings and structured surfaces are the most promising approaches. In this work the development of hard coating by means of reactive magnetron sputtering is presented, a promising layer variant is deposited on a set of tools and then tested and investigated in real use.

  8. Experimental analysis of IMEP in a rotary combustion engine. [Indicated Mean Effective Pressure

    Science.gov (United States)

    Schock, H. J.; Rice, W. J.; Meng, P. R.

    1981-01-01

    This experimental work demonstrates the use of a NASA designed, real time Indicated Mean Effective Pressure (IMEP) measurement system which will be used to judge proposed improvements in cycle efficiency of a rotary combustion engine. This is the first self-contained instrument that is capable of making real time measurements of IMEP in a rotary engine. Previous methods used require data recording and later processing using a digital computer. The unique features of this instrumentation include its ability to measure IMEP on a cycle by cycle, real time basis and the elimination of the need to differentiate the volume function in real time. Measurements at two engine speeds (2000 and 3000 RPM) and a full range of loads are presented, although the instrument was designed to operate to speeds of 9000 RPM.

  9. Performance of A Horizontal Cylinder Type Rotary Dryer for Drying Process ofOrganic Compost from Solid Waste Cocoa Pod

    Directory of Open Access Journals (Sweden)

    Sukrisno Widyotomo

    2008-07-01

    Full Text Available Cocoa pod husk is the bigest component of cocoa pod, about 70% of total ht of mature pod, and to potentially used as organic compost source. Poten tial solid waste of cocoa pod husk from a cocoa processing centre is about 15— 22 m3/ha/year. A cocoa plantation needs about 20—30 ton/ha/year of organic matters. One of important steps in compos processing technology of cocoa pod solid waste is drying process. Organic compost with 20% moisture content is more easy in handling, application, storage and distribution. Indonesian Coffee and Cocoa Research Institute has designed and tested a horizontal cylinder type rotary dryer for drying process of organic compos from solid waste cocoa pod with kerosene burner as energy sources. The objective of this research is to study performance of a horizontal cylinder type rotary dryer using kerosene burner as energy source for drying process of organic compost from solid waste cocoa pod. The material used was solid waste cocoa pod with 70—75% moisture content (wet basis, 70% size particle larger than 4.76 mm, and 30% size particle less than 4.76 mm, 690—695 kg/m3 bulk density. Drying process temperatures treatment were 60OC, 80OC, and 100OC, and cylinder rotary speed treatments were 7 rpm, 10 rpm, dan 16 rpm. The results showed that dryer had capacity about 102—150 kg/h depend on drying temperature and cylinder rotary speed. Optimum operation condition at 100OC drying temperature, and 10 rpm cylinder rotary speed with drying time to reach final moisture content of 20% was 1,6 h, capacity 136,14 kg/ h, bulk density 410 kg/m3, porocity 45,15%, kerosene consumption as energy source was 2,57 l/h, and drying efficiency 68,34%. Key words : cocoa, drying, rotary dryer, compost, waste

  10. The Auto-Gopher: A Wireline Rotary-Percussive Deep Sampler

    Science.gov (United States)

    Bar-Cohen, Yoseph; Zacny, Kris; Badescu, Mircea; Lee, Hyeong Jae; Sherrit, Stewart; Bao, Xiaoqi; Paulsen, Gale L.; Beegle, Luther

    2016-01-01

    Accessing regions on planetary bodies that potentially preserved biosignatures or are presently habitable is vital to meeting NASA solar system "Search for Life" exploration objectives. To address these objectives, a wireline deep rotary-percussive corer called Auto-Gopher was developed. The percussive action provides effective material fracturing and the rotation provides effective cuttings removal. To increase the drill's penetration rate, the percussive and rotary motions are operated simultaneously. Initially, the corer was designed as a percussive mechanism for sampling ice and was demonstrated in 2005 in Antarctica reaching about 2 m deep. The lessons learned suggested the need to use a combination of rotation and hammering to maximize the penetration rate. This lesson was implemented into the Auto-Gopher-I deep drill which was demonstrated to reach 3-meter deep in gypsum. The average drilling power that was used has been in the range of 100-150 Watt, while the penetration rate was approximately 2.4 m/hr. Recently, a task has started with the goal to develop Auto-Gopher-II that is equipped to execute all the necessary functions in a single drilling unit. These functions also include core breaking, retention and ejection in addition drilling. In this manuscript, the Auto-Gopher-II, its predecessors and their capability are described and discussed.

  11. Optimal Power Flow Control by Rotary Power Flow Controller

    Directory of Open Access Journals (Sweden)

    KAZEMI, A.

    2011-05-01

    Full Text Available This paper presents a new power flow model for rotary power flow controller (RPFC. RPFC injects a series voltage into the transmission line and provides series compensation and phase shifting simultaneously. Therefore, it is able to control the transmission line impedance and the active power flow through it. An RPFC is composed mainly of two rotary phase shifting transformers (RPST and two conventional (series and shunt transformers. Structurally, an RPST consists of two windings (stator and rotor windings. The rotor windings of the two RPSTs are connected in parallel and their stator windings are in series. The injected voltage is proportional to the vector sum of the stator voltages and so its amplitude and angle are affected by the rotor position of the two RPSTs. This paper, describes the steady state operation and single-phase equivalent circuit of the RPFC. Also in this paper, a new power flow model, based on power injection model of flexible ac transmission system (FACTS controllers, suitable for the power flow analysis is introduced. Proposed model is used to solve optimal power flow (OPF problem in IEEE standard test systems incorporating RPFC and the optimal settings and location of the RPFC is determined.

  12. Perawatan Satu\tKunjungan\tpada\tPremolar Pertama Atas Menggunakan Protaper Rotary dan Restorasi Resin Komposit

    Directory of Open Access Journals (Sweden)

    Sherli Diana

    2013-06-01

    Full Text Available Preparasi kemomekanik pada saluran akar meliputi instrumentasi mekanis dan irigasi antibakteri yang secara prinsip dapat langsung mengeliminasi mikroorganisme pada sistem saluran akar. sejak diperkenalkan pada tahun 1988, instrumen rotary nikel-titanium (niti telah digunakan secara umum dalam perawatan endodontik karena kemampuannya membentuk saluran akar dengan prosedur komplikasi yang minimal. Tujuan dari laporan kasus ini adalah untuk memaparkan perawatan saluran akar satu kunjungan menggunakan protaper rotary dan restorasi resin komposit gigi premolar. Penderita pria 21 tahun datang ke RSGM Prof. Soedomo UGM Yogyakarta mengeluhkan gigi belakang atas kiri yang berlubang tapi tidak sakit dan pasien ingin  dirawat.Gigi  Premolar satu atas  kiri terdapat kavitas disto oklusal dengan pulpa terbuka. Pemeriksan objektif pada gigi 24 sondasi, perkusi, palpasi, dan tes termal menunjukkan hasil negatif.Pemeriksaan radiografis tidak terdapat lesi, lamina dura tidak terputus dan saluran akar jelas dan lurus. Pada kasus ini dilakukan perawatan saluran akar dengan menggunakan ProTaper rotary ( X-Smart, Dentsply. Pasca perawatan saluran akar, gigi premolar satu atas kiri dilakukan tumpatan resin komposit kelas II.Hasil evaluasi klinik saat kontrol tidak ada keluhan rasa sakit, pemeriksaan objektif juga tidak ada rasa sakit, warna gigi serasi dengan warna gigi tetangga.prognosis pada kasus ini baik dan tidak ada keluhan. Kesimpulan paska perawatan saluran akar satu kunjungan dengan instrumenrotary, tidak terdapat keluhan.Penggunaan Instrumen rotary Nikel-Titanium (NiTi sangat flexible dengan prosedur komplikasi yang minimal, dan hemat waktu. One Visit Treatment of Upper Premolar Tooth Using Rotary Protaper and Composite Resin Restoration. Chemomechanical preparation for root canal including mechanic instrumentation and anti-bacterial irrigation principally could eliminate microorganisms in root canal system. Many instruments and techniques have been

  13. A Four-Feet Walking-Type Rotary Piezoelectric Actuator with Minute Step Motion.

    Science.gov (United States)

    Liu, Yingxiang; Wang, Yun; Liu, Junkao; Xu, Dongmei; Li, Kai; Shan, Xiaobiao; Deng, Jie

    2018-05-08

    A four-feet walking-type rotary piezoelectric actuator with minute step motion was proposed. The proposed actuator used the rectangular motions of four driving feet to push the rotor step-by-step; this operating principle was different with the previous non-resonant actuators using direct-driving, inertial-driving, and inchworm-type mechanisms. The mechanism of the proposed actuator was discussed in detail. Transient analyses were accomplished by ANSYS software to simulate the motion trajectory of the driving foot and to find the response characteristics. A prototype was manufactured to verify the mechanism and to test the mechanical characteristics. A minimum resolution of 0.095 μrad and a maximum torque of 49 N·mm were achieved by the prototype, and the output speed was varied by changing the driving voltage and working frequency. This work provides a new mechanism for the design of a rotary piezoelectric actuator with minute step motion.

  14. Comparison of apical debris extrusion using a conventional and two rotary techniques.

    Science.gov (United States)

    Adl, Alireza; Sahebi, Safoora; Moazami, Fariborz; Niknam, Mahnaz

    2009-01-01

    Preparation techniques and instruments produce and push debris out of canals. This can induce inflammation within the periapical area. Therefore, instrumentation that causes less extrusion of debris is more desirable. The purpose of this in vitro study was to evaluate the quantity of debris extruded from the apical foramen during root canal preparation by using one hand, and two rotary instrumentation techniques. Three different groups each with 12 mesiobuccal roots of human maxillary first molar were instrumented using either step-back technique with hand instruments, FlexMaster or Mtwo rotary system. Debris extruded from the apical foramen during canal preparation was collected. The mean dry weights of debris were compared using one-way ANOVA. Step-back group had a significantly greater mean weight of debris compared to the other two groups (Pengine driven techniques were associated with less apical debris extrusion. [Iranian Endodontic Journal 2009;4(4):135-8].

  15. Thermal co-treatment of combustible hazardous waste and waste incineration fly ash in a rotary kiln.

    Science.gov (United States)

    Huber, Florian; Blasenbauer, Dominik; Mallow, Ole; Lederer, Jakob; Winter, Franz; Fellner, Johann

    2016-12-01

    As current disposal practices for municipal solid waste incineration (MSWI) fly ash are either associated with significant costs or negative environmental impacts, an alternative treatment was investigated in a field scale experiment. Thereto, two rotary kilns were fed with hazardous waste, and moistened MSWI fly ash (water content of 23%) was added to the fuel of one kiln with a ratio of 169kg/Mg hazardous waste for 54h and 300kg/Mg hazardous waste for 48h while the other kiln was used as a reference. It was shown that the vast majority (>90%) of the inserted MSWI fly ash was transferred to the bottom ash of the rotary kiln. This bottom ash complied with the legal limits for non-hazardous waste landfills, thereby demonstrating the potential of the investigated method to transfer hazardous waste (MSWI fly ash) into non-hazardous waste (bottom ash). The results of a simple mixing test (MSWI fly ash and rotary kiln bottom ash have been mixed accordingly without thermal treatment) revealed that the observed transformation of hazardous MSWI fly ash into non-hazardous bottom ash during thermal co-treatment cannot be referred to dilution, as the mixture did not comply with legal limits for non-hazardous waste landfills. For the newly generated fly ash of the kiln, an increase in the concentration of Cd, K and Pb by 54%, 57% and 22%, respectively, was observed. In general, the operation of the rotary kiln was not impaired by the MSWI fly ash addition. Copyright © 2016 Elsevier Ltd. All rights reserved.

  16. Material and energy flows in rotary kiln-electric furnace smelting of ferronickel alloy with energy saving

    International Nuclear Information System (INIS)

    Liu, Peng; Li, Baokuan; Cheung, Sherman C.P.; Wu, Wenyuan

    2016-01-01

    Highlights: • Establish the synergy relationship of material and energy in key RKEF processes. • Develop an analysis model to study energy saving with internal cycling of energy. • Analyze material and energy flow parameters and assess its associated synergy effect. • A methodology to evaluate the synergy and design indices of RKEF processes. - Abstract: An energy saving strategy with two energy saving measures has been proposed for reducing energy loss in the rotary kiln-electric furnace (RKEF) for the smelting of ferronickel alloy. One of the measures is to recover the waste heat of exhaust gas from the rotary kiln for preheating and dehydrating the wet laterite ores in the rotary dryer. Another measure is to recycle the furnace gas from the electric furnace into the rotary kiln as fuel. Based on the mass conservation and energy conservation laws, an analysis model of material and energy flows has been developed to understand the potential energy saving with the internal cycling of material and energy in the RKEF process. The analysis model not only considers the energy efficiency but also assess the synergy degree of system. Furthermore, the model also predicts the ratio of raw materials and the energy flow distribution to investigate residual heat and energy and analyze the effects of nickel content on energy flow. Finally, the evaluation methodology of synergy and the technic indices are also presented. Through the investigation of the synergy effect, the performance of the RKEF process can be evaluated and quantified for performance optimization in future.

  17. Influence of axial movement on fatigue of PROFILE* NI-TI rotary instruments: an in vitro evaluation

    Science.gov (United States)

    Avoaka, Marie-Chantal; Haïkel, Youssef

    2010-01-01

    The aim of this study was to evaluate the influence of the axial movement and the angle of curve (in degrees) on fatigue of nickel-titanium (Ni-Ti) ProFile’ rotary endodontic instruments. Ni-Ti ProFile’ rotary instruments (Maillefer SA, Ballaigues, Switzerland), 25 mm long in the range of ISO size 15 to 40 with two tapers (0.4 and 0.6) were evaluated. They are divided in two groups: the instruments with axial movement and those without axial movement. The system used to test the fatigue is maintained in mechanical conditions as close as possible to the clinical situation. The axial movement is in the order of 2mm in corono-apical direction with a frequency of 1Hz. The concave radii incorporating a notched V-form for guiding the instruments were: 5; 7,5 and 10 mm. The rotary system is mounted on an electric handpiece and rotated at 350 rpm speed as recommended by the manufacturers. The instruments are rotated until their separation, and the time, in seconds, is recorded. Statístícal evaluation is undertaken using a two-way t-test to identify significant differences between variables in the study (p engine drive ProFile’ instruments incorporating an axial movement and the instruments without axial movement with the same radius of curvature, size and taper. The incorporation of the axial movement increases significantly the life-span of the ProFile’ rotary instruments. This should reduce the risk of the instrument separation during the endodontic treatment. PMID:20507289

  18. Experimental Study of Drag Resistance using a Laboratory Scale Rotary Set-Up

    DEFF Research Database (Denmark)

    Erik Weinell, Claus; Olsen, Kenneth N.; Christoffersen, Martin W.

    2003-01-01

    This work covers an experimental study of the drag resistance of different painted surfaces and simulated large-scale irregularities, viz. dry spraying, weld seams, barnacle fouling and paint remains. A laboratory scale rotary set-up was used to determine the drag resistance, and the surface...

  19. The effect of a rotary heat exchanger in room-based ventilation on indoor humidity in existing apartments in temperate climates

    DEFF Research Database (Denmark)

    Smith, Kevin Michael; Svendsen, Svend

    2016-01-01

    The investigation constructed and simulated moisture balance equations for single-room ventilation with a non-hygroscopic rotary heat exchanger. Based on literature, the study assumed that all condensed moisture in the exhaust subsequently evaporated into the supply. Simulations evaluated...... the potential for moisture issues and compared results with recuperative heat recovery and whole-dwelling ventilation systems. To assess the sensitivity of results, the simulations used three moisture production schedules to represent possible conditions based on literature. The study also analyzed...... the sensitivity to influential parameters, such as infiltration rate, heat recovery, and indoor temperature. With a typical moisture production schedule, the rotary heat exchanger recovered excessive moisture from kitchens and bathrooms,which provided a mold risk. The rotary heat exchanger was only suitable...

  20. Rotary engine performance limits predicted by a zero-dimensional model

    Science.gov (United States)

    Bartrand, Timothy A.; Willis, Edward A.

    1992-01-01

    A parametric study was performed to determine the performance limits of a rotary combustion engine. This study shows how well increasing the combustion rate, insulating, and turbocharging increase brake power and decrease fuel consumption. Several generalizations can be made from the findings. First, it was shown that the fastest combustion rate is not necessarily the best combustion rate. Second, several engine insulation schemes were employed for a turbocharged engine. Performance improved only for a highly insulated engine. Finally, the variability of turbocompounding and the influence of exhaust port shape were calculated. Rotary engines performance was predicted by an improved zero-dimensional computer model based on a model developed at the Massachusetts Institute of Technology in the 1980's. Independent variables in the study include turbocharging, manifold pressures, wall thermal properties, leakage area, and exhaust port geometry. Additions to the computer programs since its results were last published include turbocharging, manifold modeling, and improved friction power loss calculation. The baseline engine for this study is a single rotor 650 cc direct-injection stratified-charge engine with aluminum housings and a stainless steel rotor. Engine maps are provided for the baseline and turbocharged versions of the engine.

  1. Theoretical Foundation for Electric-Dipole-Allowed Chiral-Specific Fluorescence Optical Rotary Dispersion (F-ORD) from Interfacial Assemblies.

    Science.gov (United States)

    Deng, Fengyuan; Ulcickas, James R W; Simpson, Garth J

    2016-11-03

    Fluorescence optical rotary dispersion (F-ORD) is proposed as a novel chiral-specific and interface-specific spectroscopic method. F-ORD measurements of uniaxial assemblies are predicted to be fully electric-dipole-allowed, with corresponding increases in sensitivity to chirality relative to chiral-specific measurements in isotropic assemblies that are commonly interpreted through coupling between electric and magnetic dynamic dipoles. Observations of strong chiral sensitivity in prior single-molecule fluorescence measurements of chiral interfacial molecules are in excellent qualitative agreement with the predictions of the F-ORD mechanism and challenging to otherwise explain. F-ORD may provide methods to suppress background fluorescence in studies of biological interfaces, as the detected signal requires both polar local order and interfacial chirality. In addition, the molecular-level descriptions of the mechanisms underpinning F-ORD may also potentially apply to aid in interpreting chiral-specific Raman and surface-enhanced Raman spectroscopy measurements of uniaxially oriented assemblies, opening up opportunities for chiral-specific and interface-specific vibrational spectroscopy.

  2. PREPP [Process Experimental Pilot Plant] rotary kiln seals: Problem and resolution

    International Nuclear Information System (INIS)

    Drexler, R.L.

    1990-01-01

    The Process Experimental Pilot Plant (PREPP) is a facility designed to demonstrate processing of low level chemical and transuranic hazardous waste. The plant includes equipment for handling the incoming waste containers, shredding, incineration and cooling the waste, grouting the residue and scrubbing and filtration of the off gas. The process incinerator is a rotary kiln approximately 8-1/2 ft diameter and 25 ft long with a rotary seal assembly at each end. Each seal assembly consists of a primary, secondary and tertiary seal, with a positive air pressure between primary and secondary seals to prevent out-leakage from the kiln. The kiln operates at 0.5 inch water negative pressure. From the very outset the kiln seals exhibited excessive drag which taxed the kiln drive capacity and excessive in-leakage which limited kiln temperature. An engineering evaluation concluded that the original seals supplied by the kiln vendor could not accommodate expansion and centerline shift of the kiln resulting from heatup of the kiln and its support system. A totally new concept kiln seal design has been generated to replace the (modified) original seals. This new seal system has been designed to provide a very tight long lasting seal which will accommodate the 1.5 inch axial shift and up to 1 inch radial movement of the kiln shell. Design lifetime of the seal is 10,000 operating hours between major maintenance services while maintaining an acceptable leak rate hot or cold, rotating or stopped. The design appears adaptable to any size kiln and is suitable for retrofit to existing kilns. A one-third scale prototype seal assembly is being built to verify the concept prior to construction of the 10 ft diameter seals for the PREPP rotary kiln. 4 figs

  3. The contact heat transfer between the heating plate and granular materials in rotary heat exchanger under overloaded condition

    Directory of Open Access Journals (Sweden)

    Luanfang Duan

    2018-03-01

    Full Text Available In the present work, the contact heat transfer between the granular materials and heating plates inside plate rotary heat exchanger (PRHE was investigated. The heat transfer coefficient is dominated by the contact heat transfer coefficient at hot wall surface of the heating plates and the heat penetration inside the solid bed. A plot scale PRHE with a diameter of Do = 273 mm and a length of L = 1000 mm has been established. Quartz sand with dp = 2 mm was employed as the experimental material. The operational parameters were in the range of ω = 1 – 8 rpm, and F = 15, 20, 25, 30%, and the effect of these parameters on the time-average contact heat transfer coefficient was analyzed. The time-average contact heat transfer coefficient increases with the increase of rotary speed, but decreases with the increase of the filling degree. The measured data of time-average heat transfer coefficients were compared with theoretical calculations from Schlünder’s model, a good agreement between the measurements and the model could be achieved, especially at a lower rotary speed and filling degree level. The maximum deviation between the calculated data and the experimental data is approximate 10%. Keywords: Rotary heat exchanger, Contact heat transfer, Granular material, Heating plate, Overloaded

  4. Apically extruded dentin debris by reciprocating single-file and multi-file rotary system.

    Science.gov (United States)

    De-Deus, Gustavo; Neves, Aline; Silva, Emmanuel João; Mendonça, Thais Accorsi; Lourenço, Caroline; Calixto, Camila; Lima, Edson Jorge Moreira

    2015-03-01

    This study aims to evaluate the apical extrusion of debris by the two reciprocating single-file systems: WaveOne and Reciproc. Conventional multi-file rotary system was used as a reference for comparison. The hypotheses tested were (i) the reciprocating single-file systems extrude more than conventional multi-file rotary system and (ii) the reciprocating single-file systems extrude similar amounts of dentin debris. After solid selection criteria, 80 mesial roots of lower molars were included in the present study. The use of four different instrumentation techniques resulted in four groups (n = 20): G1 (hand-file technique), G2 (ProTaper), G3 (WaveOne), and G4 (Reciproc). The apparatus used to evaluate the collection of apically extruded debris was typical double-chamber collector. Statistical analysis was performed for multiple comparisons. No significant difference was found in the amount of the debris extruded between the two reciprocating systems. In contrast, conventional multi-file rotary system group extruded significantly more debris than both reciprocating groups. Hand instrumentation group extruded significantly more debris than all other groups. The present results yielded favorable input for both reciprocation single-file systems, inasmuch as they showed an improved control of apically extruded debris. Apical extrusion of debris has been studied extensively because of its clinical relevance, particularly since it may cause flare-ups, originated by the introduction of bacteria, pulpal tissue, and irrigating solutions into the periapical tissues.

  5. Shape-memory materials as a working substance for martensitic rotary engines

    Science.gov (United States)

    Mandzhavidze, A. G.; Barnov, V. A.; Sobolevskaya, S. V.; Margvelashvili, O. V.

    2006-05-01

    A martensitic rotary engine has been designed. The physical properties of its working substance are studied, and the power characteristics of the engine are determined. Temperature and stress cycling are shown to adversely affect the properties of the working element (a coil spring made of titanium nickelide) and, thus, to decrease the engine efficiency.

  6. Effect of Frequency and Spatial-Harmonics on Rotary and Linear Induction Motor Characteristics

    Science.gov (United States)

    1972-03-01

    A computer analysis is made of the effect of current and MMF airgap harmonics on the output characteristics of rotary and linear induction motors. The current harmonics accompanying thyristor-control operation are evaluated by Fourier analyzing the p...

  7. Effect of Air Cleaning Technologies in Conjunction With the Use of Rotary Heat Exchangers in Residential Buildings

    DEFF Research Database (Denmark)

    Afshari, Alireza; Bergsøe, Niels Christian; Ekberg, Lars

    2013-01-01

    This study is part of a research project concerning the possibilities of applying efficient air cleaning technologies using rotary heat exchanger in residential buildings. The purpose of this project was to identify and adapt new air-cleaning technologies for implementation in HVAC systems...... with rotary air-to-air heat exchangers. For this purpose, a mechanical filter with low pressure drop and a 4 cm thick activated carbon filter were selected for testing in a laboratory environment. The measurements included testing of the filters, separately and combined, in a ductwork to study the efficiency...

  8. Baseline Design Compliance Matrix for the Rotary Mode Core Sampling System

    International Nuclear Information System (INIS)

    LECHELT, J.A.

    2000-01-01

    The purpose of the design compliance matrix (DCM) is to provide a single-source document of all design requirements associated with the fifteen subsystems that make up the rotary mode core sampling (RMCS) system. It is intended to be the baseline requirement document for the RMCS system and to be used in governing all future design and design verification activities associated with it. This document is the DCM for the RMCS system used on Hanford single-shell radioactive waste storage tanks. This includes the Exhauster System, Rotary Mode Core Sample Trucks, Universal Sampling System, Diesel Generator System, Distribution Trailer, X-Ray Cart System, Breathing Air Compressor, Nitrogen Supply Trailer, Casks and Cask Truck, Service Trailer, Core Sampling Riser Equipment, Core Sampling Support Trucks, Foot Clamp, Ramps and Platforms and Purged Camera System. Excluded items are tools such as light plants and light stands. Other items such as the breather inlet filter are covered by a different design baseline. In this case, the inlet breather filter is covered by the Tank Farms Design Compliance Matrix

  9. Comparison of quality of obturation and instrumentation time using hand files and two rotary file systems in primary molars: A single-blinded randomized controlled trial.

    Science.gov (United States)

    Govindaraju, Lavanya; Jeevanandan, Ganesh; Subramanian, E M G

    2017-01-01

    In permanent dentition, different rotary systems are used for canal cleaning and shaping. Rotary instrumentation in pediatric dentistry is an emerging concept. A very few studies have compared the efficiency of rotary instrumentation for canal preparation in primary teeth. Hence, this study was performed to compare the obturation quality and instrumentation time of two rotary files systems - Protaper, Mtwo with hand files in primary molars. Forty-five primary mandibular molars were randomly allotted to one of the three groups. Instrumentation was done using K-files in Group 1; Protaper in Group 2; and Mtwo in Group 3. Instrumentation time was recorded. The canal filling quality was assessed as underfill, optimal fill, and overfill. Statistical analysis was done using Chi-square, ANOVA, and post hoc Tukey test. No significant difference was observed in the quality of obturation among three groups. Intergroup comparison of the instrumentation time showed a statistically significant difference between the three groups. The use of rotary instrumentation in primary teeth results in marked reduction in the instrumentation time and improves the quality of obturation.

  10. Operability test procedure for the Rotary Mode Core Sampling System Exhausters 3 and 4

    International Nuclear Information System (INIS)

    WSaldo, E.J.

    1995-01-01

    This document provides a procedure for performing operability testing of the Rotary Mode Core Sampling System Exhausters 3 ampersand 4. Upon completion of testing activities an operability testing report will be issued

  11. Development of a Rotary Engine Powered APU for a Medium Duty Hybrid Shuttle Bus

    National Research Council Canada - National Science Library

    McBroom, Scott

    1998-01-01

    Under contract to the TARDEC Petroleum and Water Business Area, sponsored by the Defense Advanced Research Projects Agency, SwRI has procured and installed a rotary Auxiliary Power Unit on a medium...

  12. Postoperative quality of life following single-visit root canal treatment performed by rotary or reciprocating instrumentation: a randomized clinical trial.

    Science.gov (United States)

    Pasqualini, D; Corbella, S; Alovisi, M; Taschieri, S; Del Fabbro, M; Migliaretti, G; Carpegna, G C; Scotti, N; Berutti, E

    2016-11-01

    To compare the impact of rotary and reciprocating instrumentation on postoperative quality of life (POQoL) after single-visit primary root canal treatment. A randomized controlled clinical trial was designed and carried out in a University endodontic practice in northern Italy. Healthy subjects with asymptomatic irreversible pulpitis, symptomatic irreversible pulpitis or pulp necrosis with or without apical periodontitis (symptomatic or asymptomatic) scheduled for primary root canal treatment were enrolled. Single-visit root canal treatment was performed with ProTaper ™ S1-S2-F1-F2 (rotary group, n = 23) and WaveOne ™ Primary (reciprocating group, n = 24). Irrigation was performed with 5% NaOCl and 10% EDTA. Root canal filling was performed with the continuous-wave technique and ZOE sealer. POQoL indicators were evaluated for 7 days post-treatment. The variation of each indicator over time was compared using anova for repeated measures (P rotary group (mean, P = 0.077; maximum, P = 0.015). Difficulty in eating (P = 0.017), in performing daily activities (P = 0.023), in sleeping (P = 0.021) and in social relations (P = 0.077), was more evident in the reciprocating group. Patients' perception of the impact of treatment on POQoL was more favourable in the rotary group (P = 0.006). Multirooted tooth type and pre-existing periradicular inflammation were associated with a decrease in POQoL. Reciprocating instrumentation affected POQoL to a greater extent than rotary instrumentation. © 2015 International Endodontic Journal. Published by John Wiley & Sons Ltd.

  13. The application of cast SiC/Al to rotary engine components

    Science.gov (United States)

    Stoller, H. M.; Carluccio, J. R.; Norman, J. P.

    1986-01-01

    A silicon carbide reinforced aluminum (SiC/Al) material fabricated by Dural Aluminum Composites Corporation was tested for various components of rotary engines. Properties investigated included hardness, high temperature strength, wear resistance, fatigue resistance, thermal conductivity, and expansion. SiC/Al appears to be a viable candidate for cast rotors, and may be applicable to other components, primarily housings.

  14. The influence of the vane on the lubrication characteristics between the vane and the rolling piston of a rotary compressor

    International Nuclear Information System (INIS)

    Cho, Ihn Sung; Jung, Jae Youn

    2006-01-01

    The rolling piston type rotary compressor has been widely used for refrigeration and air -conditioning systems due to its compactness and high-speed operation. The present analysis is part of a research program directed toward maximizing the advantages of refrigerant compressors. The study of lubrication characteristics in the critical sliding component is essential for the design of refrigerant compressors. Therefore, theoretical investigation of the lubrication characteristics of a rotary compressor being used for refrigeration and air-conditioning systems was investigated. The Newton-Raphson method was used for a partial elastohydrodynamic lubrication analysis between the vane and the rolling piston of a rotary compressor. The results demonstrated that the vane thickness and the center line position of the vane significantly influenced the friction force and the energy loss between the vane and the rolling piston

  15. Comparison of fracture and deformation in the rotary endodontic instruments: Protaper versus K-3 system.

    Science.gov (United States)

    Nagi, Sana Ehsen; Khan, Farhan Raza; Rahman, Munawar

    2016-03-01

    This experimental study was done on extracted human teeth to compare the fracture and deformation of the two rotary endodontic files system namely K-3 and Protapers. It was conducted at the dental clinics of the Aga Khan University Hospital, Karachi, A log of file deformation or fracture during root canal preparation was kept. The location of fracture was noted along with the identity of the canal in which fracture took place. The fracture in the two rotary systems was compared. SPSS 20 was used for data analysis. Of the 172(80.4%) teeth possessing more than 15 degrees of curvature, fracture occurred in 7(4.1%) cases and deformation in 10(5.8%). Of the 42(19.6%) teeth possessing less than 15 degrees of curvature, fracture occurred in none of them while deformation was seen in 1(2.4%). There was no difference in K-3 and Protaper files with respect to file deformation and fracture. Most of the fractures occurred in mesiobuccal canals of maxillary molars, n=3(21.4%). The likelihood of file fracture increased 5.65-fold when the same file was used more than 3 times. Irrespective of the rotary system, apical third of the root canal space was the most common site for file fracture.

  16. A comparative evaluation of cleaning efficacy (debris and smear layer removal) of hand and two NiTi rotary instrumentation systems (K3 and ProTaper): a SEM study.

    Science.gov (United States)

    Reddy, K Balakoti; Dash, Shreemoy; Kallepalli, Sowmya; Vallikanthan, Sangeetha; Chakrapani, N; Kalepu, Vamsi

    2013-11-01

    The present study was conducted to compare the cleaning efficacy (debris and smear layer removal) of hand and two NiTi rotary instrumentation systems (K3 and ProTaper). Sixty single rooted human maxillary anterior teeth decoronated at the cementoenamel junction were used. All the specimens were divided into four groups of 15 teeth each, group I--ProTaper rotary instrumentation done, group II--K3 rotary instrumentation done, group III--Stainless steel K-file instrumentation done, group IV--root canal irrigation without instrumentation. Root canal preparation was done in a crown down manner and 3% sodium hypochlorite was used as irrigant after each file followed by final rinse with 5 ml of 17% EDTA solution, then specimens were scanning electron microscopic (SEM) examination. Statistical analysis was done using one-way ANOVA followed by post hoc Tukey's HSD test. Group I showed highly statistical significant difference compared to other groups. There was no statistically significant difference considering smear layer at any levels among the groups with no smear layer formation in group IV. ProTaper rotary instrumentation showed the maximum cleaning efficacy followed by K3 rotary instrumentation in the coronal, middle and apical thirds of the root canal. ProTaper rotary instruments are more efficient than hand and K3 rotary instruments during root canal treatment.

  17. Micro-computed tomographic comparison of nickel-titanium rotary versus traditional instruments in C-shaped root canal system.

    Science.gov (United States)

    Yin, Xingzhe; Cheung, Gary Shun-Pan; Zhang, Chengfei; Masuda, Yoshiko Murakami; Kimura, Yuichi; Matsumoto, Koukichi

    2010-04-01

    The purpose of this study was to assess the efficacy of instrumentation of C-shaped canals with ProTaper rotary system and traditional instruments by using micro-computed tomography (micro-CT). Twenty-four mandibular molars with C-shaped canals were selected in pairs and sorted equally into 2 groups, which were assigned for instrumentation by ProTaper rotary system (ProTaper group) or by K-files and Gates-Glidden burs (Hand Instrument group). Three-dimensional images were constructed by micro-CT. The volume of dentin removed, uninstrumented canal area, time taken for instrumentation, and iatrogenic error of instrumentation were investigated. Hand Instrument group showed greater amount of volumetric dentin removal and left less uninstrumented canal area than ProTaper group (P ProTaper group than for Hand Instrument group (P Hand Instrument group than for ProTaper group. It was concluded that ProTaper rotary system maintained the canal curvature with speediness and few procedural errors, whereas traditional instrumentation can clean more canal surface. Copyright (c) 2010 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  18. Comparison of directly compressed vitamin B12 tablets prepared from micronized rotary-spun microfibers and cast films.

    Science.gov (United States)

    Sebe, István; Bodai, Zsolt; Eke, Zsuzsanna; Kállai-Szabó, Barnabás; Szabó, Péter; Zelkó, Romána

    2015-01-01

    Fiber-based dosage forms are potential alternatives of conventional dosage forms from the point of the improved extent and rate of drug dissolution. Rotary-spun polymer fibers and cast films were prepared and micronized in order to direct compress after homogenization with tabletting excipients. Particle size distribution of powder mixtures of micronized fibers and films homogenized with tabletting excipients were determined by laser scattering particle size distribution analyzer. Powder rheological behavior of the mixtures containing micronized fibers and cast films was also compared. Positron annihilation lifetime spectroscopy was applied for the microstructural characterization of micronized fibers and films. The water-soluble vitamin B12 release from the compressed tablets was determined. It was confirmed that the rotary spinning method resulted in homogeneous supramolecularly ordered powder mixture, which was successfully compressed after homogenization with conventional tabletting excipients. The obtained directly compressed tablets showed uniform drug release of low variations. The results highlight the novel application of micronized rotary-spun fibers as intermediate for further processing reserving the original favorable powder characteristics of fibrous systems.

  19. Comparative evaluation of apical extrusion of bacteria using hand and rotary systems : An in vitro study

    Science.gov (United States)

    Ghivari, Sheetal B; Kubasad, Girish C; Deshpande, Preethi

    2012-01-01

    Aim: To evaluate the bacteria extruded apically during root canal preparation using two hand and rotary instrumentation techniques. Materials and Methods: Eighty freshly extracted mandibular premolars were mounted in bacteria collection apparatus. Root canals were contaminated with the pure culture of Enterococcus fecalis (ATCC 29212) and dried at 37°C for 24 h. Bacteria extruded were collected, incubated in brain heart infusion agar for 24 h at 36°C and the colony forming units (CFU) were counted. Statistical Analysis: The mean number of colony forming units were calculated by One-way ANOVA and comparison between the groups made by multiple comparison (Dunnet D) test. Results: The step-back technique extruded highest number of bacteria in comparison to other hand and rotary Ni–Ti systems. Conclusion: Under the limitation of this study all hand and rotary instrumentation techniques extruded bacteria. Among all the instrumentation techniques step-back technique extruded more number of bacteria and K-3 system the least. Further in vivo research in this direction could provide more insight into the biologic factors associated and focus on bacterial species that essentially play a major role in post instrumentation flare-ups. PMID:22368332

  20. Outside corner and method of making in the making lead brick (plain brick) using rotary table

    International Nuclear Information System (INIS)

    Muhammad Awwaluddin; Samuel Praptoyo

    2009-01-01

    It has been developed a tool that can be used for defining angles on the fabrication of lead bricks. The angles are both outside of the lead bricks that correspond to male and female shape respectively. The lead bricks should be in accordance to ISO 7212-1986 standard which has angle tolerance 90° 0 +15 for male and 90° 0 -15 for female. The accuracy of these angles is very important to maintain the equilibrium position of the bricks so that their arrangement will not lining or collapse. A rotary table is used for the fabrication to make easier in setting up any related working apparatus and to have precision measurement result. However, a lot of operator do not know yet how to operate such a rotary table to produce angle with such an eligible tolerance. Therefore, a method of measurement in machining lead brick process using a rotary table is necessarily required. This method will be used as a reference to have angle accuracy of 0,03° in producing outside and inside angles or male and female lead bricks. (author)

  1. Intraoperative discomfort associated with the use of a rotary or reciprocating system: a prospective randomized clinical

    Directory of Open Access Journals (Sweden)

    Aline Cristine Gomes

    2017-05-01

    Full Text Available Objectives The aim of this randomized, controlled, prospective clinical study was to evaluate patients' intraoperative discomfort during root canal preparations in which either multi-file rotary (Mtwo or single-file reciprocating (Reciproc systems were used. Materials and Methods Fifty-five adult patients, aged between 25 and 69 years old, with irreversible pulpitis or pulp necrosis participated in this study. Either the mesiobuccal or the distobuccal canals for maxillary molars and either the mesiobuccal or the mesiolingual canals for mandibular molars were randomly chosen to be instrumented with Mtwo multi-file rotary or Reciproc single-file reciprocating systems. Immediately after each canal instrumentation under anesthesia, patient discomfort was assessed using a 1 - 10 visual analog scale (VAS, ranging from ‘least possible discomfort’ (1 to ‘greatest possible discomfort’ (10. The Wilcoxon signed-rank test was used to determine significant differences at p< 0.05. Results Little intraoperative discomfort was found in all cases. No statistically significant differences in intraoperative discomfort between the 2 systems were found (p = 0.660. Conclusions Root canal preparation with multi-file rotary or single-file reciprocating systems had similar and minimal effects on patients' intraoperative discomfort.

  2. An in vitro comparison of apically extruded debris using three rotary nickel-titanium instruments

    Directory of Open Access Journals (Sweden)

    Tamer Tasdemir

    2010-09-01

    Conclusion: According to this study, all instrumentation techniques apically extruded debris through the apical foramen. However, the BioRaCe instruments induced less extruded debris than the ProTaper Universal and Mtwo rotary systems.

  3. Redesign Alat Las Gesek Rotari Dengan Pendekatan Fault Tree Analysis (FTA) Dan Design for Manufacture and Assembly (DFMA)

    OpenAIRE

    ', Ricky '; ', Yohanes '; Badri, Muftil '

    2016-01-01

    The FTA is a method to identify the failure of system. Whilst, the DFMA is a method to determine how to design of product, which is purposed to increases the quality of product and make easily the product assembly process. The rotary friction welding is one of type of friction welding, that principle is both of surfaces by friction which one end is fixed and then provides axial pressure to against another the rotating surface until both surface forge together. The Rotary friction welding mach...

  4. Australian Rotary Health: a major contributor to mental illness research and mental health awareness in Australia.

    Science.gov (United States)

    Jorm, Anthony; Sawyer, Michael; Gillett, Joy

    2012-08-01

    Australian Rotary Health (ARH) was established in 1981 with the goal of supporting family health research in Australia. Since 2000, ARH has supported research relevant to mental health and mental illness. This article describes the early history of the fund, the reasons for the move to mental illness research, some examples of research projects that have had a beneficial impact and the branching out into mental health community awareness raising and stigma reduction. ARH has emerged as a major non-government supporter of mental illness research. It has also effectively engaged Rotary clubs at a local level to increase community awareness of mental illness and to reduce stigma.

  5. Influence of axial movement on fatigue of ProFile Ni-Ti rotary instruments: an in vitro evaluation.

    Science.gov (United States)

    Avoaka, Marie-Chantal; Haïkel, Youssef

    2010-05-01

    The aim of this study was to evaluate the influence of the axial movement and the angle of curve (in degrees) on fatigue of nickel-titanium (Ni-Ti) ProFile rotary endodontic instruments. Ni-Ti ProFile rotary instruments (Maillefer SA, Ballaigues, Switzerland), 25 mm long in the range of ISO size 15 to 40 with two tapers (0.4 and 0.6) were evaluated. They are divided in two groups: the instruments with axial movement and those without axial movement. The system used to test the fatigue is maintained in mechanical conditions as close as possible to the clinical situation. The axial movement is in the order of 2 mm in corono-apical direction with a frequency of 1 Hz. The concave radii incorporating a notched V-form for guiding the instruments were: 5; 7,5 and 10 mm. The rotary system is mounted on an electric handpiece and rotated at 350 rpm speed as recommended by the manufacturers. The instruments are rotated until their separation, and the time, in seconds, is recorded. Statistical evaluation is undertaken using a two-way t-test to identify significant differences between variables in the study (p engine drive ProFile instruments incorporating an axial movement and the instruments without axial movement with the same radius of curvature, size and taper.The incorporation of the axial movement increases significantly the life-span of the ProFile rotary instruments. This should reduce the risk of the instrument separation during the endodontic treatment.

  6. Effects of ignition parameters on combustion process of a rotary engine fueled with natural gas

    International Nuclear Information System (INIS)

    Fan, Baowei; Pan, Jianfeng; Liu, Yangxian; Zhu, Yuejin

    2015-01-01

    Highlights: • A 3-D simulation model based on the chemical reaction kinetics is established. • The tumble near the trailing spark plug is beneficial for the combustion rate. • The best position of the trailing spark plug is at the rear of the tumble zone. • An increase of the tumble effect time can improve the combustion rate. • Considering the rate of pressure rise, the best ignition timing is 50 °CA (BTDC). - Abstract: The side-ported rotary engine fueled with natural gas is a new, clean, efficient energy system. This work aims to numerically study the performance, combustion and emission characteristics of a side-ported rotary engine fueled with natural gas under different ignition positions and ignition timings. Simulations were performed using multi-dimensional software ANASYS Fluent. On the basis of the software, a three-dimensional dynamic simulation model was established by writing dynamic mesh programs and choosing a detailed reaction mechanism. The three-dimensional dynamic simulation model, based on the chemical reaction kinetics, was also validated by the experimental data. Meanwhile, further simulations were then conducted to investigate how to impact the combustion process by the coupling function between ignition operating parameter and the flow field inside the cylinder. Simulation results showed that in order to improve the combustion efficiency, the trailing spark plug should be located at the rear of the tumble zone and the ignition timing should be advanced properly. This was mainly caused by the trailing spark plug being located at the rear of the tumble zone, as it not only allowed the fuel in the rear of combustion chamber to be burnt without delay, but also permitted the acceleration of the flame propagation by the tumble. Meanwhile, with advanced ignition timing, the time between ignition timing and the timing of the tumble disappearance increased, which led to an increase of the tumble effect time used to improve the combustion

  7. Effect of flue gas recirculation during oxy-fuel combustion in a rotary cement kiln

    International Nuclear Information System (INIS)

    Granados, David A.; Chejne, Farid; Mejía, Juan M.; Gómez, Carlos A.; Berrío, Ariel; Jurado, William J.

    2014-01-01

    The effect of Flue Gas Recirculation (FGR) during Oxy-Fuel Combustion in a Rotary Cement Kiln was analyzed by using a CFD model applied to coal combustion process. The CFD model is based on 3D-balance equations for mass, species, energy and momentum. Turbulence and radiation model coupled to a chemical kinetic mechanism for pyrolysis processes, gas–solid and gas–gas reactions was included to predicts species and flame temperature distribution, as well as convective and radiation energy fluxes. The model was used to study coal combustion with air and with oxygen for FGR between 30 and 85% as controller parameter for temperature in the process. Flame length effect and heat transfer by convection and radiation to the clinkering process for several recirculation ratios was studied. Theoretical studies predicted a located increase of energy flux and a reduction in flame length with respect to the traditional system which is based on air combustion. The impact of FGR on the oxy-fuel combustion process and different energy scenarios in cement kilns to increase energy efficiency and clinker production were studied and evaluated. Simulation results were in close agreement with experimental data, where the maximum deviation was 7%

  8. Rotary engine developments at Curtiss-Wright over the past 20 years and review of general aviation engine potential. [with direct chamber injection

    Science.gov (United States)

    Jones, C.

    1978-01-01

    The development of the rotary engine as a viable power plant capable of wide application is reviewed. Research results on the stratified charge engine with direct chamber injection are included. Emission control, reduced fuel consumption, and low noise level are among the factors discussed in terms of using the rotary engine in general aviation aircraft.

  9. Steering the motion of rotary solitons in radial lattices

    International Nuclear Information System (INIS)

    He, Y. J.; Malomed, Boris A.; Wang, H. Z.

    2007-01-01

    We demonstrate that rotary motion of a two-dimensional soliton trapped in a Bessel lattice can be precisely controlled by application of a finite-time push to the lattice, due to the transfer of the lattice's linear momentum to the orbital momentum of the soliton. A simple analytical consideration treating the soliton as a particle provides for an accurate explanation of numerical findings. Some effects beyond the quasi-particle approximation are explored too, such as destruction of the soliton by a hard push

  10. Advanced rotary engine components utilizing fiber reinforced Mg castings

    Science.gov (United States)

    Goddard, D.; Whitman, W.; Pumphrey, R.; Lee, C.-M.

    1986-01-01

    Under a two-phase program sponsored by NASA, the technology for producing advanced rotary engine components utilizing graphite fiber-reinforced magnesium alloy casting is being developed. In Phase I, the successful casting of a simulated intermediate housing was demonstrated. In Phase II, the goal is to produce an operating rotor housing. The effort involves generation of a material property data base, optimization of parameters, and development of wear- and corrosion-resistant cast surfaces and surface coatings. Results to date are described.

  11. Wave energy extraction by coupled resonant absorbers.

    Science.gov (United States)

    Evans, D V; Porter, R

    2012-01-28

    In this article, a range of problems and theories will be introduced that will build towards a new wave energy converter (WEC) concept, with the acronym 'ROTA' standing for resonant over-topping absorber. First, classical results for wave power absorption for WECs constrained to operate in a single degree of freedom will be reviewed and the role of resonance in their operation highlighted. Emphasis will then be placed on how the introduction of further resonances can improve power take-off characteristics by extending the range of frequencies over which the efficiency is close to a theoretical maximum. Methods for doing this in different types of WECs will be demonstrated. Coupled resonant absorbers achieve this by connecting a WEC device equipped with its own resonance (determined from a hydrodynamic analysis) to a new system having separate mass/spring/damper characteristics. It is shown that a coupled resonant effect can be realized by inserting a water tank into a WEC, and this idea forms the basis of the ROTA device. In essence, the idea is to exploit the coupling between the natural sloshing frequencies of the water in the internal tank and the natural resonance of a submerged buoyant circular cylinder device that is tethered to the sea floor, allowing a rotary motion about its axis of attachment.

  12. A magnetic fluid seal for rotary blood pumps: Long-term performance in liquid

    Science.gov (United States)

    Mitamura, Yoshinori; Takahashi, Sayaka; Amari, Shuichi; Okamoto, Eiji; Murabayashi, Shun; Nishimura, Ikuya

    A magnetic fluid (MF) seal enables mechanical contact-free rotation of the shaft and hence has excellent durability. The performance of a MF seal, however, has been reported to decrease in liquids. We have developed a MF seal that has a 'shield' mechanism and a new MF with a higher magnetization of 47.9 kA/m. The sealing performance of the MF seal installed in a rotary blood pump was studied. The seal was perfect against a pressure of 150 mmHg in a continuous flow of 4.0 L/min for 275 days and against a pressure of 175 mmHg in a continuous flow of 3.9 L/min for 217 days. We have developed a MF seal that works in liquid against pressure mostly used clinically. The magnetic fluid seal is promising as a shaft seal for rotary blood pumps.

  13. Effect of hydrogen addition on combustion and emissions performance of a gasoline rotary engine at part load and stoichiometric conditions

    International Nuclear Information System (INIS)

    Ji, Changwei; Su, Teng; Wang, Shuofeng; Zhang, Bo; Yu, Menghui; Cong, Xiaoyu

    2016-01-01

    Highlights: • The performance of a H_2-blended gasoline rotary engine was studied. • The p, Bmep, T_m_a_x and η_b increased after H_2 blending. • Both the CA0-10 and CA10-90 were shortened by the H_2 addition. • H_2 addition resulted in the reduced HC, CO and CO_2 emissions. - Abstract: The rotary engines may encounter high fuel consumption and emissions due to its narrow and long combustion chamber design. The low ignition energy and high flame speed of hydrogen may help improve the combustion of rotary engines. In this paper, a gasoline rotary engine equipped with gasoline and hydrogen injectors was developed to investigate the combustion and emissions of hydrogen-blended gasoline rotary engines. The engine was run at 3000 rpm and a manifolds absolute pressure of 37.5 kPa with the stoichiometric excess air ratio. The spark timing was set to be 25°CA before the top dead center. The engine was first fueled with the pure gasoline and then blended with the hydrogen. The hydrogen volume fractions in the intake were gradually increased from 0% to 5.2%. The results showed that the combustion pressure, brake mean effective pressure, cylinder temperature and thermal efficiency were simultaneously increased after the hydrogen blending. The crank angle of peak pressure was advanced with the hydrogen addition. The hydrogen enrichment was effective on reducing flame development and propagation periods. HC emissions were reduced by 44.8% when the hydrogen volume fraction in the intake was raised from 0% to 5.2%, CO and CO_2 emissions were also reduced after the hydrogen blending.

  14. Movement kinematics and cyclic fatigue of NiTi rotary instruments: a systematic review.

    Science.gov (United States)

    Ferreira, F; Adeodato, C; Barbosa, I; Aboud, L; Scelza, P; Zaccaro Scelza, M

    2017-02-01

    The aim of this review was to provide a detailed analysis of the literature concerning the correlation between different movement kinematics and the cyclic fatigue resistance of NiTi rotary endodontic instruments. From June 2014 to August 2015, four independent reviewers comprehensively and systematically searched the Medline (PubMed), EMBASE, Web of Science, Scopus and Google Scholar databases for works published since January 2005, using the following search terms: endodontics; nickel-titanium rotary files; continuous rotation; reciprocating motion; cyclic fatigue. In addition to the electronic searches, manual searches were performed to include articles listed in the reference sections of high-impact published articles that were not indexed in the databases. Laboratory studies in English language were considered for this review. The electronic and manual searches resulted in identification of 75 articles. Based on the inclusion criteria, 32 articles were selected for analysis of full-text copies. Specific analysis was then made of 20 articles that described the effects of reciprocating and continuous movements on cyclic fatigue of the instruments. A wide range of testing conditions and methodologies have been used to compare the cyclic fatigue resistance of rotary endodontic instruments. Most studies report that reciprocating motion improves the fatigue resistance of endodontic instruments, compared to continuous rotation, independent of other variables such as the speed of rotation, the angle or radius of curvature of simulated canals, geometry and taper, or the surface characteristics of the NiTi instruments. © 2016 International Endodontic Journal. Published by John Wiley & Sons Ltd.

  15. Environmental impact of incineration of calorific industrial waste: rotary kiln vs. cement kiln.

    Science.gov (United States)

    Vermeulen, Isabel; Van Caneghem, Jo; Block, Chantal; Dewulf, Wim; Vandecasteele, Carlo

    2012-10-01

    Rotary kiln incinerators and cement kilns are two energy intensive processes, requiring high temperatures that can be obtained by the combustion of fossil fuel. In both processes, fossil fuel is often substituted by high or medium calorific waste to avoid resource depletion and to save costs. Two types of industrial calorific waste streams are considered: automotive shredder residue (ASR) and meat and bone meal (MBM). These waste streams are of current high interest: ASR must be diverted from landfill, while MBM can no longer be used for cattle feeding. The environmental impact of the incineration of these waste streams is assessed and compared for both a rotary kiln and a cement kiln. For this purpose, data from an extensive emission inventory is applied for assessing the environmental impact using two different modeling approaches: one focusing on the impact of the relevant flows to and from the process and its subsystems, the other describing the change of environmental impact in response to these physical flows. Both ways of assessing emphasize different aspects of the considered processes. Attention is paid to assumptions in the methodology that can influence the outcome and conclusions of the assessment. It is concluded that for the incineration of calorific wastes, rotary kilns are generally preferred. Nevertheless, cement kilns show opportunities in improving their environmental impact when substituting their currently used fuels by more clean calorific waste streams, if this improvement is not at the expense of the actual environmental impact. Copyright © 2012 Elsevier Ltd. All rights reserved.

  16. A study of the displacement of a Wankel rotary engine

    Science.gov (United States)

    Beard, J. E.; Pennock, G. R.

    1993-03-01

    The volumetric displacement of a Wankel rotary engine is a function of the trochoid ratio and the pin size ratio, assuming the engine has a unit depth and the number of lobes is specified. The mathematical expression which defines the displacement contains a function which can be evaluated directly and a normal elliptic integral of the second type which does not have an explicit solution. This paper focuses on the contribution of the elliptic integral to the total displacement of the engine. The influence of the elliptic integral is shown to account for as much as 20 percent of the total displacement, depending on the trochoid ratio and the pin size ratio. Two numerical integration techniques are compared in the paper, namely, the trapezoidal rule and Simpson's 1/3 rule. The bounds on the error, associated with each numerical method, are analyzed. The results indicate that the numerical method has a minimal effect on the accuracy of the calculated displacement for a practical number of integration steps. The paper also evaluates the influence of manufacturing tolerances on the calculated displacement and the actual displacement. Finally. a numerical example of the common three-lobed Wankel rotary engine is included for illustrative purposes.

  17. Experimental calibration of forward and inverse neural networks for rotary type magnetorheological damper

    DEFF Research Database (Denmark)

    Bhowmik, Subrata; Weber, Felix; Høgsberg, Jan Becker

    2013-01-01

    This paper presents a systematic design and training procedure for the feed-forward backpropagation neural network (NN) modeling of both forward and inverse behavior of a rotary magnetorheological (MR) damper based on experimental data. For the forward damper model, with damper force as output...

  18. Synthesis of Dynamically Balanced Mechanisms by Using Counter-Rotary Countermass Balanced Double Pendula

    NARCIS (Netherlands)

    van der Wijk, V.; Herder, Justus Laurens

    2009-01-01

    Complete dynamic balancing principles still cannot avoid a substantial increase in mass and inertia. In addition, the conditions for dynamic balance and inertia equations can be complicated to derive. This article shows how a double pendulum, which is fully dynamically balanced using counter-rotary

  19. Clinical and Radiographic Evaluation of Procedural Errors during Preparation of Curved Root Canals with Hand and Rotary Instruments: A Randomized Clinical Study

    Science.gov (United States)

    Khanna, Rajesh; Handa, Aashish; Virk, Rupam Kaur; Ghai, Deepika; Handa, Rajni Sharma; Goel, Asim

    2017-01-01

    Background: The process of cleaning and shaping the canal is not an easy goal to obtain, as canal curvature played a significant role during the instrumentation of the curved canals. Aim: The present in vivo study was conducted to evaluate procedural errors during the preparation of curved root canals using hand Nitiflex and rotary K3XF instruments. Materials and Methods: Procedural errors such as ledge formation, instrument separation, and perforation (apical, furcal, strip) were determined in sixty patients, divided into two groups. In Group I, thirty teeth in thirty patients were prepared using hand Nitiflex system, and in Group II, thirty teeth in thirty patients were prepared using K3XF rotary system. The evaluation was done clinically as well as radiographically. The results recorded from both groups were compiled and put to statistical analysis. Statistical Analysis: Chi-square test was used to compare the procedural errors (instrument separation, ledge formation, and perforation). Results: In the present study, both hand Nitiflex and rotary K3XF showed ledge formation and instrument separation. Although ledge formation and instrument separation by rotary K3XF file system was less as compared to hand Nitiflex. No perforation was seen in both the instrument groups. Conclusion: Canal curvature played a significant role during the instrumentation of the curved canals. Procedural errors such as ledge formation and instrument separation by rotary K3XF file system were less as compared to hand Nitiflex. PMID:29042727

  20. Clinical Evaluation of Quality of Obturation and Instrumentation Time using Two Modified Rotary File Systems with Manual Instrumentation in Primary Teeth.

    Science.gov (United States)

    Govindaraju, Lavanya; Jeevanandan, Ganesh; Subramanian, Emg

    2017-09-01

    Pulp therapy in primary teeth has been performed using various instrumentation techniques. However, the conventional instrumentation technique used for root canal preparation in primary teeth is hand instrumentation. Various Nickel-Titanium (Ni-Ti) instruments are available to perform efficient root canal preparation in primary teeth. These Ni-Ti instruments has been designed to aid in better root canal preparation in permanent teeth but are rarely used in primary teeth. It is necessary to assess the feasibility of using these adult rotary files with a modified sequence in primary teeth. To compare the quality of obturation and instrumentation time during root canal preparation using hand files and modified rotary file systems in primary molars. Forty-five primary mandibular molars were randomly assigned to three experimental groups (n=15). Group I was instrumented using k-hand files, Group II with S2 ProTaper universal file and Group III with 0.25 tip 4% taper K3 rotary file. Standardized digital radiographs were taken before and after root canal instrumentation. Root canal preparation time was also recorded. Statistical analysis of the obtained data was done using SPSS Software version 17.0. An intergroup comparison of the instrumentation time and the quality of obturation was done using ANOVA and Chi-square test with the level of significance set at 0.05. No significant differences were noted with regard to the quality of obturation (p=0.791). However, a statistically significant difference was noted in the instrumentation time between the three groups (pProTaper rotary system had significantly lesser instrumentation time when compared to that of K3 rotary system and hand file system. The hand files, S2 ProTaper Universal and K3 0.25 tip 4% taper files systems performed similarly with respect to the quality of obturation. There was a significant difference in instrumentation time with manual instrumentation compared to the modified rotary file systems in primary

  1. A mechanical energy harvested magnetorheological damper with linear-rotary motion converter

    Science.gov (United States)

    Chu, Ki Sum; Zou, Li; Liao, Wei-Hsin

    2016-04-01

    Magnetorheological (MR) dampers are promising to substitute traditional oil dampers because of adaptive properties of MR fluids. During vibration, significant energy is wasted due to the energy dissipation in the damper. Meanwhile, for conventional MR damping systems, extra power supply is needed. In this paper, a new energy harvester is designed in an MR damper that integrates controllable damping and energy harvesting functions into one device. The energy harvesting part of this MR damper has a unique mechanism converting linear motion to rotary motion that would be more stable and cost effective when compared to other mechanical transmissions. A Maxon motor is used as a power generator to convert the mechanical energy into electrical energy to supply power for the MR damping system. Compared to conventional approaches, there are several advantages in such an integrated device, including weight reduction, ease in installation with less maintenance. A mechanical energy harvested MR damper with linear-rotary motion converter and motion rectifier is designed, fabricated, and tested. Experimental studies on controllable damping force and harvested energy are performed with different transmissions. This energy harvesting MR damper would be suitable to vehicle suspensions, civil structures, and smart prostheses.

  2. Spiral computed tomography assessment of the efficacy of different rotary versus hand retreatment system.

    Science.gov (United States)

    Mittal, Neelam; Jain, Jyoti

    2014-01-01

    The purpose of this study was to evaluate the efficacy of nickel-titanium rotary retreatment systems versus stainless steel hand retreatment system with or without solvent for gutta-percha removal during retreatment. Sixty extracted human mandibular molar teeth with single canal in a distal root was prepared with ProTaper rotary nickel-titanium files and obturated with gutta-percha and sealer. The teeth were randomly divided into six groups of 10 specimens in each groups. The volume of filling material before and after retreatment were evaluated in cm(3) using the computed tomography (CT) scanner proprietary software. Maximum amount of filling material removed during retreatment with ProTaper retreatment system with solvent and minimum with hand retreatment system with solvent. None of the technique was 100% effective in removing the filling materials, but the ProTaper retreatment system with solvent was better.

  3. MECHANISMS GOVERNING TRANSIENTS FROM THE BATCH INCINERATION OF LIQUID WASTES IN ROTARY KILNS

    Science.gov (United States)

    When "containerized" liquid wastes, bound on sorbents. are introduced into a rotary kiln in a batch mode, transient phenomena in-volving heat transfer into, and waste mass transfer out of, the sorbent can oromote the raoid release of waste vaoor into the kiln environment. This ra...

  4. Influence of multiple clinical use on fatigue resistance of ProTaper rotary nickel-titanium instruments.

    Science.gov (United States)

    Vieira, E P; França, E C; Martins, R C; Buono, V T L; Bahia, M G A

    2008-02-01

    To examine the influence of clinical use on the occurrence of deformation and fracture and on the fatigue resistance of ProTaper rotary instruments. Root canal treatments were performed on patients using the ProTaper rotary system. Ten sets of instruments were used by an experienced endodontist, each set in five molars. Another 10 sets of instruments were used by the same operator, each set in eight molars. In addition, 10 sets of instruments were used, each set in five molars, by undergraduate students with no clinical experience with the system. After clinical use, S1, S2, F1 and F2 instruments were analysed for damage by optical and scanning electron microscopy. The used sets, along with a control group of 12 sets of new instruments, were then tested in a bench device for fatigue resistance. The use of the ProTaper rotary instruments by an experienced endodontist allowed for the cleaning and shaping of the root canal system of up to eight molars without fracture. During the students work, six instruments fractured. Fatigue resistance decreased upon clinical use for all instruments analysed. Fatigue resistance of used instruments was reduced, but no significant change was observed amongst the instruments used for shaping the canals of five and eight molars. Operator experience affected the occurrence of fracture and plastic deformation during shaping.

  5. Effect of canal preparation with TRUShape and Vortex rotary instruments on three-dimensional geometry of oval root canals.

    Science.gov (United States)

    Arias, Ana; Paqué, Frank; Shyn, Stephanie; Murphy, Sarah; Peters, Ove A

    2018-04-01

    The purpose of this study was to assess the geometry of non-round root canals after preparation with TRUShape (a novel instrument with s-shaped longitudinal design) in comparison to conventional rotary instrumentation using micro-computed tomography. Twenty distal root canals of mandibular molars were randomly distributed in two groups to be shaped with either TRUShape or Vortex rotaries. Percentages of unprepared surface and volume of dentin removal for the entire canal and for the apical 4 mm were calculated. Canal transportation and the structure model index (SMI) were assessed. Data were compared with Student t-tests. Shaping with both techniques resulted in similar prepared surface and volume of dentin removed, as well as the extent of canal transportation. The SMI shape factor was significantly lower for TRUShape preparations (P = 0.04) suggesting less rounding during rotary preparation. Although both instruments were suitable for the preparation of oval canals, TRUShape appeared to better conform to the original ribbon-shaped anatomy. © 2017 Australian Society of Endodontology Inc.

  6. Engineering task plan for rotary mode core sampling exhausters CAM high radiation interlock

    International Nuclear Information System (INIS)

    BOGER, R.M.

    1999-01-01

    The Rotary Mode Core Sampling (RMCS) system is primarily made up of the Rotary Mode Core Sample Trucks (RMCST) and the RMCS Exhausters. During RMCS operations an Exhauster is connected to a tank riser and withdraws gases from the tank dome vapor space at approximately 200 Standard Cubic Feet per Minute (SCFM). The gases are passed through two High Efficiency Particulate Air (HEPA) filters before passing out the exhaust stack to the atmosphere. A Continuous Air Monitor (CAM) monitors the exhaust gases in the exhaust stack for beta particle and gamma radiation. The CAM has a high radiation alarm output and a detector fail alarm output. The CAM alarms are currently connected to the data logger only. The CAM alarms require operator response per procedure LMHC 1998 but no automatic functions are initiated by the CAM alarms. Currently, there are three events that can cause an automatic shut down of the Exhauster. These are, Low Tank Pressure, Highnow Stack Flow and High HEPA Filter Differential Pressure (DP)

  7. Influence of Axial Movement on Fatigue of Profile® Ni-Ti Rotary Instruments: an in vitro evaluation

    Directory of Open Access Journals (Sweden)

    Marie-Chantal Avoaka

    2010-05-01

    Full Text Available The aim of this study was to evaluate the influence of the axial movement and the angle of curve (in degrees on fatigue of nickel-titanium (Ni-Ti ProFile’ rotary endodontic instruments.Ni-Ti ProFile’ rotary instruments (Maillefer SA, Ballaigues, Switzerland, 25 mm long in the range of ISO size 15 to 40 with two tapers (0.4 and 0.6 were evaluated. They are divided in two groups: the instruments with axial movement and those without axial movement. The system used to test the fatigue is maintained in mechanical conditions as close as possible to the clinical situation. The axial movement is in the order of 2mm in corono-apical direction with a frequency of 1Hz. The concave radii incorporating a notched V-form for guiding the instruments were: 5; 7,5 and 10 mm. The rotary system is mounted on an electric handpiece and rotated at 350 rpm speed as recommended by the manufacturers. The instruments are rotated until their separation, and the time, in seconds, is recorded. Statístícal evaluation is undertaken using a two-way t-test to identify significant differences between variables in the study (p <0,05.We found significant statistical difference (p<0,05 between Ni-Ti engine drive ProFile’ instruments incorporating an axial movement and the instruments without axial movement with the same radius of curvature, size and taper.The incorporation of the axial movement increases significantly the life-span of the ProFile’ rotary instruments. This should reduce the risk of the instrument separation during the endodontic treatment

  8. Evaluation of Root Canal Preparation Using Rotary System and Hand Instruments Assessed by Micro-Computed Tomography.

    Science.gov (United States)

    Stavileci, Miranda; Hoxha, Veton; Görduysus, Ömer; Tatar, Ilkan; Laperre, Kjell; Hostens, Jeroen; Küçükkaya, Selen; Muhaxheri, Edmond

    2015-06-20

    Complete mechanical preparation of the root canal system is rarely achieved. Therefore, the purpose of this study was to evaluate and compare the root canal shaping efficacy of ProTaper rotary files and standard stainless steel K-files using micro-computed tomography. Sixty extracted upper second premolars were selected and divided into 2 groups of 30 teeth each. Before preparation, all samples were scanned by micro-computed tomography. Thirty teeth were prepared with the ProTaper system and the other 30 with stainless steel files. After preparation, the untouched surface and root canal straightening were evaluated with micro-computed tomography. The percentage of untouched root canal surface was calculated in the coronal, middle, and apical parts of the canal. We also calculated straightening of the canal after root canal preparation. Results from the 2 groups were statistically compared using the Minitab statistical package. ProTaper rotary files left less untouched root canal surface compared with manual preparation in coronal, middle, and apical sector (p<0.001). Similarly, there was a statistically significant difference in root canal straightening after preparation between the techniques (p<0.001). Neither manual nor rotary techniques completely prepared the root canal, and both techniques caused slight straightening of the root canal.

  9. Efficacy of NiTi rotary instruments in removing calcium hydroxide dressing residues from root canal walls

    Directory of Open Access Journals (Sweden)

    Milton Carlos Kuga

    2012-02-01

    Full Text Available The aim of this study was to evaluate the efficacy of three rotary instrument systems (K3, ProTaper and Twisted File in removing calcium hydroxide residues from root canal walls. Thirty-four human mandibular incisors were instrumented with the ProTaper System up to the F2 instrument, irrigated with 2.5% NaOCl followed by 17% EDTA, and filled with a calcium hydroxide intracanal dressing. After 7 days, the calcium hydroxide dressing was removed using the following rotary instruments: G1 - NiTi size 25, 0.06 taper, of the K3 System; G2 - NiTi F2, of the ProTaper System; or G3 - NiTi size 25, 0.06 taper, of the Twisted File System. The teeth were longitudinally grooved on the buccal and lingual root surfaces, split along their long axis, and their apical and cervical canal thirds were evaluated by SEM (×1000. The images were scored and the data were statistically analyzed using the Kruskall Wallis test. None of the instruments removed the calcium hydroxide dressing completely, either in the apical or cervical thirds, and no significant differences were observed among the rotary instruments tested (p > 0.05.

  10. A safety equipment list for rotary mode core sampling systems operation in single shell flammable gas tanks

    International Nuclear Information System (INIS)

    SMALLEY, J.L.

    1999-01-01

    This document identifies all interim safety equipment to be used for rotary mode core sampling of single-shell flammable gas tanks utilizing Rotary Mode Core Sampling systems (RMCS). This document provides the safety equipment for RMCS trucks HO-68K-4600, HO-68K-4647, trucks three and four respectively, and associated equipment. It is not intended to replace or supersede WHC-SD-WM-SEL-023, (Kelly 1991), or WHC-SD-WM-SEL-032, (Corbett 1994), which classifies 80-68K-4344 and HO-68K-4345 respectively. The term ''safety equipment'' refers to safety class (SC) and safety significant (SS) equipment, where equipment refers to structures, systems and components (SSC's). The identification of safety equipment in this document is based on the credited design safety features and analysis contained in the Authorization Basis (AB) for rotary mode core sampling operations in single-shell flammable gas tanks. This is an interim safety classification since the AB is interim. This document will be updated to reflect the final RMCS equipment safety classification designations upon completion of a final AB which will be implemented with the release of the Final Safety Analysis Report (FSAR)

  11. The degradation of lining of rotary furnaces in the production of zinc oxide

    Czech Academy of Sciences Publication Activity Database

    Luptáková, Natália; Pešlová, F.; Anisimov, E.

    2014-01-01

    Roč. 21, č. 3 (2014), s. 116-121 ISSN 1335-0803 Institutional support: RVO:68081723 Keywords : zinc oxide * the production of zinc oxide * zinc slag * refractories * the degradation of rotary furnace linings Subject RIV: JG - Metallurgy http://ojs.mateng.sk/index.php/Mateng/article/view/133/194

  12. QTAIM and Stress Tensor Characterization of Intramolecular Interactions Along Dynamics Trajectories of a Light-Driven Rotary Molecular Motor.

    Science.gov (United States)

    Wang, Lingling; Huan, Guo; Momen, Roya; Azizi, Alireza; Xu, Tianlv; Kirk, Steven R; Filatov, Michael; Jenkins, Samantha

    2017-06-29

    A quantum theory of atoms in molecules (QTAIM) and stress tensor analysis was applied to analyze intramolecular interactions influencing the photoisomerization dynamics of a light-driven rotary molecular motor. For selected nonadiabatic molecular dynamics trajectories characterized by markedly different S 1 state lifetimes, the electron densities were obtained using the ensemble density functional theory method. The analysis revealed that torsional motion of the molecular motor blades from the Franck-Condon point to the S 1 energy minimum and the S 1 /S 0 conical intersection is controlled by two factors: greater numbers of intramolecular bonds before the hop-time and unusually strongly coupled bonds between the atoms of the rotor and the stator blades. This results in the effective stalling of the progress along the torsional path for an extended period of time. This finding suggests a possibility of chemical tuning of the speed of photoisomerization of molecular motors and related molecular switches by reshaping their molecular backbones to decrease or increase the degree of coupling and numbers of intramolecular bond critical points as revealed by the QTAIM/stress tensor analysis of the electron density. Additionally, the stress tensor scalar and vector analysis was found to provide new methods to follow the trajectories, and from this, new insight was gained into the behavior of the S 1 state in the vicinity of the conical intersection.

  13. Film riding seals for rotary machines

    Science.gov (United States)

    Bidkar, Rahul Anil; Sarawate, Neelesh Nandkumar; Wolfe, Christopher Edward; Ruggiero, Eric John; Raj Mohan, Vivek Raja

    2017-03-07

    A seal assembly for a rotary machine is provided. The seal assembly includes multiple sealing device segments disposed circumferentially intermediate to a stationary housing and a rotor. Each of the segments includes a shoe plate with a forward-shoe section and an aft-shoe section having one or more labyrinth teeth therebetween facing the rotor. The sealing device includes a stator interface element having a groove or slot for allowing disposal of a spline seal for preventing segment leakages. The sealing device segment also includes multiple bellow springs or flexures connected to the shoe plate and to the stator interface element. Further, the sealing device segments include a secondary seal integrated with the stator interface element at one end and positioned about the multiple bellow springs or flexures and the shoe plate at the other end.

  14. The Effect of Canal Preparation with Four Different Rotary Systems on Formation of Dentinal Cracks: An In Vitro Evaluation.

    Science.gov (United States)

    Khoshbin, Elham; Donyavi, Zakiyeh; Abbasi Atibeh, Erfan; Roshanaei, Ghodratollah; Amani, Faranak

    2018-01-01

    Endodontic rotary systems may result in dentinal cracks. They may propagate to vertical root fracture that compromises the outcome of endodontic treatment. This study aimed to compare Neolix and Reciproc (single-file systems), Mtwo and ProTaper (conventional rotary systems) in terms of dentinal crack formation in root canal walls. This in vitro study was conducted on 110 extracted human single-rooted teeth. The teeth were randomly divided into four experimental groups ( n =25) for root canal preparation with Neolix, Reciproc, Mtwo and ProTaper systems and two control groups ( n =5). The first control group underwent root canal instrumentation with hand files while the second control group received no preparation and was only irrigated. After instrumentation, root canals were horizontally sectioned at 3, 6 and 9 mm from the apex and inspected under a stereomicroscope under 12× magnification for detection of cracks. The data were analyzed using Chi-square, GEE test and Bonferroni tests ( P ProTaper, Reciproc, Mtwo and Neolix caused cracks in 92%, 80%, 68% and 48% of samples. ProTaper caused significantly more cracks than Neolix and Mtwo ( P 0.05). All rotary systems cause dentinal cracks and it is significantly different in apical, middle and coronal third of the root. Neolix appears to be a suitable alternative to other rotary systems since use of this single-file system saves time and cost and minimizes trauma to dentinal walls.

  15. Surveillance procedure for the rotary drilling operations of a well

    Energy Technology Data Exchange (ETDEWEB)

    Peltier, B; Deshais, R

    1988-06-17

    A surveillance procedure for the rotary drilling operations of a well is proposed. When the drilling pipe is drawn out of the well, or put into the well, pipe elements are taken away or added. At each moment the height of the trepan in the well is measured, together with the traction force of the lifting engine. The device permits to avoid the important damage that can be caused by an error on the drilling pipe's length.

  16. Surveillance procedure for the rotary drilling operations of a well

    Energy Technology Data Exchange (ETDEWEB)

    Peltier, B.; Deshais, R.

    1988-06-17

    A surveillance procedure for the rotary drilling operations of a well is proposed. When the drilling pipe is drawn out of the well, or put into the well, pipe elements are taken away or added. At each moment the height of the trepan in the well is measured, together with the traction force of the lifting engine. The device permits to avoid the important damage that can be caused by an error on the drilling pipe's length.

  17. Experimental results for a novel rotary active magnetic regenerator

    DEFF Research Database (Denmark)

    Engelbrecht, Kurt; Eriksen, Dan; Bahl, Christian

    2012-01-01

    Active magnetic regenerator (AMR) refrigerators represent an alternative to vapor compression technology and have great potential in realizing cooling devices with high efficiency, which are highly desirable for a broad range of applications. The technology relies on the magnetocaloric effect...... in a solid refrigerant rather than the temperature change that occurs when a gas is compressed/expanded. This paper presents the general considerations for the design and construction of a high frequency rotary AMR device. Experimental results are presented at various cooling powers for a range of operating...

  18. Pendulation control system and method for rotary boom cranes

    Science.gov (United States)

    Robinett, III, Rush D.; Groom, Kenneth N.; Feddema, John T.; Parker, Gordon G.

    2002-01-01

    A command shaping control system and method for rotary boom cranes provides a way to reduce payload pendulation caused by real-time input signals, from either operator command or automated crane maneuvers. The method can take input commands and can apply a command shaping filter to reduce contributors to payload pendulation due to rotation, elevation, and hoisting movements in order to control crane response and reduce tangential and radial payload pendulation. A filter can be applied to a pendulation excitation frequency to reduce residual radial pendulation and tangential pendulation amplitudes.

  19. Rotary Ultrasonic Machining of Poly-Crystalline Cubic Boron Nitride

    Directory of Open Access Journals (Sweden)

    Kuruc Marcel

    2014-12-01

    Full Text Available Poly-crystalline cubic boron nitride (PCBN is one of the hardest material. Generally, so hard materials could not be machined by conventional machining methods. Therefore, for this purpose, advanced machining methods have been designed. Rotary ultrasonic machining (RUM is included among them. RUM is based on abrasive removing mechanism of ultrasonic vibrating diamond particles, which are bonded on active part of rotating tool. It is suitable especially for machining hard and brittle materials (such as glass and ceramics. This contribution investigates this advanced machining method during machining of PCBN.

  20. Evidence for Reduced Fatigue Resistance of Contemporary Rotary Instruments Exposed to Body Temperature.

    Science.gov (United States)

    de Vasconcelos, Rafaela Andrade; Murphy, Sarah; Carvalho, Claudio Antonio Talge; Govindjee, Rajiv G; Govindjee, Sanjay; Peters, Ove A

    2016-05-01

    The purpose of this study was to evaluate the effect of 2 different temperatures (20°C and 37°C) on the cyclic fatigue life of rotary instruments and correlate the results with martensitic transformation temperatures. Contemporary nickel-titanium rotary instruments (n = 20 each and tip size #25, including Hyflex CM [Coltene, Cuyahoga Falls, OH], TRUShape [Dentsply Tulsa Dental Specialties, Tulsa, OK], Vortex Blue [Dentsply Tulsa Dental Specialties], and ProTaper Universal [Dentsply Tulsa Dental Specialties]) were tested for cyclic fatigue at room temperature (20°C ± 1°C) and at body temperature (37°C ± 1°C). Instruments were rotated until fracture occurred in a simulated canal with an angle curvature of about 60° and a radius curvature of 3 mm; the center of the curvature was 4.5 mm from the instrument tip. The number of cycles to fracture was measured. Phase transformation temperatures for 2 instruments of each brand were analyzed by differential scanning calorimetry. Data were analyzed using the t test and 1-way analysis of variance with the significance level set at 0.05. For the tested size and at 20°C, Hyflex CM showed the highest resistance to fracture; no significant difference was found between TRUShape and Vortex Blue, whereas ProTaper Universal showed the lowest resistance to fracture. At 37°C, resistance to fatigue fracture was significantly reduced, up to 85%, for the tested instruments (P rotary instruments tested. Copyright © 2016 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  1. Testing Of The Dual Rotary Filter System

    International Nuclear Information System (INIS)

    Herman, D.; Fowley, M.; Stefanko, D.

    2011-01-01

    The Savannah River National Laboratory (SRNL) installed and tested two hydraulically connected SpinTek rotary microfilter (RMF) units to determine the behavior of a multiple filter system. Both units were successfully controlled by a control scheme written in DELTA-V architecture by Savannah River Remediation (SRR) Process Control Engineering personnel. The control system was tuned to provide satisfactory response to changing conditions during the operation of the multi-filter system. Stability was maintained through the startup and shutdown of one of the filter units while the second was still in operation. The installation configuration originally proposed by the Small Colum Ion Exchange (SCIX) project of independent filter and motor mountings may be susceptible to vibration. Significant stiffening of the filter and motor mounts was required to minimize the vibration. Alignment of the motor to the filter was a challenge in this test configuration. The deployment configuration must be easy to manipulate and allow for fine adjustment. An analysis of the vibration signature of the test system identified critical speeds. Whether it corresponds to the resonance frequency of a rotor radial vibration mode that was excited by rotor unbalance is uncertain based upon the measurements. A relative motion series should be completed on the filter with the final shaft configuration to determine if the resonances exist in the final filter design. The instrumentation selected for deployment, including the concentrate discharge control valve and flow meters, performed well. Automation of the valve control integrated well with the control scheme and when used in concert with the other control variables, allowed automated control of the dual RMF system. The one area of concern with the instrumentation was the condition resulting when the filtrate flow meter operated with less than three gpm. This low flow was at the lower range of performance for the flow meter. This should not be

  2. TESTING OF THE DUAL ROTARY FILTER SYSTEM

    Energy Technology Data Exchange (ETDEWEB)

    Herman, D.; Fowley, M.; Stefanko, D.

    2011-08-29

    The Savannah River National Laboratory (SRNL) installed and tested two hydraulically connected SpinTek rotary microfilter (RMF) units to determine the behavior of a multiple filter system. Both units were successfully controlled by a control scheme written in DELTA-V architecture by Savannah River Remediation (SRR) Process Control Engineering personnel. The control system was tuned to provide satisfactory response to changing conditions during the operation of the multi-filter system. Stability was maintained through the startup and shutdown of one of the filter units while the second was still in operation. The installation configuration originally proposed by the Small Colum Ion Exchange (SCIX) project of independent filter and motor mountings may be susceptible to vibration. Significant stiffening of the filter and motor mounts was required to minimize the vibration. Alignment of the motor to the filter was a challenge in this test configuration. The deployment configuration must be easy to manipulate and allow for fine adjustment. An analysis of the vibration signature of the test system identified critical speeds. Whether it corresponds to the resonance frequency of a rotor radial vibration mode that was excited by rotor unbalance is uncertain based upon the measurements. A relative motion series should be completed on the filter with the final shaft configuration to determine if the resonances exist in the final filter design. The instrumentation selected for deployment, including the concentrate discharge control valve and flow meters, performed well. Automation of the valve control integrated well with the control scheme and when used in concert with the other control variables, allowed automated control of the dual RMF system. The one area of concern with the instrumentation was the condition resulting when the filtrate flow meter operated with less than three gpm. This low flow was at the lower range of performance for the flow meter. This should not be

  3. Residual magnetic field in rotary machines; Campo magnetico residual en maquinas rotatorias

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez V, Esteban A; Apanco R, Marcelino [Instituto de Investigaciones Electricas, Cuernavaca, Morelos (Mexico)

    2007-07-01

    The residual magnetism is a phenomenon in which the magnetic dipoles of a substance are oriented in a certain degree. On the other hand, when internal forces exist capable of aligning elementary magnetic dipoles of a material, a permanent magnet is obtained. Just as in a conductor or in a material, in the elements of a rotary electrical machine magnetic fields can be induced that produce a residual magnetism or magnetization. In the rotary electrical machines, the magnetization phenomenon causes serious problems, such as the generation of induced currents that propitiate the mechanical wear in bearings, collars, trunnions and inclusive in the shaft, by effects known as pitting, frosting and spark tracks, as well as erroneous readings in vibration and temperature sensors, that in some cases can cause the shut down of the machine. In this article are presented the general concepts on the residual magnetism in rotary electrical machines, the causes that originate it and the problems that arises, as well as the demagnetization of the components that have residual magnetic field. The results obtained by the area of Electrical Equipment of the Instituto de Investigaciones Electricas are revised, during the execution of activities related to the measurement and elimination of the residual magnetic field in rotary electrical machines. [Spanish] El magnetismo residual es un fenomeno en el que los dipolos magneticos de una sustancia se encuentran orientados en un grado determinado. Por otro lado, cuando existen fuerzas internas capaces de alinear los dipolos magneticos elementales de un material, se tiene un iman permanente. Al igual que en un conductor o un material, en los elementos de una maquina electrica rotatoria se pueden inducir campos magneticos que producen un magnetismo residual o magnetizacion. En las maquinas electricas rotatorias, el fenomeno de magnetizacion causa graves problemas, como la generacion de corrientes inducidas que propician el desgaste mecanico

  4. Torque-coupled thermodynamic model for FoF1 -ATPase

    Science.gov (United States)

    Ai, Guangkuo; Liu, Pengfei; Ge, Hao

    2017-05-01

    FoF1 -ATPase is a motor protein complex that utilizes transmembrane ion flow to drive the synthesis of adenosine triphosphate (ATP) from adenosine diphosphate (ADP) and phosphate (Pi). While many theoretical models have been proposed to account for its rotary activity, most of them focus on the Fo or F1 portions separately rather than the complex as a whole. Here, we propose a simple but new torque-coupled thermodynamic model of FoF1 -ATPase. Solving this model at steady state, we find that the monotonic variation of each portion's efficiency becomes much more robust over a wide range of parameters when the Fo and F1 portions are coupled together, as compared to cases when they are considered separately. Furthermore, the coupled model predicts the dependence of each portion's kinetic behavior on the parameters of the other. Specifically, the power and efficiency of the F1 portion are quite sensitive to the proton gradient across the membrane, while those of the Fo portion as well as the related Michaelis constants for proton concentrations respond insensitively to concentration changes in the reactants of ATP synthesis. The physiological proton gradient across the membrane in the Fo portion is also shown to be optimal for the Michaelis constants of ADP and phosphate in the F1 portion during ATP synthesis. Together, our coupled model is able to predict key dynamic and thermodynamic features of the FoF1 -ATPase in vivo semiquantitatively, and suggests that such coupling approach could be further applied to other biophysical systems.

  5. Analysis of thermally coupled chemical looping combustion-based power plants with carbon capture

    KAUST Repository

    Iloeje, Chukwunwike

    2015-04-01

    © 2015 Elsevier Ltd. A number of CO2 capture-enabled power generation technologies have been proposed to address the negative environmental impact of CO2 emission. One important barrier to adopting these technologies is the associated energy penalty. Chemical-looping Combustion (CLC) is an oxy-combustion technology that can significantly lower this penalty. It utilizes an oxygen carrier to transfer oxygen from air/oxidizing stream in an oxidation reactor to the fuel in a reduction reactor. Conventional CLC reactor designs employ two separate reactors, with metal/metal oxide particles circulating pneumatically in-between. One of the key limitations of these designs is the entropy generation due to reactor temperature difference, which lowers the cycle efficiency. Zhao et al. (Zhao et al., 2014; Zhao and Ghoniem, 2014) proposed a new CLC rotary reactor design, which overcomes this limitation. This reactor consists of a single rotating wheel with micro-channels designed to maintain thermal equilibrium between the fuel and air sides. This study uses three thermodynamic models of increasing fidelity to demonstrate that the internal thermal coupling in the rotary CLC reactor creates the potential for improved cycle efficiency. A theoretical availability model and an ideal thermodynamic cycle model are used to define the efficiency limits of CLC systems, illustrate the impact of reactor thermal coupling and discuss relevant criteria. An Aspen Plus® model of a regenerative CLC cycle is then used to show that this thermal coupling raises the cycle efficiency by up to 2% points. A parametric study shows that efficiency varies inversely with pressure, with a maximum of 51% at 3bar, 1000C and 60% at 4bar, 1400C. The efficiency increases with CO2 fraction at high pressure ratios but exhibits a slight inverse dependence at low pressure ratios. The parametric study shows that for low purge steam demand, steam generation improves exhaust heat recovery and increases efficiency

  6. TESTING OF A FULL-SCALE ROTARY MICROFILTER FOR THE ENHANCED PROCESS FOR RADIONUCLIDES REMOVAL

    Energy Technology Data Exchange (ETDEWEB)

    Herman, D; David Stefanko, D; Michael Poirier, M; Samuel Fink, S

    2009-01-01

    Savannah River National Laboratory (SRNL) researchers are investigating and developing a rotary microfilter for solid-liquid separation applications in the Department of Energy (DOE) complex. One application involves use in the Enhanced Processes for Radionuclide Removal (EPRR) at the Savannah River Site (SRS). To assess this application, the authors performed rotary filter testing with a full-scale, 25-disk unit manufactured by SpinTek Filtration with 0.5 micron filter media manufactured by Pall Corporation. The filter includes proprietary enhancements by SRNL. The most recent enhancement is replacement of the filter's main shaft seal with a John Crane Type 28LD gas-cooled seal. The feed material was SRS Tank 8F simulated sludge blended with monosodium titanate (MST). Testing examined total insoluble solids concentrations of 0.06 wt % (126 hours of testing) and 5 wt % (82 hours of testing). The following are conclusions from this testing.

  7. Mechanical and Metallurgical Properties of Various Nickel-Titanium Rotary Instruments

    Directory of Open Access Journals (Sweden)

    Kyu-Sang Shim

    2017-01-01

    Full Text Available The aim of this study was to investigate the effect of thermomechanical treatment on mechanical and metallurgical properties of nickel-titanium (NiTi rotary instruments. Eight kinds of NiTi rotary instruments with sizes of ISO #25 were selected: ProFile, K3, and One Shape for the conventional alloy; ProTaper NEXT, Reciproc, and WaveOne for the M-wire alloy; HyFlex CM for the controlled memory- (CM- wire; and TF for the R-phase alloy. Torsional fracture and cyclic fatigue fracture tests were performed. Products underwent a differential scanning calorimetry (DSC analysis. The CM-wire and R-phase groups had the lowest elastic modulus, followed by the M-wire group. The maximum torque of the M-wire instrument was comparable to that of a conventional instrument, while those of the CM-wire and R-phase instruments were lower. The angular displacement at failure (ADF for the CM-wire and R-phase instruments was higher than that of conventional instruments, and ADF of the M-wire instruments was lower. The cyclic fatigue resistance of the thermomechanically treated NiTi instruments was higher. DSC plots revealed that NiTi instruments made with the conventional alloy were primarily composed of austenite at room temperature; stable martensite and R-phase were found in thermomechanically treated instruments.

  8. Machining of Some Difficult-to-Cut Materials with Rotary Cutting Tools

    OpenAIRE

    Stjernstoft, Tero

    2004-01-01

    Automobile and aero industries have an increasing interestin materials with improved mechanical properties. However, manyof these new materials are classified as difficult-to-cut withconventional tools. It is obvious that tools, cutting processesand cutting models has to be devel-oped parallel to materialsscience. In this thesis rotary cutting tools are tested as analternative toexpensive diamond or cubic bore nitridetools. Metal matrix composites mostly consist of a light metalalloy (such as...

  9. Simulation investigation of flow field inside the rotary engine : during intake and compression stroke

    Energy Technology Data Exchange (ETDEWEB)

    Poojitganont, T.; Berg, H.P.; Izweik, H.T. [Brandenburg Univ. of Technology Cottbus, Cottbus (Germany)

    2009-07-01

    As a result of continuously increasing oil prices, automotive industries are looking for alternative power sources for their automobiles. An excellent solution is the hybrid system. However due to the additional weight of its batteries, this causes the total weight of the car to increase. This higher battery weight can be compensated by reducing the weight of the engine. A rotary engine, such as the Wankel rotary engine, has a more attractive power to weight ratio than the normal reciprocating engine. The rotary engine can be treated and evaluated with respect to performance characteristics as a displacement type, four-stroke internal combustion engine, one-cycle similar to the reciprocating engine. For any combustion engine to reach the maximum power output, the mixture formation inside the engine should be considered. The flow phenomenon inside the engine is a key parameter which involves the mixture formation mechanism. This paper investigated the spray characteristic from the injector and the flow phenomena inside the combustion chamber. Its behaviours were studied using computational fluid dynamics simulation. The simulation setup was described in detail, with reference to meshes; initial condition; and boundary condition. Verification of the calculation was also presented. A comparison of the temperature during compression stroke from the analytical calculation and the adiabetic system simulation were also illustrated. Simulation results showed that the speed of the engine provides a proportional effect on the magnitude of air velocity inside the engine, whereas the circulation region can be expanded by increasing the intake pressure during the intake stroke. 9 refs., 1 tab., 13 figs.

  10. Apical extrusion of bacteria when using reciprocating single-file and rotary multifile instrumentation systems.

    Science.gov (United States)

    Tinoco, J M; De-Deus, G; Tinoco, E M B; Saavedra, F; Fidel, R A S; Sassone, L M

    2014-06-01

    To evaluate ex vivo, apical bacterial extrusion associated with two reciprocating single-file systems (WaveOne and Reciproc) compared with a conventional multifile rotary system (BioRace). Forty-five human single-rooted mandibular incisors were used. Endodontic access cavities were prepared, and root canals were contaminated with an Enterococcus faecalis suspension. Following incubation at 37 °C for thirty days, the contaminated teeth were divided into three groups of 15 specimens each (G1 - Reciproc, G2 - WaveOne and G3 - BioRace). Positive and negative controls consisted of 5 infected teeth and 3 uninfected incisors that were instrumented with one of the tested NiTi systems, respectively. Bacteria extruded from the apical foramen during instrumentation were collected into vials containing 0.9% NaCl. The microbiological samples were taken from the vials and incubated in brain heart agar medium for 24 h. The resulting bacterial titre, in colony-forming units (CFU) per mL, was determined, and these data were analysed by Wilcoxon matched-pairs signed rank test and Kruskal-Wallis H-test. The level of significance was set at α = 0.05. No significant difference was found in the number of CFU between the two reciprocating systems (P = 0.41). The conventional multifile rotary system group was associated with significantly higher CFU than both of the two reciprocating groups (P = 0.01). All instrumentation systems extruded bacteria beyond the foramen. However, both reciprocating single-file systems extruded fewer bacteria apically than the conventional multifile rotary system. © 2013 International Endodontic Journal. Published by John Wiley & Sons Ltd.

  11. A comparison of nickel-titanium rotary instruments manufactured using different methods and cross-sectional areas: ability to resist cyclic fatigue.

    Science.gov (United States)

    Oh, So-Ram; Chang, Seok-Woo; Lee, Yoon; Gu, Yu; Son, Won-Jun; Lee, Woocheol; Baek, Seung-Ho; Bae, Kwang-Shik; Choi, Gi-Woon; Lim, Sang-Min; Kum, Kee-Yeon

    2010-04-01

    This study examined the effect of the manufacturing methods (ground, electropolished, and twisted) and the cross-sectional area (CSA) of nickel-titanium (NiTi) rotary instruments on their cyclic fatigue resistance. A total of 80 NiTi rotary instruments (ISO 25/.06 taper) from 4 brands (K3, ProFile, RaCe, and TF) were rotated in a simulated root canal with pecking motion until fracture. The number of cycles to failure (NCF) was calculated. The CSA at 3 mm from the tip of new instruments of each brand was calculated. The correlation between the CSA and NCF was evaluated. All fractured surfaces were analyzed using a scanning electron microscope to determine the fracture mode. The TF instruments were the most resistant to fatigue failure. The resistance to cyclic failure increased with decreasing CSA. All fractured surfaces showed the coexistence of ductile and brittle properties. The CSA had a significant effect on the fatigue resistance of NiTi rotary instruments. Copyright 2010 Mosby, Inc. All rights reserved.

  12. Application of Adaptive Starling-Like Controller to Total Artificial Heart Using Dual Rotary Blood Pumps.

    Science.gov (United States)

    Ng, Boon C; Smith, Peter A; Nestler, Frank; Timms, Daniel; Cohn, William E; Lim, Einly

    2017-03-01

    The successful clinical applicability of rotary left ventricular assist devices (LVADs) has led to research interest in devising a total artificial heart (TAH) using two rotary blood pumps (RBPs). The major challenge when using two separately controlled LVADs for TAH support is the difficulty in maintaining the balance between pulmonary and systemic blood flows. In this study, a starling-like controller (SLC) hybridized with an adaptive mechanism was developed for a dual rotary LVAD TAH. The incorporation of the adaptive mechanism was intended not only to minimize the risk of pulmonary congestion and atrial suction but also to match cardiac demand. A comparative assessment was performed between the proposed adaptive starling-like controller (A-SLC) and a conventional SLC as well as a constant speed controller. The performance of all controllers was evaluated by subjecting them to three simulated scenarios [rest, exercise, head up tilt (HUT)] using a mock circulation loop. The overall results showed that A-SLC was superior in matching pump flow to cardiac demand without causing hemodynamic instabilities. In contrast, improper flow regulation by the SLC resulted in pulmonary congestion during exercise. From resting supine to HUT, overpumping of the RBPs at fixed speed (FS) caused atrial suction, whereas implementation of SLC resulted in insufficient flow. The comparative study signified the potential of the proposed A-SLC for future TAH implementation particularly among outpatients, who are susceptible to variety of clinical scenarios.

  13. Rotary MR Damper for Launch/Landing Load Isolation and Resistive Crew Exercise for Exploration Spaceflight Missions

    Data.gov (United States)

    National Aeronautics and Space Administration — Develop a rotary MR (magneto rheologic) Damper to integrate into exploration spacecraft crew seats to be used as an exercise device and launch/landing load isolation...

  14. Effectiveness of supplementary irrigant agitation with the Finisher GF Brush on the debridement of oval root canals instrumented with the Gentlefile or nickel titanium rotary instruments.

    Science.gov (United States)

    Neelakantan, P; Khan, K; Li, K Y; Shetty, H; Xi, W

    2018-07-01

    To examine the efficacy of a novel supplementary irrigant agitating brush (Finisher GF Brush, MedicNRG, Kibbutz Afikim, Israel) on the debridement of root canals prepared with a novel stainless steel rotary instrumentation system (Gentlefile; MedicNRG), or nickel titanium rotary instruments in oval root canals. Mandibular premolars (n = 72) were selected and divided randomly into three experimental groups (n = 24) after microCT scanning: group 1, canal preparation to rotary NiTi size 20, .04 taper (R20); group 2, rotary NiTi to size 25, .04 taper (R25) and group 3, Gentlefile size 23, .04 taper (GF). Specimens were subdivided into two subgroups: subgroup A, syringe-and-needle irrigation (SNI); subgroup B, Finisher GF Brush (GB). Ten untreated canals served as controls. Specimens were processed for histological evaluation, and the remaining pulp tissue (RPT) was measured. Data were analysed using Mann-Whitney and Kruskal-Wallis tests (P = 0.05). All experimental groups had significantly less RPT than the control (P  0.05). When instrumented with R20, there was no significant difference between SNI and GF (P rotary NiTi. Root canal debridement did not significantly differ between the instruments when syringe irrigation was used. © 2018 International Endodontic Journal. Published by John Wiley & Sons Ltd.

  15. Production of activated charcoal beads or green moldnings useful in stationary or fluidized bed uses rotary stirrer(s) for mixing carbonaceous powder with binder

    DEFF Research Database (Denmark)

    2000-01-01

    In the production of activated charcoal beads or green moldings by mixing carbonaceous powder with a binder, mixing is carried out in a stirred vessel with rotary stirrer(s).......In the production of activated charcoal beads or green moldings by mixing carbonaceous powder with a binder, mixing is carried out in a stirred vessel with rotary stirrer(s)....

  16. Research on the Cross Section Precision of High-strength Steel Tube with Rectangular Section in Rotary Draw Bending

    Science.gov (United States)

    Yang, Hongliang; Zhao, Hao; Xing, Zhongwen

    2017-11-01

    For the demand of energy conservation and security improvement, high-strength steel (HSS) is increasingly being used to produce safety related automotive components. However, cross-section distortion occurs easily in bending of HSS tube with rectangular section (RS), affecting the forming precision. HSS BR1500HS tube by rotary draw bending is taken as the study object and a description method of cross-section distortion is proposed in this paper. The influence on cross-section precision of geometric parameters including cross-section position, thickness of tube, bend radius etc. are studied by experiment. Besides, simulation of the rotary draw bending of HSS tube with rectangular section by ABAQUS are carried out and compared to the experiment. The results by simulation agree well with the experiment and show that the cross-section is approximately trapezoidal after distortion; the maximum of distortion exists at 45 ∼ 60° of the bending direction; and the absolute and relative distortion values increase with the decreasing of tube thickness or bending radius. Therefore, the results can provide a reference for the design of geometric parameters of HSS tube with rectangular section in rotary draw bending.

  17. A safety equipment list for rotary mode core sampling systems operation in single shell flammable gas tanks; TOPICAL

    International Nuclear Information System (INIS)

    SMALLEY, J.L.

    1999-01-01

    This document identifies all interim safety equipment to be used for rotary mode core sampling of single-shell flammable gas tanks utilizing Rotary Mode Core Sampling systems (RMCS). This document provides the safety equipment for RMCS trucks HO-68K-4600, HO-68K-4647, trucks three and four respectively, and associated equipment. It is not intended to replace or supersede WHC-SD-WM-SEL-023, (Kelly 1991), or WHC-SD-WM-SEL-032, (Corbett 1994), which classifies 80-68K-4344 and HO-68K-4345 respectively. The term ''safety equipment'' refers to safety class (SC) and safety significant (SS) equipment, where equipment refers to structures, systems and components (SSC's). The identification of safety equipment in this document is based on the credited design safety features and analysis contained in the Authorization Basis (AB) for rotary mode core sampling operations in single-shell flammable gas tanks. This is an interim safety classification since the AB is interim. This document will be updated to reflect the final RMCS equipment safety classification designations upon completion of a final AB which will be implemented with the release of the Final Safety Analysis Report (FSAR)

  18. Stereomicroscopic evaluation of defects caused by torsional fatigue in used hand and rotary nickel-titanium instruments.

    Science.gov (United States)

    Asthana, Geeta; Kapadwala, Marsrat I; Parmar, Girish J

    2016-01-01

    The aim of this study was to evaluate defects caused by torsional fatigue in used hand and rotary nickel-titanium (Ni-Ti) instruments by stereomicroscopic examination. One hundred five greater taper Ni-Ti instruments were used including Protaper universal hand (Dentsply Maillefer, Ballaigues, Switzerland), Protaper universal rotary (Dentsply Maillefer, Ballaigues, Switzerland), and Revo-S rotary (MicroMega, Besançon, France) files. Files were used on lower anterior teeth. After every use, the files were observed with both naked eyes and stereomicroscope at 20× magnification (Olympus, Shinjuku, Tokyo, Japan) to evaluate defects caused by torsional fatigue. Scoring was assigned to each file according to the degree of damage. The results were statistically analyzed using the Mann-Whitney U test and the Kruskal-Wallis test. A greater number of defects were seen under the stereomicroscope than on examining with naked eyes. However, the difference in methods of evaluation was not statistically significant. Revo-S files showed minimum defects, while Protaper universal hand showed maximum defects. The intergroup comparison of defects showed that the bend in Protaper universal hand instruments was statistically significant. Visible defects in Ni-Ti files due to torsional fatigue were seen by naked eyes as well as by stereomicroscope. This study emphasizes that all the files should be observed before and after every instrument cycle to minimize the risk of separation.

  19. In Vitro Comparison of Apically Extruded Debris during Root Canal Preparation of Mandibular Premolars with Manual and Rotary Instruments.

    Science.gov (United States)

    Soi, Sonal; Yadav, Suman; Sharma, Sumeet; Sharma, Mohit

    2015-01-01

    Background and aims. During root canal preparation, debris extruded beyond the apical foramen may result in periapical inflammation and postoperative pain. To date no root canal preparation method has been developed that extrudes no periapical debris. The purpose of this study was to identify a system leading to minimal extrusion of debris from the apical foramen. The study was conducted to comparatively evaluate the amount of apical extrusion of debris during root canal preparation using hand ProTaper and GT rotary and RaCe rotary instruments using crown-down technique. Materials and methods. Ninety freshly extracted human single-rooted mandibular premolars were equally assigned to three groups (n=30). The root canals were instrumented using hand ProTaper, GT rotary and RaCe rotary systems. Debris and irrigant extruded from the apical foramen were collected into vials. The mean weight of the remaining debris was calculated for each group and subjected to statistical analysis. Results. ANOVA was used to compare the mean dry weights of the debris extruded in the three groups, followedby post hoc Tukey tests for multiple comparisons the between groups. Highly significant differences were found in the amount of debris extruded among all the groups (PProTaper group exhibited the highest mean debris weight (0.8293±0.05433 mg) and the RaCe system exhibited the lowest mean debris weight (0.1280±0.01606 mg). Conclusion. All the systems tested resulted in apical extrusion of debris. However, the hand ProTaper files extruded a significantly higher amount of debris than GT and RaCe systems.

  20. Evaluation of conventional, protaper hand and protaper rotary instrumentation system for apical extrusion of debris, irrigants and bacteria- An in vitro randomized trial.

    Science.gov (United States)

    Kalra, Pinky; Rao, Arathi; Suman, Ethel; Shenoy, Ramya; Suprabha, Baranya-Shrikrishna

    2017-02-01

    Endodontic instrumentation carries the risk of over extrusion of debris and bacteria. The technique used and the type of instrumentation influences this risk. The purpose of this study was to evaluate and compare the K-file, ProTaper hand and ProTaper rotary instrumentation systems for the amount of apically extruded debris, irrigant solution and intracanal bacteria. Experimental single blinded randomized type of in vitro study with sample of 30 single rooted teeth. Endodontic access cavities were prepared and the root canals were filled with the suspension of E. faecalis . Myers and Montogomery Model was used to collect apically extruded debris and irrigant. Canals were prepared using K files, Hand protapers and Protaper rotary files. Non Parametric test like Kruskal-Wallis and Mann-Whitney U test were applied to determine the significant differences among the group. Tests revealed statistically significant difference between the amount of debris and number of bacteria extruded by the ProTaper hand and the K-files. No statistically significant difference was observed between the amounts of irrigant extruded by the ProTaper hand and the K-file system. Statistically significant differences were observed between the amounts of bacteria and irrigant extruded by the ProTaper rotary and the Protaper hand. No statistically significant difference was observed between the amounts of debris extruded by the ProTaper hand and the K-file system. Amount of apical extrusion of irrigant solution, bacteria and debris are significantly greater with K File instruments and least with Protaper rotary instruments. Key words: Protaper, rotary, periapical extrusion.

  1. Comparative Study of Three Rotary Instruments for root canal Preparation using Computed Tomography

    International Nuclear Information System (INIS)

    Mohamed, A.M.E.

    2015-01-01

    Cleaning and shaping the root canal is a key to success in root canal treatment. This includes the removal of organic substrate from the root canal system by chemo mechanical methods, and the shaping of the root canal system into a continuously tapered preparation. This should be done while maintaining the original path of the root canal. Although instruments for root canal preparation have been progressively developed and optimized, a complete mechanical debridement of the root canal system is rarely achievable. One of the main reasons is the geometrical dis symmetry between the root canal and preparation instruments. Rotary instruments regardless of their type and form produce a preparation with a round outline if they are used in a simple linear filing motion, which in most of the cases do not coincide with the outline of the root canal. Root canal preparation in narrow, curved canals is a challenge even for experienced endodontists. Shaping of curved canals became more effective after the introduction of nickel-titanium (Ni-Ti) endodontic instruments. Despite the advantages of Ni-Ti rotary instruments, intra canal fracture is the most common procedural accident that occurs with these instruments during clinical use. It is a common experience between clinicians that Ni-Ti rotary instruments may undergo unexpected fracture without any visible warning, such as any previous permanent defect or deformation. Pro Taper Ni-Ti instruments were introduced with a unique design of variable taper within one instrument and continuously changing helical angles. Pro Taper rotary instruments are claimed to generate lower torque values during their use because of their modified nonradial landed cross-section that increases the cutting efficiency and reduces contact areas. On the other hand, the variable taper within one instrument is believed to reduce the ‘taper lock’ effect (torsional failure) in comparison with similarly tapered instruments. Nevertheless, Pro Taper

  2. Evaluation of cyclic flexural fatigue of M-wire nickel-titanium rotary instruments.

    Science.gov (United States)

    Al-Hadlaq, Solaiman M S; Aljarbou, Fahad A; AlThumairy, Riyadh I

    2010-02-01

    This study was conducted to investigate cyclic flexural fatigue resistance of GT series X rotary files made from the newly developed M-wire nickel-titanium alloy compared with GT and Profile nickel-titanium files made from a conventional nickel-titanium alloy. Fifteen files, size 30/0.04, of each type were used to evaluate the cyclic flexural fatigue resistance. A simple device was specifically constructed to measure the time each file type required to fail under cyclic flexural fatigue testing. The results of this experiment indicated that the GT series X files had superior cyclic flexural fatigue resistance than the other 2 file types made from a conventional nickel-titanium alloy (P = .004). On the other hand, the difference between the Profile and the GT files was not statistically significant. The findings of this study suggest that size 30/0.04 nickel-titanium rotary files made from the newly developed M-wire alloy have better cyclic flexural fatigue resistance than files of similar design and size made from the conventional nickel-titanium alloy. Copyright 2010 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  3. Cyclic Fatigue of Different Nickel-Titanium Rotary Instruments: A Comparative Study

    OpenAIRE

    Testarelli, L.; Grande, N.M; Plotino, G; Lendini, M; Pongione, G; Paolis, G. De; Rizzo, F; Milana, V; Gambarini, G

    2009-01-01

    Since the introduction of nickel-titanium alloy to endodontics, there have been many changes in instrument design, but no significant improvements in the raw material properties, or enhancements in the manufacturing process. Recently, a new method to produce nickel-titanium rotary (NTR) instruments has been developed, in an attempt to obtain instruments that are more flexible and resistant to fatigue. NTR instruments produced using the process of twisting (TF, SybronEndo, Orange, CA) were com...

  4. CFD SIMULATION FOR DEMILITARIZATION OF RDX IN A ROTARY KILN BY THERMAL DECOMPOSITION

    Directory of Open Access Journals (Sweden)

    SI H. LEE

    2017-06-01

    Full Text Available Demilitarization requires the recovery and disposal of obsolete ammunition and explosives. Since open burning/detonation of hazardous waste has caused serious environmental and safety problems, thermal decomposition has emerged as one of the most feasible methods. RDX is widely used as a military explosive due to its high melting temperature and detonation power. In this work, the feasible conditions under which explosives can be safely incinerated have been investigated via a rotary kiln simulation. To solve this problem, phase change along with the reactions of RDX has been incisively analyzed. A global reaction mechanism consisting of condensed phase and gas phase reactions are used in Computational Fluid Dynamics simulation. User Defined Functions in FLUENT is utilized in this study to inculcate the reactions and phase change into the simulation. The results divulge the effect of temperature and the varying amounts of gas produced in the rotary kiln during the thermal decomposition of RDX. The result leads to the prospect of demilitarizing waste explosives to avoid the possibility of detonation.

  5. The degradation of lining of rotary furnaces in the production of zinc oxide

    Directory of Open Access Journals (Sweden)

    Natália Luptáková

    2014-06-01

    Full Text Available This paper is closely connected with the complex problem of degradation relating to the refractories of rotary furnace linings in the production of zinc oxide. Zinc oxide can be produced by variety of ways, but the most common method of production which is used in Europe is indirect, i.e. pyrolytic combustion of zinc. This method is also called "French process" of manufacturing ZnO. But this mentioned method of preparation leads to the creation of the enormous amount of zinc slag including chemical complexes of elements Fe, Zn and Al. The mechanism of degradation of the lining leads to slag rests and it is closely connected with the mutual interaction of the aggressive agents with the components of the lining. This process creates a new undesired surface layer which increased the overall thickness of zinc slag. Stuck slag has the influence on rapid degradation of the linings and moreover it also decreases the production quality of ZnO. Analysis results introduced in this paper are significant information for minimizing of degradation of rotary furnaces.  

  6. Tribologic analysis and technical innovation for rotary molding press

    International Nuclear Information System (INIS)

    Luo Wei; Bai Yumeng; Dai Xingjian

    2012-01-01

    The rotary molding press R53C-Y is the key facility in the compression molding working procedure of the nu clear fuel pellets. Its main compression assembly called the upper compression roller frame has been worn seriously during the production. At first, the mechanical model of the upper compression roller assembly was established for analysis and calculation physical strength. Then the wear causations of the upper compression roller frame were analyzed, and the existent problems of central lubrication system were discussed. Finally, Oil-air central lubrication system was designed considering the characteristic of nuclear fuel pellets production. (authors)

  7. Effect of Instrumentation Length and Instrumentation Systems: Hand Versus Rotary Files on Apical Crack Formation - An In vitro Study.

    Science.gov (United States)

    Devale, Madhuri R; Mahesh, M C; Bhandary, Shreetha

    2017-01-01

    Stresses generated during root canal instrumentation have been reported to cause apical cracks. The smaller, less pronounced defects like cracks can later propagate into vertical root fracture, when the tooth is subjected to repeated stresses from endodontic or restorative procedures. This study evaluated occurrence of apical cracks with stainless steel hand files, rotary NiTi RaCe and K3 files at two different instrumentation lengths. In the present in vitro study, 60 mandibular premolars were mounted in resin blocks with simulated periodontal ligament. Apical 3 mm of the root surfaces were exposed and stained using India ink. Preoperative images of root apices were obtained at 100x using stereomicroscope. The teeth were divided into six groups of 10 each. First two groups were instrumented with stainless steel files, next two groups with rotary NiTi RaCe files and the last two groups with rotary NiTi K3 files. The instrumentation was carried out till the apical foramen (Working Length-WL) and 1 mm short of the apical foramen (WL-1) with each file system. After root canal instrumentation, postoperative images of root apices were obtained. Preoperative and postoperative images were compared and the occurrence of cracks was recorded. Descriptive statistical analysis and Chi-square tests were used to analyze the results. Apical root cracks were seen in 30%, 35% and 20% of teeth instrumented with K-files, RaCe files and K3 files respectively. There was no statistical significance among three instrumentation systems in the formation of apical cracks (p=0.563). Apical cracks were seen in 40% and 20% of teeth instrumented with K-files; 60% and 10% of teeth with RaCe files and 40% and 0% of teeth with K3 files at WL and WL-1 respectively. For groups instrumented with hand files there was no statistical significance in number of cracks at WL and WL-1 (p=0.628). But for teeth instrumented with RaCe files and K3 files significantly more number of cracks were seen at WL than

  8. Improvements for rotary viscous dampers used in spacecraft deployment mechanisms

    Science.gov (United States)

    Stewart, Alphonso; Powers, Charles; Lyons, Ron

    1998-01-01

    During component level thermal-vacuum deployment testing of eight rotary viscous dampers for the Tropical Rainfall Measuring Mission (TRMM) satellite, all the dampers failed to provide damping during a region of the deployment. Radiographic examination showed that air in the damping fluid caused the undamped motion when the dampers were operated in a vacuum environment. Improvements in the procedure used to fill the dampers with damping fluid, the installation of a Viton vacuum seal in the damper cover, and improved screening techniques eliminated the problem.

  9. Introduction to curved rotary tomographic apparatus 'TOMOREX'

    International Nuclear Information System (INIS)

    Kubota, Kazuo; Shinojima, Masayasu; Kohirasawa, Hideo; Tokui, Mitsuru

    1980-01-01

    In recent years, panorama X-ray photographic method is widely used for the X-ray diagnosis of teeth, jawbones and faces. One type based on the principle of tomography is curved surface rotary tomographic method utilizing fine-gap X-ray beam. With the synchronous rotation of an X-ray tube and a photographic film around a face, describing a U-shaped tomographic plane along a dental arch, an upper or lower jawbone is photographed. In the ''TOMOREX'' belonging to this type, is different tomographic planes are available, so that by selecting any position in advance, the part can be photographed. Furthermore, patients can be subjected to examination as laid on a stretcher. The mechanism and equipment, and the photographic method for eye sockets, cheekbones, upper jaw cavities and stereoscopic images are described. (J.P.N.)

  10. Dissolution of intact UO2 pellet in batch and rotary dissolver conditions

    International Nuclear Information System (INIS)

    Jayendra Kumar Gelatar; Bijendra Kumar; Sampath, M.; Shekhar Kumar; Kamachi Mudali, U.; Natarajan, R.

    2015-01-01

    Comparative dissolution of intact un-irradiated UO 2 pellet of PHWR fuel dimensions was performed in batch and dynamic rotary dissolver conditions in aqueous nitric acid solutions at elevated temperatures. The extent of dissolution was estimated by determining the uranium concentration of the resulting aqueous solution. It was observed that rate of dissolution was much faster in dynamic conditions as compared to static batch conditions. (author)

  11. Optically powered and interrogated rotary position sensor for aircraft engine control applications

    Science.gov (United States)

    Spillman, W. B.; Crowne, D. H.; Woodward, D. W.

    A throttle level angle (TLA) sensing system is described that utilizes a capacitance based rotary position transducer that is powered and interrogated via light from a single multimode optical fiber. The system incorporates a unique GaAs device that serves as both a power converter and optical data transmitter. Design considerations are discussed, and the fabrication and performance of the sensor system are detailed.

  12. Chemical reaction engineering aspects of a rotary reactor for carbothermal synthesis of SiC

    NARCIS (Netherlands)

    van Dijen, F.K.; Metselaar, R.

    1989-01-01

    Heat transfer in a rotary reactor is described for a reactor consisting of a graphite tube with graphite heating elements, and operating at temperatures between 1773 and 2273 K. Under those conditions heat transfer is very good due to radiation and the high thermal conductivity of graphite. An

  13. Application of unsteady airfoil theory to rotary wings

    Science.gov (United States)

    Kaza, K. R. V.; Kvaternik, R. G.

    1981-01-01

    A clarification is presented on recent work concerning the application of unsteady airfoil theory to rotary wings. The application of this theory may be seen as consisting of four steps: (1) the selection of an appropriate unsteady airfoil theory; (2) the resolution of that velocity which is the resultant of aerodynamic and dynamic velocities at a point on the elastic axis into radial, tangential and perpendicular components, and the angular velocity of a blade section about the deformed axis; (3) the expression of lift and pitching moments in terms of the three components; and (4) the derivation of explicit expressions for the components in terms of flight velocity, induced flow, rotor rotational speed, blade motion variables, etc.

  14. Lead scrap processing in rotary furnaces: a review

    Energy Technology Data Exchange (ETDEWEB)

    Rousseau, M

    1987-01-01

    Formerly, the lead scrap had been processed mainly in reverberatory and shaft furnaces or, even, in rotary furnaces (R.F.). The direct smelting of battery scrap entrains an expensive pollution control and high operating costs because of slag recirculation, coke consumption, losses in slag and matte. Nowadays, mechanized battery wrecking plants allow selective separation of casings and separators from metallic Pb (grids, poles, solders) as well as lead in non-metallic form (PbSO/sub 4/, PbO, PbO/sub 2/, contaminated with some Sb) frequently called paste. Because of their high performance and flexibility in metallurgical processing (melting, reducing, oxidizing and selective pouring) the R.F. supersedes the reverberatory furnace worldwide.

  15. PRODUCTION OF ROTARY ENGINES’ PARTS FROM ALUMINUM ALLOYS USING LOST FOAM CASTING PROCESS

    Directory of Open Access Journals (Sweden)

    E. I. Marukovich

    2018-01-01

    Full Text Available The production technology of casting details for rotary engine from the aluminum alloy АК12М2 is developed. The bulk density of expanded polystyrene to ensure the best quality of the surface of castings has been experimentally established. The lost foam casting shop was organized in the experimental department of the Institute.

  16. Investigations of Effect of Rotary EDM Electrode on Machining Performance of Al6061 Alloy

    Science.gov (United States)

    Robinson Smart, D. S.; Jenish Smart, Joses; Periasamy, C.; Ratna Kumar, P. S. Samuel

    2018-04-01

    Electric Discharge Machining is an essential process which is being used for machining desired shape using electrical discharges which creates sparks. There will be electrodes subjected to electric voltage and which are separated by a dielectric liquid. Removing of material will be due to the continuous and rapid current discharges between two electrodes.. The spark is very carefully controlled and localized so that it only affects the surface of the material. Usually in order to prevent the defects which are arising due to the conventional machining, the Electric Discharge Machining (EDM) machining is preferred. Also intricate and complicated shapes can be machined effectively by use of Electric Discharge Machining (EDM). The EDM process usually does not affect the heat treat below the surface. This research work focus on the design and fabrication of rotary EDM tool for machining Al6061alloy and investigation of effect of rotary tool on surface finish, material removal rate and tool wear rate. Also the effect of machining parameters of EDM such as pulse on & off time, current on material Removal Rate (MRR), Surface Roughness (SR) and Electrode wear rate (EWR) have studied. Al6061 alloy can be used for marine and offshore applications by reinforcing some other elements. The investigations have revealed that MRR (material removal rate), surface roughness (Ra) have been improved with the reduction in the tool wear rate (TWR) when the tool is rotating instead of stationary. It was clear that as rotary speed of the tool is increasing the material removal rate is increasing with the reduction of surface finish and tool wear rate.

  17. System design specification for rotary mode core sample trucks No. 2, 3, and 4 programmable logic controller

    International Nuclear Information System (INIS)

    Dowell, J.L.; Akers, J.C.

    1995-01-01

    The system this document describes controls several functions of the Core Sample Truck(s) used to obtain nuclear waste samples from various underground storage tanks at Hanford. The system will monitor the sampling process and provide alarms and other feedback to insure the sampling process is performed within the prescribed operating envelope. The intended audience for this document is anyone associated with rotary or push mode core sampling. This document describes the Alarm and Control logic installed on Rotary Mode Core Sample Trucks (RMCST) number-sign 2, 3, and 4. It is intended to define the particular requirements of the RMCST alarm and control operation (not defined elsewhere) sufficiently for detailed design to implement on a Programmable Logic Controller (PLC)

  18. Application of non-destructive impedance-based monitoring technique for cyclic fatigue evaluation of endodontic nickel-titanium rotary instruments.

    Science.gov (United States)

    Chang, Yau-Zen; Liu, Mou-Chuan; Pai, Che-An; Lin, Chun-Li; Yen, Kuang-I

    2011-06-01

    This study investigates the application of non-destructive testing based on the impedance theory in the cyclic fatigue evaluation of endodontic Ni-Ti rotary instruments. Fifty Ni-Ti ProTaper instruments were divided into five groups (n=10 in Groups A to E). Groups A to D were subjected to cyclic fatigue within an artificial canal (Group E was the control group). The mean value of the total life limit (TLL), defined as the instrument being rotated until fracture occurred was found to be 104 s in Group A. Each rotary instrument in Groups B, C and D were rotated until the tested instruments reached 80% (84 s), 60% (62 s) and 40% (42 s) of the TLL. After fatigue testing, each rotary instrument was mounted onto a custom-developed non-destructive testing device to give the tip of the instrument a progressive sideways bend in four mutually perpendicular directions to measure the corresponding impedance value (including the resistance and the reactance). The results indicated that the impedance value showed the same trend as the resistance, implying that the impedance was primarily affected by the resistance. The impedance value for the instruments in the 80% and 60% TLL groups increased by about 6 mΩ (about 7.5%) more than that of the instruments in the intact and 40% TLL groups. The SEM analysis result showed that crack striations were only found at the tip of the thread on the cracked surface of the instrument, consistent with the impedance measurements that found the impedance value of the cracked surface to be significantly different from those in other surfaces. These findings indicate that the impedance value may represent an effective parameter for evaluating the micro-structural status of Ni-Ti rotary instruments subjected to fatigue loading. Copyright © 2010 IPEM. Published by Elsevier Ltd. All rights reserved.

  19. A finite wake theory for two-dimensional rotary wing unsteady aerodynamics

    OpenAIRE

    Couch, Mark A.

    1993-01-01

    Approved for public release; distribution is unlimited. The unsteady aerodynamic forces and moments of an oscillating airfoil for the fixed wing case were determined by Theodorsen along with the development of a lift deficiency function. Loewy subsequently developed an analogous lift deficiency function for the rotary wing case in which there are an infinite number of layers of shed vorticity, or wakes, below the reference airfoil. With the advent of computer panel codes that calculate the...

  20. NASA Subsonic Rotary Wing Project-Multidisciplinary Analysis and Technology Development: Overview

    Science.gov (United States)

    Yamauchi, Gloria K.

    2009-01-01

    This slide presentation reviews the objectives of the Multidisciplinary Analysis and Technology Development (MDATD) in the Subsonic Rotary Wing project. The objectives are to integrate technologies and analyses to enable advanced rotorcraft and provide a roadmap to guide Level 1 and 2 research. The MDATD objectives will be met by conducting assessments of advanced technology benefits, developing new or enhanced design tools, and integrating Level 2 discipline technologies to develop and enable system-level analyses and demonstrations.

  1. Rotary drum for a centrifugal separator

    International Nuclear Information System (INIS)

    Fukai, Tamotsu.

    1970-01-01

    Herein provided is a rotary drum designed to prevent strength reduction and eccentric weight redistribution at the joints between the drum body and the end cups therefore when materials having divergent specific gravities, strengths and Young's Modulus are employed as the construction materials for the drum body and end cups. The drum body is fabricated by combining glass, carbon boron or similar high strength fibers with a thermosetting hardenable resin. This composite material is then molded into the finished cylindrical product the ends of which are bent slightly inward to receive a rigid, high-strength, ring-shaped end fitting to be integrally joined thereto during the molding operation. Each ring is further adapted to retain an end cap by a procedure which entails lowering the temperature of the end cap and applying heat to the ring, thus joining both members tightly together by employing the differences in thermal expansion of each. (Owens, K. J.)

  2. An in vitro assessment of the physical properties of novel Hyflex nickel-titanium rotary instruments.

    Science.gov (United States)

    Peters, O A; Gluskin, A K; Weiss, R A; Han, J T

    2012-11-01

    To determine several properties including torsional and fatigue limits, as well as torque during canal preparation, of Hyflex, a rotary instrument manufactured from so-called controlled memory nickel-titanium alloy. The instruments were tested in vitro using a special torque bench that permits both stationary torque tests according to ISO3630-1 and fatigue limit determination, as well as measurement of torque (in Ncm) and apical force (in N) during canal preparation. Fatigue limit (in numbers of cycles to failure) was determined in a 90°, 5 mm radius block-and-rod assembly. Simulated canals in plastic blocks were prepared using both a manufacturer-recommended single-length technique as well as a generic crown-down approach. anova with Bonferroni post hoc procedures was used for statistical analysis. Torque at failure ranged from 0.47 to 1.38 Ncm, with significant differences between instrument sizes (P instruments size 20, .04 taper and size 25, .08 taper, respectively. Torque during canal preparation was significantly higher for small instruments used in the single-length technique but lower for the size 40, .04 taper, compared to a crown-down approach. No instrument fractured; 82% of the instruments used were plastically deformed; however, only 37% of these remained deformed after a sterilization cycle. Hyflex rotary instruments are bendable and flexible and have similar torsional resistance compared to instruments made of conventional NiTi. Fatigue resistance is much higher, and torque during preparation is less, compared to other rotary instruments tested previously under similar conditions. © 2012 International Endodontic Journal.

  3. MEMS based shock pulse detection sensor for improved rotary Stirling cooler end of life prediction

    Science.gov (United States)

    Hübner, M.; Münzberg, M.

    2018-05-01

    The widespread use of rotary Stirling coolers in high performance thermal imagers used for critical 24/7 surveillance tasks justifies any effort to significantly enhance the reliability and predictable uptime of those coolers. Typically the lifetime of the whole imaging device is limited due to continuous wear and finally failure of the rotary compressor of the Stirling cooler, especially due to failure of the comprised bearings. MTTF based lifetime predictions, even based on refined MTTF models taking operational scenario dependent scaling factors into account, still lack in precision to forecast accurately the end of life (EOL) of individual coolers. Consequently preventive maintenance of individual coolers to avoid failures of the main sensor in critical operational scenarios are very costly or even useless. We have developed an integrated test method based on `Micro Electromechanical Systems', so called MEMS sensors, which significantly improves the cooler EOL prediction. The recently commercially available MEMS acceleration sensors have mechanical resonance frequencies up to 50 kHz. They are able to detect solid borne shock pulses in the cooler structure, originating from e.g. metal on metal impacts driven by periodical forces acting on moving inner parts of the rotary compressor within wear dependent slack and play. The impact driven transient shock pulse analyses uses only the high frequency signal <10kHz and differs therefore from the commonly used broadband low frequencies vibrational analysis of reciprocating machines. It offers a direct indicator of the individual state of wear. The predictive cooler lifetime model based on the shock pulse analysis is presented and results are discussed.

  4. In Vitro Comparison of Apically Extruded Debris during Root Canal Preparation of Mandibular Premolars with Manual and Rotary Instruments

    Directory of Open Access Journals (Sweden)

    Sonal Soi

    2015-09-01

    Full Text Available Background and aims. During root canal preparation, debris extruded beyond the apical foramen may result in periapical inflammation and postoperative pain. To date no root canal preparation method has been developed that extrudes no peri-apical debris. The purpose of this study was to identify a system leading to minimal extrusion of debris from the apical fo-ramen. The study was conducted to comparatively evaluate the amount of apical extrusion of debris during root canal prepa-ration using hand ProTaper and GT rotary and RaCe rotary instruments using crown-down technique. Materials and methods. Ninety freshly extracted human single-rooted mandibular premolars were equally assigned to three groups (n=30. The root canals were instrumented using hand ProTaper, GT rotary and RaCe rotary systems. Debris and irrigant extruded from the apical foramen were collected into vials. The mean weight of the remaining debris was calcu-lated for each group and subjected to statistical analysis. Results. ANOVA was used to compare the mean dry weights of the debris extruded in the three groups, followedby post hoc Tukey tests for multiple comparisons the between groups. Highly significant differences were found in the amount of debris extruded among all the groups (P<0.001. The ProTaper group exhibited the highest mean debris weight (0.8293±0.05433 mg and the RaCe system exhibited the lowest mean debris weight (0.1280±0.01606 mg. Conclusion. All the systems tested resulted in apical extrusion of debris. However, the hand ProTaper files extruded a sig-nificantly higher amount of debris than GT and RaCe systems.

  5. In Vitro Comparison of Apically Extruded Debris during Root Canal Preparation of Mandibular Premolars with Manual and Rotary Instruments

    Science.gov (United States)

    Soi, Sonal; Yadav, Suman; Sharma, Sumeet; Sharma, Mohit

    2015-01-01

    Background and aims. During root canal preparation, debris extruded beyond the apical foramen may result in periapical inflammation and postoperative pain. To date no root canal preparation method has been developed that extrudes no periapical debris. The purpose of this study was to identify a system leading to minimal extrusion of debris from the apical foramen. The study was conducted to comparatively evaluate the amount of apical extrusion of debris during root canal preparation using hand ProTaper and GT rotary and RaCe rotary instruments using crown-down technique. Materials and methods. Ninety freshly extracted human single-rooted mandibular premolars were equally assigned to three groups (n=30). The root canals were instrumented using hand ProTaper, GT rotary and RaCe rotary systems. Debris and irrigant extruded from the apical foramen were collected into vials. The mean weight of the remaining debris was calculated for each group and subjected to statistical analysis. Results. ANOVA was used to compare the mean dry weights of the debris extruded in the three groups, followedby post hoc Tukey tests for multiple comparisons the between groups. Highly significant differences were found in the amount of debris extruded among all the groups (P<0.001). The ProTaper group exhibited the highest mean debris weight (0.8293±0.05433 mg) and the RaCe system exhibited the lowest mean debris weight (0.1280±0.01606 mg). Conclusion. All the systems tested resulted in apical extrusion of debris. However, the hand ProTaper files extruded a significantly higher amount of debris than GT and RaCe systems. PMID:26697144

  6. The Application of Unmanned Rotary-Wing Aircraft in Tactical Logistics in Support of Joint Operations

    Science.gov (United States)

    2013-12-13

    Reconnaissance Squadrons with a fixed-wing unmanned aircraft troop or company, and is in the market for an autonomous cargo unmanned rotary-wing...Warwick, Graham. “Sky Patrol.” Aviation Week & Space Technology 174, no. 32 (September 3, 2012): 55. Military & Government Collection, EBSCOhost

  7. The ability of different nickel-titanium rotary instruments to induce dentinal damage during canal preparation

    NARCIS (Netherlands)

    Bier, C.A.S.; Shemesh, H.; Tanomaru-Filho, M.; Wesselink, P.R.; Wu, M.K.

    2009-01-01

    The purpose of this study was to compare the incidence of dentinal defects (fractures and craze lines) after canal preparation with different nickel-titanium rotary files. Two hundred sixty mandibular premolars were selected. Forty teeth were left unprepared (n = 40). The other teeth were prepared

  8. Dynamic Analysis of the Temperature and the Concentration Profiles of an Industrial Rotary Kiln Used in Clinker Production

    Directory of Open Access Journals (Sweden)

    DIULIA C.Q. RODRIGUES

    Full Text Available ABSTRACT Cement is one of the most used building materials in the world. The process of cement production involves numerous and complex reactions that occur under different temperatures. Thus, there is great interest in the optimization of cement manufacturing. Clinker production is one of the main steps of cement production and it occurs inside the kiln. In this paper, the dry process of clinker production is analysed in a rotary kiln that operates in counter flow. The main phenomena involved in clinker production is as follows: free residual water evaporation of raw material, decomposition of magnesium carbonate, decarbonation, formation of C3A and C4AF, formation of dicalcium silicate, and formation of tricalcium silicate. The main objective of this study was to propose a mathematical model that realistically describes the temperature profile and the concentration of clinker components in a real rotary kiln. In addition, the influence of different speeds of inlet gas and solids in the system was analysed. The mathematical model is composed of partial differential equations. The model was implemented in Mathcad (available at CCA/UFES and solved using industrial input data. The proposal model is satisfactory to describe the temperature and concentration profiles of a real rotary kiln.

  9. Dynamic Analysis of the Temperature and the Concentration Profiles of an Industrial Rotary Kiln Used in Clinker Production.

    Science.gov (United States)

    Rodrigues, Diulia C Q; Soares, Atílio P; Costa, Esly F; Costa, Andréa O S

    2017-01-01

    Cement is one of the most used building materials in the world. The process of cement production involves numerous and complex reactions that occur under different temperatures. Thus, there is great interest in the optimization of cement manufacturing. Clinker production is one of the main steps of cement production and it occurs inside the kiln. In this paper, the dry process of clinker production is analysed in a rotary kiln that operates in counter flow. The main phenomena involved in clinker production is as follows: free residual water evaporation of raw material, decomposition of magnesium carbonate, decarbonation, formation of C3A and C4AF, formation of dicalcium silicate, and formation of tricalcium silicate. The main objective of this study was to propose a mathematical model that realistically describes the temperature profile and the concentration of clinker components in a real rotary kiln. In addition, the influence of different speeds of inlet gas and solids in the system was analysed. The mathematical model is composed of partial differential equations. The model was implemented in Mathcad (available at CCA/UFES) and solved using industrial input data. The proposal model is satisfactory to describe the temperature and concentration profiles of a real rotary kiln.

  10. Cyclic Fatigue Resistance of Novel Rotary Files Manufactured from Different Thermal Treated Nickel-Titanium Wires in Artificial Canals.

    Science.gov (United States)

    Karataşlıoglu, E; Aydın, U; Yıldırım, C

    2018-02-01

    The aim of this in vitro study was to compare the static cyclic fatigue resistance of thermal treated rotary files with a conventional nickel-titanium (NiTi) rotary file. Four groups of 60 rotary files with similar file dimensions, geometries, and motion were selected. Groups were set as HyFlex Group [controlled memory wire (CM-Wire)], ProfileVortex Group (M-Wire), Twisted File Group (R-Phase Wire), and OneShape Group (conventional NiTi wire)] and tested using a custom-made static cyclic fatigue testing apparatus. The fracture time and fragment length of the each file was also recorded. Statistical analysis was performed using one-way analysis of variance and Tukey's test at the 95% confidence level (P = 0.05). The HyFlex group had a significantly higher mean cyclic fatigue resistance than the other three groups (P Wire alloy represented the best performance in cyclic fatigue resistance, and NiTi alloy in R-Phase had the second highest fatigue resistance. CM and R-Phase manufacturing technology processed to the conventional NiTi alloy enhance the cyclic fatigue resistance of files that have similar design and size. M-wire alloy did not show any superiority in cyclic fatigue resistance when compared with conventional NiTi wire.

  11. Thermal neutron flux measurements in the rotary specimen rack of the IPR-R1 TRIGA reactor

    Energy Technology Data Exchange (ETDEWEB)

    Souza, Rose Mary G. do Prado; Rodrigues, Rogério R.; Souza, Luiz Claudio A., E-mail: souzarm@cdtn.br, E-mail: rrr@cdtn.br, E-mail: lcas@cdtn.br [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)

    2017-07-01

    The thermal neutron flux in the rotary specimen rack of the IPR-R1 TRIGA reactor at the Nuclear Technology Development Center (CDTN), Belo Horizonte, Brazil, has been measured by the neutron activation method, using bare and cadmium covered gold foils. Those foils were irradiated in the rotary specimen rack with the reactor at 100 kW. The reactor core configuration has 63 fuel elements, composed of 59 original aluminum-clad elements and 4 stainless steel-clad fuel elements. The gamma activities of the foils were measured using Ge spectrometer. The perturbations of the thermal neutron flux caused by the introduction of an absorbing foil into the medium were considered in order to obtain accurate determination of the flux. The thermal neutron flux obtained was 7.4 x 10{sup 11} n.cm{sup -2}.s{sup -1}. (author)

  12. MR-fluid yield surface determination in disc-type MR rotary brakes

    International Nuclear Information System (INIS)

    Farjoud, Alireza; Vahdati, Nader; Fah, Yap Fook

    2008-01-01

    Magneto-rheological (MR) fluids are currently attracting a great deal of attention because of their unique rheological behavior. Many devices have been designed using MR fluids, and of potential interest here are disc-type MR rotary brakes. The plug flow region in MR devices is defined as the region where the fluid is not flowing. The plug flow region plays an important role in design and analysis of MR devices. In MR dampers, the damping coefficient is a function of the plug thickness. In MR valves, the plug thickness is used to control the flow rate through, and the pressure drop across, the MR valve. A MR clutch is performing at the highest efficiency when the entire MR gap is the plug region. For an MR rotary brake, the highest restraining torque is obtained when the entire gap is the plug region as far as there are no wall slip effects. In this paper, using the Bercovier and Engelman constitutive model, the MR fluid flow in disc-type MR brakes is modeled to determine the plug flow region. The resulting system of equations is solved numerically. It is shown that the existence of a plug flow region in the brake will affect the control torque ratio. Better estimation of the plug flow region results in better estimation of the viscous torque

  13. Experience with Aerosol Generation During Rotary Mode Core Sampling in the Hanford Single Shell Waste Tanks

    International Nuclear Information System (INIS)

    SCHOFIELD, J.S.

    1999-01-01

    This document provides data on aerosol concentrations in tank head spaces, total mass of aerosols in the tank head space and mass of aerosols sent to the exhauster during Rotary Mode Core Sampling from November 1994 through April 1999

  14. Effect of Instrumentation Length and Instrumentation Systems: Hand Versus Rotary Files on Apical Crack Formation – An In vitro Study

    Science.gov (United States)

    Mahesh, MC; Bhandary, Shreetha

    2017-01-01

    Introduction Stresses generated during root canal instrumentation have been reported to cause apical cracks. The smaller, less pronounced defects like cracks can later propagate into vertical root fracture, when the tooth is subjected to repeated stresses from endodontic or restorative procedures. Aim This study evaluated occurrence of apical cracks with stainless steel hand files, rotary NiTi RaCe and K3 files at two different instrumentation lengths. Materials and Methods In the present in vitro study, 60 mandibular premolars were mounted in resin blocks with simulated periodontal ligament. Apical 3 mm of the root surfaces were exposed and stained using India ink. Preoperative images of root apices were obtained at 100x using stereomicroscope. The teeth were divided into six groups of 10 each. First two groups were instrumented with stainless steel files, next two groups with rotary NiTi RaCe files and the last two groups with rotary NiTi K3 files. The instrumentation was carried out till the apical foramen (Working Length-WL) and 1 mm short of the apical foramen (WL-1) with each file system. After root canal instrumentation, postoperative images of root apices were obtained. Preoperative and postoperative images were compared and the occurrence of cracks was recorded. Descriptive statistical analysis and Chi-square tests were used to analyze the results. Results Apical root cracks were seen in 30%, 35% and 20% of teeth instrumented with K-files, RaCe files and K3 files respectively. There was no statistical significance among three instrumentation systems in the formation of apical cracks (p=0.563). Apical cracks were seen in 40% and 20% of teeth instrumented with K-files; 60% and 10% of teeth with RaCe files and 40% and 0% of teeth with K3 files at WL and WL-1 respectively. For groups instrumented with hand files there was no statistical significance in number of cracks at WL and WL-1 (p=0.628). But for teeth instrumented with RaCe files and K3 files

  15. Modification of Cassava Starch Using Lactic Acid Hydrolysis in The Rotary-UV Dryer to Improve Physichocemical Properties

    Directory of Open Access Journals (Sweden)

    Sumardiono Siswo

    2018-01-01

    Full Text Available Food security should be supported in an effort to utilize local products into import substitution products. Cassava starch has the potential to be developed into semi-finished products in the form of flour or starch which does not contain gluten but can inflate large baking process, potentially as a substitute for wheat flour-the main ingredient for making bread. The characteristic of the starch is influenced by the type of starch composition and structure. Natural starch has physicochemical properties i.e. a long time cooking and pasta formed hard. These constraints allow us to modify cassava starch by a combination of lactic acid hydrolysis and drying with rotary UV system. Modified cassava starch is expected to be used as a substitute for wheat flour. The aim of the research which is a combination of lactic acid hydrolysis and drying using a rotary UV system is to examine the optimum operating conditions in the drying process of starch hydrolysis with parameter the physicochemical and rheological properties of modified cassava starch. The initial process study is to hydrolyze cassava starch using lactic acid. Furthermore, hydrolyzed cassava starch is then dried using UV light in the rotary dryers system. There are a variety of changing variables, i.e. time of irradiation cassava starch-lactic acid hydrolysis products in the rotary UV light and air drying temperature. The research results show that modified starch has a better characteristic than the natural starch. From the analysis, the best point of swelling power, solubility and baking expansion is consequently 15.62 g/g; 24.19 %; 2.21 ml/gr. The FTIR result shows that there is no significant difference of the chemical structure because the starch modification only change the physical characteristics. From the SEM analysis, we can know that the size of the starch’s granule changes between the natural starch and the modified starch..

  16. Piezoelectric Versus Conventional Rotary Techniques for Impacted Third Molar Extraction: A Meta-analysis of Randomized Controlled Trials.

    Science.gov (United States)

    Jiang, Qian; Qiu, Yating; Yang, Chi; Yang, Jingyun; Chen, Minjie; Zhang, Zhiyuan

    2015-10-01

    Impacted third molars are frequently encountered in clinical work. Surgical removal of impacted third molars is often required to prevent clinical symptoms. Traditional rotary cutting instruments are potentially injurious, and piezosurgery, as a new osteotomy technique, has been introduced in oral and maxillofacial surgery. No consistent conclusion has been reached regarding whether this new technique is associated with fewer or less severe postoperative sequelae after third molar extraction.The aim of this study was to compare piezosurgery with rotary osteotomy techniques, with regard to surgery time and the severity of postoperative sequelae, including pain, swelling, and trismus.We conducted a systematic literature search in the Cochrane Library, PubMed, Embase, and Google Scholar.The eligibility criteria of this study included the following: the patients were clearly diagnosed as having impacted mandibular third molars; the patients underwent piezosurgery osteotomy, and in the control group rotary osteotomy techniques, for removing impacted third molars; the outcomes of interest include surgery time, trismus, swelling or pain; the studies are randomized controlled trials.We used random-effects models to calculate the difference in the outcomes, and the corresponding 95% confidence interval. We calculated the weighted mean difference if the trials used the same measurement, and a standardized mean difference if otherwise.A total of seven studies met the eligibility criteria and were included in our analysis. Compared with rotary osteotomy, patients undergoing piezosurgery experienced longer surgery time (mean difference 4.13 minutes, 95% confidence interval 2.75-5.52, P piezosurgery groups.The number of included randomized controlled trials and the sample size of each trial were relatively small, double blinding was not possible, and cost analysis was unavailable due to a lack of data.Our meta-analysis indicates that although patients undergoing piezosurgery

  17. Energy and exergy performance analysis of a marine rotary desiccant air-conditioning system based on orthogonal experiment

    International Nuclear Information System (INIS)

    Zhu, Jun; Chen, Wu

    2014-01-01

    A novel marine rotary desiccant A/C (air-conditioning) system was developed and studied to improve energy utilization efficiency of ship A/C. The orthogonal experiment was first carried out to investigate the influence of various parameters of the marine rotary desiccant A/C system. During the orthogonal experiment the analysis of variance was used to exclude interference from the secondary influencing factor on system performance. The significant influencing factors of system were studied in great detail using the first and second laws of thermodynamics to find optimal setting parameters for best system performance. It is suggested from the analysis results that as regeneration temperature increases, the COP th (thermal coefficient of performance) and exergy efficiency of system (η e ) decreases by 46.9% and 38.8% respectively. They decrease in proportion to the increase of the temperature. η e reaches its maximum value of about 23.5% when the inlet humidity ratio of process air is 22 g/kg. Besides, the exergy loss of system concentrates on the regeneration air heater, the desiccant wheel and the regeneration air leaving the desiccant wheel, which account for 68.4%–81% of the total exergy loss. It can be concluded that applying the marine rotary desiccant A/C in high-temperature and high-humidity marine environment is advantageous. - Highlights: • Significant influencing factors of the system are found by the analysis of variance. • The change trends of the COP th and the η e are nearly proportional with the regeneration temperature. • The η e reaches its maximum value (about 23.5%) when the inlet humidity ratio of process air is 22 g/kg. • The contribution rate of the dry-bulb temperature of fresh air is up to 73.91% for the COP th . • Applying the marine rotary desiccant A/C in high-temperature and high-humidity marine environment is advantageous

  18. Cyclic fatigue resistance of newly manufactured rotary nickel titanium instruments used in different rotational directions.

    Science.gov (United States)

    Gambarini, Gianlucca; Gergi, Richard; Grande, Nicola Maria; Osta, Nada; Plotino, Gianluca; Testarelli, Luca

    2013-12-01

    The aim of this study was to investigate whether cyclic fatigue resistance is increased for nickel titanium instruments manufactured with improved heating processes in clockwise or counterclockwise continuous rotation. The instruments compared were produced either using the R-phase heat treatment (K3XF; SybronEndo, Orange, CA, USA) or the M-wire alloy (ProFile Vortex; DENTSPLY Tulsa Dental Specialties, Tulsa, OK, USA). Tests were performed with a specific cyclic fatigue device that evaluated cycles to failure of rotary instruments in curved artificial canals. Results indicated no significant difference in resistance to cyclic fatigue when rotary nickel titanium instruments are used in clockwise or counterclockwise continuous rotation. In both directions of rotation, size 04-25 K3XF showed a significant increase (P < 0.05) in the mean number of cycles to failure when compared with size 04-25 ProFile Vortex. © 2012 The Authors. Australian Endodontic Journal © 2012 Australian Society of Endodontology.

  19. A quantitative analysis of rotary, ultrasonic and manual techniques to treat proximally flattened root canals

    Directory of Open Access Journals (Sweden)

    Fabiana Soares Grecca

    2007-04-01

    Full Text Available OBJECTIVE: The efficiency of rotary, manual and ultrasonic root canal instrumentation techniques was investigated in proximally flattened root canals. MATERIAL AND METHODS: Forty human mandibular left and right central incisors, lateral incisors and premolars were used. The pulp tissue was removed and the root canals were filled with red die. Teeth were instrumented using three techniques: (i K3 and ProTaper rotary systems; (ii ultrasonic crown-down technique; and (iii progressive manual technique. Roots were bisected longitudinally in a buccolingual direction. The instrumented canal walls were digitally captured and the images obtained were analyzed using the Sigma Scan software. Canal walls were evaluated for total canal wall area versus non-instrumented area on which dye remained. RESULTS: No statistically significant difference was found between the instrumentation techniques studied (p<0.05. CONCLUSION: The findings of this study showed that no instrumentation technique was 100% efficient to remove the dye.

  20. Impact Dynamics of a Percussive System Based on Rotary-Percussive Ultrasonic Drill

    Directory of Open Access Journals (Sweden)

    Yinchao Wang

    2017-01-01

    Full Text Available This paper presents an impact dynamic analysis of a percussive system based on rotary-percussive ultrasonic drill (RPUD. The RPUD employs vibrations on two sides of one single piezoelectric stack to achieve rotary-percussive motion, which improves drilling efficiency. The RPUD’s percussive system is composed of a percussive horn, a free mass, and a drill tool. The percussive horn enlarges longitudinal vibration from piezoelectric stack and delivers the vibration to the drill tool through the free mass, which forms the percussive motion. Based on the theory of conservation of momentum and Newton’s impact law, collision process of the percussive system under no-load condition is analyzed to establish the collision model between the percussive horn, the free mass, and the drill tool. The collision model shows that free mass transfers high-frequency small-amplitude vibration of percussive horn into low-frequency large-amplitude vibration of drill tool through impact. As an important parameter of free mass, the greater the weight of the free mass, the higher the kinetic energy obtained by drill tool after collision. High-speed camera system and drilling experiments are employed to validate the inference results of collision model by using a prototype of the RPUD.

  1. Agglomerate formation and growth mechanisms during melt agglomeration in a rotary processor.

    Science.gov (United States)

    Vilhelmsen, Thomas; Schaefer, Torben

    2005-11-04

    The purpose of this study was to investigate the effect of the binder particle size and the binder addition method on the mechanisms of agglomerate formation and growth during melt agglomeration in a laboratory scale rotary processor. Lactose monohydrate was agglomerated with molten polyethylene glycol (PEG) 3000 by adding the PEG either as solid particles from the size fraction 0-250, 250-500, or 500-750 microm or as droplets with a median size of 25, 48, or 69 microm. It was found that the PEG particle size, the PEG droplet size, and the massing time significantly influenced the agglomerate size and size distribution. Agglomerate formation and growth were found to occur primarily by distribution and coalescence for the PEG size fraction 0-250 microm and mainly by the immersion mechanism for the PEG size fractions 250-500 and 500-750 microm. When the PEG was sprayed upon the lactose, the mechanism of agglomerate formation was supposed to be a mixture of immersion and distribution, and the agglomerate growth was found to occur by coalescence regardless of the PEG mean droplet size. Compared to high shear mixers and conventional fluid bed granulators, the mechanisms of agglomerate formation and growth in the rotary processor resembled mostly those seen in the fluid bed granulator.

  2. Rotary Valve & Beamline Highlights for Fiscal Year 2017

    Energy Technology Data Exchange (ETDEWEB)

    Fitsos, P [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2017-09-21

    This Fiscal Year (FY) work was divided between continued testing and characterization work of the Rotary Valve (RV) and mechanical engineering support for the beamline hardware stands. This configuration is more like the final setup with the accelerator firing deuterons down the evacuated beamline toward the RV for interaction with the deuterium and neutron production. The beamline cells were part of an experiment to reduce the impact that RV gas would have on the beamline vacuum. This work will be reported separately from this report. Previous testing had been with the beamline at atmospheric pressure and now the goal was to get test results of the RV with it connected to a beamline that’s running at some level of vacuum.

  3. Computed tomography evaluation of rotary systems on the root canal transportation and centering ability

    Directory of Open Access Journals (Sweden)

    André PAGLIOSA

    2015-01-01

    Full Text Available Abstract : The endodontic preparation of curved and narrow root canals is challenging, with a tendency for the prepared canal to deviate away from its natural axis. The aim of this study was to evaluate, by cone-beam computed tomography, the transportation and centering ability of curved mesiobuccal canals in maxillary molars after biomechanical preparation with different nickel-titanium (NiTi rotary systems. Forty teeth with angles of curvature ranging from 20° to 40° and radii between 5.0 mm and 10.0 mm were selected and assigned into four groups (n = 10, according to the biomechanical preparative system used: Hero 642 (HR, Liberator (LB, ProTaper (PT, and Twisted File (TF. The specimens were inserted into an acrylic device and scanned with computed tomography prior to, and following, instrumentation at 3, 6 and 9 mm from the root apex. The canal degree of transportation and centering ability were calculated and analyzed using one-way ANOVA and Tukey’s tests (α = 0.05. The results demonstrated no significant difference (p > 0.05 in shaping ability among the rotary systems. The mean canal transportation was: -0.049 ± 0.083 mm (HR; -0.004 ± 0.044 mm (LB; -0.003 ± 0.064 mm (PT; -0.021 ± 0.064 mm (TF. The mean canal centering ability was: -0.093 ± 0.147 mm (HR; -0.001 ± 0.100 mm (LB; -0.002 ± 0.134 mm (PT; -0.033 ± 0.133 mm (TF. Also, there was no significant difference among the root segments (p > 0.05. It was concluded that the Hero 642, Liberator, ProTaper, and Twisted File rotary systems could be safely used in curved canal instrumentation, resulting in satisfactory preservation of the original canal shape.

  4. Effect of three different rotary instrumentation systems on postinstrumentation pain: A randomized clinical trial

    Science.gov (United States)

    Subbiya, Arunajatesan; Cherkas, Pavel S.; Vivekanandhan, Paramasivam; Geethapriya, Nagarajan; Malarvizhi, Dhakshinamoorthy; Mitthra, Suresh

    2017-01-01

    Background: Endodontic instrumentation is liable to cause some postinstrumentation pain (PIP). Rotary endodontic instruments differ in their design, metallurgy, surface treatment, etc. Aim: This randomized clinical trial aimed to assess the incidence of PIP after root canal instrumentation with three different rotary endodontic systems which differ in their design, namely, ProTaper, Mtwo, and K3. Materials and Methods: A total of 150 patients between the ages of 25 and 50 were chosen for the study. Teeth with asymptomatic irreversible pulpitis due to carious exposure were selected. The patients received local anesthesia by inferior alveolar nerve block. After preparing the access cavity, root canal instrumentation was done with one of the three instruments (n = 50) and closed dressing was given. PIP was assessed every 12 h for 5 days, and tenderness to percussion was analyzed at the end of 1, 3, and 7 days. Statistical Analysis: Mann–Whitney U-test to determine significant differences at P Rotary endodontic instrumentation causes some degree of PIP and tenderness to percussion. Among the instruments used, Mtwo causes less PIP and tenderness when compared to ProTaper and K3, and there was no difference between ProTaper and K3. Clinical Relevance: PIP is highly subjective and may vary among different subjects. The apical (3 mm) taper of ProTaper was 0.08 followed by a smaller taper, whereas, the other two files were of a constant 0.06 taper, which means there could have been a greater apical extrusion and therefore more PIP. Despite, the mean of the age was similar, there could have been a difference in the size of the canal and therefore a difference in apical extrusion and PIP. PMID:29430103

  5. Endodontic retreatment: clinical comparison of reciprocating systems versus rotary system in disinfecting root canals.

    Science.gov (United States)

    Martinho, Frederico C; Freitas, Lilian F; Nascimento, Gustavo G; Fernandes, Aleteia M; Leite, Fabio R M; Gomes, Ana P M; Camões, Izabel C G

    2015-07-01

    This clinical study was conducted to compare the effectiveness of single-file reciprocating systems and rotary systems in removing endotoxins and cultivable bacteria in endodontic retreatment. Thirty endodontically treated teeth with post-treatment apical periodontitis were selected. The specimens were divided into three groups according to the system used: WaveOne (n = 10), Reciproc instrument (n = 10), and ProTaper Universal Retreatment system (n = 10). Samples were collected before and after chemomechanical preparation. The irrigation was performed by using 2.5% sodium hypochlorite. A chromogenic limulus amebocyte lysate assay test was used to quantify endotoxins. Culture techniques were used to determine bacterial colony-forming unit counts. At baseline, endotoxins and cultivable bacteria were recovered from 100% of the root canal samples in a median value of 5.84 EU/mL and 4.98 × 10(3) CFU/mL, respectively. After CMP, no differences were found in the median percentage values of endotoxin reduction achieved with reciprocating systems-WaveOne [94.11%] and Reciproc [93.29%] and with rotary systems-ProTaper [94.98%] (P > 0.05). Both single-file reciprocating systems [WaveOne (98.27%) and Reciproc (99.54%)] and rotary system [ProTaper (98.73%)] were effective in reducing bacterial load (P > 0.05). Moreover, no differences were found among the systems tested. The Reciproc and WaveOne reciprocating systems were as effective as the ProTaper system for removal of endotoxins and bacteria in endodontic retreatment. All systems tested were effective to remove cultivable bacteria and endotoxin in endodontic retreatment. As no differences among systems were observed, it is possible to suggest that clinicians should choose the preferred technique to perform endodontic.

  6. Computed tomography evaluation of rotary systems on the root canal transportation and centering ability

    International Nuclear Information System (INIS)

    Pagliosa, Andre; Raucci-Neto, Walter; Silva-Souza, Yara Teresinha Correa; Alfredo, Edson; Sousa-Neto, Manoel Damiao; Versiani, Marco Aurelio

    2015-01-01

    The endodontic preparation of curved and narrow root canals is challenging, with a tendency for the prepared canal to deviate away from its natural axis. The aim of this study was to evaluate, by cone-beam computed tomography, the transportation and centering ability of curved mesiobuccal canals in maxillary molars after biomechanical preparation with different nickel-titanium (NiTi) rotary systems. Forty teeth with angles of curvature ranging from 20° to 40° and radii between 5.0 mm and 10.0 mm were selected and assigned into four groups (n = 10), according to the biomechanical preparative system used: Hero 642 (HR), Liberator (LB), ProTaper (PT), and Twisted File (TF). The specimens were inserted into an acrylic device and scanned with computed tomography prior to, and following, instrumentation at 3, 6 and 9 mm from the root apex. The canal degree of transportation and centering ability were calculated and analyzed using one-way ANOVA and Tukey’s tests (α = 0.05). The results demonstrated no significant difference (p > 0.05) in shaping ability among the rotary systems. The mean canal transportation was: -0.049 ± 0.083 mm (HR); -0.004 ± 0.044 mm (LB); -0.003 ± 0.064 mm (PT); -0.021 ± 0.064 mm (TF). The mean canal centering ability was: -0.093 ± 0.147 mm (HR); -0.001 ± 0.100 mm (LB); -0.002 ± 0.134 mm (PT); -0.033 ± 0.133 mm (TF). Also, there was no significant difference among the root segments (p > 0.05). It was concluded that the Hero 642, Liberator, ProTaper, and Twisted File rotary systems could be safely used in curved canal instrumentation, resulting in satisfactory preservation of the original canal shape. (author)

  7. Computed tomography evaluation of rotary systems on the root canal transportation and centering ability

    Energy Technology Data Exchange (ETDEWEB)

    Pagliosa, Andre; Raucci-Neto, Walter; Silva-Souza, Yara Teresinha Correa; Alfredo, Edson, E-mail: ysousa@unaerp.br [Universidade de Ribeirao Preto (UNAERP), SP (Brazil). Fac. de Odontologia; Sousa-Neto, Manoel Damiao; Versiani, Marco Aurelio [Universidade de Sao Paulo (USP), Ribeirao Preto, SP (Brazil). Fac. de Odoentologia

    2015-03-01

    The endodontic preparation of curved and narrow root canals is challenging, with a tendency for the prepared canal to deviate away from its natural axis. The aim of this study was to evaluate, by cone-beam computed tomography, the transportation and centering ability of curved mesiobuccal canals in maxillary molars after biomechanical preparation with different nickel-titanium (NiTi) rotary systems. Forty teeth with angles of curvature ranging from 20° to 40° and radii between 5.0 mm and 10.0 mm were selected and assigned into four groups (n = 10), according to the biomechanical preparative system used: Hero 642 (HR), Liberator (LB), ProTaper (PT), and Twisted File (TF). The specimens were inserted into an acrylic device and scanned with computed tomography prior to, and following, instrumentation at 3, 6 and 9 mm from the root apex. The canal degree of transportation and centering ability were calculated and analyzed using one-way ANOVA and Tukey’s tests (α = 0.05). The results demonstrated no significant difference (p > 0.05) in shaping ability among the rotary systems. The mean canal transportation was: -0.049 ± 0.083 mm (HR); -0.004 ± 0.044 mm (LB); -0.003 ± 0.064 mm (PT); -0.021 ± 0.064 mm (TF). The mean canal centering ability was: -0.093 ± 0.147 mm (HR); -0.001 ± 0.100 mm (LB); -0.002 ± 0.134 mm (PT); -0.033 ± 0.133 mm (TF). Also, there was no significant difference among the root segments (p > 0.05). It was concluded that the Hero 642, Liberator, ProTaper, and Twisted File rotary systems could be safely used in curved canal instrumentation, resulting in satisfactory preservation of the original canal shape. (author)

  8. MEMS Rotary Engine Power System

    Science.gov (United States)

    Fernandez-Pello, A. Carlos; Pisano, Albert P.; Fu, Kelvin; Walther, David C.; Knobloch, Aaron; Martinez, Fabian; Senesky, Matt; Stoldt, Conrad; Maboudian, Roya; Sanders, Seth; Liepmann, Dorian

    This work presents a project overview and recent research results for the MEMS Rotary Engine Power System project at the Berkeley Sensor & Actuator Center of the University of California at Berkeley. The research motivation for the project is the high specific energy density of hydrocarbon fuels. When compared with the energy density of batteries, hydrocarbon fuels may have as much as 20x more energy. However, the technical challenge is the conversion of hydrocarbon fuel to electricity in an efficient and clean micro engine. A 12.9 mm diameter Wankel engine will be shown that has already generated 4 Watts of power at 9300rpm. In addition, the 1mm and 2.4 mm Wankel engines that BSAC is developing for power generation at the microscale will be discussed. The project goal is to develop electrical power output of 90milliwatts from the 2.4 mm engine. Prototype engine components have already been fabricated and these will be described. The integrated generator design concept utilizes a nickel-iron alloy electroplated in the engine rotor poles, so that the engine rotor also serves as the generator rotor.

  9. Comparative Evaluation of Smear Layer and Debris on the Canal Walls prepared with a Combination of Hand and Rotary ProTaper Technique using Scanning Electron Microscope.

    Science.gov (United States)

    Kiran, S; Prakash, Sandeep; Siddharth, Pujari R; Saha, Supradip; Geojan, Naiza E; Ramachandran, Mookambika

    2016-07-01

    The effect of smear layer and debris on the success rate of endodontic treatment has not yet been definitely determined. So the present study was aimed to evaluate the amount of smear layer and debris on the canal walls prepared with a combination of hand and rotary ProTaper technique using NaOCl and ethylenediaminetetraacetic acid (EDTA) alternately as root canal irrigants using scanning electron microscope (SEM). Eighty intact freshly extracted human permanent mandibular premolar teeth were collected and randomly divided equally into four groups. In group I canals were prepared with hand K-Flexofiles; group II with rotary ProTaper instruments; group III with rotary ProTaper instruments and final instrumentation was done with hand K-Flexofile; group IV with rotary ProTaper instruments and final instrumentation was done with RC-Prep and irrigated with 1 mL of normal saline. In all groups canals were irrigated using NaOCl and EDTA alternately. After instrumentation, the teeth were prepared for SEM examination using five-score indices for debris and smear layer at coronal, middle, and apical third levels. Statistical analysis was performed using chi-square test (p hand files after automated rotary preparation could result in cleaner canal walls. Alternate irrigation with NaOCl and EDTA is effective in the removal of debris and smear layer in the coronal and middle level, but the effectiveness in the apical third is less.

  10. Fatigue resistance of engine-driven rotary nickel-titanium instruments produced by new manufacturing methods.

    Science.gov (United States)

    Gambarini, Gianluca; Grande, Nicola Maria; Plotino, Gianluca; Somma, Francesco; Garala, Manish; De Luca, Massimo; Testarelli, Luca

    2008-08-01

    The aim of the present study was to investigate whether cyclic fatigue resistance is increased for nickel-titanium instruments manufactured by using new processes. This was evaluated by comparing instruments produced by using the twisted method (TF; SybronEndo, Orange, CA) and those using the M-wire alloy (GTX; Dentsply Tulsa-Dental Specialties, Tulsa, OK) with instruments produced by a traditional NiTi grinding process (K3, SybronEndo). Tests were performed with a specific cyclic fatigue device that evaluated cycles to failure of rotary instruments inside curved artificial canals. Results indicated that size 06-25 TF instruments showed a significant increase (p 0.05) in the mean number of cycles to failure when compared with size 06-20 GT series X instruments. The new manufacturing process produced nickel-titanium rotary files (TF) significantly more resistant to fatigue than instruments produced with the traditional NiTi grinding process. Instruments produced with M-wire (GTX) were not found to be more resistant to fatigue than instruments produced with the traditional NiTi grinding process.

  11. MATHEMATICAL MODEL FOR THE STUDY AND DESIGN OF A ROTARY-VANE GAS REFRIGERATION MACHINE

    Directory of Open Access Journals (Sweden)

    V. V. Trandafilov

    2016-08-01

    Full Text Available This paper presents a mathematical model of calculating the main parameters the operating cycle, rotary-vane gas refrigerating machine that affect installation, machine control and working processes occurring in it at the specified criteria. A procedure and a graphical method for the rotary-vane gas refrigerating machine (RVGRM are proposed. A parametric study of the main geometric variables and temperature variables on the thermal behavior of the system is analyzed. The model considers polytrope index for the compression and expansion in the chamber. Graphs of the pressure and temperature in the chamber of the angle of rotation of the output shaft are received. The possibility of inclusion in the cycle regenerative heat exchanger is appreciated. The change of the coefficient of performance machine after turning the cycle regenerative heat exchanger is analyzed. It is shown that the installation of a regenerator RVGRM cycle results in increased COP more than 30%. The simulation results show that the proposed model can be used to design and optimize gas refrigerator Stirling.

  12. Influence of the relative rotational speed on component features in micro rotary swaging

    Directory of Open Access Journals (Sweden)

    Ishkina Svetlana

    2015-01-01

    Full Text Available Micro rotary swaging is a cold forming process for production of micro components with determined geometry and surface. It is also possible to change the microstructure of wires and hence the material properties. Swaging dies revolve around the work piece with an overlaid radial oscillation. Newly developed tools (Flat Surface Dies, FSD feature plain surfaces and do not represent the geometry of the formed part as in conventional swaging. Using these tools allows for producing wires with triangle geometry (cross section as well as a circular shape. To test the influence of FSD on material properties by micro swaging a new method is investigated: the variation of the relative speed between the specimen and dies in infeed rotary swaging. During this specific process copper (C11000 and steel (304 Alloy wires with diameter d0 = 1 mm are formed. It is noticed that the mechanical characteristics such as ductility and strength differ from the characteristics after conventional swaging. Moreover this approach enables new possibilities to influence the geometry and the surface quality of wires. The impact of the relative speed on the processed wire features is described in this paper.

  13. Spatial Domain Adaptive Control of Nonlinear Rotary Systems Subject to Spatially Periodic Disturbances

    Directory of Open Access Journals (Sweden)

    Yen-Hsiu Yang

    2012-01-01

    Full Text Available We propose a generic spatial domain control scheme for a class of nonlinear rotary systems of variable speeds and subject to spatially periodic disturbances. The nonlinear model of the rotary system in time domain is transformed into one in spatial domain employing a coordinate transformation with respect to angular displacement. Under the circumstances that measurement of the system states is not available, a nonlinear state observer is established for providing the estimated states. A two-degree-of-freedom spatial domain control configuration is then proposed to stabilize the system and improve the tracking performance. The first control module applies adaptive backstepping with projected parametric update and concentrates on robust stabilization of the closed-loop system. The second control module introduces an internal model of the periodic disturbances cascaded with a loop-shaping filter, which not only further reduces the tracking error but also improves parametric adaptation. The overall spatial domain output feedback adaptive control system is robust to model uncertainties and state estimated error and capable of rejecting spatially periodic disturbances under varying system speeds. Stability proof of the overall system is given. A design example with simulation demonstrates the applicability of the proposed design.

  14. Fracture resistance of dental nickel–titanium rotary instruments with novel surface treatment: Thin film metallic glass coating

    Directory of Open Access Journals (Sweden)

    Chih-Wen Chi

    2017-05-01

    Conclusion: The novel surface treatment of Ti-Zr-B thin film metallic glass on dental NiTi rotary files can effectively improve the fatigue fracture resistance by offering a smooth coated surface with amorphous microstructure.

  15. Comparison among manual instruments and PathFile and Mtwo rotary instruments to create a glide path in the root canal preparation of curved canals.

    Science.gov (United States)

    Alves, Vanessa de Oliveira; Bueno, Carlos Eduardo da Silveira; Cunha, Rodrigo Sanches; Pinheiro, Sérgio Luiz; Fontana, Carlos Eduardo; de Martin, Alexandre Sigrist

    2012-01-01

    Nickel-titanium rotary instruments reduce procedural errors and the time required to finish root canal preparation. The goal of this study was to evaluate the occurrences of apical transportation and canal aberrations produced with different instruments used to create a glide path in the preparation of curved root canals, namely manual K-files (Dentsply Maillefer, Ballaigues, Switzerland) and PathFile (Dentsply Maillefer) and Mtwo (Sweden and Martina, Padua, Italy) nickel-titanium rotary files. The mesial canals of 45 mandibular first and second molars (with curvature angles between 25° and 35°) were selected for this study. The specimens were divided randomly into 3 groups with 15 canals each, and canal preparation was performed by an endodontist using #10-15-20 K-type stainless steel manual files (group M), #13-16-19 PathFile rotary instruments (group PF), and #10-15-20 Mtwo rotary instruments (group MT). The double digital radiograph technique was used, pre- and postinstrumentation, to assess whether apical transportation and/or aberration in root canal morphology occurred. The initial and final images of the central axis of the canals were compared by superimposition through computerized analysis and with the aid of magnification. The specimens were analyzed by 3 evaluators, whose calibration was checked using the Kendall agreement test. No apical transportation or aberration in root canal morphology occurred in any of the teeth; therefore, no statistical analysis was conducted. Neither the manual instruments nor the PathFile or Mtwo rotary instruments used to create a glide path had any influence on the occurrence of apical transportation or produced any canal aberration. Copyright © 2012 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  16. Comparison of air-driven vs electric torque control motors on canal centering ability by ProTaper NiTi rotary instruments.

    Science.gov (United States)

    Zarei, Mina; Javidi, Maryam; Erfanian, Mahdi; Lomee, Mahdi; Afkhami, Farzaneh

    2013-01-01

    Cleaning and shaping is one of the most important phases in root canal therapy. Various rotary NiTi systems minimize accidents and facilitate the shaping process. Todays NiTi files are used with air-driven and electric handpieces. This study compared the canal centering after instrumentation using the ProTaper system using Endo IT, electric torque-control motor, and NSK air-driven handpiece. This ex vivo randomized controlled trial study involved 26 mesial mandibular root canals with 10 to 35° curvature. The roots were randomly divided into 2 groups of 13 canals each. The roots were mounted in an endodontic cube with acrylic resin, sectioned horizontally at 2, 6 and 10 mm from the apex and then reassembled. The canals were instrumented according to the manufacturer's instructions using ProTaper rotary files and electric torque-control motors (group 1) or air-driven handpieces (group 2). Photographs of the cross-sections included shots before and after instrumentation, and image analysis was performed using Photoshop software. The centering ability and canal transportation was also evaluated. Repeated measurement and independent t-test provided statistical analysis of canal transportation. The comparison of the rate of transportation toward internal or external walls between the two groups was not statistically significant (p = 0.62). Comparison of the rate of transportation of sections within one group was not significant (p = 0.28). Use of rotary NiTi file with either electric torquecontrol motor or air-driven handpiece had no effect on canal centering. NiTi rotary instruments can be used with air-driven motors without any considerable changes in root canal anatomy, however it needs the clinician to be expert.

  17. Ex Vivo Comparison of Mtwo and RaCe Rotary File Systems in Root Canal Deviation: One File Only versus the Conventional Method.

    Science.gov (United States)

    Aminsobhani, Mohsen; Razmi, Hasan; Nozari, Solmaz

    2015-07-01

    Cleaning and shaping of the root canal system is an important step in endodontic therapy. New instruments incorporate new preparation techniques that can improve the efficacy of cleaning and shaping. The aim of this study was to compare the efficacy of Mtwo and RaCe rotary file systems in straightening the canal curvature using only one file or the conventional method. Sixty mesial roots of extracted human mandibular molars were prepared by RaCe and Mtwo nickel-titanium (NiTi) rotary files using the conventional and only one rotary file methods. The working length was 18 mm and the curvatures of the root canals were between 15-45°. By superimposing x-ray images before and after the instrumentation, deviation of the canals was assessed using Adobe Photoshop CS3 software. Preparation time was recorded. Data were analyzed using three-way ANOVA and Tukey's post hoc test. There were no significant differences between RaCe and Mtwo or between the two root canal preparation methods in root canal deviation in buccolingual and mesiodistal radiographs (P>0.05). Changes of root canal curvature in >35° subgroups were significantly more than in other subgroups with smaller canal curvatures. Preparation time was shorter in one file only technique. According to the results, the two rotary systems and the two root canal preparation methods had equal efficacy in straightening the canals; but the preparation time was shorter in one file only group.

  18. National emission standards for hazardous air pollutants application for approval to construct rotary mode core-sampling truck and exhauster

    International Nuclear Information System (INIS)

    1993-05-01

    Characterization of wastes in the underground single-shell tanks and double-shell tanks on the Hanford Site is crucial in developing the final disposal options for the waste and closure strategy for the Hanford Site. Additionally, characterization of tank waste is important for the waste tank safety programs. The Hanford Federal Facility Agreement and Consent Order (also referred to as the Tri-Party Agreement) Milestone M-10-00 requires the obtaining and analyzing of at least two samples from each single-shell tank, and Milestone M-10-13 specifically requires the ability to sample hard saltcake. Existing equipment does not allow sampling of all single-shell tanks within established tank safety limits. Consequently, the US Department of Energy, Richland Operations Office has developed a rotary mode core-sampling system that uses nitrogen gas to cool and clear the drill bit. A rotary mode core-sampling truck will be used on approximately 80 single-shell tanks which contain saltcake wastes, and will provide crucial information on the contents of the tanks. This application is a request for approval to construct and operate the rotary mode core-sampling truck and exhauster in the 200 East and 200 West Area Tank Farms of the Hanford Site. This request is being made pursuant to 40 CFR 61, Subpart H

  19. Auto-Gopher: A Wire-Line Rotary-Hammer Ultrasonic Drill

    Science.gov (United States)

    Badescu, Mircea; Sherrit, Stewart; Bao, Xiaogi; Bar-Cohen, Yoseph; Chen, Beck

    2011-01-01

    Developing technologies that would enable NASA to sample rock, soil, and ice by coring, drilling or abrading at a significant depth is of great importance for a large number of in-situ exploration missions as well as for earth applications. Proven techniques to sample Mars subsurface will be critical for future NASA astrobiology missions that will search for records of past and present life on the planet, as well as, the search for water and other resources. A deep corer, called Auto-Gopher, is currently being developed as a joint effort of the JPL's NDEAA laboratory and Honeybee Robotics Corp. The Auto-Gopher is a wire-line rotary-hammer drill that combines rock breaking by hammering using an ultrasonic actuator and cuttings removal by rotating a fluted bit. The hammering mechanism is based on the Ultrasonic/Sonic Drill/Corer (USDC) that has been developed as an adaptable tool for many of drilling and coring applications. The USDC uses an intermediate free-flying mass to transform the high frequency vibrations of the horn tip into a sonic hammering of a drill bit. The USDC concept was used in a previous task to develop an Ultrasonic/Sonic Ice Gopher. The lessons learned from testing the ice gopher were implemented into the design of the Auto-Gopher by inducing a rotary motion onto the fluted coring bit. A wire-line version of such a system would allow penetration of significant depth without a large increase in mass. A laboratory version of the corer was developed in the NDEAA lab to determine the design and drive parameters of the integrated system. The design configuration lab version of the design and fabrication and preliminary testing results are presented in this paper

  20. Influence of Heat Treatment of Nickel-Titanium Rotary Endodontic Instruments on Apical Preparation: A Micro-Computed Tomographic Study.

    Science.gov (United States)

    de Almeida, Bernardo Corrêa; Ormiga, Fabíola; de Araújo, Marcos César Pimenta; Lopes, Ricardo Tadeu; Lima, Inayá Corrêa Barbosa; dos Santos, Bernardo Camargo; Gusman, Heloisa

    2015-12-01

    The aim of this study was to make a 3-dimensional comparison of the canal transportation and changes in apical geometry using micro-computed tomographic imaging after canal preparation with K3 (SybronEndo, Orange, CA) and K3XF (SybronEndo) file systems. Twenty-eight mandibular molars were randomly divided into 2 groups according to the rotary system used in instrumentation: K3 or K3XF. The specimens were scanned by micro-computed tomographic imaging before and after instrumentation. Images before and after instrumentation from each group were compared with regard to canal volume, surface area, and structure model index (SMI) (paired t test, P instrumentation, the canals from each group were compared regarding the changes in volume, surface area, SMI, and canal transportation in the last 4 apical mm (t test, P Instrumentation with the 2 rotary systems significantly changed the canal volume, surface area, and SMI (P instrument types concerning these parameters (P > .05). There were no significant differences between the 2 groups with regard to canal transportation in the last 4 apical mm (P > .05). Both rotary systems showed adequate canal preparations with reduced values of canal transportation. Heat treatment did not influence changes in root canal geometry in the apical region. Copyright © 2015 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.